Tourism in Turkey and its effects in the Grand Tarabya Hotel Term Paper

Tourism in Turkey and its effects in the Grand Tarabya Hotel - Term Paper Example This aspect stimulates the probable growth of the Grand Tarabya hotel across the country, while branching and enjoying economies of scale profitably. The research implements the overall impacts that the country, Turkey, and the Grand Tarabya Hotel enjoy from different practices towards international tourism sector. Tourism in turkey The country possesses a vast and beautiful Mediterranean coast that owns magnificent seaside beaches, with some of them having chronological factors (Bramwell, 2004). The country’s city of Istanbul bears a rich heritage of a distinct culture emanating from the music, dressing, to global business. The country owns a wide range of tourist attractions thus drawing many, for example, the country’s growing economy attracts international investors (Hall, 2006). There is a propellant reason that the country’s political stature maintains business-oriented views towards all the economic sectors, whilst maintaining a profound degree of stabilit y and heritage to draw positive attention towards the country’s activities. Turkey’s Istanbul city is the home of the historical Ottoman Empire that ruled for 653years, from the 13th to the 20th centuries. The empire stretched through the European, Asian, and African continents alike with a monarchical and stringent leadership. Another historical feature in turkey is the Blue Mosque that dates from the 1609-1616, yet the architectural features stand out for their exotic beauty. The Dead Sea in Turkey, with elongated lagoons from the land serves for beaches and resorts from all dimensions. The country owns a vast number of resorts with more than a thousand in the city of Istanbul. The country boasts of the wide attraction, drawing almost all races from different continents across the world (Bramwell, 2004). The Grand Tarabya Hotel The hotel situated at the historical Tarabya town inherits a great perspective of the towns’ history, formerly referred by the Greek a s Therapia with the notion that the offshore town had healing features. The notion created an avenue for the rich, wealthy, and the rulers to crave and establish their presence in the town accordingly. According to history, the grand Tarabya hotel was the home of ancient rulers of the Ottoman Empire. Therefore, the hotel inherits a foundation of rich culture and this aspect serves to draw visitors closer. The hotel, currently under renovation, draws attraction from local to the global tourism markets (Hall, 2006). The hotel further establishes a spectacle view to the sea, and the entire town, which serve for an attraction. Literature review The research project depicts relevance to the overall tourism effects to the country of turkey and the Grand Tarabya Hotel. In the research, tourism poses as an economic activity to Turkey and the importance relates directly to the hotel industry (Urry, 2011). The research implements findings on the following objectives: The push and pull factors to the international tourist, mainly these are the factors that draw tourists into the country. The research seeks to establish on the strategies that the country reinforces to the world thus drawing people’s attention towards the country. Mainly, the country may advertise on different contributing variables ranging from, economic to social factors that

Leave No Child Behind, Reading First Essay Example | Topics and Well Written Essays - 1500 words

Leave No Child Behind, Reading First - Essay Example It aims to formulate methods and tools from research to complement the course and monitor effectiveness of the program through grade level testing. President Bush commitment that all American children will receive a high quality education paved way to the promulgation of the No Child Left Behind Act (NCLB) of 2001 enacting Bipartisan education reform as the cornerstone of his administration. The NCLB Act was signed by President George Bush on January 8, 2002. (US Dept. of Educ., Overview, 2005) Literally mapping a state of difference with regards to budget implementation and measure of education control and monitoring success gives America an edge to measure education progress by creatively emphasizing school competitiveness and reports on performance system. The No Child Left Behind Act increases the accountability of the schools, school districts and the States to the Capital. It aims to give parents a better option to allow them to choose which public school their children will attend. It increased its focus to reading and act on the perspective of standard based education reform. It was a bipartisan reform act of Senator Edward Kennedy and President George Bush. ... In the 107th congress in March 2001, the Act began as House Resolution 1. It passed the House of Representatives on December 13, 2001 and the Senate on December 18, 2001. (Wikipedia Foundation, 2006) C. Provisions and Features of NCLB Act To complement the all American aim of competing global market technology and labor, President Bush prepared the nation a firm base to start future production of American geniuses. This entirely theorize the computation of the life span of a person to determine age towards starting state responsibility through reading comprehension as early as the age level of the third grade. Increasing the literacy of the people especially the children makes the Capital manage a very intelligent and highly interactive state voter that can navigate economics and politics globally. This is a wise vision of a nation transformation to 100% literacy and a fore runner in world class standard education programs. Applauding the NCLB Act, it could mean a fore runner in almost everything, science, industry, politics, technology and economics. 1. Funding The government has been spending a lot on this education reform act to all of the states to improve education and the upgrade schools standards and efficiency. In relation thereof, every parent has the right to choose which public school they want to send their child in case the school by which their child is presently studying does not qualify or satisfy their choices. As an extension, in case the proximity of the school is a little farther from the current school location the parents reserve the right to ask for transportation allowance from the school districts from which they belong for this matter. Everything is being taken cared of. There absolutely is no reason for the school or the

Utilisation of Wind Energy for High Rise Building Power

Utilisation of Wind Energy for High Rise Building Power Introduction The price of conventional energy is on the rise, due to the ever-widening gap between demands and supply. The main reason for such shortages is the depletion in natural resources, such as coal, which is the main fuel used for electrical energy generation. Since these fuels are made up of carbon compounds, burning them has rapidly increased the amount of carbon dioxide in the atmosphere over the last 100 years. This has brought about a chain reaction of hazards such as global warming, climate change, destruction of ecosystems, etc with predictions for adverse outcomes in the future. In response to this threat and to initiate an end to such processes, the UN agreed the Kyoto Protocol in Japan in 1997. This requires industrialised nations to reduce greenhouse gas emissions by 5% of 1990 levels by 2008-2012. The UK has agreed to meet this target and furthered its promise by setting a goal of 50% reduction in carbon emissions by 2050[ ]. Part of its government energy policy is to increase the contribution of electricity supplied by renewable energy to 10% by 2010 (Blackmore P, 2004). A similar promise has been undertaken by many world nations, which has led to a plethora of new and innovative methods for power generation. Renewable is the key to climate friendly forms of energy, due to the absence of emissions detrimental to the environment (Stiebler M, 2008). It includes energy derived from sunlight, wind, wave, tides and geothermal heat. Out of the afore mentioned resources, geothermal heat is restricted to only limited locations on the globe while wave and tidal power is still in its research stage. Thus sunlight and wind are the key elements that can be tapped for energy generation. However, on comparison between the two systems, wind energy systems are more advantageous both in availability of resources and cost of generation. This report mainly focuses on wind energy, with a keen interest on harvesting it for ventilation and power generation purposes in high-rise buildings. Plan forms that aid this purpose will be studied using Computational Fluid Dynamics to understand the flow of wind in and around a thirty-storey structure and the building configuration well suited for natural ventilation and wind turbine integration would be identified at the end of the test. To obtain a complete picture of wind flow patterns and to closely mimic real life situations, the wind will be simulated from different directions at different wind speeds. Wind energy Wind is the term used for air in motion and is usually applied to the natural horizontal motion of the atmosphere (Taranath Bungale S, 2005). It is brought about by the movement of atmospheric air masses that occur due to variations in atmospheric pressure, which in turn are the results of differences in the solar heating of different parts of the earth’s surface (Boyle G, 2004). At a macro level wind profile differs from place to place depending on geographic location and climatic conditions while in a microstate the immediate physical environment of a particular place modifies the nature of the winds. For example, the velocity of the wind recorded in the countryside which has acres of unobstructed grassland would be greater than that recorded in a city dominated by skyscrapers. Hence to obtain a clear idea of the wind characteristic corresponding to a particular area the wind rose is utilized. They are based on metrological observations and depict the varying wind speeds experienced by a site at different times of the year together with the frequency of different wind directions [ ]. It is the first tool consulted to judge the wind resources of a site and its ability to support power generation. The winds have been tapped from ancient times by means of ship sails, windmills, wind catchers, etc. The history of windmills goes back more than 2000 years (Stiebler M, 2008) when they were predominantly used for grinding grain and pumping water. However, the breakthrough occurred when Charles.F.Brush erected the first automatically operating wind turbine at Ohio in 1888 [ ]. It was fabricated using wood and had a rotor diameter of 17m with 144 blades. The system recorded very low efficiency and was mainly used to charge batteries. The reason behind the poor efficiency was due to the large number of blades, which was later discovered by Poul la Cour who introduced fewer blades into his wind turbine. Though such developments were achieved at an early stage in innovation, it was not until 1980 that the prominent application of renewable energies was sought after (Boyle G, 2004). Wind energy is the harnessing of the kinetic energy prevalent in moving air masses. This kinetic energy for any particular mass of moving air (Boyle G, 2004) is given by the formula: K.E = 0.5mV ² where, m – mass of the air (kg) and V – wind velocity (m/s). However this mass of moving air per second is: m = air density x volume of air flowing per second m = air density x area x velocity   Thus, m = rAV where, r – density of air at sea level = 1.2256 kg/m ³ and A – area covered by the flowing air (m ²) Substituting this value of m in the former equation, K.E. = 0.5rAV ³ (J/s) But energy per unit of time is power and hence the above equation is the power available from the wind. It is also evident that the power is directly proportional to thrice the wind velocity. In other words even a marginal increase in wind speed would yield three folds of the nominal power. This is the critical fact based on which the whole energy process is evolved. However not all of this power can be exhausted since it would lead to nil outflow through the wind turbine, that is no flow of air behind the rotor. This would lead to no flow of air over the turbine causing total failure of the system. According to Albert Betz the maximum amount of power that can be harnessed from the wind is 59.3%. This is often referred to as the Betz limit and has been proven by modern experiments. Some of the advantages of wind energy include: It is based on a non-exhaustive resource and hence can be harnessed for generations. It is a clean and eco friendly way of producing energy. In its working lifetime, the wind turbine produces eighty times the amount of energy that goes into its manufacturing and thus has diminishable net impact on the environment. It does not require any additional resources such as water supply unlike conventional power generation. It can boost the economy of the region (wind farms). Wind turbines: Wind turbines are the modern day adaptations of the yesteryear windmills but unlike their counterparts they are mainly used for power generation. These new age systems come in different shapes and have various configurations, the well established of them all are the Horizontal axis wind turbine and the Vertical axis wind turbine. Write a brief about horizontal wind turbines and vertical wind turbines. BUilding integrated Wind Turbines (BUWT): Building integrated wind turbines are associated with buildings designed and shaped with wind energy in mind (Stankovic S et al, 2009). They are relatively a new way of harnessing energy that is gaining popularity at a quick pace. Small scale wind turbines on house roofs and retrofitting also fall under this category. The design of BUWTs is a complicated affair and involves the careful consideration of various factors. Since turbines are fixed into the building’s fabric its impact on the environment, building’s response and needs of its owners and occupants need to be weighed equally. Also numerous design decisions such as planning, structure, services, construction and maintenance depend on this single process (Stankovic S et al, 2009). With the increase in the scale of the proposal the importance of these factors increases simultaneously. The proposal generally spans from the number, scale, type and location of the turbines together with its annual energy yield and design life. A good BUWT based building should be a wholesome design that does not prejudice the buildings efficient functioning for energy generation. Generic options for BUWTs: Stankovic S et al (2009) explains that the wind turbines can be fixed on to a building in enumerable ways. Each method can accomplish a different level of power depending on the type of turbine used and the form of the building it is mounted upon. On top of a square/ rectangular building: This configuration is on the principle that the wind velocity increases with height and hence the amount of energy generated would be of a higher order (10% increase with wind acceleration). An added advantage is that the turbine would experience relatively little turbulence. But access to the turbine for maintenance and decommissioning works may be difficult. If mounted on tall buildings the turbines may threaten the visual quality of the skyline. On top of a rounded building: This case is very similar to the previous configuration except that with the use of rounded faà §ade the mean tower height can be considerably diminished. Also the rounded profile influences the local acceleration (15% increase in energy). The low tower height favors easy access to the turbine but leads to blade flicker and noise issues. Concentrator on top of a rounded building: This case is well suited to areas with bi-directional winds (20% energy increase over a free standing equivalent due to local acceleration). Vertical axis wind turbines are better suited for this feature while Horizontal axis wind turbines need to be suitably altered to achieve the same status. The building spaces that act as concentrators may be inhabited with suitable acoustical treatment. This case also encounters the same drawbacks as listed in the previous case. Square concentrator within a building faà §ade: As before, this configuration takes advantage of the higher quality winds at higher altitudes and local acceleration thereby achieving 25% increase in energy and 40% increase for bi-directional winds. This option is best suited for buildings with narrower profiles. There may be a loss in the saleable area of the building but the aperture can be converted into an exclusive feature such as a sky garden. The opening also relieves the wind loading on the building’s facade leading to simpler structural solutions. Vertical axis wind turbine is the only choice for integration due to its square swept area. Circular concentrator within a building faà §ade: This is very similar to the square concentrator except the opening is accustomed to hold pitch controlled horizontal axis wind turbines with fixed yaw. Also, a 35% increase for uniform wind and 50% increase in energy for bi-directional winds are achievable in this method. But on the down side, this technique is more expensive due to the cylindrical shroud. On the side of a building: In this technique, an increase in 80-90% in energy than the freestanding equivalents is achievable only if the building form is optimized to the local wind character. Only reliable vertical axis wind turbines can be used for power generation due to access issues. For higher swept area, more number of turbines should be used. Between multiple building forms: This type of an option opens out many doors for a range of architectural forms. Unlike the previous cases, the buildings orientation, form, shape and spacing play key roles in the performance of the turbines. Vertical axis wind turbines are better suited for this purpose. Guidelines for BUWT’s: The following are some guidelines outlined by Stankovic S et al (2009) for incorporating wind turbines into a structure: BUWTs should be tailored to the specific site for good results. Adequate wind resources should be available on site. If however if the site is under resourced steps are to be adopted to deliberately elevate the quality of the wind through the buildings form or turbine. The impact of its surroundings should also be considered before commissioning such a project. The dominating wind direction and its intensity should be observed from meteorological data. This would help in determining the form and orientation of the building together with finalizing the position of the wind turbine to make the most out of the available resource. Environmental impact assessment corresponding to the site should be carried out to foresee the adverse effects the turbines may create. Acoustic isolation may be sought for in some areas within the building if it lies at close proximity to the rotor. Natural ventilation and day lighting qualities of the building may be challenged and forced to settle for artificial means. The type and position of openings, external shading devices, smoke extracts etc should be handled with appropriate care to avoid draught winds. Access to the wind turbines for maintenance and decommissioning must be provided suitably. The aesthetic quality of the mounted turbines must harmonize with its surroundings and should not over power the pedestrians at ground level. To this end well suited screening devices such as canopies, screens and landscape may be utilized as per the necessity. The overall success of BUWT project depends on its ability to deliver the expected power. Inability to comply with this effect would result in the failure of its intended purpose from both an environmental and design point of view. Thus the electricity demand of the building and the level to which this would be met with should be estimated prior to turbine design to secure maximum benefits. Wind flow prediction and energy yields: For any project to be successful, Wind flow and building design (Taranath Bungale S, 2005) When the air moves in a vertical direction it is referred to as a current. These currents play a major role in meteorology whereas the gradual decrease in wind speed and high turbulence of the horizontal motion of air, at the ground level, are vital in building engineering. In urban areas, this zone of turbulence extends to a height of approximately one quarter of a mile aboveground and is called the surface boundary layer. Above this layer, the horizontal airflow is no longer influenced by the ground effect. The wind speed at this height is known as the gradient wind speed, and it is precisely in this boundary layer where most human activity is conducted. Characteristics of wind: The flow of wind is complex because many flow situations arise from the interaction of wind with structures. A few characteristics of wind include: Variation of wind velocity with height: The viscosity of air reduces its velocity adjacent to the earth’s surface to almost zero. A retarding effect occurs in the wind layers near the ground, and these layers in turn successively slow the outer layers. The slowing down is reduced at each layer as the height increases, and eventually becomes negligibly small. The height at which velocity ceases to increase is called the gradient height, and the corresponding velocity, the gradient velocity. At heights of approximately 366m aboveground, the wind speed is virtually unaffected by surface friction, and its movement is solely dependant on prevailing seasonal and local wind effects the height through which the wind speed is affected by topography is called the atmospheric boundary layer. Wind turbulence: Motion of wind is turbulent and it occurs in wind flow because air has a very low viscosity-about one-sixteenth that of water. Any movement of air at speeds greater than 0.9 to 1.3 m/s is turbulent, causing air particles to move randomly in all directions. Vortex shedding: In general, wind buffering against a bluff body such as a rectangular building gets diverted in three mutually perpendicular directions. However, only the longitudinal winds and the transverse winds or crosswinds are considered in civil engineering. When a free flowing mass of air encounters a building along its path, the originally parallel upwind streamlines are displaced on either side of the building. This results in spiral vortices being shed periodically from the sides into the downstream flow of the wind, called the wake. At relatively low wind speeds the vortices are shed, that is, break away from the surface of the building and an impulse is applied in the transverse direction. Distribution of pressures and suctions: When air flows around the edges of a structure, the resulting pressures at the corners are much in excess of the pressures on the center of elevation. This has been evident by the damages caused to corner windows, eave and ridge tiles, etc in windstorms. Wind tunnel studies conducted on scale models of buildings indicate that three distinct pressure areas develop around the building. They are: Positive pressure zone on the upstream face (Region 1) Negative pressure zone at the upstream corners (Region 2) Negative pressure zone on the downstream face (Region 3) The highest negative pressures are created in the upstream corners designated as Region 2. Wind pressures on a buildings surface are not constant, but fluctuate continuously. The positive pressure on the upstream or the windward face fluctuates more than the negative pressure on the downstream or the leeward face. The negative pressure region remains relatively steady as compared to the positive pressure zone. The fluctuation of pressure is random and varies from point to point on the building surface. Nearby buildings can have a significant influence on wind forces. If they are the same height as the structure being considered then they will mostly provide shelter, although local wind loads can be increased in some situations. Where surrounding buildings are significantly taller they will often generate increased wind loading (negative shelter) on nearby lower structures. Shelter can result from either from the general built-environment upwind of the site or from the direct shielding from specific individual upwind buildings (Blackmore P, 2004). Natural ventilation The three natural ventilation airflow paths in buildings are (Pennycook, 2009): Cross ventilation Single-sided ventilation Passive stack ventilation Advantages of cross ventilation: Greater rates of ventilation can be achieved under amicable weather conditions. Can be utilized for deep-plan spaces with operable windows on the external wall. Incumbents have control over ventilation. Relatively cost free. Can be incorporated with thermal masses. However, it has certain limitations such as: Internal space layout must be hindrance free for easy, clear flow of air. Internal partitions must be within 1.2m height and tall cupboards must be placed alongside the windows. Natural ventilation can occur only under the presence of suitable winds. Poor planning and positioning of windows may cause disruptive draughts and gusts. Winter ventilation is problematic. Unsuitable for buildings located in noisy and pollution prone environments. The requirements of fresh air supply are governed by the type of occupancy, number and activity of the occupants and by the nature of any processes carried out in the space (Koenigsberger et al, 2001). When natural ventilation is stipulated for good indoor air quality, the amount and nature of the dominant pollutant source in the space should be identified. Based on this data the ventilation rate for the space can be calculated such that the pollution level does not cross a preset specific mark. Generally the concentration of the pollutants decreases with the increase in airflow rate (Figure –1). However, in terms of thermal comfort especially during winter the heating requirement of the building will increase with the ventilation rate. This demand varies with time, wind characteristics of the place, opening and closing of windows and doors by its occupants and the thermal state of the building. In summer, cooling is ideal for both the building and its occupants to prevent internal heat gains. By directing the high velocity wind around the human body the evaporative rate at the skins surface can be increased thereby achieving a cooling sensation. The recommended upper limit of indoor air movement is 0.8 m/sec, which permits the inhabitants to occupy a space about 2 °C warmer and 60% relative humidity with optimum comfort. The traditional way to cool buildings is to provide large openings along the exterior wall with the principle that higher the ventilation rate greater the loss of heat to the external environment. But such an arrangement would work only when the outdoor te mperature is in the range of comfort zone. When controlled indoor environments are desired especially during the occupancy period’s night ventilation is recommended. In this technique the building is cooled at night so that it can absorb the heat generated during the day (Allard F, 1998). Based on wind tunnel experimental observations, the factors that affect the indoor airflow are: Orientation: External features: Cross-ventilation: Position of openings: Size of openings: Control of openings: Literature review The following are studies that have been made of different aspects of wind using Computational Fluid dynamics. CFD evaluation of wind speed conditions in passages between parallel buildings: This analysis undertaken by Blocken B et al (2007) mainly focuses on the wind speed conditions in passages between parallel buildings in combination with the accuracy of the commercial CFD code Fluent 6.1.22 when the wall-function roughness modifications are applied to them. The Venturi effect is also studied to determine the amount of increase in wind speed in the passage due to the decrease in flow section. The results obtained were compared with various previously proven experiments carried out by experts in the field. As the title indicated the case undertaken involves a pair of rectangular buildings measuring 40m x 20m x 20m, placed adjacent to each other and separated by a narrow passage. The width of the passage is widened (for example, 2, 4, 6, 8, 10, 15, 20, 30, 40, 60, 80, 100 m) with every case to clearly understand the Venturi effect. The dimension of the computational domain is 20.5x14x18m3; the whole setup is placed at a distance of 5m from the inlet and simulated with a wind speed of 6.8m/sec based on initial results. The results recorded at the end of the simulation process are discussed as follows. They are based on the amplification factor, which is defined as the ratio of the mean wind speed at a certain location to the mean wind speed at the same location without the buildings present. As such it is a direct indication of the effect of the buildings on the wind speed (Blocken B et al, 2007). Pedestrian level wind profile: In context to this research, for narrow passages (example w=2m) this amplification factor occurs maximum at the centerline immediately behind the entrance. When the distance between the buildings are slightly increased (example w=10m), the flow streams deflecting off the inner edges of the buildings combine into a large jet stream and records an increase in the amplification factor. However this property is lost when the width of the passage is of a high order (example w=30m). Overall wind profile: To understand the overall wind profile, six vertical lines were identified along the passage’s center plane for the case of w=6m. The lines depicted the fact that there was an increase in the wind speed at the ground level due to the downdraft of the wind along the front faà §ade of the building and a decrease in wind speed at the end of the passage due to the exit of flow from the passage. Also for these cases, there was no significant increase in the wind speed with the increase in height. Flow rates at different points in the passage: To evaluate the Venturi-effect three fluxes were defined, one along the vertical plane, another along the horizontal plan and the final being similar to the former one but in the absence of the buildings. When the flow rate was calculated for narrow passages, it stated an increase in wind speed by only 8% due to the Venturi effect. However for larger widths the flow rate was lower than the free-field flux. This shows that the wind has a tendency to flow over and around the building rather than be forced through the passage as previously believed. Thus there is a lack of strong Venturi effect and the flow in the passage can be attributed as the channeling effect for these cases. The research also concluded that there were discrepancies in the CFD results due to the use of the roughness factor and advised future users to simulate an empty field before positioning the buildings to clearly identify the difference in results. Further research into the Venturi effect was also implied. Computational analysis of wind driven natural ventilation in buildings: Evola G and Popov V (2006) research focuses on the application of three-dimensional Reynolds Averaged Navier-Strokes (RANS) modeling on wind driven natural ventilation with specific detail to the pressure distribution and flow pattern within the building. The various cases would be simulated with the standard k-e model and the Renormalization Group theory (RNG). Within the framework of natural ventilation both single sided ventilation and cross ventilation would be studied and the results obtained using CFD will be compared with LES models and empirical methods for its reliability.  Ã‚  Ã‚   The building undertaken consists of a 250mm x 250mm x 250mm cube punctured with a centrally located 84mm x 125 mm opening on the wind ward side (Case 1). In Case 2 the door like opening is placed on the leeward side and in Case 3 both the openings are retained to test the cross ventilation principle. On comparison between the CFD results obtained for Case 1 and 2, Case 2 portrays a better flow pattern especially at the mouth of the opening. This leads to a better ventilation rate than Case 1 though in contrast to the theoretical data that good ventilation rate and flow patterns are achievable only when the opening faces the incoming winds. To establish the phenomenon further experimentation into the field was suggested. Between Cases 1, 2 and 3, cross ventilation clearly stands out as the best option of them all, both in terms of velocity and distribution. Also the study concluded that the measured RNG results matched approximately to the theoretical results of Cases 1 and 2. But a significant amount of deviation was observed in Case 3. The RNG model was only slightly intense than the k-e model generally used. The research also concluded that there were discrepancies in the CFD results due to the use of the roughness factor and advised future users to simulate an empty field before positioning the buildings to clearly identify the difference in results. Further research into the Venturi effect was also implied. CFD modeling of unsteady cross-ventilation flows using LES: This research undertaken by Cheng-Hu Hu et al (2008) employs the LES method to investigate the fluctuating ventilation flow rate induced by the wind for a cross-ventilated building. The results from CFD were compared with those previously acquired from wind tunnel tests.   Ã‚   The building proposed for the study consists of a rectangular box with two openings of equal size located opposite to each other. The wind is simulated from 0 °(Case 1) and 90 °(Case 2) to the building at a rate of 1m/sec, to study the flow pattern in and around it. When the air approaches the building the ventilation rate is unsteady at the mouth of the openings due to turbulence and in the flow separation layer due to shear. In Case 1 the wind is accelerated through the opening and directed downwards inside the building. This phenomenon brings about a circulation of the internal air before guiding the wind upwards and out through the window on the leeward side of the building. The air exchange occurs due to the mean flows through the opening. In Case 2 where the wind is parallel to the windows, the air moves in and exits rapidly causing fluctuating flows thereby leading to air exchange. In this case turbulence prone areas are formed at the rear of the building. When these results were compared with the wind tunnel data, Case 1 portrayed similarities while Case 2 had major deviations. Further study was proposed for understanding the reason behind such deviations. Case studies The Bahrain world trade centre was the world’s first building to ‘aesthetically incorporate commercial wind turbines into the fabric of the building’ [ ]. The complex consists of a three-storied sculpted podium and basement from where the 240m high towers rise up into the sky. The two towers comprise of 51 floors each and are connected by means of three, 31.5m span bridges at 60m, 96m and 132m levels [ ]. They are oval in section for aerodynamic reasons and follow a shallow V-shape in plan for adequate blade clearance. Sitting on each of this 70 ton spandrel is an 11-ton nacelle to which the industry approved horizontal axis wind turbines are fixed by special means. The turbine has a rotor diameter of 29m and is stall controlled with centrifugally activated feathering tips for air brakes (Killa S Smith Richard F, 2008). The turbines are oriented facing the Arabian Gulf intercepting the path of the dominant winds. The decision to harness the prevailing wind was thought of from the initial stage drawing inspiration from ‘the regional wind towers and the vast sails of the traditional Arabian Dhow which utilise the wind to drive them forward’. Numerous Computational fluid dynamics models and wind tunnel tests were carried out to determine the final building form. The result was a skyward tapering, elliptical structure, carved out by the wind that functions as aerofoil sections (Wood A, 2008). The shape and spatial relationship of the towers aid in adhering the wind in a â€Å"S’ flow whereby the center of the wind stream remains nearly perpendicular to the turbine within a 45 ° wind azimuth, either side of the central axis (Killa S Smith Richard F, 2008). This increases the turbine efficiency, number of working hours and minimizes the stress on the blade caused by yawing [ ]. Furthermore, the two towers were placed such that they create a ‘V’ shaped space in between them, as well as a negative pressure behind the blocks, thus creating an opportunity for the Venturi effect to accelerate wind velocity onto the turbines (Binder G, 2006) by as much as 30% more than the source wind (Killa S Smith Richard F, 2008). The tapering profile combined with the increased onshore wind velocity at higher altitudes creates a near equal regime of wind speed on each of the three turbines, irrespective of its location, allowing them to rotate at the same speed and generate approximately the same amount of energy (Wood A, 2008). Table 1: Annual energy output Utilisation of Wind Energy for High Rise Building Power Utilisation of Wind Energy for High Rise Building Power Introduction The price of conventional energy is on the rise, due to the ever-widening gap between demands and supply. The main reason for such shortages is the depletion in natural resources, such as coal, which is the main fuel used for electrical energy generation. Since these fuels are made up of carbon compounds, burning them has rapidly increased the amount of carbon dioxide in the atmosphere over the last 100 years. This has brought about a chain reaction of hazards such as global warming, climate change, destruction of ecosystems, etc with predictions for adverse outcomes in the future. In response to this threat and to initiate an end to such processes, the UN agreed the Kyoto Protocol in Japan in 1997. This requires industrialised nations to reduce greenhouse gas emissions by 5% of 1990 levels by 2008-2012. The UK has agreed to meet this target and furthered its promise by setting a goal of 50% reduction in carbon emissions by 2050[ ]. Part of its government energy policy is to increase the contribution of electricity supplied by renewable energy to 10% by 2010 (Blackmore P, 2004). A similar promise has been undertaken by many world nations, which has led to a plethora of new and innovative methods for power generation. Renewable is the key to climate friendly forms of energy, due to the absence of emissions detrimental to the environment (Stiebler M, 2008). It includes energy derived from sunlight, wind, wave, tides and geothermal heat. Out of the afore mentioned resources, geothermal heat is restricted to only limited locations on the globe while wave and tidal power is still in its research stage. Thus sunlight and wind are the key elements that can be tapped for energy generation. However, on comparison between the two systems, wind energy systems are more advantageous both in availability of resources and cost of generation. This report mainly focuses on wind energy, with a keen interest on harvesting it for ventilation and power generation purposes in high-rise buildings. Plan forms that aid this purpose will be studied using Computational Fluid Dynamics to understand the flow of wind in and around a thirty-storey structure and the building configuration well suited for natural ventilation and wind turbine integration would be identified at the end of the test. To obtain a complete picture of wind flow patterns and to closely mimic real life situations, the wind will be simulated from different directions at different wind speeds. Wind energy Wind is the term used for air in motion and is usually applied to the natural horizontal motion of the atmosphere (Taranath Bungale S, 2005). It is brought about by the movement of atmospheric air masses that occur due to variations in atmospheric pressure, which in turn are the results of differences in the solar heating of different parts of the earth’s surface (Boyle G, 2004). At a macro level wind profile differs from place to place depending on geographic location and climatic conditions while in a microstate the immediate physical environment of a particular place modifies the nature of the winds. For example, the velocity of the wind recorded in the countryside which has acres of unobstructed grassland would be greater than that recorded in a city dominated by skyscrapers. Hence to obtain a clear idea of the wind characteristic corresponding to a particular area the wind rose is utilized. They are based on metrological observations and depict the varying wind speeds experienced by a site at different times of the year together with the frequency of different wind directions [ ]. It is the first tool consulted to judge the wind resources of a site and its ability to support power generation. The winds have been tapped from ancient times by means of ship sails, windmills, wind catchers, etc. The history of windmills goes back more than 2000 years (Stiebler M, 2008) when they were predominantly used for grinding grain and pumping water. However, the breakthrough occurred when Charles.F.Brush erected the first automatically operating wind turbine at Ohio in 1888 [ ]. It was fabricated using wood and had a rotor diameter of 17m with 144 blades. The system recorded very low efficiency and was mainly used to charge batteries. The reason behind the poor efficiency was due to the large number of blades, which was later discovered by Poul la Cour who introduced fewer blades into his wind turbine. Though such developments were achieved at an early stage in innovation, it was not until 1980 that the prominent application of renewable energies was sought after (Boyle G, 2004). Wind energy is the harnessing of the kinetic energy prevalent in moving air masses. This kinetic energy for any particular mass of moving air (Boyle G, 2004) is given by the formula: K.E = 0.5mV ² where, m – mass of the air (kg) and V – wind velocity (m/s). However this mass of moving air per second is: m = air density x volume of air flowing per second m = air density x area x velocity   Thus, m = rAV where, r – density of air at sea level = 1.2256 kg/m ³ and A – area covered by the flowing air (m ²) Substituting this value of m in the former equation, K.E. = 0.5rAV ³ (J/s) But energy per unit of time is power and hence the above equation is the power available from the wind. It is also evident that the power is directly proportional to thrice the wind velocity. In other words even a marginal increase in wind speed would yield three folds of the nominal power. This is the critical fact based on which the whole energy process is evolved. However not all of this power can be exhausted since it would lead to nil outflow through the wind turbine, that is no flow of air behind the rotor. This would lead to no flow of air over the turbine causing total failure of the system. According to Albert Betz the maximum amount of power that can be harnessed from the wind is 59.3%. This is often referred to as the Betz limit and has been proven by modern experiments. Some of the advantages of wind energy include: It is based on a non-exhaustive resource and hence can be harnessed for generations. It is a clean and eco friendly way of producing energy. In its working lifetime, the wind turbine produces eighty times the amount of energy that goes into its manufacturing and thus has diminishable net impact on the environment. It does not require any additional resources such as water supply unlike conventional power generation. It can boost the economy of the region (wind farms). Wind turbines: Wind turbines are the modern day adaptations of the yesteryear windmills but unlike their counterparts they are mainly used for power generation. These new age systems come in different shapes and have various configurations, the well established of them all are the Horizontal axis wind turbine and the Vertical axis wind turbine. Write a brief about horizontal wind turbines and vertical wind turbines. BUilding integrated Wind Turbines (BUWT): Building integrated wind turbines are associated with buildings designed and shaped with wind energy in mind (Stankovic S et al, 2009). They are relatively a new way of harnessing energy that is gaining popularity at a quick pace. Small scale wind turbines on house roofs and retrofitting also fall under this category. The design of BUWTs is a complicated affair and involves the careful consideration of various factors. Since turbines are fixed into the building’s fabric its impact on the environment, building’s response and needs of its owners and occupants need to be weighed equally. Also numerous design decisions such as planning, structure, services, construction and maintenance depend on this single process (Stankovic S et al, 2009). With the increase in the scale of the proposal the importance of these factors increases simultaneously. The proposal generally spans from the number, scale, type and location of the turbines together with its annual energy yield and design life. A good BUWT based building should be a wholesome design that does not prejudice the buildings efficient functioning for energy generation. Generic options for BUWTs: Stankovic S et al (2009) explains that the wind turbines can be fixed on to a building in enumerable ways. Each method can accomplish a different level of power depending on the type of turbine used and the form of the building it is mounted upon. On top of a square/ rectangular building: This configuration is on the principle that the wind velocity increases with height and hence the amount of energy generated would be of a higher order (10% increase with wind acceleration). An added advantage is that the turbine would experience relatively little turbulence. But access to the turbine for maintenance and decommissioning works may be difficult. If mounted on tall buildings the turbines may threaten the visual quality of the skyline. On top of a rounded building: This case is very similar to the previous configuration except that with the use of rounded faà §ade the mean tower height can be considerably diminished. Also the rounded profile influences the local acceleration (15% increase in energy). The low tower height favors easy access to the turbine but leads to blade flicker and noise issues. Concentrator on top of a rounded building: This case is well suited to areas with bi-directional winds (20% energy increase over a free standing equivalent due to local acceleration). Vertical axis wind turbines are better suited for this feature while Horizontal axis wind turbines need to be suitably altered to achieve the same status. The building spaces that act as concentrators may be inhabited with suitable acoustical treatment. This case also encounters the same drawbacks as listed in the previous case. Square concentrator within a building faà §ade: As before, this configuration takes advantage of the higher quality winds at higher altitudes and local acceleration thereby achieving 25% increase in energy and 40% increase for bi-directional winds. This option is best suited for buildings with narrower profiles. There may be a loss in the saleable area of the building but the aperture can be converted into an exclusive feature such as a sky garden. The opening also relieves the wind loading on the building’s facade leading to simpler structural solutions. Vertical axis wind turbine is the only choice for integration due to its square swept area. Circular concentrator within a building faà §ade: This is very similar to the square concentrator except the opening is accustomed to hold pitch controlled horizontal axis wind turbines with fixed yaw. Also, a 35% increase for uniform wind and 50% increase in energy for bi-directional winds are achievable in this method. But on the down side, this technique is more expensive due to the cylindrical shroud. On the side of a building: In this technique, an increase in 80-90% in energy than the freestanding equivalents is achievable only if the building form is optimized to the local wind character. Only reliable vertical axis wind turbines can be used for power generation due to access issues. For higher swept area, more number of turbines should be used. Between multiple building forms: This type of an option opens out many doors for a range of architectural forms. Unlike the previous cases, the buildings orientation, form, shape and spacing play key roles in the performance of the turbines. Vertical axis wind turbines are better suited for this purpose. Guidelines for BUWT’s: The following are some guidelines outlined by Stankovic S et al (2009) for incorporating wind turbines into a structure: BUWTs should be tailored to the specific site for good results. Adequate wind resources should be available on site. If however if the site is under resourced steps are to be adopted to deliberately elevate the quality of the wind through the buildings form or turbine. The impact of its surroundings should also be considered before commissioning such a project. The dominating wind direction and its intensity should be observed from meteorological data. This would help in determining the form and orientation of the building together with finalizing the position of the wind turbine to make the most out of the available resource. Environmental impact assessment corresponding to the site should be carried out to foresee the adverse effects the turbines may create. Acoustic isolation may be sought for in some areas within the building if it lies at close proximity to the rotor. Natural ventilation and day lighting qualities of the building may be challenged and forced to settle for artificial means. The type and position of openings, external shading devices, smoke extracts etc should be handled with appropriate care to avoid draught winds. Access to the wind turbines for maintenance and decommissioning must be provided suitably. The aesthetic quality of the mounted turbines must harmonize with its surroundings and should not over power the pedestrians at ground level. To this end well suited screening devices such as canopies, screens and landscape may be utilized as per the necessity. The overall success of BUWT project depends on its ability to deliver the expected power. Inability to comply with this effect would result in the failure of its intended purpose from both an environmental and design point of view. Thus the electricity demand of the building and the level to which this would be met with should be estimated prior to turbine design to secure maximum benefits. Wind flow prediction and energy yields: For any project to be successful, Wind flow and building design (Taranath Bungale S, 2005) When the air moves in a vertical direction it is referred to as a current. These currents play a major role in meteorology whereas the gradual decrease in wind speed and high turbulence of the horizontal motion of air, at the ground level, are vital in building engineering. In urban areas, this zone of turbulence extends to a height of approximately one quarter of a mile aboveground and is called the surface boundary layer. Above this layer, the horizontal airflow is no longer influenced by the ground effect. The wind speed at this height is known as the gradient wind speed, and it is precisely in this boundary layer where most human activity is conducted. Characteristics of wind: The flow of wind is complex because many flow situations arise from the interaction of wind with structures. A few characteristics of wind include: Variation of wind velocity with height: The viscosity of air reduces its velocity adjacent to the earth’s surface to almost zero. A retarding effect occurs in the wind layers near the ground, and these layers in turn successively slow the outer layers. The slowing down is reduced at each layer as the height increases, and eventually becomes negligibly small. The height at which velocity ceases to increase is called the gradient height, and the corresponding velocity, the gradient velocity. At heights of approximately 366m aboveground, the wind speed is virtually unaffected by surface friction, and its movement is solely dependant on prevailing seasonal and local wind effects the height through which the wind speed is affected by topography is called the atmospheric boundary layer. Wind turbulence: Motion of wind is turbulent and it occurs in wind flow because air has a very low viscosity-about one-sixteenth that of water. Any movement of air at speeds greater than 0.9 to 1.3 m/s is turbulent, causing air particles to move randomly in all directions. Vortex shedding: In general, wind buffering against a bluff body such as a rectangular building gets diverted in three mutually perpendicular directions. However, only the longitudinal winds and the transverse winds or crosswinds are considered in civil engineering. When a free flowing mass of air encounters a building along its path, the originally parallel upwind streamlines are displaced on either side of the building. This results in spiral vortices being shed periodically from the sides into the downstream flow of the wind, called the wake. At relatively low wind speeds the vortices are shed, that is, break away from the surface of the building and an impulse is applied in the transverse direction. Distribution of pressures and suctions: When air flows around the edges of a structure, the resulting pressures at the corners are much in excess of the pressures on the center of elevation. This has been evident by the damages caused to corner windows, eave and ridge tiles, etc in windstorms. Wind tunnel studies conducted on scale models of buildings indicate that three distinct pressure areas develop around the building. They are: Positive pressure zone on the upstream face (Region 1) Negative pressure zone at the upstream corners (Region 2) Negative pressure zone on the downstream face (Region 3) The highest negative pressures are created in the upstream corners designated as Region 2. Wind pressures on a buildings surface are not constant, but fluctuate continuously. The positive pressure on the upstream or the windward face fluctuates more than the negative pressure on the downstream or the leeward face. The negative pressure region remains relatively steady as compared to the positive pressure zone. The fluctuation of pressure is random and varies from point to point on the building surface. Nearby buildings can have a significant influence on wind forces. If they are the same height as the structure being considered then they will mostly provide shelter, although local wind loads can be increased in some situations. Where surrounding buildings are significantly taller they will often generate increased wind loading (negative shelter) on nearby lower structures. Shelter can result from either from the general built-environment upwind of the site or from the direct shielding from specific individual upwind buildings (Blackmore P, 2004). Natural ventilation The three natural ventilation airflow paths in buildings are (Pennycook, 2009): Cross ventilation Single-sided ventilation Passive stack ventilation Advantages of cross ventilation: Greater rates of ventilation can be achieved under amicable weather conditions. Can be utilized for deep-plan spaces with operable windows on the external wall. Incumbents have control over ventilation. Relatively cost free. Can be incorporated with thermal masses. However, it has certain limitations such as: Internal space layout must be hindrance free for easy, clear flow of air. Internal partitions must be within 1.2m height and tall cupboards must be placed alongside the windows. Natural ventilation can occur only under the presence of suitable winds. Poor planning and positioning of windows may cause disruptive draughts and gusts. Winter ventilation is problematic. Unsuitable for buildings located in noisy and pollution prone environments. The requirements of fresh air supply are governed by the type of occupancy, number and activity of the occupants and by the nature of any processes carried out in the space (Koenigsberger et al, 2001). When natural ventilation is stipulated for good indoor air quality, the amount and nature of the dominant pollutant source in the space should be identified. Based on this data the ventilation rate for the space can be calculated such that the pollution level does not cross a preset specific mark. Generally the concentration of the pollutants decreases with the increase in airflow rate (Figure –1). However, in terms of thermal comfort especially during winter the heating requirement of the building will increase with the ventilation rate. This demand varies with time, wind characteristics of the place, opening and closing of windows and doors by its occupants and the thermal state of the building. In summer, cooling is ideal for both the building and its occupants to prevent internal heat gains. By directing the high velocity wind around the human body the evaporative rate at the skins surface can be increased thereby achieving a cooling sensation. The recommended upper limit of indoor air movement is 0.8 m/sec, which permits the inhabitants to occupy a space about 2 °C warmer and 60% relative humidity with optimum comfort. The traditional way to cool buildings is to provide large openings along the exterior wall with the principle that higher the ventilation rate greater the loss of heat to the external environment. But such an arrangement would work only when the outdoor te mperature is in the range of comfort zone. When controlled indoor environments are desired especially during the occupancy period’s night ventilation is recommended. In this technique the building is cooled at night so that it can absorb the heat generated during the day (Allard F, 1998). Based on wind tunnel experimental observations, the factors that affect the indoor airflow are: Orientation: External features: Cross-ventilation: Position of openings: Size of openings: Control of openings: Literature review The following are studies that have been made of different aspects of wind using Computational Fluid dynamics. CFD evaluation of wind speed conditions in passages between parallel buildings: This analysis undertaken by Blocken B et al (2007) mainly focuses on the wind speed conditions in passages between parallel buildings in combination with the accuracy of the commercial CFD code Fluent 6.1.22 when the wall-function roughness modifications are applied to them. The Venturi effect is also studied to determine the amount of increase in wind speed in the passage due to the decrease in flow section. The results obtained were compared with various previously proven experiments carried out by experts in the field. As the title indicated the case undertaken involves a pair of rectangular buildings measuring 40m x 20m x 20m, placed adjacent to each other and separated by a narrow passage. The width of the passage is widened (for example, 2, 4, 6, 8, 10, 15, 20, 30, 40, 60, 80, 100 m) with every case to clearly understand the Venturi effect. The dimension of the computational domain is 20.5x14x18m3; the whole setup is placed at a distance of 5m from the inlet and simulated with a wind speed of 6.8m/sec based on initial results. The results recorded at the end of the simulation process are discussed as follows. They are based on the amplification factor, which is defined as the ratio of the mean wind speed at a certain location to the mean wind speed at the same location without the buildings present. As such it is a direct indication of the effect of the buildings on the wind speed (Blocken B et al, 2007). Pedestrian level wind profile: In context to this research, for narrow passages (example w=2m) this amplification factor occurs maximum at the centerline immediately behind the entrance. When the distance between the buildings are slightly increased (example w=10m), the flow streams deflecting off the inner edges of the buildings combine into a large jet stream and records an increase in the amplification factor. However this property is lost when the width of the passage is of a high order (example w=30m). Overall wind profile: To understand the overall wind profile, six vertical lines were identified along the passage’s center plane for the case of w=6m. The lines depicted the fact that there was an increase in the wind speed at the ground level due to the downdraft of the wind along the front faà §ade of the building and a decrease in wind speed at the end of the passage due to the exit of flow from the passage. Also for these cases, there was no significant increase in the wind speed with the increase in height. Flow rates at different points in the passage: To evaluate the Venturi-effect three fluxes were defined, one along the vertical plane, another along the horizontal plan and the final being similar to the former one but in the absence of the buildings. When the flow rate was calculated for narrow passages, it stated an increase in wind speed by only 8% due to the Venturi effect. However for larger widths the flow rate was lower than the free-field flux. This shows that the wind has a tendency to flow over and around the building rather than be forced through the passage as previously believed. Thus there is a lack of strong Venturi effect and the flow in the passage can be attributed as the channeling effect for these cases. The research also concluded that there were discrepancies in the CFD results due to the use of the roughness factor and advised future users to simulate an empty field before positioning the buildings to clearly identify the difference in results. Further research into the Venturi effect was also implied. Computational analysis of wind driven natural ventilation in buildings: Evola G and Popov V (2006) research focuses on the application of three-dimensional Reynolds Averaged Navier-Strokes (RANS) modeling on wind driven natural ventilation with specific detail to the pressure distribution and flow pattern within the building. The various cases would be simulated with the standard k-e model and the Renormalization Group theory (RNG). Within the framework of natural ventilation both single sided ventilation and cross ventilation would be studied and the results obtained using CFD will be compared with LES models and empirical methods for its reliability.  Ã‚  Ã‚   The building undertaken consists of a 250mm x 250mm x 250mm cube punctured with a centrally located 84mm x 125 mm opening on the wind ward side (Case 1). In Case 2 the door like opening is placed on the leeward side and in Case 3 both the openings are retained to test the cross ventilation principle. On comparison between the CFD results obtained for Case 1 and 2, Case 2 portrays a better flow pattern especially at the mouth of the opening. This leads to a better ventilation rate than Case 1 though in contrast to the theoretical data that good ventilation rate and flow patterns are achievable only when the opening faces the incoming winds. To establish the phenomenon further experimentation into the field was suggested. Between Cases 1, 2 and 3, cross ventilation clearly stands out as the best option of them all, both in terms of velocity and distribution. Also the study concluded that the measured RNG results matched approximately to the theoretical results of Cases 1 and 2. But a significant amount of deviation was observed in Case 3. The RNG model was only slightly intense than the k-e model generally used. The research also concluded that there were discrepancies in the CFD results due to the use of the roughness factor and advised future users to simulate an empty field before positioning the buildings to clearly identify the difference in results. Further research into the Venturi effect was also implied. CFD modeling of unsteady cross-ventilation flows using LES: This research undertaken by Cheng-Hu Hu et al (2008) employs the LES method to investigate the fluctuating ventilation flow rate induced by the wind for a cross-ventilated building. The results from CFD were compared with those previously acquired from wind tunnel tests.   Ã‚   The building proposed for the study consists of a rectangular box with two openings of equal size located opposite to each other. The wind is simulated from 0 °(Case 1) and 90 °(Case 2) to the building at a rate of 1m/sec, to study the flow pattern in and around it. When the air approaches the building the ventilation rate is unsteady at the mouth of the openings due to turbulence and in the flow separation layer due to shear. In Case 1 the wind is accelerated through the opening and directed downwards inside the building. This phenomenon brings about a circulation of the internal air before guiding the wind upwards and out through the window on the leeward side of the building. The air exchange occurs due to the mean flows through the opening. In Case 2 where the wind is parallel to the windows, the air moves in and exits rapidly causing fluctuating flows thereby leading to air exchange. In this case turbulence prone areas are formed at the rear of the building. When these results were compared with the wind tunnel data, Case 1 portrayed similarities while Case 2 had major deviations. Further study was proposed for understanding the reason behind such deviations. Case studies The Bahrain world trade centre was the world’s first building to ‘aesthetically incorporate commercial wind turbines into the fabric of the building’ [ ]. The complex consists of a three-storied sculpted podium and basement from where the 240m high towers rise up into the sky. The two towers comprise of 51 floors each and are connected by means of three, 31.5m span bridges at 60m, 96m and 132m levels [ ]. They are oval in section for aerodynamic reasons and follow a shallow V-shape in plan for adequate blade clearance. Sitting on each of this 70 ton spandrel is an 11-ton nacelle to which the industry approved horizontal axis wind turbines are fixed by special means. The turbine has a rotor diameter of 29m and is stall controlled with centrifugally activated feathering tips for air brakes (Killa S Smith Richard F, 2008). The turbines are oriented facing the Arabian Gulf intercepting the path of the dominant winds. The decision to harness the prevailing wind was thought of from the initial stage drawing inspiration from ‘the regional wind towers and the vast sails of the traditional Arabian Dhow which utilise the wind to drive them forward’. Numerous Computational fluid dynamics models and wind tunnel tests were carried out to determine the final building form. The result was a skyward tapering, elliptical structure, carved out by the wind that functions as aerofoil sections (Wood A, 2008). The shape and spatial relationship of the towers aid in adhering the wind in a â€Å"S’ flow whereby the center of the wind stream remains nearly perpendicular to the turbine within a 45 ° wind azimuth, either side of the central axis (Killa S Smith Richard F, 2008). This increases the turbine efficiency, number of working hours and minimizes the stress on the blade caused by yawing [ ]. Furthermore, the two towers were placed such that they create a ‘V’ shaped space in between them, as well as a negative pressure behind the blocks, thus creating an opportunity for the Venturi effect to accelerate wind velocity onto the turbines (Binder G, 2006) by as much as 30% more than the source wind (Killa S Smith Richard F, 2008). The tapering profile combined with the increased onshore wind velocity at higher altitudes creates a near equal regime of wind speed on each of the three turbines, irrespective of its location, allowing them to rotate at the same speed and generate approximately the same amount of energy (Wood A, 2008). Table 1: Annual energy output

Binge Drinking on America’s Campuses Essay -- College Alcohol Abuse

Binge drinking is rampant on today’s colleges and university campuses. Binge drinking is defined as, five or more drinks for a man at any one time, four or more drinks for a woman (Thompson, J.J. 63). A recent survey revealed that almost half of college students engage in binge drinking, and half of those who binge drink do so regularly (McCormick, John; Kalb, Claudia 89). It is not the half that drinks responsibly that needs programs targeting them; it is the other half of students that engage in binge drinking. This paper aims to discuss both the scope of binge drinking on the campuses of America’s colleges and universities and techniques used to combat it. At the same time America has managed to keep the same percentage of its students from drinking entirely for the last five years, binge drinking has been on the rise (Thompson, J.J. 63). While 49 percent of college students binge, only 28 percent of their non-college counterparts do (McCormick, John; Kalb, Claudia 89), clearly illustrating the divide that exists between students and non-students. These figures are upsetting in that one would expect universities to be the breeding ground for new leaders and innovative thinkers in society while these figures make today’s college campuses look like nothing more than National Lampoon’s Animal House- a drunken debauchery. Consider these facts: For women, this study found that 80% of sorority house residents had binged during the last 2 weeks prior to this study compared with 58% of non-resident sorority women, and 35% of non-Greek women. As for the men, the study found that during the previous two weeks, 86% of fraternity house residents had binged compared to 71% of non-resident fraternity men and 45% for non-Greek men (Core Institute pars. 1-2). If there has ever been a clearer cut case for reformation of the Greek system, it has never been presented. This problem was tragically brought to light in 1996 with the media attention given to the death of a Louisiana State University student who died in the fraternity house from acute alcohol poisoning. Tragically, the numbers of students dying of alcohol related causes are rising steadily each year. With the ever increasing costs of higher education, one would think that students would be committed to gaining the best education possible; but a 1996 study leaves little doubt that a student’s GPA ... .../collfact.htm Colleges and Drinking. CNN Online. February 23, 1999. http://cnn.com/US/9805/02/campus.crime/index.html New Study Finds Bingeing. Core Institute. September 1, 1999. http://www.alphaomicronpi.org/Article/alcohol02.html Drugs- Indiana University. Indiana University. February 23, 1999. http://www.drugs.indiana.edu/publications/ncadi/primer/binge.htm Iowa State Daily. February 2, 1999. http://www.daily.iastate.edu/volumes/Fall95/Dec-01-95/fr3-hw.html LA Times Website. February 28, 1999. http://peele.sas.nl/lib/latimes030196.html McCormick, John; Kalb, Claudia. â€Å"Bellying Up to the Bar; binge drinking remains a major problem on many college campuses, according to a Harvard University study.† Newsweek 21 September 1998: 89. New UNC Initiave. February 28, 1999.http://www.cspinet.org/new/aluncorn.htm Thompson, J.J. â€Å"Plugging the Kegs: students benefit when colleges limit excessive drinking; alcohol abuse by college students.† US News & World Report January 1998: 63. Internet Sources Consulted Wechsler, Henry PhD. Binge Drinking on America’s College Campuses. Harvard http://archive.sph.harvard.edu/cas/Documents/monograph_2000/cas_mono_2000.pdf

Black Panther and Ku Klux Klan Essay

After doing research to compare/contrast the two groups, the Black Panthers and the Ku Klux Klan, it opened my eyes. I realized that the new generation is oblivious to the existence of both groups and the similarities and differences in them. I researched the two different groups to see when the groups came into existence who were the members, why they fought for rights they thought they deserved and the group’s involvement in violent acts and their remnants today. In World War II, blacks fought for the American dream willingly, but separately from the white soldiers. When the war was over, human rights activists of all races and educated blacks thought the soldiers and blacks deserved the right of equality. Malcolm X was one of the many human rights activists. He was an African-American Muslim minister he thought after years of non-violence, signing petitions, marching, praying and crying and blacks doing the impossible to be recognized as human beings, it was time for them to take it into their own hands. Malcolm X was then assassinated February 21, 1965. Today many of his quotes like this one are famous. â€Å"And when I speak, I don’t speak as a Democrat. Or a Republican. Nor an American. I speak as a victim of America’s so-called democracy. You and I have never seen democracy – all we’ve seen is hypocrisy. When we open our eyes today and look around America, we see America not through the eyes of someone who has enjoyed the fruits of Americanism. We see America through the eyes of someone who has been the victim of Americanism. We don’t see any American dream. We’ve experienced only the American nightmare.† The Black Panther Party was then founded by Huey P. Newton and Bobby Seale,  in 1966, it was based on ideas which were strongly associated with Malcolm X’s life works it was made up of progressive militant political organization. They advocated Black Nationalism and had strong believes in the necessity of violence and armed self-defense. They patrol African American neighborhoods to protect residents from acts of police brutality and to obtain freedom from white oppression. Fought for the rights of American blacks in the US, they called themselves â€Å"Revolutionaries†. Ku Klux Klan on the other hand was founded in 1866 in Pulaski, Tennessee. The Klan members were many former Confederate veterans determined to fight for the right to restore white supremacy they called themselves â€Å"The Invisible Empire of the South†. Ku Klux Klan believed that black weren’t fighting for right but for special right and that Negros were happier when they had nothing not even their own name. They also showed resistance to policies that gave the right to economic equality for blacks and other minorities. The Black Panthers were non-violent they petitioned for the right for Black Americans to bear arms. Reason being the police weren’t there for their safety or to promote their welfare they were there to contain, brutalize and murder them. With the blacks starting to carry guns came violence. There were shootouts with police which killed many innocent people, riots that destroyed towns, blacks had means to defend themselves but then crime skyrocketed. The Black Panther weren’t organized as some thought and weren’t ready to fight a revolution they just wanted to be treated like an equal and were ready for anything that crossed there path. Ku Klux Klan had and still have a very violent disposition, they could terrorized the black and any other minorities that they thought threatened their white purity as they referred. Being that the sheriff upheld the rights of the Klan and courts upheld the rights of the sheriff. The Klan killed civil right helpers’ blacks and whites. Civil rights helpers assisted blacks learn to read so that they could vote as well as getting them to the poles to vote. KKK burned many churches, schools and were involved in lynching of hundreds. Now after two decades of failure 1982 was the official end of the Black Panther Party they did accomplish one thing a major change in police brutality in Oakland went way down. Black Panther also went back to square one the non-violence approach, by setting up organization to help needy family such as free clinic and free meal programs. Educated blacks and activist in this generation are very disappointed in blacks not getting involved and how they accept the minimum for themselves. KKK on the other hand are still very prominent and doubled in size. They even still to this day try to recruit new members by putting flyers with candy on doors in residential areas, doing pod cast, and even do interviews to try to convince the public what they are doing is right and isn’t racist as all. They are even trying to adopt highways in some states which judges aren’t allowing, even after they try to convince them it’s to keep nature clean.

Berkshire Threaded Fasteners Case Essay

Berkshire Threaded FastenersBerkshire Threaded Fasteners Company has recently lost their president, John Magers. The resulting appointment of his inexperienced son Joe Magers has lead to the company’s loss of confidence. Brandon Cook is the recently appointed general manger who was hired to turn the company around after a loss of $70,000 in a good business year. As a member of an outside consulting firm I have been called in to give advice on the problems the company is facing. The time period has been updated to the present times. Manufacturing ProcessSee Appendix A for the detailed manufacturing process. In short, fasteners begin as wires, rods and bars which are then cut to length, headed and finally threaded. What should be noted is that this particular manufacturing process called cold forming is high-speed, high-volume, economical and has low wastage. Such economies of scale will allow Berkshire to offset the very high costs of cold-forming equipment. Business StrategyA careful analysis is needed in order to determine Berkshire’s business strategy. At first one would think it was product differentiation because of the inelastic demand in the short run. But one thing that should also be noted is the fact that for most goods, demand is much more price elastic in the long run than in the short run. This combined with the fact that Berkshire is convinced that it could not individually raise prices without suffering substantial volume declines, and that all the products of the different manufacturers in the industry are very similar, prove that their business strategy is in fact cost leadership. Another piece of evidence that also supports this strategy is the fact that the major focus of their accounting system seems to be on cost reduction. Place in the EconomyThe industrial fastener industry has been experiencing modest growth since the 1990s with an average per annum revenue growth rate of 3.6% ; though the number of employees have remained relatively the same. The North American fastener industry is still expected to grow by around 4% annually despite the competition from foreign countries. However this number represents a decline from the 9% growth spurt which occurred in 1998. The North American fastener production is strongly tied to the production of automobiles, aircraft, appliances, agricultural machinery and equipment, and the construction of commercial buildings and infrastructure. The more these industries prosper, the greater the demand and prospects for the fastener will there be. There has been as ever expanding market for fasteners in the 21st century in the aerospace industry. In fact a 9% annual growth in fasteners for this industry can be expected. Motor vehicle sales have also increased by 9.6% from 2005 to 2006. Unfortunately housing starts have only increased by 0.7% from 2005. In the future analysts expect metal fasteners to face competition from the adhesives industry as more products are being made with plastic, a product best joined together by adhesives. Also buyers have now been demanding innovative and diverse fasteners which are also more environmentally friendly- fasteners that maintain lubricity without the use of cadmium, a suspected carcinogen. So the industry is slowly shifting its focus to more highly engineered, technologically advanced fasteners. SWOTStrengths:1) Newly appointed Brandon Cook has wide executive experience in manufacturing products similar to that of Berkshire. 2) Berkshire operates in a capital intensive industry. But as a percentage of total sales, Berkshire’s labour costs are 24.69%. This suggests that they either still retain their employees even when they could have done without them or that they pay very high salaries to a few workers. This shows that Berkshire has either very loyal employees or very skilled employees- both being assets. Weaknesses:1) Joe Magers is not very experienced and the company is facing losses in the production of the 200 and 300 series’. 2) As a percentage of total sales, Berkshire’s fixed costs are 47.37%. This is much higher than what a price competitive manufacturer like Berkshire should have had. 3) Berkshire pays 49% of all its wages and salaries to administrative and sales employee, when the industry average is 27% . This shows poor decision making processes of the firm. Opportunities:1) If product lines are discontinued, with the excess capacity and skilled labour force they can branch out into the production of more diverse fasteners. This ties in with the fact mentioned previously that buyers are now demanding more specialized products. Threats:1) Berkshire operates in an industry where a few of its competitors are much larger. 2) The industry is dominated by Bosworth who dictates the prices that are charged for fasteners. 3) Buyers are slowly demanding more specialized fasteners. ProblemWhat is very evident is that the company is losing money on its products. In the previous time period they had incurred a loss of $70,000. Berkshire is unsure if it is the result of the production of the 300 series or the pricing decisions of the 100 series. These alternatives need a careful analysis in order to make informed decisions that will help turn the company around. Alternative #1 Status QuoQuantitative Analysis:In order to determine if the company should â€Å"do nothing,† is to predict the future cash flows and net income (loss) for the second half of the year. See Appendix B for this calculation. The predicted net income is in fact a loss of 1134. Yet, net income may not be a faithful representation, so cash flows have also been calculated. The predicted cash flow is a negative amount of 388. These amounts while better than alternative #3 (drop the 300 series) is not as good as the cash flow and net income amounts for alternative #2 (reduce price levels of the 100 series). One very important thing that needs to be noted is the fact that variable costs are indeed relevant. Fixed costs remain constant even after the production is stopped, but variable costs increase and decrease with production. Therefore the total contribution margin for this alternative was calculated to be 1504 which does show this alternative in a better light  especially when in comparison to its net loss and cash flow figures. Qualitative Analysis:The reduced production of the 100 series as a result of the price level remaining the same will have a significant impact on Berkshire. The reduced production may lead to employees worrying about the fact that they may be laid off to such an extent that their productivity is significantly lowered. Berkshire could also develop a reputation of charging higher prices than the industry standard and they could end up loosing more and more buyers to competitors. Alternative #2 Change price level to $2.25 for the 100 seriesQuantitative Analysis:In order to determine if the price level needs to be dropped a few calculations are needed. First a prediction of its impact on the net income and cash flows for the second half of the year is needed. These calculations are shown in Appendix C. The predicted net income figure is a loss of 1035. The predicted cash flow is a negative amount of 289. While these figures do seem abysmal, what should be noted is that in comparison to the other alternatives, these figures are much better. Both the net loss and negative cash flow amounts in this alternative is 99 lower than the â€Å"status quo† alternative and 338.58 lower than the â€Å"drop 300 series† alternative. This hints to the fact that maybe the price should in fact be dropped. Another fact that backs this assertion up is in the calculation of the Contribution Margin (CM) for both price levels, based on data from the first half of the year. Table 2 in Appendix A shows this calculation. While the CM of the new price level is lower than that of the original level (0.96 vs. 1.16), the fact that they will sell 250,000 units more (and hence a higher total CM for the new price) clearly makes up for this difference. The success of the new prices level will be contingent on the number of units sold. What is very dangerous about this alternative is that if in the future the demand in the market for this product line slumps, only a very small amount of money will be available to be used to pay off the fixed costs. Qualitative Analysis:The change in price level will not have much of an effect on the employees of Berkshire because they would still be producing  around the same amount of units (1000000 vs. 996859). They would not have to worry about being laid off. What will be affected is Berkshire’s reputation. If they had not changed they would have developed a reputation of charging high prices. The reduction of the price would put them at par with Bosworth. Alternative #3 Drop 300 seriesQuantitative Analysis:In order to determine if the 300 series needs to be dropped a few calculations are needed. First a prediction of the impact of its removal on the net income and cash flows for the second half of the year is needed. The predicted net income figure is a loss of 1373.58 and the predicted cash flow is calculated to be a negative amount of 627.70. The net loss figure calculated is the highest loss of all three alternatives and the negative cash flow amount is also much higher than the alternatives as well. This hints to the fact that maybe the 300 series line should not be dropped. Also, if the 300 series had been dropped at the beginning of the year it can be seen that there would have been a loss of -183. See the calculations for these numbers in Appendix D. Another aspect that backs up this assertion is the calculation of the Contribution Margins for all three product lines based on first half information. Even though Berkshire incurred a loss of .22/unit in the first half for series 300, when you calculate the CM it is a whole new story- the CM of 300 is a positive number- 1.15/unit, this means that Berkshire would in fact incur an even greater loss if they chose to halt production. The 1.15 per unit would no longer be available to cover some of the fixed costs. What is also surprising is the fact that the 300 series Contribution Margin is not far behind from that of the 100 series (the most profitable product line) and equal to that of the 200 series. A few other very important observations also need to be taken into account. First, since many products do cover all their variable costs, no product line would ever be dropped if only a contribution margin analysis were conducted. Second, even though the 300 series covers its variable costs and part of its fixed costs, it proves to be below par when considering full costs. Finally, in the long run all costs are variable, so the 300 series in this time frame is in fact a poor product line. Qualitative Analysis:If the 300 series was dropped it would have a significant qualitative impact on Berkshire and its employees. All the employees who were involved in the production of this line would either have to be laid off (which would have a negative impact on the reputation of the firm), or they could still be retained (which would lead to them obtaining a deep sense of respect and loyalty to the firm). Also the employees who would be shifted around would gain a greater skill set and hence become very valuable assets to the company. Evaluation of the alternativesComparison Table1) Profitability2) Timeliness3) Consistency with Strategy. Alternative #1-$11347 daysNot as muchAlternative #2-$10354-7 daysYesAlternative #3-$137410-14 daysNot as much1) Profitability:The primary objective of all businesses, no matter how big or small, is profit. That is why as a criterion, Profitability was given the number one rank. The three alternatives can easily be evaluated on this criterion by comparing the net income figures. Alternative #2 easily wins in this criterion. Despite the fact that it does have a net loss, the loss was not as great as that of Alternative #1 and #3. One important thing that should be noted is the fact that perhaps the second half of the season is always a slow period and that is why the net income figures are so low. 2) Timeliness:Berkshire operates in a business environment where if firms that lag behind in decision making, implementation of policies etc, they will be left behind with no profits. That is why Timeliness was given the rank of two. Surprisingly Status Quo would have an implementation time of around 7 days. Since keeping the price level of the 100 series the same at 2.45/unit would result in them producing 385332 less number of units (See Appendix E for the calculation), time would be need to shift employees around to new jobs in the firm, possibly close down a warehouse or even convert the machines used to produce the 100 series to now produce a different product line. Alternative #2, â€Å"reduce price level† would probably only take 4-7 days to implement. The only thing Berkshire would need to do would be to inform their current buyers of their new price level and perhaps also to advertise the lower price in a specialized fastener industry journal. Alternative #3, â€Å"drop the 300 series† would probably take around 10-14 days. Not only would Berkshire need to shift employees around, close down a warehouse etc, as a result of producing a lower number of 100 series units, but they would also have to announce the dropping of the 300 series line to its buyers, move even more employees around (or possibly lay them off), close even more warehouses down, move machinery around the manufacturing space etc. This would be a very time consuming process. Overall Alternative #2 would win in this criterion as it would have a less time consuming implementation time and process. 3) Consistency with Strategy:This criterion was given a rank of three because while necessary in the evaluation, Profitability and Timeliness do have a greater importance. In the short run Alternative #2 had the greatest consistency with strategy. Berkshire is a cost leader, and reducing the prices of the 100 series ties in very well with this strategy. Alternative #1 and #3 chose not to reduce the price and this decision conflicts with their cost leadership strategy. ConclusionOverall I would recommend that Berkshire implement Alternative #2- reduce the price level of the 100 series, as it did win in all three criteria. But one important thing needs a re-mention. The CM per unit of the reduced price level was lower than that of the higher price level. It was only because of the higher volume of sales did it manage to have a higher total contribution margin. In the future if sales volumes drop, despite the price change Berkshire would incur heavy losses. At this present time Alternative #1 and #3 are both very unprofitable and will still be in the future. At least Alternative #1 is not as unprofitable at this present time but what happens in the future will all depend on sales. Recommendations for Specific Action1) Chose a date when the price change will come in to effect and make sure all current buyers are aware of this well ahead of time. 2) Advertise in newspapers, journals etc to get the message across to new buyers that Berkshire has reduced its prices. 3) All forms, documentation, accounting systems etc should be changed to take into account the new price level. 4) Make sure that there are people at hand to research the market and evaluate whether demand is going to decline for the 100 series. 5) Make sure that there are researches available to study the market for new trends and new types of fasteners that could be produced in the future.

Costo de un abogado migratorio en Estados Unidos

Costo de un abogado migratorio en Estados Unidos Lo que puede costar  un abogado de migracià ³n en Estados Unidos depende del estado, de la clase de tramitacià ³n, del tipo de contrato, de su fama, etc. Este artà ­culo informa sobre honorarios promedio que cobran los abogados migratorios por tipo de trmites pero tambià ©n sobre causas para entender las grandes diferencias en los costos y las distintas formas de trabajar de los letrados en Estados Unidos que pueden afectar al monto final de los servicios. Factores que influyen en los honorarios de abogados de migracià ³n El monto de lo que cobra un abogado depende de varios factores, empezando por la dificultad de cada caso ya que no todos son iguales y los ms complejos son los ms caros. Otro factor a tener en cuenta es la ubicacià ³n de la oficina del letrado.  Hay una gran diferencia entre lo que se puede cobrar de un estado a otro, incluso dentro del mismo estado, de un pueblo a una ciudad grande. Asimismo debe tenerse en consideracià ³n el tipo de contrato entre el cliente y el letrado.  Por un lado hay  abogados que cobran por hora  un costo que puede ir entre $100 y $500. Por el contrario otros letrados cobran una cantidad fija segà ºn el tipo de tramitacià ³n. Esto à ºltimo es muy comà ºn entre abogados de inmigracià ³n. En algunos casos, por ejemplo, en las peticiones de una tarjeta de residencia para un familiar, es posible un acuerdo entre abogado y cliente, de tal manera que se paga una cantidad inicial al principio y cuando va avanzando el caso se paga el resto del dinero. Si este es el caso hay que tener muy claro cunto se paga y en quà © momento. Los gastos escondidos pueden incrementar enormemente el costo final de un trmite.  Por ejemplo, a la hora de cerrar un acuerdo con un abogado hay que tener muy claro si actividades extras como acudir a corte, visitar un detenido, etc, estn incluidos o hay que pagarlos a mayores. Y en este caso, cul serà ­a el costo. Los desplazamientos a centros de detencià ³n pueden ser carà ­simos, por eso en este caso preguntar si es posible que el abogado consulte con el detenido por telà ©fono.  Incluso hay que saber si se paga a mayores por traducciones, fotocopias, preparacià ³n de entrevistas etc. Preguntar explà ­citamente si en el precio que se paga van incluidas cosas como hablar con el USCIS si estos dicen que no se ha recibido un documento que se ha enviado. Responder a un RFE, es decir, presentar ms evidencias cuando Inmigracià ³n asà ­ lo pide, etc. Adems, la buena fama de un despacho de abogados con un amplio rà ©cord de casos ganados en su especialidad le permite cobrar ms que la media de sus compaà ±eros de profesià ³n. Finalmente es muy importante tener en cuenta que en los precios que cobran los abogados por sus servicios no estn incluidas las cuotas (fees en inglà ©s ) que hay que pagarle al USCIS o en su caso a un consulado. Esas cuotas se abonan a mayores (verifica si puedes calificar para no hacer el pago de la cuota). Listado de precios medios que cobran los abogados de inmigracià ³n Consulta: puede ser gratuita, pero es muy comà ºn cobrar a partir de $100. Tambià ©n es posible que se cobre menos si es por telà ©fono y ms si es presencial. Y que se limite el tiempo de la consulta, por lo que es importante ir preparado y saber todo lo que se quiere preguntar.Visa de fiancà © (prometido de ciudadano): una gran variacià ³n, desde $340 a $2.000Renovacià ³n, extensià ³n de una visa B1/B2 (turista, paseo o placer): $300-$2.000Visa de turista: $500 a $1.000DACA o Accià ³n diferida para Dreamers: de $200 a $500. Incluso $1.000 en casos complicados. Hay numerosas organizaciones sin fines de lucro que brindan estos servicios gratuitamente a los muchachos que califican para la renovacià ³n de la Accià ³n Diferida.Formulario N-400 para solicitar la ciudadanà ­a americana por naturalizacià ³n: $400-$1.000 y ms si hay complicaciones o es una aplicacià ³n que se hace a los tres aà ±os de recibir la residencia.Visa TN para profesionales mexicanos: a partir de $500V isa J-1, no objection waiver: $500Visa J-1, otras clases de waiver: a partir de $3.000 Visa P para atletas o deportistas: $3.000Preparacià ³n de entrevista: $300 y msMocià ³n para reabrir un caso: $3.000Peticià ³n de los papeles para un familiar (I-130): entre $500 y $1.800. Remocià ³n de condiciones de tarjeta de residencia por matrimonio: $500Ajuste de estatus: $600-$ 2.500I-90 para reemplazar la tarjeta de residencia: $500Permiso de trabajo: $350-$400Perdà ³n por inadmisibilidad 212(d)(3), para no inmigrantes que no pueden obtener visa por razones como salud, prostitucià ³n, ciertos rà ©cords criminales, contrabando de personas o presencia ilegal. $1.000-$2.000Perdà ³n (waiver) 601 o el 601A- ms de $4.000Visa H-1B: $900-$1.000 sin el certificado de trabajoLabor certification Perm: $5.000Visa U para và ­ctimas de violencia: $500-$3.000Tarjeta de residencia por patrocinio del empleador: $1.800Visa L-1, transfer dentro de una misma empresa: $3.500 - $5.000Visa O-1, para personas con habilidades especiales: $2.500-$5.000Visa E2 para inversionistas: en torno a l os $5,000 incluyendo solamente los gastos de la visa. Con inclusià ³n de otros trmites como elaboracià ³n plan negocios la preparacià ³n del paquete completo puede rondar los $9.000. Visa de estudiante: $500-$1.500Waiver para la tarjeta de residencia por interà ©s nacional: $5.000Advance parole que se solicita independientemente de otros trmites: $350-$750El costo por representacià ³n de abogado por casos de asilo, al ser muy particulares dependiendo de las circunstancias del solicitante, pueden variar enormemente. Pero hay que esperar un costo alto, como unos $5.000 por el asilo afirmativo y $7.000 o ms por uno defensivo. Consultas gratuitas con abogados de migracià ³n Algunos abogados brindan la posibilidad de consultas gratuitas, que pueden ser de dos clases. En primer lugar, un pequeà ±o contacto con el abogado o una persona de su equipo, generalmente por telà ©fono. Se trata de ver mà ­nimamente si hay posibilidad de sacar adelante un caso migratorio. En segundo lugar, existe la modalidad de pagar por una consulta pero si posteriormente se decide contratar al abogado del monto total del trmite se descuenta la cantidad pagada por la entrevista inicial. En estos casos, aunque habrà ­a inicialmente el pago de la consulta, al final se recobrarà ­a ese dinero en la forma de descuento sobre la cantidad final a pagar.  ¿Quà © hacer si no se puede pagar abogado? Hay ciertos situaciones donde lo ms aconsejable es contar siempre con un letrado. Por ejemplo, casos en los que honestamente es mejor siempre tener un abogado al lado: citaciones en corte de inmigracià ³n.peticiones de perdones,asilo, tanto para la solicitud como para la entrevista,solicitudes de green card auto patrocinadas en casos de violencia domà ©stica (VAWA)y, en general, en todos los casos en los que hay una situacià ³n de ilegalidad y se intenta pasar a la legalidad. Si es imposible pagar el coste de un abogado, intentar que acepte el caso uno que realiza labores pro bono, es decir, acepta representar a algunos clientes sin cobrar por cuestiones humanitarias. Si no es posible, ya que generalmente tiene listas de espera grandes para estos casos en los que no cobran, intentar hablar con un representante acreditado. Y aunque es cierto que en las cortes de inmigracià ³n es posible representarse a sà ­ mismo y que el gobierno no pone abogado a aquellos acusados que no pueden costearlo, pero lo cierto es que los resultados no son positivos. Contar con un abogado que represente a un acusado en corte de inmigracià ³n no quiere decir que se vaya a ganar el caso, pero sà ­ que se va a tener una mayor oportunidad. En casos de sà ³lo llenar formularios es posible, y la ley asà ­ lo admite, llenarlos uno mismo o acudir a un consejero de inmigracià ³n, que ha de cobrar menos que un abogado. Pero hay que entender que no pueden dar consejo legal para un caso concreto ni tampoco representar en corte de inmigracià ³n, si hiciera falta. Tambià ©n se puede acudir a solicitar ayuda a organizaciones sin fin de lucro que brindan apoyo legal o para llenar documentos. Los hay muy reconocidos y no cobran nada o sà ³lo una pequeà ±a cantidad. Pero muchas veces no pueden hacerse cargo de todos los casos porque estn literalmente desbordados de trabajo. Tips que te pueden interesar Antes de contratar a un despacho es recomendable seguir ciertos consejos sobre cà ³mo  elegir abogado de inmigracià ³n  y si no se est en condiciones de hacerlo, es aconsejable contactar con alguna organizacià ³n  reputada de  defensa de los migrantes. Finalmente, los migrantes mexicanos siempre pueden solicitar informacià ³n sobre abogados y otros asuntos migratorios en el telà ©fono gratuito de la CIAM.   Este es un artà ­culo meramente informativo. No es asesorà ­a legal.