Daimlerchrysler Merger the Quest to Create “One Company” Essay Example for Free

Daimlerchrysler Merger the Quest to Create â€Å"One Company† Essay In order to understand and be critical on Daimler’s choice of partner, apart from the motives presented in the case, one also needs to consider the enterprise environment trends during the time. 90’s was a wave of mergers and acquisitions characterized by Cross-border ventures (Lipton M. , 2006). According to Lipton it was an era where size mattered and mergers were considered the one-way to internationalization and market expansion. Furthermore, nine of the ten largest deals in history all took place in the three-year period 1998-2000. Having established that, one can understand that Daimler was under market and investor pressure to go large. In such an environment, a European company would think of an integrative expansion to the vast US market as the best strategy (Japanese market too cultural different). So, from the choices of either founding a new subsidiary (high risk) or seeking for a JV, or an acquisition or a merger Daimler went for the merger. It was an effort to meet the environmental trend by increasing market share and to make a big impact to the larger competitors. Comparing the three great American car companies, GM was too large (in 1997 GM had $178b revenues compared to Daimler’s $71b) and difficult to control, Ford had investor issues (Ford family), but Chrysler, a similar size company, would seem the best partner. Chrysler was also ideal partner for Daimler because it had a good knowledge of the local market, which lowers the venture risk (Bartlett Beamish, 2011), and it would offer RD synergies and broaden the offered product range (Glavin W. F. , 2004). Considering all those factors I believe that Chrysler was the best choice of a partner. However, during those early stages of cross-cultural mergers and acquisitions there was little experience on making the venture work. In the appendix, I raise the main friction points and analyze how they should have been treated according to the literature. From this analysis we can see that the companies where different in all regards. In fact, seeing the range of daily activities and structure it is evident that the two companies operated in completely opposite. Thus, it was truly a â€Å"marriage of opposites†. But still this is not a strong argument for integration efforts failure. According to Bartlett Beamish persistence and willingness to evolve and adapt are the key to success in all collaborations. By looking through the friction points and what the literature suggests I tried to point who the person in charge of each process should in fact be. The company in Bold in appendix is the company that should lead the efforts in that process after the merger; due to its expertise which then would benefit the whole. It is evident that either Chrysler or both companies should manage the new company. In reality Chrysler tried to pass this through to Daimler but simply the management failed to penetrate the strong conservative culture of Daimler in the beginning and then it lacked the persistency. Then, Daimler took advantage of that weakness and it saw this merger not as a marriage of equals but as a takeover. So the greatest problem of the integration process was the combination of Chrysler’s inability to assert its processes and then Daimler’s failure to evolve, adapt and respect its ally. Question 2 In order to give advice I consider Bartlett’s Beamish’s framework on guidelines for a successful JV. First, there was a lack of proper pre-merger analysis which, had it been executed properly, would have raised early on the friction points. Secondly, there were no common objectives set and there was no plan on the course of action after the merger. The CIC and the PMI integration teams had no framework and dealt with issues as they arose, and thus were bound to fail. So, before embarking on a collaboration venture the CEOs should have thought of those steps. As we found, the inability to adapt and the cultural differences had been the main source of problems. Trust is the main fuel of collaboration and it can only be developed over time, being a result of shared experiences (Bartlett Beamish, 2011). In our case the two extremes merged one day and they were simply expected to run like clockwork. An alliance has similar benefits with a merger (Bartlett Beamish, 2011) but addresses the core problems better for the following reasons. A main benefit of an alliance is that when it is formed it has an exit clause, which allows the two companies to integrate more relaxed, and it offers a vehicle to learning and experimentation for the necessary bonds and trust to be formed. This lays the best conditions for a hybrid culture to form. Also, the companies’ operations that offer the greatest potential to synergies can be integrated, whereas the extreme opposite ones can be left to operate independently. This means that sectors such as RD can be jointed and Branding can operate independent. However, an alliance, alone, would not work for those companies as they wanted to go large. In my opinion, the best solution would be to form an alliance as a way to build on trust and learning and then as a second step, if both sides where mature, merge in common respect with clear objectives and structure.

McWill SCDMA Wireless Access Technology Computer Science Essay

McWill SCDMA Wireless Access Technology Computer Science Essay McWiLL is the most advanced broadband wireless solution provided by Beijing Xinwei Telecommunications Technology. The technology is based on SCDMA, and is known as Multicarrier Wireless information Local Loop (McWiLL). McWiLL combines SCDMAs traditional use in narrow-band voice and introduces a mobile broadband data service that ties into an IP-based core network. It is based on CS-OFDMA adaptive modulation, and uses dynamic channel allocation and smart antennas to enhance its throughput. SCDMA is a wireless access technology developed by Beijing Xinwei Telecom Technology Co., Ltd. The SCDMA air interface is a national wireless access standard in China. The SCDMA products contains a full suite of advanced wireless communication and networking technologies, such as smart antennas. The key technologies of SCDMA form the foundation of TD-SCDMA, an ITU Standard for 3G Wireless Communications. Earlier SCDMA products are narrowband products focusing on fixed and mobile voice applications. A new generation of SCDMA products are broadband products, Multicarrier Wireless Internet Local Loop (McWiLL), focusing on fixed and mobile voice and high speed data application. McWiLL has been deployed in several Chinese cities, including Guangzhou and Qingdao, where its been used for video, voice and data communication. McWiLL successfully served for 2008 Beijing Olympic Regatta, providing the high-definition, real-time mobile video services. Internationally it has been deployed in more than fifteen countries, such as USA, Cameroon, Nigeria, Ukraine, Malawi, and Mozambique. McWiLL is a TDD-based wireless access platform that combines SCDMA (synchronous CDMA), CS-OFDM (code spreading orthogonal frequency division multiple access), MIMO and smart antennas, as well as other wireless techniques such as adaptive modulation (up to QAM64), dynamic channel allocation and make-before-break handoff, to offer a high-speed data and voice services. All these features are designed to work with any IP core network and provide up to 15Mbps of data rate using 5MHz of spectrum. http://oksunpeng.blogspot.com/ In a way, McWiLL tries to incorporate all of todays wireless networking techniques into a single platform which is very possibly why it is almost impossible for a normal human to understand. McWiLL Base Station supports the following features: (a) Support up to 15Mbps net throughput with 5MHz bandwidth; (b) Support fixed and mobile, voice and data services; (c) Support up to 163dB link budget; (d) Support Make-before-Break handoff and L2 tunnel; (e) Support QoS and GoS features; (f) Support Over-the-Air upgrade; (g) Support low power consumption (150 Watt); (e) Support VLAN, PPPoE and penetration of private networks http://oksunpeng.blogspot.com/2009/03/what-is-mcwill.html McWill(Multi-carrier Wireless Information Local Loop) is a mobile broadband access system based on SCDMA technology platform. McWiLL Technology Smart Antennas Dynamic Channel Assignment Code Spread OFDMA (CS-OFDMA) Time Division Duplex (TDD) Efficient VoIP Technology Make-before-Break Baton Handoff Adaptive Modulation QoS GoS Security Fraud Protection McWiLL System Features Main Services ¼Ã… ¡Fixed, portable, mobile voice and data communications. Main Features ¼Ã… ¡BTS with 5MHz can support up to 15Mbps net throughput, each sector can support more than 300 simultaneous sessions, supporting high-speed mobility, handoff and roaming, N=1 frequency planning, and low latency. Product Characteristics: Support up to 100KM/H mobile speed Terminals are backward compatible Support efficient voice communications and low-bandwidth data. Support N=11 deployment. Products available in the following frequencies: 336-344MHz, 400-430MHz, 698-746MHz,1785MHz-1805MHz, 2150-2180MHz, 2525-2560MHz, 3300-3400MHz Characteristics of Chinese Rural Areas Challenges ¼Ã… ¡ Low subscriber density, large separation of villages, far away from urban areas Complicated environment (mountainous and hilly terrain) Poor facility (backhaul, power supply, etc.) Low income Current wireline/wireless communication systems cannot meet these challenges Low ARPU Less than $4/month in most areas Busty traffic High traffic especially in Chinese traditional holidays Asymmetric traffic More incoming calls than outgoing calls Little usage of value added services Unique Advantages of Deploying McWiLL Large coverage enables fewer cell sites which are expensive in developing countries, leading to much lower Capex and Opex. N=1 deployment enables a wide area network with as little as 5MHz spectrum, leading to much lower upfront investment on spectrum which is usually quite expensive. Products with a wide range of frequency allow an operator to choose the most cost effective spectrum to operate. Lower terminal cost and adequate data rates allow an operator to minimize the Opex and lower the entry barriers for a subscriber. Most McWiLL terminals can support both voice and data services. GSM/McWiLL dual mode handsets/PDAs allow an end user to enjoy 3G beyond performance of McWiLL data and cost effective voice without sacrificing easy access advantages of GSM. Summary of McWiLL Advantages Large coverage (up to 60Km) Smart antenna,400MHz frequency band Low cost Already large volume, cost effective architecture, SCDMA ASIC chipset, no royalty fees, low RD cost, low manufacture cost, multiple vendors due to SCDMA Alliance High capacity BTS capacity 24Mbps/10MHz ¼Ã…’supporting up to 8,000 voice subscribers One system fits all Via flexible configuration, one system can meet the requirements of different user groups (high-end and low-end), services (voice and data), and time (current and future). Product maturity and reliability 10 years RD, large scale deployment, redundancy architecture, long time operational networks, an experienced team of installation and customer support. Easy to install and maintenance Terminal zero install, easy-to-use tools for customer self debugging, remote access trouble shooting tools for support personnel. Abstract In this presentation, we will first give an introduction of popular wireless multiplex technologies such as WCDMA and OFDMA and then present our McWiLL technology which is an optimal integration of WCDMA and OFDMA technologies to effectively address the technical challenges of wireless broadband access, such as capacity, coverage, multipath fading, and intercell interference. In other words, McWiLL effectively avoids the major drawbacks of WCDMA and OFDMA and draws their advantages of both technologies. Unlike voice centric WCDMA or data centric OFDMA (WiMax), the McWiLL wireless broadband access system can efficiently combines both voice and data applications. Finally, we will provide brief introduction of McWiLL product roadmap and application. McWiLL Fits Chinese Rural Markets à ¢Ã¢â€š ¬Ã‚ ¢ Smart antenna and 400MHz frequency band allows the McWiLL systems to have large NLOS coverage (up to 60KM). à ¢Ã¢â€š ¬Ã‚ ¢ Multicarrier BTS can support up to 8,000 voice subscribers having sufficiently high capacity to support bursty traffic in rural applications. à ¢Ã¢â€š ¬Ã‚ ¢ Cost effective architecture and SCDMA ASICs allow the McWiLL products to have sufficiently low cost per line ($60-80 overall cost per line including both terminal and infrastructure). à ¢Ã¢â€š ¬Ã‚ ¢ Zero install of McWiLL terminals and rich tools for self and remote troubleshooting make it very easy to deploy the McWiLL systems in rural areas. à ¢Ã¢â€š ¬Ã‚ ¢ 10 years RD, redundancy architecture and large-scale deployment (>2 million subscribers) make the McWiLL products mature and reliable enough to deploy in remote rural areas. à ¢Ã¢â€š ¬Ã‚ ¢ Integrated voice and data solutions can allow the McWiLL systems to meet both current and future service requirements of rural customers. My opinion Multicarrier Wireless Internet Local Loop (McWill) is developed by Beijing Xinwei Telecom Technology Co., Ltd. It is a wireless access technology which can cover for the very large area, its coverage can up to 60KM. Therefore it is very suitable for china because it is a big country. Its been used for video, voice and data communication and successfully served for 2008 Beijing Olympic. Even though McWill is very popular but it cannot be use for every country for example, Singapore. Singapore is a small country if using the technology of McWill, there will be a lot of wasted.

Chaucers Canterbury Tales - Importance of Order in Knights Tale Essa

The Importance of Order in Knight's Tale    Chaucer claims to place the Knight's Tale just after the General Prologue by chance, the drawing of lots. The Knight draws the short straw, and all are glad for it. The appropriateness of his lengthy tale to follow is clear on some levels, and barely perceptible on others. I intend to launch my investigation of the Knight's Tale with a scrutiny of these three statements, and perhaps we shall find an interesting conclusion in this, albeit a disputable one. The honorable Host, Harry Bailey, begins this famous day of pilgrimage by calling everyone together to draw lots, "He which that hath the shorteste shal beginne." (838) He calls the Knight to draw first, presumably as a gesture of respect, as he refers to the Knight as master and lord. Harry continues to speak for a short moment, as we have the visual image of the Knight stepping up to claim his straw. The host continues to call up two more pilgrims, but quickly decides that everyone might as well draw in a free-for-all. And surprise! The Knight finds himself holding the short cut. Is it possible that Harry managed to give the Knight the short straw intentionally? "Now draweth cut," says he, "for that is myn accord" (840). A close eye may suggest some punning going on in that line: Now draw the cut (short) straw, for it is my wish. The words "cord" and "accord" were both used in Middle English, so we may be able to find some double meaning there as well. If indeed Harry wishes to giv e the Knight the "cord," there are several interesting cases to think on: a) the cord is simply the short straw, b) the cord is the hangman's rope, or c) the cord is a unit of wood cut for fuel. The hangman's rope would make for subtle sarcasm, but... ... immediate effects on the Miller, who cares not a bit for courtesy or order but only reckless lust. Hence, the Miller follows with a tale that Palamon could have appreciated, had he not known the ways of chivalry, but only those of lechery. Works Cited and Consulted Benson, Larry D., ed. The Riverside Chaucer. Boston: Houghton Mifflin, 1987. Chaucer, Geoffrey. The Canterbury Tales. The Norton Anthologyof English Literature. Seventh Edition. Two Volumes. Ed. M. H. Abrams. NewYork: Norton, 2000. Cooper, Helen. The Structure of The Canterbury Tales. Athens: U of Georgia P, 1983. Modern Critical Views: Geoffrey Chaucer, Ed. Harold Bloom. New York: Chelsea House Publishers, 1985. Spearing, A.C. Chaucer: The Knight's Tale. Cambridge: Cambridge UP, 1995. Williams, David. The Canterbury Tales, A Literary Pilgrimage. Boston: Twayne Publishers, 1987.

Animation :: essays research papers

Animation   Ã‚  Ã‚  Ã‚  Ã‚  Animation is a visual technique that creates the illusion of motion, rather than recording motion through live action. The technique is used mainly for motion pictures. Animation can be created by illustrators, filmmakers, video makers, and computer specialists. Animation is most popular in creating cartoon movies. Advertisers also employ animation to develop commercials for television. In addition, producers of instructional films may use animation to help explain a difficult idea or one that could not be shown in live action. Animation can also be combined with live action in a movie. Many animators continue to make many drawings by hand. Since the mid-1980's, however, computer assistance combined with hand-drawn animation has become standard in many movie studios. These methods created such feature-length animated films as The Lion King (1994) and The Prince of Egypt (1998).   Ã‚  Ã‚  Ã‚  Ã‚  One increasingly important type of animation is computer-generated imagery (CGI), in which the computer creates the characters and backgrounds and animates them without actually photographing either cels or figures. Films made entirely with CGI include Toy Story (1995), Antz (1998), and A Bug's Life (1998).   Ã‚  Ã‚  Ã‚  Ã‚  Most CGI-animated characters start with a sketch or small sculpture called a â€Å"maquette† that is used for reference. The artist then creates a computer image called a wireframe model. The wireframe model serves as a framework for a shell or skin that gives the computer image a solid, three-dimensional appearance. To move the character, a computer animator changes the positions of the wireframe model in a number of key frames. The computer then supplies the frames between the key frames, moving the model from one of the animator's positions to the next.   Ã‚  Ã‚  Ã‚  Ã‚  After creating the three-dimensional model, the artist adds color, texture, and shading in a process known as texture mapping. Texture mapping makes the surfaces of the characters and scenery look real. A texture map can be created by a computer program or scanned from an actual photograph.   Ã‚  Ã‚  Ã‚  Ã‚  The final step is called rendering. During rendering, the computer calculates the effect of light, color, and texture on the model's surface. For a film or video, the computer will produce a two-dimensional digital picture of the characters for each frame of the animation. The computer artist usually adjusts many visual effects, such as camera focus and transparency, during the rendering phase.

Reproductive and Therapeutic Cloning Essays -- Technology Science Gene

Reproductive and Therapeutic Cloning New areas of science often raise questions about safety. Reflecting back on the past medical technologies invented, people have always opposed it but often benefit from it later on in life. The use of in-vitro fertilization, for instance, was once a controversial issue. Some people worried that society could discriminate against humans produced as a result of IVF and humans could spread diseases. Furthermore, its usefulness cannot be predicted because it is just a research tool, and so on. Today, those worries and concerns have not manifested, but instead have brought joy and happiness to families. The people born through IVF process are as happy and equal as any other average child. It is the same with cloning technology. Upon all that we have gained from past medical technology, a majority of people have failed to see that new medical breakthrough will become as beneficial as the past ones if it is allowed to be researched. Cloning is a controversial issue because it is a new area of science and people are once again worried that, this technology will become a dangerous weapon to the society. Cloning is the creating of a genetically identical copy of an original plant or animal by using biological materials such as DNA segment (e.g. a gene or other region). According to Wilmut, The copies produced through cloning have identical genetic makeup and are known as clones. Many organisms in nature reproduce by cloning (asexually). Scientists use cloning techniques in the laboratory to create copies of cells or organisms with value traits. Their work aims to find practical applications for cloning that will produce advances in medicine, biological research, and industry.... ...ld pass a similar law and allow at least research, if not experimentation. Anxieties people have about cloning are similar to concerns about past medical technologies. This is also true about technologies in general, for instance people questioned the importance and abilities of computers, etc. Some new areas of science in the past brought up apprehensions, these technologies turned out to be beneficial to mankind. Cloning technology is now a new area of science and people are concerned about the safety and morals behind it. This system could become as stable as past medical technologies only if research is allowed. If laws are pass (with some restrictions) it could ensure that research is carried out without interfering with the principles of nature, ensures that everyone has equal access to the technology, and also used in serious cases not for pleasure.

Race Car Aerodynamics

Race Car Aerodynamics Gregor Seljak April 8, 2008 1 Introduction First racing cars were primarily designed to achieve high top speeds and the main goal was to minimize the air drag. But at high speeds, cars developed lift forces, which a? ected their stability. In order to improve their stability and handling, engineers mounted inverted wings pro? les1 generating negative lift. First such cars were Opel’s rocket powered RAK1 and RAK2 in 1928. However, in Formula, wings were not used for another 30 years. Racing in this era 1930’s to 1960’s occured on tracks where the maximum speed could be attained over signi? ant distance, so development aimed on reducing drag and potencial of downforce had not been discovered until the late 1960’s. But since then, Formula 1 has led the way in innovative methods of generating downforce within ever more restrictive regulations. Figure 1: Opel’s rocket powered RAK2, with large side wings 2 Airfoils Airfoil can be de? nead as a shape of wing, as seen in cross-section. In order to describe an airfoil, we must de? ne the following terms(Figure 2) †¢ The mean camber line is a line drawn midway between the upper and lower surfaces. †¢ The leading and trailing edge are the most forward an rearward of the mean camber line. Compared to an aircraft 1 †¢ The chord line is a line connecing leading an trailing edge. †¢ The chord length is the distance from the leading to the trailing edge, measured along the chord line. †¢ The camber is the maximum distance between mean camber line and chord line. †¢ The thickness is the distance between the upper and lower surfaces. Figure 2: Airfoil nomenclature The amount of lift L produced by the airfoil, can be expressed in term of lift coe? cient CL 1 2 (1) L = V? SCL 2 where V? denotes the freestrem velocity, ?uid density and S the airfoil area. 2. 1 Flow over an airfoilProperties of an airfoil can be measured in a wind tunnel, where constantchord wing spannes the entire test section, from one sidewall to the other. In this conditions, the ? ow sees a wing without wing tips. Such wing is called in? nite wing and streches to in? nity along the span. Because the airfoil section is identical along the wing, the properties of the airfoil and the in? nite wing are identical. Therefore the ? ow over an airfoil can be described as a 2D incompressible inviscid ? ow over an in? nite wing. Lift per unit span L? generated by an arbitrary airfoil(or any other body) moving at speed V? through the ? ud with density and circulation ? is 2 given by Kutta-Joukowsky theorem L? = V? ? . (2) Circulation around an airfoil, can be calculated with the concept of a vortex sheet, which was ? rst introduced by Prandtl an his colleagues. Consider an airfoil of arbitrary shape and thickness as shown in Figure 3. Circulation can be distributed over the whole airfoil area with surface density(vortex sheet strength) d? /ds = ? (s), where ? (s) must satisfy Kutta condition ? (trailing edge) = 0 (3) Entire circulation is then given by ?= ? (s)ds , (4) where the integral is taken around the complete surface of the airfoil.However, there is no general solution for ? (s) for an airfoil of arbitrary shape and it must be found numericaly, but analytical solutions can be found with some aproximations. Figure 3: Simulation of an arbitrary airfoil by distributing a vortex sheet over the airfoil surface. 2. 2 Thin airfoil theory Here we discuss thin airfoil in freestream of velocity V? under small angle of attack ?. Camber and thickness are small in relation with chord length c. In such case, airfoil can be described with a single vortex sheet distributed over the camber line(Figure 4). Our goal is to calculate the variation of ? s), such that the chamber line becomes streamline and Kutta condition at trailing edge, ? (c) = 0, is satis? ed. 3 Figure 4: Thin airfoil approximation. Vortex sheet is distributed over the chamber line The velocity at any point in the ? ow is the sum of the uniform freestream velocity and velocity induced by the vortex sheet . In order the camber line to be a streamline, the component of velocity normal to the camber line must be zero at any point along the camber line. w ? (s) + V? ,n = 0 , (5) where w ? (s) is the component of velocity normal to the chamber line induced by the vortex sheet and V? n the component of the freestrem velocity normal to the camber line. Considering small angle of atack and de? ning ? (x) = dz/dx as the slope of the chamber line, V? ,n can be written as (Figure 5) V? ,n = V? ? ? dz dx (6) Because airfoil is very thin, we can make the approximation w ? (s) ? w (x) , (7) where w (x) denotes the component of velocity normal to the chord line and can be, using the Biot-Savart law, expressed as c w (x) = ? 0 ? (? )d? 2 ? (x ? ? ) (8) Substituting equations (6), (7) and (8) into (5) and considering Kutta condition, we obtain 1 2? c 0 ? (? )d? dz = V? ? ? x dx ? (c) = 0 undamental equations of thin airfoil theory. 4 (9) Figure 5: Determination of the component of freestrem velocity normal to the chamber line In order to satisfy this conditions , we ? rst transform our variables x and ? into c c x = (1 ? cos ? 0 ) (10) ? = (1 ? cos ? ) 2 2 and equation (9) becomes 1 2? ? 0 ? (? ) sin ? d? dz = V? ? ? cos ? ? cos ? 0 dx (11) with a solution that satis? es Kutta condition ? (? ) = 0 ? (? ) = 2V? A0 ? 1 + cos ? An sin(n? ) + sin ? n=1 (12) In order to ? nd coe? cients A0 and An , we substitute equation (12) into equation (11) and use the following trigonometric relations ? 0 sin(n? ) sin ? ? = cos(n? 0 ) cos ? ? cos ? 0 (13) ? sin(n? 0 ) cos(n? )d? = cos ? ? cos ? 0 sin ? 0 (14) ? 0 and ? nnaly obtain ? dz An cos(n? 0 ) = (? ? A0 ) + dx n=1 5 (15) This equation is in form of a Fourier cosine series expansion for the function dz/dx. Comparing it to the general form for the Fourier cosine expansion we obtain 1 ? dz A0 = ? ? d? 0 (16) ? 0 dx 2 ? dz cos(n? 0 )d? 0 (17) An = ? 0 dx The total circulation due to entire vortex sheet from leading to the trailing edge is c cc ? (? ) sin ? d? (18) ? (? )d? = ?= 20 0 Substituting equation (12) for ? (? ) into equation (18) and carrying out the integration, we obtain ? = cV? ? A0 + A1 (19) 2 hence the lift per unit span, given by Kutta-Joukowski is 2 L? = V? ? = c V? ? A0 + ? A1 2 (20) This equation leads to to the lift coe? cient in form cl = ? (2A0 + A1 ) = 2? ? + 1 ? ? 0 dz (cos(n? 0 ) ? 1)d? 0 dx (21) and lift slope dcL = 2? (22) d? Last two results are important. We can see, that lift coe? cient is function of the shape of the pro? le dz/dx and angle of attack ? , and that even symmetrical wing produces lift, when set under an angle of attack. Lift slope is constant, independently of the shape of the pro? le, while the zero lift angle lS ? ?L=0 = ? 1 ? 0 dz (cos(n? 0 ) ? 1)d? 0 dx (23) depends on the shape. The more highly chambered the airfoil, the larger is ? L=0 2. 3 Vi scid ? ow By now, we have studied the inviscid incompressible ? ow. But in real case, ? ow is viscous. It is time to compare our theoretical results with real one. In Figure 6, we can see variation of lift coe? cient with the angle of attack. 6 At low angles of attack cl varies linearly with ? , as predicted by the theory. However, at certain angle of attack, cl reaches it’s maximum value cl,max and starts to decrease. This is due to viscous e? ect of the ? uid (air). First, the ? w moves smoothly over the airfoil and is attached over most of the surface, but at certain value of ? seperates from the top surface, creating a wake of turbulent ? ow behind the airfoil, which results in drop in lift and increase in drag. Figure 6: Variation of lift coe? cient with the angle of atack. To increase lift of the airfoil, we must increase cl,max . As we have seen, the cl,max of the airfoil primarily depends on it’s shape. Airfoil’s shape can be changed with use of multiele ment ? aps at the trailing edge and slats at leading edge. They increase chamber of the airfoil and therefore its cl,max .The streamline pattern for the ? ow over such airfoil can be seen in Figure 7. 3 Finite wings Properies of airfoils are the same as the properties of a wing of in? nite span. However, all real wing are of ? nite span and the ? ow over ? nite wing is 3 dimensional. Because of higher pressure on the bottom surface of the wing, the ? ow tends to leak around the wing tips. This ? ow establishes a circulary motion that trails downstream of the wing. A trailing vortex is created at each wing tip. These wing-tip vortices induce a small downward component of air velocity, called downwash . It produces a local relative wind which is Figure 7: Flow over multielement airfoil. directed downward in the vicinity of the wing, which reduces the angle of attack that each section of the wing e? ectively sees ?ef f = ? ? ? i (24) and it creates a component of drag, de? ned as induc ed drag. 3. 1 Prandtl’s classical lifting-line theory The idea of lifting line theory, is to use two dimensional results, and correct them for the in? uence of the trailing vortex wake and its downwash. Let’s replace a ? nite wing of span b, with a bound vortex 2 extending from y = ? b/2 to y = b/2. But due to the Helmholtz’s theorem, a vortex ? ament can’t end in a ? uid. Therefore assume the vortex ? lament continues as two free vortices trailing downstream from the wing tips to in? nity(Figure 8). This vortex is due to it’s shape called horseshoe vortex. Downwash induced by such vortex, does not realistically simulate that of a ? nite wing, as it aproaches at wing tips. Instead of representing the wing by a single horseshoe vortex, Prandtl superimposed an in? nite number of horseshoe vortices, each with an in? nitesimally small strength d? , and with all the bound vortices coincident along a single line, called the lifting line.In this model, w e have a continious distribution of circulation ? (y ) along the lifting line with the value ? 0 at the origin. The two trailing vortices in single horseshoe vortex model, have now 2 A vortex bound to a ? xed location in ? ow 8 Figure 8: Replacement of the ? nite wing with single horseshoe vortex. Figure 9: Superposition of an in? nite number of horseshoe vortices along the lifting line. became a continious vortex sheet trailing downstream of the lifting line,and the total downstream velocity w , induced at the coordinate y0 by the entire trailing vortex sheet can be expressed as w (y 0 ) = ? 4? b/2 ?b/2 (d? /dy )dy y0 ? y (25) The induced angle of attack at the arbitrary spanwise location y0 is given by ? i (y0 ) = arctan ?w (y0 ) ?w (y0 ) = , V? V? (26) where we considered V? ? w (y0) and arctan(? ) ? ? for small values of ?. Now we can obtain an expression for the induced angle of attack in term of the circulation distribution along the wing ?i (y0) = ? 1 4? V? 9 b/2 ?b/2 (d? /dy )dy y0 ? y (27) Combining results cl = 2? (y0) V? (28) and cl = 2? [? ef f (y0 ) ? ?L=0 ] (29) for coe? cient of lift per unit span from thin airfoil theory, we obtain ? ef f = ?(y0 ) + ? L=0 ?V? c(y0 ) (30)Substituting equations (27) and (30) into (24), we ? nally obtain the fundamental equation of Prandtl’s lifting line theory. ? (y 0 ) = 1 ?(y0 ) + ? L=0 (y0 ) + ?V? c(y0 ) 4? V? b/2 ?b/2 (d? /dy )dy y0 ? y (31) Just as in thin airfoil theory, this integral equation can be solved by assuming a Fourier series representation for the distribution of vorticity N An sin n? ?(? ) = 2bV? (32) n=1 where we considered transormation y = (? b/2) cos ? , with 0 ? ? ? ? and coe? cients An must satisfy Equation (31). With such vorticity distribution, Equation (31) becomes ?(? 0 ) = N N 2b sin n? 0 nAn An sin n? 0 + ?L=0 (? 0 ) + ?c(? 0 ) n=1 sin ? 0 n=1 (33) The total lift distribution is obtained by integrating equation for lift distribution over the span L= b/2 ?b/2 V? ?(y )dy (34) C oe? cients of lift and induced drag3 , can be calculated via equations CL = and CD = 2 L = q? S V? S D 2 = q? S V? S 3 b/2 ?(y )dy (35) ?i (y )? (y )dy (36) ?b/2 b/2 ?b/2 Note the di? erence in nomenclature. For 2D bodies, coe? cients have been denoted with lowercase letters. In 3D case, we use capital letters 10 respecteviliy. Considering expressions (32) and (33), they can be written as CL = A1 ? AR (37) and 2 CL (1 + ? ) (38) ?AR here AR is aspect ratio of ? nite ? ng, de? ned as AR = b2 /S , and ? = N 2 2 (An /A ? 1) . Note that CL depends only on the leading coe? cient in Fourier series expansion and that ? ? 0. Therefore, the lowest induced drag will be produced by a wing where ? = 0, that is, n = 1. Such circulation distribution is given by ? (? ) = 2bV? A1 sin ? and is known as elliptical circulation distribution CD,i = 4 Ground e? ect The main di? erece between wing application in aviation and car racing is, that cars are in contact with the ground. Therefore, wing experien ces some additional e? ects due to ground proximity.Remember the wing tip vortices we mentioned at the beginning of the previous section. They do nothing but harm, as they increase drag and decrease lift at given angle of attack. When ?ying near to the ground, the ground partially blocks(Figure 10) the trailing vortices and decreases the amount of downwash generated by the wing. This reduction in downwash increases the e? ective angle of attack of the wing so that it creates more lift and less drag than it would otherwise. This e? ect is greater, the closer to the ground the wing operates. Figure 10: E? ect of the ground proximity on creation of the trailing vortices.Another way to create downforce is to create low pressure area underneath the car, so that the higher pressure above the car will apply a downward force. The area between car’s underbody and the ground, can be thougth as an example of Venturi nozzle. The Venturi e? ect may be derived from 11 a combination of Bern oulli’s principle and the equation of continuity. The ? uid velocity increases through the constriction to satisfy the equation of continuity, while it’s pressure decreases due to conservation of energy. The gain in kinetic energy is supplied by a drop in pressure.The main advantage of ground e? ect is, that it produces almost no drag. 5 Applications in car racing Now summarize what we have learned so far. The coe? cient of lift increases with increasing angle of attack. At some angle, ? ow seperates from the wing, which causes drop of lift coe? cient. With use of multidimensional ? aps, we increase chamber of the airfoil and thus maximum coe? cent of lift. In 3 dimensional case, vortices appear at wing tips. They reduce wing’s e? ciency and increase drag. The lowest drag can be achieved with elliptically shaped wing. Dimensions of the wing are also important.Wing with greater surface, produces more lift and wing with higher aspect ratio induces less air resista nce. In the next sections, we will see, how engineers used this principles at developing the main aerodynamical parts of racing cars. 5. 1 Rear wing First rear wing appeared in 1966, when Jim Hall equiped his Chaparral 2E with a rear wing. From then on, use of wings grew quickly. First wings were mounted high over the rear end of the car to operate in indisturbed ? ow. They were also mounted on pivots, so the driver was able to change the angle of attack during the ride. High mounted wings often broke o? uring the race and were therefore prohibited by FIA. In Formula 1, wings were ? rst introduced in 1968 at the Belgium grand prix, when Ferrari used full inverted rear wings, and Brabham did likewise, just one day after the Ferrari’s wings ? rst appeared. Modern rear wings produce approximately 30-35 % of the total downforce of the car. A typical con? guration(Figure) consists of two sets of airfoils connected to each other by the wing endplates. The most downforce is provided by the upper airfoil. To achieve the greatest possible lift coe? cient, it consists of multiple high aspect ratio elements, which prevent ? w separation. Angle of attack depends on circuit con? guration. On tracks with many turns, more downforce is needed, therefore the wing is set at higher angle of attack. Conversely, on tracks with long straights, wing has small angle attack, thus reducing air drag and allowing higher top speeds. Lower airfoil section ac12 Figure 11: Chapparal 2E (left) and Ferrari 312 (right). tually reduces the downforce produced by total rear wing, but it creates a low-pressure region just below the wing to help the di? user4 to create more downforce below the car. Ususally it consists of two elements.Another important part of rear wing are endplates . They provide a convenient way of mounting wings, but also have aerodynamic function. They reduce the 3D e? ect of the wing by preventing air leakage around the wing tips and thus formation of trailing vortices. An additional goal of the rear endplates is to help reduce the in? uence of up? ow from the rear wheels. The U-shaped cutout from the endplate further alleviates the development of trailing vortices. 5. 2 Front wing The front wing on the car produces about 1/3 of the car’s downforce and it has experienced more modi? ations than rear wing. It is the ? rst part of the car to meet the air mass, therefore, besides creating downforce, it’s main task is to e? ciently guide the air towards the body and rear of the car, as the turbulent ? ow impacts the e? ciency of the rear wing. Front wings appeared in Formula 1 just two weaks after the ? rst rear wings, on Lotus 49B. First front wings were quite simple with single rectangular airfoil with ? at vertical endplates to reduce wing tip vortices. First improvement appeared in 1971, with so-called Gurney ? ap. This is a ? at trailing edge ? p perpendicular to the chord and projects about 2% of the chord. It can improve the perfor mance of a simple airfoil to nearly the same level as a complex design. The same year, the concept of elliptical wing was applied. March equiped it’s 711 with elliptical front wing. Two years later Ferrari avoided wing-body interaction with wing mounted quite far ahead 4 See section 5. 3 13 Figure 12: Modern rear wing consists of upper(2) an lower(3) airfoil section mounted on endplates (1) with U-shaped cutout (4). from the body. Multi element wings were introduced in 1984 by McLaren.The angle of attack of the second element was allowed to be modi? ed so that the load applied on the front wing could be changed to balance the car according to the driver’s wishes. In 1990 Tyrell raised the nose of it’s 019 to increase the ? ow under the nose cone and improve ? ow conditions under the car. This concept avoids wing-body interaction and allows the front wing to operate in undisturbed ? ow. It also enlarges e? ective area of the wing. After Imola 1994, the FIA regula tions do not allow any chassis parts under a minimum ground height. This clearance is di? erent between the centre and the side of the car.Teams used this to curve front wing in the centre of the span and regain some of the lost ground e? ect. In 1998, regulations decreased the width of Formula 1 car, so the front wings overlapped the front wheels. This created unnecessary turbulence in front of the wheels and reducing aerodynamic e? ciency of the wing. With reducing wing’s span this could be avoided, but it would also decrease wing’s aspect ratio. Insted this, teams use wing tips to direct the air around the wheels. 14 Figure 13: Con? guration of modern front wing. Two element airfoil (1 & 2) is mounted under the nose of the car (5).Endplates (4) direct air around the wheels and curved area (4) under the nose increases wing’s e? ciency. 5. 3 Ground e? ect The second revolution in Formula 1 aerodynamics occurred about a decade after the ? rst, with the introucti on of the Lotus T78 in 1977. Lotus T78 and it’s further development, Lotus T79, were ? rst cars to use ground e? ect. The underbody took shape of inverted wing pro? le(Figure). The decreasing crosssectional area accelerated the air? ow and created low pressure underneath the car. The gap between the bottom of the sidepods and the ground was sealed with so-called sidepods. They helped to maintain 2D ? w characteristics that provide increased downforce and reduced drag, compared to a typical 3D wing. Skirts enabled very high cornering speeds and were prohibited by the rules, due to safety reasons and from 1983 onwards, the tehnical regulations in Formula 1 require the underbody panel between the wheels to be completely level. The ? ow wolume between the vehicle and the ground is strongly dependent on the car’s attitude relative to the ground. This correlation is illusrtated in Figure. Very small ground clearence results in positive lift, since there is almost no air? ow between the underbody and the ground. With in- 15Figure 14: Some historical milestones in front wing develpment. Lotus 49B, March 711, Ferrari 312 T2 and Tyrrell 019. Figure 15: Lotus T79 and sketch of it’s underbody creasing ground clearence the air? ow produces low pressures causing overall lift to be lowered to negative values and then to rise again as ground clearence continues to increase. This is due to the fact that the ? ow velocity under the car decreases as ground clearence increases. More downforce can be generated using a di? usor between the wheels at the rear of the car. The air enters the di? user in a low-pressure, high-velocity state after accelerating under the 16 ar. By gradually increasing the cross-sectional area of the di? user, the air gradually slows down and returns to its original free-stream speed and pressure. The di? user’s aim is to decelerate the air without it separating from the tunnel walls, which would cause a stall, reducing the down force and inducing a large drag force. By installing an inverted wing close to the di? user exit 5 it is possible to create a low-pressure area, which essentially sucks the air from the di? user. The di? user and wing combination permits a higher air mass ? ow rate through the di? user, thus resulting in higher downforce.Sharp edges on the vertical tunnel walls generate vortices from entrained air and help con? ne the air through the di? user and reduce the chance it will separate. Figure 16: Correlation between lift coe? cient and ground clearence(left) and di? user on Ferrari F430(right) Again Chaparral, showed completely new way to create downforce. The Chaparral 2J in 1969 used two rear fans to suck in air from under the car, thus creating low pressure under the car. Big advantage of this concept is, that downforce can be generated independently of the speed. Fans were also used in Formula 1. Brabham BT46 used a rear mounted fan driven o? he gearbox. It won it’s debut rac e in 1978, but was promptly banned by the governing body. Barge boards were ? rst seen in 1993 and their purpose is to smooth the air? ow around the car and into the radiator intakes. They are most commonly mounted between the front wheels and the sidepods (See Figure) . Their main purpose is to direct relatively clean air into the sidepods. Clean air is from the low section of the front wing where air? ow is fairly una? ected 5 See rear wing section 17 Figure 17: Two cars which used fans to create downforce. The Chaparral 2J â€Å"sucker car† (left) and Brabham BT46 â€Å"fan car† y the wing and far away from tires, which may throw stones and debris in to the radiator. Bargeboards also produce vortices, to seal the area between the sidepots and the surface. They work as a substitude for skirts. Figure 18: Bargeboards on McLaren MP4/8 6 Conclusion References [1] J. D. Anderson; Fundamentals of Aerodynamics 18 [2] Applied Aerodynamics: A Digital Textbook, http://www. de sktopaero. com/appliedaero/preface/welcome. html [3] W-H Hucho: Aerodynamics of Road Vehicles [4] Peter Wright: Formula 1 Technology [5] Milliken,Milliken: Race Car Vehicle Dynamics [6] F. Mortel: Cran? eld Team F1: The Front Wing 19

How structural and linguistic devices are used to target specific audiences in printed media texts Essay

Different audiences expect and react to different ideas, presentational devices, linguistic devices and so on. For example teenagers may expect bright, vibrant colours and exciting design, whereas older people may look for softer, neutral colours and a more formal design. Of course, these are stereotypical views but the designers of the media texts must make them with a stereotypical view of their audience in mind. In this essay I will look at three different media texts aimed at different groups and explain how they attempt to appeal to these audiences. Firstly I will compare the ideas put forward in the three texts. In the Club 18-30 leaflet the focus is mainly on going out and having fun, in clubs, pubs and on beaches. The Superfamily piece talks about the activities that a family can participate in, such as pool games, quizzes, tennis courts, squash courts and fantasy golf. It also tells the audience about the things done to make a family holiday easier, such as baby care, children’s clubs and so on. The Forever Young brochure focuses on the older generation ands talks about the activities and facilities that they might enjoy, such as tennis, aerobics and golf, cathedrals to visit and conveniences like laundry services, money exchange, spacious bar and sun terraces. Now I will look at the presentational and structural devices in the three texts. In the Club 18-30 text bright, vibrant colours are used such as pink, blue, yellow and red. The title states the target audience straight away making it very obviously eye-catching to the right people. The pictures used are those of people dancing in a club and having fun as this is what most people going on this holiday want to do. This is not a full page advertisement as there is only a very small amount of information wanted; about the clubs, bars, beaches etc. This is all given in a fun, jaunty font with not too much reading needed. The Superfamily brochure is done in red, white and pale yellow. These are soft, welcoming, almost primary colours. This emphasises that this is a family advertisement. There are pictures a families by the pool as well as kids playing and having fun. All the borders are wavy and curved making this feel like a safe place for children and the font is plain. The Forever Young brochure has soft, autumn colours as well as natural blues and greens. Also, the pictures are serene. This is because the average older person wants a calm relaxing holiday. There is a full page layout with plain, simple borders. There are pictures of a cathedral and an empty pool. This helps add to the feeling of calm and relaxing on the holiday. I will next look at the language used in each of the pieces. In the Club 18-30 piece the language used is ‘cool’ and ‘slang’ with misspelled words such as ‘in yer face’. This is to target the younger audience. It is humorous yet with some facts, such as bars, clubs and beaches to visit. There are some opinions such as ‘home to some of Europe’s premier DJs’. It states what the younger audience may worry about when it says that ‘you’ll need a fair bit of wedge’. It also states that there are many things to do ‘on your doorstep’ suggesting great ease, an important factor to youth. The Superfamily brochure uses informal yet informative language, like ‘for the sporty among you’. It is persuasive and serious, giving the reader a lot of reasons why the holiday is right for them. However in doing this it keeps a very friendly and approachable attitude as it wants to appeal to families. It states the many things that they will do to make family life easier, such as baby care and children’s clubs. Forever Young uses formal language as this is what appeals to a lot of the older generation. It is serious and informative, stating plainly what things there are to do and makes them seem calm for example ‘it has a traditional, relaxed feel about it’. This is important as most older people want a relaxing holiday. It is persuasive as it uses opinions about things like ‘prettiest’ and ‘traditional’. Overall I believe it is very important for advertisers to use all means at their disposal to attract the target audience. They must choose the right presentational devices, the right language and the right style in order to convince the target audience to buy their product.