Speaker Driver: Comparison of Options

Speaker Driver: Comparison of Options Speaker driver choice is a very important consideration, since the transducers themselves are of course the most fundamental part of the speaker. Regardless of other factors, one can never expect inferior drivers (and hence the system as a whole) to perform well. There are two main options when choosing drivers; electrostatic or conventional voice-coil designs. Although many seem under the impression that electrostatic loudspeakers are a modern invention this is not the case; Janszen was granted the first U.S. patent for such a device in 1953[1]. Considering the relatively small market penetration of electrostatic transducers and the fact that they tend to appear largely in high-end designs, one might be led to assume that electrostatic panels are superior to conventional drivers. This however is only partially true. One advantage of electrostatic panels is that full-range designs are possible, eliminating the need for crossovers and hence the associated problems with frequency and phase response in the crossover band. Another advantage is that the electrostatic panel is generally very light and hence offers excellent transient response, whilst also offering very good directionality and imaging. The latter may also be seen as disadvantage, since it effectively makes the ideal listening position rather narrow. In terms of disadvantages, the chief problem with electrostatic designs is a difficulty in reproducing bass frequencies at high SPLs. Generally the panel excursion is small, which makes it hard for electrostatic transducers to move the required volume of air at low frequencies. Furthermore, since electrostatic transducers are not meant for use with an enclosure, phase cancellation is an issue, again resulting in reduced bass performance. Audiostatic, a company that manufactures audiophile full-range electrostatic speakers, admit of their own devices with regard to bass that â€Å"Obviously because of the limited membrane excursion they wont produce ear shattering levels at that frequency†[2]. As a result of the aforementioned bass performance, many high-end electrostatic speakers are in fact hybrids, using voice-coil woofers for low frequencies with electrostatic panels covering the mid and high range. One example is the Martin Logan Summit[3], which whilst described as â€Å"our most advanced and sophisticated full-range loudspeaker† nevertheless makes use of two 10† woofers for low-end reproduction. Of course in this situation a crossover is still required, so the advantage of the possibility of a full-range design is often nullified in practice. Still, electrostatics may prove very attractive as high quality mid to high frequency drivers, although they are certainly not cheap. In choosing conventional voice-coil drivers, there are many factors to consider. In terms of quality, it is certainly true that one does indeed get what one pays for. Whilst high quality manufacturers such as SEAS[4] are happy to provide detailed frequency response plots and Thiele-Small parameters for their transducers, many cheaper manufacturers are less transparent about their devices. One common trick to beware of, often used by less scrupulous manufacturers, is the quoting of a recommended frequency range without stating the variation in output (in dB) across this range. A recommended operating range without any indication of the actual performance within the frequency band is virtually meaningless. Many assume a  ±3dB range is implied when reading such data; it is unwise to make such assumptions. Furthermore, even if frequency response across a range is qualified with the variation in output in dB, this is still not ideal. Obviously one desires that any variation in output magnitude will be a smooth variation; one still has no idea of how â€Å"lumpy† the response might be. For these reasons it is best to choose drivers that are accompanied by frequency plots, since this gives a far more accurate representation of true performance. Another important consideration in choosing a driver is the application for which it is intended. For example, a woofer with a high maximum cone excursion and low Fs may perform very well in a large sealed cabinet but be totally unsuited to a ported implementation (Dickason, 2000). One can make use of the quoted Thiele-Small parameters to ascertain whether the driver is suitable for its intended purpose. Construction materials also give an indication of how the driver may sound. In terms of woofer and midrange drivers, for example, an aluminium cone may indicate greater bass precision than an otherwise equivalent transducer with a paper cone; softer cones are associated with greater distortion than their stiffer counterparts. However, as Larsen (2003) notes â€Å"cone break-up behaviour and frequency response was shown to be strongly dependant on the Geometrical Stiffness of the Cone†. Hence the geometry of the design may be more important than the material used. Diameter of the driver is also a hugely important factor for woofers, although of minor importance for tweeters. To reproduce bass frequencies at good SPLs, a large volume of air must be moved by the driver. To this end, there is absolutely no way a 6† driver can compete with a 12† driver of similar quality in terms of bass extension; it is simply not physically possible. Power handling is another consideration that must be given thought when choosing a driver; the peak short-term power dissipated by a transducer can easily be double its long-term rating. Naturally for the best performance it is desirable to ensure that the driver is not operating too close to its quoted limits. One should think carefully about how hard the driver is likely to be driven and ensure its power handling is adequate; overdriving a unit at best will result in distortion and at worst may cause irreversible damage. In many cases users overdrive and damage units in an attempt to achieve a higher SPL, particularly in the bass region. If the system requirements are adequately specified and designed for, this should not happen. For the high-budget client, the best solution will either be high-quality voice-coil drivers carefully selected to complement each other, or a hybrid electrostatic implementation. It is difficult to recommend a fully electrostatic solution due to the associated problems with low frequency performance, although for some clients this may be acceptable. For the low-budget client, standard voice-coil drivers are the only solution. The quality of the drivers used will largely be influenced by pricing; one should carefully consider all factors and attempt to find the best solution within budget. Datasheets should be closely scrutinised to identify the strengths and weaknesses of each option before a solution is chosen. In conclusion, notwithstanding the electrostatic debate, driver choice is largely influenced by price and performance. In general, the better specified the driver, the more expensive it is likely to be. If working with a high budget, one is likely to simply choose the best specified drivers. Conversely, with a limited amount of capital, one must make the best compromise that can be reached within budget. Sources Larsen, Peter. (2003). Geometrical Stiffness of Loudspeaker Cones, Loudsoft. Borwick, John. (2001). Loudspeaker and Headphone Handbook, Focal Press. Dickason, V. (1995). The Loudspeaker Design Cookbook, Audio Amateur Publications. Rossing, T. (1990). The Science of Sound, Addison-Wesley. 1 Footnotes [1] United States Patent 2,631,196 [2] http://www.audiostatic.com/faq.html [3] http://www.uk.martinlogan.com/speaker_intro/summit.html [4] http://www.seas.no Effect of Globalisation on Culture: Annotated Bibliography Effect of Globalisation on Culture: Annotated Bibliography John Tomlinson Globalization and Culture John Tomlinson analyses the globalization and the culture relationship, Globalization is in the center of modern culture; cultural practices are in the globalization center.  In John Tomlinson view, globalization and culture could be interpreted as relationship that they complement each other. John Tomlinson thinks that researching Globalization from the fields of political science, economics, sociology and communication to lead the field of culture, cultural practices are designed to reveal the meaning of globalization On globalization, John Tomlinson thinks the point of view from the daily life experience and to analyze the sense of intimacy, uniqueness.  On culture, John Tomlinson reflect on the cultural and political and economic relationship between the practice to clarify the complex cultural purposes, that is what makes life full of meaningful experience. John Tomlinson focused on the Deterritorialization of the concept that deterritorialization of our current globalization and cultural conditions, it exists in everyday experience among the grasp of many aspects of cultural globalization. Globalization fundamentally is the place we live, it makes our cultural practices, cultural identity and cultural experience and the relationship between the occurrences of the transition, it reduces or removes the daily dynamic between cultural and territorial positioning Contact; This culture, the opportunities and pitfalls. So, John Tomlinson called for world unity. Hardt, Michael; Negri, Antonio, (2000) Extract from Hardt, Michael; Negri, Antonio, Empire pp.xi-xvi,3-21, Cambridge, Mass.: Harvard University Press Hardt, Michael; Negri, Antonio, hardt criticize the globalization, their bookempire could be considered as the representative of the anti-globalization works. They argue that the globalization is the capitalist production and economic relations have become more autonomous from political controls ,But with the traditional left to some of the different anti-globalization, this book address the global changes in an attempt to put forward in the context of globalization, new practice ideas. Hardt, Michael; Negri, Antonio books argument can be roughly simplified as follows: Globalization has led to changes in capitalism, the nation-state boundaries disappear, the new Empire has been formed, showing a new form of sovereignty, is composed of many countries and a joint supranational organizations  . Empire does not establish a power center, nor rely on fixed boundaries or barriers. Empire is a decentralized to the regions with the tools of the rule, and gradually  areas into the global expansion of its open and whole. Such an abstract rather than concrete empire how to rule? Finally, Hardt, Michael; Negri, Antonio called the masses are a utopian construct. Sociology of knowledge that, in the absence of any organized sports, leadership, and the dominant ideology, even if there is no amount of suffering, it will only submit to humiliation.  The authors argue that the masses is the seed of the revolution, they need international links to change the empire, but these people in todays nation-states under the barrier, how could the international links, how to overcome language differences Saskia Sassen (2008), Neither global nor national: novel assemblages of territory,  Authority and rights Columbia University, USA,  Ethics Global Politics, Vol. 1, No. 1 2, 2008, pp. 61 79 Saskia Sassen is the Professor of Sociology, Columbia Universityà ¯Ã‚ ¼Ã…’the globalization leads the Unequal distribution of material resources, cultural colonialism and the depletion of non-renewable raw materials, the source of political conflict between North and South. Consequences of this phenomenon, such as global climate change to all social classes and the widening between the poor countries  gap between the rich have led to greater social crisis. Sassen thinks that the world only about 40 nodes in a transnational influence in the city, most of them located in the North Atlantic global subsystem; Globalization and World Cities Study Group believes that the world only 50 World City  , and another 60 to 70 cities to show the world the city part of the evidence Saskia Sassen states that Economic globalization not look at the globalization of capital accumulation, but also the production process of globalization.  If the economic globalization, the globalization of the production process as we see more than just capital, capital is only one aspect of economic globalization, it is another aspect of the globalization of labor, especially in the international movement of labor.  In the process of economic globalization, the cities, especially global cities, a place of convergence of capital and labor, the coordination center of the world economy, and thus become the problem of inequality in the globalization process of strategic intervention  place.  Specifically, how interventions, A Brief History of Neoliberalism, David Harvey, Oxford University Press David Harvey Examine the new liberalism in the past few decades to stir up trouble, and largely reshaped the pattern of international politics, not only for our understanding of the financial crisis, but also for understanding the development of global capitalism. With the new round of financial crisis sweeping the world and impact on all walks of life, people have tried from all aspects, directly or indirectly, to discuss the origin and development of the crisis, including the re-study of world history over the past few decades in the political  and economic theory and practice.  In this context, there is a scholar claim that the capitalist world have long been in crisis for a long time.  People who make this assertion is David â‚ ¬Ã‚ ¢ Harvey At the beginning, David Harvey analyze the U.S. war in Iraq, the United States in the implementation of the new Chilean liberal reform, pointed out that neo-liberal reforms, but at outside the United States once again in the experiment, then it could be the sample as their internal reform Of course, we should not forget the teachings of Marx In the past philosophers only interpret the world, but the important thing is to change the world. For understanding the status of our world today and the new liberalism of the context, although this small book may be many areas for improvement, but still occupies an important position. Arjun Appadurai, Disjuncture and Difference in the Global Cultural Economy, 1990 7: 295 Theory Culture Society, DOI: 10.1177/026327690007002017. Arjun Appadurai thinks that disjuncture and difference are normally in the global cultural economy, today, the central issue is the tense relationship between global interaction heterogeneity and cultural homogeneity. Homogenization is globalization and the universal, heterogeneous, that the pursuit of ethnic, indigenous rights and the maintenance of cultural identity.  As mentioned earlier, the key is, homogeneity of the substance at the expense of heterogeneity as the price, The basic efforts are to discuss the disadvantaged and marginalized groups in the cultural status quo from the inequality freed.  From an academic perspective, the demands of cultural heterogeneity consist of the following reasons: First, the cultural standpoint, it has a position of cultural relativism.  The need for different cultures to maintain their autonomy, because whether it is strong or weak culture, are equal in rights, no one culture is superior to other cultures, nature.  Therefore, there is no one culture can be for other cultural legislation, and its own advantages and disadvantages of other cultures for the evaluation criteria.   Thus in Arjun Appadurai thinks that which derived from the resistance of a strong culture means that it is not for the emphasis on their own than any other culture their own special appeal, but in Europe or the male-centered center of power has become a universal rule in the context of intercultural  the pursuit of equal status. Ulrich Beck, the Terrorist Threat: World Risk Society Revisited, 2002 19: 39 Theory Culture Society, DOI: 10.1177/0263276402019004003 the British sociologist Ulrich Beck, with his point of view, representation of contemporary social structures and life patterns generated by the many changes in availability of a second modern the character, and different from the traditional modern / post-modern painting points.   In this book, the second modern and cosmopolitanism, points out the first modern over-development, will turn off the collapse of global market and the nation-state patterns, and will generate reflection type of cultural development.  Cultural development in the reflection type, the modern rational and the Universe would have been a powerful challenge of all; society will also be the inner self to begin conversion.  Peoples cultural experience and experience in space, including the cultivation of various degree of recognition, diversity of life forms of the cross, the Political Action Without Borders, etc., will have a more diversified development. Risk society has the global common foundation, because in the second modernity, whether political, economic or ecological crisis, the risk of the spread is no national boundaries; so modern risk society, must put in the context of globalization down interpretation.  However, Baker on the second modern in the description of the world, the globalization of the past simply is not the same.  In order to interpret more in line with the concept of global development community, and puts forward a cosmopolitan, containing the words all men are brothers, David held Anthony McGrew, David Goldblatt Jonathan Perraton, Global Transformation Early in the 20th century, David held and the famous sociologist Anthony Giddens, Professor, who put together the relevant risk society of the concepts and theories Ecological, financial, military, terrorists, biochemical and information, and other risks in our contemporary world in a way there is overwhelming.  To the risk we experience everywhere; we could only make the following three types of reaction: denial, indifference and transformation.  The first approach is largely rooted in modern culture, but it ignored this attitude has denied that the political risks; second approach succumb to the kind of postmodern nihilism which type of argument;  The third approach led to my theory of world risk society issues raised: the future of man and the diversity of the expected consequences with the risk of changes in how the impact and awareness of modern society, survival  conditions and the system? Global default is a rational increase in demand uncertainty.  Caused by industrial society because of the uncertainty does not necessarily lead to confusion or disaster.  Rather, the uncertainty can not be calculated can also a source of creativity, which is a contingency to allow reason and experiment new things.  Thus, the current end of a pervasive sense of the kind of odds Mike Featherstone, Global Culture: Nationalism, Globalization, and Modernity Mike Featherstone is currently Britains consumer culture theorists.  In this book, consumer culture, as his object of study, reviews the theory of consumer culture Featherstone three main aspects: first by an aesthetic theory of everyday life, this is the theory of consumer culture Featherstone core and foundation.  While the previous practice of daily life and consumption has some research, and creation of daily life for the Featherstone laid the foundation of aesthetic theory, but he did not think life is a tool that strict control of rational consumer space, but also  do not think life is a fragment of a fragmentation.   Featherstone believes that everyday life is consumer spending the main field of practice, and in this field, the emergence of consumer practice of aesthetic tendencies. Featherstone follows the performance of the control and resistance theory. practice in the analysis of consumption during the fight right to speak, on the one hand explains how to control the ideology of everyday life cultural practices of consumers, but also pointed out how consumers the possibility of a boycott., on the whole, daily control of the consumer ideology is growing, but from specific consumer practice, consumers have been symbols of consumer culture transformation and substitution.  Mike Featherstone lamented that some disorder of literature, Michael Gurevitch, Culture, Society and the Media Michael Gurevitch based on the world, from an interdisciplinary and cross-cultural perspective of globalization and democratization of the media between the complex and sometimes mutually reinforcing and sometimes conflicting multi-faceted relationship.   This book proposed a new theory about generalities, but not to provide a description of the micro, but the relevant proposition was different theoretical and historical sort, from which new problems.   firstly discusses the theory of globalization and the globalization of media organizations in the media, marketing, form, movement, effects and management aspects of change, and the media bottom-up globalization process and practice.  Then, the article in English literature of the existing market liberals, liberals in the public domain, and the radical democrats of different concepts of democracy and the spread of globalization and its significance for the different media analysis were reviewed, Finally, the book was put forward, including media ownership diversity, multi-directional flow of the global media in the political and theoretical significance, the Western model and views the adequacy or relevance media for political information than the broader identity  role during the formation of macro issues such as 7, to promote the breadth and depth of study.  The globalization and democratization of media there are complex interactions between the relationships between two, which is far from even a discussion of two books could come to an end.   Oliver Boyd-Barrett, Terhi Rantanen. The Globalization of News   Oliver Boyd-Barrett, Terhi Rantanen research from the social perspective ,and emphasizes the role of government era of globalization, and the Government can play a complementary effect and the market potential to give more attention. Using of statistical methods proved that external risks can not be ignored, but the state is playing an important integral role in providing social security and protection of social justice. Government maintains economic openness and balance between domestic needs of the community as a crucial and irreplaceable role.  The implication is: If the Government is up to the role that globalization will be able to smooth the contrary, this process will be reversed.     Oliver Boyd-Barrett,Terhi find some latest new which find the process of globalization, which in many ways is very different.  For example, todays international financial system from the conclusions of historical research in analysis and interpretation should be applied to contemporary events, there will be quite limited indeed.  But the basic values of the market mechanism and social hundred years did not occur in a large change fundamentally.  Since the markets expansion on a global scale in fact has brought individuals and the income gap between countries and the widening gap of economic welfare, just as happened 80 years ago as; it will be useful to draw lessons from history. How is Hamlet Character Influenced by Greek Philosophy? How is Hamlet Character Influenced by Greek Philosophy? Hamlet, protagonist of Shakespeares tragedy of the same name, is one of the most ambiguous and enigmatic characters of the history of literature. He is a thinker, and extremely philosophical, meditative and suspicious, indeed, he is always pondering about question with no answer. His monologues are very contemporary, because they are about psychological struggles that are still unresolved. His character is strongly influenced by philosophy and, particularly, by Greek philosophy. We can understand that Hamlet was interested in Greek culture by his numerous references to Greek mythology, and by the main topics of his soliloquies: the conflicts between right and wrong, thought and action, life and death, and the importance of the mind and thoughts of an individual. They all refer to important philosophical concepts of Greek philosophy, such as relativism, skepticism and humanism, which are rooted in ancient Greek philosophers thoughts and studies. About the references to Greek mythology, we can observe citations about many characters belonging to myths. Hyperion, Satyr, Niobe, Hercules (Act I, Scene II, 140-153), where Hyperion is a Titan or a byname of Helios, God of the sun; a Satyr is a lecherous creature, half-man and half-goat; Niobe was the Queen of   Thebes, who wept for her dead children even when she was turned to stone; and Hercules is a mythical Greek hero, notorious for his strength. Nemean lion (Act I, Scene IV, 83), which was a vicious monster who lived at Nemea. Priam, Hecuba (Act II, Scene II, 422-459), where Priam was the King of Troy during the Trojan War, and Hecuba was his wife. From this analysis, we can observe that not only was he interested in Greek mythology, but also on Greek literature, indeed, he probably read Homeric poems, Iliad and The Odyssey. Another evidence that Greek philosophy influenced Hamlet is that he often refers to Relativism. For example, when he says to Rosencrantz: there is nothing either good or bad, but thinking makes it so (Act II, Scene II, 240), he is referring to the Sophist theory that the truth or justification of moral judgments is not absolute, but relative to the moral standard of some person or group of persons1[1]. Another example is the most iconic monologue of the tragedy: To be, or not to be: that is the question: / Whether tis nobler in the mind to suffer / The slings and arrows of outrageous fortune, / Or to take arms against a sea of troubles, / And by opposing end them?. Hamlet is struggling whether is more noble to kill himself or to continue living though the problems he is facing. We can consider this as a form of moral relativism because, from Hamlets perspective, even something collectively thought as so morally incorrect like suicide can become correct, noble. According to Protagoras , a pre-sophist philosopher, The human being is the measure of all things, of those that are, that they are, and of those that are not, that they are not. By this, Protagoras apparently meant that each individual person is the measure of how things are to that person: things are or are not, to me, according as they appear to me to be or not be. Briefly stated, moral relativism is the view that moral judgments, beliefs about right and wrong, good and bad, not only vary greatly across time and contexts, but that their correctness is dependent on or relative to individual or cultural perspectives and frameworks.2[2] We can also consider the same monologue as an example of skepticism, because Hamlet is fond of pointing out questions that cannot be answered because they concern supernatural and metaphysical matters. Hamlets monologue What a piece of work is a man! / How noble in reason! how infinite in faculty! in form and moving how / express and admirable! in action how like an angel! / in apprehension how like a god! the beauty of the / world! is an evidence of another philosophical trend: Humanism. Even if the word Humanism was invented by Latins (Humanitas), we can observe Humanist thoughts in Sophist philosophers, Socrates and Plato. In that period, indeed, the subject of the philosophical speculation changed from transcendental topics, like Gods or the origin of the universe, to the human being. They became interested in human mind and experiences, and related topics such as ethic and ideas. To understand Hamlets tragedy deeply, first we have to understand its historic, religious and philosophical context. From the philosophical point of view, I found evidence of many philosophical trends influences, to both Hamlets character and Shakespeare, but I can state that most of them are related to the most important Greek philosophical trends.

Judging Books By Their Covers :: Essays Papers

Judging Books By Their Covers In every bookstore across America, people are faced with the tough question of what book should be bought. There are millions of books resting on shelves everywhere but what makes a reader pick up a novel to buy and read? Looking at book covers people can get ideas about what type of book is in their hands. Most books grab their audience by the way that they look on the outside. Many different authors and publishers choose famous works of art or use book reviewer’s comments to grab a specific audience for their book. When children are looking for books, they choose a book because of what is on the cover. Parents can view the cover as appropriate for their child. It is the cover that initially grabs the attention. Even as children grow up and begin reading books with few to no pictures, it is still the cover that says what kind of book it is. When I was in the library, I found a book about the history of book jackets. Although most of the information in the small book was unnecessary, I did learn some of the history behind book jackets. Although the people of today look at book covers to get some idea of the contents of the book, back in the eighteen hundreds books had jackets so that the pages would not get dusty or dirty. Some books had covers made of leather but usually these were books, like the Bible, that needed protection. The bookseller put the jacket on before it was placed on the shelf. These dust jackets had no title or writing on them until the middle of the eighteen hundreds. It was not until almost nineteen hundred that authors or publishers designed book covers with illustrations or with the title. This is different from today because most authors give their book’s cover as their trade marks so they can be easily recognized. Usually the artist draws the cover to the author’s liking. The artis t takes the words and changes them to an image suitable for the book. Catcher In The Rye, is a classic example of a book that has its cover as its trademark. The cover of the book is unique with its red background and yellow writing. Both the front and the back of the book are the same with no other writing but the title and the author’s name.

Airline Demand Forecast

STIMATION OF AIR TRAVEL DEMAND IN TURKEY ENAR TUNC, Orhan sIvrIkaya* Okan UNIVERSITY Title: ESTIMATION OF AIR TRAVEL DEMAND IN TURKEY Orhan Sivrikaya*(Candidate Phd. ), OKAN UNIVERSITY Tel: 0-532-4265392 Fax: [0-212-4652299] Email: [email  protected] com Enar Tunc, Professor of Industrial Engineering, OKAN UNIVERSITY Keywords * Domestic Air Transportation, City Pair, Origin and Destination, Demand, Forecast, Gravity Model, Multivariate Regression and Detour Factor. Total Page: 11 AbstractAccuracy in estimating airline market demand is a key element while an airline is planning its short term or long term business plan regardless of its status quo being an incumbent or startup company. Turkish domestic market of air travel industry has been dramatically grown in recent years especially after the deregulation commencing on the renewal of air transportation policy in 2003. However there is not any relevant scientific research in the literature to analyze the determining factors on air travel demand of domestic city pairs in Turkey.A multivariate regression model is generated in order to fit the air travel demand in number of passengers carried. The model is based on aggregate individual market which consists of on-line city pairs. The model is found significantly representative within the experimental data out of the years 2008 and 2009 including the origin and destination pairs for 40 on-line cities. Then, the model is tested by using 2010 figures in order to compare prediction values with actual figures. Accuracy level is found to be encouraging for potential new airports or potential new routes to be evaluated by using the model estimates. . Introduction The deregulation of air transportation market in Turkey in 2003 has started revolutionary changes in the airline industry. New government having the target to increase the portion of air travel out of all modes of local transportation attempted to encourage more airline companies to enter the market and enabl e them to offer more attractive prices by tax cutting specific to the airline sector. Price oriented competition has worked very well to generate significant airline passenger traffic.Low Cost Carriers have contributed to exercise a sustainable two digit growth by stealing passenger traffic from bus transportation as a result of shortening the gap between relative prices. Turkish Airlines as a legacy carrier has responded to structural changes in the market by applying dynamic pricing policy and growth strategy to benefit from economies of scale resulting in increase in productivity. Big changes in airline passenger traffic in Turkey create a challenge to testify any claiming model built to estimate air travel demand. Macroeconomic or demographic changes do not seem to be responsible for whole boost in air travel demand.Competition doubled or tripled available seat capacity on some routes so that it was required a different strategy to generate additional demand to achieve in satisf actory load factor which is a key performance indicator for airline profitability. Airline traffic is most of the time considered as a significant indicator for the performance of the nation’s entire industry since it is highly correlated with the number of business events and interactions with other industries simultaneously. So, it implies that changes in economies may influence airlines traffic indirectly.However, airline specific parameters like ticket price and degrees of competition are also supposed to be main driver for passenger demand besides the macroeconomic factors. The sustainable success of any organization or company is closely related with how well management or decision makers are able to foresee the future and develop appropriate strategies. The objective of this study is to examine the demand size for air transport in Turkey and show its implications for air transport planning. 2. BACKGROUND It has been seen throughout the results of the previous research in the iterature that one of the most important issue to develop a predictive model is to choose the right combination of the variables which represent the determining factors involved in the model. These variables are categorized by two subgroups (Carson et al. 2010): 1. Geo-economics Factors: which consist of geographical characteristics, economical activities, social factor etc. 2. Service Related Factors: which are related to airline dependent factors. The other prominent aspect of model generation is the level of forecast which can be classified by two groups as well; 1.Microscopic Model: Airport specific or city pair specific data is involved such that it refers the total number of incoming and outgoing passengers per particular airport or per city pair. 2. Macroscopic Model: Region or country specific data is involved such that it refers to aggregated number of passengers in a region or country regardless of origin or destination city. Aggregate Individual Market (AIM) foreca st outperforms the aggregate approach since the forecasting power gained by exploiting heterogeneous information across markets dominates the forecasting power lost due to estimation of many coefficients (Carson et al. 2010).Local area information appears to be more relevant in determining local O&D travel than of national information such as gross domestic product (Bhadra 2003). ————————————————- 3. OVERVIEW OF THE determ? nants for air passenger demand ? n turkey Turkey is spread over a wide geographical area and road ways are not adequately constructed for all direction. Hence, air transportation is supposed to have more shares out of total statistics in domestic transportation covering all possible city pairs. While the gap between relative prices is being shortened, more and more people find it affordable to fly.This study is aiming to find out the determining fac tors which are concerned to turn potential demand into air travel passengers. The proposed model is not only to explain actual traffic results but also to estimate potential traffic between cross cities which are not connected directly or to evaluate off-line cities to build new airport. Population, gross domestic product per capita and employment rate are considered as the leading macroeconomic dynamics behind air travel demand as depicted in the Table 1. Average fare has a stimulating effect on airline demand as Brons et al. 2002) pointed out that ticket price is an elastic driver for airline demand generation. There are also specific indicators for a particular city pair traffic representing interactivity between the concerning cities such as distance and number of migrants from each other. The number of bus registered in a city is indicating the volume of bus transportation which is considered to be negatively related with air travel demand. Since number of carriers as a degree of competition contributes to market expansion, it is also embedded in the model expecting a positive relation with air travel demand.Table 1 Commonality in Types of Variables Variable’s Name| Percentage of Occurrence*| GDP| 50. 0 %| GDP per Capita| 35. 7 %| Unemployment Rate| 14. 3 %| Fuel Price| 7. 1 %| Number of Employees| 7. 1 %| Population| 42. 8 %| Average Fare| 57. 1 %| CPI| 14. 3 %| Trade per Capita| 14. 3 %| Exchange Rate| 14. 3 %| Service Frequency| 28. 6 %| Distance| 42. 8 %| Expenditures| 7. 1 %| * The percentages are calculated out of a sample of 14 different relevant articles. Most of the itineraries between city pairs are not directly connected that means air passengers travel with connecting flights via one or more transfer points.If there is no direct service the dummy variable transit gets 1 and 0 otherwise. Naturally, passengers would not prefer to fly with connecting flights so it is anticipated to be negatively affecting air travel demand. 4. ECONOMETRIC ESTIMATION data, Methodology and results Data availability is main issue when data coverage is decided. Experimental model is based on the data of the two years 2008 and 2009 since all explanatory variables are available within the specified period. There are 40 on-line destinations in domestic network in Turkey.This number of destinations can theoretically generate 1560 different origin and destinations (O&D’s) on which direct or connecting flights are possible. However experimental sample does not cover data for all possible on-line O&D’s because some city pairs which are at close distance are not meaningful to fly with connecting flights or the concerning flights are not connected each other. There are 231 city pairs which are served with direct flights, whereas the remaining city pairs are found to be flown by connecting flights via an appropriate domestic hub.Under the assumption of approximately the same number of O&D’s for each year, data size will be duplicated for the two year’s period. Airport statistics for all scheduled carriers are used in the experimental model as a source of the dependent variable. Transfer traffic is removed from the statistics for each city pair, since the proposed model is to estimate pure O&D passenger by using data specific to the corresponding city pairs. Average prices for each city pair are estimated by using airlines’ web site. Road distance between the cities is taken from the web site of the General Directorate Highways of Turkey.Population of the cities, GDP per capita of the cities, the number of migrants between the cities, the number of bus registered in the city’s account and labour rate of the cities are obtained from the Bureau of Statistics in Turkey. Weighted average of the corresponding city’s population is used, while GDP per capita and the labour rate are being converted to O&D level. A variety of different models exist for passenger volu me estimation. Since no single model guarantees accuracy, airlines in fact compare forecasts from several different models.Within this set of forecasting methods, the most demand models used are of the simple gravity type formulation. (S. C. Wirasinghe et al. 1998). The gravity model for the estimation of domestic passenger volume between city-pairs is examined in this study. By excluding unavailable service-related or market specific input variables, and using cross-sectional calibration data, the model is particularly applicable to city-pairs where no air service exists, historical data is unavailable, or factors describing the current service level of air transportation are not available.Average price for city-pairs with no air service is estimated by fall back mechanism that it uses the average price which is normalized by distance of the cities having similar market structure. All other explanatory variables are not service related factors and available for the city-pairs with no air service. The gravity model takes the form: D=?. AaBbCc†¦ This model assumes that the marginal effects of each variable on demand are not constant but depend on both the value of the variable and the values of all other variables in the demand function (Aderamo 2010).In other words, the explanatory variables affect demand in multiplicative manner. Partial derivation of any independent variable proves aforementioned relationship. However, this model can be made suitable for multiple regressions by applying logarithmic transformation. Logarithmic form of the gravity model takes the form: LogD=? 0 + ? 1LogA + ? 2LogB + ? 3LogC +†¦ where ? 0=Log? It is obvious that interdependency is resolved in this form so that multiple regression model can be applied. The proposed multiple regression model is generated by using SAS Jmp 9 tool.Table 2 shows the matrix of correlation between the independent variables. The results show that some of the variables are interrelated. For exa mple, Log_Migrant has a correlation coefficient of 0. 8661 and 0. 8150 with Log_Pop* and Log_Bus* respectively. Where both Log_Migrant* and Log_Pop* are calculated by taking the product of population of origin and destination cities. However, omitting any of these two variables would substantially reduce the model fit. As the goal is to obtain a reliable estimation of the passenger volume, all interrelated variables were included (Grosche et al. 007). Furthermore, it has been said that if the sole purpose of regression analysis is prediction or forecasting, then multicollinearity is not a serious problem because the higher R2, the better prediction(R. C. Geary, 1963). In order to verify stepwise regression fit of the model, stepwise process by backward direction and minimum AICc selection is used. When all independent variables as depicted in Table 2 are entered, the smallest AICc value 2665. 913 is found. Adjusted R2 as shown in the Table 3 is 0. 823991 which is fairly good.In the Table 4, adjusted R2’s are compared including the relevant articles in the reference list. This comparison table shows that the studied model efficiency is relatively successful. As shown in the table 5, the F test also shows that the regression is significant since F statistic of 497. 2411 is obviously higher than the critical value of 2. 32 at 0. 01 level of significance. In the table 6, parameter estimates are depicted. As seen in the table, all independent variables are significant at 0. 01 level of two tail significance considering their t-statistics.Since the coefficients of the regression model represent elasticities of the corresponding variables, how change of any variable affects demand estimation can be determined. The price elasticity of passenger demand is approximately -1. 1 which implies that airline passenger demand in Turkey is elastic. This finding is compliant with the fact that after low cost carriers entered into the market by lowering ticket prices, mark et size has been tramendously enlarged. Domestic passenger traffic grows higher than the decreasing rate of ticket price.Both GDP per capita and ticket price seem to have elastic impact on passenger demand estimation. Air transportation and bus transportation seem to be competing each other because of their negative relation. When air service is provided by connecting flight which means transit traffic, air transport demand is decreasing. This result is not surprising because people do prefer to fly directly. Another result is that the number of airlines participating in each O&D market tends to have a positive impact on the number of passengers traveled between O&D pairs, perhaps representing the ffects of choice more than anything else. Lastly, distance and the number of migrants are found positively related with air transport demand as expected. Table 4 Model Efficiency Benchmark| Research Name| Level of Forecast| Author| Year| Independent Variables| Observation| Adjusted R Square| Demand For Air Transport In Nigeria| Aggregate| Adekunle J. Aderamo| 2010| Index of AgricultureIndex of ElectricityGDP| 23| 0. 923| Air Travel Domestic Demand Model in Bangladesh| Aggregate| Md. Jobair Bin Alam Dewan Masud KArim| 1998| PopulationGDPDistance| 31| 0. 8| An Econometric Analysis of Air Travel Demand in Saudi Arabia| Aggregate| Seraj Y. Abed Abdullah O. Ba-FailSajjad M. Jasimuddin| 2001| PopulationTotal Expenditures| 25| 0. 959| Regression Model for Passenger Demand: A case study of Cairo Airport| Aggregate| Dr. Khaled A. Abbas| 2003| Population GDPForeign Tourist| 88| 0. 82| Demand for Airravel In USA| O&D| Dipasis Bhadra| 2003| Density, Interaction, Distance, Marketshare, Fare| 2424| 0. 57| An Aggregate Demand Model in Hub-and-Spoke| Aggregate| Wenbin WeiMark Hansen| 2006| Frequency, Number of Spokes, Fare, Distance, Capacity, Traffic Type| 897| 0. 92| Gravity Model for Airline Passenger Volume Estimation| City-pairs| Tobias GroscheFranz RothlaufArmin He inzl| 2007| DistancePopulationCatchment Area| 956| 0. 761| The number of migrants indicates the relationship between city-pairs hence it positively affects on point to point air traffic demand. When distance is greater, air transport demand increases due to the fact that people get higher utility comparing to the alternative modes of transportation. In the figure 1, model fit of the experimental data is shown in scatter diagram. There are total 955 observations within experimental data.A test data is obtained from 2010 actual results which consists of 562 observations. The model predicts 2010 figures with a Mape (Mean Absolute Percentage Error) value 14. 1 %. Actual data of 2010 is refined by excluding the O&D’s having less than 104 yearly passengers flow and detour factors smaller than 3. Logic of this filtering is to choose meaningful connections out of the all itineraries. Although the model is performing significantly well with a relatively high Rsquare value, small d iscrepancy in prediction value may result in larger inaccuracy in passenger demand estimate because of logarithmic aspect of the regression. . CONCLUSION This study demonstrated that the proposed econometric estimation and using micro data based on local area information can result in substantial insights to O&D travel. The demand model reveals all the quantitative relationships among the used variables, which is helpful for airlines to understand the consequence of change of their decision variables or adjustment of their routing structures, and also useful for the related authority to quantify the benefits of airport capacity expansion and to take into account while airport building plan is being evaluated.It would be advantageous to extend the time period covered by the analysis. This would enable to examine possible differences in elasticity amongst city-pairs. Extending the data back in time would also provide observations of airfares progress. The model efficiency may be i mproved for even more reliable estimation, if more independent variables indicating bilateral relations between city-pairs are embedded in the model such as the number of call between city-pairs or credit card statistics of domestic visitors. References S. C. Wirasinghe and A. S. Kumarage, An Aggregate Demand Model for Intercity Passenger Travel in Sri Lanka.Transportation 25: 77-98, 1998. R. C. Geary, Some Results about Relations between Stochastic Variables: A Discussion Document, Review of International Statistical Institute, Vol. 31, pp. 163-181, 1963. Richard T. Carson, Tolga Cenesizoglu and Roger Parker. Aggregate Demand for USA Commercial Air Travel. Department of Economics, University of California. 2010. Elton Fernandes and Ricardo Rodrigues Pacheco. Air Transportation Analysis: Passenger Demand in Brazil. Aerlines Magazine e-zine edition, issue 33. Adakunle J. Aderamo. Demand for Air Transport in Nigeria. Journal of Economics, 1 (1): 23-31 (2010).Md. Jobair Bin Alem and De wan Masud Karim. Air Travel Demand Model For Domestic Air Transportation in Bangladesh. Journal of Civil Engineering The Institution of Engineers, Bangladesh Vol. CE 26, No. 1, 1998. Seraj Y. Abed, Abdullah O. Ba-Fail and Sajjad M. Jasimuddin. An Econometric Analysis of International Air Travel Demand in Saudi Arabia. Journal of Air Transport Management 7 (2001) 143-148. Abdullah O. Ba-Fail and Seraj Y. Abed. The Determinants of Domestic Air Travel Demand in the Kingdom of Saudi Arabia. Journal of Air Transportation World Wide Vol. 5, No. 2 – 2000. Abdullah Omer Ba-Fail.Applying Data Mining Techniques To Forecast Number of Airline Passengers In Saudi Arabia (Domestic and International Travels). Aviation Institute, University of Nabraska at Omaha, 2004. Senanu Ashiabor, Hojong Baik and Antonio Trani. Logit Models For Forecasting Nationwide Intercity Travel Demand in the USA. Journal of the Transportation Research Board, No. 2007, Washington, D. C. , pp. 1-12 2007. J. Scott Arm strong and Michael C. Grohman. A Comparative Study of Methods for Long-Range Market Forecasting. Management Science, 19 (2), pp. 211-221 1972. Khaled A. Abbas. Conceptual and Regression Models for Passenger Demand Prediction.Aerlines Magazine e-zine edition, issue 26 2003. Dipasis Bhadra. Demand for Air Travel in the United States: Bottom-up Econometric Estimation and Implications for Forecasts by Origin and Destination Pairs. Journal of Air Transportation Vol. 8, No. 2 – 2003. Radosav B. Jovanovic. Generalised Intrinsic Characteristics as a Forecasting Tool: A dynamic perpective. Second International Conference on Research in Air Transportation – Belgrade, June 24–28 2006. Martijn Brons, Eric Pels, Peter Nijkamp and Piet Rietveld. Price Elasticities of Demand for Passenger Air Travel. Journal of Air Transport Management 8 pp. 65-175 2002. Dail Umamil Asri and Yoriyasu Sugie. Simultaneous Demand Model for Passenger Travel. Proceedings of the Eastern Asia Society for Transportation Studies, Vol. 4, October, 2003. Joyce Dargay and Mark Hanly. The Determinants of the Demand for International Air Travel to and from UK. ESRC Transport Studies Unit, Centre for Transport Studies, University College London, November 2001. Catherine Zhukovskaya. Use of the Generalized Linear Model in Forecasting the Air Passengers’ Conveyances from EU Countries. Computer Modelling and Technologies, Vol. 11, No. 1, pp. 62–72, 2007. Wenbin Wei and Mark Hansen.An Aggregate Demand Model for Air Passenger Traffic in the Hub and Spoke Network. Transportation Research Part A 40 pp. 841–851, 2006. Matthew G. Karlaftis. Demand Forecasting in Regional Airports. Straer 7 pp. 100-111, Tr. 312, 2008. Tobias Grosche, Franz Rothlauf and Armin Heinzl. Gravity Models for Airline Passenger Volume Estimation. Journal of Air Transport Management 13 pp. 175-183, 2007. Chaug-Ing Hsu and Su-Miao Liu. Predicting City-Pair Air Passenger Traffic Using Grey Topological F orecasting Model. Journal of the Eastern Asia Society for Transportation Studies, Vol. 5, October, 2003.

Bombs on Japanese Essays

Bombs on Japanese Essays Bombs on Japanese Essay Bombs on Japanese Essay A figure of analyses have been conducted on the bombing action that was carried out in the month of August the twelvemonth 19 40 five by the US on Nipponese metropoliss. This bombardment was really important since it resulted to a really big figure of deceases and farther effects which are still apparent in some people including those caused by radiation. The chief ground as to why this action has attracted a broad scope to philosophical analysis is that ; despite the fact that so many people died from the bombardment. US authorities still keep it that their action was grounded on morality. They argue that they had saved greater harm from ensuing from war and should be thanked instead than condemned. ETHICS ANALYSIS Introduction When Second World War was coming to an terminal. US grew impatient and decided to rush up its stoping. US made usage of atomic bombs to assail Japan which managed to kill a big Nipponese population and injuring a larger figure as good. This action carried out by US has been widely analyzed by philosophers with John Stuart being one of them. John has based his analysis on the bombardment morality which contributes to a deeper apprehension of events that took topographic point. causes every bit good as effects that accompanied the action. He begins with observing that the bombing action was among the most important events that took topographic point during the Second World War. The existent bombardment took topographic point in two topographic points ; one was dropped in Nagasaki while the other bombardment took topographic point in Hiroshima. Two hundred thousand people died instantly the bombardment was carried out while about one hundred and 30 thousand more people lost their lives in a period of five old ages that followed. The subsequent deceases were caused by aftermath effects of bombing including injury and radiation. Further more. about three hundred thousand people are found to endure from bombing effects in several ways including disablement. Daniels ( 2008 pp 37-40 ) Morality of US Bombings on Japan Despite the fact that bombing caused great harm on Japan citizens. American authorities has non taken a minute to apologise for its annihilating actions. On the contrary. Americans led by Harry Truman have opted to warrant their actions giving moral grounds as to why they attacked Japan even after they had lost war. One such case where this has happened is when Truman was composing about the issue in 19 50 eight where he commented that he did non hold any reserves refering the bombardment. These words reached the Japanese in good clip and metropolis council of Hiroshima criticized Truman’s words observing that they signified great befoulment to people affected by the bombardment. Alternatively of worsening his statement. Truman arranged a meeting where he addressed an American imperativeness conference sketching justification for bombardment. He said that Japan tempted the US to move since they had attacked them at the Harbor of Pearl earlier before the bombardment and this was merely a pay back . Truman’s remarks were backed by other Americans who were eager to demo the morality of bombing among them being Paul Fussell. who had a incredulity in war. Paul argued that retaliation from US did non stand for a sensible motivation though it was still America’s motivation when it was destructing Nipponese Empire. Paul besides point out on disbelieve on Americans who regard the 19 40 five bombardment as an action of force that they did non back up since during the existent clip of bombardment. about every American was delighted. The delectation did non merely come from the fact that war period was shortened which saved a great figure of Americans from diing but besides for the ground that Nipponese deserved to be punished for assailing American military personnels at the seaport of Pearl. More grounds. of Americans’ delectation was noted where about 20 three per centum of them suggested on dropping of more bombs on Nipponese. Mearsheimer ( 2001 pp 17-24 )

LSD Psychotherapy essays

LSD Psychotherapy essays The United States Drug Enforcement Agency, the DEA, classifies LSD as Schedule I controlled substance. Schedule I controlled substances are considered the most dangerous drugs in the known pharmacopeia. LSD shares its Schedule I classification with harmful substances like heroin and MDMA, commonly known as Ecstasy. Drugs classified as Schedule I substances have no known or no established medical uses but have a high potential for abuse and harm. Therefore, in the interests of public safety the Drug Enforcement Agency strictly prohibits the manufacture and distribution of LSD (lysergic acid diethylamide-25). The drug was first synthesized in 1938 and was classified as a Schedule I controlled substance in the late 1960s. In 1938 a Swiss chemist named Albert Hoffman synthesized over two dozen compounds from ergot, a fungus that grows on rye grass. Hoffman developed ergot-derived alkaloid molecules for therapeutic purposes working for the Sandoz Corporation pharmaceutical laboratory. Grof notes that the ergot alkaloids were studies as drugs that can induce uterine contractions, stop gynecological bleeding, and relieve migraine headache. The 25th in a string of ergot alkaloids was what is commonly known now as LSD. Hoffman accidentally came into contact with the substance. The chemist experienced a profound transformation to his perceptual, cognitive, and emotional states and recorded his experiences in a journal. Grof cites Hoffman, who was seized by a peculiar restlessness, like a a kind of drunkenness... which was characterized by extreme activity of the imagination. The following day Hoffman deliberately ingested 250 micrograms of the same substance in an experimental fashion and experienced a far more intense hallucinatory experience (Grof). Hoffmans phantasmagoric experiences with LSD have been echoed by countless of recreational drug users who have viewed the hallucinogen as anything fro...

Telecommunications in health care Essay Example | Topics and Well Written Essays - 500 words

Telecommunications in health care - Essay Example ose of this paper is to talk about examples of telecommunication used I the workplace, the advantages and disadvantages of telecommunication, and new developments expected in the sector. An example of telecommunication technology used in the place of work is telephonic nurse case manager. It is used for getting timely and cost effective results by communicating and negotiating with patients, their providers and employers. The claims management process is facilitated using electronic data interface, which downloads case process documents into the patient’s claims management system. The telephonic nurse case manager is beneficial because it enables the patient to receive the appropriate treatment for his or her injuries. It is also beneficial because the patient is able to go back to work as soon as possible: the telephonic nurse case manager has a return to work plan. The use of telecommunication has a lot of advantages (Suter & Johnston, 2011). Hospitals that use telemedicine achieve reduced costs in their operations (Suter & Johnston, 2011). Suter and Johnson describe how learning is easily done through actions compared to listening. Therefore, telemedicine has the benefit of teaching patients how to take care of themselves since they will have learned through actions. Telemedicine increases the number of patients attended to by a physician (Gorman, 2011). This addresses the issue where there are very few physicians attending to the increasing number of patients (Gorman, 2011). There is a two way interactive television with a patient at one end and a physician at the other (Gillette, 2003). This is useful when a patient is not able to travel to the urban area for treatment. The use of telecommunication technology in healthcare has disadvantages when it comes to delivering the required equipment to the patients home (Gillette, 2003). In America, some states do not allow physicians from another state to perform their services to other states (Gillette, 2003).

Politcal Science Essay Example | Topics and Well Written Essays - 500 words - 4

Politcal Science - Essay Example The global political economy is mostly concerned with the political forces shaping up the systems where economic interactions are detailed. The global political economy centers itself specifically on the debate regarding the globalization regimes, the international trade mechanisms, the global markets, the financial discussions, the socio-economic climates within the world, and so on. The concept is a new one as it was brought to light in the 1970s. Its origin was due to a heterodox approach towards the global studies during this era. It occurred somewhere between the 1973 world oil crisis and the Bretton Woods system breakdown which put a red alert on the face of academics within the United States of America in terms of economic foundations, contingencies and importance elements. The global political economy bases its origin upon a few scholars, most noteworthy of which is Eugene Low who described that earliest studies of international relations had emphasized a great deal on the excessive discussion of law, diplomatic history and politics (Viotti & Kauppi 2006). It was at the same time when neoclassical economics was being seen with a skeptical eye as it was accused of being ahistorical as well as abstraction. The origin drew heavily on the historical sociology as well as the economic history where the global political economy proposed a merger of economic and political discussions and the related analyses. Both the Marxist scholars as well as the global political economy ones protested against the dependence of Western social science towards the territorial state as being the unit of analysis and more than that focused on the adoption of a global system in place. The current political economy is such that there is immense room for growth and advancements within the different nations of the world. What is needed now is a concerted effort on the part of each and every player so that the international domains become quick