Taşımacılık modelleri, uluslararası taşımacılık konusuna yaklaşımlar ve bir uygulama

Ortaatila, Bahar
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Fen Bilimleri Enstitüsü
Günümüzde uluslararası ticaretin gelişmesi ve çeşitlenmesiyle paralel olarak uluslararası taşımacılığın önemi de giderek artmaktadır. Taşımacılık kavramı malların üretildikleri merkezlerden talep edildikleri merkezlere olan hareketini içerir. Bu akışın en uygun maliyet ve ulaşım süresi bileşeniyle gerçekleştirilmesi esastır. Bu amaca ulaşabilmek için tek bir taşıma türünün kullanılması özellikle uluslararası ortamda yetersiz kalmaktadır. Bu nedenle birkaç taşıma türünün birleştirilmesiyle oluşan bütünleşik taşıma giderek yaygınlaşmaktadır. Böylece maliyet ve performasta önemli faydalar sağlanmaktadır. Taşımacılık faaliyeti tek basma ele alınamaz. Lojistik sistemin diğer bileşenleri olan stok kontrol, sipariş alma, paketleme ve depolama ile sürekli etkileşim halindedir. Taşımacılık konusunda verilen kararlan etkilemeleri nedeni ile çalışma kapsamında uluslararası lojistik faaliyetleri hakkında da bilgi verilmiştir. Özellikle Türkiye gibi gelişmekte olan ülkeler açısından uluslararası taşımacılığın geliştirilmesine önem verilmesi daha da gereklidir. Taşımacılığın gelişmesi tüm ekonominin gelişmesini sağlayacak yolu açar. Bu durumda taşımacılık sektörünün anahtar sektör konumunda olduğu söylenebilir. Bu çalışma kapsamında taşımacılık alanında karar vermek için kullanılan çeşitli modeller incelenmiş ve Türkiye için taşıma türü bazında uluslararası talep tahmin modelleri kurulmuş ve TSP 7.0 paket programı kullanılarak regresyon yöntemine göre çözülmüş ve çıkan sonuçlar yorumlanmıştır.
International marketing is the performance of business activities that directs the flow of a company's goods and services to consumers or users in more than one nation. The only difference between domestic marketing and international marketing is the activities that take place in more than one country. While this difference may seem minor, it accounts for the complexity and diversity found in international marketing operations. Current interest in international markering can be explained in terms of changing competitive structures, coupled with shifts in demand characteristics in market throughout the world. For many business new market opportunities have to be sought if profit margins are to be maintained. Companies with only domestic markets have found it increasingly difficult to sustain customery rates of growth, and many are seeking foreign markets to absorb accumulating surplus productive capacity. Companies with foreign operations have found that earnings are soaring from previously neglected overseas operations and that the return on foreign investments is frequently higher than those in the home markets. Manifacturers invariably find it more difficult to distribute their products to foreign customers than to supply their home markets. International freigth xvu movements are generally longer, often involve the use of more than one transport mode and are subject to delay at national borders. Special care must be taken to insure that they conform to transport regulations in the countries through which they pass. To compensate for longer order lead times, international distribution channels generally contain more stock man their domestic counterparts. The main differences of domestic and international logistics are as follows: Costs, local environment, control, currency, communication. Since overseas markets involve greater distances physical distribution costs are higher. But the additional costs of servicing overseas markets involve more than those of physical distribution alone. Packaging costs, material handling equipment costs, administration costs, stock costs and working capital requirements are higher. The legal environment in an overseas market may determine the structure of the firm's logistic system. The shortage of information means that the inventory control system for overseas markets is likely to be less effective than in the home market making necessary higher levels of buffer or reserve stock. The movement of payment within the distribution channel is complicated in overseas markets by differing currencies and exchange complexities. Distance makes effective communication between supplier nad customer more diffucult This will be particularly important when the product supplied is complex and requires a high level of technical support and spare part provision. Among the very facets of developmental problems of the developing countries, transport problems comes in the first place. As the improvement of transportation systems played a major role in the development of the developed countries, it has to still assume the same functioning, but at a drastically greater magnitude. Therefore, the approach to the solution of the transport problems would inevitably differ between the developed and developing countries. xvin When we look at the transport sector's position in the context of developmental processes in developing countries, we can pinpoint some features of the transport within the general economic activity: Firstly, like all other sectors of the economy, the development of transport produces the same effects: contribution to the GNP (value added) and the employment Secondly, the development of transport paves the way for the development of the rest of economy or, the whole economy in general. In this sense transport is a key sector in the econmy. The industrial society rests on trade, that is on the movement of materials form where they found, to a processing point and then the finished product to the market It is only in very exceptional circumstances that the source of the raw materials, the manifacturing point and the market place are all in the same location. The usual situation is that they are geographically separated, and even where they are not, it is often happen that other areas may be able either to produce the same materials or finished products more cheaply than the one under consideration, or the market may be larger or more wealthy. In all of these cases the most important act that must take place if the economy is to develop is that of transportation and distribution. Without these the regions would have to rely solely on their local resources and markets. The proposition can be made that transport and distribution are the bridging costs between the costs of material and manifacture, nad the prices charged to the ultimate consumer. To say that transportation is logistics implies that is, transportation, operates independently of other logistics functions (storage, materials handling, inventory control etc.). Transportation has a direct impact upon nodal operations. The quality of link service provided over a link has a direct bearing upon inventory costs and/or stockout costs at a node as well as the cost of operating the node. -xix- The above statements are not to be construed to imply that transportation is a rather minor logistics function not deserving attention. This by all means is a false interpretation. Transportation decisions interact directly wiht other logistics elements as well as causing an impact among other elements. For example, if a firm decided to switch from rail to air transport to serve a given raw material source-plant link, the increased speed, lower transit time, of the air servise requires the holding of lower inventories to meet anticipated usage, less warehousing space, and less stringent product packaging resulting from a smoother movement by air. The lower inventory levels will reduce inventory insurance requirements, and capital tied up in inventory, thereby reducing inventory carrying costs. These advantages, effects upon other logistics function, are realized, however, at the cost of higher transportation costs. Thus, the transport decisions cannot be made in a vacumm; attention must be given to effect of the transport decision upon other elements in the logistics system-the application of the total cost or systems approach. In summary, transportation is a vital part of the logistics system, but it is not the only function in logistics. Transportation permits the firm to bridge the producer-consumer gap and thereby create time and space utility in goods. International transportation is of major concern to the multinational corporation because transportation determines how and when the goods will be received. Further, transportation costs represent 7 percent to 15 percent of the total landed cost of an international order, and therefore deserve major attention from a cost perspective. The three components of the transportation issue are infrastructure, the availability of modes and the choice of modes among the given alternatives. Transportation planning seeks the optimum quantity, timing and allocation of transportation investments in support of spesific development goals. The spesification of a transportation planning system and the description and evaluation of its performance is a complex task. Several economic and social factors, Travel costs, travel time, convenience, ecology XX- and the influences on the development of the economy, have to be considered. The basic purpose of the economic evaluation of a project is to measure its economic costs and benefits in order to determine whether its net benefits are as great as those obtainable from other marginal investment opportunities in the particular country. It is sometimes stated that the value of a project should be measured by its contribution to the growth of national income. Uncertainity pervades virtually all aspects of life. It is not to be expected that transportation would be an exception in this respect For decision making under uncertainty, three principal approaches have been adopted. The first, and most common, is implicit or explicit conservatism. Where doubts are felt about future, cost elements are tend to be biased upward and benefit elements downward in ways which are more or less arbitrary. A second approach to appraisal in the presence of uncertainty has been to convert an uncertain environment into one of risk by making some type of objective estimate of the probabilities of the future states of nature, after which an expected value maximisation approach is adopted. The third category of techniques for handling decisions under uncertainty are termed complete ignorance methods, since they assume no knowledge of the probabilities of future states of nature. In this study different transportation models have been introduced and application is made on transportation demand analysis. -xxi Transportation demand analysis is the process of relating the demand for transportation to the socioeconomic activities that generate it In this process, the type, level, and location of human activities are related to the demand for movement of people and goods between the different points in space where these activities take place. The results of this analysis are relationalships, often in the form of models, between measures of activity and measures of transport demand. The method employed in this study is the regression analysis using TSP 7.0 software package.
Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 1994
Anahtar kelimeler
Endüstri ve Endüstri Mühendisliği, Taşımacılık, Uluslararası pazarlama, Industrial and Industrial Engineering, Transportation, International marketing