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Wavelet Analyses of Oil Prices, USD Variations and Impact on Logistics
(American Institute of Physics, 2009) Melek, M.; Tokgozlu, A.; Asian, Z.; Aslan, Z.
This paper is related with temporal variations of historical oil prices and Dollar and Euro in Turkey. Daily data based on OECD and Central Bank of Turkey records beginning from 1946 has been considered. IDcontinuous wavelets and wavelet packets analysis techniques have been applied on data. Wavelet techniques help to detect abrupt changing's, increasing and decreasing trends of data. Estimation of variables has been presented by using linear regression estimation techniques. The results of this study have been compared with the small and large scale effects. Transportation costs of track show a similar variation with fuel prices. The second part of the paper is related with estimation of imports, exports, costs, total number of vehicles and annual variations by considering temporal variation of oil prices and Dollar currency in Turkey. Wavelet techniques offer a user friendly methodology to interpret some local effects on increasing trend of imports and exports data. © 2009 American Institute of Pliysics.
Criticality Investigations for the Fixed Bed Nuclear Reactor Using Thorium Fuel Mixed with Plutonium or Minor Actinides
(Pergamon-Elsevier Science Ltd, 2009) Sahin, Suemer; Sahin, Haci Mehmet; Acir, Adem; Al-Kusayer, Tawfik Ahmed
Prospective fuels for a new reactor type, the so called fixed bed nuclear reactor (FBNR) are investigated with respect to reactor criticality. These are (1) low enriched uranium (LEU); (2) weapon grade plutonium + ThO2; (3) reactor grade plutonium + ThO2; and (4) minor actinides in the spent fuel of light water reactors (LWRs) + ThO2. Reactor grade plutonium and minor actinides are considered as highly radioactive and radio-toxic nuclear waste products so that one can expect that they will have negative fuel costs. The criticality calculations are conducted with SCALE5.1 using S-8-P-3 approximation in 238 neutron energy groups with 90 groups in thermal energy region. The study has shown that the reactor criticality has lower values with uranium fuel and increases passing to minor actinides, reactor grade plutonium and weapon grade plutonium. Using LEU, an enrichment grade of 9% has resulted with k(eff) = 1.2744. Mixed fuel with weapon grade plutonium made of 20% PuO2 + 80% ThO2 yields k(eff) = 1.2864. Whereas a mixed fuel with reactor grade plutonium made of 35% PuO2 + 65% ThO2 brings it to k(eff) = 1.267. Even the very hazardous nuclear waste of LWRs, namely minor actinides turn out to be high quality nuclear fuel due to the excellent neutron economy of FBNR. A relatively high reactor criticality of k(eff) = 1.2673 is achieved by 50% MAO(2) + 50% ThO2. The hazardous actinide nuclear waste products can be transmuted and utilized as fuel in situ. A further output of the study is the possibility of using thorium as breeding material in combination with these new alternative fuels. (C) 2009 Elsevier Ltd. All rights reserved.
Identifying Effective Variables Using Mutual Information and Building Predictive Models of Sulfur Dioxide Concentration with Support Vector Machines
(Foundation Environmental Protection & Research-FEPR, 2010) Sakar, C. Okan; Kursun, Olcay; Ozdemir, Huseyin; Demir, Goksel; Yalcin, Senay
Sulfur dioxide (SO2) is an issue of increasing public concern due to its recognized adverse effects on human health. Therefore, accurate SO2 prediction models are very important tools in developing public warning strategies. The goal of this study is to identify the relevance of meteorological and air pollutant variables using a classical and widely used measure of dependence, Shannon's Mutual Information (MI), and to build an accurate SO, prediction model using the relevant variables as inputs. Specifically, features ranked by MI measure are tested on how much joint predictive power they have of the target using a popular machine learning tool, support vector machines (SVM), and in comparison to multilayer perceptron (MLP), which is the most commonly used machine learning tool in previous studies for the prediction and analysis of air pollutants. It was found that the SVM model gave a higher correlation coefficient (r) and less root mean squared error (RMSE) than MLP for both test and validation sets. The predictive model used 6 input variables for both data sets as the relevant features for maximum SO, concentration prediction at time t+1, which are the average SO,, maximum SO2, outdoor temperature (OT), average nitrogen dioxide (NO2), average ozone (O-3), and average wind speed at time t. The results of this study indicate that MI can be used efficiently in determining the importance of input variables in the prediction of SO2 concentration and SVM is a popular machine learning tool well suited for use in air pollution modeling.
Using TOPSIS Method with Laplace Criterion to Select Optimum Airline
(Iura Edition Spol Sro, 2010) Eker, Ipek; Turan, Gokhan; Ergin, Ayfer; Alkan, Guler
In this study, for evaluating subjective features that provides preference of airline companies to others the method TOPSIS has been used. Whilst calculating the weights of the criteria Laplace Criterion had been used. The importance of the study is that this is a unique application in air cargo industry.
Türkiye'nin iktisadi ve siyasi tarihinde toprak reformu tartışmalarının rolü
(2010) Önal, Nevzat Evrim
Toprak reformu tartışması, Türkiye Cumhuriyeti'nin kuruluşundan itibaren aralıklı olarak gündeme gelmiş ve gündeme geldiği her dönemde iktidarı elin¬de tutan mülk sahibi sınıfın iç kompozisyonunda, kentli sermaye sahipleri ve büyük toprak sahipleri arasındaki dengeler üzerinden geçici bir çözüme ulaş¬mıştır. Giderek şiddetlenen tartışma, çok partili rejime geçişle birlikte ülke siyasetindeki temel taraflaşmanın fay hattını oluşturmuş; Cumhuriyet Halk Partisi ile Demokrat Parti arasındaki ayrışmanın merkezinde kentli burju¬vazi ile büyük toprak sahiplerinin çıkarları arasındaki farklılıklar durmuştur. Tartışma, herhangi bir belirleyici sonuca ulaşmamış, daha çok büyük toprak sahiplerinin tedricen burjuvalaşması ve kentlileşerek topraklarına yabancı laşması sonucunda sönümlenmiştir. Bu bakımdan toprak reformu tartışması, Türkiye siyaset tarihinin en önemli başlıklarından birini oluşturmaktadır ve bu konuda yapılacak kapsamlı bir analiz yoluyla Türkiye toplumunun sınıfsal gelişimi hakkında çok önemli bulgulara ulaşmak mümkündür. Bu çalışmanın amacı, Türkiye 'de kapitalizmin, modern toplumsal sınıfların ve siyasi iktidarın gelişimini toprak reformu bağlamında ele almaktır.
The Forest Products Industry in Turkey
(Academic Journals, 2011) Aksu, Baki; Koc, K. Huseyin; Kurtoglu, Ahmet
This study was conducted to analyze the structure of Turkey's wood products industry and to suggest ways to improve the country's competitive position in global markets. The 415 largest solid wood manufacturers were surveyed using questionnaires administered in personal interviews and by mail. Results reveal that forest product enterprises are geographically clustered in a few provinces. Thirteen percent of respondents are using outdated technology while 63% are using relatively new technology and 24% are using advanced technology. The 2001 economic crisis seriously affected the wood products industry with a 38% decrease in the number of employees and a number of shuttered facilities. Overall, the research indicates that the Turkish forest products industry is fragmented and is experiencing a number of obstacles to further development. Turkey has an established but generally inefficient forest products industry. This article gives an overview of the sector and offers recommendations for improvement. Results from this study can be useful to manufacturers and policy makers in Turkey and other countries with similar industry structures in short and long-term sectoral planning and development.
An Evaluation on Growth Potential of the Small and Medium Scale Enterprises (SME) in Turkish Furniture Industry
(Academic Journals, 2011) Aksu, Baki; Koc, K. Huseyin; Karademir, Devrim
With its increasingly expanding uses, the furniture industry has become a basic industrial sector in the world, especially in the developed countries, and it represents 2% of the total labour and 2% to 4% of the total production. The global foreign trade of furniture was around $174 billion in 2008. Though it has been growing fast, the furniture industry in Turkey is far from the level in the developed countries. In regard to the Turkish furniture industry, 99% of which consists of small and medium scale enterprises, just like all the other industries, few data are needed to be able to make accurate evaluations. The current conditions in the small and medium scale enterprises have been neatly described in this study. It tries to offer solutions to the problems, analyze the competition opportunities and shed light for future studies by eliminating inadequate data. It is the first study in the field since there has not been such research which covers the whole country except for the regional ones. Also, this project is supplementary to the studies carried out by the researchers on the large-scale enterprises, the whole industry is analyzed.
Feature Selection for the Prediction of Tropospheric Ozone Concentration Using a Wrapper Method
(Taylor & Francis Ltd, 2011) Sakar, C. Okan; Demir, Goksel; Kursun, Olcay; Ozdemir, Huseyin; Altay, Gokmen; Yalcin, Senay
High concentrations of ozone (O-3) in the lower troposphere increase global warming, and thus affect climatic conditions and human health. Especially in metropolitan cities like Istanbul, ozone level approximates to security levels that may threaten human health. Therefore, there are many research efforts on building accurate ozone prediction models to develop public warning strategies. The goal of this study is to construct a tropospheric (ground) ozone prediction model and analyze the effectiveness of air pollutant and meteorological variables in ozone prediction using artificial neural networks (ANNs). The air pollutant and meteorological variables used in ANN modeling are taken from monitoring stations located in Istanbul. The effectiveness of each input feature is determined by using backward elimination method which utilizes the constructed ANN model as an evaluation function. The obtained results point out that outdoor temperature (OT) and solar irradiation (Si) are the most important input features of meteorological variables, and total hydrocarbons (THC), nitrogen dioxide (NO2) and nitric oxide (NO) are those of air pollutant variables. The subset of parameters found by backward elimination feature selection method that provides the maximum prediction accuracy is obtained with six input features which are OT, SI, NO2, THC, NO, and sulfur dioxide (SO2) for both validation and test sets.
Production and Marketing Structure of Large Scale Forestry Products Industry Enterprises in Turkey
(2011) Aksu, B.; Hüseyin Koç, K.; Kurtoǧlu, A.
In Turkey, a country with 21.2 million ha of forest land, it is evident that the processed forest products have not been able to be developed to realize their potential with regards to the exports possibilities. It is obvious that the situation is to the disadvantage of Turkey in terms of the trading equilibrium when the exports and imports figures are examined. According to the results of the research carried out locally with respect to the Turkish Forest Products Industry, the emphasized problems emerge as the misapplication of incentives, the disability to catch up with the technological innovations, problems regarding raw material quality, undercapitalization, lack of qualified personnel, etc. By the help of this study which had been planned to cover the whole Turkish Forest Products Industry; the target is to reveal the structural situations of the large scale businesses in Turkey in the first few years of the 20th century, where modern management principles are assumed to be applied. The research had been finalized with the comments made upon the results of the questionnaires gathered through mostly faceto-face interviews with 415 large scale forest product firms where it was assumed that contemporary management principles and technological developments were applied relatively easier. As the questionnaire study was applied by the researchers themselves directly, it was also supported through observations. © 2011 Academic Journals.
Osmanlı İmparatorluğu’ndan Cumhuriyet’e geçişte büyük toprak sahiplerinin sınıfsal rolü ve dönüşümü
(2012) Önal, Nevzat Evrim
The prominent factor in the economic changes that happened in the last century of the Ottoman Empire is deeper integration to the capitalist world economy. From 19th Century, the intensifying trade relationships formed the first step, after which railroad concessions and external borrowing deepened the process. By the end of the century, different parts of the Empire, mainly trading ports and their hinterlands were unequally integrated to the world economy. On the other hand, by the beginning of the 19th century, the tensions created by class contradictions within the Empire could no longer be subdued. The most prominent among these tensions was the one between the provincial elite and the Ottoman rule. This tension, which was recognized regally by the signing of Sened-i İttifak between Ottoman Sultan and the prominent provincial elite (Ayan), resulted in ever-growing material gains for the provincial elite. Administrative transformations like the localization of land tenure system with Ottoman Reform (Tanzimat) and the recognition of private land ownership with Land Code dated 1858 all provided a relative autonomy from Sultan's authority for the rural elite and created opportunities for primitive accumulation. The provincial elite, who found new opportunities for material gain as the Ottoman rule failed transformed into a social stratum that contained large landowners, land tenure collectors, agricultural traders and usurers. In many cases, these roles were joined in single individuals. This class structure became the material base for the new rule, and therefore the bourgeoisie of the Turkish Republic. In this context, there is a strong continuity between the provincial elite of the Ottoman Empire and the large landowners of the Turkish Republic. This article focuses on the social role played by, and the transformation in accordance to that role of Turkish large landowners. From this ground, it will try to reach conclusions about the class features and behavior patterns peculiar to the bourgeoisie of Turkey.
The Marketization of Higher Education in Turkey (2002-2011)
(Palgrave, 2012) Onal, Nevzat Evrim
Assignment of Contract under the General Provisions of the Turkish Code of Obligations
(2013) Canarslan, Gökçe
An assignment of contract is an agreement concluded between the assignee, the assignor and the remaining party to the contract where all rights and obligations are transferred to the assignee together with the capacity as a party to the contract. An assignment of contract which is a tripartite, sui generis agreement was prescribed for certain types of contracts in the Code of Obligations (Code No. 818) like many other legal systems, nevertheless it was not included in the general provisions of the Code. Article 205 of the New Turkish Code of Obligations (Code No. 6098) introduced the assignment of contract as a general rule and thereby intended to overcome the shortcomings of novation (novatio in Roman Law), assignment of a claim or assignment of a debt all of which were applied in lieu of assignment of contract.
Current State and Future of Shipping and Logistics
(Elsevier Science Bv, 2013) Tuna, Okan; Duru, Okan
A New Simulation Modelling Approach to Continuous Berth Allocation
(Taylor & Francis Ltd, 2013) Esmer, Soner; Yildiz, Gokalp; Tuna, Okan
Within the international supply chain and logistics system, ports are an important ring of the basic transport activities. Thus, any shortage in or lack of well-planned orders encountered in the port operation processes is most likely to affect the whole logistic system, which eventually will cause undesirable delays in deliveries. This study aims at developing a simulation modelling approach to continuous berth allocation in Port of Izmir Alsancak, which has continuous quayside with two main wharfs perpendicular to each other. The simulation models which serve to evaluate the proposed modelling approach have been developed in ARENA 10.0 Simulation Software. The results of the conducted computational experiments showed that the proposed modelling approach provides more accurate and realistic estimates of performance measures, such as average berth utilisation, average ship waiting time in a queue, and the average number of ships in queuing up to get container terminals.
Greening Logistics Centers: The Evolution of Industrial Buying Criteria Towards Green
(Elsevier Science Bv, 2013) Altuntas, Ceren; Tuna, Okan; Altuntaa, Ceren
The rapidly globalizing world trade requires longer supply chains with higher attention on the environmental effects of logistics activities. Latest international conventions related with environmental regulations reinforce governments and corporations to adhere to environmental protection precautions. An effort to decrease the negative environmental effects of logistics activity is the geographical concentration of logistics companies which are called logistics centers. This study aims to provide a green industrial service buying approach for the industrial customers of logistics centers. The study combines green purchasing literature with previousely developed environmental performance indicators (EPIs) and develops a green industrial buying model for logistics centers. The model provides a framework for potential residents of a logistics center and supports their industrial buying processes. The model also serves as an input for green industrial service design in a logistics center.
Supplier’s Multiple-Bidding Strategy for the Reverse Auction in The Turkish Public Procurement Law Taking into Account Also Non-Price Attributes Together with the Price
(2014) Özçakar, Necdet; Yurdakul, Halim
Türk Kamu İhale Kanununda "Fiyat ile birlikte fiyat dışı unsurların da dikkate alındığı ihale" olarak anılan tür, devlete ait satın almalarda özellikle de yüksek değerde mühendislik sistem veya projelerin alımında kullanılmaktadır. Satın alan tarafından kapalı teklif usulü ihaleye katılabilmesi için ön elemeye tabi tutulan tedarikçiyi iki büyük zorluk beklemektedir. Bunlardan biri, idare tarafından esasları ihale dokümanında belirlenen fiyat ve fiyat dışı unsurlar için teklif verme stratejisini oluşturmak, diğeri ise bu teklifin kazanan teklif olması için satın alan tarafından, tanımı Türk Kamu İhale Kanununda yapılmış olan "ekonomik açıdan en avantajlı teklif" seçilmesidir. Bu çalışmada, idare tarafından açıklanan unsurlardaki parametreleri hedefler olarak alıp tedarikçinin kendi kısıtları doğrultusunda bu hedeflere ulaşmayı amaçlayan bir çözüm modeli olarak Hedef Programlama kullanılmış ve bir örnek çözümle tekliflerin nasıl oluşturulacağı gösterilmiştir.
The Effects of Burnout on Organizational Commitment in Logistics Sector
(2014) Dursun, Tolga; Yener, Dursun; Oskaybaş, Kader
Burnout is a psychological syndrome that reduces people's motivation, job satisfaction and organizational commitment. People whose jobs are related with human interaction are usually exposed to burnout. In the literature, three dimensions of burnout were defined as emotional exhaustion, depersonalization and reduced personal accomplishment. In this study antecedents (cynicism, role ambiguity, role conflict and organizational justice) and consequences (job satisfaction, organizational commitment) of burnout were determined in logistics sector which has never been analyzed before in Turkey. Sample size of the study was 420 and judgment sampling method was used. As a result, it was found that antecedents of burnout except organizational justice are positively correlated with burnout factors, and burnout is negatively correlated with its consequences.
Türk Kamu ihale kanununda fiyat ile birlikte fiyat dışı unsurların da dikkate alındığı ihale ve kazanan teklif
(2014) Özçakar, Necdet; Yurdakul, Halim
Türk Kamu İhale Kanununda Fiyat ile birlikte fiyat dışı unsurların da dikkate alındığı ihale olarak anılan türdevlete ait satın almalarda özellikle de yüksek değerde mühendislik sistem veya projelerin alımındakullanılmaktadır. Bu ihale türünün hem tedarikçi hem de satın alan idarelere sayısız fayda sağlamasına rağmenuygulama esaslarının çok net olarak ortaya konmaması ve bunu yapmak üzere satın alan idarelerinyetkilendirilmesi yüzünden nadiren kullanıldığı görülmektedir. Satın alan idareler için bu tür ihalelerdeki ensorunlu husus, bir yandan fiyat dışı unsurlar için teklif verme esaslarını oluştururken diğer yandan da Türk Kamuİhale Kanununda tanımlanan ekonomik açıdan en avantajlı teklifi seçmektir. Bu çalışma, her iki sorunu daçözmede satın alan idarelere yardımcı olmak ve bu sayede bu tür ihalelerin yaygınlaşmasını sağlamak amacındadır.
Religiosity as a Factor That Affects Consumer Ethnocentrism
(2014) Yener, Dursun
Tüketici etnosentrizmi tüketicilerin satın alma kararları üzerinde etkiye sahip olan önemli bir faktördür. Kendi ülkesine ait ürünlere karşı satın alma eğilimi gösteren tüketicilerin etnosentrizm eğilimleri yüksektir. Tüketicilerin bazılarının neden yüksek etnosentrizm eğilimine sahip olduğu birçok çalışmaya konu olmuştur. Öte yandan etnosentrizm ile ilişki olan birçok unsur bulunmaktadır. Dindarlıkta etnosentrizmi etkilemektedir. Dindarlık, Allport tarafından içsel ve dışsal olmak üzere iki boyut olarak tanımlanmıştır. Araştırmanın örnek kütlesi 257 kişiden oluşmaktadır. Katılımcıların tamamı 18 yaşından büyüktür ve İstanbul’da ikamet etmektedir. Yapılan analizler tüketici etnosentrizminin, içsel ve dışsal dindarlık faktörlerinden pozitif olarak etkilendiğini göstermektedir. Ayrıca çeşitli sosyo-demografik faktörlerin de hem dindarlık hem de tüketici etnosentrizmi üzerinde etkileri belirlenmiştir.
The Effect of Religiosity on Product Involvement in a Muslim Society
(2014) Yener, Dursun
Religion has an important place in social life. It does not only affect the structure of society by shaping behavior and attitudes of people but also is affected from the social construct. Since religion has been perceived as a taboo subject, the number of researches about the relationship between religiosity and marketing are limited. Most of existing papers is relevant to Christianity and other religions. This study aims to present the effect of religiosity on product involvement using Allport's intrinsic/extrinsic religious orientation scale (ROS) in a Muslim sample. Three different product categories were selected (food, cosmetics and cleaning products) to analyze. Sample size of the research is 282 people which were selected by convenience sampling method. In methodology part, correlation and regression analyses and ANOVA and independent sample t-test were used. As a result, participants' level of involvement for each product group is differentiated according to their religiosity orientation. Since the scale was applied on a Muslim sample in Turkey, the study is also important..