City and Regional Planning / Şehir ve Bölge Planlama

Permanent URI for this collectionhttps://hdl.handle.net/11147/4274

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Now showing 1 - 7 of 7
  • Article
    Citation - WoS: 18
    Citation - Scopus: 19
    A Suppressed Demand Analysis Method of the Transportation Disadvantaged in Policy Making
    (Taylor and Francis Ltd., 2009) Duvarcı, Yavuz; Mizokami, Shoshi
    This paper proposes a method for estimating transportation supply requirements when the suppressed demand of the transportation disadvantaged (TD) can be calculated and added to existing demand for travel. The underlying assumption is that the travel conditions of these TD groups must be equal to the 'conventional' demand, known as 'full release'. Utilising the modelling approach for TD, suppressed demand analysis, diagnosis of difficulties and equity between conventional and disadvantaged groups were realised, while elaborating special cases for the most vulnerable TD groups (such as elderly and disabled persons) and simultaneously identifying areas of difficulty. From the early virtual results, it is concluded that, for the full release of suppressed trips (only a 5% increase), policy makers must be ready to face some financial burdens, requiring coordination of effort to both standardise these TD groups and reduce the costs incurred by operators.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 7
    An Entropy-Based Analysis of Lane Changing Behavior: An Interactive Approach
    (Taylor and Francis Ltd., 2017) Koşun, Çağlar; Özdemir, Serhan
    Objectives: As a novelty, this article proposes the nonadditive entropy framework for the description of driver behaviors during lane changing. The authors also state that this entropy framework governs the lane changing behavior in traffic flow in accordance with the long-range vehicular interactions and traffic safety. Methods: The nonadditive entropy framework is the new generalized theory of thermostatistical mechanics. Vehicular interactions during lane changing are considered within this framework. The interactive approach for the lane changing behavior of the drivers is presented in the traffic flow scenarios presented in the article. According to the traffic flow scenarios, 4 categories of traffic flow and driver behaviors are obtained. Through the scenarios, comparative analyses of nonadditive and additive entropy domains are also provided. Results: Two quadrants of the categories belong to the nonadditive entropy; the rest are involved in the additive entropy domain. Driving behaviors are extracted and the scenarios depict that nonadditivity matches safe driving well, whereas additivity corresponds to unsafe driving. Furthermore, the cooperative traffic system is considered in nonadditivity where the long-range interactions are present. However, the uncooperative traffic system falls into the additivity domain. The analyses also state that there would be possible traffic flow transitions among the quadrants. This article shows that lane changing behavior could be generalized as nonadditive, with additivity as a special case, based on the given traffic conditions. Conclusions: The nearest and close neighbor models are well within the conventional additive entropy framework. In this article, both the long-range vehicular interactions and safe driving behavior in traffic are handled in the nonadditive entropy domain. It is also inferred that the Tsallis entropy region would correspond to mandatory lane changing behavior, whereas additive and either the extensive or nonextensive entropy region would match discretionary lane changing behavior. This article states that driver behaviors would be in the nonadditive entropy domain to provide a safe traffic stream and hence with vehicle accident prevention in mind.
  • Article
    Citation - WoS: 10
    Citation - Scopus: 10
    Determinants of Co-Movement and of Lead and Lag Behavior of Business Cycles in the Eurozone
    (Taylor and Francis Ltd., 2017) Duran, Hasan Engin; Ferreira-Lopes, Alexandra
    In this paper we study business cycle correlations in the Eurozone and its determinants. Additionally, we also analyze the determinants of the lead and lag behavior of business cycles in the Eurozone. We explore the relevance, in the Eurozone context, using GDP and employment as the business cycle measures, of the determinants of business cycle synchronization identified in the literature, namely bilateral trade intensity, dissimilarity of labor market rigidity, dissimilarity in industrial structures, financial openness, and foreign direct investment relations. We estimate a simultaneous 4-equations model by Ordinary Least Squares (OLS) and three-stage least square to investigate empirically the above-mentioned determinants of business cycle correlation. Bilateral trade relations present a positive influence on business cycle correlations, while the dissimilarity of labor market rigidity presents a negative influence. The rest of the above-mentioned variables are non-significant. These results are robust to the use of the Hodrick–Prescott-filter and first differences as the de-trending methods, as well as the use of GDP as the business cycle measure, excluding the financial crisis years (2008 and 2009). Results for employment as the business cycle measure are in contrast with the previous ones, and found industrial dissimilarity to be the relevant variable to determine business cycles synchronization. In what concerns the determinants of the lead and lag behavior, results show that the member states of the Eurozone that usually lead the cycle are the ones that are wealthier, with strict employment legislation, more specialized in construction and finance sectors, and more prone to international capital movements. Differences in the determinants between contemporaneous business cycles and lead and lag behavior of business cycles are especially important for policy-makers in the Eurozone to know about, in particular if asymmetric shocks between countries are set in place.
  • Article
    Citation - WoS: 13
    Citation - Scopus: 12
    The Role of Government Policies and Strategies Behind the Shrinking Urban Core in an Expanding City Region: The Case of Izmir
    (Taylor and Francis Ltd., 2014) Özatagan, Güldem; Eraydın, Ayda
    Over the last few decades, the term urban shrinkage has come to be accepted as a valid concept in international academic circles, and has gradually gained importance, with its causes the subject of well-documented discussion. While previous discussions of urban shrinkage have directed attention to cities shrinking as a whole, recent research started to recognize the case of shrinkage in growing cities and regions. As such, recent discussions of urban shrinkage indicate that patterns of shrinkage vary considerably from city to city, and from sub-region to sub-region, with the importance of local dynamics in responding to changing economic pressures given much consideration. Recent studies have tended to disregard the role of government policies and strategies put in place to facilitate the adaptation of the urban economies to the new conditions. Taking Izmir as an example, being a fast-growing metropolitan region in Turkey, this paper presents evidence of government policies and strategies aimed at enhancing the development of peripheral areas that have led to shrinkage of the metropolitan core. This paper focuses on this experience and discusses its implications.
  • Article
    Citation - WoS: 9
    Citation - Scopus: 10
    Modelling Trip Distribution With Fuzzy and Genetic Fuzzy Systems
    (Taylor and Francis Ltd., 2013) Kompil, Mert; Çelik, Hüseyin Murat
    This paper explores the potential capabilities of fuzzy and genetic fuzzy system approaches in urban trip distribution modelling with some new features. First, a simple fuzzy rule-based system (FRBS) and a novel genetic fuzzy rule-based system [GFRBS: a fuzzy system improved by a knowledge base learning process with genetic algorithms (GAs)] are designed to model intra-city passenger flows for Istanbul. Subsequently, their accuracy, applicability and generalizability characteristics are evaluated against the well-known gravity- and neural network (NN)-based trip distribution models. The overall results show that: traditional doubly constrained gravity models are still simple and efficient; NNs may not show expected performance when they are forced to satisfy trip constraints; simply-designed FRBSs, learning from observations and expertise, are both efficient and interpretable even if the data are large and noisy; and use of GAs in fuzzy rule-based learning considerably increases modelling performance, although it brings additional computation cost.
  • Article
    Citation - WoS: 6
    Citation - Scopus: 7
    Determination of Optimum Environmental Conservation: Using Multi-Criteria Decision-Making Techniques
    (Taylor and Francis Ltd., 2011) Çelik, Hüseyin Murat; Türk, Ersin
    The type and degree of conservation areas in Turkey legally dictate the kind of land uses that can and cannot take place in a conservation area. Thus, the conservation scheme is one of the most important criteria in designing an urban land-use plan. The aim of this study is to analyse the effects of various conservation decisions on land-use allocation holding everything else constant. This study uses a land-allocation mathematical programme formulated by Hanink and Cromley [(1998) Land-use allocation in the absence of complete market values, Journal of Regional Science, 38, pp. 465-480] that integrates the geographical information systems with a generalized assignment problem to determine an optimum level of conservation scheme in Cesme/Izmir, a coastal resort in Turkey. The findings state that the proposed technique is indeed very useful and promising to answer diversified practical issues on a more rational basis.
  • Article
    Citation - WoS: 35
    Citation - Scopus: 39
    Dynamics of Value Chain Governance: Increasing Supplier Competence and Changing Power Relations in the Periphery of Automotive Production—evidence From Bursa, Turkey
    (Taylor and Francis Ltd., 2011) Özatağan, Güldem
    Adopting a global value chain (GVC) approach, this paper focuses on the ways in which global automotive transnational corporations coordinate their value chains with suppliers in the periphery of automotive production. In particular, it directs attention to particular forms of chain relations established by lead firms with suppliers in Turkey and the ways in which these chains are coordinated. Findings indicate that as component suppliers in the periphery of automotive production, such as those in Bursa, have gained the competencies not only to manufacture to the cost, quality and flexibility specifications required by their customers but also of design and product development, lead firms in the automotive industry have turned to modular value chains, where competent suppliers provide a range of services with less dependence on their customers, as a way of sourcing from these suppliers. I use this evidence to argue that GVC governance is dynamic and suppliers in the periphery have some room for breaking power asymmetries associated with specific modes of governance in GVCs.