A spanning tree approach to the absolute p-center problem

Cataloged from PDF version of article.We consider the absolute p-center problem on a general network and propose a spanning tree approach which is motivated by the fact that the problem is NP-hard on general networks but solvable in polynomial time on trees. We first prove that every connected network possesses a spanning tree whose p-center solution is also a solution for the network under consideration. Then we propose two classes of spanning trees that are shortest path trees rooted at certain points of the network. We give an experimental study, based on 1440 instances, to test how often these classes of trees include an optimizing tree. We report our computational results on the performance of both types of trees. © 1999 Elsevier Science Ltd. All rights reserved

On the single assignment p-Hub center problem

Cataloged from PDF version of article.We study the computational aspects of the single-assignment p-hub center problem on the basis of a basic model and a new model. The new model's performance is substantially better in CPU time than different linearizations of the basic model. We also prove the NP-Hardness of the problem. (C) 2000 Elsevier Science B.V. All rights reserved

The latest arrival hub location problem for cargo delivery systems with stopovers

Cataloged from PDF version of article.In this paper, we concentrate on the service structure of ground-transportation based cargo delivery companies. The transient times that arise from nonsimultaneous arrivals at hubs (typically spent for unloading, loading, and sorting operations) can constitute a significant portion of the total delivery time for cargo delivery systems. The latest arrival hub location problem is a new minimax model that focuses on the minimization of the arrival time of the last item to arrive, taking into account journey times as well as the transient times at hubs. We first focus on a typical cargo delivery firm operating in Turkey and observe that stopovers are essential components of a ground-based cargo delivery system. The existing formulations of the hub location problem in the literature do not allow stopovers since they assume direct connections between demand centers and hubs. In this paper, we propose a generic mathematical model, which allows stopovers for the latest arrival hub location problem. We improve the model using valid inequalities and lifting. We present computational results using data from the US and Turkey. 2007 Elsevier Ltd. All rights reserved

Compromising system and user interests in shelter location and evacuation planning

Cataloged from PDF version of article.Traffic management during an evacuation and the decision of where to locate the shelters are of critical importance to the performance of an evacuation plan. From the evacuation management authority’s point of view, the desirable goal is to minimize the total evacuation time by computing a system optimum (SO). However, evacuees may not be willing to take long routes enforced on them by a SO solution; but they may consent to taking routes with lengths not longer than the shortest path to the nearest shelter site by more than a tolerable factor. We develop a model that optimally locates shelters and assigns evacuees to the nearest shelter sites by assigning them to shortest paths, shortest and nearest with a given degree of tolerance, so that the total evacuation time is minimized. As the travel time on a road segment is often modeled as a nonlinear function of the flow on the segment, the resulting model is a nonlinear mixed integer programming model. We develop a solution method that can handle practical size problems using second order cone programming techniques. Using our model, we investigate the importance of the number and locations of shelter sites and the trade-off between efficiency and fairness. 2014 Elsevier Ltd. All rights reserved

Authoritarian Neoliberalism and Democratic Backsliding in Turkey: Beyond the Narratives of Progress

Unpacking the core themes that are discussed in this collection, this article both offers a research agenda to re-analyse Turkey’s ‘authoritarian turn’ and mounts a methodological challenge to the conceptual frameworks that reinforce a strict analytical separation between the ‘economic’ and the ‘political’ factors. The paper problematises the temporal break in scholarly analyses of the AKP period and rejects the argument that the party’s methods of governance have shifted from an earlier ‘democratic’ model – defined by ‘hegemony’ – to an emergent ‘authoritarian’ one. In contrast, by retracing the mechanisms of the state-led reproduction of neoliberalism since 2003, the paper demonstrates that the party’s earlier ‘hegemonic’ activities were also shaped by authoritarian tendencies which manifested at various levels of governance

Policy-making as an emotionally-charged arena: the emotional geographies of urban cultural policy-making

© 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. Analysis of the role emotions play in a range of social processes has increased significantly, but is neglected in the context of cultural policy-making. Recent literatures in feminist and emotional geographies draw attention to how emotions are emergent in, and play a role in shaping, a broad range of social contexts and processes, while other literatures stress the need to ‘personalise’ the expert and consider the emotional aspects of planning. Inspired by these literatures we deploy the notion of ‘affective urbanism’ to study how emotions are interwoven with cultural policy spaces in the city and explore the ‘emotional regimes’ that incorporate emotions with the multi-scalar politics that is shaping urban cultural policy-making. This is undertaken through an analysis of emotions in the working lives and political contexts of cultural policy-makers in Stockholm (Sweden), Gdańsk (Poland) and Manchester (UK). Overall the paper seeks to develop a research agenda that places emotions centrally in studies of cultural policy formation and implementation

Managerial power in the German model: the case of Bertelsmann and the antecedents of neoliberalism

Our article extends the research on authoritarian neoliberalism to Germany, through a history of the Bertelsmann media corporation – sponsor and namesake of Germany’s most influential neoliberal think-tank. Our article makes three conceptual moves. Firstly, we argue that conceptualizing German neoliberalism in terms of an ‘ordoliberal paradigm’ is of limited use in explaining the rise and fall of Germany’s distinctive socio-economic model (Modell Deutschland). Instead, we locate the origins of authoritarian tendencies in the corporate power exercised by managers rather than in the power of state-backed markets imagined by ordoliberals. Secondly, we focus on the managerial innovations of Bertelsmann as a key actor enmeshed with Modell Deutschland. We show that the adaptation of business management practices of an endogenous ‘Cologne School’ empowered Bertelsmann’s postwar managers to overcome existential crises and financial constraints despite being excluded from Germany’s corporate support network. Thirdly, we argue that their further development in the 1970s also enabled Bertelsmann to curtail and circumvent the forms of labour representation associated with Modell Deutschland. Inspired by cybernetic management theories that it used to limit and control rather than revive market competition among its workforce, Bertelsmann began to act and think outside the postwar settlement between capital and labour before the settlement’s hotly-debated demise since the 1990s

Understanding Change in Romantic Relationship Expectations of International Female Students from Turkey

In the light of grounded theory, the authors explored change in romantic relationship expectations of international students. Twelve female graduate students from Turkey were interviewed and several themes were identified explaining the presence and absence of change in participants’ attitudes toward romantic relationships. The findings are discussed in relation to acculturation and direction for future research is presented