Multihop Diversity in Wideband OFDM Systems: The Impact of Spatial Reuse and Frequency Selectivity

The goal of this paper is to establish which practical routing schemes for wireless networks are most suitable for wideband systems in the power-limited regime, which is, for example, a practically relevant mode of operation for the analysis of ultrawideband (UWB) mesh networks. For this purpose, we study the tradeoff between energy efficiency and spectral efficiency (known as the power-bandwidth tradeoff) in a wideband linear multihop network in which transmissions employ orthogonal frequency-division multiplexing (OFDM) modulation and are affected by quasi-static, frequency-selective fading. Considering open-loop (fixed-rate) and closed-loop (rate-adaptive) multihop relaying techniques, we characterize the impact of routing with spatial reuse on the statistical properties of the end-to-end conditional mutual information (conditioned on the specific values of the channel fading parameters and therefore treated as a random variable) and on the energy and spectral efficiency measures of the wideband regime. Our analysis particularly deals with the convergence of these end-to-end performance measures in the case of large number of hops, i.e., the phenomenon first observed in \cite{Oyman06b} and named as ``multihop diversity''. Our results demonstrate the realizability of the multihop diversity advantages in the case of routing with spatial reuse for wideband OFDM systems under wireless channel effects such as path-loss and quasi-static frequency-selective multipath fading.Comment: 6 pages, to be published in Proc. 2008 IEEE International Symposium on Spread Spectrum Techniques and Applications (IEEE ISSSTA'08), Bologna, Ital

Interpretation of Educational Administration in the Context of Dilthey’s Hermeneutic Approach

The purpose of this study is to interpret the field of educational administration according to the philosophy of Dilthey, one of the most important representatives of the hermeneutical approach, which deals with the human being in variability, historicity. Educational administration that claims to be a science has internalized positivist approach and its methods. Dilthey has established a methodology for a new science by criticizing this approach for being insufficient in understanding the human being. Hermeneutics is defined as interpretation of knowledge and against the hegemony of scientificity imposed by positivist theory, it is a current thought which emphasizes subjectivity based on human life. Its purpose is not to deny natural sciences, but to reveal the inadequacy of reductionist approach in solving the complex nature of social life and human. In order to enable educational scientists to understand the social phenomena in an effective way, the recognition of all aspects of society will provide more productive results. So this study emphasizes the importance of the hermeneutic approach in providing an understanding that can go beyond the boundaries of natural sciences by developing alternative perspective of understanding ability in educational administration

The Professionalization of Male Circumcision in Turkey

Male circumcision is seen as a cultural and religious event and a rite of passage for boys in Turkey. It is surrounded by public rituals and as there is no equivalent rite of passage for girl children, circumcision signifies a crucial marker of not only religious but also gender differentiation between boys and girls. Circumcision is a men’s affair and performing circumcision bestows economic privilege and social status on circumcisers (sünnetçi). In this dissertation, I trace the practical and discursive changes in the experience of male circumcision from the perspectives of practitioners. I argue that while circumcision was always a men’s affair, the professionalization and medicalization of circumcision recast the traditional occupation as a site of public masculinity by positing credentials as a barrier to access. This class-based form of modern masculinity, in different historical periods, emphasize the ideals of rationality and science embedded within modern circumcision techniques. My work unravels the ties between masculinity and work by examining the power relations among different groups of male practitioners of circumcision (traditional circumcisers, health officers, and specialists) mediated by their interactions with families. The medicalization of circumcision (i.e. the introduction of new definitions, values, and knowledge into the practice) was an opportunity for each professional group (first health officers and then specialists) to claim their superiority over other groups and expand their jurisdictions. My dissertation contributes to the feminist studies focusing on the relationship between gender and (professional) work from (neo-) Weberian perspective

Cahit Arf ve lise öğrencisi

Taha Toros Arşivi, Dosya No: 357-Cahit ArfUnutma İstanbul projesi İstanbul Kalkınma Ajansı'nın 2016 yılı "Yenilikçi ve Yaratıcı İstanbul Mali Destek Programı" kapsamında desteklenmiştir. Proje No: TR10/16/YNY/010