39 sonuçlar
Arama Sonuçları
Listeleniyor 1 - 10 / 39
Yayın Cooperative strategies, achievable rates and resource allocation for OFDMA channels(Işık Üniversitesi, 2011-07-28) Bakım, İsmail Sezi; Kaya, Onur; Işık Üniversitesi, Fen Bilimleri Enstitüsü, Elektronik Mühendisliği Doktora ProgramıThe design of next generation wireless communication systems brings along new challenges, since the degrading factors such as fading and multi-user interference become harder to deal with as the number of users and the bandwidth require- ments increase. Orthogonal Frequency Division Multiple Access (OFDMA) is a multiple accessing technique which provides a solution to both of the problems above: it provides a relatively simple way of assigning available bandwidth to users, while avoiding interference; and at the same time, it converts a frequency selective fading channel, to parallel flat fading subchannels, hence reducing the effects of intersymbol interference. However, in wireless channels, what is tradi- tionally considered as interference is in fact side information, and combined with the diversity created by the orthogonal subchannels in OFDMA, this side infor»mation can be carefully taken advantage of to increase the rates achievable by the users. In our thesis, without imposing any prior constraints on subchannel allocation, we investigate cooperation strategies, achievable rates and resource allocation for OFDMA channels. We propose new cooperative encoding strategies for wireless communication net- works över OFDMA channels. We particularly focus on a two user cooperative OFDMA system, based on block Markov superposition encoding (BMSE). We obtain expressions of the resulting achievable rate regions for ali proposed coroperative encoding strategies. We show that, by allowing for re-partitioning and re-encoding of the cooperative messages across subchannels, it is possible to better exploit the diversity created by OFDMA, and higher rates can be achieved. In order to take full advantage of the diversity created by OFDMA, we then introduce a channel adaptive cooperation strategy for OFDMA, and optimize the transmit powers as a function of the channel states. We provide the optimality conditions that need to be satisfied by the powers associated with the users' codewords and derive the closed form expressions for the optimal powers.Yayın Factors affecting understanding and applications of branded housing project marketing around the İstanbul metropolitan area(Işık Üniversitesi, 2015-01-28) Polat, Selçuk; Ferman, Ali Murat; Işık Üniversitesi, Sosyal Bilimler Enstitüsü, Çağdaş İşletme Yönetimi Doktora ProgramıMarketing is a very important issue to corporate success in today’s competitive business environment. Company’s growth and success can be strongly influenced by marketing practices. Developing marketing strategies can provide significant advantages for companies over their competitors. The aim of this study is to investigate the critical factors affecting understanding and applications of ‘branded housing project marketing’ around the Istanbul metropolitan area. Branding and market positioning depend on fulfillment of certain conditions and key criterion.It is known that the following criterion- structure of companies, quality of the product, professional services, marketing and communications perspectives- both constitute important process and leverage to increase the perceived value of a product or a company in the market. It is crucial for companies to build a solid brand in today's highly-competitive markets to benefit from the brand-related advantages such as, creating overall differentiation providing costumer encouragement and maintaining overall image of high quality. Nowadays, construction companies which build branded housing projects have already established themselves as prime actors of one of the leading and most dynamic sectors of the Turkish economy.It is an observed fact that the brand- related activities are becoming of a more strategic parameter in construction industry. In relation to this fact, each and every housing project aim to be related with a unique identity and brand image. Especially in residential real estate sector, due to the high economic values involved, marketing and sales activities are classified as crucial elements of corporate conduct.Yayın Boutique pastry management as a rising services marketing practice and a comprehensive survey of boutique pastries in İstanbul(Işık Üniversitesi, 2008) Demir, Gülper; Ferman, Ali Murat; Işık Üniversitesi, Sosyal Bilimler Enstitüsü, Çağdaş İşletme Yönetimi Doktora ProgramıConsumption of food and beverages always holds a place at the top of the list when we analyze the daily habits of consumption of human beings. The different behaviors of consumers towards food and beverage products force the relevant producers to define their consumer profiles and most appropriate marketing strategies in accordance with their target group . In food industry, customization of products can also be observed in addition to the traditional massive production strategies. Therefore, the number of enterprices like boutique pastries which produce customized products that both possess an artistic value and aims complete contentment of their customers as well is increasing very rapidly day by day in Istanbul. Although boutique pastries exist in service sector, they are forced to develop marketing strategies that are specific to their need due to the several reaons such as market demands and infinite diversity of the product opportunities, which carry artistic value. With this research , certain phenomena are explored: boutique business making customization of production and adding artistic value to the products. While conducting interviews with managers of boutique pastries provided us with information about the current state of the business, the surveys enabled us to learn more about the current state of the business, the surveys enabled us to learn more about purchase behaviours. As a result of this research, the most appropriate marketing methodologies for boutique pastry businesses are defined in accordance with the analyses consumer behaviours.Yayın Ring array processing for forward-looking intravascular and intracardiac ultrasonic imaging(Işık Üniversitesi, 2010-06-08) Tekeş, Coşkun; Karaman, Mustafa; Işık Üniversitesi, Fen Bilimleri Enstitüsü, Elektronik Mühendisliği Doktora ProgramıForward-looking (FL) catheter-based imaging systems are highly desirable for guiding interventions in IVUS and ICE applications. One of the main challenges in the array based FLIVUS systems is the large channel count which results in increased system complexity. Synthetic phased array processing with reduced firing count simplifies the front-end and hence can enable 3-D real-time imaging. Recently, we have investigated dual-ring arrays suitable for IVUS and ICE imaging. In this dissertation, we present and explored two different optimized array designs based on dual circular and hexagonal rings that are suitable for synthetic phased array processing with reduced number of firings. We used simulated annealing to optimize the wideband PSF of the array system. The optimal firing set from different Tx-Rx elements eliminates most of the redundant spatial frequencies in the coarray and produces low side lobes and number of firings. The optimization procedure starts with the calculated wideband PSF of the full set coarray including all Tx-Rx firing combinations. In every iteration step, a predefined coarray with only one element change is compared with the previous set in terms of cost function. For the two designs, we obtained optimal reduced set by minimizing both the peak side lobe level and the integrated side lobe energy. For two test cases, we obtained reduced sets of 512 and 256 coarray elements, and constructed 2-D PSFs. The simulation results show that the optimized dual circular and hexagonal ring arrays provide up to 10-dB and 5-dB improvements, respectively, in peak near side lobe level with no widening in main lobe width. Our test results show that the side lobe levels of the dual circular and hexagonal arrays can be remarkably and controllably reduced by using simulated annealing optimization, and the resulting optimal array designs can meet the resolution and speed requirements of 3-D real time IVUS and ICE imaging.Yayın 21. yüzyılda elektronik sanat ve yeni yönelimler(Işık Üniversitesi, 2017-06-05) Tuğal, Sibel; Akdeniz, Halil; Öndin, Nilüfer; Işık Üniversitesi, Sosyal Bilimler Enstitüsü, Sanat Bilimi Doktora Programıİnsan düşüncesi ve yaşam biçimleri sürekli olarak değişmektedir . İnsanlık tarihi boyunca akıl yoluyla gelişen bilim teknolojiyi doğurmuştur. 20.yüzyılın ikinci yarısından itibaren elektronik teknolojisi ve dijital teknolojik yapılarla karşılaşan insan, yeni teknolojiyi sanat pratiklerinde deneyimleyerek kendine yeni bir yol aramıştır. Teknolojinin toplumu etkileme gücüne karşın sanatın özgün niteliği ve sanatçıların hayal edebilme, sezgisellik, dönüştürme ve kurgulama güçleri bu etkileri kendine has bir Şekilde değerlendirmiş ve ait olduğu çağın olanaklarını kullanarak biçimlendirmiştir. 21.yüzyılla birlikte her alana nüfuz eden elektronik, bilgisayar ve dijital teknolojiler sebebi ile sanat ve sanatçılar teknolojiyle daha yakın ilişki kurmaya yönelmişlerdir. Sanatın üretim biçimi, sanat pratikleri ve sanatçı kimliği dijital teknolojilerdeki gelişmelerden ve kurgulanmakta olan yeni yapılanmadan etkilenmektedir. İnsanın özgür aklı ve hayal gücü ile geliştirilen sanatın elektronik teknolojisi ile birlikte geçirdiği dönüşüm incelenerek, giderek teknolojiye bağımlı olmaya başladığı düşünülen sanatın ve sanatçının aslında teknolojiyi sadece bir araç olarak kullandığı gerçeği ile karşılaşılmaktadır. Sanatçı ve sanatçının ortaya koyacağı sanat pratikleri aklın ve hayal gücünün özgür kurgularıdır. 21.yüzyılda elektronik teknolojisi temelli elektronik sanatın her alanda öncü rol oynayacağı öngörülmektedir. Teknoloji giderek daha baskın bir ortam yaratsa bile sanatın ve sanatçının özündeki yaratıcılık, duyarlılık ve hayal gücü her türlü yenilenmeyi sanatta kullanarak farklı sanat biçimlerine dönüştürmeye devam edecektir.Yayın Dynamics of designing and implementing effective change : an empirical evaluation of perception of general managers of leading companies in Turkey(Işık Üniversitesi, 2013-02-08) Tatlı, Serhat Zafer; Ferman, Ali Murat; Işık Üniversitesi, Sosyal Bilimler Enstitüsü, Çağdaş İşletme Yönetimi Doktora ProgramıIn today's business environment, it is a matter of fact that change is almost inevitable. Once change is taken into consideration, the neccessity to manage it emerges as a crucial function of management teams. Ignoring the importance of change can create catastrophic consequences for organizations. Because of this, many organizations attempted to change but unfortunately, literature exhibits that they end up with 70% failure rates in reaching desired levels. This research intends to contribute to the change management literature in two main ways. One is to reveal all factors related to success or failure in literature of change management, and second is to create a model with the key factors of change management. It is found out that literature of change management reveals 24 factors to be taken into account. All of these factors are taken into research through a three-step data collection process and the new model for change is constructed by five key variables of interest, that are namely, Leadership Quality, Managerial Quality, Motivation, User Participation, and Effective Change. The final questionnaire, after a refinement process via two pilot tests, is sent to CEOs or General Managers of Capital 500 listed companies. 190 respondents fill in the questionnaire, reaching to a 38% response rate among the population. After applying correlational, regression and mediational analyses, results show that except motivation, all other key factors of interest proved to have significant effects on success in change management. Finally, a new model for change, that is subject to a comprehensive quantitative analysis, is contributed to the literature of change management.Yayın The advertiser's perspective on advertising agency-client relationships: A survey of leading advertisers in Turkey(Işık Üniversitesi, 2006) Gülsoy, Tanses Yasemin; Akgüngör, Emine Sedef; Işık Üniversitesi, Sosyal Bilimler Enstitüsü, Çağdaş İşletme Yönetimi Doktora ProgramıThis dissertation focuses on the relationship between advertisers and their advertising agencies, in an effort to understand what drives advertiser's satisfaction in this relationship which can have considerable impact on the business success of both parties. The research develops a model of relationship satisfaction positioned within the conceptual framework of Wackman, Salmon & Salmon (1986/87). This conceptual framework has been extended with additional variables to account for the complexities of the agency-client relationship in the Turkish advertising industry today. A survey of Turkey's largest advertisers was conducted, using the face-to-face interview method. Factor analysis and regression analysis (of factor-scores) were then used to test the proposed framework. All of the dimensions of the model were found to significantly influence the advertiser's satisfaction with the agency. The results suggest that advertisers principally value the agency's creativity and the relationship with the agency. Compatibility, agency's costconsciousness, service breadth, leadership capability, and perceived contribution to advertiser's sales, market share, and brand targets were also found to be important for satisfaction. Other significant predictors are people-related attributes, strategic input, trust, cooperativeness, and prestige and full-service capability. The empirical findings are consistent with the theory and confirm the importance of relationship attributes in advertiser's satisfaction. None of the control variables was found to be significantly associated with satisfaction. The findings contribute to research concerning relationship marketing and have managerial implications.Yayın Competitiveness of professional business services: Case of Turkish advertising agencies(Işık Üniversitesi, 2008) Şahin, Çiğdem; Ansal, Hacer; Işık Üniversitesi, Sosyal Bilimler Enstitüsü, Çağdaş İşletme Yönetimi Doktora ProgramıThis study seeks to examine the extent to which internal factors affect the competitiveness of professional service firms. A case of Turkish advertising agencies is selected because of advertising industry's highly knowledge and skill intensive characteristics and the increased competition among the firms in recent years. In addition to resources, organizational and managerial capalities and the knowledge of the firms will be investigated to understand the degree of their effects on the process of their competitiveness. By conducting a case study methodology , a comparison among three multinational and three national agencies that have superior , moderate and less satisfying performances is used to explain the relationship between the sources of competitiveness and firm performance.Yayın Türk sinemasında iç göç filmlerinde birey ve mekan algısı (1960-2009)(Işık Üniversitesi, 2017-12-11) Çelik, Melek Feride; İslimyeli, Balkan Naci; Işık Üniversitesi, Sosyal Bilimler Enstitüsü, Sanat Bilimi Doktora ProgramıSinema bir eğlence sanatı olmasına rağmen, yaratıcı sinema ile birlikte dünyadaki suçlara, gerçeklere yansız bir gözle ve en ahlaki boyutta bakmaya çalışır. 1960 yılının sonlarından itibaren tüm dünyada ve Türkiye’de görülen siyasi hareketlenmeye de sinema yine aynı gerçekçilikle bakmaya devam eder. Ülkemizde 1960’lı yıllarda başlayan en dikkat çekici toplumsal değişim hareketi olan göç, Türk sinemasını da etkiler. Bu örnekler ile küçük toplumsal detayları, mekanların farklılaşmasını, kitle beklentilerini ve değişimini okuyabilmek mümkündür. Göç olgusunu ele alan filmler 1960 yılından başlayarak onar yıllık dönemlerde incelendiğinde, göç edilen mekan ve bireylerin durumu, mekanların birey üzerinde etkilerinin filmlere yansıdığı izlenir. Her on yıllık dilimlerde ekonomik, politik ve kültürel değişkenlerle birlikte göçün etkileri de farklılaşır, göç edilen şehir, mekan ve eşyalar da değişime uğrar. Bu tez çalışmasında göç sorunsalı; yukarıda sayılan nedenler çerçevesinde, filmlerde yer alan mekan, eşyalar ile karakterlerin ilişkilerinin, yönetmenlerin izleyiciye aktarış biçimlerine nasıl yansıdığına tanıklık edilerek incelendi. Filmlerin analizinde sosyolojik araştırma yöntemi olan temellendirilmiş kuram yöntemi kullanıldı. Yöntem için gerekli olan filmlerin değişik dönemlere ait olmasının yanı sıra, farklı yönetmenler seçilerek özgün bakış açıları yakalanması hedeflendi. Filmlerin mekan görsellerinin çözümlenmesinde Henri Lefebvre’nin mekanın üretimi, şehir hakkı ve modern dünyada gündelik hayat kuramlarından faydalanıldı. Çalışmanın sonunda Türk sinemasında göç edilen mekanlardaki değişim ve bu değişimin birey üzerine yansımaları değerlendirilip, yorumlandı. Böylece günümüzde de halen artarak devam eden, uluslararası bir boyuta gelmiş olan göç olgusuna sinema ile yeniden bakma ve düşünme fırsatı yaratılması hedeflenmektedir.Yayın Examination of the relationship between attitude and perceived usability of software in a context-driven specific scenario(Işık Üniversitesi, 2008) Yörük, Alp; Ferman, Ali Murat; Işık Üniversitesi, Sosyal Bilimler Enstitüsü, Çağdaş İşletme Yönetimi Doktora ProgramıLiterature regarding human and computer interaction is enormous in size. Since computers have strated to play an important role in our everyday life, researchers have focused om improving the interaction between these two entities. The usability of computer & software systems has been the main area of interest . Various techniques have been developed to measure usability. Some researchers have focused on objective usability whereas some have focused on the psychological aspect by examining subjective usability. When the objective is to examine a potential set of users' perceived usability, the context dependent nature of this specific literature even added to the difficulties. This research supplies an in-depth view of usability and computer attitude literatures, and offers computer attitude as an important variable which impacts perceived usability. A field study has been conducted in a population of 26 universities' Students in Istanbul to test the model. The research finding indicate that computer attitude is an important variable that does have a significant effect on perceived usability.
