Browsing by Subject "Internet"

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1995-2005 yılları arasında Türkiye’deki internet kafe kültürü
(Bilkent University, 2021) Dalyan, Yiğit Alp; Özata, Serdar; Özbay, Hulusi Melih; Yılmaz, Bahadır Can; Yılmaz, Çağan
Bu çalışmada 1995-2005 yılları arasında Türkiye’deki internet kafe kültürü araştırılmıştır. 1995 yılında başlayan bu kültür, birçok tartışma konusunu da beraberinde getirmiştir. Bu makalede, internet kafelerin neden sıkça ziyaret edildiği ve gençlerin sosyal yaşamlarına etkisi konu alınmıştır. Aynı zamanda internet kafelerin korsan dizi, film ve oyun sektörleri üzerindeki etkilerine ve internet kafe sektöründen insanların görüşlerine de yer verilmiştir.
Open Access
Advantage of using Web 2.0 applications in class
(ACM, 2010) Aydinol, Ayşe Begüm; Gültekin, Özgür
In this study the advantage of using Web 2.0 applications in terms of increasing student attention and enthusiasm will be emphasized by presenting the example of community service activities which were supported by the blog usage. Copyright 2010 ACM.
Open Access
AIMD-based online MPLS traffic engineering for TCP flows via distributed multi-path routing
(Springer, 2004) Alparslan O.; Akar, N.; Karasan, E.
With this paper, we propose a distributed online traffic engineering architecture for MPLS networks. In this architecture, a primary and secondary MPLS LSP are established from an ingress LSR to every other egress LSR. We propose to split the TCP traffic between the primary and secondary paths using a distributed mechanism based on ECN marking and AIMD-based rate control. Inspired by the random early detection mechanism for active queue management, we propose a random early reroute scheme to adaptively control the delay difference between the primary and secondary LSPS. Considering the adverse effect of packet reordering on TCP performance for packet-based load balancing schemes, we propose that the TCP splitting mechanism operates on a per-flow basis. Using flow-based models developed for Internet traffic and simulations, we show that flow-based distributed multi-path traffic engineering outperforms on a consistent basis the case of a single path in terms of per-flow goodputs. Due to the elimination of out-of-order packet arrivals, flow-based splitting also enhances TCP performance with respect to packet-based splitting especially for long TCP flows that are hit hard by packet reordering. We also compare and contrast two queuing architectures for differential treatment of data packets routed over primary and secondary LSPS in the MPLS data plane, namely first-in-first-out and strict priority queuing. We show through simulations that strict priority queuing is more effective and relatively more robust with respect to the changes in the traffic demand matrix than first-in-first-out queuing in the context of distributed multi-path routing.
Open Access
An analysis of strategic behavior in eBAY auctions
(World Scientific Publishing Co. Pte. Ltd., 2009) Gonzalez, R.; Hasker, K.; Sickles, R. C.
A relatively new type of panel data analysis is becoming more and more topical in the applied econometrics literature as auction mechanisms are being explored in more depth. The typical data utilized in such studies involves repeated measures of auction outcomes, where the variable of interest involves order statistics from the sample of bids from many bids on completed auctions for a particular commodity. This article presents structural estimates of bidding behavior in eBay computer monitor auctions. We exploit characteristics of such repeated measures to analyze the efficiency of private value auctions for a relatively homogeneous good, computer monitors sold on eBay. We discuss how outcomes of the auction mechanism can be analyzed and their equilibrium outcomes assessed and evaluate the consumer surplus that is generated from such auctions. Particular attention is given to the collection of the eBay data from data recovery protocols that monitor in real time and in relative detail, characteristics of a particular auction with heterogeneity controls for different types of monitors and for different reputation effects of the auctioneer. Among other findings, our results point to a rejection of the use of Jump Bidding (Avery, 1998) or "Snipe or War" bidding (Roth and Ockenfels, 2002). We also find that longer auctions only have a small effect on price and experienced auctioneers respond to this incentive. © 2009 World Scientific Publishing Company.
Open Access
ChiBE: interactive visualization and manipulation of BioPAX pathway models
(Oxford University Press, 2010-02-01) Babur, Özgün; Doğrusöz, Uğur; Demir, Emek; Sander, C.
SUMMARY: Representing models of cellular processes or pathways in a graphically rich form facilitates interpretation of biological observations and generation of new hypotheses. Solving biological problems using large pathway datasets requires software that can combine data mapping, querying and visualization as well as providing access to diverse data resources on the Internet. ChiBE is an open source software application that features user-friendly multi-view display, navigation and manipulation of pathway models in BioPAX format. Pathway views are rendered in a feature-rich format, and may be laid out and edited with state-of-the-art visualization methods, including compound or nested structures for visualizing cellular compartments and molecular complexes. Users can easily query and visualize pathways through an integrated Pathway Commons query tool and analyze molecular profiles in pathway context. AVAILABILITY: http://www.bilkent.edu.tr/%7Ebcbi/chibe.html. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
Open Access
Çok-akışlı eşler arası isteğe bağlı video sistemlerinin Markov zinciri tabanlı güvenilirlik modellemesi
(IEEE, 2008-04) Yazıcı, Mehmet Akif; Öztoprak, K.; Akar, Nail; Akar, G. B.
Çok-akışlı eşler-arası video, gelecek nesil isteğe bağlı video sistemleri için kullanılmaya aday teknolojilerdendir. Çok-akışlı video sistemlerinin sorunlarından birisi, eş dalgalanması adı verilen, eşlerin ağla olan bağlantılarının kopup düzelmesi durumudur. Eş dalgalanmasının bütün eşler-arası sistemlerde olumsuz etkileri olduğu bilinmektedir. Bu etkinin hafifletilmesi için çeşitli hata kontrollü alt-akış kodlama teknikleri önerilmiştir. Bu makalede, eş dalgalanması ve hata kontrolünün rolünü incelemek amacıyla sürekli zamanlı Markov zinciri tabanlı bir rassal model önerilmektedir. Bu model kullanılarak, hata kontrolünün rolü, gelecek nesil çok-akışlı eşler-arası isteğe bağlı video sistemlerinin tasarımında kullanılmak üzere nicel olarak ortaya konmaktadır.
Open Access
Comparative analysis of power consumption in asynchronous wavelength modular optical switching fabrics
(Elsevier, 2011-04-02) Akar, N.; Eramo, V.; Raffaelli, C.
Next-generation optical routers will be designed to support the flexibility required by Future Internet services and, at the same time, to overcome the power consumption bottleneck which appears to limit throughput scalability in today routers. A model to evaluate average power consumption in asynchronous optical switching fabrics is here presented to compare these architectures with other synchronous and asynchronous solutions. The combination of wavelength modular switching fabrics with low spatial complexity and asynchronous operation is demonstrated to be the most power-efficient solution among those considered which employ wavelength converters, through presentation and discussion of a thorough set of numerical results.
Open Access
Content-based retrieval of historical Ottoman documents stored as textual images
(IEEE, 2004) Şaykol, E.; Sinop, A. K.; Güdükbay, Uğur; Ulusoy, Özgür; Çetin, A. Enis
There is an accelerating demand to access the visual content of documents stored in historical and cultural archives. Availability of electronic imaging tools and effective image processing techniques makes it feasible to process the multimedia data in large databases. In this paper, a framework for content-based retrieval of historical documents in the Ottoman Empire archives is presented. The documents are stored as textual images, which are compressed by constructing a library of symbols occurring in a document, and the symbols in the original image are then replaced with pointers into the codebook to obtain a compressed representation of the image. The features in wavelet and spatial domain based on angular and distance span of shapes are used to extract the symbols. In order to make content-based retrieval in historical archives, a query is specified as a rectangular region in an input image and the same symbol-extraction process is applied to the query region. The queries are processed on the codebook of documents and the query images are identified in the resulting documents using the pointers in textual images. The querying process does not require decompression of images. The new content-based retrieval framework is also applicable to many other document archives using different scripts.
Open Access
Curse and internet as a means of social control
(2007) Kocaer, S.
Many innovations have come to the life of society by technology and some of these innovations have created new cultural areas. Internet has become one of these new cultural areas where cultural codes are produced and consumed. By internet, "reader forums" named social spaces are made up in the virtual newspapers. In these reader forums people address to other people that they do not know and write their own interpretations about the news and read the unknown people's interpretations and even they write responses to those unknown people. Therefore, it is very clear that these internet spaces have become social areas where cultural codes are shared and new codes are produced. It is observed that the concept of curse which has an important place in society carries on its being in these virtual areas. The word "curse" literally has religious connotations. But, does curse have other functions in society? When curses are analyzed according to the social control theory it is observed that curses have psychological and social functions in society. In this article the concept of curse will be analyzed and the function of curse in society will be discussed according to the social control theory. In addition to these, the virtual internet space, which has become a new social area during the changing and conversion period from rural to urban, will be discussed and the place of curse in this new social space will be argued out.
Open Access
Designing for web and for printed medium: a comparative study
(2001) Michalski, Jakub
A thesis comparing two methods of design; the web design and design prepared for the printed medium, covering the physical differences between the two, the methods and techniques of content presentation in both cases, as well, as the perception of the design from the reader’s point of view. Includes a case study.
Open Access
Dynamic congestion control in interconnected computer networks
(IEEE, 1988-10) Ulusoy, Özgür; Baray, Mehmet
The authors evaluate a window-based congestion control mechanism in an internetwork environment. They also propose and study two dynamic-window congestion-control algorithms. These algorithms provide further control to the window mechanism by adjusting the window size in accordance with the availability of the network resources at the destination. A comparison of dynamic algorithms with fixed window control is provided in terms of throughput and delay performance. It is shown that dynamic algorithms have considerable performance advantages over fixed-window control.
Open Access
The dynamic interaction between advertising and popular culture : a case study on Ixir TV commercials
(2006) Seçmeer, Bahar
In the scope of the thesis, the “advertising” concept--rather than its economic dimension-- is taken as a matter of culture under the form of popular culture, serving as a repository for social and cultural data. How the dynamic interaction and the mutually exclusive culture generation among advertising and popular culture takes place is examined upon the latest commercials for validity and up to datedness. Furthermore, İxir TV commercials, because of their periodical importance, rich content and popularity are chosen as the sample case for further investigations.
Open Access
Dynamics of commitment and contribution quality in collaborative communities
(IEEE, 2007-11) Schaal, Markus; Eren, Y.
It is well-known that commitment is an important ingredient for contributions of high quality. With the internet heading towards being an actionable social space, rather than a collection of web-sites, the issue of quality becomes crucial for sharing knowledge and action in collaborative scenarios. We propose a case study for the investigation of the influence of time, user feedback and interface complexity on contribution quality. We plan to exploit different online user groups across two different temporal phases for the evaluation.
Open Access
GOPred: GO molecular function prediction by combined classifiers
(2010) Saraç Ö.S.; Atalay V.; Cetin-Atalay, R.
Functional protein annotation is an important matter for in vivo and in silico biology. Several computational methods have been proposed that make use of a wide range of features such as motifs, domains, homology, structure and physicochemical properties. There is no single method that performs best in all functional classification problems because information obtained using any of these features depends on the function to be assigned to the protein. In this study, we portray a novel approach that combines different methods to better represent protein function. First, we formulated the function annotation problem as a classification problem defined on 300 different Gene Ontology (GO) terms from molecular function aspect. We presented a method to form positive and negative training examples while taking into account the directed acyclic graph (DAG) structure and evidence codes of GO. We applied three different methods and their combinations. Results show that combining different methods improves prediction accuracy in most cases. The proposed method, GOPred, is available as an online computational annotation tool (http://kinaz.fen.bilkent.edu.tr/gopred). © 2010 Saraç et al.
Open Access
How terrorists use the internet
(2021-09) Özyurt, Eylül
The advent of technology has offered various advantages to terrorist and insurgent groups as well as it has done to the states, business world, and ordinary individuals. Terrorists have been using the Internet with the purposes of propaganda; training, planning, and execution; and financing. This thesis aims to analyze how terrorists actually do use the Internet for those purposes, by which means. In that context, case studies are reviewed to explore the methods employed. Findings of this study reveal that terrorists still use the real world to carry out attacks more than they make use of the Internet for this aim. Therefore, the Internet use of terrorists has come as an adjunct to their real life activities. In that consideration, this thesis emerges as a preliminary survey trying to illustrate the link between terrorism and cybersecurity studies.
Open Access
H∞-performance analysis of robust controllers designed for AQM
(IEEE, 2003) Yan, P.; Özbay, Hitay
It has been shown that the TCP connections through the congested routers with the Active Queue Management (AQM) can be modeled as a nonlinear feedback system. In this paper, we design H∞ robust controllers for AQM based on the linearized TCP model with time delays. For the linear system model exhibiting LPV nature, we investigate the H∞-performance with respect to the uncertainty bound of RTT (round trip time). The robust controllers and the corresponding analysis of H∞-performance are validated by simulations in different scenarios.
Open Access
Impact of scalability in video transmission in promotion-capable differentiated services networks
(IEEE, 2002-09) Gürses, E.; Akar, G. B.; Akar, Nail
Transmission of high quality video over the Internet faces many challenges including unpredictable packet loss characteristics of the current Internet and the heterogeneity of receivers in terms of their bandwidth and processing capabilities. To address these challanges, we propose an architecture in this paper that is based on the temporally scalable and error resilient video coding mode of the H.263+ codec. In this architecture, the video frames will be transported over a new generation IP network that supports differentiated services (Diffserv). We also propose a novel Two Rate Three Color Promotion-Capable Marker (trTCPCM) to be used at the edge of the diffserv network. Our simulation study demonstrates that an average of 30 dB can be achieved in case of highly congested links.
Open Access
Integrative analysis of complex cancer genomics and clinical profiles using the cBioPortal
(American Association for the Advancement of Science (A A A S), 2013) Gao J.; Aksoy, B. A.; Dogrusoz, U.; Dresdner, G.; Gross, B.; Sumer, S. O.; Sun, Y.; Jacobsen, A.; Sinha, R.; Larsson, E.; Cerami, E.; Sander, C.; Schultz, N.
The cBioPortal for Cancer Genomics (http://cbioportal.org) provides a Web resource for exploring, visualizing, and analyzing multidimensional cancer genomics data. The portal reduces molecular profiling data from cancer tissues and cell lines into readily understandable genetic, epigenetic, gene expression, and proteomic events. The query interface combined with customized data storage enables researchers to interactively explore genetic alterations across samples, genes, and pathways and, when available in the underlying data, to link these to clinical outcomes. The portal provides graphical summaries of gene-level data from multiple platforms, network visualization and analysis, survival analysis, patient-centric queries, and software programmatic access. The intuitive Web interface of the portal makes complex cancer genomics profiles accessible to researchers and clinicians without requiring bioinformatics expertise, thus facilitating biological discoveries. Here, we provide a practical guide to the analysis and visualization features of the cBioPortal for Cancer Genomics. © 2013 American Association for the Advancement of Science.
Open Access
Internet and social media uses, digital divides, and digitally mediated transnationalism in forced migration: Syrians in Turkey
(Wiley-Blackwell Publishing, Inc., 2021-08-27) Jauhiainen, J. S.; Özçürümez, Saime; Tursun, Özgün
This article studied Internet and social media uses, digital divides (access, use, and impact of the Internet and social media), and digitally mediated transnationalism in forced migration with the case of Syrians in Turkey. The mixed method analysis is based on surveys with 762 respondents, 52 interviews, and participant observations among Syrians in Gaziantep, Istanbul, and Izmir provinces in Turkey. Digitally mediated transnationalism became the everyday strategy, practice, and resilience of Syrians in Turkey. The first- and second-level digital divides, that is, the differences in their access to and use of the Internet and social media diminished while many third-level digital divides (impacts) remained. Syrians in Turkey used information and communication technologies, the Internet and social media for accessing basic needs and services, to enhance their challenging psycho-social well-being, to maintain transnational bonding and bridging connections to Syria, the European Union and elsewhere, and some also to implement their mobility plans.
Open Access
İnternetin ezber bozan ortamında ve yenilikçi dijital pazarlarda rekabet hukuku eğilimleri
(Rekabet Kurumu, 2015) Gürkaynak, Gönenç; Derya, Durlu-Gürzumar
Teşebbüslerin internet ortamındaki faaliyetlerinin hızla yayılmasıyla birlikte, bu faaliyetlerde, rekabet hukuku ilke ve parametrelerini geleneksel yaklaşım yerine, daha esnek bir değerlendirmeyle ele alan uygulama yöntemlerini tercih etmenin doğru olup olmayacağı sorusunun önemi artmıştır. Bu çalışmada internet ortamı ve dijital platformların özelliklerinin neler olduğu açıklandıktan sonra Amerika Birleşik Devletleri ve Avrupa Birliği ülkelerindeki gelişmeler ışığında, şu konular incelenmiştir: (i) Özellikle Google’ın ve Apple’ın elektronik kitap uygulamaları hakkında açılan soruşturmalarda rekabet otoritelerinin benimsediği yaklaşım çerçevesinde, teşebbüslerarası anlaşmalardaki fiyat tespitleri; (ii) Google hakkında yürütülmüş olan iki soruşturma ışığında, internet ortamında oluşan pazarlarda hâkim durum ve kötüye kullanılması meselesi; (iii) Google/Motorola Mobility Inc. işlemi bağlamında, rekabet otoritelerinin, internet ortamında faaliyet gösteren teşebbüslerin birleşme-devralma işlemleri hakkındaki yaklaşımı. Çalışmanın sonuç kısmında internet ortamındaki teşebbüs faaliyetleri bakımından rekabet hukukunda gelinen nokta özetlenmiş ve olası açılımlar hakkında önerilerde bulunulmuştur