Fen Bilimleri Enstitüsü

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Maintaining Cybersecurity Awareness in Large-Scale Organizations: a Pilot Study in a Public Institution
(IGI Global, 2023) Aslan, M.; Pusatli, T.
Research was conducted to increase the awareness of employees with regard to cyber security to fill the gap in the literature where few studies on how effective the measures implemented in organizations were reported. This research uses the outcome of the phishing drills that a public institution applied to its personnel, participation of said personnel in awareness training, and the reading statistics of regularly published information security bulletins. This has been beneficial in determining the methods to increase the cyber security awareness of personnel in organizations with 1,000 or more personnel; users were considered as a whole, and not individually evaluated. Findings report that organizations can increase users' cybersecurity awareness by systematically conducting phishing exercises, providing awareness training, and regularly publishing information security bulletins. The awareness of reading bulletins rapidly increased after phishing exercises and training and decreased in the following months; however, an increase was observed in the long term. © 2023, IGI Global. All rights reserved.
Model based human face detection using skin color segmentation
(2002) Özbay, Eylem
Model Based Human Face Detection Using Skin Color Segmentation Özbay, Eylem Ms, Department of Computer Engineering Supervisor: Dr. Reza Hassanpour January 2005, 85 pages For identification of the people easiest way using the faces. However, it requires determining the location of the faces in the images. Face Identification systems are generally preceded by face segmentation systems. The main goal of thesis is locating the human faces and segmentation regions belonging to them using skin color segmentation methods and facial features such as nose, eyes, mouth etc. The segmentation results may be used as input to other related systems
Design and analysis of native XML databases in three-tier architectures
(2004) Ergen, Mehmet Tunç
XML is rapidly emerging as a standard for exchanging business data on the World Wide Web. From management systems to e-business application providers to pure development tools, XML has gone from newly underground technology to integrated component standard. It is used as the file format of choice for Web development, document interchange, and date interchange, and presents a new world of opportunities and challenges to programmers. It is predicted that by at the end of 2004, more than 75% of e-business applications will include XML regardless of which language the application has been written in. As more and more applications starts using XML there wilt be a need to efficiently handle the XML data at the back-end. The need to efficiently store and process XML documents has created the new XML supported technologies and tools. One of these tools is the Native XML Databases. It is based on document-in, document-out architecture with capabilities for storage, retrieval, querying and updating the documents. While Native XML Databases are an important new technology, they should not be used without careful analysis and consideration. In this thesis Native XML Databases are investigated and analyzed in a 3-tier architecture to gain and ensure several advantages that three-tier systems offer to application developers and information technology industry
Comparative study of human face identification methods
(2005) Karaömeroğlu, Betül
Face recognition algorithms have gained popularity in the recent years. Nowa days there are a lot of face recognition systems. However, it is known that these systems work properly in ideal environments. Behind of that, these applications provide low performance in some situations such as illumination, occlusion, different facial expression or presence of rotation and tilt conditions. In this thesis, a new approach to face recognition problem has been proposed. The presented system is a specialized version of PCA augmented with Gabor Wavelet Transform. Firstly, 2D Gabor Wavelet Transform is applied to cope with the variations due to illumination and facial expression changes; then the modified PCA approach is used for reducing a large set of correlated variables iii to a small number of uncorrelated components. The performance of the proposed algorithm is compared with the other algo rithms based on the effect of the illumination, facial expression and occluding objects such as eye glasses and facial hair
A Comparative socio-cultural and environmental study on traditional interior courtyard houses of Tripoli and Antakya
(2003) Sharif, Salem
his research focuses on traditional interior courtyard houses as one of the fundamental topologies of housing. It is an attempt to investigate the socio-cultural and environmental factors that are assumed to have an important role in shaping and configuring the interior courtyard house. The interior courtyard house has been investigated in detail within this socio-cultural framework starting from the theoretical literature and field studies. Consequently case-studies in both Tripoli (Libya) and Antakya (Turkey) are selected to examine the several concluded principles that have been driven from the theoretical reviews and applied in fieldwork. Comparing the results of both studies in interior courtyards in Tripoli and Antakya exposes differences in interior courtyard configurations due to socio-cultural context as well as environmental aspects. Interior courtyards are integral parts in creating house identity and core construction for spatial relations among other spaces of the dwelling units. While this study reveals several interesting results about effects of socio-cultural and environmental factors in the interior courtyards, it primarily discusses different methods for analyzing the interior courtyard from different perspectives. The literature review exposes several aspects concerning the interior courtyard configurations in the houses. While most researchers focus only on one specific functional or climatic topic, this thesis includes important elements from both socio- mcultural and environmental aspects; as one of the ultimate goals of this study is to produce individual identities through creative design principles for interior courtyard houses for the designers.
Design and implementation of a search engine supported bookmarking service
(2003) Dilek, Mustafa Hadi
The bookmarks are the tools used by the Web users for revisiting the Web pages that they have visited before. But, the bookmak management approaches are not sufficient yet to use efficiently most of the facilities offered by the bookmarks, especially fast access to information. In this work, & system that the Web users can easily access to their bookmarks from anywhere and any browser has been developed and implemented. This system includes a centralized server and visually rich bookmark agents which join to this server. This system has also a search engine component at the server side. So, the bookmarks of the users can be crawled and indexed regularly. This is a new approach for the classical usage of bookmarks, and with this work the bookmarks turns to shareable personal search assistants.
Developing a library for computer graphics application based on Direct X functions
(2004) Rapaka, Rajesh
The growing need for computer graphics applications demands flexible and powerful libraries. However, the available libraries are not easy - to - use software systems. The main reason is that these systems have been developed for general applications and a large number of different cases including error cases have been dealt with. My aim in this project is simplifying the use of these systems by developing a shell, which includes some library functions. These functions deal with the general cases and eliminate the need for considering them in the developed programs. Ill Some libraries were developed for "Moving in a 3D environment", "Auto texture generation", "Illumination" and "Texture blending". These libraries should reduce the strenuous manual coding and give accuracy and simplicity in debugging. Many untouched parts of OpenGL were revised and many undesired functionality were corrected
3D graphics engine design
(2004) Bal, Muammer
This thesis presents a 3D Graphics Engine design which includes geometrical methods, graphics pipeline, collision detection, animation of characters, geometric level of detail, terrain, and special effect parts. The quality and also the speed of the designed 3D Graphic Engine is very important. Because of this all methods that are used in designed 3D Graphic Engine are selected as to reach high quality and speed. Application of the designed 3D Graphic Engine shows that the Engine supports high quality and speed
Analysis of natural language sentences using natural language processing methods
(2005) Bolat, Saadettin
The aim of this study is to develop a Web-based Question Answering System, which primarily focuses on open domain fact-based short answer questions and also some definition questions. The system takes the advantage of Web which contains enormous amount of documents available online and the redundancy (multiple answer occurrences) available in the Web documents. In order to find a correct answer to a question, the first step is to determine the type of answer that the question asks for. The system analyzes and classifies the questions according to the hand-made question analysis templates. These question analysis templates are based on the question words, English grammar and some other keywords in the questions. It first creates possible sentence substrings and then search engine specific queries. To analyze the retrieved search results, the system applies a series of filters to each sentence containing the iii candidate answer and a score is given to each sentence. Among all candidate sentences, top 5 ranked sentences containing the answers are returned as possible answers. The performance of our system has been compared to the AnswerBus question answering system which is an online, publicly accessible system on the Web, and similar to our approach in several aspects. According to the evaluation results, our system appeared better than AnswerBus in terms of accuracy
Computer network simulation
(2004) Faraj, Aqeel
This thesis discusses about simulation of collision rate in Ethernet (local area network) by using CSMA/CD (carrier sense multiple access /collision detection). We try to simulate this network by introducing five different types of protocols which are Pure Aloha, Slotted Aloha, 1 -persistent, Non- persistent and P-persistent protocols. These protocols are investigated to find out which protocol has less collision rate and more data sending rate (DSR) based on some parameters such as; file size, waiting time and so on. And also the effects of the file size and the size of data packet on collision rate, data sending rate and total time have been obtained for all protocols used. m In this thesis a simulation program is used. Simulation has been implemented by using VC++ User interface, where we use Ethernet network with 10 computers connected to the same line, in order to allow the user for controlling in the parameters of network. Choosing a proper protocol is significant and has effect on the overall performance of the network [1-2]
Citation - Scopus: 4
Nonuniform Currents Flowing on a Perfectly Conducting Cylinder
(2011) Başdemir, H.D.
In this paper, we applied physical theory of diffraction (PTD) method to the perfectly electric conducting (PEC) cylinder for investigation of the scattering fields. Physical optics (PO) method was used to gain the uniform scattering field which is produced by the induced current from the incident wave on the tangential plane of the perfectly electric conducting cylinder. Nonuniform current and scattered field will be obtained by applying PTD method to the problem. As a last step of solution, nonuniform currents and nonuniform scattering fields were obtained with the assistance of the exact solution of the scattering waves from the cylinder. The scattering fields and currents are plotted numerically. © 2011 IEEE.
Winter garden design and its effects on inner place atmosphere: A case study in Ankara
(2005) Turhan, Çağla
Today, development of science and technology causes different problems. Clean energy sonrces are searched due to environmental pollution. in addition, studies on solar energy has been accelerated because today's energy resources are expensive, scarce and at the monopoly of certain countries. Therefore, different disciplines are conducting studies on solar energy. Öne of the most important problems of today is increasing number of reinforced concrete buildings and decrease in green areas because of crooked urbanization. Particularly, people living in city, yearn for narure. Winter gardens have an important place among architectural iiiisolution proposals for ali these problems. in architecture, winter garden is mentioned under several headings as "Ecological Architecture", "Benefiting from Solar Energy in Architecture', "Biological Architecture' ete. in history, greenhouse kind buildings are earliest form of winter gardens. Today, it is discovered that they have many benefits to the user. Reasons for preferring winter gardens are cultivating plants in balanced inner place climate, pleasant view and intermediate place gain. However, they also contribute to the savings of the integrated building's heating, cooling and artificial illumination costs by getting solar energy into the inner space. They have also positive effects on user's psychological and physical health due to ali these gains. A proper design of the vvinter garden is very important in terms of its efficiency. If a vvinter garden is implemented without taking required measures, it will cause damage rather than benefit to the user. Therefore, in this study, elements that effect winter garden design are analyzed. Under the light of informations obtained from ali these studies, a whıter garden, integrated to semi-detached villas in Mesa Koru housing area is criticized and analyzed and a solution proposal is developed. Then, both existing and proposed vvinter gardens are compared. Villa's situation before the integration of vvinter garden is also included into this comparison in order to highlight effects of vvinter garden's integration to the building
Citation - Scopus: 5
Investigating End User Errors in Oil and Gas Critical Control Systems
(Association for Computing Machinery, 2020) Alrawi, L.N.; Pusatli, T.
System availability and efficiency are critical in the petroleum sector as any fault affecting those systems may negatively impact operations resources, such as money, human resources and time. Therefore, it has become important to investigate the reasons for such errors. In this study, human error has been targeted since a number of these errors is projected to increase in the sector. The factors that affect end user behavior are investigated in addition to an evaluation of the relation between system availability and human behavior. An investigation has been performed following the descriptive methodology in order to gain insights into human error factors. Questionnaires related to software/hardware errors and errors due to the end user were collected from 81 site workers. The findings indicate a potential relation between end user behavior and system availability. Training, experience, education, work shifts, system interface, usage of memory sticks and I/O devices were identified as factors affecting end user behavior, hence system availability and efficiency. © 2020 ACM.
Development and use of traditional patterns for design in hot arid zones
(2002) Shateh, Hadi Ali Suliman
ÖZET Çalışmamız, Libya'nın Gadames şehrindeki binaların çölün sert iklim şartlarına rağmen geniş bir deneyimle oluşturulan mimari şekli ile ilgili bilgilere dayanmaktadır. Bu tasarım, bir anonim tasarım metoduyla yüzlerce binayı tek bir binayla birleştiren bir bağlantıyı kurmayı başarmıştır. Çevresel uygunluğu yaratacak bir grup tasarım metodunu kullanarak sonuçlanan geleneksel mimari stilin günümüzde de ısıl seviyeye uygunluk göstermesi, yüzyıllardır değişmemiş olmasına rağmen çevresel yapının başarılı olduğunun ispatıdır. Ayrıca bu tasarım geleneksel çöl mimarisinin sıcak ve kurak bölgelerde bilimsel gerçeklerle uyumlu çevresel dindirme için mimarı tasannu da içermektedir. Bu tezde incelenen konu sıcak ve kurak bir bölgede bulunan. Eski Libya Gadames şehrindeki bina gruplarının durumudur. Buradaki binalar özel yapı şekline dayalı olarak çölde yaşayanların sosyal ve iklimi şartlarına uygun olacak şekilde adapte edilmiştir. Mesken binaları çok atlı ve birbirleriyle etkileşen binalar olup, bu binalar yollarda gölgeler yaratarak, direkt ve endirekt ısıl etkiyi büyük ölçüde azaltma yoluyla dengeli bir ısıl kütle oluşturmak üzere tasarlanmış olup binanın içe dönüklüğü ve dayalı bulunan tasarım metotlarının kullanılması ile dikey ve yatay sıcaklıkları izole etmektedirler. Bu tasarım, karmaşık kütlenin içerisinde bulunan genel ve özel hacimlerin, binalar grubunun ısıl muhafazası için yeteneğini artıran ve değişik yapı malzemelerinin fiziksel karakteristiklerini destekleyen bir korumayı mümkün kılmaktadır. Diğer bir acıdan ise, yol hacimleri ile farklı ev açıklıklarım kullanan, çok katlı binalar ve birleşik havalandırma sistemi, gündüz ile gece arasındaki sıcaklık farklarını uygun bir ortalamaya indirmek açısından yarar sağlamaktadır. vıMutfağın çatıya yerleştirilmesi ise bu alanın, büyük ölçüde ayrı kalmasını gerektiren sosyal ihtiyaçlara dolaylı olarak hizmet edecek şekilde esasen kadınlar tarafından kullanılmasına olanak sağlamaktadır. Bunlara ilaveten, çöl toplumunun bireyleri arasındaki güçlü bağ çevreye uygun yerleşim birimleri oluşturmada büyük bir etken olmuştur. Tasarım ve estetik bakımından hacimlerin dağılımı ve çeşitli elemanların iç tasannu, ısıl uygunluğun seviyesini desteklemekte pozitif bir rol oynamaktadır. Yan kapalı iç avlulara bağımlılık, iç hacimlerin doğal şekilde aydınlatılmasını sağlamaktadır. İçerideki soğuk hava ile dışarıdaki sıcak hava arasındaki basınç farkından faydalanan ve bu alanlar ile yol açıklıkları arasında bir havalandırma sistemi yaratılmaktadır. Dolayısıyla bu da ısıl kazancı azaltmaktadır. Yerel kültürü ifade eden renk seçimi ile düşük yayılımlı renkleri kullanan renklendirme metodunun çöl meskeni kompleksinin dışında bulunan iklim şartlarım yansıtmayan bir bizimde evin içindeki mikro iklim ile fonksiyonel elemanlarına güzellik katmadan büyük rolü olmaktadır. Bu tez çöldeki geleneksel yapı şeklinin karakteristiklerinden yukarıda açıklanan yöntemlerden yararlanarak geleneksel şekle en uygun tasarımının çıkartılması ve bunların ısıl olarak uygun, sosyal yönden kabul edilmiş ve onaylanmış ve ekonomik olarak da uygun hacimler yaratmada geleneksel tasarım ilkeleri oluşturarak modern teknikler kullanarak geliştirilmesi imkanını incelemektedir. Tezde yer alan öneriler geleneksel şekil ve yerel inşaat malzemelerini kullanarak dindirme metotlarına dayanmakta ısıl uygunluk yaratmak için gerekli olan çeşitli faktörleri elde edilmektedir. Önerilen tasarım, gölgelerin, havalandırmanın doğal aydınlatmanın ve aynı zamanda da ısıl olarak dengeli bir kütleye ilave olarak mahremiyet hususu ile ayrıca her bir hacimde faaliyetlerin yerine getirilmesi için de yeterli alam sağlamaktadır. Bu tezde değinilen yerel malzeme ve tasarım metotlarından yararlanılarak yapılan konut gruplarının tasarımına ilişkin öneriler çevresel faktörlere uygum göstermekte olup tasarlanan mimari modeller ve önerilen malzemeler de sürekli gelişmeye açıktır. Bu husus yerel mimari kimlik şeklinin geliştirilmesi ve özel mimari "sitilinin sürdürülmesi yönünde mütevazı bir adım sayılabilir.
Specifications of object oriented database systems and performance test of an object oriented database engine
(2002) Can, Barbaros
1990'ların başından bu yana nesne-yönelimli programlama bilgisayar dünyasında oldukça popüler hale gelmiştir. Bu eğilimin etkisiyle, geleneksel veri tabanı sistemlerinin eksikliklerini gidermek amacıyla nesne-yönelimli veri tabanı sistemleri ortaya çıkmıştır. Bu tez nesne-yönelimli veri tabanı sistemlerinin özelliklerini açıklamakta ve nesne-yönelimli veri tabanı sistemleri ile ilişkisel veri tabanı sistemleri arasında bazı karşılaştırmalar yapmaktadır. Tezin ilk iki bölümü çalışmanın teorik alt yapısını verirken, tezin üçüncü bölümü örnek bir uygulamaya dayanarak sistemleri karşılaştırmaktadır. Bu uygulamada nesne-yönelimli veri tabanı olarak db4o, büyüklük olarak her ikisi benzer ölçülerde olduklarından, ilişkisel veri tabanı olarak da MySql seçilmiştir. Uygulamanın programlanması için ise, tam bir nesne yönelimli programlama dili olan Java kullanılmıştır
Fail-safe e-mail server cluster with load balancing
(2004) Dayanır, Mahmut Mert
E-mail is one of the most well established, standardized and widely used communication methods available on the Internet. The 60% of all the messaging systems depend on e-mail systems. Linux as we all know is the free and well developed operating system used widely in the mail servers. Nowadays Linux mail solutions are preferred most of the service providers. The current growth of the Internet places increasing demands on both the hardware and software to deliver more mail to more users more quickly than ever before. There comes a point where a single server can no longer cope. For example this Project aimed to cope with 1.200.000 mail boxes which can not be achieved a single server. This is particularly a problem as the PC hardware m market, which provides affordable hardware for applications such as this, is driven by increasing processor speeds and not the increases in I/O that are required to shuffle increasing volumes of mail. Solution to this problem is to implement multiple email servers, make them parallel running servers to deal with the load. The first trials made with 4 computers each have different hardware configurations and various Linux operating systems, and they could implement 300.000 mail users. Implementing this is a manner that is transparent to users is non-trivial, but can yield significant benefits, providing both increased capacity and high availability.
Decoding of Polar Codes
(Springer Science and Business Media B.V., 2019) Gazi, O.
As we explained in Chap. 1, polar encoder structures can be constructed in a recursive manner. This leads to recursive decoding structures. In [1], Arıkan proposed successive cancellation decoding algorithm for the decoding of polar codes and derived recursive expression for the decoding operations. © Springer Nature Singapore Pte Ltd. 2019.
Software implementation of I2C bus into Zilog MCU
(2004) Yüzbaşoğlu, Fırat
This study describes the design and implementation of multi-master software PC bus on Zilog's z8 microcontrollers. PC bus is developed to support a com- munication integrated circuits (ICs) and microcontrollers on the same board. The bus is expanded from a single board to separated desks. During the data transmission, a fully software handshaking provides a synchronization between two asynchronized microcontrollers. There are many PC hardware integrated chips in the market. On these chips, start of the transmission is detected by polling. An interrupt based hardware start detection is designed to prevent waste of time and resources in this work. Testing results show that transmis sion speed of software PC bus on Z8 microcontrollers is reached to the PC bus standards of Philips Semiconductors Co
An analysis of the effects of modular furniture on preschool chıldren's group behaviours: A case study in Ankara
(2004) Can, Sıtkı Tankut
This study examines the effects of modular furniture on children's motor developments, group behavior and development. In order to determine preschool children behaviors and developmental criteria, necessary design criteria for preschool age period and kindergartens are investigated. Besides this, modular systems, design of place, psychological and social influences of environment which affect the child are stated. Within this framework focuses on 12 children between 5 and 6 age selected, by using systematic density observation technique.
Human prefarence for leisure in cafe a case study
(2004) Uluevli, Memduha Duygu
In this study, definition of leisure' and 'public leisure space' is examined. After an introduction to the concept of leisure, its types, and its relations with public life, the study discusses leisure as sodal activity and how leisure is related to public life. Caf£ is presented as a leisure space and its supportive role in public life is explored. The aim of this thesis is to determine the spatial and individual factors in public space and to explain how human behavior is influenced by these factors. Personal space, territoriality, privacy, crowding and density, and place attachment are considered as spatial factors. Age, gender, culture, and occupation are analyzed as individual factors. A research conducted in Ankara, in three different cafes, is presented as a study on the use of public space

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