{"id":20,"date":"2013-10-01T18:45:26","date_gmt":"2013-10-01T15:45:26","guid":{"rendered":"http:\/\/blog.metu.edu.tr\/veysi\/?page_id=20"},"modified":"2015-09-28T01:52:23","modified_gmt":"2015-09-27T22:52:23","slug":"master-or-ph-d-theses-supervised","status":"publish","type":"page","link":"https:\/\/blog.metu.edu.tr\/veysi\/research\/master-or-ph-d-theses-supervised\/","title":{"rendered":"Master or Ph.D. Theses Supervised"},"content":{"rendered":"<header id=\"headercont\">\n<div id=\"header\">\n<nav><b>In Progress<\/b><\/nav>\n<\/div>\n<\/header>\n<section id=\"maincont\">\n<section id=\"main\">\n<section id=\"mainleft\">\n<article><b>Ph.D.<\/b><\/p>\n<ol>\n<li>Safak Cevikbas, METU, CENG, 2008-<\/li>\n<li>Sercan Pekin, METU, II, 2012-<\/li>\n<li>\u00d6zlem G\u00fcr, B\u0130LKENT, CS, 2014-<\/li>\n<\/ol>\n<p><b>M.Sc.<\/b><\/p>\n<ol>\n<li>Semih Kek\u00fcl, METU, GATE<\/li>\n<li>Ayla Kara \u00c7oban, METU, GATE<\/li>\n<li>Murat \u00c7elik, METU, GATE<\/li>\n<li><\/li>\n<\/ol>\n<header>\n<h1><b style=\"font-family: 'Source Sans Pro', Helvetica, sans-serif;font-size: 16px;line-height: 1.5\">Completed<\/b><\/h1>\n<h1><b style=\"font-family: 'Source Sans Pro', Helvetica, sans-serif;font-size: 16px;line-height: 1.5\">Ph.D.<\/b><\/h1>\n<\/header>\n<ol>\n<li>Mehmet Fatih Uluat, METU, CENG, 2008-2014.<\/li>\n<li>Gokce Yildirim Kalkan, Efficient Rendering of Complex Scenes on Heterrogeneous Parallel Architectures, Computer Engineering, METU, 2014.<\/li>\n<li>Hatice Sancar, METU, CEIT, (with Assoc. Prof. Dr. Kursat Cagiltay), 2005-2010.<\/li>\n<li>Alphan Es, Accelerated Ray Tracing Using Programmable Graphics Pipelines, CENG, METU, 2008.<\/li>\n<li>Gurkan Koldas, Efficient Visibility Estimation for Distributed Virtual Urban Environments, (with Dr. W. Rynson Lau), CENG, METU, 2008.<\/li>\n<li>Erdal Yilmaz, Massive Crowds Simulation with Parallel Processing, Informatics Institute, Middle East Technical University, Ankara, Turkey, February 2010(with Prof. Dr. Yasemin Yardimci).<\/li>\n<\/ol>\n<p><b>M.Sc.<\/b><\/p>\n<ol>\n<li>Baris Yaman, Multiresolution Rendering of Terrain Height Fields, (with Prof. Dr. Volkan Atalay), CENG, METU, 1998.<\/li>\n<li>Ictem Ozkaya, Collision Detection for Articulated Bodies, CENG, METU, 1998.<\/li>\n<li>Halil Kolsuz, Development of an Internet-Based Asynchronous Learning System, CENG, METU, 1999.<\/li>\n<li>Varol Kaptan, Pottery Making and Clay Sculpting in a Virtual Environment, CENG, METU, 1999.<\/li>\n<li>Alphan S. Es, Optimized Rendering for Real-Time Three Dimensional Computer Animation, CENG, METU,1999.<\/li>\n<li>Gurkan Koldas, Multiresolution Behavioral Modeling in a Virtual Environment, CENG, METU, 2000<\/li>\n<li>Mehmet Ali Almis, HLA Compliant Tank Simulator, CENG, METU, 2001.<\/li>\n<li>Hacer Yalim Keles, Direct Volume Rendering on GPU, CENG, METU 2005.<\/li>\n<li>Mustafa Akin, Traffic Psychology and Drivers Behaviours, GAZI Univ, 2005<\/li>\n<li>Gokce Yildirim, Simulation of Smoke on GPU, CENG, METU, 2005<\/li>\n<li>Selman Duatepe, Soft Shadows on GPU, (with: Assoc. Prof. Dr. Harun Artuner), CENG, Hacettepe Univ. 2005<\/li>\n<li>Mahmut Bilgili, An Aquisition Model for Modelling and Simulation Systems, KHO, 2006<\/li>\n<li>Recep Donmez, A Simulation Based Aquisition Model, KHO, 2006<\/li>\n<li>Burak Ciflikli, Entitiy Motion Management in Complex Simulation Environments, CENG, METU, 2008.<\/li>\n<li>Caglar Unlu, Comparision of Parallel Ray-Casting on SIMD Multiprocessors and GPU, (with Dr. Cevat Sener), CENG, METU, 2008<\/li>\n<li>Tumer Topcu, Spatial Subdivisions for Fast Parallel Ray-Casting on MIMD Multiprocessors, (with Dr. Cevat Sener), CENG, METU, 2008<\/li>\n<li>Safak Burak Cevikbas, Visibility Based Prefetching with Simulated Annealing, CENG, METU, 2008<\/li>\n<li>Canku Alp Calargun, Modelling the Visual Effects and the Sea for Naval Surface Tactical Maneuvering Simulation System (NSTMSS) (with Assoc. Prof. Dr. Halit Oguztuzun), CENG, METU, 2008<\/li>\n<li>Selcuk Bozcan,A Tool For Network Simulation of Massively Multiplayer Online, CENG, METU, 2008.<\/li>\n<li>Ufuk Gun, Interactive Editing of Complex Terrains on Parallel Graphics Architectures, CENG,METU, 2009<\/li>\n<li>Serdar Yesilmurat, A Prefetching Method for Interactive Web GIS Applications, 2010.<\/li>\n<li>Seckin Sanci;, CENG, METU, A Parallel Algorithm for Flight Route Planning on GPU, 2010<\/li>\n<li>Efe Cem Kocabas, (with Assoc. Prof. Dr. Kursat Cagiltay),UML-ALF Agent Based Adaptive Learning Framework: A CAse Study on UML, CENG, METU, 2010<\/li>\n<li>Mustafa Murat Gun, A Fuzzy Linguistic Decision Model Approach for Selecting the Optimum Promotion Mix for Digital Products with Genetic Algorithms, CENG, METU, 2010<\/li>\n<\/ol>\n<\/article>\n<article><b>Abstracts<\/b><b>Thesis Title:<\/b>\u00a0POTTERY MAKING AND CLAY SCULPTING IN A VIRTUAL ENVIRONMENT<br \/>\n<b>Tez Ba\u015fl\u0131\u011f\u0131:<\/b>\u00a0SANAL ORTAMDA \u00c7\u00d6MLEK\u00c7\u0130L\u0130K VE K\u0130L HEYKELTIRASLIGI<br \/>\n<b>Name \/ \u0130sim:<\/b>\u00a0KAPTAN, VAROL<br \/>\n<b>Degree \/ Derece:<\/b>\u00a0M.S.<br \/>\n<b>Supervisor \/ Dan\u0131\u015fman:<\/b>\u00a0Asst. Prof. Dr. Veysi ISLER<br \/>\n<b>Cosupervisor \/ Ortak Dan\u0131\u015fman:<\/b>\u00a0&#8211;<br \/>\n<b>Department \/ B\u00f6l\u00fcm:<\/b>\u00a0Computer Engineering (CENG)<br \/>\n<b>Date \/ Tarih:<\/b>\u00a0September 1999<b>Abstract:<\/b><br \/>\nDeformable objects are an important area of research in computer graphics. This thesis introduces a non-physical model of a virtual clay-like substance and associated algorithms for very fast visualization of a deformation process as a result of human interaction. The proposed virtual clay model is based on key ideas from particle systems, voxel-based volume representations and implicit surfaces. Advanced modeling environment is provided through sophisticated input devices like virtual reality gloves and position trackers that allow every part of a human hand to be used in the deformation process. The experimental results show that modeling process has modest computational requirements and interactive frame rates can be achieved even on general purpose personal computers.<b>\u00d6z:<\/b><br \/>\nBicim degistirir nesneler, bilgisayar grafigi alaninin \u00f6nemli arastirma konularinin arasinda yer alir. Bu tezde, insan ile etkilesim yardimiyla nesne bicimlendirme islemini hizli g\u00f6rsellestirmeyi saglayan sanal kil malzemesi modeli ve ilgili algoritmalar sunulmaktadir. \u00d6nerilen sanal kil modeli, parcacik sistemleri, hacim elemani tabanli g\u00f6sterimleri ve \u00f6rt\u00fck y\u00fczeylerin sundugu temel fikirlere dayanilarak olusturulmustur. Bu y\u00f6ntemde, insan elinin her kisminin, bicimlendirme isleminde kullanilmasini saglayan sanal gerceklik eldivenleri ve konum izleyicileri gibi ileri cevre birimlerinin kullanilmasi ile gelismis bir modelleme ortami sunulmaktadir. Deneysel sonuclar, bu y\u00f6ntemin oldukca d\u00fcs\u00fck islem g\u00fcc\u00fc ve bellek gereksinimlerinin oldugunu ve genel amacli kisisel bilgisayarlarda bile etkilesimli cerceve hizlarina ulasilabildigini g\u00f6stermistir.<\/p>\n<hr \/>\n<p><b>Thesis Title:<\/b>\u00a0OPTIMIZED RENDERING FOR REAL TIME THREE DIMENSIONAL COMPUTER ANIMATION<br \/>\n<b>Tez Ba\u015fl\u0131\u011f\u0131:<\/b>\u00a0GER\u00c7EK ZAMANLI \u00dc\u00c7 BOYUTLU BILGISAYAR ANIMASYONU I\u00c7IN ENIYILENMIS G\u00d6R\u00dcNT\u00dc HESAPLANMASI<br \/>\n<b>Name \/ \u0130sim:<\/b>\u00a0ES, \u015e\u00fckr\u00fc Alphan<br \/>\n<b>Degree \/ Derece:<\/b>\u00a0M.S.<br \/>\n<b>Supervisor \/ Dan\u0131\u015fman:<\/b>\u00a0Assist. Prof. Dr. Veysi ISLER<br \/>\n<b>Cosupervisor \/ Ortak Dan\u0131\u015fman:<\/b>\u00a0&#8211;<br \/>\n<b>Department \/ B\u00f6l\u00fcm:<\/b>\u00a0Computer Engineering (CENG)<br \/>\n<b>Date \/ Tarih:<\/b>\u00a0December 1999<\/p>\n<p><b>Abstract:<\/b><br \/>\nReal time three dimensional computer animation has a wide range of application areas such as education, visual simulation, and entertainment. The main challenge behind the real time animation generation is to provide the highest possible visual quality in a limited amount of time. In order to produce the animation of a complex scene in real time rendering process should be optimized. Optimization requires using the system resources in a very efficient manner. One popular way to optimize the rendering process is using multiresolution modelling. In this thesis, an optimized rendering algorithm, which uses multiresolution modelling technique and a resource regulation mechanism will be introduced. Moreover, this algorithm is applied to a real world application as a case study. The application is a weather forecast presentation system for television studios. In this application it is necessary to render broadcast quality weather forecast animations in less than half an hour. The architectural details of this application and the integration of the introduced optimized rendering technique will also be discussed in the thesis.<\/p>\n<p><b>\u00d6z:<\/b><br \/>\nGer\u00e7ek zamanl\u0131 \u00fc\u00e7 boyutlu bilgisayar animasyonu e\u011fitim, g\u00f6rsel simulasyon ve e\u011flence gibi konular\u0131 kapsayan geni\u015f bir kullan\u0131m alan\u0131na sahiptir. Ger\u00e7ek zamanl\u0131 animasyon \u00fcretiminin arkas\u0131ndaki as\u0131l zorluk s\u0131n\u0131rl\u0131 zaman i\u00e7inde m\u00fcmk\u00fcn olan en y\u00fcksek g\u00f6rsel kaliteyi sa\u011flayabilmektir. Karma\u015f\u0131k sahnelerin ger\u00e7ek zamanl\u0131 animasyonlar\u0131n\u0131n haz\u0131rlanabilmesi i\u00e7in g\u00f6r\u00fcnt\u00fc \u00fcretimi i\u015flemi eniyilenmelidir. Eniyileme i\u015flemi sistem kaynaklar\u0131n\u0131n \u00e7ok etkin bir \u015fekilde kullan\u0131lmas\u0131n\u0131 gerektirir. Bu i\u015flem i\u00e7in en s\u0131k kullan\u0131lan y\u00f6ntemlerden biri \u00e7ok \u00e7\u00f6z\u00fcn\u00fcrl\u00fckl\u00fc modelleme tekni\u011fidir. Bu tezde \u00e7ok \u00e7\u00f6z\u00fcn\u00fcrl\u00fckl\u00fc modelleme ve kaynak kullan\u0131m\u0131n\u0131 d\u00fczenleyen mekanizmalar\u0131 i\u00e7eren bir eniyileme algoritmas\u0131 tan\u0131t\u0131lacakt\u0131r. Bununla birlikte tan\u0131t\u0131lan algoritma ger\u00e7ek bir uygulamada kullan\u0131lacakt\u0131r. Bu uygulama televizyon kanallar\u0131 i\u00e7in \u00fc\u00e7 boyutlu hava durumu sunumlar\u0131 haz\u0131rlamak i\u00e7in kullan\u0131lan bir animasyon program\u0131d\u0131r. Bu uygulama, yay\u0131n kalitesindeki animasyonlar\u0131 yar\u0131m saatten az bir s\u00fcrede ger\u00e7ekle\u015ftirebilmektedir. Program\u0131n mimari detaylar\u0131 ve eniyileme algoritmas\u0131n\u0131n entegrasyonu da tezde i\u015flenen konular aras\u0131ndad\u0131r.<\/p>\n<hr \/>\n<p><b>Thesis Title:<\/b>\u00a0MULTIRESOLUTION BEHAVIORAL MODELING IN A VIRTUAL ENVIRONMENT<br \/>\n<b>Tez Ba\u015fl\u0131\u011f\u0131:<\/b>\u00a0SANAL B\u0130R ORTAMDA \u00c7OK \u00c7\u00d6Z\u00dcN\u00dcRL\u00dcKL\u00dc DAVRANI\u015eSAL MODELLEME<br \/>\n<b>Name \/ \u0130sim:<\/b>\u00a0KOLDA\u015e, G\u00fcrkan<br \/>\n<b>Degree \/ Derece:<\/b>\u00a0M.S.<br \/>\n<b>Supervisor \/ Dan\u0131\u015fman:<\/b>\u00a0Assoc.Prof. Veysi ISLER<br \/>\n<b>Cosupervisor \/ Ortak Dan\u0131\u015fman:<\/b>\u00a0&#8211;<br \/>\n<b>Department \/ B\u00f6l\u00fcm:<\/b>\u00a0Computer Engineering (CENG)<br \/>\n<b>Date \/ Tarih:<\/b>\u00a0January 2000<\/p>\n<p><b>Abstract:<\/b><br \/>\nDynamic modeling provides realistic and natural looking motion in addition to better interaction with the user and better adaptation to changes in the environment. However, it has a disadvantage of computational cost since all necessary calculations are performed on the fly during the simulation. This deficiency limits the scene complexity as a real-time application. The major objective of this thesis is to speed up a physical simulation by making use of several levels of simulation details that is also called as multiresolution behavioral modeling based on the position of the observer. Multiple dynamically simulated sailing boats in a virtual lake are taken as a test environment for the implementation.<\/p>\n<p><b>\u00d6z:<\/b><br \/>\nDinamik modelleme kullan\u0131c\u0131 komutlar\u0131na ve ortam de\u011fi\u015fikliklerine an\u0131nda yan\u0131t vermenin yan\u0131 s\u0131ra ger\u00e7ek\u00e7i ve do\u011fal hareketlerin olu\u015fturulmas\u0131n\u0131 sa\u011flar. Fakat hesaplamalar\u0131n ger\u00e7ek zamanda yap\u0131lmalar\u0131 i\u015flemcilerin yo\u011fun hesaplamalar gerektiren uygulamalarda yetersiz kalmalar\u0131na neden olmaktad\u0131r. Bu k\u0131s\u0131tlama ger\u00e7ek zamanl\u0131 uygulamalarda yarat\u0131lan simulasyonun ger\u00e7ek\u00e7ili\u011fini s\u0131n\u0131rlamaktad\u0131r. Bu tez \u00e7al\u0131\u015fmas\u0131n\u0131n ana amac\u0131, g\u00f6zlemciye ba\u011fl\u0131 olarak belirlenen farkl\u0131 ayr\u0131nt\u0131 seviyesinde modeller kullanarak fiziksel simulasyonu h\u0131zland\u0131rmay\u0131 ama\u00e7lar. Bu y\u00f6nteme \u00e7ok \u00e7\u00f6z\u00fcn\u00fcrl\u00fckl\u00fc davran\u0131\u015fsal modelleme ad\u0131 verilir. Uygulama i\u00e7in \u00e7ok say\u0131da dinamik olarak modellenmi\u015f yelkenli teknenin bulundu\u011fu sanal bir g\u00f6l yarat\u0131lm\u0131\u015ft\u0131r.<\/p>\n<hr \/>\n<p><b>Thesis Title:<\/b>\u00a0SMOKE SIMULATION ON PROGRAMMABLE GRAPHICS HARDWARE<br \/>\n<b>Name \/ \u0130sim:<\/b>\u00a0Y\u0131ld\u0131r\u0131m, G\u00f6k\u00e7e<br \/>\n<b>Degree \/ Derece:<\/b>\u00a0M.S.<br \/>\n<b>Supervisor \/ Dan\u0131\u015fman:<\/b>\u00a0ISLER, Veysi<br \/>\n<b>Cosupervisor \/ Ortak Dan\u0131\u015fman:<\/b>\u00a0&#8211;<br \/>\n<b>Department \/ B\u00f6l\u00fcm:<\/b>\u00a0Computer Engineering (CENG)<br \/>\n<b>Date \/ Tarih:<\/b>\u00a0September 2005<\/p>\n<p><b>Abstract:<\/b><br \/>\nFluids such as smoke, water and fire are simulated for both Computer Graphics applications and engineering fields such as Mechanical Engineering. Generally, Fluid Dynamics is used for the achievement of realistic-looking fluid simulations. However, the complexity of these calculations makes it difficult to achieve high performance. With the advances in graphics hardware, it has been possible to provide programmability both at the vertex and the fragment level, which allows for faster simulations of complex fluids and other events. In this thesis, one gaseous fluid, smoke is simulated in three dimensions by solving Navier-Stokes Equations (NSEs) using a semi-Lagrangian unconditionally stable method. Simulation is performed both on Central Processing Unit (CPU) and Graphics Processing Unit (GPU). For the programmability at the vertex and the fragment level, C for Graphics (Cg), a platform-independent and architecture neutralshading language, is used.<\/p>\n<hr \/>\n<p><b>Thesis Title:<\/b>\u00a0DYNAMIC MODEL INTEGRATION AND 3D GRAPHICAL INTERFACE FOR A VIRTUAL SHIP<br \/>\n<b>Tez Ba\u015fl\u0131\u011f\u0131:<\/b>\u00a0SANAL B\u0130R GEM\u0130 \u0130\u00c7\u0130N D\u0130NAM\u0130K MODEL B\u0130RLE\u015eT\u0130R\u0130LMES\u0130 VE \u00dc\u00c7 BOYUTLU<br \/>\n<b>Name \/ \u0130sim:<\/b>\u00a0\u00c7alarg\u00fcn, Canku Alp<br \/>\n<b>Degree \/ Derece:<\/b>\u00a0M.S.<br \/>\n<b>Supervisor \/ Dan\u0131\u015fman:<\/b>\u00a0Assoc. Prof. Dr. Halit O\u011fuzt\u00fcz\u00fcn<br \/>\n<b>Cosupervisor \/ Ortak Dan\u0131\u015fman:<\/b>\u00a0Assoc. Prof. Dr. Veysi ISLER<br \/>\n<b>Department \/ B\u00f6l\u00fcm:<\/b>\u00a0Computer Engineering (CENG)<br \/>\n<b>Date \/ Tarih:<\/b>\u00a0January 2008<\/p>\n<p><b>Abstract:<\/b><br \/>\nThis thesis addresses the improvement of a physically based modeling simulator Naval Surface Tactical Maneuvering Simulation System (NSTMSS), that combines different simulators in a distributed environment by the help of High Level Architecture (HLA), to be used in naval tactical training systems. The objective is to upgrade a computer simulation program in which physical models are improved in order to achieve a more realistic movement of a ship in a virtual environment. The simulator will also be able to model the ocean waves and ship wakes for a more realistic view. The new naval model includes a 4 degrees of freedom (DOF) maneuvering model, and a wave model. The numerical results from real life are used for modeling purposes to increase the realism level of the simulator. Since the product at the end of the thesis work is needed to be a running computer code that can be integrated into the NSTMSS system, the code implementation and algorithm details are also covered. The comparisons between the wave models and physical models are evaluated for a better real time performance. The result of this thesis shows that the integration of a 4-DOF realistic ship model to the system improved the capability of NSTMSS to give more data to the student officers while making maneuvers. The result also indicates that the use of waves and ship wakes had taken the simulator to a next level in the environment perception.<\/p>\n<p><b>\u00d6z:<\/b><br \/>\nBu tezde, denizsel taktik e\u011fitim sistemlerinde kullan\u0131lacak, HLA\u2019in yard\u0131m\u0131yla birbirinden farkl\u0131, \u00e7e\u015fitli benzeticileri da\u011f\u0131t\u0131k bir ortamda birle\u015ftiren fiziksel tabanl\u0131 bir modelleme benzeticisi olan NSTMSS\u2019in geli\u015ftirilmesi konu al\u0131n\u0131r. Tezdeki ama\u00e7, bir bilgisayar benzetim program\u0131n\u0131n i\u00e7indeki fiziksel modelin geli\u015ftirilerek sanal ortamdaki bir geminin hareketlerinin sunumunun daha ger\u00e7ek\u00e7i bir g\u00f6sterimini elde etmektir. Benzetici, daha ger\u00e7ek\u00e7i bir g\u00f6r\u00fcn\u00fcm i\u00e7in okyanus dalgalar\u0131 ve gemi dalgalar\u0131n\u0131 da modelleyecektir. Deniz modeli, 4 serbestlik dereceli manevra modeli, ve dalga modeli i\u00e7ermektedir. Benzeticinin ger\u00e7ek\u00e7ilik seviyesini art\u0131rmak i\u00e7in ger\u00e7ek hayattan n\u00fcmerik veriler kullan\u0131lm\u0131\u015ft\u0131r. Tez \u00e7al\u0131\u015fmas\u0131n\u0131n sonundaki \u00fcr\u00fcn, NSTMSS\u2019e eklenecek cal\u0131\u015fmas\u0131 gereken bir bilgisayar program\u0131 olmas\u0131 gerekti\u011finden, kodlama ve algoritma ayr\u0131nt\u0131lar\u0131 da ele al\u0131nm\u0131\u015ft\u0131r. Dalga modelleri ve fiziksel modeller aras\u0131ndaki kar\u015f\u0131la\u015ft\u0131rmalar daha iyi bir ger\u00e7ek zaman performans\u0131 i\u00e7in ele al\u0131nm\u0131\u015ft\u0131r. Bu tezin sonucu, 4 serbestlik dereceli modelin NSTMSS\u2019e eklenmesinin, NSTMSS\u2019in \u00f6\u011frencilere manevra yaparlarken daha \u00e7ok bilgi verebilme kabiliyetini art\u0131rm\u0131\u015f oldu\u011funu g\u00f6sterir. Tezin g\u00f6rsel y\u00f6ndeki sonucu ise, dalgalar\u0131n ve de geminin arkas\u0131nda b\u0131rakt\u0131\u011f\u0131 dalgalar\u0131n kullan\u0131lmas\u0131n\u0131n \u00e7evre alg\u0131lamas\u0131nda benzeticiyi bir \u00fcst seviyeye ta\u015f\u0131d\u0131\u011f\u0131n\u0131 da belirtir.<\/p>\n<hr \/>\n<p><b>Thesis Title:<\/b>\u00a0ACCELERATED RAY TRACING USING PROGRAMMABLE GRAPHICS PIPELINES<br \/>\n<b>Tez Ba\u015fl\u0131\u011f\u0131:<\/b>\u00a0PROGRAMLANAB\u0130L\u0130R GRAF\u0130K \u0130\u015eLEMC\u0130LER\u0130 \u0130LE HIZLANDIRILMI\u015e I\u015eIN \u0130ZLEME<br \/>\n<b>Name \/ \u0130sim:<\/b>\u00a0Es, Alphan<br \/>\n<b>Degree \/ Derece:<\/b>\u00a0Ph.D.<br \/>\n<b>Supervisor \/ Dan\u0131\u015fman:<\/b>\u00a0Assoc. Prof. Dr. Veysi ISLER<br \/>\n<b>Cosupervisor \/ Ortak Dan\u0131\u015fman:<\/b>\u00a0&#8211;<br \/>\n<b>Department \/ B\u00f6l\u00fcm:<\/b>\u00a0Computer Engineering (CENG)<br \/>\n<b>Date \/ Tarih:<\/b>\u00a0January 2008<\/p>\n<p><b>Abstract:<\/b><br \/>\nThe graphics hardware have evolved from simple feed forward triangle rasterization devices to flexible, programmable, and powerful parallel processors. This evolution allows the researchers to use graphics processing units (GPU) for both general purpose computations and advanced graphics rendering. Sophisticated GPUs hold great opportunities for the acceleration of computationally expensive photorealistic rendering methods. Rendering of photorealistic images in real-time is a challenge. In this work, we investigate efficient ways to utilize GPUs for real-time photorealistic rendering. Specifically, we studied uniform grid based ray tracing acceleration methods and GPU friendly traversal algorithms. We show that our method is faster than or competitive to other GPU based ray tracing acceleration techniques. The proposed approach is also applicable to the fast rendering of volumetric data. Additionally, we devised GPU based solutions for real-time stereoscopic image generation which can be used in companion with GPU based ray tracers.<\/p>\n<p><b>\u00d6z:<\/b><br \/>\nGrafik donan\u0131mlar\u0131 zamanla sadece yollanan \u00fc\u00e7genleri \u00e7izen basit cihazlardan; \u00e7ok y\u00f6nl\u00fc, programlanabilir ve g\u00fc\u00e7l\u00fc paralel i\u015flemcilere d\u00f6n\u00fc\u015ft\u00fcler. Bu evrimle\u015fme grafik hesaplama \u00fcnitelerinin (GPU) genel ama\u00e7l\u0131 hesaplamalarda oldu\u011fu kadar, ileri g\u00f6r\u00fcnt\u00fc sentezleme hesaplamalar\u0131nda kullan\u0131lmas\u0131na da olanak tan\u0131d\u0131. Sofistike GPUlar y\u00fcksek hesaplama g\u00fcc\u00fc gerektiren foto ger\u00e7ek\u00e7i g\u00f6r\u00fcnt\u00fc \u00fcretiminin h\u0131zland\u0131r\u0131lmas\u0131 konusunda pek \u00e7ok olanak sunmaktad\u0131rlar. Foto ger\u00e7ek\u00e7i g\u00f6r\u00fcnt\u00fclerin ger\u00e7ek zamanda hesaplanmas\u0131 hen\u00fcz \u00e7\u00f6z\u00fcme kavu\u015fturulmam\u0131\u015f bir aland\u0131r. Bu \u00e7al\u0131\u015fmada, GPUlar\u0131n ger\u00e7ek zamanl\u0131 foto ger\u00e7ek\u00e7i g\u00f6r\u00fcnt\u00fc \u00fcretiminde etkin kullan\u0131m\u0131na y\u00f6nelik y\u00f6ntemler ara\u015ft\u0131r\u0131lm\u0131\u015ft\u0131r. \u00d6zellikle d\u00fczg\u00fcn \u0131zgaralama veri yap\u0131s\u0131 ile, \u00e7ok kullan\u0131lan bir foto ger\u00e7ek\u00e7i g\u00f6r\u00fcnt\u00fc hesaplama y\u00f6ntemi olan \u0131\u015f\u0131n izlemenin GPU \u00fczerinde h\u0131zland\u0131r\u0131lmas\u0131 ele al\u0131nm\u0131\u015ft\u0131r. Tezde, geli\u015ftirdi\u011fimiz GPU tabanl\u0131 \u0131\u015f\u0131n izleme metodunun di\u011fer GPU tabanl\u0131 y\u00f6ntemlere g\u00f6re kar\u015f\u0131la\u015ft\u0131r\u0131labilir veya pek \u00e7ok sahne i\u00e7in daha h\u0131zl\u0131 performans sergiledi\u011fi g\u00f6sterilmi\u015ftir. Yine bu metodun hacimsel verilerin h\u0131zl\u0131 g\u00f6r\u00fcnt\u00fclenmesinde de kullan\u0131labilece\u011fi g\u00f6sterilmi\u015ftir. Ek olarak, GPU tabanl\u0131 h\u0131zl\u0131 stereo g\u00f6r\u00fcnt\u00fc \u00fcretimi y\u00f6ntemleri geli\u015ftirilmi\u015f ve bu y\u00f6ntemlerin GPU tabanl\u0131 \u0131\u015f\u0131n izleyicilerle etkin bir \u015fekilde kullan\u0131labilece\u011fi g\u00f6sterilmi\u015ftir.<\/p>\n<hr \/>\n<p><b>Thesis Title:<\/b>\u00a0TASK PARALLELISM FOR RAY TRACING ON A GPU CLUSTER<br \/>\n<b>Tez Ba\u015fl\u0131\u011f\u0131:<\/b>\u00a0\u00c7\u0130ZGE \u0130\u015eLEM B\u0130R\u0130M\u0130 K\u00dcMES\u0130 \u00dcZER\u0130NDE I\u015eIN \u0130ZLEME \u0130\u00c7\u0130N G\u00d6REV KO\u015eUTLU\u011eU<br \/>\n<b>Name \/ \u0130sim:<\/b>\u00a0\u00dcnl\u00fc, \u00c7a\u011flar<br \/>\n<b>Degree \/ Derece:<\/b>\u00a0M.S.<br \/>\n<b>Supervisor \/ Dan\u0131\u015fman:<\/b>\u00a0Assoc. Prof. Dr. Veysi ISLER<br \/>\n<b>Cosupervisor \/ Ortak Dan\u0131\u015fman:<\/b>\u00a0Dr. Cevat \u015eener<br \/>\n<b>Department \/ B\u00f6l\u00fcm:<\/b>\u00a0Computer Engineering (CENG)<br \/>\n<b>Date \/ Tarih:<\/b>\u00a0February 2008<\/p>\n<p><b>Abstract:<\/b><br \/>\nRay tracing is a computationally complex global illumination algorithm that is used for producing realistic images. In addition to parallel implementations on commodity PC clusters, recently, Graphics Processing Units (GPU) have also been used to accelerate ray tracing. In this thesis, ray tracing is accelerated on a GPU cluster where the viewing plane is divided into unit tiles. Slave processes work on these tiles in a task parallel manner which are dynamically assigned to them. To decrease the number of ray-triangle intersection tests, Bounding Volume Hierarchies (BVH) are used. It is shown that almost linear speedup can be achieved. On the other hand, it is observed that API and network overheads are obstacles for scalability.<\/p>\n<p><b>\u00d6z:<\/b><br \/>\nI\u015f\u0131n izleme, ger\u00e7ek\u00e7i g\u00f6r\u00fcnt\u00fcler \u00fcretmek i\u00e7in kullan\u0131lan ve hesaplama bak\u0131m\u0131ndan pahal\u0131 olan bir genel ayd\u0131nlatma algoritmas\u0131d\u0131r. Ki\u015fisel bilgisayarlar \u00fczerine kurulan k\u00fcmelere ek olarak, son zamanlarda \u00e7izge i\u015flem birimlerinde de \u0131\u015f\u0131n izleme h\u0131zland\u0131r\u0131lm\u0131\u015ft\u0131r. Bu tezde, \u0131\u015f\u0131n izleme bir \u00e7izge i\u015flem birimi k\u00fcmesi \u00fczerinde g\u00f6r\u00fcnt\u00fc d\u00fczlemi birim d\u00f6\u015felere b\u00f6l\u00fcnerek h\u0131zland\u0131r\u0131lm\u0131\u015ft\u0131r. K\u00f6le i\u015flemler, kendilerine devingen olarak atanan d\u00f6\u015feler \u00fczerinde g\u00f6rev ko\u015futlu\u011fu ile \u00e7al\u0131\u015fmaktad\u0131r. I\u015f\u0131n-\u00fc\u00e7gen kesi\u015fimi testlerinin say\u0131s\u0131n\u0131 azaltmak i\u00e7in saran hacim hiyerar\u015fileri kullan\u0131lm\u0131\u015ft\u0131r. Neredeyse do\u011frusal h\u0131zlanmalar\u0131n elde edilebilece\u011fi g\u00f6sterilmi\u015ftir. Di\u011fer taraftan, uygulama programla aray\u00fcz\u00fc ve a\u011f ek y\u00fcklerinin \u00f6l\u00e7eklenebilirli\u011fe engel olduklar\u0131 g\u00f6zlemlenmi\u015ftir.<\/p>\n<hr \/>\n<p><b>Thesis Title:<\/b>\u00a0VISIBILITY BASED PREFETCHING WITH SIMULATED ANNEALING<br \/>\n<b>Tez Ba\u015fl\u0131\u011f\u0131:<\/b>\u00a0G\u00d6R\u00dcN\u00dcRL\u00dcK TABANLI OLASILIKSAL ERKEN OKUMA<br \/>\n<b>Name \/ \u0130sim:<\/b>\u00a0\u00c7evikba\u015f, \u015eafak Burak<br \/>\n<b>Degree \/ Derece:<\/b>\u00a0M.S.<br \/>\n<b>Supervisor \/ Dan\u0131\u015fman:<\/b>\u00a0Assoc. Prof. Dr. Veysi ISLER<br \/>\n<b>Cosupervisor \/ Ortak Dan\u0131\u015fman:<\/b>\u00a0&#8211;<br \/>\n<b>Department \/ B\u00f6l\u00fcm:<\/b>\u00a0Computer Engineering (CENG)<br \/>\n<b>Date \/ Tarih:<\/b>\u00a0January 2008<\/p>\n<p><b>Abstract:<\/b><br \/>\nComplex urban scene rendering is not feasible without culling invisible geometry before the rendering actually takes place. Visibility culling can be performed on predefined regions of scene where for each region a potential visible set of scene geometry is computed. Rendering cost is reduced since instead of a bigger set only a single PVS which is associated with the region of the viewer is rendered. However, when the viewer leaves a region and enters one of its neighbors, disposing currently loaded PVS and loading the new PVS causes stalls. Prefetching policies are utilized to overcome stalls by loading PVS of a region before the viewer enters it. This study presents a prefetching method for interactive urban walkthroughs. Regions and transitions among them are represented as a graph where the regions are the nodes and transitions are the edges. Groups of nodes are formed according to statistical data of transitions and used as the prefetching policy. Some heuristics for constructing groups of nodes are developed and Simulated Annealing is utilized for constructing optimized groups based on developed heuristics. The proposed method and underlying application of Simulated Annealing are customized for minimizing average transition cost.<\/p>\n<p><b>\u00d6z:<\/b><br \/>\nKarma\u015f\u0131k \u015fehir ortamlar\u0131, herhangi bir ay\u0131klama kullan\u0131lmadan ger\u00e7eklenebilir de\u011fillerdir. Ay\u0131klama yapmak i\u00e7in kullan\u0131lan bir y\u00f6ntem, sahneyi h\u00fccrelere b\u00f6lmek ve her h\u00fccreye bir g\u00f6r\u00fcnebilir nesneler k\u00fcmesi atamakt\u0131r. Sadece izleyicinin bulundu\u011fu h\u00fccrenin g\u00f6r\u00fcnebilir nesne k\u00fcmesinin ger\u00e7eklenmesi, b\u00fct\u00fcn sahne ya da sahnenin b\u00fcy\u00fck bir k\u0131sm\u0131n\u0131n ger\u00e7eklenmesine g\u00f6re \u00e7ok daha az kaynak gerektirir. Buna ra\u011fmen ak\u0131c\u0131 bir ger\u00e7ekleme i\u00e7in h\u00fccre ge\u00e7i\u015flerindeki yava\u015flaman\u0131n \u00fcstesinden gelinmelidir. Bu sorunu a\u015fmak i\u00e7in kullan\u0131lan yakla\u015f\u0131ma erken y\u00fckleme ad\u0131 verilir. Erken y\u00fckleme ile ger\u00e7ekleme i\u00e7in gerekli veri daha izleyici h\u00fccreye girmeden \u00f6nce y\u00fcklenir. Bu \u00e7al\u0131\u015fma \u015fehir ortam\u0131nda etkile\u015fimli gezinti uygulamalar\u0131 i\u00e7in kullan\u0131labilecek bir erken y\u00fckleme y\u00f6ntemi sunar. Y\u00f6ntem sahneyi bir \u00e7izge olarak ifade eder ve bu \u00e7izge \u00fczerinde d\u00fc\u011f\u00fcm gruplar\u0131 tan\u0131mlar. Tan\u0131mlanan gruplar erken y\u00fckleme i\u00e7in girdi olarak kullan\u0131l\u0131r. Gruplar\u0131n olu\u015fturulmas\u0131 i\u00e7in Benzetimli Tavlama algoritmas\u0131 ve bulu\u015fsallar. Y\u00f6ntem ortalama ge\u00e7i\u015f masraf\u0131n\u0131n azalt\u0131lmas\u0131 ya da en y\u00fcksek ge\u00e7i\u015f masraf\u0131n\u0131n azalt\u0131lmas\u0131 gibi farkl\u0131 ama\u00e7lar i\u00e7in \u00f6zelle\u015ftirilebilir.<\/p>\n<hr \/>\n<p><b>Thesis Title:<\/b>\u00a0EFFICIENT VISIBILITY ESTIMATION FOR DISTRIBUTED VIRTUAL URBAN ENVIRONMENTS<br \/>\n<b>Tez Ba\u015fl\u0131\u011f\u0131:<\/b>\u00a0DA\u011eITIK SANAL \u015eEH\u0130R ORTAMLARI \u0130\u00c7\u0130N ETK\u0130N G\u00d6R\u00dcN\u00dcRL\u00dcK KEST\u0130R\u0130M\u0130<br \/>\n<b>Name \/ \u0130sim:<\/b>\u00a0Kolda\u015f, G\u00fcrkan<br \/>\n<b>Degree \/ Derece:<\/b>\u00a0Ph.D.<br \/>\n<b>Supervisor \/ Dan\u0131\u015fman:<\/b>\u00a0Assoc. Prof. Dr. Veysi ISLER<br \/>\n<b>Cosupervisor \/ Ortak Dan\u0131\u015fman:<\/b>\u00a0Prof. Dr. Rynson Wh Lau<br \/>\n<b>Department \/ B\u00f6l\u00fcm:<\/b>\u00a0Computer Engineering (CENG)<br \/>\n<b>Date \/ Tarih:<\/b>\u00a0February 2008<\/p>\n<p><b>Abstract:<\/b><br \/>\nThis research focuses on the utilization of occlusion culling for the real-time visualization of distributed virtual urban environments. Today&#8217;s graphics hardware renders all the primitives in any order and uses z-buffer to determine which primitives are visible on a per-pixel basis. However, visibility is computed in the last stage of rendering pipeline and every rendered primitive is not visible in the final image. Early culling of the invisible primitives in a complex scene is valuable for efficiency in the conventional rendering pipeline. This may reduce the number of primitives that will be processed in the rest of the pipeline. In this thesis, we propose an efficient visibility estimation method for distributed virtual urban environments. The proposed method is based on occlusion culling to identify and cull the occluded parts of the scene. This not only computes conservative potential visible set (PVS) for each client but also assures the computed PVS to be available at the client on-time and reduces the network traffic by grouping the clients which may see each others dynamically.<\/p>\n<p><b>\u00d6z:<\/b><br \/>\nBu ara\u015ft\u0131rma da\u011f\u0131t\u0131k sanal kentsel ortamlar\u0131n ger\u00e7ek zamanl\u0131 g\u00f6rselle\u015ftirilmesi i\u00e7in kapatma ay\u0131klamas\u0131 kullan\u0131m\u0131 merkezlidir. G\u00fcn\u00fcm\u00fcz grafik donan\u0131mlar\u0131 t\u00fcm temel \u00f6\u011feleri her hangi bir s\u0131rada ger\u00e7eklemekte ve z-arabelle\u011fi kullanarak piksel seviyesinde g\u00f6r\u00fcnebilir olanlar\u0131 belirlemektedir. Ancak, g\u00f6r\u00fcn\u00fcrl\u00fck g\u00f6rsel ger\u00e7ekleme ard\u0131\u015f\u0131k d\u00fczeninin en son a\u015famas\u0131nda hesaplanmakta ve ger\u00e7eklenen her bir temel \u00f6\u011fe en son g\u00f6r\u00fcnt\u00fcde g\u00f6r\u00fcnmemektedir. Karma\u015f\u0131k sahnelerde g\u00f6r\u00fcnmeyen temel \u00f6\u011felerin erken ay\u0131klanmas\u0131 g\u00f6rsel ger\u00e7ekleme ard\u0131\u015f\u0131k d\u00fczeninde etkinlik a\u00e7\u0131s\u0131ndan \u00f6nemlidir. Bu sayede g\u00f6rsel ger\u00e7ekleme ard\u0131\u015f\u0131k d\u00fczeninin geri kalan k\u0131sm\u0131nda i\u015flenecek olan temel \u00f6\u011fe say\u0131s\u0131 azalt\u0131labilir. Bu tezde, da\u011f\u0131t\u0131k sanal \u015fehir ortamlar\u0131 i\u00e7in etkin bir g\u00f6r\u00fcn\u00fcrl\u00fck hesaplama y\u00f6ntemi \u00f6nerilmektedir. \u00d6nerilen y\u00f6ntem, sahnenin g\u00f6r\u00fcnmeyen k\u0131s\u0131mlar\u0131n\u0131n tan\u0131mlanmas\u0131 ve ay\u0131klanmas\u0131 amac\u0131yla kapatma ay\u0131klamas\u0131 temellidir. Bu sayede her bir kat\u0131l\u0131mc\u0131 i\u00e7in kararl\u0131 Muhtemel G\u00f6r\u00fcn\u00fcrler K\u00fcmesi (MGK) hesaplanmakla kalmaz ayr\u0131ca hesaplanan MGK\u2019nin zaman\u0131nda kat\u0131l\u0131mc\u0131da olmas\u0131 garanti edilir ve dinamik olarak birbirini g\u00f6rebilecek kat\u0131l\u0131mc\u0131lar\u0131n gruplanmas\u0131 ile a\u011f trafi\u011fi azalt\u0131l\u0131r.<\/p>\n<hr \/>\n<p><b>Thesis Title:<\/b>\u00a0DATA PARALLELISM FOR RAY CASTING LARGE SCENES ON A CPU-GPU CLUSTER<br \/>\n<b>Tez Ba\u015fl\u0131\u011f\u0131:<\/b>\u00a0ANA \u0130\u015eLEM B\u0130R\u0130M\u0130-\u00c7\u0130ZGE \u0130\u015eLEM B\u0130R\u0130M\u0130 K\u00dcMES\u0130 \u00dcZER\u0130NDE B\u00dcY\u00dcK SAHNELER I\u015eIN HESAPLAMA \u0130\u00c7\u0130N VER\u0130 KO\u015eUTLU\u011eU<br \/>\n<b>Name \/ \u0130sim:<\/b>\u00a0Topcu, T\u00fcmer<br \/>\n<b>Degree \/ Derece:<\/b>\u00a0M.S.<br \/>\n<b>Supervisor \/ Dan\u0131\u015fman:<\/b>\u00a0Assoc. Prof. Dr. Veysi ISLER<br \/>\n<b>Cosupervisor \/ Ortak Dan\u0131\u015fman:<\/b>\u00a0Assist. Prof. Dr. Cevat \u015eener<br \/>\n<b>Department \/ B\u00f6l\u00fcm:<\/b>\u00a0Computer Engineering (CENG)<br \/>\n<b>Date \/ Tarih:<\/b>\u00a0May 2008<\/p>\n<p><b>Abstract:<\/b><br \/>\nIn the last decade, computational power, memory bandwidth and programmability capabilities of graphics processing units (GPU) have rapidly evolved. Therefore, many researches have been performed to use GPUs in advanced graphics rendering. Because of its high degree of it parallelism, ray tracing has been one of the rst algorithms studied on GPUs. However, the rendering of large scenes with ray tracing can easily exceed the GPU<\/p>\n<p><b>\u00d6z:<\/b><br \/>\nSon birka\u00e7 y\u0131lda \u00e7izge i\u015flem birimlerinin (GPU) i\u015flem g\u00fcc\u00fc, bellek bant geni\u015fli\u011fi ve programlanabilme yetenekleri h\u0131zl\u0131 bir \u015fekilde geli\u015fti. Bu ger\u00e7ekler g\u00f6z \u00f6n\u00fcne al\u0131narak GPUlar\u0131 ileri \u00e7izge sentezleme alanlar\u0131nda kullanmak i\u00e7in pek \u00e7ok ara\u015ft\u0131rma yap\u0131ld\u0131. I\u015f\u0131n izleme, y\u00fcksek derecedeki ko\u015futlu\u011fu sebebiyle GPUlar \u00fczerinde \u00e7al\u0131\u015f\u0131lan ilk konulardan birisi oldu. Ancak b\u00fcy\u00fck sahnelerin \u0131\u015f\u0131n izleme ile ger\u00e7eklenmesi GPUnun bellek kapasitesini kolayl\u0131kla a\u015fabilir. Bu \u00e7al\u0131\u015fmada ortaya konan algoritma, sahnenin par\u00e7alara ayr\u0131larak ortaya \u00e7kan her bir par\u00e7an\u0131n bir k\u00fcmede bulunan CPU-GPU \u00e7iftlerine atand\u0131\u011f\u0131 veri ko\u015fut bir yakla\u015f\u0131m kullanmaktadr. Algoritmam\u0131z daha \u00e7ok hacimsel verilerin g\u00f6rsellenmesinde kullan\u0131lan ve \u0131\u015f\u0131n izlemenin \u00f6zel bir durumu olan \u0131\u015f\u0131n hesaplama \u00fczerine yo\u011funla\u015fmaktad\u0131r. CPUlar ak\u0131\u015f denetimi ve dallanmada olduk\u00e7a verimliyken GPUlar y\u00fcksek miktarda kayan nokta i\u015flemi gerektiren uygulamalarda olduk\u00e7a h\u0131zl\u0131d\u0131r. Bu ger\u00e7eklere dayanarak k\u00fcmedeki GPUlar \u0131\u015f\u0131n hesaplama g\u00f6revine, CPUlar ise \u0131\u015f\u0131nlar\u0131 hareket ettirme g\u00f6revine atanm\u0131\u015ft\u0131r. Sonu\u00e7 olarak CPU ve GPUlar\u0131 verimli bir \u015fekilde kullanarak b\u00fcy\u00fck sahneleri g\u00f6rsellemeyi ba\u015fard\u0131k ve performans\u0131n y\u00fck dengesizli\u011fi sebebiyle bak\u0131\u015f a\u00e7\u0131s\u0131na olduk\u00e7a ba\u011fl\u0131 oldu\u011funu g\u00f6zlemledik.<\/p>\n<hr \/>\n<p><b>Thesis Title:<\/b>\u00a0A TOOL FOR NETWORK SIMULATION OF MASSIVELY MULTIPLAYER ONLINE GAMES<br \/>\n<b>Tez Ba\u015fl\u0131\u011f\u0131:<\/b>\u00a0DEVASA OYUNCULU \u00c7EVR\u0130M\u0130\u00c7\u0130 OYUNLAR \u0130\u00c7\u0130N B\u0130R A\u011e BENZET\u0130M ARACI<br \/>\n<b>Name \/ \u0130sim:<\/b>\u00a0Bozcan, Sel\u00e7uk<br \/>\n<b>Degree \/ Derece:<\/b>\u00a0M.S.<br \/>\n<b>Supervisor \/ Dan\u0131\u015fman:<\/b>\u00a0Assoc. Prof. Dr. Veysi ISLER<br \/>\n<b>Cosupervisor \/ Ortak Dan\u0131\u015fman:<\/b>\u00a0&#8211;<br \/>\n<b>Department \/ B\u00f6l\u00fcm:<\/b>\u00a0Computer Engineering (CENG)<br \/>\n<b>Date \/ Tarih:<\/b>\u00a0September 2008<\/p>\n<p><b>Abstract:<\/b><br \/>\nMassively multiplayer online games (MMOGs) have become highly popular in the last decade and now attract millions of users from all over the world to play in an evolving virtual world concurrently over the Internet. The high popularity of MMOGs created a rapidly growing market and this highly dynamic market has forced the game developers to step up competitively. However, MMOG development is a challenging and expensive process. In this study, we have developed a network simulation tool which can be used to model and simulate typical MMOGs that have client-server architectures. The main objective is to provide a simulation environment to MMOG developers that could be used to test, analyze and verify various aspects of the MMOG network architecture. We have also implemented a graphical user interface which allows constructing the simulation model visually. We have demonstrated the use of simulation tool by experimental simulations.<\/p>\n<p><b>\u00d6z:<\/b><br \/>\nDevasa oyunculu \u00e7evrim i\u00e7i oyunlar (MMOG) son on y\u0131l i\u00e7erisinde son derece pop\u00fcler oldular. G\u00fcn\u00fcm\u00fczde d\u00fcnyan\u0131n d\u00f6rt bir yan\u0131ndan milyonlarca kisi, internet \u00fczerinden eszamanl\u0131 olarak oynanan ve s\u00fcrekli evrimlesen sanal bir d\u00fcnyaya sahip olan bu oyunlar taraf\u0131ndan \u00e7ekilmektedirler. MMOG\u2019lerin bu y\u00fcksek pop\u00fclaritesi d\u00fcnya genelinde olduk\u00e7a h\u0131zl\u0131 bir b\u00fcy\u00fcme g\u00f6steren bir market olusturdu. Bu son derece dinamik market, oyun gelistirici firmalar\u0131 rekabet\u00e7i bir tutum sergilemeye zorlad\u0131. Fakat MMOG gelistirme s\u00fcreci zorlu ve pahal\u0131 bir s\u00fcre\u00e7tir. Bu \u00e7al\u0131smada biz, tipik sunucu-istemci mimarisine sahip MMOG a\u011flar\u0131n\u0131 modellemek ve benzetimini yapmak amac\u0131yla kullan\u0131labilecek bir a\u011f benzetimi arac\u0131 gelistirdik. As\u0131l amac\u0131m\u0131z MMOG gelistiricilerinin oyun gelistirme s\u00fcrecinde MMOG a\u011flar\u0131n\u0131n farkl\u0131 y\u00f6nlerini test etmek, analiz etmek ve do\u011frulamak i\u00e7in kullanabilece\u011fi bir a\u011f benzetim ortam\u0131 sunmakt\u0131r. Bu \u00e7al\u0131sma s\u0131ras\u0131nda benzetim modellerinin grafiksel olarak tasarlanabilece\u011fi g\u00f6rsel bir ara\u00e7 da gelistirilmistir. \u00c7al\u0131smam\u0131z d\u00e2hilinde gelistirdi\u011fimiz a\u011f benzetim ortam\u0131n\u0131n kullan\u0131m\u0131n\u0131 ger\u00e7eklestirdi\u011fimiz \u00e7esitli deneysel a\u011f benzetimleriyle \u00f6rnekledik.<\/p>\n<hr \/>\n<p><b>Thesis Title:<\/b>\u00a0INTERACTIVE EDITING OF COMPLEX TERRAINS ON PARALLEL GRAPHICS ARCHITECTURES<br \/>\n<b>Tez Ba\u015fl\u0131\u011f\u0131:<\/b>\u00a0MODEL-BASED APPROACH TO THE FEDERATION OBJECT MODEL INDEPENDENCE PROBLEM<br \/>\n<b>Name \/ \u0130sim:<\/b>\u00a0G\u00fcn, Ufuk<br \/>\n<b>Degree \/ Derece:<\/b>\u00a0M.S.<br \/>\n<b>Supervisor \/ Dan\u0131\u015fman:<\/b>\u00a0Assoc. Prof. Dr. Veysi ISLER<br \/>\n<b>Cosupervisor \/ Ortak Dan\u0131\u015fman:<\/b>\u00a0&#8211;<br \/>\n<b>Department \/ B\u00f6l\u00fcm:<\/b>\u00a0Computer Engineering (CENG)<br \/>\n<b>Date \/ Tarih:<\/b>\u00a0September 2009<\/p>\n<p><b>Abstract:<\/b><br \/>\nRendering large terrains on large screens at interactive frame rates is a challenging area of computer graphics. In the last decade, real-time terrain rendering on large screens played a significant role in various simulations and virtual reality systems. To fulfill the demand of these systems, two software tools are developed. The first tool is a Terrain Editor that creates and manipulates large terrains. The second is a Multi-Display Viewer that displays the created terrains on multiple screens. Since the typical large terrains consist of many polygons, graphics boards might have difficulties in rendering the terrain at interactive frame rates. The common solution to this problem is to use terrain simplification without losing image quality. To this purpose, in this study, a paged level of detail mechanism that works with multiple threads is developed and integrated on multiple screen display systems to increase the performance of the high resolution systems.<\/p>\n<p><b>\u00d6z:<\/b><br \/>\nY\u00fcksek \u00e7\u00f6z\u00fcn\u00fcrl\u00fckl\u00fc ekranlarda b\u00fcy\u00fck arazileri y\u00fcksek \u00e7er\u00e7eve say\u0131s\u0131nda g\u00f6rselle\u015ftirmek bilgisayar grafi\u011finin zor konular\u0131ndan biridir. Son y\u0131llarda, bu konu bir\u00e7ok sim\u00fclasyon ve sanal ger\u00e7eklik sistemlerinin ihtiyac\u0131 haline gelmi\u015ftir. Bu talebi kar\u015f\u0131lamak i\u00e7in iki \u00f6nemli uygulama geli\u015ftirilmi\u015ftir. Bunlardan ilki arazi yaratan ve \u015fekillendiren Arazi Edit\u00f6r\u00fc, ikincisi ise bu arazileri \u00e7oklu ekranlarda g\u00f6rselle\u015ftiren \u00c7oklu-Ekran G\u00f6rselle\u015ftiricisidir. B\u00f6yle b\u00fcy\u00fck araziler \u00e7ok fazla \u00e7okgenden olu\u015ftu\u011fu i\u00e7in, grafik kartlar\u0131 bu t\u00fcr ger\u00e7ek zamanl\u0131 \u00e7er\u00e7eve oran\u0131nda g\u00f6rsellemekte s\u0131k\u0131nt\u0131 ya\u015far. Bu sorunun genel \u00e7\u00f6z\u00fcm\u00fc arazinin g\u00f6r\u00fcnt\u00fc kalitesinde kay\u0131p ya\u015fanmadan arazi \u00fczerindeki dokular\u0131n ve \u00fc\u00e7genlerin basitle\u015ftirilmesidir. Bu ama\u00e7la, bu \u00e7al\u0131\u015fmada, arazileri par\u00e7alara ay\u0131ran ve bu par\u00e7alar\u0131 farkl\u0131 detay seviyelerinde g\u00f6rselle\u015ftiren bir mekanizma geli\u015ftirilmi\u015ftir. Daha sonra bu mekanizma \u00e7oklu ekranl\u0131 sistemle birle\u015ftirilerek y\u00fcksek \u00e7\u00f6z\u00fcn\u00fcrl\u00fckl\u00fc hale getirilmi\u015ftir.<\/p>\n<hr \/>\n<p><b>Thesis Title:<\/b>\u00a0A PREFETCHING METHOD FOR INTERACTIVE WEB GIS APPLICATIONS<br \/>\n<b>Tez Ba\u015fl\u0131\u011f\u0131:<\/b>\u00a0ETK\u0130LE\u015e\u0130ML\u0130 WEB GIS UYGULAMALARI \u0130\u00c7\u0130N \u00d6N Y\u00dcKLEME Y\u00d6NTEM\u0130<br \/>\n<b>Name \/ \u0130sim:<\/b>\u00a0Ye\u015filmurat, Serdar<br \/>\n<b>Degree \/ Derece:<\/b>\u00a0M.S.<br \/>\n<b>Supervisor \/ Dan\u0131\u015fman:<\/b>\u00a0Assoc. Prof. Dr. Veysi ISLER<br \/>\n<b>Cosupervisor \/ Ortak Dan\u0131\u015fman:<\/b>\u00a0&#8211;<br \/>\n<b>Department \/ B\u00f6l\u00fcm:<\/b>\u00a0Computer Engineering (CENG)<br \/>\n<b>Date \/ Tarih:<\/b>\u00a0February 2010<\/p>\n<p><b>Abstract:<\/b><br \/>\nA Web GIS system has a major issue of serving the map data to the client applications. Since most of the GIS services provide their geospatial data as basic image formats like PNG and JPEG, constructing those images and transferring them over the internet are costly operations. To enhance this inefficient process, various approaches are offered. Caching the responses of the requests on the client side is the most commonly implemented solution. However, this method is not adequate by itself. Besides caching the responses, predicting the next possible requests of the client and updating the cache with the responses for those requests provide a remarkable performance improvement. This procedure is called \u201cprefetching\u201d. Via prefetching, caching mechanisms can be used more effectively and efficiently. This study proposes a prefetching algorithm called Retrospective Adaptive Prefetch (RAP). The algorithm is constructed over a heuristic method that takes the former actions of the user into consideration. This method reduces the user-perceived response time and improves users\u2019 navigation efficiency. The caching mechanism developed takes the memory capacity of the client machine into consideration to adjust the cache capacity by default. Otherwise, cache size can be configured manually. RAP is compared with 4 other methods. According to the experiments, this study shows that RAP provides better performance enhancements than the other compared methods.<\/p>\n<p><b>\u00d6z:<\/b><br \/>\nWeb CBS uygulamalar\u0131 i\u00e7in harita verilerini istemci uygulamalar\u0131na sunmak \u00e7ok \u00f6nemli bir sorun te\u015fkil etmektedir. Bir\u00e7ok CBS servisi co\u011frafi verilerini PNG ve JPEG gibi temel resim formatlar\u0131nda sa\u011flad\u0131klar\u0131ndan dolay\u0131 bu resimleri \u00fcretmek ve internet \u00fczerinden iletmek maliyetli i\u015flemlerdir. Bu rand\u0131mans\u0131z s\u00fcreci iyile\u015ftirmek i\u00e7in \u00e7e\u015fitli \u00e7\u00f6z\u00fcm \u00f6nerileri sunulmu\u015ftur. Kullan\u0131c\u0131 isteklerine verilen cevaplar\u0131 istemci taraf\u0131nda saklamak (\u00f6nbelle\u011fe almak) en yayg\u0131n \u00e7\u00f6z\u00fcm olarak kar\u015f\u0131m\u0131za \u00e7\u0131kmaktad\u0131r. Ancak, bu y\u00f6ntem de tek ba\u015f\u0131na yeterli de\u011fildir. Verilen cevaplar\u0131 saklaman\u0131n yan\u0131nda bu yan\u0131tlar\u0131 kullanarak sonraki olas\u0131 istekleri tahmin edebilmek ve \u00f6nbelle\u011fi bu isteklerin cevaplar\u0131 ile g\u00fcncellemek kayda de\u011fer bir performans iyile\u015ftirmesi sa\u011flayacakt\u0131r. Bu y\u00f6nteme \u201c\u00f6ny\u00fckleme\u201d denilmektedir. \u00d6ny\u00fckleme sayesinde \u00f6nbellekte saklama mekanizmalar\u0131 daha etkili ve verimli bir \u015fekilde kullanabilmektedir. Bu \u00e7al\u0131\u015fma kullan\u0131c\u0131n\u0131n \u00f6nceki i\u015flemlerini dikkate alan deneyimsel bir y\u00f6ntem \u00fczerine kurulu bir \u00f6ny\u00fckleme algoritmas\u0131 \u00f6nermektedir. Bu y\u00f6ntem uygulaman\u0131n kullan\u0131c\u0131 isteklerine verdi\u011fi tepki s\u00fcresini azaltmakta ve kullan\u0131c\u0131n\u0131n harita \u00fczerinde gezinmesini daha etkin hale getirmektedir. Geli\u015ftirilen mekanizma \u00f6nbelle\u011fin boyutunu (elle ayarlanabilir olmakla beraber) varsay\u0131lan olarak istemci makinesinin belle\u011fini dikkate alarak ayarlamaktad\u0131r. \u00d6nerilen algoritma 4 farkl\u0131 metod ile kar\u015f\u0131la\u015ft\u0131r\u0131ld\u0131. Deneylerin sonucuna g\u00f6re bu \u00e7al\u0131\u015fmada sunulan metodun di\u011fer y\u00f6ntemlere g\u00f6re daha iyi performans sa\u011flad\u0131\u011f\u0131 g\u00f6r\u00fclmektedir.<\/p>\n<p>&nbsp;<\/p>\n<\/article>\n<\/section>\n<\/section>\n<\/section>\n","protected":false},"excerpt":{"rendered":"<p>In Progress Ph.D. Safak Cevikbas, METU, CENG, 2008- Sercan Pekin, METU, II, 2012- \u00d6zlem G\u00fcr, B\u0130LKENT, CS, 2014- M.Sc. Semih Kek\u00fcl, METU, GATE Ayla Kara \u00c7oban, METU, GATE Murat \u00c7elik, METU, GATE Completed Ph.D. Mehmet Fatih Uluat, METU, CENG, 2008-2014. Gokce Yildirim Kalkan, Efficient Rendering of Complex Scenes on Heterrogeneous \u2026 <a class=\"continue-reading-link\" href=\"https:\/\/blog.metu.edu.tr\/veysi\/research\/master-or-ph-d-theses-supervised\/\"> Continue reading <span class=\"meta-nav\">&rarr; <\/span><\/a><\/p>\n","protected":false},"author":1886,"featured_media":0,"parent":9,"menu_order":1,"comment_status":"open","ping_status":"open","template":"","meta":{"footnotes":"","_links_to":"","_links_to_target":""},"class_list":["post-20","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/blog.metu.edu.tr\/veysi\/wp-json\/wp\/v2\/pages\/20","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.metu.edu.tr\/veysi\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/blog.metu.edu.tr\/veysi\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/blog.metu.edu.tr\/veysi\/wp-json\/wp\/v2\/users\/1886"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.metu.edu.tr\/veysi\/wp-json\/wp\/v2\/comments?post=20"}],"version-history":[{"count":0,"href":"https:\/\/blog.metu.edu.tr\/veysi\/wp-json\/wp\/v2\/pages\/20\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/blog.metu.edu.tr\/veysi\/wp-json\/wp\/v2\/pages\/9"}],"wp:attachment":[{"href":"https:\/\/blog.metu.edu.tr\/veysi\/wp-json\/wp\/v2\/media?parent=20"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}