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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Design Decisions On Automobile Driver Interface With Regard To Subjective Evaluations Of Users

Altas, Aylin 01 December 2006 (has links) (PDF)
This study analyzes the users&rsquo / expectations from automobile interface in terms of their subjective assessments and middle class automotive design. The factors that affect the users&rsquo / impressions in both physical and psychological manner are presented. The importance of subjective users&rsquo / expectations and the issue of usability, which is handled from the traditional definition through the pleasure in use context, are discussed. The correlations between the physical appearance and psychological and behavioral responses are examined since the aesthetic properties affect the consumer satisfaction in both physically and psychologically. Automobile interface is identified under the considerations of user expectations. Factors that affect the drivers&rsquo / perception of interior and the decision making process are mentioned regarding with physical and psychological expectations of users. The case study is performed to clarify design criteria of the dashboards that belong to middle class segment under the consideration of Turkish drivers&rsquo / subjective evaluations. The study provides the chance of understanding the consumers&rsquo / attitudes toward the instrument panel elements through their design properties. This study examines and proposes Turkish users&rsquo / preferences and tastes in terms of physical and psychological expectations in the field of automobile interior design. It also provides techniques and results about users&rsquo / subjective evaluations that could be taken into account while designing an automobile belongs to a specific car segment with visual and functional properties of dashboard.
72

On The Avalanche Properties Of Misty1, Kasumi And Kasumi-r

Akleylek, Sedat 01 February 2008 (has links) (PDF)
The Global System for Mobile (GSM) Communication is the most widely used cellular technology. The privacy has been protected using some version of stream ciphers until the 3rd Generation of GSM. KASUMI, a block cipher, has been chosen as a standard algorithm in order to be used in 3rd Generation. In this thesis, s-boxes of KASUMI, MISTY1 (former version of KASUMI) and RIJNDAEL (the Advanced Encryption Standard) are evaluated according to their linear approximation tables, XOR table distributions and satisfaction of the strict avalanche criterion (SAC). Then, the nonlinear part, FI function, of KASUMI and MISTY1 are investigated for SAC. A new FI function is defined by replacing both s-boxes of KASUMI by RIJNDAEL&rsquo / s s-box. Calling this new version KASUMI-R, it is found to have an FI function significantly better than others. Finally, the randomness characteristics of the overall KASUMI-R for different rounds are compared to those of MISTY1 and KASUMI, in terms of avalanche weight distribution (AWD) and some statistical tests. The overall performance of the three ciphers is found to be same, although there is a significant difference in their FI functions.
73

Metadata Extraction From Text In Soccer Domain

Gokturk, Ozkan Ziya 01 September 2008 (has links) (PDF)
Video databases and content based retrieval in these databases have become popular with the improvements in technology. Metadata extraction techniques are used for providing data to video content. One popular metadata extraction technique for mul- timedia is information extraction from text. For some domains, it is possible to &amp / #64257 / nd accompanying text with the video, such as soccer domain, movie domain and news domain. In this thesis, we present an approach of metadata extraction from match reports for soccer domain. The UEFA Cup and UEFA Champions League Match Reports are downloaded from the web site of UEFA by a web-crawler. These match reports are preprocessed by using regular expressions and then important events are extracted by using hand-written rules. In addition to hand-written rules, two di&amp / #64256 / erent machine learning techniques are applied on match corpus to learn event patterns and automatically extract match events. Extracted events are saved in an MPEG-7 &amp / #64257 / le. A user interface is implemented to query the events in the MPEG-7 match corpus and view the corresponding video segments.
74

Perception Values Of Local Users For Urban Identity Elements In Ankara Ataturk Boulevard

Abaci, Ezgi 01 March 2009 (has links) (PDF)
There are many components which define and complete the urban spaces. One of these components is urban equipment which responds to the needs of the dweller by serving different purposes and creates a link between urban life and public life style. Urban equipment not only enables the interaction between urban spaces and the users of these places, but also has an efficient role in defining the cities&rsquo / quality and &ldquo / identity&rdquo / . Ankara, as the capital city of the Turkish Republic, has had an important mission throughout its history. But although it is the first planned city of the Turkish Republic, Ankara has become a victim of modernization and rapid and unplanned urbanization. As a result of this situation Ankara started to lose its own values. The main purpose of this thesis is, to identify the roles of urban equipment as a visual image, based on the perception of environmental spaces and creating urban identity. The methodology in this thesis is firstly determining the urban equipment on Atat&uuml / rk Boulevard which lies between Ulus and Kugulu Park which is the center line of Ankara and then questioning their effects on the urban identity. For this reason a questionnaire is applied to the local users and then according to this questionnaire&rsquo / s results, urban equipment&rsquo / s values as an urban identity element are analyzed. As a result of this study, urban equipments on Atat&uuml / rk Boulevard and their positive and negative values are determined. Therefore, how they are perceived by the local users and their contribution to the spatial and urban identity is determined.
75

Plannig Methods For Guiding Urban Regeneration Processes In High-risk Areas

Eser, Nermin 01 April 2009 (has links) (PDF)
Cities in Turkey are great risk pools. Underqualified building stocks are the major components of such risk pools. For the mitigation of risks, &#039 / engineering approach offers retrofitting of individual buildings as an ultimate method. However, this proposition has economic and legal difficulties. Instead, it is essential to develop new policies to focus on areas of high earthquake risk as comprehensive urban regeneration activities. This new policy requires new tools to monitor urban regeneration processes. It is obligatory to make comprehensive plans for high risk areas and to take low income groups into consideration in mitigation action plans. Comprehensive regeneration in existing districts could provide means and standards of safety not necessarily maintained by the retrofitting of individual buildings. Potentials of regeneration processes are readily observed and practiced in Turkey as means of regulating urban regeneration processes, even if for purposes other than safety. Analysis of a set of regeneration projects selected from world experience indicates that current regeneration practice in Turkey is far from a comprehensive approach. Municipalities are fully empowered to designate regeneration areas and carry out redevelopment activities often providing increased dentsities on compensate for the costs. This has been reinstated in the new draft law. Rather than a separate law, general regulation of regeneration could be accommodated in the Development Law 3194. A special Law concerning regeneration could instead focus only on risk reduction issues in cities throughout Turkey. The identification of priorities for such regeneration processes could be made by the Ministry of Public Works and Settlement as the central authority, clarifying the scale and timing of each project. The implementation tools of urban regeneration and issues like authorization, responsibility, funding, and auditing could be determined in this special law. A new approach for urban regeneration is needed to describe organizational, participatory, financial framework.
76

Impact Of Passanger Comfort Level On Design Of Short-span Composite Steel I-girder High Speed Railroad Bridges

Senturk, Tolga 01 January 2010 (has links) (PDF)
In globalizing world, increase in demand for high speed rail travel requires comfortable ride over bridges while maintaining an economical design. These bridges either have composite steel I-girders, prestressed precast I or box girder superstructures. The span lengths can reach up to 40 meters. If frequency of wheel load pass at a point on bridge matches with one the critical frequencies of the structure, excessive vibration can developed both at the train and the bridge even if the structure is structurally safe. Excessive vibration can discomfort the passengers. Focus of this study is given to identify certain thresholds for the rigidity of span to minimize the passenger discomfort at short-span composite steel I-girder high speed railroad bridges. In this context, various span lengths with different girder configurations have been analyzed under various train design speeds and ballast stiffness. Eigenvalue analyses are performed to determine critical frequencies of bridges. Moving force models are used to determine structural vibrations as recommended by high speed railroad bridge design specifications. It is well-known that stiffer structures can have significantly less vibration amplitudes than lighter ones providing a comfortable ride for high speed train passes.
77

Evaluation Of State Owned Indigenous Coal Fired Power Plants Including Coal Reserves

Guler, Mehmet 01 February 2010 (has links) (PDF)
Fossil fuels has preserved their importance in gradually increasing production and consumption of both energy and electricity of the world. Asia, especially China and India, has arisen new actors of the sector. Energy and electricity consumption of Turkey has also increased in parallel with her economic development, but due to her limited resources, she has become more and more energy dependent in order to meet her growing demand. Although hard coal is only found around Zonguldak region, with its abundant and widely spread reserves, Turkey ranked world&rsquo / s third place in lignite production in 2008. Having low calorific value together with high ash and moisture content, most of lignites extracted is being consumed in thermic power plants located near those reserves. In the first two chapters of this study, energy in the world and Turkey will be considered seperately, then coal resources in Turkey will be analysed in the next coming chapter. Indirect and direct greenhouse emissions presented to the UNFCCC will be handled in the fifth chapter In the last chapter, first past and present performances of all indigenous coal fired power plants will be analysed, then after projecting their generation and fuel needs, they are evaluated considering with the reserves they are located. Finally, at the end of decomissioning of those power plants, remaining reserves will be re-evaluated and additional new units will be proposed accordingly.
78

Thermoelectric Cooling Of A Pulsed Mode 1064 Nm Diode Pumped Nd:yag Laser

Yuksel, Yuksel 01 December 2010 (has links) (PDF)
Since most of the energy input is converted to thermal energy in laser applications, the proper thermal management of laser systems is an important issue. Maintaining the laser diode and crystal temperature distributions in a narrow range during the operation is the most crucial requirement for the cooling of a laser system. In the present study, thermoelectric cooling (TEC) of a 1064 nm wavelength diode pumped laser source is investigated both experimentally and numerically. During the heat removal process, the thermal resistance through and between the materials, the proper integration of the TEC assembly, and the heat sink efficiency become important. For the aim of evaluating and further improving the system performance, various assembly configurations, highly conductive components, efficient interface materials and heat sink alternatives are considered. Several experiments are conducted during the system development stage, and parallel numerical simulations are performed both for comparison and also for providing valuable input for the system design. Results of the experiments and the simulations agree well with each other. As the laser device works in the transient regime, the experiments and the simulations are also implemented in this regime. In the final part of the study, the experiments are performed under the actual device working conditions. It is proved that with the designed TEC module and the copper heat sink system, the laser device can operate longer than the required operational time successfully.
79

X-ray And Optical Observations Of High Mass X-ray Binaries

Beklen, Elif 01 January 2010 (has links) (PDF)
In this thesis, X-ray and optical observations of accretion powered pulsars are presented. By using archival RXTE observations we work on the X-ray spectral and pulse timing analysis of 4U 1538-52, 4U 1907+09, SMC X-1 to have more detailed information about their orbital and spin parameters. For 4U 1538-52 and SMC X-1, we determined new orbital epochs. By using long term pulse history of 4U 1907+09, we were able to work spin-down trend of the system and also calculate the change in the spin-down rate. Using Fermi/GBM observations we can monitor bright accreting pulsar systems. We are producing long term histories of pulse frequency and flux of 20 continuosly monitoring systems. Adding Swift/BAT observations to GBM observations, for 4U 1626-67, we did reveal the characteristics belong to spin-down trend before and spin-up behaviour after torque reversal seen in 2008 February. Two newly discovered IGRJ06074+2205 and IGRJ01583+6713 sources are identified as X-ray binary systems and we found parameters of them like distance, magnitudes, by using both optical photometric and spectroscopic observations.
80

Adaptability Of Generative Algorithms: A Means To Sustaining The Dynamic Design Processes

Damdere, Ekin 01 September 2010 (has links) (PDF)
This thesis is an investigation focusing on the adaptability of generative systems in a dynamic design problem, where the problem definition changes according to the changing conditions of the environment and transforming needs of the architectural space. This thesis, instead of discussing the dynamicity of the design processes, investigates the use of an adaptable generative system in a case-specific dynamic design problem to sustain its changing problem definitions. The research mainly looks into the potentials of generative systems in terms of adaptability and develops a generative system that is able to transform its structure in accordance with the dynamic constraints of a complex design process.

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