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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.
171

Simulation Of Depleted Gas Reservoir For Underground Gas Storage

Ozturk, Bulent 01 December 2004 (has links) (PDF)
For a natural gas importing country, &ldquo / take or pay&rdquo / approach creates problems since the demand for natural gas varies during the year and the excess amount of natural gas should be stored. In this study, an underground gas storage project is evaluated in a depleted gas Field M. After gathering all necessary reservoir, fluid, production and pressure data, the data were adapted to computer language, which was used in a commercial simulator software (IMEX) that is the CMG&rsquo / s (Computer Modelling Group) new generation adoptive simulator, to reach the history matching. The history matching which consists of the 4 year of production of the gas reservoir is the first step of this study. The simulation program was able to accomplish a good history match with the given parameters of the reservoir. Using the history match as a base, five different scenarios were created and forecast the injection and withdrawal performance of the reservoir. These scenarios includes 5 newly drilled horizontal wells which were used in combinations with the existing wells. With a predetermined injection rate of 13 MMcf/D was set for all the wells and among the 5 scenarios, 5 horizontal &ndash / 6 vertical injectors &amp / 5 horizontal - 6 vertical producers is the most successful in handling the gas inventory and the time it takes for a gas injection and production period. After the determination of the well configuration, the optimum injection rate for the entire field was obtained and found to be 130 MMcf/D by running different injection rates for all wells and then for only horizontal wells different injection rates were applied with a constant injection rate of 130 MMcf/d for vertical wells. Then it has been found that it is better to apply the 5th scenario which includes 5 horizontal &ndash / 6 vertical injectors &amp / 5 horizontal - 6 vertical producers having an injection rate of 130 MMcf/d for horizontal and vertical wells. Since within the 5th scenario, changing the injection rate to 1.3 Bcf/d and 13 Bcf/d, did not effect and change the average reservoir pressure significantly, it is best to carry out the project with the optimum injection rate which is 130 MMcf/d. The total gas produced untill 2012 is 394 BCF and the gas injected is 340 BCF where the maximum average reservoir pressure was recovered and set into a new value of 1881 psi by injection and cushion gas pressure as 1371 psi by withdrawal. If 5th scenario is compared with the others, there is an increase in injection and production performance about 90%.
172

Legal Framework Comparison Of Public Procurement Law With State Procurement Law

Yuksek, Murat 01 January 2005 (has links) (PDF)
This thesis makes the comparison of legal frameworks of the two Procurement Laws, the New Public Procurement Law (4734) and the Ex-State Procurement Law (2886) respectively. As a result of this comparison, it is seen that a lot of provisions starting from tender notice time limits to the awarding of contracts, have been changed substantially by the introduction of Turkish Public Procurement Law. Besides this comparison, the related procurement directive on construction works in European Community, namely EEC 93/37 is analyzed through the topics pertinent to the New Public Procurement Law, from which it is observed that there are both similar and different application regarding tender process in this directive when compared with the provisions of Turkish Public Procurement Law on construction works. This thesis study also aims to put forward the conception of Turkish contractors about the New Public Procurement Law by means of a questionnaire containing 15 questions. From the results of questionnaire, it is seen that majority of the contracting companies have a positive attitude towards the New Public Procurement Law although some provisions of the Law do not meet the expectations of the companies.
173

Development Of Masonry House Wall Strengthening Techniques Against Earthquakes Using Scrap Tires

Golalmis, Mustafa - 01 July 2005 (has links) (PDF)
About half of the building stock in Turkey is masonry type and one fourth of the building stock is one-storey brick type masonry buildings. Especially the rural masonry houses are commonly constructed by their own residents without any engineering knowledge. Traditional masonry houses usually have heavy roofs which generate large lateral forces on walls during earthquakes. Readily available retrofitting techniques are mostly complicated and costly making it not feasible for uneducated poor residents to strengthen their own houses. The aim of this thesis is to develop a new alternative strengthening technique using scrap tires that is economic and easy to apply on the walls of one-story masonry houses. In order to investigate the usage of scrap tires for masonry wall post-tensioning, forty three scrap tire rings (STRs) from nine different brands and nine rim-rings direct tension experiments were conducted. The average tensile load capacities of STRs and rim-rings were found as 132.6 kN and 53 kN, respectively. Six strip walls (i.e., four brick- and two briquette-walls) strengthened by applying post-tensioning loads with STCs and hybrid system were tested in out-of-plane bending direction. The out-of-plane capacity of the brick and briquette walls increased up to about 9 times and 5 times with respect to their nominal capacities, respectively. Finally, two-full scale traditional masonries were tested by the tilting table. The capacity of strengthened house increased 75% with respect to the unstrengthened one. The results obtained form the conducted tests are highly promising and suggest that the method can be used as a low-cost and simple strengthening technique for seismically deficient single storey, masonry type houses.
174

Exhaustion Of Industrial Property Rights In The European Union And Its Implications On The Application Of This Principle In Turkey

Tutkun, Secil 01 December 2005 (has links) (PDF)
This thesis analyzes the reconciliation of industrial property rights with the principle of free movement of goods in the EU and the implications of this solution on trade relations between the EU and Turkey in the scope of the Decision No. 1/95 of the EC-Turkey Association Council. In the second chapter, patents, trademarks, industrial designs and utility models then the EU regulations and the international regulations concerning the protection of the relevant right in the EU region is examined. Although, the need for &ldquo / EU wide protection of industrial property rights&rdquo / is not covered by these regulations, there are special provisions which stipulate &ldquo / regional exhaustion&rdquo / for trademarks and industrial designs. In the EU region there are systems for granting Community Trademark and granting Community Industrial Design which are co-exist with the national systems. However there is no system for granting Community Patent or Community Utility Models and there is no special provision which determine the geographical boundary of the exhaustion of patents and utility models. Nevertheless, the principle of regional exhaustion was accepted through ECJ decisions long before the above mentioned regulations which are very recent. In the third chapter of the thesis, firstly the provisions of the Rome Treaty regarding the free movement of goods, then the process that ECJ had faced until the regional exhaustion doctrine was reached and the implementation clauses of this doctrine is examined. Implementation of this doctrine affects both the trade relations among EU Member States and the trade relations between Member States and the non-EU countries. In the fourth chapter of the thesis, the provisions of the Decision No. 1/95 which regulates the free movements of goods between Turkey and the EU are examined with the articles of national legislation concerning the exhaustion of industrial property rights in Turkey. By considering above mentioned provisions and the different views in the doctrine, the trade relation between the EU and Turkey is examined with the economical, political and legal aspects.
175

Preparation Of Plzt Thin Films By Chemical Solution Deposition And Their Characterization

Kaplan, Burkan 01 December 2005 (has links) (PDF)
ABSTRACT PREPARATION OF PLZT THIN FILMS BY CHEMICAL SOLUTION DEPOSITION AND THEIR CHARACTERIZATION Kaplan, Burkan M.S., Department of Metallurgical and Materials Engineering Supervisor: Prof. Dr. Macit &Ouml / zenbaS November 2005, 125 pages In this study, La3+ was substituted into lead zirconate titanate (PZT) system by Pb1-xLax(ZryTi1-y)1-x/4O3 nominal stochiometry and it was processed via chemical solution deposition on (111)-Pt/Ti/SiO2/Si-(100) substrate.PLZT solutions were prepared by mixing two solutions, one of which was obtained by dissolving lead acetate and lanthanum acetate hydrate in 2 methoxyethanol at high temperature. This solution was then mixed with the second solution containing zirconium propoxide and titanium isopropoxide. 40ml/0.4M solution was prepared and spin coated on Pt/Ti/SiO2/Si substrates at 3000 rpm for 30 seconds. After 4 coating cycles, film thickness was reached to 600 nm. A systematic study was carried out in different regions of PLZT phase diagram tetragonal, rhombohedral and on the morphotropic phase boundry (MPB) to obtain optimized results of ferroelectric, dielectric and optical properties of the material. During the period of the work, effect of parameters on these properties such as heat treatment conditions, chemical composition of the film, microstructure and thickness of the film was investigated. The films were characterized structurally and electrically. For structural properties, X-ray diffraction technique (XRD), energy dispersive spectrometry (EDS) and Scanning Electron Microscope (SEM) were used to observe phases and surface characterization. For electrical measurements, ferroelectric tester was used to obtain dielectric constant, loss tangent and hysteresis curves. Optical transmittance of the films was also investigated by UV-VIS Spectrophotometer and optical film constants were calculated by modified envelope method. It was observed that the optimum heat treatment conditions were achieved at 7500C for 3 hours. The highest ferroelectric and dielectric properties such as remanent polarization and dielectric constant were obtained using that temperature. The dielectric constant of the films was measured in the frequency range of 1kHz-1MHz and remained almost constant in this region. The change of dielectric constant and ferroelectric hysteresis loops were obtained as a function of Zr/Ti ratio and La content. The grain size as a function of sintering temperature and La content was investigated. It was seen that as the sintering temperature was increased, the grain size of the films increased. The same tendency was also observed when the La content was increased. Fatigue behavior of PLZT thin films was also investigated by Radiant Ferroelectric Tester at 50 kHz and &plusmn / 15V. Change of remanent polarization (Pr) as a function of cumulative switching cycles (N) was drawn with the log scale of x-axis. Furthermore, leakage current characteristics of the films were also obtained by the ferroelectric tester at &amp / #61617 / 15V. It has been observed that as the La content of the film was increased, leakage current of the PLZT films decreased. Keywords: PLZT, (111)-Pt/Ti/SiO2/Si-(100) substrate, Chemical Solution Deposition.
176

Präventionsstudie Psychoanalytische Prävention für Familien mit Kindern im Alter von null bis drei Jahre

Henke, Bernd. Unknown Date (has links)
Universiẗat, Diss., 2007--Kassel.
177

Analysis of childhood diseases and malnutrition in developing countries of Africa /

Khatab, Khaled. January 2007 (has links)
Zugl.: München, University, Diss., 2007.
178

Kinder beobachten und erfassen - ein Kinderspiel? : Vergleichsstudie von Erzieherinnen und Praktikantinnen zur Rezeption des Sozialverhaltens von Kindern unter drei Jahren /

Marti Salzmann, Gabrielle. Strohm, Gabriele. January 2006 (has links) (PDF)
Zweite Studienarbeit Hochschule für Angewandte Psychologie Zürich, 2006.
179

Families of hypersurfaces with many prescribed singularities

Westenberger, Eric. Unknown Date (has links) (PDF)
Techn. University, Diss., 2004--Kaiserslautern.
180

Raman Studies of Conformational Energies and Hydrogen Bonding in Alcohols

Maleknia, Simindokht 08 1900 (has links)
The conformational energy differences have been determined for ethylene glycol, 2- chloroethanol, and 2,2- dichloroethanol in the neat liquid, DMSO, and H20 with Raman spectroscopy. Spectra in the 0-H valence region were utilized to determine the energy difference between interand intramolecularly hydrogen bonded species. It was found that the solvent effect on the relative stabilities of the gauche and trans rotamers of the alcohols differ significantly. The results also indicate that, unlike ethylene glycol, there is significant intramolecular hydrogen bond formation in the halogenated alcohols in the neat liquid phase. Stronger intramolecular hydrogen bond formation was observed in dichloroethanol than in 2-chloroethanol.

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