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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.
241

Dna Repair Genes, Xrcc3 And Rad51, Polymorphisms And Risk Of Childhood Acute Lymphoblastic Leukemia

Tanrikut, Cihan 01 January 2011 (has links) (PDF)
In this study, the role of two DNA repair genes, X-ray repair cross complementing group 3 (XRCC3) Thr241Met and Rad51 G135C polymorphisms were investigated in the risk of development of childhood ALL in Turkish population among 193 healthy controls and 184 ALL patients, by using PCR-RFLP technique. For XRCC3 Thr241Met polymorphism, the frequencies of both heterozygous and homozygous mutant genotypes were found to be higher in the controls compared to ALL patients (OR: 0.59, p = 0.02 / OR: 0.48, p = 0.02, respectively). In addition, either heterozygous (Thr/Met) or homozygous mutant (Met/Met) genotypes were significantly more common in the controls than the ALL patients (OR: 0.55, p =0.005). In case of Rad51 G135C polymorphism, no significant associations have been found with the risk of childhood ALL. Combination of XRCC3 heterozygote and Rad51 heterozygote genotypes increased the protective effect for risk of childhood ALL. (OR=0.35 / p =0.02). Combination of homozygote mutant genotype of XRCC3 with homozygote wild type genotype of Rad51 gave a highly statistically proved protective effect for the development of disease (OR= 0.36 / p= 0.004). To our knowledge, this is the first study showing the protective role of XRCC3 Thr241Met polymorphism either alone or in combination with Rad51 G135C variant on the risk of development of childhood ALL. In addition, interactions of these polymorphisms with non-genetic risk factors were investigated. Only in terms of paternal exposure, the heterozygote (Thr/Met) genotype for XRCC3 gene in children whose father exposed to cigarette smoke demonstrated a significant risk of 3.0 fold (p=0.05). Moreover, the frequency of Rad51 135C allele was determined for the first time in Turkish population. The frequency of the mutant allele was found to be very similar to that observed in other Caucasian populations.
242

Space-time Discretization Of Optimal Control Of Burgers Equation Using Both Discretize-then-optimize And Optimize-then-discretize Approaches

Yilmaz, Fikriye Nuray 01 July 2011 (has links) (PDF)
Optimal control of PDEs has a crucial place in many parts of sciences and industry. Over the last decade, there have been a great deal in, especially, control problems of elliptic problems. Optimal control problems of Burgers equation that is as a simplifed model for turbulence and in shock waves were recently investigated both theoretically and numerically. In this thesis, we analyze the space-time simultaneous discretization of control problem for Burgers equation. In literature, there have been two approaches for discretization of optimization problems: optimize-then-discretize and discretize-then-optimize. In the first part, we follow optimize-then-discretize appoproach. It is shown that both distributed and boundary time dependent control problem can be transformed into an elliptic pde. Numerical results obtained with adaptive and non-adaptive elliptic solvers of COMSOL Multiphysics are presented for both the unconstrained and the control constrained cases. As for second part, we consider discretize-then-optimize approach. Discrete adjoint concept is covered. Optimality conditions, KKT-system, lead to a saadle point problem. We investigate the numerical treatment for the obtained saddle point system. Both direct solvers and iterative methods are considered. For iterative mehods, preconditioners are needed. The structures of preconditioners for both distributed and boundary control problems are covered. Additionally, an a priori error analysis for the distributed control problem is given. We present the numerical results at the end of each chapter.
243

ATRA inhibits ceramide kinase transcription through an ATRA-related transcription factor, COUP-TFI, in a human neuroblastoma cell line, SH-SY5Y

MURAKAMI, Masashi, 村上, 真史 25 March 2010 (has links)
名古屋大学博士学位論文 学位の種類:博士(医療技術学) (課程) 学位授与年月日 平成22年3月25日
244

IC Design and Implementation of 32-Bit 1.25 GHz Tree-Structured CLA Adder and Discrete Cosine Transform

Lee, Rong-Chin 14 June 2001 (has links)
The thesis comprises three parts: Part 1 is the design and implementation of a high speed pipelined carry lookahead adder (CLA) ; Part 2 introduces how to build 0.35£gm basic cell library in the Cadence 97¡¦s environment and execute the cell-based design flow by self-built basic cells; Part 3 is the design and implementation of a low-power discrete cosine transform (DCT) processor. Part 1 of this thesis is a 32-bit tree-structured pipelined carry lookahead adder (CLA) constructed by the modified all-N-transistor (ANT) design. Not only the CLA possesses few transistor count, but also occupies small chip size. Moreover, the post- layout simulation results given by TimeMill show that the clock used in the 32-bit CLA can run up to 1.25 GHz. The proposed architecture can be easily expanded for long data addition. Part 2 of this thesis is to describe the procedure of a self-built cell library in detail, and explain how to correctly proceed cell-based design flow by using the self-built basic cell library. Part 3 of this thesis is to implementation of a DCT processor. We carefully observed the operation behavior of Multiply Accumulator (MAC) and improved the power consumption
245

Competitive Strategy Analysis for The Copper Strip Industry in Taiwan

Wu, Eugene 09 July 2001 (has links)
This thesis uses case study, focus on four manufacturers in copper industry. Base on Porter¡¦s generic strategies ¡V Over all cost leadership, Focus, Differentiation, with diversification and joint venture, all together five competitive strategies as the foundations of investigate structure. And I have made the matrix chart and a survey base on the five administrative functions. I observe individually for four copper manufacturers¡¦ competitive strategies, which are approved by customers, to find out if each of them has had effect in the market. Finally, I use Michael E. Porter¡¦s competitive advantage to test the industry environment, mean while forecasting the coming 3-5 years of First Copper Technology Co., Ltd. base on the theories of SWOT and PEST as the following: 1. Having joint venture with copper manufacturers in Mainland China or East Europe to get products to compete with local manufacturers, and no longer produce low attach value products. 2. Combine Japanese or Korea wholesalers or set up a trading company to sell high attach value product in local areas in Japan and Korea. 3. Total output needs to be maintained by lowering the cost, but the products should be developed in high attach value categories like lead frame and other high level alloy products, to get alone with new developments.
246

The Study of All-optical Nonlinear Waveguide Devices

Tasy, Rong-Zhan 01 August 2003 (has links)
In the paper, the beam propagation method is used to analyze the characteristics and the applications of nonlinear optical waveguide structures. The nonlinear optical waveguide is a medium whose refractive index changes with the electric field intensity. Based on the mode theory, the propagating envelop of optical light waves in the three-layers nonlinear waveguide with the nonlinear cladding, the nonlinear substrate and the linear guiding film can be solved. Not only the dispersion relation curve is described, but also the affection of input power to the electric field distribution is observed. In the application of nonlinear optical waveguide structure, the three-layers nonlinear waveguide structure and the local nonlinear Mach-Zehnder waveguide interferometer structure will be discussed: In the three-layers nonlinear waveguide structure, by launching the symmetric and antisymmetric modes, various characteristics of spatial optical solitons will be observed. Based on the interaction property between spatial optical solitons, a new all-optical 1¡ÑN switching device will be proposed; In the local nonlinear Mach-Zehnder waveguide interferometer structure, by fixing the input signal power and changing the control power, output signal beam will show the switching property. Besides, by changing the local nonlinear distributions, the nonlinear Mach-Zehnder interferometer will show various logic functions. The numerical results show that the proposed structures could function as all-optical switch devices and all-optical logic gates.
247

The Development of China's Information Warfare and It Impact on Taiwan's National Defense

Chou, Fang-Yi 09 February 2009 (has links)
In 1991 Persian Gulf war US has used the innumerable high-tech weapons, not only wins Iraq, but also lets various countries broaden the outlook.Thus it urges various countries military national defense to present the revolutionary change.The massive information technology skill is utilized at the military war, by the information military national defense concept primarily, launched rapidly. Receiveing this military revolution as well as the economic growth and the high-tech industry's rapidly expanding. The PLA starts to impel that it constructs the information troops and develops high-tech weapons systm including space technology. The PLA uses the information warfare to enter each kind of information attack, affect government's effective operation and the society stable without the world consensus pressure. It could relieve Taiwan rapidly and achieves it¡¦s political and the military purpose before other country military interference. This research's discovery is that compareing with mainland China, Taiwan is a highly information society. Facing the PLA¡¦s information menace, we should grasp the information superiority , strengthen the protection work, promot modernization armament, maintain the defense capability effectively and national information security by the outstanding information ability. In oder to achieve the prevention of war and the defense goal, now providing the following suggestion¡G 1¡BSelecting the outstanding talent and promoting the national troops quality. 2¡BExpaning crosswise Military organization and storing up the information defense ability. 3¡BEstablishing information strategy instruction and strengthening all the people defense education. 4¡BConstructing the information security system and establishing the information infrastructure. 5¡BStrengthening the information psychological warfare, the law warfare, sedan chair controversy. 6¡BUsing the folk technical force strengthens national defense whole.
248

Design and Analysis of an All-optical Free-space Communication Link

Levander, Fredrik, Sakari, Per January 2002 (has links)
<p>Free Space Optics (FSO) has received a great deal of attention lately both in the military and civilian information society due to its potentially high capacity, rapid deployment, portability and high security from deception and jamming. The main issue is that severe weather can have a detrimental impact on the performance, which may result in an inadequate availability. </p><p>This report contains a feasibility study for an all-optical free-space link intended for short-range communication (200-500 m). Laboratory tests have been performed to evaluate the link design. Field tests were made to investigate availability and error performance under the influence of different weather conditions. Atmospheric impact due to turbulence related effects have been studied in detail. The most crucial part of the link design turned out to be the receiver optics and several design solutions were investigated. The main advantage of an all-optical design, compared to commercially available electrooptical FSO-systems, is the potentially lower cost.</p>
249

Literary radicalism in India : gender, nation and the transition to independence /

Gopal, Priyamvada, January 2005 (has links)
Texte remanié de: Th. Ph. D.--Ithaca, N.Y.--Cornell university. / Bibliogr. p. 167-173. Index.
250

Topics in sustainable transportation : opportunities for long-term plug-in electric vehicle use and non-motorized travel / Opportunities for long-term plug-in electric vehicle use and non-motorized travel

Khan, Mobashwir 25 June 2012 (has links)
In the first part of this thesis, GPS data for a year's worth of travel by 255 Seattle households is used to illuminate how plug-in electric vehicles (PEVs) can match household needs. Data from all vehicles in each of these households were analyzed at a disaggregate level primarily to determine whether each household would be able to adopt various types of PEVs without significant issues in meeting travel needs. The results suggest that a battery-electric vehicle (BEV) with 100 miles of all-electric range (AER) should meet the needs of 50% of Seattle's one-vehicle households and the needs of 80% of the multiple-vehicle households, when households charge just once a day and rely on another vehicle or mode just 4 days a year. Moreover, the average one-vehicle Seattle household uses each vehicle 23 miles per day and should be able to electrify close to 80% of its miles, while meeting all its travel needs, using a plug-in hybrid electric vehicle with 40-mile all-electric-range (PHEV40). Households owning two or more vehicles can electrify 50 to 70% of their total household miles using a PHEV40, depending on how they assign the vehicle across drivers each day. Cost comparisons between the average single-vehicle household owning a Chevrolet Cruze versus a Volt PHEV suggest that, when gas prices are $3.50 per gallon and electricity rates are 11.2 ct per kWh, the Volt will save the household $535 per year in energy/fuel costs. Similarly, the Toyota Prius PHEV will provide an annual savings of $538 per year over the Corolla. The results developed in this research provide valuable insights into the role of AER on PEV adoption feasibility and operating cost differences. The second part of this thesis uses detailed travel data from the Seattle metropolitan area to evaluate the effects of built-environment variables on the use of non-motorized (bike + walk) modes of transport. Several model specifications are used to understand and explain non-motorized travel behavior in terms of household, person and built-environment variables. Land-use measures like land-use mix, density, and accessibility indices were also created and incorporated as covariates to appreciate their marginal effects. The models include a count model for household vehicle ownership levels, a binary choice model for the decision to stay within versus departing one's origin zone (i.e., intra- versus inter-zonal trip-making), discrete choice models for destination choices and mode choices, and a zero-inflated negative binomial model for non-motorized trip counts per household. The mode and destination choice models were estimated separately for interzonal and intrazonal trips and for each of three different trip types (home-based work, home-based non-work, and non-home-based), to recognize the distinct behaviors at play when making shorter versus longer trips and different types of trips. This comprehensive set of models highlights how built-environment variables -- like the number and type of intersections present around one's origin and destination, the number of bus stops available within a certain radius, household and jobs densities, parking prices, land use mixing, and walk-based accessibility -- can significantly shape the pattern of one's non-motorized movement. The results underscore the importance of street connectivity (quantified as the number of 3-way and 4-way intersections in a half-mile radius), higher bus stop density, and greater non-motorized access in promoting lower vehicle ownership levels (after controlling for household size, income, neighborhood density and so forth), higher rates of non-motorized trip generation (per day), and higher likelihoods of non-motorized mode choices. Destination choices are also important for mode choices, and local trips lend themselves to more non-motorized options than more distance trips. Intrazonal trip likelihoods rose with higher street connectivity, transit availability, and land use mixing. For example, the results suggest that an increase in the land-use mix index by 10% would increase the probability of choosing to travel within the zone by 12%. As expected destinations with greater population and job numbers (attraction), located closer (to a trip's origin), offering lower parking prices and greater transit availability, were more popular. Interestingly, those with more dead ends (or cul de sacs) attracted fewer trips. Among all built environment variables tested, street structure offered the greatest predictive benefits, alongside jobs and population (densities and counts). For example, a 1-percent increase in the average number of 4-way intersections within a quarter-mile radius of the sampled households is estimated to increase the average household's non-motorized trip generation by 0.36%. A one-standard-deviation increase in the (mean) number of 4-way intersections at the average trip origin is estimated to increase the probabilities of bike and walk modes for interzonal home-based-work trips by 57% and 30%, respectively. In contrast, increasing the number of dead-ends at the origin by one standard deviation is estimated to decrease the probability of biking for both home-based-work and non-work trips by ~30%. These results underscore the importance of network density and connectivity for promoting non-motorized activity. The regional non-motorized travel (NMT) accessibility index ( derived from the logsum of a destination choice model) also offers strong predictive value, with NMT counts rising by by 7% following a 1% increase in this variable -- if the drive alone accessibility index is held constant (along with all other variables, evaluated at their means). Similarly, household vehicle ownership is expected to fall by 0.36% with each percentage point increase in the NMT accessibility index, and walk probabilities rise by 26.9% following a one standard deviation increase in this index at the destination zone. A traveler's socio-economic attributes also have important impacts on NMT choices, with demographics typically serving as much stronger predictors of NMT choices than the built environment. For example, the elasticity of NMT trip generation with respect to a household's vehicle ownership count is estimated to be -0.52. Males and tose with drivers licenses are estimated to have 17% and 39% lower probabilities, respectively, of staying within their origin zone, relative to women and unlicensed adults (ceteris paribus). Non-motorized model choices also exhibit strong sensitivity to age and gender settings. Several of the regional variables developed in this work, and then used in the predictive models, are highly correlated. For example, bus stop and intersection densities are very high in job- and population-dense areas. For example, the correlation co-efficients between the bus stop density and 4-way intersection density is 0.805, between NMT and SOV AIs is 0.830 and between 4-way intersection density and NMT AI is 0.627. As a result, many variables are proxying for and/or competing with each other, as is common in models with many land use covariates, and it is difficult to quantify the exact impact of each of these variables. Nonetheless the models developed here provide valuable insight into the role of several new variables on non-motorized travel choices. Some final case study applications, moving all households to the downtown area (that has high accessibility indices and density), illustrate to what extent these revealed-data-based models will predict shifts toward and away from non-motorized trip-making. It appears that average household vehicle ownership level reduces to 0.57 from 1.89 (a 70% reduction) and average two-day NMT trip generation increases to 5.92 from 0.83 (an increase of more than 6 times). Such ranges are valuable to have in mind, when communities seek to reduce reliance on motorized travel by defining new built-environment contexts. / text

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