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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.
41

Vztah odpovědnosti za škodu a odpovědnosti za vady / The relationship between liability for damage and liability for defects

Rozinková, Lucie January 2013 (has links)
People encounter civil relationships in everyday life, thus the civil law follows a human being from his/her birth to death. Obligation relationships can arise not only at the basis of law actions, predominantly contracts, but also from illegal actions and by law qualified events, which lead to an origin of damages or a defect in an object of fulfilment. Both, liability for damage and liability for defects represent significant part of civil law and belong among the most discussed problems in law theory. The aim of this thesis is to focus on mutual relationship between liability for damage and liability for defects according to the Act No. 40/1964 LC., civil legal code, and to present important terms with a consideration of a rich judicature in this area. Some of the differences between liability for damage and liability for defects according to the Act No. 513/1991 LC. are explained briefly; since the commercial law modification would deserve a separate thesis. This thesis consists of six chapters which are further separated into individual subchapters. The first chapter is dedicated to the liability in general and its law- theoretical explanation and specification of the term civil liability. The second chapter called "Prevention of damages in civil relationships" tells about prevention of origin...
42

Structural integrity assessment of C-Mn pipeline steels exposed to sour environments

Holtam, Colum January 2010 (has links)
Oil and gas fields can contain significant amounts of hydrogen sulphide and the behaviour of C-Mn pipeline steels exposed to sour environments (i.e. those containing water and hydrogen sulphide) continues to be one of the most active areas of research in the oil and gas industry. This project is aimed at improving the procedures used to assess the significance of flaws in offshore pipelines and risers operating in such environments. Experimental work has focused on examining the behaviour of C-Mn pipeline steel in a sour environment with respect to both static and fatigue crack growth behaviour, for which there is a paucity of data. In particular, the critical influence of crack depth on the crack growth rate has been studied, in order to ensure that test methods and assessment procedures used in industry are appropriately conservative. Under cyclic loading conditions, an environmental crack depth effect has been demonstrated, whereby, shallow flaws appear to grow faster than deeper flaws at the same (low) value of ΔK. The observed behaviour is believed to be dominated by bulk hydrogen charging, i.e. hydrogen charging by absorption from the external surfaces of the specimen rather than at the crack tip, and a lower concentration of hydrogen exists in the centre of the specimen than at the edges. The novel data generated have been applied to real-life pipeline defect assessments to demonstrate the influence of the observed crack growth rate, with a view to developing an improved assessment method. Example engineering critical assessments have been performed for circumferential surface-breaking girth weld flaws located on the internal surface of a typical steel catenary riser, operating in a sour environment and subject to vortex induced vibration fatigue loads. Companies operating in the oil and gas sector will derive benefit from this research programme through the application of new validated test methods and the development of improved in-service assessment procedures.
43

Modeling the Defect Density of States of Disordered SiO2 Through Cathodoluminescence

Jensen, Amberly Evans 01 May 2014 (has links)
This study measures the electron-induced luminescence (cathodoluminescence) for various samples of fused silica. With a band gap of ~8.9 eV, visible and near-IR (NIR) luminescence occurs only if there are states (localized defect or trap states) within the forbidden band gap for electrons to occupy. A model is presented based on the electronic band structure and defect density of states—used to explain electron transport in highly disordered insulating materials—which has been extended to describe the relative cathodoluminescent intensity and spectral bands as a function of incident beam energy and current density, sample temperatures, and emitted photon wavelength. Tests were conducted on two types of disordered SiO2 samples, the first type containing two variations: (i) thin (~60 nm) coatings on reflective metal substrates, and (ii) ~80 μm thick bulk samples. Luminescence was measured using a visible range SLR CCD still camera, a VIS/NIR image-intensified video camera, a NIR video camera, and a UV/VIS spectrometer. Sample temperature was varied from ~295 K to 40 K. The results of these tests were fit with the proposed model using saturation dose rate and mean shallow trap energy as fitting parameters and are summarized below. First, each incident energy has a corresponding penetration depth, or range, which determines the fraction of energy absorbed in the material. In the thinner samples, the range exceeds the thickness of the sample; therefore, the intensity decreases with increasing energy. However, for the thicker samples, the range is less than the sample thickness and the intensity increases linearly with incident energy. Next, at low current densities, luminescent intensity is linearly proportional to incident current density through the dose rate. At very high current densities, saturation is observed. Finally, the overall luminescent intensity increased exponentially as T decreased, until reaching an optimum temperature, where it falls off to zero (as the model predicts). The spectra show four distinct bands of emitted photon wavelengths, corresponding to four distinct energy distributions of defect states within the band gap, each behaving differently with temperature. The response of each band to temperature is indicative of the extent to which it is filled.
44

The role of DNA methylation in the development of colorectal neoplasia

Wong, Justin Jong Leong, Medical Sciences, Faculty of Medicine, UNSW January 2008 (has links)
DNA methylation is increasingly recognised as a significant epigenetic event that may initiate and drive the process of neoplasia in humans. In the colon, DNA methylation of key genes is common in a subset of colorectal cancers. The extent to which DNA methylation at various genes contributes to initiation of colorectal neoplasms is less clear. This study sought to clarify the biological and clinicopathological significance of methylation of various genes in the development of sporadic and familial colorectal neoplasia. Quantitative methylation-specific PCR (qMSP) assays (capable of detecting down to a measureable proportion of 0.1% of the total input DNA) were developed to determine the presence of CpG methylation at a given gene. Methylation of MLH1-C was found in the apparently normal mucosa samples from seven of 104 (7%) of individuals with sporadic colorectal cancer (CRC) showing microsatellite instability (MSI). No methylation of MLH1-C was found in the biological samples of individuals with microsatellite stable (MSS) counterparts (n=131). MLH1-C methylation may be a field defect that predisposes to the development of sporadic colorectal neoplasia, particularly those demonstrating MSI. Methylation of three of five genes within the 3p22 region including AB002340, MLH1, ITGA9, PLCD1 and DLEC1 (regional 3p22 methylation) was found in 83% of sporadic MSI (n=86) and 12% of MSS cancers demonstrating BRAF V600E mutation (n=42). Regional 3p22 correlated strongly with CpG island methylator phenotype (CIMP), and other clinicopathological characteristics typical of CIMP. Thus, regional 3p22 methylation and CIMP may be overlapping phenomena. Regional 3p22 methylation and the BRAF V600E mutation were found in normal colonic mucosa of four individuals with sporadic MSI CRC, and these cases also had multiple synchronous serrated polyps. These molecular aberrancies may predispose some individuals to the development of metachronous serrated neoplasia. Germline epimutations of APC do not contribute towards the development of FAP, AFAP, or hyperplastic polyposis syndromes. However, APC methylation in normal colonic mucosa of these individuals may represent a field defect in the development of futher neoplasms. In conclusion, different patterns of DNA methylation in normal colonic mucosa may represent a field defect important in the development of different subtypes of colorectal neoplasia.
45

Towards a self-evolving software defect detection process

Yang, Ximin 15 August 2007
Software defect detection research typically focuses on individual inspection and testing techniques. However, to be effective in applying defect detection techniques, it is important to recognize when to use inspection techniques and when to use testing techniques. In addition, it is important to know when to deliver a product and use maintenance activities, such as trouble shooting and bug fixing, to address the remaining defects in the software.<p>To be more effective detecting software defects, not only should defect detection techniques be studied and compared, but the entire software defect detection process should be studied to give us a better idea of how it can be conducted, controlled, evaluated and improved.<p>This thesis presents a self-evolving software defect detection process (SEDD) that provides a systematic approach to software defect detection and guides us as to when inspection, testing or maintenance activities are best performed. The approach is self-evolving in that it is continuously improved by assessing the outcome of the defect detection techniques in comparison with historical data.<p>A software architecture and prototype implementation of the approach is also presented along with a case study that was conducted to validate the approach. Initial results of using the self-evolving defect detection approach are promising.
46

Towards a self-evolving software defect detection process

Yang, Ximin 15 August 2007 (has links)
Software defect detection research typically focuses on individual inspection and testing techniques. However, to be effective in applying defect detection techniques, it is important to recognize when to use inspection techniques and when to use testing techniques. In addition, it is important to know when to deliver a product and use maintenance activities, such as trouble shooting and bug fixing, to address the remaining defects in the software.<p>To be more effective detecting software defects, not only should defect detection techniques be studied and compared, but the entire software defect detection process should be studied to give us a better idea of how it can be conducted, controlled, evaluated and improved.<p>This thesis presents a self-evolving software defect detection process (SEDD) that provides a systematic approach to software defect detection and guides us as to when inspection, testing or maintenance activities are best performed. The approach is self-evolving in that it is continuously improved by assessing the outcome of the defect detection techniques in comparison with historical data.<p>A software architecture and prototype implementation of the approach is also presented along with a case study that was conducted to validate the approach. Initial results of using the self-evolving defect detection approach are promising.
47

Morphology study and defect analysis of encapsulated cholesteric LCD

Tseng, Heng-Yi 23 July 2012 (has links)
This thesis studies the reliability issues of encapsulated cholesteric LCD, and analyzes the defective pixel. Adjusting fabrication process parameters, we change the thickness of the buffer layer and absorption layer to explore the influence of different boundaries to CLC. It is found that the buffer layer can provide a good protection. When the buffer layer is getting thicker, the less the defective pixels appear, and the absorption layer cannot induce defect. The reflection band of the ITRI¡¦s encapsulated CLCs blue shifts to UV band and then become defective pixel. When CLCs exposed to the atmosphere with large area, the reflected color will be shifted. The shift of reflection band is due to CLC¡¦s inherent properties. Different kind of CLC has different properties, and we found the reflection band of ITRI¡¦s CLC is blue shift and the nematic E48 with chiral dopant R811 is red. Mixing different features of CLCs with appropriate proportion can reduce the color shift. In conclusion, mixing different characteristics CLCs with appropriate proportion and providing good protection to encapsulated CLC, we can reduce CLC¡¦s color shift and restrain the defective pixel.
48

Gene Dosage Analyses on Ventricular Septal Defect (VSD) Related to Loss of Heterozygosity (LOH) on Chromosome 22q11 Region

Wang, Tai-lai 07 July 2005 (has links)
To identify genes related to the heart developments, a total of 92 CHD families from Kaohsiung Veteran General Hospital, including 290 individuals with 95 affected, were genotyped in this study. Among these CHDs families, 54 were diagnosed as VSDs, accounted for 56.8% of all CHDs. Ten highly polymorphic markers, D22S420, D22S427, D22S1638, D22S941, D22S1648, D22S944, D22S1623, D22S264, D22S303 and D22S315, from centromere to the HSA22q telomere, covering HSA22q11 were genotyped by using a semi-quantitative fluorescent PCR. LOH at loci on 22q11 have been identified in 31 VSDs affected individuals. Candidate genes in HSA22q11 region was identified by bioinformatic methods firstly based on Ensembl (EMBL-EBI and the Sanger Institute), Genome browser (UCSU) and Map viewer (NCBI), and then FatiGO Data mining with Gene Ontology and Swiss-Prot annotations. In order to narrow down more specific cardiac development-related candidate genes within HSA22q11, TUBA8, DGCR2, DGCR14, CLTCL1, HIRA, TBX1 and GNB1L, from the centromere to telomere, were further subjected to dosage analyses by quantitative PCR. Results indicated the most frequent LOH region was localized on D22S1648. There are 48.3% and 38.7% of 31 VSDs patients with one copy deletion in TUBA8 and HIRA, respectively. Two VSDs patients were deleted in all seven candidate genes. Furthermore, there are one CAVC and one VSD patient were deleted in five consecutive genes, TUBA8, DGCR2, DGCR14, CLTCL1 and HIRA.
49

Clinical results of percutaneous closure of large secundum atrial septal defects in children using the Amplatzer septal occluder

Huang, Ta-Cheng 18 June 2007 (has links)
Background: We reviewed our experience using the Amplatzer septal occluder (AGA Medical, Golden Valley, MN) to close large, secundum-type atrial septal defects (ASDs) in children. Methods: Between June 2002 and December 2005, 52 patients (mean age 13.5 ¡Ó 8.7 years) underwent transcatheter closure of large (≥25 mm), secundum ASDs by using the Amplatzer septal occluder (ASO). Groups 1 and 2 included patients with a retroaortic rim of <5 mm (n = 39) or ≥5 mm(n = 13), respectively. All procedures were performed with general anesthesia and transesophageal echocardiographic guidance except for 10 patients, which involved local anesthesia and 3-dimensional transthoracic echocardiography. Successful device implantations, device sizes, approaches, complications, and closure rates were assessed. Results: Device implantation was successful in 50 patients (96.1%), with no difference between groups (95% vs 100%, P > 0.05). In 2 patients, implantation failed because of embolism or deployment failure. Devices were larger in group 1 than in group 2 (29.7 ¡Ó 3.9 vs 26.7 ¡Ó 3.0 mm, P =0.04). The right upper pulmonary-vein approach was more common in group 1 than in group 2 (P = .0001). Complications and closure rates did not differ between the groups (P > .05). Conclusions: Transcatheter closure of large, secundum ASD by using the ASO device was feasible, and complication rates were low. A deficient retroaortic rim did not preclude successful device implantation; however, a large device may be needed to close large ASD. Close long-term follow-up is necessary to determine the safety of transcatheter closure of large ASDs in children.
50

Study on the Optical Properties for InGaN/GaN Multilayer Quantum Well Structures

Wang, Kai-Hong 25 July 2003 (has links)
The thesis mainly probes into the effects that the structure below multi quantum layer as regards the efficiency of luminescence of blue light LED in the different number layers and make further comparison. In the article, the students separately make analysis and comparison to the single quantum well , five multi quantum wells , ten multi quantum wells and thirty multi quantum wells. And discovered that different number layers of quantum well will occur different Phase Separation and Strain in the film. So the article mainly focuses on : (1.)Phase Separation in various of quantum well, it occurs different In-rich reaction and (2.)Different Strain levels which occurs different dislocation reaction. The two mechanisms will be discussed in detail with the effects of luminescence reaction of LED. According to the results of experiment, We found that it is easier to form V-shape defects and dislocation with the increasing indium content. Under the high indium content, the density of In-rich will increase obviously and spread to the GaN barrier, then the original structure of quantum well will be destroyed and descend the efficacy of luminescence. In the thicker GaInN quantum well, it will induce larger energy of strain inside the film, So the defect density will increase due to release the strain energy. It was also discovered the intensity of luminescence descend after measuring by PL. When grow different number layers , it was discovered that higher quantum layer will produce the roughness surfaces when using AFM . So the higher quantum layers will make greater influence in the efficacy of luminescence. By experiment, we found that the five to ten quantim wells will have the better photo characteristic.

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