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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.
11

The Relationship of Speech Defects with the Personality Development of Elementary School Children

Garrish, Eunice January 1944 (has links)
The purpose of this study is to aid in the personal development of abnormal speech defective personalities by determining the effects of crippled speech upon certain individuals.
12

Combined Model of Lean Six Sigma and Work Method for a Peruvian Ammunition Manufacturing

Mego-Aranguri, Cristhian, Roque-Soriano, Maria, Carvallo-Munar, Edgardo, Salas-Castro, Rosa, Cardenas-Rengifo, Luis 30 September 2020 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / In the arms industry, quality is essential because its products are used for special purposes. Therefore, in production, the rate of defective products is low. This study proposes a model to reduce the number of defective products based on the combined use of the Six Sigma and work method tools. For the purposes of this study, the production process of the 7.62 mm ammunition was analyzed because it presents several issues that affect product quality. The current methods and procedures of the production process were analyzed to identify the root causes of the problem and to provide a solution. After implementing the model, defective products were reduced from 20% to 13.67%..
13

Intragenic elements support the transcription of defective HIV-1 proviruses

Kuniholm, Jeffrey 24 January 2023 (has links)
Human immunodeficiency virus-1 (HIV-1) establishes a persistent proviral reservoir by integrating into the genome of infected host cells. Current antiretroviral treatments (ART) do not target this persistent population of proviruses which include latently infected cells that upon treatment interruption can be reactivated to contribute to HIV-1 rebound. Deep sequencing of persistent HIV-1 proviruses has revealed that greater than 90% of integrated HIV-1 genomes are defective and unable to produce infectious virions. We hypothesized that intragenic elements in the HIV genome support transcription of aberrant HIV-1 RNAs from defective proviruses that lack long terminal repeats (LTRs). Using an intact provirus detection assay, I observed that resting CD4+ T cells and monocyte-derived macrophages (MDMs) are biased towards generating defective HIV-1 proviruses. Multiplex reverse transcription droplet digital polymerase chain reaction (RT-ddPCR) identified env and nef transcripts which lacked 5’ untranslated regions (UTR) in acutely infected CD4+ T cells and MDMs indicating transcripts are generated that do not utilize the promoter within the LTR. 5’UTR-deficient env transcripts were also identified in a cohort of people living with HIV-1 (PLWH) on ART, suggesting that these aberrant RNAs are produced in vivo. Using 5’ rapid amplification of cDNA ends (RACE), I mapped the start site of these transcripts within the Env gene. This region bound several cellular transcription factors and functioned as a transcriptional regulatory element that could support transcription and translation of downstream HIV-1 RNAs. Transient expression of an HIV-1 5’UTR deletion construct in HEK293T cells demonstrated that HIV-1 transcripts and proteins are still produced when the 5’UTR is absent. These studies provide mechanistic insights into how defective HIV-1 proviruses are persistently expressed to potentially drive inflammation in PLWH.
14

THE ROLE OF TOMBUSVIRUS REPLICASE PROTEINS AND RNA IN REPLICASE ASSEMBLY, REPLICATION AND RECOMBINATION

Panaviene, Zivile Sliesaraviciute 01 January 2004 (has links)
Tombusviruses are single, positive strand RNA viruses of plants, often associated with parasitic defective interfering (DI) RNAs. Two viral- coded gene products, namely p33 and p92, are required for tombusvirus replication. The overlapping domains of p33 and p92 contain an arginine/proline-rich (RPR) RNA binding motif. In this study, the role of RPR motif and viral RNA in tombusvirus replication and recombination, as well as involvement of viral RNA in tombusvirus replicase assembly was examined. Using site-directed mutagenesis I generated a series of RPR mutants of Cucumber necrosis tombusvirus (CNV). Analysis of RPR mutants defined that wild type RPR motif, especially two of the four arginines, were required for efficient RNA binding in vitro, for replication of tombusviruses, their associated DI RNAs, subgenomic (sg)RNA synthesis and DI RNA recombination in vivo. Experiments using a two-component tombusvirus replication system showed that RPR motif is critical for functions of both p33 and p92 in replication, but its role in these proteins might not be identical. Recombination studies using a novel tombusvirus three-component system revealed that mutations in RPR motif of p33 replicase protein resulted in an altered viral RNA recombination rate. Identified DI RNA recombinants were mostly imprecise, with recombination sites clustered around a replication enchancer and an additional putative cis-acting element that might facilitate the template switching events by the tombusvirus replicase. To study the role of RNA during the assembly of functional tombusvirus replicase, recombinant CNV replicase that showed similar properties to plant-derived CNV replicase was purified from Saccharomyces cerevisiae. When in addition to p33 and p92 proteins DI RNA was co-expressed in yeast cells, the isolated replicase activity was increased ~40 fold. Further studies defined RNA motifs within two short DI RNA regions that enhanced active CNV replicase formation. In summary, this study showed that the conserved RNA binding motif of the tombusvirus replicase proteins and viral RNA are involved in replicase assembly, viral RNA replication, subgenomic RNA synthesis and RNA recombination. This data shed new light on the complex roles of the viral elements in replication, and will help future studies aimed at interfering with viral infections.
15

Mathematical approach to channel codes with a diagonal matrix structure

Mitchell, David G. M. January 2009 (has links)
Digital communications have now become a fundamental part of modern society. In communications, channel coding is an effective way to reduce the information rate down to channel capacity so that the information can be transmitted reliably through the channel. This thesis is devoted to studying the mathematical theory and analysis of channel codes that possess a useful diagonal structure in the parity-check and generator matrices. The first aspect of these codes that is studied is the ability to describe the parity-check matrix of a code with sliding diagonal structure using polynomials. Using this framework, an efficient new method is proposed to obtain a generator matrix G from certain types of parity-check matrices with a so-called defective cyclic block structure. By the nature of this method, G can also be completely described by a polynomial, which leads to efficient encoder design using shift registers. In addition, there is no need for the matrices to be in systematic form, thus avoiding the need for Gaussian elimination. Following this work, we proceed to explore some of the properties of diagonally structured lowdensity parity-check (LDPC) convolutional codes. LDPC convolutional codes have been shown to be capable of achieving the same capacity-approaching performance as LDPC block codes with iterative message-passing decoding. The first crucial property studied is the minimum free distance of LDPC convolutional code ensembles, an important parameter contributing to the error-correcting capability of the code. Here, asymptotic methods are used to form lower bounds on the ratio of the free distance to constraint length for several ensembles of asymptotically good, protograph-based LDPC convolutional codes. Further, it is shown that this ratio of free distance to constraint length for such LDPC convolutional codes exceeds the ratio of minimum distance to block length for corresponding LDPC block codes. Another interesting property of these codes is the way in which the structure affects the performance in the infamous error floor (which occurs at high signal to noise ratio) of the bit error rate curve. It has been suggested that “near-codewords” may be a significant factor affecting decoding failures of LDPC codes over an additive white Gaussian noise (AWGN) channel. A near-codeword is a sequence that satisfies almost all of the check equations. These nearcodewords can be associated with so-called ‘trapping sets’ that exist in the Tanner graph of a code. In the final major contribution of the thesis, trapping sets of protograph-based LDPC convolutional codes are analysed. Here, asymptotic methods are used to calculate a lower bound for the trapping set growth rates for several ensembles of asymptotically good protograph-based LDPC convolutional codes. This value can be used to predict where the error floor will occur for these codes under iterative message-passing decoding.
16

Práva z vadného plnění ve spotřebitelských smlovách / Rights from defective performance in consumer contracts

Nováková, Kristýna January 2019 (has links)
1 Rights from defective performance in consumer contracts Abstract This diploma thesis deals with rights from defective performance in consumer contracts, with both the general regulation of the rights of defective performance in the contract between the entrepreneur and the consumer, as well as the specific rights of defective performance in this contract in the case of the purchase contract and contract for work. The thesis contains definitions of the basic subjects of consumer law, as well as legal terms, which are often associated with the application of legal rules of consumer law. Such terms are defective performance, as well as individual types of defects, or even the disputed warranty under the law or voluntary contractual guarantees provided by the seller. This thesis deals in detail with the rights of defective performance, which belongs to the buyer in case of conclusion of the purchase contract. A special focus is given to the special subsection of civil code on the sale of goods in the shop. The part of this thesis is also the definition of the term of complaint, the exercise of the right from defective performance in terms of its content, manner or form, or the work also represents the persons entitled or compulsory to complain. The thesis also solves problems with proper application of the...
17

Propuesta de mejora en el proceso de producción de tela en una empresa del rubro textil con metodología Lean Manufacturing / Proposal for improvement of production process fabric in a textile company with caption of lean manufacturing

Romero Sanchez, Jose Miguel Ernesto 09 1900 (has links)
En el presente estudio, tiene como objetivo reducir el alto índice de productos defectuosos, incrementando así los niveles de productividad en la empresa. Se explicarán los beneficios de la implementación de la metodología Lean Manufacturing en el proceso productivo textil en el área de tintorería y acabado de tela de la empresa TEXTIL SAN RAMÓN S.A. Por esta razón, se señala que si se implementa la metodología Lean Manufacturing, El trabajo está compuesto por tres capítulos. En el primer capítulo, se explica en qué consiste la metodología Lean Manufacturing. En el segundo capítulo, se presentará la situación actual de procesos actual de tintorería y acabado de tela. Asimismo, se describirá los principales beneficios de la implementación de la metodología Lean Manufacturing en el proceso de productivo textil, que buscará reducir el número de productos defectuosos en el proceso de tintorería y acabado de tela e incrementar los niveles de productividad de la empresa. Finalmente en el tercer capítulo se logra plasmar la implementación de esta metodología la cual resulta ser beneficiosa en el proceso de tintorería y acabado. Con estos resultados se evidencia que mediante la metodología Lean Manufacturing se puede reducir el índice de productos defectuosos significativamente, incrementando así en nivel de productividad, con el fin de reducir costos, aumentar la rentabilidad de la empresa y satisfacer las necesidades de los clientes. / In the present study, it aims to reduce the high rate of defective products, thus increasing productivity levels in the company. the benefits of implementing Lean Manufacturing in the textile production process in the area of fabric dyeing and finishing of textile SAN RAMON SA For this reason, it explained, noted that if the methodology is implemented Lean Manufacturing, The work is composed of three chapters. In the first chapter, it explains what Lean Manufacturing methodology. In the second chapter, the current situation of current processes dyeing and finishing fabric will be presented. Also, the main benefits of implementing Lean Manufacturing methodology will be described in the process of textile production, which seek to reduce the number of defective products in the process of dyeing and finishing fabric and increase the productivity levels of the company. Finally in the third chapter it manages to capture the implementation of this methodology which proves to be beneficial in the process of dyeing and finishing. With these results it is evident that through Lean Manufacturing methodology can significantly reduce the rate of defective products, increasing in level of productivity, in order to reduce costs, increase profitability and meet the needs of customers. / Trabajo de investigaciòn
18

Formal Methods For Verification Based Software Inspection

Powell, Daniel, n/a January 2003 (has links)
Useful processes, that are independently repeatable, are utilised in all branches of science and traditional engineering disciplines but seldom in software engineering. This is particularly so with processes used for detection and correction of defects in software systems. Code inspection, as introduced by Michael Fagan at IBM in the mid 1970's is widely recognised as an effective technique for finding defects in software. Despite its reputation, code inspection, as it is currently practiced, is not a strictly repeatable process. This is due to the problems faced by inspectors when they attempt to paraphrase the complicated semantics of a unit of computer code. Verification based software inspection, as advocated by the cleanroom software engineering community, requires that arguments of correctness be formulated with the code and its specification. These arguments rely on the reader being able to extract the semantics from the code. This thesis addresses the requirement for an independently repeatable, scalable and substantially automated method for yielding semantics from computer code in a complete, unambiguous and consistent manner in order to facilitate, and make repeatable, verification based code inspection. Current literature regarding the use of code inspection for verification of software is surveyed. Empirical studies are referenced, comparing inspection to software testing and program proof. Current uses of formal methods in software engineering will be discussed, with particular reference to formal method applications in verification. Forming the basis of the presented method is a systematic, and hence repeatable, approach to the derivation of program semantics. The theories and techniques proposed for deriving semantics from program code extend current algorithmic and heuristic techniques for deriving invariants. Additionally, the techniques introduced yield weaker forms of invariant information which are also useful for verification, defect detection and correction. Methods for using these weaker invariant forms, and tools to support these methods, are introduced. Algorithmic and heuristic techniques for investigating loop progress and termination are also introduced. Some of these techniques have been automated in supporting tools, and hence, the resulting defects can be repeatably identified. Throughout this thesis a strong emphasis is placed on describing implementable algorithms to realise the derivation techniques discussed. A number of these algorithms are implemented in a tool to support the application of the verification methods presented. The techniques and tools presented in this thesis are well suited, but not limited to, supporting rigorous methods of defect detection as well as formal and semi-formal reasoning of correctness. The automation of these techniques in tools to support practical, formal code reading and correctness argument will assist in addressing the needs of trusted component technologies and the general requirement for quality in software.
19

Placental Oxidative Stress in Preeclampsia

Vanderlelie, Jessica, n/a January 2006 (has links)
Affecting 6-8% of all pregnancies, preeclampsia is the leading cause of maternal morbidity in the western world and is charactensed by hypertension, proteinuria, edema and platelet aggregation. Despite its prevalence and severity, no comprehensive theory or single factor has been suggested to explain the pathophysiology of this multi system disorder of pregnancy, with the only therapies being bed rest, pharmacological symptom management and if necessary early delivery. Oxidative stress plays an important role in the pathophysiology of preeclampsia, resulting from defective trophoblast invasion, reductions in placental perfusion and placental hypoxia/reoxygenation. The inability of endogenous antioxidant systems up regulated in normal pregnancy, to control increased levels of oxidative stress, is suggested as a possible factor in the feed forward generation of reactive oxygen species and placental oxidative stress. That in turn may stimulate increased syncytiotrophoblast apoptosis, endothelial cell activation and the maternal hyper immune response characteristic of preeclampsia. Analysis of the research literature revealed that previous evaluations of placental oxidation and antioxidant enzyme activity in preeclampsia were by no means comprehensive, and exhibited significant inter-study variations. It was the aim of this thesis to clarify the placental oxidative state and the endogenous antioxidant activity of glutathione peroxidase, thioredoxin reductase, thioredoxin and superoxide dismutase in human placentae in an attempt to determine if variations in antioxidant function were due to changes in gene expression or protein oxidation. The findings reported in this thesis indicate the presence of increased levels of oxidative stress in the preeclamptic placenta, associated with significant reductions in antioxidant enzyme capacity. Quantitative real-time PCR analysis of placental samples revealed that deceases in antioxidant capacity in the placenta are more likely to be related to the significant oxidative burden within the tissue rather than reductions in gene expression. A number of animal models exist to investigate components of preeclampsia pathophysiology, however the ability of these models to mimic the oxidative and antioxidant features of preeclampsia remains unclear. The exposure of pregnant rats to N(G)-nitro-L-arginine methyl ester is a widely used model of endothelial cell dysfunction during preeclampsia. It was the aim of this thesis to determine the biochemical characteristics of this model in an attempt to assess its effectiveness in mimicking oxidative changes in the preeclamptic placenta. Although this model is capable of producing a syndiome in rats similar to the disorder in terms of physiology, this is not manifest in terms of placental biochemistry. The importance of selenium in the synthesis of selenobased antioxidants such as glutathione peroxidase and thioredoxin reductase is well documented. Increasing demand for selenium by the developing fetus may be linked to reductions in selenium status during pregnancy. Considering preeclampsia is associated with significant reductions in selenium status it may be hypothesised that reductions in antioxidant function may be linked to selenium inadequacy. The modulation of dietary selenium in pregnant rats was used to determine the importance of selenium during pregnancy and its effect on antioxidant function and placental oxidative stress. The results of this analysis revealed that selenium deficiency causes a pregnancy specific condition similar to preeclampsia. This condition was found to be associated with increased placental oxidative stress and significant reductions in the systemic activity of selenobased antioxidants that could be modified through selenium supplementation. In summary, data obtained in this thesis indicate that placental oxidative stress and reduced antioxidant enzyme activity play a significant role in the pathogenesis of preeclampsia. These studies support the hypothesis that antioxidant sufficiency is crucial in the maintenance of oxidative balance and that antioxidant dysfunction may result in damage to the placenta and the progression of the disease. These novel data further our understanding of the pathophysiology of preeclampsia and provide new insight into the pathogenesis of clinical complications exhibited in this condition, suggesting antioxidant therapy as a possible means for improving the health outcomes of both mother and baby.
20

An introduction to Gerber-Shiu analysis

Huynh, Mirabelle January 2011 (has links)
A valuable analytical tool to understand the event of ruin is a Gerber-Shiu discounted penalty function. It acts as a unified means of identifying ruin-related quantities which may help insurers understand their vulnerability ruin. This thesis provides an introduction to the basic concepts and common techniques used for the Gerber-Shiu analysis. Chapter 1 introduces the insurer's surplus process in the ordinary Sparre Andersen model. Defective renewal equations, the Dickson-Hipp transform, and Lundberg's fundamental equation are reviewed. Chapter 2 introduces the classical Gerber-Shiu discounted penalty function. Two framework equations are derived by conditioning on the first drop in surplus below its initial value, and by conditioning on the time and amount of the first claim. A detailed discussion is provided for each of these conditioning arguments. The classical Poisson model (where interclaim times are exponentially distributed) is then considered. We also consider when claim sizes are exponentially distributed. Chapter 3 introduces the Gerber-Shiu function in the delayed renewal model which allows the time until the first claim to be distributed differently than subsequent interclaim times. We determine a functional relationship between the Gerber-Shiu function in the ordinary Sparre Andersen model and the Gerber-Shiu function in the delayed model for a class of first interclaim time densities which includes the equilibrium density for the stationary renewal model, and the exponential density. To conclude, Chapter 4 introduces a generalized Gerber-Shiu function where the penalty function includes two additional random variables: the minimum surplus level before ruin, and the surplus immediately after the claim before the claim causing ruin. This generalized Gerber-Shiu function allows for the study of random variables which otherwise could not be studied using the classical definition of the function. Additionally, it is assumed that the size of a claim is dependant on the interclaim time that precedes it. As is done in Chapter 2, a detailed discussion of each of the two conditioning arguments is provided. Using the uniqueness property of Laplace transforms, the form of joint defective discounted densities of interest are determined. The classical Poisson model and the exponential claim size assumption is also revisited.

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