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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

Reproductive Soundness and Egg Quality in Chickens Selected for Low and High Antibody Response

Albrecht, Heather Nicole 08 September 2011 (has links)
For 36 generations, White Leghorn chickens were selected for high (HAS) or low (LAS) antibody response to sheep red blood cells. The focus of this thesis was to investigate correlated responses in reproductive soundness and egg quality resulting from that selection. Forty-five hens and 25 roosters from each antibody line were used. In hens, commencement and intensity of lay, and egg quality, were analyzed; in both sexes, length of fertility was considered. Hens and roosters were mated to an intercross line to avoid confounding selection with sex effects. The LAS line was more reproductively sound, commencing lay at a younger age (11.67 ± 3.53 d; P < 0.001), lighter body weight (-169.46 ± 40.20 g; P < 0.001) and with greater intensity (2.68 ± 0.25%; P = 0.001) than the HAS line. Additionally, the LAS line had a greater length of fertility (hens: 2.43 ± 0.55 d; P < 0.001; roosters: 3.11 ± 0.71 d; P < 0.001). In contrast to their poorer reproductive soundness, the HAS line had superior egg quality compared to the LAS line. Egg shape index (4.12 ± 0.55; P < 0.001) and albumen height, measured in both mm (0.27 ± 0.12 mm; P < 0.001) and Haugh units (1.89 ± 0.91; P = 0.04), were superior in HAS hens. Selection for increased antibody response appeared to compromise reproductive soundness, perhaps due to limitations in available resources. However, the selection did not compromise egg quality. / Master of Science
12

Uma metodologia baseada na lógica linear para análise de processos de workflow interorganizacionais

Passos, Lígia Maria Soares 22 February 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work formalizes four methods based on Linear Logic for the verification of interorganizational workflow processes modelled by Interorganizational Workflow nets, which are Petri nets that model such processes. The first method is related to the verification of the Soundness criteria for interorganizational workflow processes. The method is based on the construction and analysis of Linear Logic proof trees, which represent the local processes as much as they do the global processes. The second and third methods are related, respectively to Soundness criteria verification, Relaxed Soundness and Weak Soundness for the interorganizational workflow processes. These are obtained through the analysis of reutilized Linear Logic proof trees that have been constructed for the verification of the Soundness criteria. However, the fourth method has the objective of detecting the deadlock free scenarios in interorganizational workflow and is based on the construction and analysis of Linear Logic proof trees, which initially takes into consideration the local processes and communication between such, and thereafter the candidate scenarios. A case study is carried out in the context of a Web services composition check, since there is a close correlation between the modelling of the interorganizational workflow process and a Web services composition. Therefore, the four methods proposed in the interorganizational workflow process context, are applied to a Web services composition. The evaluation of the obtained results shows that the reutilization of Linear Logic proof trees initially constructed for verifying the Soundness criteria, in fact occurs in the context of verifying the Relaxed Soundness andWeak Soundness criteria. In addition, the evaluation shows how the Linear Logic sequents and their proof trees explicitly show the possibilities for existing collaborations in a Web service composition. An evaluation that takes into account the number of constructed linear logic proof trees shows that this number can be significantly reduced in the deadlock-freeness scenarios detection method. An approach for resource planning based on the symbolic date calculation, which considers data extracted from Linear Logic proof trees is presented and validated through simulations performed on the CPN tools simulator. Two approaches for the monitoring of deadlockfreeness scenarios are introduced and show how data obtained from the Linear Logic proof trees can be used to guide the execution of such scenarios. / Este trabalho formaliza quatro métodos baseados na Lógica Linear para verificação de processos de workflow interorganizacionais modelados por WorkFlow nets interorganizacionais, que são redes de Petri que modelam tais processos. O primeiro método está relacionado com a verificação do critério de correção Soundness para processos de workflow interorganizacionais. O método é baseado na construção e análise de árvores de prova da Lógica Linear que representam tanto os processos locais quanto o processo global. O segundo e terceiro métodos estão relacionados, respectivamente, com a verificação dos critérios de correção Relaxed Soundness e Weak Soundness para processos de workflow interorganizacionais, e são obtidos através da análise de árvores de prova da Lógica Linear reutilizadas, construídas para a prova do critério de correção Soundness. Já o quarto método tem por objetivo a detecção dos cenários livres de deadlock em processos de workflow interorganizacionais e é baseado na construção e análise de árvores de prova da Lógica Linear que consideram, inicialmente, os processos locais e as comunicações entre estes e, posteriormente, os cenários candidatos. Um estudo de caso é realizado no contexto da verificação de composições de serviços Web, uma vez que há uma relação estreita entre a modelagem de um processo de workflow interorganizacional e uma composição de serviços Web. Assim, os quatro métodos propostos no contexto dos processos de workflow interorganizacionais são aplicados a uma composição de serviços Web. A avaliação dos resultados mostra que o reuso de árvores de prova da Lógica Linear construídas inicialmente para a prova do critério de correção Soundness de fato ocorre no contexto da verificação dos critérios de correção Relaxed Soundness e Weak Soundness. Além disso, a avaliação mostra como os sequentes da Lógica Linear e suas árvores de prova explicitam as possibilidades de colaboração existentes em uma composição de serviços Web. Uma avaliação que leva em conta o número de árvores de prova da Lógica Linear construídas mostra que este número pode ser significativamente reduzido no método para detecção de cenários livres de deadlock. Uma abordagem para planejamento de recursos, baseada no cálculo de datas simbólicas, que considera dados extraídos de árvores de prova da Lógica Linear, é apresentada e validada através de simulações realizadas no simulador CPN Tools. Duas abordagens para a monitoração dos cenários livres de deadlock são introduzidas e mostram como dados obtidos nas árvores de prova da Lógica Linear podem ser utilizados para guiar a execução de tais cenários. / Doutor em Ciência da Computação
13

Konkurence, efektivita a zdraví v bankovnictví / Competition, efficiency and soundness in banking

Jankovská, Alžběta January 2014 (has links)
There is an ongoing debate whether the impact of competition on bank soundness is positive or negative. Traditionally, it was assumed that there is a trade-off between competition and bank soundness. On the other hand, some recent studies suggest that competition has a positive effect on bank soundness. In this thesis, we will focus on the concept of efficiency as a possible link between competition and bank soundness. Firstly, we will summarize different approaches to measure competition, efficiency and soundness in banking sector. Subsequently, we will focus on hypotheses formulated to describe the link between competition in financial sector and bank soundness, between efficiency and bank soundness and between bank competition and efficiency. The empirical part, we will examine whether there is a link between competition and soundness via efficiency channel. Our analysis is based on dataset contains commercial banks from Visegrad group during period 2008 - 2012. We will exploit the Boone indicator as a measure of competition, the SFA approach to obtain efficiency score and soundness will be derived from z-score. The empirical evidence confirmed the positive link between competition and bank soundness via efficiency channel.
14

Computational soundness of formal reasoning about indistinguishability and non-malleability of cryptographic expressions

Hajiabadi, Mohammad 24 August 2011 (has links)
Analysis and verification of security protocols are typically carried out in two different models of cryptography: formal cryptography and computational cryptography. Formal cryptography, originally inspired by the work of Dolev and Yao [14], takes an abstract and idealized view of security, and develops its proof techniques based on methods and ideas from logic and theory of programming languages. It makes strong assumptions about cryptographic operations by treating them as perfectly-secure symbolic operations. Computational cryptography, on the other hand, has developed its foundations based on complexity theory. Messages are viewed as bit-strings, and cryptographic operations are treated as actual transformations on bit-strings with certain asymptotic properties.In this thesis, we explore the relation between the Dolev-Yao model and the computational model of public-key cryptography in two contexts: indistinguishability and non-malleability of expressions. This problem in the absence of key-cycles is partially addressed in [20, 21] by Herzog. We adapt our approach to use the co-inductive definition of symbolic security, whose private-key treatment was considered in coinduction, and establish our main results as follow: Using a co-inductive approach, we extend the indistinguishability and non-malleability results of Herzog in the presence of key-cycles. By providing a counter-example, we show that the indistinguishability property in this setting is strictly stronger than the non-malleability property, which gives a negative answer to Herzog's conjecture that they are equivalent. we prove that despite the fact that IND-CCA2 security provides non-malleability in our setting, the same result does not hold for IND-CCA1 security. We prove that, under certain hypothesis, our co-inductive formal indistinguishability is computationally-complete in the absence of key-cycles and with respect to any \emph{length-revealing} encryption scheme. In the presence of key-cycles, we prove that the completeness does not hold even with respect to IND-CPA security. / Graduate
15

Evaluation of peripubertal replacement breeding animals in beef herds

Monday, Jessica Dawn January 1900 (has links)
Master of Science in Veterinary Biomedical Science / Department of Clinical Sciences / Robert L. Larson / The selection of young replacement animals can have a significant impact on beef herd reproductive performance. Replacement heifers can be utilized to improve reproductive performance by replacing mature animals that failed to meet the production with young, cycling heifers that can have the potential of improving the reproductive momentum of a herd. The use of yearling bulls in natural breeding herds has the advantage of shortening the generational interval of the herd and has the potential of reducing the cost per cow exposed as additions to the bull battery. This thesis involves two studies that investigated methods used for the selection of peripubertal replacement animals in beef herds. The first study evaluated the ability of the novel Ready-Intermediate-Problem (RIP) replacement heifer evaluation matrix to classify heifers into groups that allow producers to select for replacements that meet production goals. Beef heifers (n=341) were classified according to the RIP matrix guidelines and then exposed to AI breeding, bull breeding, or a combination of both as per the management plans for each participating herd. Following breeding season the heifers were evaluated to determine pregnancy status, pregnancy status to single AI exposure, days bred, and the number of 21 day cycles needed during breeding season to become pregnant. After breeding season, 298 (87%) of the heifers were pregnant, 204 (68%) of which became pregnant in the first 21 days of the breeding season. Probability of overall pregnancy and pregnancy after single AI exposure was not significantly associated with RIP classification. There was a significant interaction in RIP classification by 21 day cycle. The second study was a retrospective study using BSE result data to determine the proportion of yearling beef bulls that are classified as satisfactory potential breeders when reevaluated after failing their initial breeding soundness evaluation (BSE) and to identify any predictive factors at initial BSE for satisfactory performance at revaluation. The study included 2,805 beef bulls between 11 and 14 months of age at first BSE evaluated at KABSU from 2006 to 2014. Generalized linear mixed models were created to assess potential associations among breed, age, and interaction between breed and age and passing the initial evaluation and identify predictive factors for risk of passing BSE after initial failure. The majority (93%) of the study bulls passed one of up to three BSEs. There was a significant interaction between age and breed of bull at initial BSE. Identification of suitable peripubertal replacement animals that will improve herd reproductive performance remains a challenge for producers. There are several factors that can affect replacement animals’ ability to perform according to expectations at the beginning of the breeding season. Classification of heifers into categories that can predict performance during breeding season with reasonable confidence can assist producers in identifying heifers that complement the reproductive performance goals of the herd. Utilizing BSE to identify bulls that have adequate semen quality as well as other traits important for breeding soundness is similarly important in reducing the risks of using young bulls for breeding.
16

Evaluation of soundness and seismic behavior of long-term-use irrigation dams / 長期供用農業用ダムの健全性および地震時挙動評価

Hayashida, Yoichi 26 March 2018 (has links)
京都大学 / 0048 / 新制・論文博士 / 博士(農学) / 乙第13183号 / 論農博第2862号 / 新制||農||1061(附属図書館) / 学位論文||H30||N5105(農学部図書室) / (主査)教授 村上 章, 教授 藤原 正幸, 教授 渦岡 良介 / 学位規則第4条第2項該当 / Doctor of Agricultural Science / Kyoto University / DFAM
17

Developing a new multidimensional index of bank stability and its usage in the design of optimal policy interventions

Gulati, R., Hassan, M.K., Vincent, Charles 16 May 2023 (has links)
Yes / This study proposes an optimisation-based “benefit-of-the-doubt” (BoD) methodological framework for developing a new multidimensional index of bank stability. The proposed index has the ability to serve as a potent policy tool that overcomes the downsides of accounting- and market-based measures of bank stability. This data-driven approach generates endogenous weights for aggregating bank stability indicators and dimensions. Further, we integrate the BoD framework with a metafrontier approach, which we call a “meta-BoD framework”. The final outcomes of the suggested framework go beyond a scalar measure of bank stability and provide the unique weighting matrix that offers valuable policy-relevant insights about the most precarious areas of stability that require the attention of management and regulators for both micro- and macro-level policy interventions. In addition, it draws insightful information about the instability gaps across heterogenous bank groups. The study presents an illustrative example of the proposed framework to obtain a bank stability index using the dataset of 76 Indian banks operating between 2014 and 2018. The bank stability index is made up of 14 financial ratio indicators covering five dimensions of stability: asset quality, management efficiency, capital adequacy, profitability and liquidity. The findings offer the detailed information required for comprehending the evolution of bank stability and assessing instability gaps across bank groups.
18

On Reducing the Trusted Computing Base in Binary Verification

An, Xiaoxin 15 June 2022 (has links)
The translation of binary code to higher-level models has wide applications, including decompilation, binary analysis, and binary rewriting. This calls for high reliability of the underlying trusted computing base (TCB) of the translation methodology. A key challenge is to reduce the TCB by validating its soundness. Both the definition of soundness and the validation method heavily depend on the context: what is in the TCB and how to prove it. This dissertation presents three research contributions. The first two contributions include reducing the TCB in binary verification, and the last contribution includes a binary verification process that leverages a reduced TCB. The first contribution targets the validation of OCaml-to-PVS translation -- commonly used to translate instruction-set-architecture (ISA) specifications to PVS -- where the destination language is non-executable. We present a methodology called OPEV to validate the translation between OCaml and PVS, supporting non-executable semantics. The validation includes generating large-scale tests for OCaml implementations, generating test lemmas for PVS, and generating proofs that automatically discharge these lemmas. OPEV incorporates an intermediate type system that captures a large subset of OCaml types, employing a variety of rules to generate test cases for each type. To prove the PVS lemmas, we develop automatic proof strategies and discharge the test lemmas using PVS Proof-Lite, a powerful proof scripting utility of the PVS verification system. We demonstrate our approach in two case studies that include 259 functions selected from the Sail and Lem libraries. For each function, we generate thousands of test lemmas, all of which are automatically discharged. The dissertation's second contribution targets the soundness validation of a disassembly process where the source language does not have well-defined semantics. Disassembly is a crucial step in binary security, reverse engineering, and binary verification. Various studies in these fields use disassembly tools and hypothesize that the reconstructed disassembly is correct. However, disassembly is an undecidable problem. State-of-the-art disassemblers suffer from issues ranging from incorrectly recovered instructions to incorrectly assessing which addresses belong to instructions and which to data. We present DSV, a systematic and automated approach to validate whether the output of a disassembler is sound with respect to the input binary. No source code, debugging information, or annotations are required. DSV defines soundness using a transition relation defined over concrete machine states: a binary is sound if, for all addresses in the binary that can be reached from the binary's entry point, the bytes of the (disassembled) instruction located at an address are the same as the actual bytes read from the binary. Since computing this transition relation is undecidable, DSV uses over-approximation by preventing false positives (i.e., the existence of an incorrectly disassembled reachable instruction but deemed unreachable) and allowing, but minimizing, false negatives. We apply DSV to 102 binaries of GNU Coreutils with eight different state-of-the-art disassemblers from academia and industry. DSV is able to find soundness issues in the output of all disassemblers. The dissertation's third contribution is WinCheck: a concolic model checker that detects memory-related properties of closed-source binaries. Bugs related to memory accesses are still a major issue for security vulnerabilities. Even a single buffer overflow or use-after-free in a large program may be the cause of a software crash, a data leak, or a hijacking of the control flow. Typical static formal verification tools aim to detect these issues at the source code level. WinCheck is a model-checker that is directly applicable to closed-source and stripped Windows executables. A key characteristic of WinCheck is that it performs its execution as symbolically as possible while leaving any information related to pointers concrete. This produces a model checker tailored to pointer-related properties, such as buffer overflows, use-after-free, null-pointer dereferences, and reading from uninitialized memory. The technique thus provides a novel trade-off between ease of use, accuracy, applicability, and scalability. We apply WinCheck to ten closed-source binaries available in a Windows 10 distribution, as well as the Windows version of the entire Coreutils library. We conclude that the approach taken is precise -- provides only a few false negatives -- but may not explore the entire state space due to unresolved indirect jumps. / Doctor of Philosophy / Binary verification is a process that verifies a class of properties, usually security-related properties, on binary files, and does not need access to source code. Since a binary file is composed of byte sequences and is not human-readable, in the binary verification process, a number of assumptions are usually made. The assumptions often involve the error-free nature of a set of subsystems used in the verification process and constitute the verification process's trusted computing base (or TCB). The reliability of the verification process therefore depends on how reliable the TCB is. The dissertation presents three research contributions in this regard. The first two contributions include reducing the TCB in binary verification, and the last contribution includes a binary verification process that leverages a reduced TCB. The dissertation's first contribution presents a validation on OCaml-to-PVS translations -- commonly used to translate a computer architecture's instruction specifications to PVS, a language that allows mathematical specifications. To build up a reliable semantical model of assembly instructions, which is assumed to be in the TCB, it is necessary to validate the translation. The dissertation's second contribution validates the soundness of the disassembly process, which translates a binary file to corresponding assembly instructions. Since the disassembly process is generally assumed to be trustworthy in many binary verification works, the TCB of binary verification could be reduced by validating the soundness of the disassembly process. With the reduced TCB, the dissertation introduces WinCheck, the dissertation's third and final contribution: a concolic model checker that validates pointer-related properties of closed-source Windows binaries. The pointer-related properties include absence of buffer overflow, absence of use-after-free, and absence of null-pointer dereference.
19

Circumscriptive reasoning

Halland, Kenneth John 08 1900 (has links)
We show how the non-monotonic nature of common-sense reasoning can be formalised by circumscription. Various forms of circumscription are discussed. A new form of circumscription, namely naive circumscription, is introduced in order to facilitate the comparison of the various forms. Finally, some issues connected with the automation of circumscriptive reasoning are examined. / Computing / M. Sc. (Computer Science)
20

Estudo genético quantitativo das características andrológicas de touros jovens da raça Nelore /

Silva, Márcio Ribeiro. January 2009 (has links)
Resumo: Diante do grande impacto da fertilidade dos touros sobre as eficiências reprodutiva e produtiva em rebanhos comerciais, o presente trabalho foi realizado visando avaliar as características testiculares e seminais como critérios de seleção de touros jovens da raça Nelore. As correlações fenotípicas foram, de modo geral, baixas ou nulas (P<0,01) entre as características testiculares, seminais e de crescimento. Todas as características testiculares ou seminais deverão ser contempladas no exame andrológico, visto a independência existente entre as mesmas e a importância destas na comprovação da fertilidade de touros. Os componentes de (co)variância e os valores genéticos foram estimados pelo método da amostragem de Gibbs pelo programa GIBBS2F90, sob modelo animal, o qual incluiu como efeitos fixos, os grupos de contemporâneos e a idade do animal e como aleatório o efeito genético aditivo direto. As estimativas de herdabilidade para perímetro escrotal aos 18 meses, perímetro escrotal no andrológico, volume testicular, formato testicular, aptidão andrológica, defeitos espermáticos maiores, menores e totais foram: 0,42; 0,41; 0,23; 0,22; 0,10; 0,16; 0,04 e 0,15. As correlações genéticas entre perímetro escrotal aos 18 meses com as demais características testiculares e aptidão andrológica foram baixas a altas, de 0,20 a 0,84 e, baixas com as seminais, de -0,16 a -0,24. A circunferência escrotal como critério de seleção deverá promover ganho genético rápido por seleção individual e, por resposta correlacionada, aumento do volume testicular, mudança para formas mais esféricas dos testículos, melhoria da qualidade seminal e aumento do número de animais aptos à reprodução nas condições extensivas de criação no Brasil. / Abstract: Considering the great impact of fertility of bulls on reproductive and productive efficiency in commercial herds, the objective of this study was to evaluate the testicular and seminal traits as selection criteria of Nellore young bulls. The residual correlations between the traits were analyzed and, in general, the phenotypic associations were small (P<0.01) or null between the testicular, seminal and growth traits. The testicular or seminal traits should be considered in breeding soundness examination, due to their independence of each other and the importance to fertility of bulls. The genetic (co)variance components and genetic values were estimated by the Gibbs sampling method, using the program GIBBS2F90, under an animal model, which included, as fixed effects, the contemporary groups and animal age and, as random effect, the additive genetic effect. The heritability estimates for scrotal circumference at 18 months, scrotal circumference, testicular volume, testicular format, breeding soundness classification, major sperm defects, minor and total sperm defects were: 0.42, 0.41, 0.23, 0.22, 0.10., 0.16, 0.04 and 0.15. Genetic correlations between scrotal circumference at 18 months and others testicular traits and breeding soundness classification were low to high (0.20 to 0.84) and, with seminal traits was low (-0.16 to - 0.24). The scrotal circumference as a selection criterion should result in rapid genetic gain by individual selection, and as correlated response, should result in testicular volume, changes to more spherical shapes of the testicles, improved sperm quality and increased number of satisfactory bulls for breeding under extensive conditions in Brazil. / Orientadora: Lúcia Galvão de Albuquerque / Coorientador: Joanir Pereira Eler / Banca: José Bento Sterman Ferraz / Banca: José Domingos Guimarães / Banca: Humberto Tonhati / Banca: Maurício Mello de Alencar / Doutor

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