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1
Katamine, Eiji, Hideyuki Azegami, and Akiyoshi Okitsu. "Shape Optimization Analysis of Flow Field : Growth-Strain Method Approach." 日本機械学会, 1994. http://hdl.handle.net/2237/12157.
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Rajagopalan, Ramachandran. "Bifurcation analysis of the structure of vortices in an uniform strain field." Diss., The University of Arizona, 1989. http://hdl.handle.net/10150/184732.
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We have studied the stationary solutions to the two-dimensional Euler's equation. A highly accurate scheme, based on boundary integral techniques was used in investigating these steady-state configurations. Bifurcation analysis on the solution of a uniform vortex patch in an externally applied strain field, yield new non-elliptical steady-state solutions apart from the elliptical structures reported by Moore & Saffman. The elliptical solutions correspond to the points on the primary solution branch and the non-elliptical solutions correspond to points on the bifurcation branches. We also observe the presence of a turning point indicating the finite resistance of these uniform vortices. Some of these new solutions suggest the possibility of coalescence between neighboring vortices. This leads to a new problem of considering a vortex pair in a strain field and computing their steady-state solutions. Numerical computations suggest that this guess is indeed correct, as we see the solution branch corresponding to the vortex pair intersect the bifurcation branch of the single vortex at a unique strain rate. Furthermore, looking at the profiles on the other bifurcation branches, it appears that merger of neighboring vortices is a recurring phenomenon.
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Bethke, Kristen (Kristen Ann). "The second skin approach : skin strain field analysis and mechanical counter pressure prototyping for advanced spacesuit design." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/32443.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2005.Includes bibliographical references.
The primary aim of this thesis is to advance the theory of advanced locomotion mechanical counter pressure (MCP) spacesuits by studying the changes in the human body shape during joint motion. Two experiments take advantage of three-dimensional laser scan technology to measure the shape changes of the human body. The first experiment is an analysis of the surface area and volume of the thigh, knee, calf, and entire leg during knee flexion. The second experiment is an analysis of the full-field strain on the skin surface of the leg during knee flexion. A repeatable and quantitative technique for mapping the leg skin strain field is developed. The results of the algorithm indicate the magnitude of strain over the entire surface of the leg, as well as the direction of minimum leg skin stretching during knee flexion. For 88% of the leg surface, knee flexion causes skin strain between -0.3 and 0.3 (less than 30% contraction or extension). However, just below the patella, longitudinal strain is as high as 0.7, and at the knee hollow, it is as low as -0.6. Circumferential strain values are as high as 1.0 and 0.5 just below the patella and over the calf muscle, respectively, and along the anterior surface of the lower leg, they are as low as -0.7. The leg area, volume, and skin strain results lead to quantitative design requirements for highly mobile second skin spacesuits, and they inspire two prototype MCP leg sleeves: a hybrid urethane-foam bladder garment and a skintight nylon fiber lines of non-extension garment. These two prototypes are constructed and tested for mobility and skin surface pressure. Pressurization of the hybrid foam prototype inhibits leg mobility.
(cont.) However, the nylon lines of non-extension prototype shows promise as an advanced locomotion spacesuit design concept. During pressurization to leg surface pressure of 7.5 kPa (56 mmHg, 1.1 psi), the prototype preserves easy mobility to 90 degrees of knee joint flexion. Recommendations are made for improving its pressure production performance to the desired 30 kPa (222 mmHg, 4.3 psi) level.
by Kristen Bethke.
S.M.
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Kellermann, David Conrad Mechanical & Manufacturing Engineering Faculty of Engineering UNSW. "Strongly orthotropic continuum mechanics." Publisher:University of New South Wales. Mechanical & Manufacturing Engineering, 2008. http://handle.unsw.edu.au/1959.4/41454.
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The principal contribution of this dissertation is a theory of Strongly Orthotropic Continuum Mechanics that is derived entirely from an assertion of geometric strain indeterminacy. Implementable into the finite element method, it can resolve widespread kinematic misrepresentations and offer unique and purportedly exact strain-induced energies by removing the assumptions of strain tensor symmetry. This continuum theory births the proposal of a new class of physical tensors described as the Intrinsic Field Tensors capable of generalising the response of most classical mechanical metrics, a number of specialised formulations and the solutions shown to be kinematically intermediate. A series of numerical examples demonstrate Euclidean objectivity, material frame-indifference, patch test satisfaction, and agreement between the subsequent Material Principal Co-rotation and P??I??C decomposition methods that produce the intermediary stress/strain fields. The encompassing theory has wide applicability owing to its fundamental divergence from conventional mechanics, it offers non-trivial outcomes when applied to even very simple problems and its use of not the Eulerian, Lagrangian but the Intrinsic Frame generates previously unreported results in strongly orthotropic continua.
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Villanueva, Jorge Luis Chacón. "Epidemiologia molecular do vírus da laringotraqueíte infecciosa isolados de surtos em poedeiras comerciais no Estado de São Paulo." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/10/10133/tde-23012009-155035/.
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Este estudo teve como objetivo detectar e caracterizar molecularmente isolados de campo do vírus da laringotraqueíte infecciosa (VLTI) detectados de aves comerciais com e sem sintomatologia da doença de diferentes regiões do Estado de São Paulo. O estudo incluiu amostras coletadas durante e após o primeiro surto epidêmico da laringotraqueíte infecciosa (LTI) no Brasil, região de Bastos, e de outras localidades durante o período de 2002-2008. A caracterização molecular foi realizada através da técnica de polimorfismo do comprimento de fragmentos de restrição (RFLP) de produtos da reação em cadeia pela polimerase (PCR) dos genes da glicoproteína E, G, proteína quinase (TK) e da proteína reguladora da transcrição (ICP4), assim como pela análise de seqüências dos genes TK e ICP4. Para seqüenciamento do gene ICP4 foram desenvolvidas duas reações de PCR que amplificam dois diferentes fragmentos do gene ICP4. As técnicas de PCR-RFLP e seqüenciamento de DNA mostraram resultados idênticos, diferenciando os isolados de campo das cepas vacinais de origem de cultivo celular (TCO) e de embrião de galinha (CEO). Os resultados mostraram que o surto clínico na região de Bastos foi causado por uma cepa não vacinal e de alta virulência (cepa Bastos), embora também tenha sido possível detectar dois isolados relacionados à cepa CEO circulando durante o surto. Verificou-se que a cepa causadora do surto severo na região de Bastos continua circulando na região apesar do uso de vacinas atenuadas. Além disso, foram isoladas amostras relacionadas às cepas CEO e à cepa Bastos apartir de granjas comerciais de poedeiras localizadas fora da região de Bastos e que estão envolvidas em quadros clínicos da doença. Este estudo mostra (1): a persistência do vírus selvagem de campo na região de Bastos (cepa Bastos) apesar das medidas de controle e do uso de vacinas atenuadas, (2): a disseminação da cepa Bastos e das cepas vacinais CEO para outras regiões, e (3): a eficacia da estratégia padronizada neste estudo para a caracterização e diferenciação de isolados de campo e de cepas vacinais.The objective of this study was the molecular detection and characterization of field isolates of infectious laryngotracheitis virus (ILTV) detected from commercial chickens with and without clinical signs of the disease from regions of the São Paulo state. The study included samples collected during and after of the first epidemic infectious laryngotracheitis (ILT) outbreak in Brazil, Bastos region, and from other regions during 2002-2008. The molecular characterization was developed by restriction fragment length polymorphic analysis (RFLP) of polymerase chain reaction (PCR) products of glycoprotein E, G, thymidine kinase (TK) and regulatory protein of transcription (ICP4) gene, and by sequence analysis of TK and ICP4 gene. For ICP4 gene sequencing, two PCR assays have been developed for amplification of two different fragments of ICP4 gene. The PCR-RFLP and DNA sequencing techniques showed identical results, they could differentiate the field isolates from vaccine strains, tissue culture origin (TCO) and chicken embryo origin (CEO). The results showed that the severe outbreak in Bastos region was caused by a non-vaccine and virulent strain (Bastos strain); however it was possible to detect two isolates closely related to the CEO vaccine strain circulating during the outbreak. This study showed that the strain, which it caused the severe outbreak in Bastos region continue circulating in these region despite of the use of attenuate vaccines. In addition, the present research showed that isolates related to CEO and Bastos strains are circulating in commercial layer flocks located outside the Bastos region, and were involving in clinical cases of the disease. This study shows (1) the persistence of the wild field strain in Bastos region (Bastos strain) despite of the control measures and the use of attenuate vaccines, (2) the dissemination of the Bastos and CEO strains to other regions, and (3) the efficacy of the strategy standardized in this study to characterization and differentiation of field isolates and vaccine strain.
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Knarr, Brian A. "Design and analysis of a finite element model of the biceps brachii integrated with dynamic in vivo strain fields." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 196 p, 2008. http://proquest.umi.com/pqdweb?did=1650507211&sid=4&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Box, Matthew. "Multiple-locus variable-number tandem-repeat analysis (MLVA) for clonal characterization of methicillin resistant Staphylococcus aureus strains." Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2006. https://www.mhsl.uab.edu/dt/2008r/box.pdf.
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Jere, Khuzwayo Chidiwa. "Whole genome characterisation and engineering of chimaeric rotavirus-like particles using African rotavirus field strains / Khuzwayo Chidiwa Jere." Thesis, North-West University, 2012. http://hdl.handle.net/10394/8502.
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Despite the global licensure of two live-attenuated rotavirus vaccines, Rotarix® and
RotaTeq®, rotavirus remains the major cause of severe dehydrating diarrhoea in young
mammals and the need for further development of additional rotavirus vaccines, especially
vaccines effective against regional strains in developing country settings, is increasing. The
design and formulation of new effective multivalent rotavirus vaccines is complicated by the
wide rotavirus strain diversity. Novel rotavirus strains emerge periodically due to the
propensity of rotaviruses to evolve using mechanisms such as point mutation, genome
segment reassortment, genome segment recombination and interspecies transmission.
Mutations occurring within the primer binding regions targeted by the current commonly
employed sequence-dependent genotyping techniques lead to difficulties in genotyping novel
mutant rotavirus strains. Therefore, use of sequence-independent techniques coupled with
online rotavirus genotyping tools will help to understand the complete epidemiology of the
circulating strains which, in turn, is vital for developing intervention measures such as
vaccine and anti-viral therapies.
In this study, sequence-independent cDNA synthesis that uses a single set of oligonucleotides
that do not require prior sequence knowledge of the rotavirus strains, 454® pyrosequencing,
and an online rotavirus genotyping tool, RotaC, were used to swiftly characterise the whole
genome of rotaviruses. The robustness of this approach was demonstrated in characterising
the complete genetic constellations and evolutionary origin of selected human rotavirus
strains that emerged in the past two decades worldwide, human rotavirus strains frequently
detected in Africa, and the whole genomes of some common strains frequently detected in
bovine species. Most of the characterised strains emerged either through intra- or interspecies
genome segment reassortment processes. The methods used in this study also allowed
determination of the whole consensus genome sequence of multiple rotavirus variants present
in a single stool sample and the elucidation of the evolutionary mechanisms that explained
their origin. The 454® pyrosequence-generated data revealed evidence of intergenotype
rotavirus genome segment recombination between the genome segments 6 (VP6), 8 (NSP2)
and 10 (NSP4) of Wa-like and DS-1-like origin. The use of next generation sequencing technology combined with sequence-independent
amplification of the rotavirus genomes allowed the determination of the consensus nucleotide
sequence for each of the genome segments of the selected study strains directly from stool
sample.
The consensus nucleotide sequences of the genome segments encoding VP2, VP4, VP6 and
VP7 of some of the study strains were codon optimised for insect cell expression and used to
generate recombinant baculoviruses. The Bac-to-Bac baculovirus expression system was used
to generate chimaeric rotavirus virus-like particles (RV-VLPs). These chimaeric RV-VLPs
contained inner capsids (VP2 and VP6) derived from a South African RVA/Humanwt/
ZAF/GR10924/1999/G9P[6] strain, on to which outer capsid layer proteins composed of
various combinations of VP4 and VP7 were assembled. The outer capsid proteins were
derived from the dsRNA of G2, G8, G9 or G12 strains associated with either P[4], P[6] or
P[8] genotypes that were directly extracted from human stool faecal specimens. The
structures of these chimaeric RV-VLPs were morphologically evaluated using transmission
electron microscopy (TEM). Based on the size and morphology of the particles, doublelayered
(dRV-VLPs) and triple-layered RV-VLPs (tRV-VLPs) were produced. Recombinant
rotavirus proteins readily assembled into dRV-VLPs, whereas approximately 10 – 30% of the
assembled RV-VLPs from insect expressed recombinant VP2/6/7/4 were chimaeric tRVVLPs.
These RV-VLPs will be evaluated in future animal studies as potential non-live
rotavirus vaccine candidates. The novel approach of producing RV-VLPs introduced in this
study, namely by using the consensus nucleotide sequence derived from dsRNA extracted
directly from clinical specimens, should speed up vaccine research and development by
bypassing the need to adapt the viruses to tissue culture and circumventing some other
problems associated with cell culture adaptation as well. Thus, it is now possible to generate
RV-VLPs for evaluation as non-live vaccine candidates for any human or animal field
rotavirus strain.Thesis (PhD (Biochemistry))--North-West University, Potchefstroom Campus, 2012
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Zhu, Yan. "Mixed As/Sb and tensile strained Ge/InGaAs heterostructures for low-power tunnel field effect transistors." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/47791.
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Reducing supply voltage is a promising way to address the power dissipation in nano-electronic circuits. However, the fundamental lower limit of subthreshold slope (SS) within metal-oxide-semiconductor field-effect transistors (MOSFETs) is a major obstacle to further scaling the operation voltage without degrading ON/OFF-ratio in today's integrated circuits. Tunnel field-effect transistors (TFETs) benefit from steep switching characteristics due to the quantum-mechanical tunneling injection of carriers from source to channel, rather than by conventional thermionic emission in MOSFETs. TFETs based on group III-V compound semiconductor and Ge heterostructures further improve the ON-state current and reduce SS due to the low bandgap energies and smaller carrier tunneling mass. The mixed arsenide/antimonide (As/Sb) InxGa1-xAs/GaAsySb1-y and Ge/InxGa1-xAs heterostructures allow a wide range of bandgap energies and various band alignments depending on the alloy compositions in the source and channel materials. Band alignments at source/channel heterointerface can be well modulated by carefully controlling the compositions of the InxGa1-xAs or GaAsySb1-y. In particular, this research systematically investigate the development and optimization of low-power TFETs using mixed As/Sb and Ge/InxGa1-xAs based heterostructures including: basic working principles, design considerations, material growth, interface engineering, material characterization, band alignment determination, device fabrication, device performance investigation, and high-temperature reliability. A comprehensive study of TFETs using mixed As/Sb and Ge/InxGa1-xAs based heterostructures shows superior structural properties and distinguished device performances, both of which indicate the mixed As/Sb and Ge/InxGa1-xAs based TFET as a promising option for high performance, low standby power and energy efficient logic circuit application.Ph. D.
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Staudinger, Ulrike. "Morphologie und Bruchverhalten von Block- und Multipfropfcopolymeren." Doctoral thesis, [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:swb:14-1187261828675-34703.
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Buck, Dietrich. "Mechanics of Cross-Laminated Timber." Licentiate thesis, Luleå tekniska universitet, Träteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-68729.
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Increasing awareness of sustainable building materials has led to interest in enhancing the structural performance of engineered wood products. Wood is a sustainable, renewable material, and the increasing use of wood in construction contributes to its sustainability. Multi-layer wooden panels are one type of engineered wood product used in construction. There are various techniques to assemble multi-layer wooden panels into prefabricated, load-bearing construction elements. Assembly techniques considered in the earliest stages of this research work were laminating, nailing, stapling, screwing, stress laminating, doweling, dovetailing, and wood welding. Cross-laminated timber (CLT) was found to offer some advantages over these other techniques. It is cost-effective, not patented, offers freedom of choice regarding the visibility of surfaces, provides the possibility of using different timber quality in the same panel at different points of its thickness, and is the most well-established assembly technique currently used in the industrial market. Building upon that foundational work, the operational capabilities of CLT were further evaluated by creating panels with different layer orientations. The mechanical properties of CLT panels constructed with layers angled in an alternative configuration produced on a modified industrial CLT production line were evaluated. Timber lamellae were adhesively bonded in a single-step press procedure to form CLT panels. Transverse layers were laid at a 45° angle instead of the conventional 90° angle with respect to the longitudinal layers’ 0° angle. Tests were carried out on 40 five-layered CLT panels, each with either a ±45° or a 90° configuration. Half of these panels were evaluated under bending: out-of-plane loading was applied in the principal orientation of the panels via four-point bending. The other twenty were evaluated under compression: an in-plane uniaxial compressive loading was applied in the principal orientation of the panels. Quasi-static loading conditions were used for both in- and out-of-plane testing to determine the extent to which the load-bearing capacity of such panels could be enhanced under the current load case. Modified CLT showed higher stiffness, strength, and fifth-percentile characteristics, values that indicate the load-bearing capacity of these panels as a construction material. Failure modes under in- and out-of-plane loading for each panel type were also assessed. Data from out-of-plane loading were further analysed. A non-contact full-field measurement and analysis technique based on digital image correlation (DIC) was utilised for analysis at global and local scales. DIC evaluation of 100 CLT layers showed that a considerable part of the stiffness of conventional CLT is reduced by the shear resistance of its transverse layers. The presence of heterogeneous features, such as knots, has the desirable effect of reducing the propagation of shear fraction along the layers. These results call into question the current grading criteria in the CLT standard. It is suggested that the lower timber grading limit be adjusted for increased value-yield. The overall experimental results suggest the use of CLT panels with a ±45°-layered configuration for construction. They also motivate the use of alternatively angled layered panels for more construction design freedom, especially in areas that demand shear resistance. In addition, the design possibility that such 45°-configured CLT can carry a given load while using less material than conventional CLT suggests the potential to use such panels in a wider range of structural applications. The results of test production revealed that 45°-configured CLT can be industrially produced without using more material than is required for construction of conventional 90°-configured panels. Based on these results, CLT should be further explored as a suitable product for use in more wooden-panel construction.External cooperation: Martinson Group AB and Research Institutes of Sweden (RISE)
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Dia, Mouhamadou. "Hexahedral and prismatic solid-shell for nonlinear analysis of thin and medium-thick structures." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI040.
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Les structures à faibles ou moyennes épaisseurs sont naturellement présentes dans la plupart des installations de production d'énergie : bâtiment réacteur, tuyauteries sous pression, réservoirs métalliques ou bâches, cuve de réacteur, liners métalliques des enceintes de confinement pour ne citer que ceux‐là. Un besoin actuellement exprimé par les unités d'ingénierie d’EDF est la modélisation des phénomènes de cloquage de liners métalliques des bâtiments réacteur. Un liner est une structures de type tôle métallique assurant la fonction d’étanchéité des centrales nucléaires. Sa modélisation nécessite la prise en compte d’un phénomène de contact-frottement engendrant du pincement sur la coque, de la plasticité sous l’effet de cloquage et de la non linéarité géométrique (instabilité de type flambement). Pour modéliser le comportement thermomécanique d’une structure pareille, les éléments finis de plaques et coques actuellement disponible ne semblent pas être à la hauteur. Le premier verrou attribuable à ces éléments est l’hypothèse des contraintes planes qui empêche la prise en compte de certaines lois de comportement nativement tridimensionnelles. En deuxième lieu, du fait de leur formulation avec des degrés de liberté de rotations ces éléments n’offrent pas une facilité d’utilisation lorsqu’il s’agit de résoudre des problèmes prenant en compte les effets non-linéaires telles que les grande transformations géométriques, le contact-frottement bi-facial, le flambement et les pressions suiveuses. Une alternative serait d’utiliser des éléments volumiques standards. Cependant le coût de calcul prohibitif des ces derniers est difficilement accessible pour de nombreuses applications industrielles. Le but de ces travaux est de proposer une solution à cette problématique. Nous avons proposé une formulation élément fini de type solide-coque enrichie en pincement et capable de reproduire les comportements des structures minces avec une précision satisfaisante. Ce nouvel éléments fini fonctionnent avec tout type de loi de comportement tridimensionnelle sans restriction sur les champs de contraintes. On peut également l’utiliser pour tous les types de problèmes mécaniques : linéaire et non linéaire, contact frottement, grande transformation, flambement, pression suiveuse etc. Les simulations numériques réalisées montrent des performances satisfaisantesThin or medium-thick structures are naturally present in most power generation facilities: reactor building, pressurized pipelines, metal tanks or tarpaulins, reactor vessel, metal liners of containment chambers, to name but a few. A need currently expressed by EDF's engineering units is the modeling of the blistering phenomena of metal liners in reactor facilities. A liner is a metal sheet type structure that provides the impermeability function of nuclear power plants. Its modeling requires taking into account a contact-friction phenomenon causing pinching on the shell, plasticity under the effect of blistering and geometric nonlinearity (buckling type instability). To model the thermo-mechanical behavior of such a structure, the finite elements of plates and shells currently available do not seem to be up to the task. The first limitation attributable to these elements is the assumption of plane stresses which prevents the consideration of some natively three-dimensional constitutive laws. Secondly, due to their formulation with rotational degrees of freedom these elements do not offer facility of use when solving problems that take into account non-linear effects such as large geometric transformations, bi-facial friction-contact, buckling and following pressures. An alternative would be to use standard volume elements. However, the prohibitive computing cost of the latter is difficult to access for many industrial applications. The aim of this work is to propose a solution to this problem. We have proposed a solid-shell finite element formulation enriched in their pinching stress and strain and capable of reproducing accurately the behaviour of thin structures. This new finite element works with any type of three-dimensional behaviour law without restriction on stress fields. It can also be used for all types of mechanical problems: linear and nonlinear, frictional contact, large transformation, buckling, displacement-dependent pressure, etc. The numerical simulations carried out show satisfactory performances
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Antoine, Pierre-Cornélius. "Etude des dalles sur sols renforcés au moyen d'inclusions rigides ou non." Doctoral thesis, Universite Libre de Bruxelles, 2010. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209997.
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Soft soil reinforcement by inclusion is a growing technique caracterized by a pile grid and a granular embankment introduced between the reinforced soil and the structure. Unlike traditionnal methods, the load is partially transferred to the pile heads by arching in the embankment. The application area of this research focuses on the shallow foundations case, in which the thickness of the embankment is small. The litterature review shows that only a few studies were dedicated to that case, and that fundamental questions remains concerning the load transfer in the embankment. Chosen method for this research consists in two-dimensionnal physical modelling, analysis of the conducted simulations, and development of an analytical model in order to predict the load transfer to the piles by arching in the embankment. The results of this PhD thesis provide original elements of evidence of the load transfer in the studied system, proposes an analytical model based on block division of the granular embankment by shear bands - which is in good agreement with experimental data - and lead to a better understanding of arching in soils.Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished
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Chen, Chien-Ming, and 陳建銘. "The structural analysis method use the assumed strain field." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/28utb8.
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碩士國立臺灣科技大學
營建工程系
106
This paper attempts to solve the structural analysis with assumed strain field. This method is different from the traditional assumption of displacement field or the smooth finite element method. It is a brand new attempt. This method performs well when solving one-dimensional member. There are two advantages of this method, first the strain field can use a relatively simple function like the linear function, second the error of displacement can be reduced by integration. However, it can not get results of satisfaction when trying a two-dimensional plane problem so far.
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Atzori, Laura. "Sevways field lab on internationalisation - the financial strain of an international expansion." Master's thesis, 2021. http://hdl.handle.net/10362/123220.
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This thesis provides the financial analysis of the suggested internationalization strategy for Sevways. A reformulation of the company financial statement is conducted to get an indication of how the shipping business performed until the international expansion. Following upon this, a forecast of the revenues and costs during the six-year period is conducted. Discounted cash flows, sensitivity, and break-even outcomes are analysed to determine the profitability and potential of the overall project. Finally, upside and downside scenarios are presented to evaluate the project feasibility under different circumstances. The conclusion provides a positive outcome for the suggested strategy.
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Lo, Yun-Hwa, and 羅雲華. "A slip line field analysis for plane strain extrusion through curved die." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/23851285547706337503.
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Huang, Shu-yi, and 黃書誼. "Measurement of Structural Displacement and Local Strain Field Using Digital Image Analysis Processing." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/neja62.
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碩士國立中央大學
土木工程研究所
97
Displacement measurement is an important item of the health monitoring and performance evaluation of civil infrastructures. After a catastrophic earthquake or flood, large number of the population will be dislocated. The recovery processes are usually hampered by the numerous damaged civil infrastructures, some are totally and others are partially. Therefore, it is critical to determine the safety of the partially damaged infrastructures so that the society could regain their use and could help a speedy return to normalcy. Thus, there is an urgent need for reliable, robust and effective non-destructive evaluation techniques. In this thesis, digital image analysis processing is applied to position coordinates of the specific targets on a structure and to calculate displacement field. In addition, Vector Form Intrinsic Finite Element (VFIFE) Method which can remove the rigid body motion components in deformation analysis is applied to calculate the strain field of local region of a structure according to the displacement data measured by image analysis procedure. These two methods are combined to develop a non-contact and remote measurement method of strain field. Experiments of a simply-supported beam and a cantilever beam were conducted to verify and validate the proposed measurement and analysis techniques.
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Chang, An-Chi, and 張安吉. "The Sequence Analysis and Comparison of Pathogenicity in Chicken Embryo between The Fowlpox Viruses of Field Strain and Vaccine Strain." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/90075272998466026281.
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碩士國立嘉義大學
獸醫學系研究所
99
Turkeys infected with fowlpox virus (fowlpox virus; FPV) showed in two forms, one cutaneous form, another for diphtheria. There is currently no specific vaccine to prevent turkeypox virus in Taiwan. The main method used to protect turkeys against the virus were inoculation with pigeonpox vaccines of virus and chickenpox virus, although fowlpox virus infections in turkeys sporadically occurred under this method. The initially confirmed by PCR in the field fowlpox virus and vaccine strains are not the same, also found reticuloendotheliosis virus (REV) fragments inserted. Testing in fowlpox virus-positive turkey flocks was conducted to study fowlpox virus replication and identification, and to compare the results of the insertion of the reticuloendotheliosis virus between field virus isolates and vaccine strain for consideration of the relation between reticuloendotheliosis virus or virus fragment and fowlpox virus. From the period July, 2007 to June, 2009, nine fowlpox virus isolates were collected from five flocks. The infection of fowlpox virus were confirmed by clinical skin lesions, electrical technology and PCR. The methods of 4b core multi-nucleotide sequencing were used to compare with five kinds of vaccine strain in fowlpox virus-positive flocks. The histopathology observation following boosted by field strains and vaccine strains, the lesions consisted of epithelium hyperplasia, ballooning degeneration, vesicule, hemorrhage and eosinophilic intracytoplasmic inclusion bodies. Base on pathologic scores, vaccine strain more serious than field strains when detected in the 5th and 7th days post inoculation (P<0.05). Another, Comparisons of the gene sequences between nine field strains and FPV(DQ873808) were 85.5~95.0 % and Turkey(DQ873810) were 84.3 ~ 93.2 % in similarity with the identical gene. Nine field strains were identified that 5’ LTR gene of reticuloendotheliosis virus were inserted in all (9/9; 100 %). The env gene inserted in one field strain (1/9; 11 %). Both 5’ LTR gene and env gene were not inserted in three vaccine strain. The results revealed that there was a high percentage of reticuloendotheliosis virus fragment insertion in fowlpox virus of field strains.
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Jan, Sun-Rong, and 詹孫戎. "Light Emission from 6H-SiC/Ge and Strain Field Analysis of 3D IC/FinFET." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/27275305950619716580.
Full textAbstract:
博士國立臺灣大學
電子工程學研究所
100
There are two topics in this thesis including the light-emitting diodes and the strained Si techniques. The light-emitting diodes include the SiC MIS, the Ge MIS, and the Ge pn junction. The strained Si techniques include the strain induced by through Si vias and that induced by SiGe source/drain on FinFET. The electroluminescence of the SiC MIS is due to the donor and acceptor pairs instead of the band-edge transition. The electric field in the depletion assists the electrons and holes in hopping in the donor and acceptor levels to enhance the emission intensity, respectively. The dislocation of the Ge-on-Si leads to the defect levels reducing the indirect band-edge emission of the photoluminescence. The electroluminescence of the Ge pn junction and the Ge MIS is from the Ge bulk and the oxide/Ge interface, respectively. The roughness scattering at the oxide/Ge interface can conserve the momentum and enhance the indirect band-edge emission. The process temperature of the through Si vias from 200 oC cooling down to the room temperature with the larger coefficient of thermal expansion of the Cu than that of the Si leads to the strain. The strains along the radial direction and the angular direction are tensile and compressive, respectively. The current directions of the nMOS and pMOS favor to be parallel and vertical to the line of the through Si via III centers, respectively. The placement of through Si vias in a hexagon and in a circle can reduce the area of the keep-out zone. The relaxed surface boundary condition is applied suitably for the SiGe source/drain on the FinFET. There is the most compressive strain near the source/drain regions. The wrapped SiGe source/drain leads to more compressive strain than that by replaced one.
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Hsu, Ting Ting, and 許婷婷. "A Field Survey, Phylogenic Analysis and Infectious Clone Construction of Papaya leaf-distortion mosaic virus Taiwan Strain." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/71725075663493961059.
Full textAbstract:
碩士大葉大學
分子生物科技學系碩士班
98
Papaya ringspot virus (PRSV) causes the most economy loss in papaya production of Taiwan. Recently, the Papaya leaf-distortion mosaic virus (PLDMV) was also found. The infection rate of both viruses on papaya are uncertain. In this study, we investigated the PRSV and PLDMV distribution in Taiwan. Total 768 samples of papaya were collected from net-houses and field in papaya growth area, including MiaoLi, Changhua, Yunlin, Nantou, Chia-yi, Tainan, Kaohsiung, Pingtung, Taitung, and Hualien. According to Enzyme-Linked Immunosorbent Assay (ELISA), 53% of samples were only infected with PRSV, 4% were only infected with PLDMV, 17% were co-infected with PRSV and PLDMV, and 30% were undetectable. Multiplex RT-PCR for the specific detection of PRSV and PLDMV was used to identify the ELISA uncertain samples. The amplified DNA fragments of 378 bp and 564 bp indicated the infection of PRSV and PLDMV, respectively. The coat protein genes of 15 PLDMV samples that amplified by RT-PCR were further cloned. Sequence analysis of these CP genes showed 97.7 to 99.7% of nucleotide identities with each other, and 94.9-99% identity with other Taiwan isolates（TW-KS, TW-DL, and TW-TD. Moreover, these CP genes showed 93.7-95.2% identity with Japan strain（J56P and J179P）and much lower sequence identity（85.1-86.4%）with J199C strain which only infected cucurbit specise. Phylogenetic tree of 15 PLDMV CP gene is shown in differen clade of TW-TD、TW-KS and Japan isolates. To determine if the PLDMV-P Taiwan isolates could infect cucumber plants, two PLDMV isolates were inoculated into Cucumis metuliferus Acc.2459 and Cucumis sativus and the infectivity of the virus was detected by ELISA and western blotting analysis. Only 8.8% of symptomless C. metuliferus showed PLDMV infection. In previous study, the full-length PLDMV DL sequence was complete except for the nucleotides near the 5' end. 5'RACE was performed to obtain the 5'end sequence. Comparison of the full-length sequence of DL isolate with PLDMV TW-KS and J56P showed 94.5% and 94.6% of nucleotide identity, respectively. When comparing with the 5'UTR region, the identity to PLDMV TW-KS and J56P was 87.4% and 84.4%, respectively. With the PLDMV-DL complete sequence, an infectious transcript can be constructed. Seven PLDMV clones, including p35S-5'426, pPL5'-2764, pPL2680NarI-4361, pPL4247-6604, pPL5761-8298, pPL8150-9810, and pPL9528-3'NotI, with overlapping DNA fragments to each other were obtained by RT-PCR. These PLDMV DNA fragments were used to replace the sequence in 35S-PRSV infectious clone. A plasmid p35SPL2711-HA-9779NotI was obtained that contained the 35S promoter sequence followed by the 5'end of PLDMV nt 1 to 2711 and the 3'end of nt 9779 to the poly(A) tail. Finally, by introducing the PLDMV DNA fragment of nt 2680 to 9810 into p35SPL2711-HA-9779NotI, the full-length genomic sequence of PLDMV will be complete.
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Kara, Pravesh Deepak. "Determination and analysis of the complete genome sequences of a vaccine strain and field isolate of Lumpy Skin Disease Virus (LSDV)." Diss., 2003. http://hdl.handle.net/2263/25780.
Full textAbstract:
In this study, the genomes of both the attenuated South African lumpy skin disease virus (LSDV) Neethling vaccine strain (LW) and a virulent field isolate from a recent outbreak namely the South African lumpy skin disease virus (LSDV) Neethling Warmbaths isolate (LD) have been cloned, sequenced and analysed. The genomic sequences of the South African LSDV Neethling Warmbaths isolate (LD) and the South African LSDV Neethling vaccine strain (LW), were compared to each other. The virulent South African isolate, LD was also compared to the previously sequenced virulent LSDV Neethling strain 2490 (LK), to determine molecular differences. The LSDV genome is approximately 150 kbp in size and consists of 156 putative genes. Of the 156 potential encoded proteins of the virulent LSDV field isolates, the South African LSDV Neethling Warmbaths isolate (LD) and the LSDV Kenyan Neethling strain 2490 (LK), 120 were identical, 21 showed differences of a single amino acid, 7 showed two amino acid differences, while only one showed three amino acid differences. These were mostly found in the variable terminal regions. The LSDV Kenyan Neethling strain 2490 (LK) was isolated in Kenya in 1958 and than re-isolated in 1987 from lesions of an experimentally infected cow (Tulmanet al. 2001). The South African LSDV Neethling Warmbaths isolate (LD) was isolated from lesions of a severely infected calf in the Northern Province of the Republic of South Africa, on the farm Bothasvlei in 2001 (David Wallace, Biotechnology Division, Onderstepoort Veterinary Institute, Republic of South Africa; Personal communication, 2001). Considering the geographically distant African regions of the isolates, namely South Africa (LD) and Kenya (LK) as well as the time when these viruses were isolated, minimal genetic variation was observed thereby suggesting that lumpy skin disease virus is genetically stable. When the attenuated vaccine strain (L W) was compared with the South African field isolate LD, a total of 480 amino acid differences were observed in 121 of the 156 potential encoded proteins. These were again mainly in genes of the terminal regions and a number of these led to frameshifts that caused truncated open reading frames (ORFs) as well as deletions of up to nine amino acids and insertions of up to 42 amino acids. These modified open reading frames (ORFs) encode proteins that are involved in various aspects, such as the regulation of host immune responses [a soluble interferon (IFN)-gamma receptor, and an interleukin-l (IL-l) receptor-like protein], gene expression (mutT motif proteins), DNA repair (superoxide dismutase), host-range specificity (ankyrin-repeat protein, kelch-like proteins) including proteins with unassigned functions. These differences could lead to a reduction in immuno evasive mechanisms and virulence factors present in attenuated LSDV strains. At this stage, it is not possible to define which amino acid differences in particular are responsible for dramatic alterations in viral virulence. A good indication, however are differences occurring in functional domains. A mutation in a trans-membrane region, for example, could alter the levels of secretion of a protein involved in the regulation of the host immune response. We conclude that the attenuated effect is likely to be the sum of the altered phenotypes of the expressed proteins, although it is also likely that a few specific proteins carry more weight. Further studies to determine the functions of the relevant encoded gene products will hopefully confirm this. The molecular design of an effective vaccine is likely to be based on the strategic manipulation of such genes.Dissertation (MSc (Microbiology))--University of Pretoria, 2006.
Microbiology and Plant Pathology
unrestricted
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Huang, Pei-Chen, and 黃北辰. "Analysis and Investigation of Strain Engineering Utilized in 2D/3D Nano-scaled Germanium-based Metal Oxide Semiconductor Field Transistors Enabled by Column IV Semiconductor alloys." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/69394912930853497123.
Full textAbstract:
碩士中原大學
機械工程研究所
104
Currently, strain-engineering techniques are well established in Si-based metal–oxide semiconductor field-effect transistor (MOSFET)technology. To compensate for the drawback of device-size reduc-tion, germanium-substituted silicon is chosen as a channel material.Ge exhibits highly enhanced carrier mobility and it is regarded to be apromising channel material in a nano-scale MOSFET beyond the sub-22 nm technology node. This element has attracted considerable at-tention because of its potential to enhance the drive current of MOSFETsby replacing traditional strained Si-channel technology. Implanting Siatoms in the source/drain (S/D) region on the Ge substrate is a con-ventional method. Si and Ge atoms generate lattice mismatching,which improves device efficiency. Thus, this study adjusts the layout pattern of the device and usea 3D finite element model to simulate channel stress and mobility. Bycombining appropriate S/D stressors composed of Ge1 − x Six alloyswith the CESL at the considered intrinsic stress points, a significant en-hancement in the performance of tensile strained Ge-based nMOSFET can be acquired. Moreover, the strained GeSn alloy embedded into a Ge-based device is considered as a promising solution of next generation advanced devices. In contrast with Si, Ge, C in group IV semiconductor devices, GeSn alloy is indeed a novel material adopted in strained engineering. On the other hand, the arrangement of device layout also plays an important rule to influence device performance as S/D stressors are exerted. However, the analysis regarding comprehensive effects integrated GeSn stressors with the layout of that salient gate width extends across a dummy active diffused region (Dummy OD) is little. For this reason, a reliable device stress simulation is proposed and performed to explore the above-mentioned concerns under the vehicle consideration of a 20 nm Ge-based pMOSFET with a 100 nm gate width and a 100 nm dummy gate width. For the FinFETs layout design, the larger S/D region length and narrow channel length was suggested to enhance the longtidual stress of concerned channel.
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Jian, Jia-Hui, and 簡嘉慧. "Application of Taguchi Method and Grey Relational Analysis to Establish The Prediction Model on The Field Trial Factors of Bacillus amyloliquefaciens Strain A1 against Alternaria brassicicola." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/73568955807672351640.
Full textAbstract:
碩士國立高雄師範大學
生物科技系
103
There are several major factors affecting field trials. In the study, the impact factors of biopesticide wettable powders Bacillusamyloliquefaciens strain A1 is essential to understand as well as to set up a proper model in the field trials . In field trials bioagent products were tested by users in a “real life” setting (as opposed to testing under artificial laboratory conditions). Field trials are time-consuming and labour intensive which compare to laboratory trials. Field trials are normally applied when a final prototype is available, or a complete product is to be evaluated. First, in order to study the model closer to the field trials, the relationship betweenbiological and non-biological factors that we use leaf-disk assay to developed for disease assessment of Cabbage leaf spot disease caused by Alternaria brassicicola The microbial model is established based on conditions in fields. The results of the leaf-disk assay were consistent and agree with that of whole plant assays in the field trials. We discussed UV, temperature, relative humidity, spreading agents, and pH value in leaf-disk assays. The relationships between factors are discussed in the study. However, the influence order of factors that affect the leaf disease severity and real field trials is studied and discuss by combining Taguchi method and grey relational analysis. Using Taguchi experimental design method of orthogonal tables for multiple factor combination test, then we use factor responding figure to explore the best combination of factors, to analyze the impact of the system. Finally ,we use gray relation theory GM (1,1) model : to evaluate system decisions before field trials. The predictive value of the model is close to the actual field trial. We can use the model in labortory experiments. Using the model to predict disease severity of Alternaria brassicicola which is at 26.18 % and the actual value is at 25.60 % . The result of this study is useful to field trials. Finally, we discussed Alternaria brassicicola spores Inhibition factors, and when spore concentration is at 108 CFU / mL, 40 mg / L ItuirnA, 160 mg/ L surfactin , non-UV, non-surfactant, and cultured for 24 hours. The inhibition rate can reach to 84.00%. A1 inhibited Alternaria brassicicola spores germinate, swelling and deformation of the spores, the spores can not germinate after deformation, after 96hr the spore died through the bursting cell.
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Chung, Hsiang-Hsien, and 鍾享顯. "EndoFEM Analysis on Stress/Strain Fields of Al6061-T6 SEN Specimen with Crack Open/Closure Mechanism." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/38335021349098049977.
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Li, Ming Chang, and 李明昌. "Application of pulsed-field gel electrophoresis and other molecular typing methods for analysis of streptococcus suis type II strains." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/25975778265607400247.
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陳金蘭. "Detedcion of the pigs infected by Classical Swine Feve(or Hog Cholera) virus of fild strain using antibody analysis and Revers Transcriptase-PCR method." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/31304226986128480818.
Full textAbstract:
碩士國立中興大學
獸醫微生物學研究所
87
Fourty piglets, including 32 conventional and 8 SPF piglets, were divided into three groups. The first group was consisted of 10 conventional piglets. Five of them were vaccinated with one dose of LPC vaccine at 6 weeks old and the other five piglets were vaccinated two times at 6 and 9 weeks old. The second group, consisted of 10 conventional and 4 SPF piglets, were divided into two subgroups. Each subgroup contained 5 conventional and 2 SPF piglets. One subgroup was vaccinated at 6 weeks old, and the other subgroup was vaccinated two times at 6 and 9 weeks old. After vaccination, all this second group piglets were intramuscularly inoculated with the virulent ALD hog cholera virus at 11 weeks old. The third group was consisted of 12 conventional and 4 SPF piglets, in which 5 conventional and 2 SPF piglets were vaccinated at 6 weeks old and the other 5 conventional and 2 SPF piglets were vaccinated two times at 6 and 9 weeks old. Two conventional leftovers were unvaccinated, challenged at 11 weeks old, and housed with other vaccinated piglets of the third group for contact infection. Serum samples from vaccinated and unvaccinated animals were titrated with fluorescent antibody. The geometric means of serum neutralization (SN) titer from piglets vaccinated at 6 or 6 and 9 weeks old were 5.31X and 2.04X at 6 weeks old (prior to vaccination), and decreased to 0.87X and 1.89X at 9 weeks old (3 weeks post vaccination), respectively. Following the boost at 9 weeks old, the SN titer moved to 32X at 13 weeks old and reached peaks at the marketing time. However, the SN titers from one time vaccination animals reached peaks at 6 months old. The geometric means of SN titers from animals with one or two times vaccination following ALD challenge were 6.95 X and 3.24 X at 6 weeks old and decreased to basal levels at 9 weeks old, but it increased slightly at 10 weeks old and boosted by challenge, then maintained in high levels through the marketing time. For vaccinated and contact infection piglets, the geometric means of SN titers were 3.10 (log 2) and 4.38 (log 2) prior to contact infection, and it increased rapidly, then maintained in high levels through the marketing time. In SPF piglets, the SN titers were undetectable prior to vaccination, and boosted by vaccination and maintained in high levels through the marketing time . The SN titers from two unvaccinated piglets were undetectable and the animals died at 9th and 11th days following ALD challenge. Antibody titers test by ELISA with the (H) brand ELISA kits showed that the antibody inhibition values of each test group were below 30 prior to vaccination. There were no significant differences between one and two times vaccination. Antibody titers test with (W) brand ELISA kits indicated that the conventional piglets were positive, while SPF piglets were flatted. In additional, there were no significant differences between one and two time vaccination. Saliva and blood samples were collected from the ALD challenge animals and performed by RT-PCR to test the carrier status. The saliva samples, collected from each challenge group, were positive in RT-PCR at the fourth day post challenge. However, the saliva samples from vaccinated animals maintained undetectable through the test time.
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CHEN, KUAN-JEN, and 陳冠任. "A Preliminary Study of the Flow Field in the Central Taiwan Strait -Case of the Analysis of Observation by Miaoli Cutter ADCP of R.O.C Coast Guard." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/3kk72y.
Full textAbstract:
碩士中央警察大學
水上警察研究所
107
The Taiwan Strait links the East China Sea and the South China Sea. It is an important passage for exchange of materials between these two marginal seas. Due to its geographical location, the in situ observational data of the flow field in the central Taiwan Strait are quite scarce, especially during the winter months. In order to get a better understanding of the flow field in the central Taiwan Strait, this study employs the data observed by the ADCP of the Miaoli Cutter in winter and the concurrent wind speed data from the Central Weather Bureau to examine the features of the flow field in winter. Both the historical literature and the data obtained in this study indicate that the semidiurnal tide is quite strong in this region. Therefore we apply the TPXO barotropic tidal model to remove the tidal current, compare with the subtidal current obtained by harmonic analysis, and then conduct the wavelet transform to explore the correlation between local wind and subtidal current. On the west side of the Taiwan Strait, the presence of China Coastal Current is confirmed in the vicinity of Wuqiu. We also delineate the evolution of China Coastal Current across the Taiwan Strait using satellite-derived sea-surface-temperature images. Overall, the results obtained in this study are very close to those of previous researchers. We believe that if we can collect more accurate ocean current data in the future, it will definitely improve the efficiency of the Coast Guard in carrying out the search and rescue missions. Moreover, it will be beneficial to marine environmental conservation, oil pollution response, and prediction of marine waste drift. keyword：flow field、Coast Guard、Miaoli Cutter、ADCP
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YaFenLiu and 劉雅芬. "Genome size estimation of Lactobacillus reuteri DSM20016 and distribution analysis of L. reuteri strains isolated from gastrointestinal tract of chickens in Taiwan by pulsed-field gel electrophoresis." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/51842578784113823356.
Full textAbstract:
碩士國立中興大學
獸醫微生物學研究所
90
Lactobacillus reuteri, being able to secrete a strong microbiciidal substance termed reuterin, has been found as a dominant bacteria species in the gastrointestinal (GI) tract of animals. The type strain Lactobacillus reuteri DSM20016 was initially isolated from human feces by Lerche and Reuter in 1976. In this study, the pulsed-field gel electrophoresis (PFGE) technique was employed to estimate the genome size of Lactobacillus reuteri DSM20016. Through summation of the total DNA fragments generated by the restriction of L. reuteri chromosome with SgfI, NotI and FseI, respectively, the genome size was estimated as about 2.1Mb. Subsequently, the PFGE technique was used to study the distribution of L. reuteri strains in GI tract of chickens. Several important results were obtained as follows: (1) a total of 56 SgfI-PFGE types were identified from 72 strains of L. reuteri isolated from versatile chickens including native, broiler, and layer breeds, indicating a clonal polymorphysm of this species in Taiwan´s chicken, (2) some SgfI-PFGE types, including L3, L8, L14, M1, E5, E13, and E21 were found to exist in many chickens of a the same farm, simultaneously, (3) some SgfI-PFGE types, including M2, M4, and E8 were also found to exist in some chickens of different farms, (4) among the 5 GI portions investigated in this study, some SgfI-PFGE types such as L14, M1, and E21 were found to be capble of existing on more 2 GI portions, especially of the type L14 were isolated from the total 5 GI portions, simultaneously. This is the first evidence indcating the co-existance of a single PFGE type on 5 portions of GI tract.
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Lai, Chieh-hsien, and 賴潔賢. "Pulsed-field gel electrophoresis analysis, toxin types and plasmid profile for Methicillin resistant Staphylococcus aureus strains isolated in Taiwan from food-poisoning cases and clinical samples between 1998-2003." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/54220291423056084969.
Full textAbstract:
碩士大葉大學
生物產業科技學系
93
ABSTRACT Methicillin-resistant Staphylococcus aureus (MRSA) is one of the major pathogens infected in community hospitals, and the incidence of MRSA strains is increasing and becomes a common problem among the hospitals in Taiwan recently. In this study, the polymer chain reaction (PCR) was used to detect the mecA resistant gene, and the Sma I restriction enzyme was used to digest the chromosomal DNA of MRSA. In addition, the plasmid profile and the pulsed field gel electrophoresis (PFGE) analysis were used to investigate the distribution of the toxin types for MRSA strains from Veterinary General Hospital (VGH) in Taichung and Center for Disease Control, Taiwan, ROC. (TCDC), and trace the MRSA infection in the hospitals. The PCR results showed that 45 (59.21 %) clinical strains from VGH and 23 (16.3 %) human S. aureus strains from food-poisoning cases provided by TCDC possessed mecA resistant gene. The ratio of MRSA strains from hospitals was higher than that from food-poisoning cases. As for the distribution for enterotoxin types, it was found that the major enterotoxin types for the strains from hospitals and food-poisoning cases were the enterotoxin A and B, respectively. From the results of the plasmid profiles for MRSA strains, totally 29 distinct plasmid types were found. Of them, no co-shared types were found in the isolates from hospitals and food-poisoning cases. The PFGE results showed that 18 PFGE types were found in the 68 MRSA strains from hospitals and food-poisoning cases in 2003, and the major types for the strains from hospitals were different from those for the strains from food-poisoning cases. In addition, the clinical strains isolated between 1998 and 2003 were found high similarity in PFGE type. The results of this study reveal that the MRSA with same PFGE type still prevail in hospitals.