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Synchronní reluktanční motory se pro svou relativně vysokou účinnost, robustnost a nízkou cenu stávají stále populárnější alternativou velmi rozšířených asynchronních motorů. Snaha o využití výhodných vlastností bezsnímačového řízení, a dosažení co nejvyšší účinnost jejich provozu, je však komplikována jejich výraznou nelinearitou způsobenou saturací magnetického obvodu. Úvod této práce je věnován popisu matematicko-fyzikálního modelu SynRM a přehledu existujících moderních algoritmů výkonově-optimálního bezsnímačového řízení. Jádrem práce je pak představení estimátoru stavů a parameterů SynRM postaveného na novém přístupu k měření a využití fázových reluktancí. Klíčovými prvky algoritmu jsou nová metodologie měření fázových reluktancí, spínací PWM schéma jež umožňuje snížit spínací ztráty a měřit fázové reluktance od nulových otáček, a nakonec integrace těchto měření s matematickým modelem SynRM s pomocí rozšířeného Kalmánova filtru. Experimentální část práce pak diskutuje výsledky reálných měření s navrženým algoritmem a vybranými současnými algoritmy., Synchronous reluctance motors are becoming a more and more popular alternative to the AC induction machine for their relatively high power efficiency, low cost, and high robustness. Full utilization of benefits of sensorless control and high power efficiency are being complicated by non-linearities of the motor, especially magnetic saturation. The beginning of this work is dedicated to an inference of the mathematical-physical model of SynRM and an overview of existing state-of-the-art sensorless power-optimal algorithms. The core of this work is then the introduction of the SynRM state and parameter estimator, which is based on a new approach to measurement and utilization of phase reluctances. The key elements of the algorithm are a new methodology for measuring phase reluctances, a PWM switching scheme that allows to reduce switching losses and to measure phase reluctances from zero speed, and finally the integration of these measurements with the SynRM mathematical model using extended Kalman filter. The experimental part of the thesis then discusses the real measurement results obtained with the proposed algorithms and several selected state-of-the-art algorithms.

L’article propose une réflexion théorique fondée sur des travaux empiriques menés en Amérique latine et en Chine visant à identifier et caractériser l’apprentissage technologique des entreprises. Nous rappelons les différentes conceptions de l’apprentissage dans la littérature sur les entreprises et le travail et présentons une définition de l’apprentissage technologique. Abandonnant les perspectives fondées sur une caractérisation basée sur l’entreprise dans son ensemble, notre interprétation se démarque des travaux précédents en ce qu’elle propose de fixer la focale sur l’identification des activités technologiques à la fois internes et externes ainsi que sur les connaissances qualifiées de « techniques » qui les accompagnent, plutôt que sur la gestion ou les décisions économiques qui les concernent. Fonder ce point de vue permet un réexamen des questions concernant la mondialisation et l’irruption d’entreprises innovantes dans les pays émergents., Technological learning : beyond the shopwork and the enterprise This article proposes a theoretical reflection based on empirical investigations in Latin America and China in order to identify and characterize technological learning. After reviewing the literature on various approaches of learning in firms, we propose a definition of technological learning. Leaving aside the perspectives based on characterizations realized at the level of the firm, our interpretation differs from previous work in that it proposes to focus the analysis on the identification of internal and external technological activities and on joint knowledge qualified as « technical » rather than on management and commercial decision that target them. Grounding this view allows the re-examination of globalization and the appearance of innovative firms in emerging economies., El artículo propone une reflexión teórica basada en trabajos empíricos en América Latina y China cuyo objetivo estaba de identificar y medir el aprendizaje tecnológico de las empresas. Después de revisar la literatura sobre el aprendizaje en las empresas y el trabajo, proponemos nuestra definición del aprendizaje tecnológico. Nuestra interpretación se distingue de precedentes propuestas teóricas en lo que propone de centrar el análisis sobre las actividades internas y externas de los talleres productivos así como los conocimientos usualmente cualificados de « técnicos » en vez de la empresa en su conjunto o los conocimientos de gestión o las decisiones económicas. Este punto de vista permite re-examinar la globalización productiva y la aparición de empresas innovadoras en los países emergentes.

The UK micro/SME (known here as SME) retail sector is very important to the economic well being of the country. Its ability to generate jobs as well as income makes it a key part of the drive towards economic growth, and as such it is supported by government through a variety of initiatives. One initiative in 2003 aimed to energise and invigorate practitioners into using internet based technologies more fully in their business practices. This supported the widely held belief that the internet can and does enhance and improve business efficiency. It also suggests that SMEs were not fully engaging with the technology and that the government felt that it was not at the desirable level. This thesis looks at the issues surrounding technology acceptance for the SME and in particular internet adoption in the retail sector. This work explains technology acceptance and the main determinants and moderators connected with this in an organisational setting providing the practitioner with insight into why some technologies are embraced and others underutilised, or not adopted at all. Previous academic work in this area has tended to focus on the larger organisation. This thesis uses the technology acceptance literature to explore the situation of the SME. Through qualitative and quantitative research the specifics of the SME situation relating to technology acceptance are explored with the determinants and moderators being evaluated and changes made where appropriate. The specific internet based technology of online procurement is used to measure levels of acceptance and the issues relating to it. The result is an adapted model that better reflects the technology acceptance situation of the SME retail organisation. In the model three of the original constructs remain, however the moderators have been changed to reflect the SME and the relationships the constructs have with the moderators are also developed. As a new addition to the field it can be seen from the developed model t

Myalgic encephalomyelitis (ME) is a debilitating illness of unknown etiology characterized by neurocognitive dysfunction, inflammation, immune abnormalities and gastrointestinal distress. An increasing body of evidence suggests that disruptions in the gut may contribute to the induction of neuroinflammation. Therefore, reports of human endogenous retroviral (HERV) expression in association with neuroinflammatory diseases prompted us to investigate the gut of individuals with ME for the presence of HERV proteins. In eight out of 12 individuals with ME, immunoreactivity to HERV proteins was observed in duodenal biopsies. In contrast, no immunoreactivity was detected in any of the eight controls. Immunoreactivity to HERV Gag and Env proteins was uniquely co-localized in hematopoietic cells expressing the C-type lectin receptor CLEC4C (CD303/BDCA2), the costimulatory marker CD86 and the class II major histocompatibility complex HLA-DR, consistent with plasmacytoid dendritic cells (pDCs). Although the significance of HERVs present in the pDCs of individuals with ME has yet to be determined, these data raise the possibility of an involvment of pDCs and HERVs in ME pathology. To our knowledge, this report describes the first direct association between pDCs and HERVs in human disease.

Myalgic encephalomyelitis (ME) is a debilitating illness of unknown etiology characterized by neurocognitive dysfunction, inflammation, immune abnormalities and gastrointestinal distress. An increasing body of evidence suggests that disruptions in the gut may contribute to the induction of neuroinflammation. Therefore, reports of human endogenous retroviral (HERV) expression in association with neuroinflammatory diseases prompted us to investigate the gut of individuals with ME for the presence of HERV proteins. In eight out of 12 individuals with ME, immunoreactivity to HERV proteins was observed in duodenal biopsies. In contrast, no immunoreactivity was detected in any of the eight controls. Immunoreactivity to HERV Gag and Env proteins was uniquely co-localized in hematopoietic cells expressing the C-type lectin receptor CLEC4C (CD303/BDCA2), the costimulatory marker CD86 and the class II major histocompatibility complex HLA-DR, consistent with plasmacytoid dendritic cells (pDCs). Although the significance of HERVs present in the pDCs of individuals with ME has yet to be determined, these data raise the possibility of an involvment of pDCs and HERVs in ME pathology. To our knowledge, this report describes the first direct association between pDCs and HERVs in human disease.

Synchronní reluktanční motory se pro svou relativně vysokou účinnost, robustnost a nízkou cenu stávají stále populárnější alternativou velmi rozšířených asynchronních motorů. Snaha o využití výhodných vlastností bezsnímačového řízení, a dosažení co nejvyšší účinnost jejich provozu, je však komplikována jejich výraznou nelinearitou způsobenou saturací magnetického obvodu. Úvod této práce je věnován popisu matematicko-fyzikálního modelu SynRM a přehledu existujících moderních algoritmů výkonově-optimálního bezsnímačového řízení. Jádrem práce je pak představení estimátoru stavů a parameterů SynRM postaveného na novém přístupu k měření a využití fázových reluktancí. Klíčovými prvky algoritmu jsou nová metodologie měření fázových reluktancí, spínací PWM schéma jež umožňuje snížit spínací ztráty a měřit fázové reluktance od nulových otáček, a nakonec integrace těchto měření s matematickým modelem SynRM s pomocí rozšířeného Kalmánova filtru. Experimentální část práce pak diskutuje výsledky reálných měření s navrženým algoritmem a vybranými současnými algoritmy., Synchronous reluctance motors are becoming a more and more popular alternative to the AC induction machine for their relatively high power efficiency, low cost, and high robustness. Full utilization of benefits of sensorless control and high power efficiency are being complicated by non-linearities of the motor, especially magnetic saturation. The beginning of this work is dedicated to an inference of the mathematical-physical model of SynRM and an overview of existing state-of-the-art sensorless power-optimal algorithms. The core of this work is then the introduction of the SynRM state and parameter estimator, which is based on a new approach to measurement and utilization of phase reluctances. The key elements of the algorithm are a new methodology for measuring phase reluctances, a PWM switching scheme that allows to reduce switching losses and to measure phase reluctances from zero speed, and finally the integration of these measurements with the SynRM mathematical model using extended Kalman filter. The experimental part of the thesis then discusses the real measurement results obtained with the proposed algorithms and several selected state-of-the-art algorithms.

Synchronní reluktanční motory se pro svou relativně vysokou účinnost, robustnost a nízkou cenu stávají stále populárnější alternativou velmi rozšířených asynchronních motorů. Snaha o využití výhodných vlastností bezsnímačového řízení, a dosažení co nejvyšší účinnost jejich provozu, je však komplikována jejich výraznou nelinearitou způsobenou saturací magnetického obvodu. Úvod této práce je věnován popisu matematicko-fyzikálního modelu SynRM a přehledu existujících moderních algoritmů výkonově-optimálního bezsnímačového řízení. Jádrem práce je pak představení estimátoru stavů a parameterů SynRM postaveného na novém přístupu k měření a využití fázových reluktancí. Klíčovými prvky algoritmu jsou nová metodologie měření fázových reluktancí, spínací PWM schéma jež umožňuje snížit spínací ztráty a měřit fázové reluktance od nulových otáček, a nakonec integrace těchto měření s matematickým modelem SynRM s pomocí rozšířeného Kalmánova filtru. Experimentální část práce pak diskutuje výsledky reálných měření s navrženým algoritmem a vybranými současnými algoritmy., Synchronous reluctance motors are becoming a more and more popular alternative to the AC induction machine for their relatively high power efficiency, low cost, and high robustness. Full utilization of benefits of sensorless control and high power efficiency are being complicated by non-linearities of the motor, especially magnetic saturation. The beginning of this work is dedicated to an inference of the mathematical-physical model of SynRM and an overview of existing state-of-the-art sensorless power-optimal algorithms. The core of this work is then the introduction of the SynRM state and parameter estimator, which is based on a new approach to measurement and utilization of phase reluctances. The key elements of the algorithm are a new methodology for measuring phase reluctances, a PWM switching scheme that allows to reduce switching losses and to measure phase reluctances from zero speed, and finally the integration of these measurements with the SynRM mathematical model using extended Kalman filter. The experimental part of the thesis then discusses the real measurement results obtained with the proposed algorithms and several selected state-of-the-art algorithms.

Synchronní reluktanční motory se pro svou relativně vysokou účinnost, robustnost a nízkou cenu stávají stále populárnější alternativou velmi rozšířených asynchronních motorů. Snaha o využití výhodných vlastností bezsnímačového řízení, a dosažení co nejvyšší účinnost jejich provozu, je však komplikována jejich výraznou nelinearitou způsobenou saturací magnetického obvodu. Úvod této práce je věnován popisu matematicko-fyzikálního modelu SynRM a přehledu existujících moderních algoritmů výkonově-optimálního bezsnímačového řízení. Jádrem práce je pak představení estimátoru stavů a parameterů SynRM postaveného na novém přístupu k měření a využití fázových reluktancí. Klíčovými prvky algoritmu jsou nová metodologie měření fázových reluktancí, spínací PWM schéma jež umožňuje snížit spínací ztráty a měřit fázové reluktance od nulových otáček, a nakonec integrace těchto měření s matematickým modelem SynRM s pomocí rozšířeného Kalmánova filtru. Experimentální část práce pak diskutuje výsledky reálných měření s navrženým algoritmem a vybranými současnými algoritmy., Synchronous reluctance motors are becoming a more and more popular alternative to the AC induction machine for their relatively high power efficiency, low cost, and high robustness. Full utilization of benefits of sensorless control and high power efficiency are being complicated by non-linearities of the motor, especially magnetic saturation. The beginning of this work is dedicated to an inference of the mathematical-physical model of SynRM and an overview of existing state-of-the-art sensorless power-optimal algorithms. The core of this work is then the introduction of the SynRM state and parameter estimator, which is based on a new approach to measurement and utilization of phase reluctances. The key elements of the algorithm are a new methodology for measuring phase reluctances, a PWM switching scheme that allows to reduce switching losses and to measure phase reluctances from zero speed, and finally the integration of these measurements with the SynRM mathematical model using extended Kalman filter. The experimental part of the thesis then discusses the real measurement results obtained with the proposed algorithms and several selected state-of-the-art algorithms.

The UK micro/SME (known here as SME) retail sector is very important to the economic well being of the country. Its ability to generate jobs as well as income makes it a key part of the drive towards economic growth, and as such it is supported by government through a variety of initiatives. One initiative in 2003 aimed to energise and invigorate practitioners into using internet based technologies more fully in their business practices. This supported the widely held belief that the internet can and does enhance and improve business efficiency. It also suggests that SMEs were not fully engaging with the technology and that the government felt that it was not at the desirable level. This thesis looks at the issues surrounding technology acceptance for the SME and in particular internet adoption in the retail sector. This work explains technology acceptance and the main determinants and moderators connected with this in an organisational setting providing the practitioner with insight into why some technologies are embraced and others underutilised, or not adopted at all. Previous academic work in this area has tended to focus on the larger organisation. This thesis uses the technology acceptance literature to explore the situation of the SME. Through qualitative and quantitative research the specifics of the SME situation relating to technology acceptance are explored with the determinants and moderators being evaluated and changes made where appropriate. The specific internet based technology of online procurement is used to measure levels of acceptance and the issues relating to it. The result is an adapted model that better reflects the technology acceptance situation of the SME retail organisation. In the model three of the original constructs remain, however the moderators have been changed to reflect the SME and the relationships the constructs have with the moderators are also developed. As a new addition to the field it can be seen from the developed model t

In the universities, Latex is one of the tool for producing Mathematical Expression in order to prepare scientific documents. Latex requires programming language to produce Mathematical Expression. I order to produce Mathematical Expressions (ME), it is also possible to write ME on electronic device and convert the handwritten ME to Latex. This requires techniques to recognise the handwritten ME. There are many possible techniques to recognise the handwriting mathematical expression such as Optical Character Recognition(OCR). The OCR is the most popular technology tool to read the handwriting text. However, the structure of the input data of electronic device is basically a set of strokes with a sequence order of X and Y coordinates. Hence, this project is related to the study of recognising the handwritten mathematical expression in Android mobile application. By adapting the Online Handwriting Recognition technique, the data values of handwritten ME will be processed, segmented and recognised through several techniques in order to convert the handwritten ME to typeset ME. This project also involves using the Support Vector Machine as the classification for mathematical symbol recognition. The performance evaluation of the Support Vector Machine has been carried out in this project. The conclusion and the future work have also been described in the last chapter of this dissertation.