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Fault detection and diagnosis are important issues in process engineering. Hence, a considerable interest exists in this field now from industrial practitioners as well as academic researchers, as opposed to 30 years ago. The literature on process fault diagnosis, ranging from analytical methods to artificial intelligence and statistical approaches, is largely widespread. In this paper, the modeling of the real process is known, and the state-space representation is used. The properties of the Finite Memory Observer (FMO) are studied from a global point of view for the class of linear time-varying (LTV) systems with stochastic noises. The FMO performances are framed by the study of their properties, and that of their influences on diagnosis results. Fundamentally, the generation of residuals is an essential procedure in diagnosis. So, the determination of the optimal window length of the observer is resolved, and the generation of residuals for diagnosis completed. In the first part, the design of the observer and the residual generation are shown. The second part is devoted to the study of the sensitivity and robustness of the observer and of residuals generated from the observer. 相似文献
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Education is the backbone for the development of society. With the advent of technology, it is becoming necessary and being used for the advancement of society. Technology is being used for education as being used in other important fields of life. Usage of technology for education can play a big part in bringing improvement in education For this purpose, this research aims to explore the usage and effects of technology for education. While using the survey method, a questionnaire was constructed for data collection. The sample of the study consists of graduate and postgraduate students from both ODL and regular universities and the sample size would be of 300 respondents (150 from each type of university) who were selected by using simple random sampling. The present study concluded that technology is widely used by both regular and ODL students. This study further concluded that ODL students are more dependent on technology as compared to regular students. 相似文献
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The behavioural modifications that accompany Ramadan intermittent fasting (RIF) are usually associated with some alterations in the metabolic, physiological, and psychological responses of athletes that may affect sport performance. Muslim athletes who are required to train and/or compete during the month-long, diurnal fast must adopt coping strategies that allow them to maintain physical fitness and motivation if they are to perform at the highest level. This updated review aims to present the current state of knowledge of the effects of RIF on training and performance, focusing on key-factors that contribute to the effects of Ramadan on exercise performance: energy restriction, sleep deprivation, circadian rhythm perturbation, dehydration, and alterations in the training load. The available literature contain few studies that have examined the effects of RIF on physical performance in athletes and, to date, the results are inconclusive, so the effects of RIF on competition outcomes are not at present wholly understood. The diverse findings probably indicate individual differences in the adaptability and self-generated coping strategies of athletes during fasting and training. However, the results of the small number of well-controlled studies that have examined the effects of Ramadan on athletic performance suggest that few aspects of physical fitness are negatively affected, and where decrements are observed these are usually modest. Subjective feelings of fatigue and other mood indicators are often cited as implying additional stress on the athlete throughout Ramadan, but most studies show that these factors may not result in decreases in performance and that perceived exercise intensity is unlikely to increase to any significant degree. Current evidence from good, well-controlled research supports the conclusion that athletes who maintain their total energy and macronutrient intake, training load, body composition, and sleep length and quality are unlikely to suffer any substantial decrements in performance during Ramadan. Further research is required to determine the effect of RIF on the most challenging events or exercise protocols and on elite athletes competing in extreme environments. 相似文献
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The Muslim athlete, whether living in a Muslim majority country or in a non-Muslim country, face unique challenges to faithfully follow one of the pillars of their faith - Ramadan - while attempting to maintain their participation in sports training and competition. There are conflicting reports on the effects of Ramadan on fitness and physical performance in general and in football in particular. In general, the impact of a brief daytime fast has minor effects on health or factors of physical fitness. Add physical training and now a new set of barriers to both performance and the observance of Ramadan begin to interact. Practising athletes have worked out strategies to cope with the rigors of Ramadan; strategies that have both physical (training modifications, dietary habits, rest and recovery) and emotional (patience, emotional preparations) domains. Carefully blending strategies like these can help the football player be true to their faith and follow the tenants of Ramadan hopefully, with a minimum of impact on their physical performance. In this context, science can help coaches improve their training plans and educate players with respect to the challenges presented by Ramadan to all levels of sports participation. 相似文献
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Many of the socio-cultural lifestyle and dietary changes that take place during Ramadan may affect the risk of injury in athletes, but little evidence is available. The aim of the present study was to examine the effects over two consecutive years of the holy month of Ramadan on injury rates in 42 professional players of a Tunisian top-level professional soccer team. Players were retrospectively organized into fasting and non-fasting groups and monitored for 3 months: 4 weeks before Ramadan, during the month of Ramadan (4 weeks), and 4 weeks after Ramadan each year. During Ramadan, training started at 22.00 h. The circumstances (training/match) and mechanism of injury (traumatic/overuse) were recorded. No significant differences between the three periods were observed for weekly mean training load, training strain, training duration, and Hooper's Index (quality of sleep, and quantities of stress, delayed-onset muscle soreness, and fatigue). Compared with non-fasting players, fasters had a lower (P < 0.05) Hooper's Index and stress during and after Ramadan. No significant difference in injury rates was observed between fasting and non-fasting players. Nevertheless, the rates of non-contact (6.8 vs. 0.6 and 1.1) and training overuse (5.6 vs. 0.6 and 0.5) injuries were significantly higher in fasting players during the month of Ramadan than before or after Ramadan. In conclusion, Ramadan, along with the corresponding changes in nutritional habits, sleeping schedule, and socio-cultural and religious events, significantly increased overuse and non-contact injuries in fasting players despite the fact that the training load, strain, and duration were maintained. 相似文献
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No one would disagree that scientific research has been unethical—even criminal—at times. Institutional review boards (IRBs) play a fundamental role in protecting people from unethical criminological research. At the same time, IRBs, as social entities, are subject to a wide range of influences that may affect their decisions regarding the ethicality of research. This research note draws on the paradigm of pure sociology and the logic underpinning Black’s theory of law to propose a preliminary theory of IRBs’ (dis)approval of research. Specifically, it suggests that IRBs apply less social control to criminological research involving higher status researchers and lower status research participants and, therefore, those persons are more often involved in research. The paper concludes with theoretically situated, practical advice for how (1) IRBs can reduce their discrimination, and (2) criminological researchers can reduce IRBs’ disapproval of their projects and thereby increase their research output. 相似文献