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1.
Mathematical models are an approximate of physical systems and design procedures are only complete when modeling errors have been quantified. Uncertainties are incorporated in design procedure to compensate such discrepancies and to add robustness. This paper investigates the design problem of parameter-dependent switched observers for polytopic uncertain switched systems. State-space model is considered subject to time-varying uncertainties, and designated observer gains ensuring stability of overall system are also parameter-dependent. Synthesis procedure is demonstrated by employing ?∞ performance criteria which has become a standard for robust system design against external disturbances. This investigation is carried out in the framework of finite-time stability (FTS) and finite-time boundedness (FTB) which is the focus of researchers recently because of its apparent practical significance, especially after the emergent utilization of linear matrix inequalities. 相似文献
2.
Khalid M Yang WJ Kishwar N Rajput ZI Arijo AG 《Journal of Zhejiang University. Science. B》2006,7(6):459-466
This study is aimed at identifying and determining the percentage of occurrence frequency of cellulose decomposing soil fungi. The soil samples were inoculated into culture plates prepared in Sabouraud medium under sterilized conditions and incubated at 30 ℃ for 4 to 7 d. The identified fungal species were incubated in self-designed cellulose medium for testing their cellulolytic ability. Forty-two species, including2 nova species, representing sixteen genera showed growth and sporulation in the cellulose medium. Most of the isolated species were from genus Aspergillus and Penicillium. Aspergillus niger and Mucor hiemalis showed highest occurrence frequency （45% and 36% respectively）, as these species were collected from about 80% of soil samples. Being agar free and cheaper, the new fungal medium designed showed results equivalent to Sabouraud medium. 相似文献
3.
Muhammad Zubair Iqbal 《广播与电子媒介杂志》2017,61(2):449-466
The media-terrorism nexus needs further exploration. This article is a qualitative analysis of the coverage of London Attacks, 2005 by the British TV news channels. It aims to investigate and to empirically ascertain the veracity of the media-terrorism-symbiotic-relationship notion. The research draws a comparison with a similar study of the coverage of Mumbai attacks, 2008 and maintains that when the terrorist event happens on British soil, the symbiotic relationship theory is not verified completely. It concludes that British TV news channels, while reporting the home event of terrorism, do not overly focus on the theme of awe and terror. Instead, they are more responsible, careful, and nationalistic while covering the events of terrorism. 相似文献
4.
Hamdi Echeikh Ramzi Trabelsi Atif Iqbal Med Faouzi Mimouni 《Journal of The Franklin Institute》2018,355(5):2112-2141
High performance multiphase motor drive requires precise knowledge of the state quantities and the machine parameters. Access to these state quantities is through measurement using sensors whose accuracy is paramount to achieve the performance level required by industrial applications. However, the problems of the parameters variations, inaccessibility to the measurement of some states, no-observability of the machine in some regions, the cost of the sensors and their lack of precision, make this very difficult task. To address these problems, it is necessary to resort to soft sensors through the design of observers and estimators. In multiphase induction motor drive, the observation problem arises especially for rotor flux that is not accessible for measurement. About the parameters variations, the rotor resistance and the stator resistance are the most critical parameters of the machine because their influence is crucial for the control and observation. The change in the resistances can be as large as 40–50% of the rated value, which may affect the control adversely. This paper develops a new structure of an adaptive sliding mode observer based on an online estimation of the rotor resistance value in order to avoid the effect of its variation in the rotor flux oriented control. The results show convergent (the errors in the transient and steady states are 5% and 1%, respectively) behavior of the drive using the proposed control scheme for large rotor resistance variation under loaded condition. The stability of the drive is proved using Lyapunov criteria. The simulation results are validated using real time implementation. 相似文献
5.
The Effect of Executive Function on Biological Reasoning in Young Children: An Individual Differences Study 总被引：1，自引：0，他引：1
There is substantial variance in the age at which children construct and deploy their first explicit theory of biology. This study tests the hypothesis that this variance is due, at least in part, to individual differences in their executive function (EF) abilities. A group of 79 boys and girls aged 5–7 years (with a mean age of 6½ years) were presented with two test batteries: (a) a biology battery that probed their understanding of life, death, and body functions and (b) an EF battery that tested working memory, inhibition, and set‐shifting skills. Individuals' EF scores significantly predict their biology scores, even after controlling for age and verbal IQ. 相似文献
6.
AbstractDrawing on data from a project exploring children's and adults’ friendships across social class and ethnic difference, this paper focuses on the enactment of national and institutional policy around children’s friendships as realized in three primary schools in diverse urban areas in London. Through a focus on the way in which social and emotional learning (SEL) and teachers’ understandings of children’s friendships seek to govern children’s friendship behaviours, we turn to Foucault’s work to explore how power shapes relations between policy frameworks and teachers’ practices, and between those who teach and those who are taught. We discuss the disciplinary potential of SEL and teachers’ ‘common sense’ understandings of children’s friendships, but conclude by noting possibilities for teachers to create spaces in which all children can safely explore the nature of friendships. 相似文献
7.
INTRODUCTION Parasitic diseases is a global problem and con-sidered as a major obstacle in the health and productperformance of animals. These may be due toendo-parasites that live inside the body, orecto-parasites such as ticks, mites, flies, fleas, midges,etc., which attack the body surface. Amongecto-parasites, ticks are very important and harmfulblood sucking external parasites of mammals, birdsand reptiles throughout the world (Furman and Loo-mis, 1984). The medical and economic im… 相似文献
8.
Mamuna Iqbal Usman Awan Salman Asghar 《The International Journal of Art & Design Education》2023,42(2):327-346
This study seeks to explore the impact of social upbringing on architectural learning. The theory of “habitus” helps to understand how students’ personality dispositions might affect the way they approach learning in the “field” of architectural education. The notions of learning approaches and knowledge codes in literature are used to develop a framework for the study that helps to explore the field of architectural education. It is a qualitative study, conducted through semi-structured interviews with 44 students in 10 architecture schools in Pakistan. Interviews explored students’ habitus as well as their learning approaches, later explored through the framework developed in the study. Interviews are transcribed and coded using Nvivo 12. A detailed analysis explores the connection between habitus and learning approaches and finds out that habitus plays a major role in determining the way students approach learning in Architecture, with most cultivated habitus students showing a deep learning approach. 相似文献
9.
RAJPUT Zahid Iqbal HU Song-hua XIAO Chen-wen ARIJO Abdullah G. 《Journal of Zhejiang University. Science. B》2007,8(3)
Vaccines require optimal adjuvants including immunopotentiator and delivery systems to offer long term protection from infectious diseases in animals and man. Initially it was believed that adjuvants are responsible for promoting strong and sustainable antibody responses. Now it has been shown that adjuvants influence the isotype and avidity of antibody and also affect the properties of cell-mediated immunity. Mostly oil emulsions, lipopolysaccharides, polymers, saponins, liposomes, cytokines,ISCOMs (immunostimulating complexes), Freund's complete adjuvant, Freund's incomplete adjuvant, alums, bacterial toxins etc.,are common adjuvants under investigation. Saponin based adjuvants have the ability to stimulate the cell mediated immune system as well as to enhance antibody production and have the advantage that only a low dose is needed for adjuvant activity. In the present study the importance of adjuvants, their role and the effect of saponin in immune system is reviewed. 相似文献
10.
Current research indicates that instructors find support for their teaching via membership in small social networks. The present study was conducted to further our understanding of these networks by looking specifically at the perceptions network members hold of each other in terms of similarity of beliefs and the value of their interactions. Results indicate that participants were more likely to perceive high rather than low similarity of beliefs with others in their network, and value was positively associated with perceived similarity. Implications for teaching practice and the work of educational developers are discussed. 相似文献