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711.
Yue-E Wang Ben Niu Bao-wei Wu Caiyun Wu Xue-Jun Xie 《Journal of The Franklin Institute》2018,355(5):2912-2931
We study the input-to-state stability (ISS) of switched nonlinear input delay systems under asynchronous switching. Our results apply to cases where some subsystems of the switched systems are not necessarily stable under the influence of input delay. By making a compromise among the matched-stable period, the matched-unstable period, and the unmatched period and allowing the increase of the Lyapunov–Krasovskii functional (LKF) on all the switching times, the extended stability criteria for switched delay systems in generally nonlinear setting are derived first. Then, we focus on switched nonlinear input delay systems where the presence of the input delay leads to the instability of some subsystems of it. By explicitly constructing input-to-state stable LKF, the sufficient conditions for ISS of switched nonlinear input delay systems under asynchronous switching are presented. Finally, two examples are given to illustrate the effectiveness of the proposed theory. 相似文献
712.
Lachlan J. G. Mitchell David B. Pyne Philo U. Saunders Ben Rattray 《European Journal of Sport Science》2018,18(3):307-314
Critical speed (CS) testing is useful in monitoring training in swimmers, however, completing a series of time trials (TTs) regularly is time-consuming. The 3-minute test may be a solution with positive initial findings. This investigation examined whether a modified 3-minute test (12?×?25?m) could assess CS and supra-CS distance capacity (D’) in swimmers. A series of 12?×?25?m intervals were completed unpaced at maximal effort, interspersed with 5?s rest periods. The model speed?=?a eb t?+?c was fitted to the data and integrated to calculate D’. The slowest two of the last four efforts were averaged to calculate CS. To assess reliability, 15 highly trained swimmers (9 females, 6 males) completed the 12?×?25?m twice within 72?h. Four measures were deemed reliable: peak velocity (0.01?m?s?1; 0.5%, typical error and % coefficient of variation), CS (0.02?m?s?1; 1.2%), D’ (1.22?m; 5.7%) and drop off % (0.70% points; 4.5%). To assess criterion validity, 21 swimmers (9 from reliability, 12 other) completed two competition races within 2 weeks of a 12?×?25?m in the same stroke. Traditional CS and D’ measures were calculated from competition performances (TT method). TT CS and 12?×?25?m CS were highly correlated (adj. R2?=?0.92, p?.001). D’ values were moderately correlated (adj. R2?=?0.60, p?.01). Two TTs may have been too few to estimate D’ accurately. The 12?×?25?m all-out swimming test is a reliable method for assessing CS and D’ in swimmers, however, the validity of D’ requires further investigation. 相似文献
713.
提出一个关于计算紧半代数集构成排列的0维Betti-数和1维Betti-数的算法.这个算法的复杂度为单指数复杂度. 相似文献
714.
With the introduction of clinical governance and the move towards evidence-based practice, there is a growing need to provide health professionals and patients, and the public, with high quality information. Developments in the health service have added weight and urgency to this need. The National electronic Library for Health (NeLH) has a key role to play in providing health professionals with a core knowledge base of accredited and evaluated information. The Pilot NeLH was launched in November and this article outlines the progress and achievements made during this time. The NeLH is based around a central website featuring core resources and links to commissioned specialist collections. Over 70 information resources, including bibliographic databases and full text publications, are accessible via the NeLH, which aims to act as a one-stop shop to support evidence-based decision-making. Much work has been undertaken on national procurement and licensing, particularly in partnership with National Health Service (NHS) libraries. Partnerships as a whole are crucial to ensure true seamless access for health professionals. Key partners include NHS libraries, NHS Direct Online and the electronic Library for Social Care. A short glossary is included for those readers less familiar with current health service developments in the UK. 相似文献
715.
Is sex between people with "mental retardation" [1] morally permissible and, if at all, under what conditions? This paper tries to answer this question, but only with regard to sex between biologically mature individuals with mild or moderate mental retardation. First, the concepts of "sexual activity" and mental retardation" are analysed briefly, which is challenging given the widely divergent and sometimes rather awkward definitions of these concepts. On the basis of this analysis, it is argued that the liberal principle of mutual consent, if taken as a necessary condition of permissible sex, has unacceptable consequences for people with mental retardation. Many forms of sex between them would be morally impermissible, given the fact that their limited powers of practical reasoning will often make valid consent well-nigh impossible. As an alternative to the liberal principle of permissible sex, conditions are specified that include the additional consent of caretakers. If people with mental retardation do not have the capacities of practical deliberation required for valid consent, care providers with mature reasoning powers should act as their substitutes. Finally, some important implications for the moral education of future care professionals are spelled out. 相似文献
716.
介绍了美国制定职业道德 ,特别是图书馆员职业道德的原则以及图书馆员职业道德内容。提出中国信息产业和图书情报从业人员道德准则的内容。图 1。表 2。参考文献 6。 相似文献
717.
以新时代党和国家领导人关于民族工作的重要论述以及《新疆的文化保护与发展》《新疆的若干历史问题》白皮书为指导,研究认为,对中华母体体育文化的认识有待提高、文化属性的缺位相对明显、不良宗教文化的附着存在较大可能以及游牧文化的离散成为常态,是新疆少数民族传统体育发展过程中面临的特殊性文化困境。上述文化困境产生的主要原因在于:在新疆少数民族传统体育发展中,存在着机械性"华夷之辩"观念的浸入、对文化属性认知的不足、文化差异的过度强调、现代化进程中的文化迷失等四方面问题。破解新疆少数民族传统体育发展中的文化困境,需要从转变思想观念,给予新疆少数民族传统体育准确定位;加强多方引导,深化对新疆少数民族传统体育文化属性的认识;树立明确观念,客观认识新疆少数民族传统体育中的文化差异;推进体育文旅,促进新疆少数民族传统体育文化和产业的融合发展等四方面展开。 相似文献
718.
719.
720.
学校体育产业化的理论内涵和模式特征研究 总被引:6,自引:0,他引:6
在文献资料、调查访问的基础上,归纳整理出中国学校体育走产业化道路的发展现状和模式特征,为学校体育与市场经济相结合提供参考依据. 相似文献