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781.
Supplier selection is a complex multi-criteria problem including both quantitative and qualitative factors. In order to select the best suppliers it is necessary to make a trade-off between these factors, some of which may be in conflict and may also be uncertain. In this problem if suppliers have capacity or other different constraints, two problems will exist: which suppliers are best and how much should be purchased from each selected supplier.In this paper an integrated approach of multi-attribute utility theory (MAUT) and linear programming (LP) is proposed for rating and choosing the best suppliers and defining the optimum order quantities among selected ones in order to maximize total additive utility. A numerical example is proposed to illustrate an application of the proposed method.  相似文献   
782.
新农村建设与民族传统体育的发展研究   总被引:4,自引:0,他引:4  
农村民族传统体育的良好发展是社会主义新农村建设的主要内容之一。文章对开展民族传统体育在新农村体育建设中重要性和可行性进行了分析,提出了发展民族传统体育的相关策略,希望为新农村体育建设提供理论依据。  相似文献   
783.
In this letter, the existence and the global exponential stability of piecewise pseudo almost periodic solutions (PAPT) for bidirectional associative memory neural networks (BAMNNs) with time-varying delay in leakage (or forgetting) terms and impulsive are investigated by applying contraction mapping fixed point theorem, the exponential dichotomy of linear differential equations and differential inequality techniques. Furthermore, we give an explanatory example to illustrate the efficiency of the theoretical predictions.  相似文献   
784.
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   
785.
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?D’ values were moderately correlated (adj. R2?=?0.60, p?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   
786.
This paper concerns the simultaneous fault detection and control (SFDC) problem for a class of nonlinear stochastic switched systems with time-varying state delay and parameter uncertainties. The switching signal of detector/controller unit (DCU) is assumed to be with switching delay, which results in the asynchronous switching between the subsystems and DCU. By constructing a switching strategy depending on the state and switching delays, new sufficient conditions expressed by a set of linear matrix inequalities (LMIs) is derived to design DCU gains. This problem is formulated as an H optimization problem and both mean square exponential stability and fault detection of augmented system are considered. A numerical example is finally exploited to verify the effectiveness and potential of the achieved scheme.  相似文献   
787.
Carboplatin is a chemotherapeutic agent used against various malignancies such as ovarian carcinoma. The aim of this study is to improve the therapeutic efficacy of carboplatin using pegylated liposomal nanocarriers. Nanoparticles were synthesized using thin film hydration technique and characterized for shape morphology, particle size, zeta potential and drug-release properties. In the next step, A2780S and A2780CP ovarian cancer cell lines were used to determine the efficacy of nanodrug by MTT assay. The particle size and zeta potential of nanodrug were measured 244.3 ± 19.6 nm and ?22.9 ± 1.7 mV, respectively. High encapsulation capacity (78.6 ± 3.7 %) confirmed the efficiency of technique. The cytotoxicity results also showed that nanodrug compared to free drug improve the efficacy of carboplatin against both A2780S (P < 0.01) and A2780CP (P < 0.05) cell lines. In conclusion, the findings of our study suggested pegylated liposomal nanocarriers are proper for carboplatin delivery to ovarian cancer cell lines A2780S and A2780CP.  相似文献   
788.
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   
789.
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   
790.
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   
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