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41.
网络应用涉及到社会的各个方面,已对人们的经济和文化生活产生重大影响。通过校园网络的组建,将实现办公、公文处理、日程安排、会议管理、档案管理、财务管理与报销、信息发布等方面实现信息共享和各种类型的无纸化办公等需求。网络组建设计要尽量简单化、结构化、模块化,这样既能节省资金投入,又能便于网络的管理与升级。本文对校园网络的组建采用自顶向下的设计方法进行研究和探索。  相似文献   
42.
Abstract

This study aims to show how the integration of passive and active learning approaches contributes towards the significant understanding of problems associated with sustainable development. To do this, a case study from the municipality of San Miguel de Achiutla in Oaxaca, Mexico, is used as a general method, with the specific procedure including an instrument based on secondary sources representing the passive learning phase, as well as an instrument created on the basis of primary sources, designed in relation to the active learning component. The passive learning phase enabled us to identify variables pertaining to the highly vulnerable dimensions of sustainable development, and to also detect areas in which there is a deficit of information, since not all data are available, while the active learning phase revealed the causes of vulnerability from the perspective of different agents, including those who experienced the issues directly. In view of the above, we conclude that rather than being exclusive, these two different approaches should in fact be complementary.  相似文献   
43.
En el campo del lenguaje y la lectoescritura, la renovación educativa parece estar situándose en la batalla por el diseño abierto y la evaluación informal. En este artículo se propone un modelo teórico para la lectoescritura flexible que pueda soportar las posibilidades que se abren y evitar los inconvenientes que amenazan a los actuales métodos informales de renovación a los que está dedicado el tema central de este número.  相似文献   
44.
First‐generation undergraduate students face challenging cross‐socioeconomic cultural transitions into college life. The authors compared first‐ and non‐first‐generation undergraduate students’ social support, posttraumatic stress, depression symptoms, and life satisfaction. First‐generation participants reported less social support from family and friends, more single‐event traumatic stress, less life satisfaction, and marginally more depression symptomatology than non‐first‐generation participants, but significant generation–gender interactions showed first‐generation women doing worse and first‐generation men doing better than others.  相似文献   
45.
This paper presents conditions to assure the exponential stability in probability for autonomous switching linear systems. The switching signal acting on the autonomous system produces intervals that follow independent, identically distributed stochastic processes—the stability then follows by verifying simple-to-check linear matrix inequalities.  相似文献   
46.
ABSTRACT

The recruitment of athletes with limited resources is a global problem in professional sports. In US Major League Baseball, the experience of the Oakland Athletics’ general manager in the last decade turned his “Moneyball” model into a synonym of quantitative analysis in the transfer market of baseball players. His strategy focused on hiring players with outstanding technical skills but relatively low market value. This study adapted this model to the framework of a multiple criteria decision aid (MCDA), by selecting undervalued players who have complementary abilities. The novelty here refers to the joint use of four algorithms explored by the composition of probabilistic preferences (CPP) (i.e., ranking, classification, dynamic evaluation and regularity analysis) and their application to soccer player performance evaluation. The new model analysed the recent transfer of a left-back soccer player to Europe. The results indicated 12 opportunities for better investment, among 32 left and right-back players considered. Two years later, the value of the same player was considerably lower. He played only five matches in the 2018–2019 season, without scoring or providing any assists. On the other hand, the players better classified by the CPP-MB model presented higher performances and market values.  相似文献   
47.
48.
In this study, the fibers of invasive species Agave americana L. and Ricinus communis L. were successfully used for the first time as new sources to produce cytocompatible and highly crystalline cellulose nanofibers. Cellulose nanofibers were obtained by two methods, based on either alkaline or acid hydrolysis. The morphology, chemical composition, and crystallinity of the obtained materials were characterized by scanning electron microscopy(SEM) together with energy-dispersive X-ray spectroscopy(EDX), dynamic light scattering(DLS), X-ray diffraction(XRD), and Fourier transform infrared(FTIR)spectroscopy. The crystallinity indexes(CIs) of the cellulose nanofibers extracted from A. americana and R. communis were very high(94.1% and 92.7%, respectively). Biological studies evaluating the cytotoxic effects of the prepared cellulose nanofibers on human embryonic kidney 293 T(HEK293 T) cells were also performed. The nanofibers obtained using the two different extraction methods were all shown to be cytocompatible in the concentration range assayed(i.e., 0-500 μg/mL). Our results showed that the nanocellulose extracted from A. americana and R. communis fibers has high potential as a new renewable green source of highly crystalline cellulose-based cytocompatible nanomaterials for biomedical applications.  相似文献   
49.
The use and development of analogical processes in learning to read in Spanish are presented. In the first experiment, the results show that children of 6 years old show analogical effects in reading pseudowords and that the magnitude of this effect is the same as with 10 years old children. However, it is found that children of 10 years old make many lexicalizations when reading pseudowords (about 50% of the items). In experiment 2 this finding is further analyzed. The results show that 9 years old children make more lexicalizations than adult control subjects do. It is suggested that the development of analogical procedures is a fast process (6 years old children already have done it), but that the precise control of lexical information over perceptual one is a later process.  相似文献   
50.
A Chebyshev collocation method, an expansion method, has been proposed in order to solve the systems of higher-order linear integro-differential equations. This method transforms the IDE system and the given conditions into the matrix equations via Chebyshev collocation points. By merging these results, a new system which corresponds to a system of linear algebraic equations is obtained. The solution of this system yields the Chebyshev coefficients of the solution function. Some numerical results are also given to illustrate the efficiency of the method. Moreover, this method is valid for the systems of differential and integral equations.  相似文献   
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