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991.
按类招生是一种新的招生和人才培养模式,是高等学校深化教育教学改革的一项重要措施,体现了“以人为本”的教育理念,对培养具有创造能力、应变能力的高素质复合型人才方面,无疑具有其极大的优势,但是,作为一种新的培养模式,同样也存在许多问题。招生方式的改革只是表面的东西,更重要的是教育体制的革新。 相似文献
992.
胡孝根 《延边大学东疆学刊》2006,23(3):86-89
柏拉图认为,理想国家的构建是一个庞大的系统工程,而诗教是其中的重要一环。只有高度重视诗人的作用,全方位发挥诗歌的审美、教育和政治功能,用“好的故事”教育儿童,培养合格的统治人才,才能为理想国家的建立奠定坚实基础。 相似文献
993.
994.
Weifan Wang Tingting Wu Xiaoxue Hu Yiqiao Wang 《Journal of Combinatorial Optimization》2018,35(3):980-996
Let G be a connected graph with \(n\ge 2\) vertices. Suppose that a fire breaks out at a vertex v of G. A firefighter starts to protect vertices. At each step, the firefighter protects two vertices not yet on fire. At the end of each step, the fire spreads to all the unprotected vertices that have a neighbour on fire. Let sn\(_2(v)\) denote the maximum number of vertices in G that the firefighter can save when a fire breaks out at vertex v. The 2-surviving rate \(\rho _2(G)\) of G is defined to be the real number \(\frac{1}{n^2} \sum _{v\in V(G)} \mathrm{sn}_2(v)\). Then it is obvious that \(0<\rho _2(G)<1\). The graph G is called 2-good if there is a constant \(c>0\) such that \(\rho _2(G)>c\). In this paper, we prove that every planar graph with \(n\ge 2\) vertices and without chordal 5-cycles is 2-good. 相似文献
995.
The least squares fit in a linear regression is always unique even when the design matrix has rank deficiency. In this paper, we extend this classic result to linearly constrained generalized lasso. It is shown that under a mild condition, the fit can be represented as a projection onto a polytope and, hence, is unique no matter whether design matrix X has full column rank or not. Furthermore, a formula for the degrees of freedom is derived to characterize the effective number of parameters. It directly yields an unbiased estimate of degrees of freedom, which can be incorporated in an information criterion for model selection. 相似文献
996.
Zixing Tang Baoyindureng Wu Lin Hu Manoucheher Zaker 《Journal of Combinatorial Optimization》2017,33(2):580-589
A coloring of a graph \(G=(V,E)\) is a partition \(\{V_1, V_2, \ldots , V_k\}\) of V into independent sets or color classes. A vertex \(v\in V_i\) is a Grundy vertex if it is adjacent to at least one vertex in each color class \(V_j\) for every \(j<i\). A coloring is a Grundy coloring if every vertex is a Grundy vertex, and the Grundy number \(\Gamma (G)\) of a graph G is the maximum number of colors in a Grundy coloring. We provide two new upper bounds on Grundy number of a graph and a stronger version of the well-known Nordhaus-Gaddum theorem. In addition, we give a new characterization for a \(\{P_{4}, C_4\}\)-free graph by supporting a conjecture of Zaker, which says that \(\Gamma (G)\ge \delta (G)+1\) for any \(C_4\)-free graph G. 相似文献
997.
Since the seminal paper of Ghirardato (1997), it is known that Fubini theorem for non additive measures can be available only for functions as “slice-comonotonic” in the framework of product algebra. Later, inspired by Ghirardato (1997), Chateauneuf and Lefort (2008) obtained some Fubini theorems for non additive measures in the framework of product σ-algebra. In this article, we study Fubini theorem for non additive measures in the framework of g-expectation. We give some different assumptions that provide Fubini theorem in the framework of g-expectation. 相似文献
998.
文章结合物流资源配置过程的复杂性特征,提出考虑服务质量与服务柔性的汽车零部件物流资源组合优化配置策略,该策略设计了以汽车零部件全供应链信息共享平台为依托的跨组织物流资源优化配置流程,并重点对资源优化配置过程中的关键问题进行了描述,建立以时间、空间、成本、质量和效率为目标的汽车零部件物流资源组合优化配置模型,并给出基于改进的进化多目标优化算法的求解过程,最后以某企业汽车零部件物流资源组合配置的实例验证了该流程、优化配置模型及求解方法的有效性与实用性. 相似文献
999.
1000.
AbstractObjective: Existing literature on young adults’ e-cigarette and polysubstance use focused on college students. This study examined the differences between college and noncollege groups on prevalence and patterns of e-cigarette and other substance use using data from a national survey. Participants: Adults aged 18–24 from the 2013–2014 Population Assessment of Tobacco and Health Study (n?=?6,608). Methods: Independent sample t-tests and Chi-square tests were conducted to examine group differences. Results: Noncollege young adults had higher prevalence of cigarette, e-cigarette, and marijuana use; college students had higher prevalence of alcohol use. Among current e-cigarette users, college students had higher prevalence of polysubstance use of alcohol and marijuana. College students used e-cigarettes for socializing purposes more. Conclusions: Differences in prevalence and patterns of e-cigarette and other substance use between college and noncollege groups exist. Future interventions should target the social context of college life and reach out to noncollege young adults in workplaces. 相似文献