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111.
兵团精神是社会主义核心价值体系在兵团的具体体现,是兵团文化的核心与精髓,是指引兵团人实现兵团跨越式发展和长治久安的精神动力和智力支持。开展兵团精神教育是屯垦戍边和"教育戍边"事业进程中的一个重要课题。本文在教育价值论的视角下分析开展兵团精神教育所依托的优势资源,包括文化资源优势、特殊体制优势、理论指导优势及实践经验优势等,并在此基础上分别从本质属性、理论创新及学生发展三个方面进一步探讨了兵团精神的教育价值。 相似文献
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以弹性基上圆柱管为研究对象,基于高阶剪切变形梁理论推导了Winkler弹性基圆柱管弯曲变形的高阶剪切梁理论控制方程,给出四种典型工况弯曲问题的精确解.研究表明,无须假设剪切修正系数,只需引入适当横截面翘曲形状函数,高阶梁理论在圆柱管内外表面满足剪应力τxr为零的边界条件,且对于不同长径比和厚径比的圆柱管弯曲问题均能提供... 相似文献
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A variational inhomogeneous image segmentation model based on fuzzy membership functions and Retinex theory is proposed by introducing the fuzzy membership function.The existence of the solution of the proposed model is proved theoretically.A valid algorithm is designed to make numerical solution of the model under the framework of alternating minimization.The last experimental results show that the model can make segmentation of the real image with intensity inhomogeneity effectively. 相似文献
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In this study, the buckling analysis of a Graphene oxide powder reinforced (GOPR) nanocomposite shell is investigated. The effective material properties of the nanocomposite are estimated through Halpin-Tsai micromechanical scheme. Three distribution types of GOPs are considered, namely uniform, X and O. Also, a first-order shear deformation shell theory is incorporated with the principle of virtual work to derive the governing differential equations of the problem. The governing equations are solved via Galerkin's method, which is a powerful analytical method for static and dynamic problems. Comparison study is performed to verify the present formulation with those of previous data. New results for the buckling load of GOPR nanocomposite shells are presented regarding for different values of circumfer-ential wave number. Besides, the influences of weight fraction of nanofillers, length and radius to thickness ratios and elastic foundation on the critical buckling loads of GOP-reinforced nanocomposite shells are explored. 相似文献
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Higher-order shear and normal deformation theory is used in this paper to account thickness stretching effect for free vibration analysis of the cylindrical micro/nano shell subjected to an applied voltage and uniform temperature rising. Size dependency is included in governing equations based on the modified couple stress theory. Hamilton's principle is used to derive governing equations of the cylindrical micro/nano shell. Solution procedure is developed using Navier technique for simply-supported boundary conditions. The numerical results are presented to investigate the effect of significant parameters such as some dimensionless geometric parameters, material properties, applied voltages and temperature rising on the free vibration responses. 相似文献
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排队论在导弹防御体系射击效能中的应用 总被引:6,自引:0,他引:6
针对当前空袭手段多样化、综合化和一体化的特点,运用排队论方法,设计了一种基于排队论的射击效能评估模型。该模型综合考虑了各种因素对舰空导弹射击效能的影响,当编队的配置(如防御层数、通道数量)有所变化时,依然可以灵活运用上述模型对编队射击效能做出准确评估。 相似文献
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Marco Slikker 《海军后勤学研究》2006,53(4):235-242
We study sequencing situations with a fixed initial order and linear cost functions. Cost savings can be obtained by rearranging jobs. Next to finding an optimal order, an additional issue is formed by the division of these savings. Cooperative game theory studies this issue. A common assumption states that cooperation between players is restricted to groups that are connected according to the initial order. The value of disconnected groups is defined additively over their connected components. In this paper we allow players in disconnected coalitions to switch places as long as they do not hurt the players not in the coalition under consideration. The resulting games are called relaxed sequencing games. Although they have been studied before, no general results on stable profit divisions have been derived so far. In this paper we prove that relaxed sequencing games have a nonempty core, i.e., they all have stable profit divisions. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006 相似文献