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31.
当前我国基础教育领域正在进行一场意义深远的课程改革,促进信息技术与课程整合成为其中的重要内容之一。信息技术与中小学数学学科的整合,使得中小学数学教学中学习内容和学习形式、教学观念和教学方式都产生了一系列的变化,本文通过在初中数学教学中进行的信息技术与课程整合实践尝试,总结了将信息技术有效地与中学数学课程整合,可以培养学生学习数学兴趣和实践能力。 相似文献
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AbstractThe Military Compensation and Retirement Modernization Commission was established by the Congress in 2013 to perform a systematic review of military compensation to address rising costs and other trends. Their recommendation for reforming the TRICARE health care program was sweeping, and differed greatly from earlier proposals that focused on increasing beneficiary cost shares. Specifically, the commission proposed overhauling the current benefit delivery model and replacing it with a premium-based insurance model offering a menu of DoD-sponsored private health plans. The analysis presented here is based on work that supported the commission by estimating the budgetary impact of its proposed reforms. Results indicate that movement towards the premium-based model would produce an annual budgetary cost savings in the $2 billion to $4 billion range, with a best savings estimate of $3.2 billion. 相似文献
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We consider scheduling a set of jobs with deadlines to minimize the total weighted late work on a single machine, where the late work of a job is the amount of processing of the job that is scheduled after its due date and before its deadline. This is the first study on scheduling with the late work criterion under the deadline restriction. In this paper, we show that (i) the problem is unary NP‐hard even if all the jobs have a unit weight, (ii) the problem is binary NP‐hard and admits a pseudo‐polynomial‐time algorithm and a fully polynomial‐time approximation scheme if all the jobs have a common due date, and (iii) some special cases of the problem are polynomially solvable. 相似文献
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Lawrence E. Cline 《Defense & Security Analysis》2016,32(4):293-311
Particularly in African operations, United Nations (UN) peacekeeping forces have faced significant problems in restoring stability. In at least a few situations, unilateral national military interventions have been launched in the same countries. In the cases of Sierra Leone and Côte d’Ivoire, the British and French interventions respectively played a significant role in re-establishing stability. Lessons from these operations suggest that if effective coordination and liaison channels are established, such hybrid unilateral-UN missions can in fact be more successful than “pure” peace operations. 相似文献
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We consider a single-machine scheduling model in which the job processing times are controllable variables with linear costs. The objective is to minimize the sum of the cost incurred in compressing job processing times and the cost associated with the number of late jobs. The problem is shown to be NP-hard even when the due dates of all jobs are identical. We present a dynamic programming solution algorithm and a fully polynomial approximation scheme for the problem. Several efficient heuristics are proposed for solving the problem. Computational experiments demonstrate that the heuristics are capable of producing near-optimal solutions quickly. © 1998 John Wiley & Sons, Inc. Naval Research Logistics 45: 67–82, 1998 相似文献
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Robert E. Bechhofer 《海军后勤学研究》1985,32(4):665-674
This article describes a new closed adaptive sequential procedure proposed by Bechhofer and Kulkarni for selecting the Bernoulli population which has the largest success probability. It can be used effectively for selecting the production process with the largest proportion of conforming items, and thus is applicable in vendor selection situations. The performance of this procedure is compared to that of the Sobel-Huyett single-stage procedure, and to a curtailed version of the single-stage procedure, all of which guarantee the same probability of a correct selection. Optimal properties of the Bechhofer-Kulkarni procedure are stated; quantitative assessments of important performance characteristics of the procedure are given. These demonstrate conclusively the superiority of the new procedure over that of the competing procedures. Relevant areas of application (including clinical trials) are described. Appropriate literature references are provided. 相似文献
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The use of life-cycle costs in procurement is limited by the accuracy of cost estimates and assessments of availability risks under the conditions generating costs. Critical to these problems are the needs and responses of equipment to maintenance and repair. Using transition probabilities to define the relationships between serviceability and maintenance and repairs, this article develops a comprehensive decision support system for military procurement. It uses a dynamic programming model to determine the least-cost set of maintenance and repair decisions, where adjustments are included for warranty conditions, time value of money, the opportunity costs of equipment failure, and the end-of-cycle salvage values or disposal costs. The system allows users to define working and failed states, create their own rules or indicators of availability from estimates of state probabilities and establish thresholds of risk acceptability. 相似文献
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