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许多国家和国际性科学组织在科研诚信建设方面都开展了大量工作。目前,国内对于国外这方面的做法和经验,特别是近年来的最新实践只有零星的报道。文章比较全面地介绍国外科研诚信建设的主要发展动向和各国面临的一些共同挑战,进而分析提出其对我国科研诚信建设策略的启示,并就今后应加强的若干方面工作提出建议。 相似文献
363.
Jon Strandquist 《Small Wars & Insurgencies》2017,28(2):337-360
Foreign policy program transfer, the shifting of implementation responsibility for a foreign policy program from one organization to another, is a ubiquitous, yet under-studied, counterinsurgency phenomenon. This article conceptually develops program transfer as an important object of study; analyzes, using archival sources, an empirical case of program transfer, Operation Switchback, drawn from US counterinsurgency practice in South Vietnam; and formulates two preliminary theoretical claims related to program transfer: (1) transferred programs will tend to be altered in accordance with the characteristics of the gaining organization, and (2) program transfer may act as a signal or early-warning indicator of foreign policy change. 相似文献
364.
为减小抗干扰接收机硬件实现难度,深入研究单天线卫星导航抗干扰相关接收机的性能,并详细分析其频域响应、信干噪比损耗和相关输出函数。分析表明,抗干扰最优接收机与相关接收机信干噪比损耗随着干扰带宽和干扰强度的增加而增大,随干扰频率与中心频率偏差和噪声带宽的增加而减小。此外,干扰将引起抗干扰接收机匹配与相关输出主峰降低和旁瓣抬高,从而影响接收机捕获、跟踪和多径抑制性能。研究结果将为卫星导航抗干扰接收机的优化设计提供依据。 相似文献
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We consider a two‐level system in which a warehouse manages the inventories of multiple retailers. Each retailer employs an order‐up‐to level inventory policy over T periods and faces an external demand which is dynamic and known. A retailer's inventory should be raised to its maximum limit when replenished. The problem is to jointly decide on replenishment times and quantities of warehouse and retailers so as to minimize the total costs in the system. Unlike the case in the single level lot‐sizing problem, we cannot assume that the initial inventory will be zero without loss of generality. We propose a strong mixed integer program formulation for the problem with zero and nonzero initial inventories at the warehouse. The strong formulation for the zero initial inventory case has only T binary variables and represents the convex hull of the feasible region of the problem when there is only one retailer. Computational results with a state‐of‐the art solver reveal that our formulations are very effective in solving large‐size instances to optimality. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010 相似文献
368.
Accelerated life testing (ALT) is widely used to determine the failure time distribution of a product and the associated life‐stress relationship in order to predict the product's reliability under normal operating conditions. Many types of stress loadings such as constant‐stress, step‐stress and cyclic‐stress can be utilized when conducting ALT. Extensive research has been conducted on the analysis of ALT data obtained under a specified stress loading. However, the equivalency of ALT experiments involving different stress loadings has not been investigated. In this article, a log‐location‐scale distribution under Type I censoring is considered in planning ALT. An idea is provided for the equivalency of various ALT plans involving different stress loadings. Based on this idea, general equivalent ALT plans and some special types of equivalent ALT plans are explored. For demonstration, a constant‐stress ALT and a ramp‐stress ALT for miniature lamps are presented and their equivalency is investigated. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010 相似文献
369.
延永生 《兵团教育学院学报》2009,19(3):69-71
本文对“形势与政策”课的基本任务、基本特点进行了分析,并就如何加强“形势与政策”课程建设问题进行了探讨。 相似文献
370.
从概率论和信息论两个角度对单一基窃听方式下B92协议的安全性进行了研究,得出了最佳窃听角度和信源概率分布之间的关系;以马尔柯夫串联信道模型计算了Alice和Eve之间及Alice和Bob之间的信息量,并与广义量子测量窃听进行了比较,结果表明,Eve采用单一基窃听不仅能以较高概率猜中Alice发出的量子态,并且能获得较高平均互信息.得出的结论为合法通信者的安全通信和对窃听者的检测提供了标准. 相似文献