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671.
对修改消防法的思考 总被引:1,自引:0,他引:1
范平安 《中国人民武装警察部队学院学报》2004,20(4):29-30,33
随着改革开放的逐步深入发展 ,尤其是我国加入世贸组织后 ,消防工作面临许多新情况、新问题 ,修改《消防法》迫在眉睫。文章从六个方面论述了修改《消防法》的思路 ,以使《消防法》更加符合我国国情。 相似文献
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在阐述了电子对抗装备软件特点的基础上,对研制电子对抗装备软件过程中的测试策略与方法进行了初步的研究,并对在实施测试过程中的几个问题进行了探讨. 相似文献
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综合实践活动课程作为现代教育的重要内容,是国家新一轮课改的亮点和难点。调研发现,九年一贯制学校开设综合实践活动课程推动了学校重构教育教学层级与体系,能有效提升学生核心素养,促进教师职业成长与转型,帮助学校竖立校本特色与教育品牌影响力。九年一贯制学校开设综合实践活动是人才强国背景下的学生需求与文化适应的统一,是教师的使命和责任的体现,是传统教育与新型教育的融合与创新。 相似文献
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Changing and optimizing the projectile nose shape is an important way to achieve specific ballistic performance. One special ballistic performance is the embedding effect, which can achieve a delayed high-explosive reaction on the target surface. This embedding effect includes a rebound phase that is significantly different from the traditional penetration process. To better study embedment behavior, this study proposed a novel nose shape called an annular grooved projectile and defined its interaction process with the ductile metal plate as partial penetration. Specifically, we conducted a series of low-velocity-ballistic tests in which these steel projectiles were used to strike 16-mm-thick target plates made with 2024-O aluminum alloy. We observed the dynamic evolution characteristics of this aluminum alloy near the impact craters and analyzed these characteristics by corresponding cross-sectional views and numerical simulations. The results indicated that the penetration resistance had a brief decrease that was influenced by its groove structure, but then it increased significantly-that is, the fluctuation of penetration resistance was affected by the irregular nose shape. Moreover, we visualized the distribution of the material in the groove and its inflow process through the rheology lines in microscopic tests and the highlighted mesh lines in simulations. The combination of these phenomena revealed the embed-ment mechanism of the annular grooved projectile and optimized the design of the groove shape to achieve a more firm embedment performance. The embedment was achieved primarily by the target material filled in the groove structure. Therefore, preventing the shear failure that occurred on the filling material was key to achieving this embedding effect. 相似文献
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We study the problem of recovering a production plan after a disruption, where the disruption may be caused by incidents such as power failure, market change, machine breakdown, supply shortage, worker no‐show, and others. The new recovery plan we seek after has to not only suit the changed environment brought about by the disruption, but also be close to the initial plan so as not to cause too much customer unsatisfaction or inconvenience for current‐stage and downstream operations. For the general‐cost case, we propose a dynamic programming method for the problem. For the convex‐cost case, a general problem which involves both cost and demand disruptions can be solved by considering the cost disruption first and then the demand disruption. We find that a pure demand disruption is easy to handle; and for a pure cost disruption, we propose a greedy method which is provably efficient. Our computational studies also reveal insights that will be helpful to managing disruptions in production planning. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005. 相似文献
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在磁悬浮列车中,悬浮控制系统要求间隙传感器的动态特性,但无法用机械方法测试较高频率时的动态特性。根据传感器工作机制,用模拟涡流场来代替被测导体的涡流效应,提出基于调制/解调原理的动态特性测试方法,并分别对正弦信号和方波信号的测试方法进行了探讨。最后给出了两种特征信号的传感器动态特性测试结果。实验表明,这种方法能够满足测试要求,相对于机械方法有很大的优越性。 相似文献