具有阻力特性材料的σ_f－σ关系及一种新的阻力曲线测定方法

通过对相变增韧陶瓷及一种可切削玻璃－陶瓷动态疲劳（恒应力速率）试验中高应力速率区断裂应力下降现象的理论分析，发现这种现象与材料的阻力特性（Ｒ－ｃｕｒｖｅ）密切相关。确立的σ_ｆ－σ理论关系能够很好地描述整个应力速率区间内的动态疲劳试验结果。高应力速率区σ_ｆ－σ在双对数坐标下为负斜率直线，直线斜率为（ｍ为阻力曲线ＫＲ＝ｋ（△ａ）~ｍ的指数），断裂主要由材料阻力行为控制；低应力速率区，σ_ｆ－σ在双对数坐标下为正斜率直线，直线斜率为　（ｎ为应力腐蚀指数），断裂主要由材料应力腐蚀行为控制。建立了测定材料阻力特性的一种新方法，分别用这种方法及压痕／弯曲方法对一种可切削玻璃－陶瓷的阻力特性进行了实验测定，两种方法所得结果有很好的一致性。     

春光油田现代油藏经营管理模式的

介绍并分析了春光油田现代油藏经营管理模式的构建与运作及实施效果.     

加气混凝土切割机的特性与选用

文章分析了我国目前生产加气混凝土制品的各种切割工艺及采用的切割设备--地翻型切割机、空中翻转型切割机、长杆式切割机、预铺式切割机、压入式切割机、栅条式切割机(JQS)钢带式切割机的工艺特点.介绍了选用这些切割机应注意的问题,指出必须结合实际的生产工艺、产品要求及场地特点、投资大小合理选择切割机.     

Novel algorithms for shared segment protection

The major challenges in designing survivable schemes are how to allocate a minimal amount of spare resources (e.g., bandwidth) using fast (e.g., polynomial-time) algorithms, and, in case a failure occurs, to be able to recover quickly from it. All existing approaches invariably make tradeoffs. We propose novel shared segment protection algorithms which make little or no compromise . We develop an elegant integer linear programming (ILP) model to determine an optimal set of segments to protect a given active path. Although the ILP approach is useful for a medium-size network, it is too time consuming for large networks. Accordingly, we also design a fast heuristic algorithm based on dynamic programming to obtain a near-optimal set of segments. Although the heuristic algorithm has a polynomial time complexity, it can achieve a bandwidth efficiency as high as some best-performing shared path protection schemes and, at the same time, much faster recovery than these shared path protection schemes. The proposed scheme is also applicable to a wide range of networking technologies, including Internet Protocol and wavelength-division multiplexing networks under the generalized multiprotocol label switched framework.     

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本文通过对在用钻机井架的现场实际测试,建立数据库、测评模型,对实测的数据用计算机技术进行分析,提出了初始弯曲应力;数据正态分布检验——x～2检验;建立回归方程;在给定置信度下测评当前承载能力的技术概念。解决了在用钻机A型井架的安全性评估问题,是一种较为合理、可靠、科学的测评技术和方法。     

NexGen的Nx586－Pentium的又一个挑战者

本文简单介绍ＮｅｘＧｅｎ公司最新设计出的Ｎｘ５８６ＣＰＵ。它是一种８０×８６兼容的处理器，文中介绍了它的微体系结构，ＲＩＳＣ８６指令等。     

Spatial memory deficits following stimulation of hippocampal 5-HT1B receptors in the rat

The authors review the principles of reconstructive surgery for lower limb salvage after severe lower limb trauma to determine factors that have been used as decision-making criteria for limb salvage or amputation in severe lower extremity injuries and the methods of reconstruction and their outcome. The use of scoring systems and their value in acute decision making (primary amputation or limb salvage) are described. Soft-tissue reconstructive techniques, with emphasis on the use of flaps and the importance of selecting the best technique and time for the reconstruction are reviewed. Skeletal reconstructive techniques are described, including available options and currently held views on indications and use of the best contemporary methods. It is essential for the physician to make a good initial decision on the need for primary amputation or limb salvage. A multidisciplinary approach is fundamental to successful salvage.     

国外特种反坦克武器的发展动向

本文着重将目前国外比较活跃的几种新型反垣克武器；软杀伤反坦克弹药，末敏弹，反坦克地雷以及智能反坦克子弹药的基本原理，作战效能，装备情况作一介绍，并对其发展方向进行了预测。     

Application of model predictive control strategy based on fuzzy identification to an SP-100 space reactor

In this work, a model predictive control method combined with fuzzy identification, is applied to the design of the thermoelectric (TE) power control in the SP-100 space reactor. The future TE power is predicted by using the fuzzy model identified by a subtractive clustering method of a fast and robust algorithm. The objectives of the proposed fuzzy model predictive controller are to minimize both the difference between the predicted TE power and the desired power, and the variation of control drum angle that adjusts the control reactivity. Also, the objectives are subject to maximum and minimum control drum angle and maximum drum angle variation speed. The genetic algorithm that is effective in accomplishing multiple objectives is used to optimize the fuzzy model predictive controller. A lumped parameter simulation model of the SP-100 nuclear space reactor is used to verify the proposed controller. The results of numerical simulations to check the performance of the proposed controller show that the TE generator power level controlled by the proposed controller could track the target power level effectively, satisfying all control constraints.