甲基二氯硅烷甲醇醇解产物含量的红外与核磁共振分析

本文对二甲苯溶剂中ＭｅＳｉＨＣｌ２ 和甲醇的反应产物Ｍｅ （ＯＭｅ）２ＳｉＨ 及ＭｅＳｉ（ＯＭｅ）３ 作了红外和核磁共振分析， 结果表明： 以红外谱图中Ｓｉ－Ｈ 和苯环吸收带作为含量分析谱带， 采用比例法， 借助工作曲线，可确定反应产物的含量。亦可以通过对各组分处于不同化学位移下质子的核磁共振分析，采用归一化法，经过换算测定反应产物混合液中各组份含量。两种测定方法均简便快捷， 并对两法的测定结果作了分析比较。     

我国城乡消防安全治理保障机制研究——以京津冀区域城乡一体化为视角

城乡消防安全的治理是我国公共安全管理的棘手问题之一。立足京津冀区域城乡一体化视角,解析京津冀城乡消防安全治理面临的诸多挑战,进而提出通过法治、财政、基础设施、安全力量、消防服务社会化五维度构建治理保障机制的设想,希冀为我国城乡消防安全治理理论与实务的研究抛砖引玉,从而进一步促进区域乃至全社会安全稳定。     

涂层厚度与耐蚀性能的研究

用电化学方法（包括交流阻抗法和线性极化法）测定了不同厚度涂层的耐蚀性能,并从定量的角度研究厚度对其耐蚀性能的影响．实验结果证实这一设想是可行的．     

装备修理任务最优分配模型

装备修理是我军一项计划性强、涉及面广和费用颇高的系统工作。本文首先系统分析了装备修理的组织过程。在此基础上,建立了适用于总部、军区等上下各级装备修理任务分配的数学规划模型,并对模型进行了讨论,同时对模型中目标函数的获取提供了一条可行的技术途径。最后,举例说明了该模型的应用。     

基于DoDAF与Petri网的预警卫星系统建模分析

预警卫星系统在弹道导弹防御系统中处在最前沿,在战争中起着其他装备无法替代的作用。依据DoDAF和预警卫星系统的作战流程,构建了预警卫星系统作战状态转换(OV-6b)模型,以描述预警卫星系统作战过程的时序关系、各作战节点的状态转换以及信息流关系。基于Petri网将各节点OV-6b模型转换成可执行模型进行驱动,并构建和分析了各Petri网模型的可达图,结果表明,建立的OV-6b模型和Petri网模型是合理的、正确的。     

航天部队综合试验能力的评估模型及系统实现

从航天部队的试验任务实际情况出发,研究了航天部队的综合试验能力评估要素,从评估节点、标准、分值、方法等方面着手,建立了功能完备的评估模型。以该评估模型为依据,开发了部队综合试验能力评估系统软件并进行了系统仿真。     

夺取心理优势的谋略运用

心理战是信息化条件下一种重要的作战样式,围绕双方心理优势的"角逐"将贯穿整个作战始终。"实则虚之,引敌上钩"、"虚则实之,慑敌妄动"、"虚则虚之,惑敌为实"、"实则实之,引敌为虚"、"虚实结合,迷敌心智"等谋略运用将是夺取"心理优势"的重要途径。     

Newsvendor problems with sequentially revealed demand information

This article analyzes a capacity/inventory planning problem with a one‐time uncertain demand. There is a long procurement leadtime, but as some partial demand information is revealed, the firm is allowed to cancel some of the original capacity reservation at a certain fee or sell off some inventory at a lower price. The problem can be viewed as a generalization of the classic newsvendor problem and can be found in many applications. One key observation of the analysis is that the dynamic programming formulation of the problem is closely related to a recursion that arises in the study of a far more complex system, a series inventory system with stochastic demand over an infinite horizon. Using this equivalence, we characterize the optimal policy and assess the value of the additional demand information. We also extend the analysis to a richer model of information. Here, demand is driven by an underlying Markov process, representing economic conditions, weather, market competition, and other environmental factors. Interestingly, under this more general model, the connection to the series inventory system is different. © 2012 Wiley Periodicals, Inc. Naval Research Logistics 2012     

Peridynamic modeling and simulation of thermo-mechanical de-icing process with modified ice failure criterion

De-icing technology has become an increasingly important subject in numerous applications in recent years. However, the direct numerical modeling and simulation the physical process of thermo-mechanical deicing is limited. This work is focusing on developing a numerical model and tool to direct simulate the de-icing process in the framework of the coupled thermo-mechanical peridynamics theory. Here, we adopted the fully coupled thermo-mechanical bond-based peridynamics (TM-BB-PD) method for modeling and simulation of de-icing. Within the framework of TM-BB-PD, the ice consti-tutive model is established by considering the influence of the temperature difference between two material points, and a modified failure criteria is proposed, which takes into account temperature effect to predict the damage of quasi-brittle ice material. Moreover, thermal boundary condition is used to simulate the thermal load in the de-icing process. By comparing with the experimental results and the previous reportedfinite element modeling, our numerical model shows good agreement with the pre-vious predictions. Based on the numerical results, we find that the developed method can not only predict crack initiation and propagation in the ice, but also predict the temperature distribution and heat conduction during the de-icing process. Furthermore, the influence of the temperature for the ice crack growth pattern is discussed accordingly. In conclusion, the coupled thermal-mechanical peridynamics formulation with modified failure criterion is capable of providing a modeling tool for engineering ap-plications of de-icing technology.     

Partial penetration of annular grooved projectiles impacting ductile metal targets

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.