CHINA AND THE U.S. BEYOND THE KOREAN PENINSULA

China-U.S. cooperation over the most difficult security problem in Northeast Asia—the North Korean nuclear issue—in essence projects its bigger power game amid the tectonic shifts of Asian geopolitics. The nuclear issue affords a test case to gauge the future posture of China and the United States in East Asia and their partnership in that conflict-prone region. Approaches to resolving this issue must take into account the geopolitical realignment of Asia, Washington's reorientation of relations with its Asian allies, and China's rise as an influential regional player and the subsequent regional response. However, the long-standing mistrust between China and the United States is contributing to a lack of substantial progress in Korean nonproliferation efforts. The declared nuclear test by Pyongyang further put the denuclearization cooperation between China and the Unites States on the line. China-U.S. cooperation in denuclearizing Pyongyang may either produce lasting stability for the region or create ‘‘collateral damage,’’ with the North Korean issue paling in comparison.     

钢质油罐底板腐蚀概率估计

针对钢质油罐底板腐蚀,首先分析了油罐底板腐蚀工程检测数据的特点和腐蚀试验数据统计分析理论;然后针对工程检测信息不完全的特性,以最大腐蚀深度的预测估计为目标,建立了以轻微腐蚀面积估计来实现腐蚀概率修正估计的模型;最后利用广州等地27个罐约900条检测数据估计了油罐底板的最大腐蚀深度。其最大相对误差小于45%,约80%的相对误差优于30%。     

火炮模拟试验装置波形发生器参数试验设计

通过高速大质量块冲击炮口来推动火炮后坐是一种技术可行的火炮后坐模拟试验方法。为保证该模拟试验方法精度,基于ABAQUS软件建立了火炮模拟试验装置及力学模型;基于橡胶试样的拉伸、压缩试验得到橡胶材料的应力应变关系,建立了波形发生器的超弹性模型;选取波形发生器左右两个橡胶块的直径、硬度及厚度等结构参数为试验因素,根据火炮动态特性的平均及最大误差建立了目标函数,通过均匀设计试验获取了一组最优的结构参数,为火炮模拟试验装置的工程设计提供了依据。     

战斗机隐蔽接敌轨迹优化方法

针对空战对抗的隐蔽作战需求,对战斗机隐蔽接敌方法进行研究。基于战斗机雷达反射截面积的动态特性建立雷达探测威胁模型;以空战态势参数为状态建立接敌引导模型;以给定目标发现概率为暴露阈值进行威胁约束;以最小化接敌过程中累积被发现概率为性能指标;将战斗机隐蔽接敌问题建模为隐蔽性约束下的最优控制问题。为保证算法的实时性和有效性,引入滚动时域控制策略进行在线优化,并采用高斯伪谱法进行数值求解。仿真实验表明,通过路径约束和性能指标双重约束,能有效增强战斗机接敌的隐蔽性,算法实时性能满足战斗机控制的需求。     

基于CPU-GPU混合计算平台的RNA二级结构预测算法并行化研究

RNA二级结构预测是生物信息学领域重要的研究方向,基于最小自由能模型的Zuker算法是目前该领域最典型使用最广泛的算法之一。本文基于CPU GPU的混合计算平台实现了对Zuker算法的并行和加速。根据CPU和GPU计算性能的差异,通过合理的任务分配策略,实现二者之间的并行协作计算和处理单元间的负载平衡;针对CPU和GPU的不同硬件特性,对Zuker算法在CPU和GPU上的实现分别采取了不同的并行优化方法,提高了混合加速系统的计算性能。实验结果表明,CPU处理单元在混合系统中承担了14%以上的计算任务,与传统的多核CPU并行方案相比,采用混合并行加速方法可获得15.93的全局加速比;与最优的单纯GPU加速方案相比,可获得16%的性能提升,并且该混合计算方案可用于对其它生物信息学序列分析应用的并行和加速。     

Market entry strategy in the presence of market spillovers and efficiency differentiation

Firms form various alliances or use brand extensions to enter new markets in order to improve their operational efficiency and create a positive spillover. However, they do not always know the implications of these strategies for market entry and multimarket competition because the sale of products in one market can have negative spillover effects on product sales in other markets. We present an analytical framework to examine whether and how (i.e., by choosing alliance entry or independent entry) competing firms should enter a market in a situation where market spillovers occur when a firm enters a spillover-producing market to sell products that may increase or decrease the consumers' willingness to pay for products in the primary market. Our analysis shows that the operational efficiency (or quality differentiation ability) of firms in a spillover-producing market varies, and hence, the impact of market spillovers differs for firms. We identify the key factors, such as bargaining power, brand value difference in the primary market, and the extent of efficiencies and spillovers, that determine the firms benefitting from the different entry strategies. Specifically, we show that firms would be more willing to choose an alliance strategy to enter a spillover-producing market if the negative spillover is small and alliance efficiency is high. In contrast, if an alliance entry is not favored, the firms' relative operational efficiency is crucial for them to decide whether to enter the market independently under moderate spillover conditions. Finally, we show the implications of market entry strategies for managers.     

网络战对作战的影响及对策

网络战作为一种新的作战形式引入作战领域,越来越受到各国重视,并已成为世界各国争相研究和重点建设的作战样式。文章从网络战的特点入手,针对网络战对作战影响进行了探讨,并从构建网络体系、研发武器装备、重视人才培养和加强训练演练四个方面阐述了强化军队网络战的对策措施。     

空气甲醛显色球的制备

为实现快速准确测定空气中的甲醛,对4种氨基酸作为乙酰丙酮显色法的胺源进行对比分析,发现甘氨酸的显色效果较明显;对显色温度和显色时间进行优化,发现显色温度在50℃,反应15 min,显色效果明显。把显色剂固定到透明聚丙烯酸树脂球上,制备出可在家庭中方便使用的显色球,通过肉眼观察即可判断空气中甲醛的质量浓度,检测限达0.008 mg/m3。     

面向需求变化的军队自动化立体仓库货位优化

为提高军队自动化立体仓库的出库能力,提出应根据需求变化对在库物资货位进行动态调整,从而最大限度地保障军队物资需求。综合考虑堆垛机总行程、货物离散度和出库频率等评价指标,采用遗传算法对该多目标优化问题进行求解,并运用Matalab仿真。结果表明,该方法能较好地提高军队自动化立体仓库在需求动态变化时的出库能力。同时,该研究对一般仓库的货位优化也有一定的借鉴意义。     

逻辑靶场实现过程和关键技术分析

逻辑靶场基于公共的对象模型、软件平台和高速通信网络,集成了单个或多个靶场的各种资源,形成逻辑上的大型综合靶场,为联合试验训练提供了多靶场合成能力。提出了逻辑靶场规划、创建、测试和使用的总体技术过程,分析了逻辑靶场对象模型、逻辑靶场对象元模型、中间件、网关、规则和标准、支持工具等关键技术及实现方法,介绍了一种联合试验训练支撑平台,为实现逻辑靶场提供参考借鉴。