舰载火箭炮火力系统对岸面目标的射击效力分析

构建了舰载火箭炮火力系统的射击效力模型,讨论了单发火箭弹和火力系统射击效力的有关问题,探讨了毁伤面积达到一定程度所需的火力系统的数量。计算结果表明,舰艇适宜加装舰载火箭炮火力系统,而不宜只加装多个独立的舰载火箭炮。     

某水下发射装置自由弯曲振动的流固耦合分析(英文)

A pneumatic launcher is theoretically investigated to study its natural transverse vibration in water. Considering the mass effect of the sealing cover, the launcher is simplified as a uniform cantilever beam with a top point mass. By introducing the boundary and continuity conditions into the motion equation, the natural frequency equation and the mode shape function are derived. An iterative calculation method for added mass is also presented using the velocity potential function to account for the mass effect of the fluid on the launcher. The first 2 order natural frequencies and mode shapes are discussed in external flow fields and both external and internal flow fields. The results show good agreement with both natural frequencies and mode shapes between the theoretical analysis and the FEM studies. Also, the added mass is found to decrease with the increase of the mode shape orders of the launcher.And because of the larger added mass in both the external and internal flow fields than that in only the external flow field, the corresponding natural frequencies of the former are relatively smaller.     

交变温度作用下推进剂耗散能与累计损伤的数值计算*

通过推进剂在交变温度作用下损耗能和累积损伤因子的数值计算,得到了不同载荷条件下推进剂的耗散能和累计损伤值,为固体火箭发动机加速老化过程与自然贮存相关性研究提供新的基础平台,为固体火箭发动机寿命预估新方法的探索提供参考。     

郊区自驾游旅游交通指引标志设置研究

当前旅游交通指引标志设置中存在缺乏区域系统考虑、设置分散、旅游信息过于集中等问题,导致自驾游出行者难以及时、准确、连续地获得指引信息。针对这一问题,从郊区自驾游出行者的需求出发,构建区域入口、区域内部、景区附近的旅游交通三级指引系统。重点探讨二级指引标志的设计原则与方法,提出在景区重要度分类和道路节点重要度分级的基础上,确定各景区指引范围和各道路节点指引容量,对旅游交通指引标志进行选址。最后以河北省平山县为例,对提出的旅游交通指引标志设置方法进行实证研究。     

基于GPS基线向量的舰载火箭弹姿态测量方法

提出一种利用GPS载波信号相位差测量技术进行实时确定弹体姿态的方法。通过对载波相位差测量航向和姿态原理的分析,建立GPS姿态确定的单差模型,推导采用GPS多天线姿态测量技术实时获取弹体飞行姿态的解算算法,应用最小二乘法估计解算基线向量,然后对GPS姿态估计算法进行仿真计算。仿真结果验证了模型、算法的正确性和有效性。     

我国游艇消费需求分析及游艇码头建设展望

借鉴国外游艇消费市场的特点,在对标美国游艇发展与经济发展相关性判断我国游艇市场发展前景的基础上,运用诱发量法、类比法,综合预测我国游艇消费需求量,并对我国沿海地区游艇码头建设进行了展望。     

火箭发动机水下分离特性试验研究

本文在大型压力水筒中研究了火箭发动机的水下分离特性.实验采用了锥型喷管,测量了火箭发动机在水下过膨胀条件下燃烧室压强和喷管扩张段不同截面处的压力.研究表明,与在空气中工作相比,火箭发动机在水下更容易产生气流分离.     

Implementation Challenges for Quota Set-Asides: Policy Analysis to Inform Fisheries Management Decision-Making

Abstract

The implementation of catch share programs can have socio-economic and ecological benefits, yet may also change the distribution of those benefits within a fishery or across communities. Quota set-asides can mitigate the impacts of these changes. During the implementation of the West Coast groundfish trawl catch share program, 10% of the quota was set aside to be used toward five goals in the Adaptive Management Program (AMP). This quota was to serve as an insurance policy during the substantial changes that were expected to occur under the new management regime. However, this program has not yet been fully developed, in part due to delayed decision-making and the controversial nature of allocating quota. Here, we examine and score six policy options for the AMP against four criteria: effectiveness, flexibility, political viability, and implementability. While each of the options has strengths and weaknesses, those that ranked highly include allocating quota pounds (QP) via the status quo and via auction. Our results highlight the drawbacks of delaying contentious decisions, where uncertainty for participants can constrain operational decisions and subsequent economic gains. We demonstrate the utility of this decision-making framework for evaluating tradeoffs between alternatives, especially for a program with multiple, competing objectives.     

舰空导弹发射装置维修性参数选择和指标确定

完善的参数指标体系对于维修性评估验证具有重要意义。针对舰载防空导弹发射装置的使用环境和结构特点,在分析维修性定性要求的基础上,依据确立的参数选择原则,进行了维修性定量参数的选择,并对定量指标的确定进行了分析。分析总结了维修性指标评估验证方法。     

海洋环境温度下固体火箭发动机的温度和应力分析

为了预估海洋环境温度对舰载导弹固体火箭发动机的累积损伤作用,保证发动机的正常工作,以2个海区为环境对象,通过环境温度模型、传热模型和粘弹性本构关系,用有限元法求解了舰载导弹固体火箭发动机对海洋环境的温度和应力响应,得到了发动机中的温度分布和应力分布.结果表明,同样粘结强度时,发动机第一粘结界面比第二粘结界面更容易脱粘;药柱中星尖处应力最大,是产生裂纹的危险部位;冬季是发动机药柱容易产生裂纹的危险季节.