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681.
油罐的壁厚设计关系到油罐的经济性和可靠性,如何把握两者的辩证关系对油罐的设计与建设具有十分重要的意义。传统上大型油罐壁厚设计采用的是变点法;以可靠度理论为基础,以可靠性分析模型为核心,提出利用可靠度法求解大型油罐壁厚的新方法。以50 000 m3油罐为例,编程分析并计算以2种方法设计的壁厚。变点法设计的底圈罐壁厚度与圈数无关;以中心点可靠度法求解壁厚,可靠性指标一定时,底圈罐壁厚度同样与圈数无关。探讨可靠度法求解壁厚的可行性,验证变点法设计壁厚的可靠性。 相似文献
682.
本文研究建立应急机动部队战时军械勤务指挥自动化系统,文中对系统设计的目标、指导思想及系统的硬件配置和应用软件功能进行了论述。 相似文献
683.
舰载红外警戒系统多目标跟踪算法研究 总被引：6，自引：1，他引：6
多目标跟踪有着十分广泛的应用,目前国内外多目标跟踪的研究重点都集中在雷达等主动传感器上,但是对于红外的多目标跟踪领域却研究较少。对于红外系统,目标跟踪的最大特点是观测量只有角度,没有距离,这就使得传统的跟踪滤波问题遇到困难。通过讨论舰载红外警戒系统的多目标跟踪算法,分析目标与传感器的特点,提出了一整套多目标跟踪的算法。仿真结果表明,此套算法能满足工程应用的要求。 相似文献
684.
本文根据我国弹药产品的特点,提出了弹药贮存可靠性指标的确定程序、贮存可靠性指标的内容及其对应的贮存条件。从原材料的选择、元器件的控制、结构设计、包装设计,生产工艺、组装时间,贮存管理等方面,论述了贮存可靠性的保证措施,并提出了三种贮存可靠性预计方法。 相似文献
685.
本文针对现阶段弹药贮存可靠性数据不充分和研制阶段贮存可靠性评定比较困难的现状,提出了弹药可靠贮存寿命的4种预计方法,对每种方法的适用场合、实施步骤,特别是对相似产品法在弹药可靠贮存寿命中的应用做了较为详细的介绍。 相似文献
686.
TCP/IP协议簇是一个实际上的网际协议标准,4BSD UNIX操作系统提供了网际间通信的socket机制,以解决应用程序与TCP/IP软件的接口,客户-服务器模型已成为网际环境下的程序设计的实际标准模式。较详细分析了客户-服务器模型的原理,socket编程机制的系统调用,并给出了基于socket系统调用的客户服务器模型实现的方法。 相似文献
687.
Dongwei Li;Joshua Ignatius;Dujuan Wang;Yunqiang Yin;T.C.E. Cheng; 《海军后勤学研究》2024,71(2):241-285
Increasing environmental concerns and e-commerce has attracted a growing focus on reverse logistics that not only delivers some goods to customers but also picks up other goods from customers. To achieve cost-efficient and fast deliveries, integrating drones into the delivery and pickup services provides a competitive advantage, which however increases the operational challenges. We consider a truck-drone routing problem with simultaneous delivery and pickup, where each truck carries a set of heterogeneous drones. Each truck can simultaneously perform its own delivery and pickup, and serve as an intermediate movable depot from which multiple drones can be dispatched to serve customers when the truck arrives at a customer, and the truck must wait until all the drones return. The energy consumption of drones is considered during their flights. All the delivery services must be performed, whereas the pickup services are optional with certain rewards. The objective is to find the synthetic-routes of the truck-drone combinations so as to minimize the sum of the assignment cost and the transport cost of the trucks and drones minus the total pickup revenue. To solve the problem, we devise a tailored branch-and-price-and-cut algorithm incorporating a specialized two-stage bidirectional labeling algorithm to solve the challenging pricing problem. To enhance the efficiency of the algorithm, we use the subset-row inequalities to tighten the lower bound, and apply some heuristic pricing strategies to quickly solve the pricing problem. We perform extensive numerical studies to assess the performance of the developed algorithm, analyze the merit of the truck-drone cooperative service mode over the truck-only service mode and the superiority of the configuration with heterogeneous drones, and ascertain the impacts of the key model parameters to generate managerial insights. We also show how our model would perform should it be used for the medical supply delivery and pickup in Shenzhen, China. 相似文献
688.
Xianpei Hong;Ying-Ju Chen;Yeming Gong;Hua Wang; 《海军后勤学研究》2024,71(2):286-317
While the previous literature on green technology adoption has not fully considered information sharing, we consider the impact of demand information sharing on the adoption of green technologies by risk-averse farmers in a vertical agricultural supply chain. We find that government subsidies and information sharing do not always promote farmers' adoption of green technologies. The accuracy of the information plays a vital role in promoting farmers' adoption of green technologies; however, the increased green technology adoption induced by more accurate information may be detrimental to farmer welfare in the presence of production diseconomies. Information sharing can reduce the amount of government subsidies for promoting green technology adoption, thereby suggesting the substitutable role of information and monetary instruments. Nonetheless, information-sharing may lead to lower water savings and thus should be adopted with caution. Risk aversion has a nontrivial impact on agricultural technology adoption: farmers are more likely to adopt traditional agricultural technologies when their risk aversion is either very low or very high. Finally, we validate our decision model with U.S. Department of Agriculture cotton production data and propose management insights to help farmers make appropriate adoption decisions under information asymmetry and risk-averse attitudes. 相似文献
689.
Mengnan Wang;Juliang Zhang;T. C. E. Cheng; 《海军后勤学研究》2024,71(5):645-659
To encourage consumers to reuse their used products, some manufacturers launch second-hand platforms while others adopt sharing platforms. Which platform benefits them more is an interesting problem for such manufacturers. To address this problem, we propose a two-period model in which heterogeneous consumers decide whether to buy new products in Period 1 or to rent (buy) used products on the platform in Period 2. Under a proportional transaction fee, we show that the two platforms can benefit the manufacturer if the unit production cost is high, and the valuation difference is low or the number of high-value consumers in Period 1 is fewer than in Period 2. Moreover, the two platforms are equivalent when the salvage value is 0. When the salvage value is positive, the second-hand platform benefits the manufacturer more than the sharing platform. The sharing platform induces the manufacturer to set a higher sale price than the second-hand platform when the unit production cost is high and there are fewer high-value consumers in Period 1. Otherwise, the sale and reselling prices are higher under the second-hand platform. We also consider the cases with a general consumer valuation distribution, multiple product life cycles, and a fixed transaction fee. Our findings can help manufacturers make the decision on platform choice to handle used products. 相似文献
690.
Motivated by challenges in the smartphone manufacturing industry, we develop a dynamic production ramp-up model that can be applied to economically satisfy nonstationary demand for short-life-cycle products by high-tech companies. Due to shorter life cycles and more rapid evolution of smartphones, production ramp-up has been increasingly critical to the success of a new smartphone. In the production ramp-up, the key challenge is to match the increasing capacity to nonstationary demand. The high-tech smartphone manufacturers are urged to jointly consider the effect of increasing capacity and decreasing demand. We study the production planning problem using a high-dimensional Markov decision process (MDP) model to characterize the production ramp-up. To address the curse of dimensionality, we refine Monte Carlo tree search (MCTS) algorithm and theoretically analyze its convergence and computational complexity. In a real case study, we find that the MDP model achieves revenue improvement by stopping producing the existing product earlier than the benchmark policy. In synthetic instances, we validate that the proposed MCTS algorithm saves computation time without loss of solution quality compared with traditional value iteration algorithm. As part of the Lenovo production solution, our MDP model enables high-tech smartphone manufacturers to better plan the production ramp-up. 相似文献