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301.
刘青志 《海军工程大学学报》2000,(6):91-93
介绍了VB在多媒体编程上的优势;说明了用VB实现控制系统原理模拟的各种多媒体方法:信号流、声响效果的实现和控制;各种仪表、信号波形的动画显示;各元件及系统数学模型的建立;控制原理的实现过程等,并给出了实现的一般框图. 相似文献
302.
《防务技术》2022,18(9):1513-1522
It is important to understand how ballistic materials respond to impact from projectiles such that informed decisions can be made in the design process of protective armour systems. Ballistic testing is a standards-based process where materials are tested to determine whether they meet protection, safety and performance criteria. For the V50 ballistic test, projectiles are fired at different velocities to determine a key design parameter known as the ballistic limit velocity (BLV), the velocity above which projectiles perforate the target. These tests, however, are destructive by nature and as such there can be considerable associated costs, especially when studying complex armour materials and systems. This study proposes a unique solution to the problem using a recent class of machine learning system known as the Generative Adversarial Network (GAN). The GAN can be used to generate new ballistic samples as opposed to performing additional destructive experiments. A GAN network architecture is tested and trained on three different ballistic data sets, and their performance is compared. The trained networks were able to successfully produce ballistic curves with an overall RMSE of between 10 and 20 % and predicted the V50 BLV in each case with an error of less than 5 %. The results demonstrate that it is possible to train generative networks on a limited number of ballistic samples and use the trained network to generate many new samples representative of the data that it was trained on. The paper spotlights the benefits that generative networks can bring to ballistic applications and provides an alternative to expensive testing during the early stages of the design process. 相似文献
303.
动态项重写计算(DTRC)是项重写系统(TRS)的元计算模型,具有层次化结构和动态重写等特征,可应用于归纳定理的形式自动证明以及项重写系统弱终止性的形式自动证明等方面.文中介绍了一个基于DTRC的形式自动证明平台及其在TRS弱终止性自动证明上的应用. 相似文献
304.
对武器装备供应管理系统结构和功能进行了分析,给出系统的一般构成模式和运行要求,阐明了其所需的决策支持;以系统一般模式为背景,探讨了利用多Agent系统理论构建装备供应管理支持系统的思路,提出支持系统的组成框架,并说明了其主要特点;最后,对支持系统的信息监控过程做了具体研究,给出了相应程序。 相似文献
305.
We consider a setting in which inventory plays both promotional and service roles; that is, higher inventories not only improve service levels but also stimulate demand by serving as a promotional tool (e.g., as the result of advertising effect by the enhanced product visibility). Specifically, we study the periodic‐review inventory systems in which the demand in each period is uncertain but increases with the inventory level. We investigate the multiperiod model with normal and expediting orders in each period, that is, any shortage will be met through emergency replenishment. Such a model takes the lost sales model as a special case. For the cases without and with fixed order costs, the optimal inventory replenishment policy is shown to be of the base‐stock type and of the (s,S) type, respectively. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012 相似文献
306.
提出了一种基于四阶累积量的双基地MIMO雷达收发角度估计算法。在接收端,通过分别构造单阵元和双阵元的四阶累积量矩阵,采用基于四阶累积量的MUSIC算法和ESPRIT算法分别估计出目标的离开方向(DOD)和波达方向(DOA),并且DOD和DOA自动配对。该算法将二维参数的估计问题转化为两个一维形式,不需要二维谱峰搜索,在保证二维方位角估计性能的基础上,降低了运算量。利用四阶累积量有效地扩展了阵列孔径,并且适用于任意加性高斯噪声环境。仿真结果验证了算法的有效性。 相似文献
307.
In this paper,a novel launch dynamics measurement system based on the photoelectric sensor pair is built.The actual muzzle time(i.e.a time duration that originates from the initial movement to the rocket's departure from the muzzle)and the muzzle velocity are measured.Compared with the classical methods,the actual muzzle time is obtained by eliminating the ignition delay.The comparative analysis method is proposed with numerical simulations established by the transfer matrix method for multibody systems.The experiment results indicate that the proposed measurement system can effectively measure the actual muzzle time and reduce the error of classical methods,which match well with the simulation results showing the launch dynamics model is reliable and helpful for further analysis and design of the MLRS. 相似文献