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121.
基于离散降雨衰耗状态的卫星信道模型 总被引：1，自引：0，他引：1
针对Ka频段卫星信道中降雨衰耗的统计分布特点,建立了基于离散降雨衰耗状态的卫星信道模型,模型中各状态组成离散的Markov链并由其转移概率矩阵来表示,分析此模型下的信道误比特性能和数据包丢失性能。此模型能够适用于链路层以及高层通信协议。 相似文献
122.
为更有效地评价舰炮武器系统的射击能力和武器效能,本文以排队论为基础,建立了由舰炮武器系统与目标组成的排队系统服务概率数学模型,为综合评价舰炮武器系统的射击能力和系统效能提供参考依据。 相似文献
123.
This paper examines the impact of military expenditure on economic growth on a large balanced panel, using an exogenous growth model and dynamic panel data methods for 106 countries over the period 1988–2010. A major focus of the paper is to consider the possibility group heterogeneity and non-linearity. Having estimated the model for all of the countries in the panel and finding that military burden has a negative effect on growth in the short and long run, the panel is broken down into various groupings based upon a range of potentially relevant factors, and the robustness of the results is evaluated. The factors considered are different levels of income, conflict experience, natural resources abundance, openness and aid. The estimates for the different groups are remarkably consistent with those for the whole panel, providing strong support for the argument that military spending has adverse effects on growth. There are, however, some intriguing results that suggest that for certain types of countries military spending has no significant effect on growth. 相似文献
124.
Joanna R.Hall Olivia Matthews Timothy N.Volonakis Eric Liggins Karl P.Lymer Roland Baddeley Innes C.Cuthill Nicholas E.Scott-Samuel 《防务技术》2021,17(6):1833-1839
The human visual system is still an important factor in military warfare; military personnel receive training on effective search strategies, and camouflage that can effectively conceal objects and personnel is a key component of a successful integrated survivability strategy. Previous methods of camouflage assessment have, amongst others, used psychophysics to generate distinctiveness metrics. However, the population from which the human observers are drawn is often not well defined, or necessarily appropriate. In this experiment we designed a new platform for testing multiple patterns based on a camouflaged object detection task, and investigate whether trained military observers perform better than civilians. We use a two-alternative forced choice paradigm, with participants searching images of woodland for a replica military helmet displaying Olive Green, Multi Terrain Pattern, US Marine Pattern or, as a conspicuous control, UN Peacekeeper Blue. Our data show that there is no difference in detection performance between the two observer groups but that there are clear differences in the effectiveness of the different helmet colour patterns in a temperate woodland environment. We conclude that when tasks involve very short stimulus presentation times, task-specific training has little effect on the success of target detection and thus this paradigm is particularly suitable for robust estimates of camouflage efficacy. 相似文献
125.
This article elaborates on how structural, normative and functional pressures for change may challenge military organizational characteristics. We problematize theoretically and exemplify empirically what consequences these pressures can have on military organizational characteristics, arguing that they constitute major challenges for managing in particular normative pressures for change. The empirical examples suggest that bureaucratic, hierarchical, narcissistic and greedy traits of the organization are challenged by normative pressures such as value changes and normalization. Another source of challenge is professionalization processes. Structural challenges, on the other hand, are managed by the organization and do not seem to inhibit the workings of organizational characteristics. The plausibility probe conducted questions the sustainability of military organizational characteristics in their traditional disguise, in particular due to legitimacy concerns. It is suggested that future research should be directed towards analyzing how military organizations manage pressure for change and whether their characteristics are questioned. 相似文献
126.
基于TOPSIS的同步轨道通信卫星综合能力评估 总被引：1，自引：0，他引：1
同步轨道通信卫星具有诸多优势,现有的通信卫星星座大多由多颗此类卫星组成。星座中的每颗卫星对特定作战区域的影响不尽相同,提出了采用逼近理想点法对同步轨道通信卫星综合能力进行了评估,为了解星座中各颗卫星的相对重要性提供了依据。首先,介绍了评估过程,根据同步轨道通信卫星特点提出了评估指标体系;其次,重点介绍了逼近理想点法运用的模型;最后通过仿真实例,证明这种评估方法运用于同步轨道通信卫星综合能力评估可行。 相似文献
127.
128.
战场通信网络消息处理模型研究 总被引：2，自引：0，他引：2
针对战场通信网络建模需求,基于 EBI建模框架,提出了面向实体的战场通信网络建模方法,探讨了战场通信网络实体模型的组成结构.重点分析了战场通信网络消息处理模型的作用和功能,给出了消息处理模型的仿真工作流程,对消息处理模型中的消息列表、通信事件列表、网络路由算法进行了阐述,并结合通信节点实体模型中的消息缓冲器,探讨了消息处理模型管理和维护通信事件列表的方法. 相似文献
129.
130.
Harald Høiback 《战略研究杂志》2013,36(6):879-900
‘Doctrine’ has been part of military vernacular for at least a century. Nonetheless, it is a concept which is rather under-explored. The aim of this article is thus to break doctrine down into its component parts in order to grasp what a military doctrine actually is. Thereafter, the article points out different ways to utilise doctrine as a military devise. A doctrine cannot be, or rather should not be, all things to all men. On the contrary, doctrine can be a tool of command, tool of education or a tool of change. The main upshot of the article is that the future of doctrine is far brighter than its critics want us to believe. 相似文献