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601.
602.
高轨预警卫星威胁评估是导弹作战指挥辅助决策的重要环节,可以为指挥员的太空目标选择提供依据。在分析其威胁要素特征的基础上,提出了采用“聚合模型”开展威胁评估的方法,并给出了威胁评估步骤。通过分析美国高轨预警卫星的工作模式及作战流程,选取了扫描探测、凝视跟踪及外部等三个方面的关键性威胁要素,并构建了各要素的评价函数模型。基于上下层威胁要素之间关系的不同,给出了两种不同的聚合模型,采用该模型分析了所选要素之间的聚合关系,得到了高轨预警卫星威胁评估模型。最后通过实例计算,验证了该评估方法的可行性和实用性。 相似文献
603.
604.
在对联合作战目标协同研究内容分析的基础上,提出了多任务部队与多作战目标的协同目标分配模型,其融合了目标综合价值、目标打击有效性、目标威胁适配度、目标类型匹配、目标距离匹配等因素。通过对各因素量化并将协同目标分配模型转换为指派问题进行求解,验证了分析方法的可行性。 相似文献
605.
This paper analyzes time-sensitive data on a humanitarian crisis in the Middle East. It aims to assess the impact of the steep influx of Syrian refugees into Jordan on the country’s labor market since the onset of the conflict in Syria (March 2011). As of August 2014, nearly three million registered Syrians have sought refuge in neighboring countries (Lebanon, Jordan, Iraq, and Turkey), according to the United Nations High Commissioner for Refugees. Jordan and Lebanon are hosting the majority of them. This paper utilizes data regarding unemployment rates, employment rates, labor force participation, the number of refugees, and economic activity at the level of governorates. The vector autoregressive methodology is used to examine time series data from the most affected governorates in Jordan. The empirical results of Granger causality tests and impulse response functions show that there is no relationship between the influx of Syrian refugees and the Jordanian labor market. Our results are verified through a set of robustness checks. 相似文献
606.
607.
攻防对抗中弹道仿真的设计与实现 总被引:2,自引:0,他引:2
在攻防对抗仿真试验中,为了验证导弹性能、分析导弹战术指标,需要进行导弹群复杂环境下的弹道仿真试验,这给仿真实现带来了一定的困难。针对这一困难,在详细分析了六自由度下的弹道仿真的复杂情况的基础上,利用分布式计算的原理和标准,探讨了分布式仿真在导弹群复杂环境下弹道仿真中的应用方法及实现途径。 相似文献
608.
609.
Ammonium nitrate and fuel oil (ANFO) based explosive is a classic example of non-ideal high explosives. Its detonation is characterized by a strong dependence of detonation parameters on explosive charge diameter, presence and characteristics of confinement, as well as incomplete consumption of explosive at the sonic point.In this work we propose a detonation model based on the Wood-Kirkwood (WK) theory coupled with the thermochemical code EXPLO5 and supplemented with reaction rate models. Our objective is to analyze the validity of the model for highly non-ideal ANFO explosives, with emphasis on effect of reaction rate models.It was found that both single-step and two-step pressure-based models can be calibrated to reproduce experimental detonation velocity-charge radius data of ANFO at radii significantly above the failure radius (i.e. for D/Did > ∼0.6). Single-step pressure-based model, with the pressure exponent equal to 1.4, proved to be the most accurate, even in the vicinity of the failure radius. The impact of the rate models is most evident on temporal (and spatial) distribution of flow parameters in detonation driving zone, especially when it comes to the conversion and width of detonation driving zone. 相似文献
610.
In order to accurately describe the transverse relaxation characteristic and stress relaxation modulus of HTPB coating during pre-strain thermal aging process, a one month thermal aging test was carried out at 70 C with pre-strain of 0%, 3%, 6% and 9%, respectively. The low-field 1H NMR and stress relaxation modulus tests were carried out for HTPB coating at different aging stages. The stress relaxation model considering the molecular chains was proposed according to the changes of crosslinking chain and dangling chain of HTPB coating during pre-strain aging. The results showed that with the increase of aging time, the decay rate of transverse relaxation curve became faster, the transverse relaxation time decreased, the value of combined parameter qMrl increased, the proportion of crosslinking chain decreased, while the proportion of dangling chain increased. Moreover, the stress relaxation modulus increased, the crosslinking network structure of HTPB coating became denser and the degree of cross-linking increased. At the initial aging stage, the pre-strain will destroy the crosslinking network structure of HTPB coating to a certain extent. With the increase of aging time, the effect of pre-strain will gradually weaken and the influence of aging on materials will gradually increase. The correlations between the stress relaxation model considering the molecular chains and the test results were more than 0.9950, which can accurately describe the stress relaxation modulus of HTPB coating during the pre-strain thermal aging process. 相似文献