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排序方式: 共有109条查询结果,搜索用时 15 毫秒
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为解决装甲装备体系保障能力生成的关键技术难题,针对现有需求和装备保障体系仿真中心建设的实际情况,以装甲机械化部队为主要研究对象,论文主要研究内容包括:描述了装备保障体系概念,构建了装备保障体系结构框架;总结了适合装备保障体系的建模与仿真方法,采用分层建模、基于多Agent和基于UML的体系建模方法,建立了装备保障体系模型,并对模型进行了仿真;借鉴霍尔三维结构,建立了装备保障体系评估对象维、评估指标维和评估目标维,进行装备保障体系效能评估。通过研究,初步明确了装备保障体系的内涵,明确了适合装备保障体系的建模与仿真方法,具备一定的实用性和可操作性,能够为进一步推进装备保障体制改革、完善综合保障体系、创新保障模式、增强综合保障能力提供有力的理论支撑。 相似文献
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This study evaluated the reliability of pitch judgments as a basic step toward increasing interrater and intrarater reliability of multidimensional perceptual judgments of the speaking voice. Forty-five undergraduate university students studying speech/language pathology made piano-to-piano tone pitch matches and vowel-to-piano pitch matches using a computer software program. The mean percentage correct of piano-to-piano tone matches was 91.3% and of vowel-to-piano matches was 75.6%. Subjects who scored 100% correct were significantly faster at the pitch matching task. Further research of perceptual judgments of pitch and its contribution to multidimensional rating tasks is warranted. 相似文献
65.
GPU-accelerated real-time IR smoke screen simulation and assessment of its obscuration 总被引:1,自引:0,他引:1
With the growing demand for the Battlefield Environment Simulation (BES), IR smoke screen, which is computationally expensive and absolutely indispensable, should be modeled true to life and correct in its thermal radiation characteristics. This paper analyzes the features of an IR smoke screen, and represents an IR smoke screen model based on light extinction, particle dispersion and temperature attenuation, which is calculated by GPU and rendered to screen in real time. Thus a method considering both the real-life in profile and the real-time in efficiency is presented. Additionally, the comparison between the simulated results and the measured data is made to verify the correctness of the smoke screen’s obscuration, which illustrates the effect of its interference feature in an infrared scene. 相似文献
66.
软件寿命周期费用评价模型涉及到软件开发、使用和维护过程中各种资源最有效利用的权衡分析。由于软件开发不是一门严谨的精确科学,往往存在大量具有不确定性的需求以及许多未知和不确定因素,所有这些都给软件寿命周期费用评价带来模糊效用。本文将模糊理论应用于软件寿命周期费用的评价,给出了从评价属性模糊值的确定、模糊评价模型的建立,到模型求解和最优方案选择的模糊评价方法,并通过对一个算例的分析,证明了该模型的可行性。 相似文献
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Ewa Bergqvist 《The Journal of Mathematical Behavior》2007,26(4):348-370
Empirical research shows that students often use reasoning founded on copying algorithms or recalling facts (imitative reasoning) when solving mathematical tasks. Research also indicate that a focus on this type of reasoning might weaken the students’ understanding of the underlying mathematical concepts. It is therefore important to study the types of reasoning students have to perform in order to solve exam tasks and pass exams. The purpose of this study is to examine what types of reasoning students taking introductory calculus courses are required to perform. Tasks from 16 exams produced at four different Swedish universities were analyzed and sorted into task classes. The analysis resulted in several examples of tasks demanding different types of mathematical reasoning. The results also show that about 70% of the tasks were solvable by imitative reasoning and that 15 of the exams could be passed using only imitative reasoning. 相似文献
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利用2000~2016年登陆华南地区的24个台风样本的灾情与致灾源数据,建立台风灾害风险评估模型。首先,运用层次分析法和熵权法构建一种新的组合权重;然后,利用组合权重构建灾情指数序列和致灾源指数序列,计算每个台风灾害风险值,并将风险值从小到大划分为五个区间;最后,采用模糊随机方法建立华南地区台风灾害模糊风险评估模型,计算得到五个风险等级区间的模糊可能性,以此来表示各等级台风灾害发生的可能性大小。结果表明,基于组合权重构造的灾情指数序列与致灾源指数序列相关性较强;华南地区发生第二风险等级台风灾害的可能性最大,发生第五风险等级台风灾害的可能性最小,与实际情况较为吻合。 相似文献
69.
Under standard conditions, several studies assess uncertainty values for individual dosimetry for photons, but seldom for neutrons. The Thermoluminescent Dosimetry Laboratory (LDT) of the Instituto de Radioproteção e Dosimetria (IRD), Brazil, has been running a neutron individual monitoring service using two different albedo monitors. This paper presents a study of the contribution of relevant sources of uncertainty for neutron dose evaluation, for both systems (called System 1 and System 2), using a reference 241Am–Be field, at normal incidence. The combined and expanded uncertainties were calculated using GUM methodology and follows RP160 from the European Commission. This methodology was applied to calculate the uncertainties associated with the LDT assessment of neutron doses in the First Brazilian National Comparison on Measurements for Neutron Individual Monitors. The LDT participated in this comparison with its two systems, both presenting satisfactory performance. For System 1, at low neutron doses, the reproducibility of the apparent neutron dose is the more relevant source of uncertainty. However, for higher doses, the neutron calibration factor, NCF, becomes more important. For System 2, NCF is the main source of uncertainty for low and high doses. For occupational doses, the uncertainty will be much higher due to the need of additional correction factors, which depend on stray neutron field. 相似文献
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