共查询到20条相似文献,搜索用时 840 毫秒
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《中国计量学院学报》2017,(3):380-387
在无线电综合测试仪的设计中,频谱扫描是一项基础技术.将需要扫描的频谱划分成子带,进而提出了一种通过在模拟前端采用可变频率本振的混频器和低通滤波器实现子带信号分离,然后对子带信号进行采样并且变换到频域,最后将所有子带频谱拼接获得完整频谱的技术.为了实现该技术,设计了一个由软件无线电(Software-defined Radio,SDR)接收机和数字信号处理片上系统(System on Chip,SOC)组成的软件无线电平台.随后,在基于该平台实现的综测仪原型上对频谱分析技术进行了验证.仿真和实验表明,该方法和原型样机能够对0~6 GHz范围的频谱进行扫描,同时具有较低的噪声水平和较好的动态范围,且能够提供相位谱,因而适用于嵌入式频谱仪和无线电综测仪的应用场合. 相似文献
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电子节气门硬件在环仿真测试方法研究 总被引:3,自引:0,他引:3
电子节气门被广泛地应用于汽车发动机中,其设计越来越受到重视.采用硬件在环仿真测试可大大缩短电子节气门的研发、标定时间.借助汽车电控系统快速原型开发环境(MACS565),建立了电子节气门的硬件在环仿真测试平台.利用Matlab/Simulink建立了仿真测试模型,实现了电子节气门硬件在环仿真和性能测试.利用此平台完成了某型号电子节气门传感器输出特性的测试方法研究及相关参数的测定工作.该测试平台为电子节气门新产品的开发与性能检测提供了测试手段,同时可作为产品在线质量检测系统的原型. 相似文献
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Applications of computer simulation methods, such as atomistic simulation, coarse-grain simulation and mesoscopic simulation, on surfactant assemblies at the interface, surfactant aggregates, and the surfactant/polymer assemblies were summarized based on our works. And the development and prospect of applying computer simulation to study self-assembling surfactant systems were also referred to. 相似文献
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Lina A.M. Huertas Quintero Andrew A. West Diana M. Segura Velandia Paul P. Conway Anthony Wilson 《国际生产研究杂志》2013,51(1):45-68
Low-volume high-complexity printed circuit board manufacturing is a highly dynamic domain because of prevailing global pressures. In such an evolving environment, quality issues caused by manufacturing defects are the major concern. The generation, detection and elimination of those defects further impact customer requirements and demands. Current practices in terms of identification and solution of quality issues have three major drawbacks: (i) the metrics used are not meaningful; (ii) several manual operations are involved; and (iii) there is no significant decision support. A novel integrated simulation tool for quality support in low-volume electronics manufacturing that overcomes these weaknesses is presented in this paper. The simulation tool supports current needs in the domain, i.e. knowledge capitalisation, waste reduction, right-first-time performance and agility, as well as the domain customer requirements, i.e. lead time, cost, quality and reliability. Quantitative results from a case study are presented as evidence of the usefulness of the tool in a real context. The results show that the approximately 80% non-value-added cost for the product studied is due to just two types of manufacturing defects. This outcome is key for root cause analysis based not only on defect quantity. 相似文献
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Computer simulation has been used widely in many industries for many applications. A simulation model mimics a real world system, enabling an investigation of its operation. More recently simulation models have incorporated a visual display and interactive features to aid understanding and enhance the investigation. Computer simulation has many potential uses in quality and reliability engineering, for instance, modelling equipment failures, quality control strategies, maintenance requirements and operational logistics. A case study shows how simulation has been used to study the throughput, flexibility and robustness of a manufacturing plant design. Alternative simulation software packages are briefly discussed. 相似文献
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本文总结了各种舰船辐射噪声特性及其模拟产生原理技术方法 ,重点分析研究了常用的水声换能器模拟方法的各种模拟技术原理、技术实现及其应用特点 ,对相关设备的研究有一定的参考价值。 相似文献
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目的利用蒙特卡洛法模拟分析基体PE的结构变化对其吸附乙烯的影响,从微观角度展现新型活性包装材料PE/分子筛膜对乙烯的吸收过程,揭示微观吸收机理。方法通过MaterialsStudio软件分别构建不同聚合度和分子链数目的 PE/分子筛高分子模型,采用蒙特卡洛法模拟PE/分子筛体系对乙烯的吸附过程,并绘制吸附等温线来分析吸附效果。结果 PE/分子筛体系对乙烯的吸附量随聚合度的增加而减小,随分子链数目的增加而增加;达到吸附平衡后,吸附量在一定范围内存在明显的波动。结论基体结构对活性包装材料PE/分子筛膜的吸收效果有较大的影响。在相同条件下,以低聚合度和多分子链数目结构形成的PE/分子筛包装体系更有利于对乙烯的吸附,且该吸附平衡是一个吸附与脱吸同时发生的动态平衡。 相似文献
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室内气流组织数值模拟及仿真软件 总被引:1,自引:0,他引:1
不同的气流组织形式对室内空气品质会产生影响,用CFD技术模拟气流组织具体影响,将室内空气品质的研究体现在工程设计上是必要的。本文就数值方法和相关的气流组织模拟软件作了分析和介绍,并说明了在应用过程中的步骤。 相似文献
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A novel subset simulation algorithm, called the parallel subset simulation, is proposed to estimate small failure probabilities of multiple limit states with only a single subset simulation analysis. As well known, crude Monte Carlo simulation is inefficient in estimating small probabilities but is applicable to multiple limit states, while the ordinary subset simulation is efficient in estimating small probabilities but can only handle a single limit state. The proposed novel stochastic simulation approach combines the advantages of the two simulation methods: it is not only efficient in estimating small probabilities but also applicable to multiple limit states. The key idea is to introduce a “principal variable” which is correlated with all performance functions. The failure probabilities of all limit states therefore could be evaluated simultaneously when subset simulation algorithm generates the principal variable samples. The statistical properties of the failure probability estimators are also derived. Two examples are presented to demonstrate the effectiveness of the new approach and to compare with crude Monte Carlo and ordinary subset simulation methods. 相似文献