面向大规模定制的虚拟设计研究

综述了大规模定制的范围经济性和面向大规模定制的基本设计方法，并提出了一个虚拟设计框架，该框架改变了传统的设计模式，利用先进的设计方法学和仿真支撑技术为产品开发提供了最大柔性和敏捷性。同时，它提供了一个多学科合作的设计环境，用户直接参与进设计循环中。最后，结合新型剑杆织机的开发，展示了一个能够支持新产品快速成功开发的虚拟设计环境。     

A collaborative platform for complex product design with an extended HLA integration architecture

How to integrate the heterogeneous, autonomous models in a distributed environment, running on Internet, integration based on multilayer federation architecture and simulation resources dynamic reuse are the major difficulties for complex product collaborative design and simulation. An extended HLA-based collaborative simulation platform for multidisciplinary collaborative design is proposed. The architecture of platform is first given. The idea and realization of four key technologies, the dynamic creation of simulation federation based on resource management federation (RMF), HLA enabled template, collaborative simulation algorithm based on stage-data synchronization and TH_RTI, an extensible HLA runtime infrastructure (RTI), which is a web enabled RTI and can be used at Internet, are emphasized. Finally, an industry case is given. The demonstration of these prototype systems shows that extended HLA integration architecture is effective infrastructure for multidisciplinary collaborative modeling and simulation (M&S).     

基于Internet的协同产品开发中基于Agent的工作流管理系统框架

基于Internet实现协同产品开发是虚拟制造技术和并行工程思想的融合,而实现它需要一个计算机系统提供有效的管理和支持。文章提出了一个新的框架,在分布式对象技术的基础上,充分发挥工作流技术在任务管理方面的优势和代理技术在知识表达、事务处理、智能性能方面的优势,以代理技术为框架基础,以工作流技术为核心,将这两种技术进行有机结合,使得工作流管理系统能够在Internet的环境下透明地管理协同产品开发中的工作流、资源和数据,从而达到支持协同产品开发的目的。     

Modification of exposure conditions by the magnetic field configuration in helicon antenna-excited helium plasma

Modification of exposure conditions downstream in the diffusion chamber has been performed in helicon antenna-excited helium plasma by adjusting the magnetic field(intensity and geometry).In the inductively coupled mode(H mode), a reduction in ion and heat fluxes is found with increasing magnetic field intensity, which is further explained by the more highly magnetized ions off-axis around the last magnetic field lines(LMFL). However, in helicon wave mode(W mode), the increase in magnetic field intensity can dramatically increase the ion and heat fluxes.Moreover, the effect of LMFL geometry on exposure conditions is investigated. In H mode with contracting LMFL, off-axis peaks of both plasma density and electron temperature profiles shift radially inwards, bringing about a beam with better radial uniformity and higher ion and heat fluxes. In W mode, although higher ion and heat fluxes can be achieved with suppressed plasma cross-field diffusion under converging LMFL, the poor radial uniformity and a small beam diameter will limit the size of samples suitable for plasma irradiation experiments.     

基于杂波密度估计的联合概率数据互联算法

联合概率数据互联(JPDA)算法能很好地解决密集环境下的多目标跟踪问题。在该算法基础上,人们又提出了多传感器联合概率数据互联(MSJPDA)算法和一些基于JPDA的修正算法。在联合概率数据互联算法中,有一个很重要的参数就是杂波数密度(或波门内虚假量测期望数),然而在许多实际情况中,这个参数是很难获取的。针对这一问题,提出了一种修正的联合概率数据互联算法,该算法通过实时地调整这一参数来获得对目标较为准确的估计结果。最后,给出了算法的仿真分析。     

考虑电解槽动态特性的电-氢-化工耦合系统最优运行方法

考虑到电解槽动态运行及化工系统H2 的需求,以风光-氢-化工耦合系统总费用最小为目标,提出了风光-氢-化工耦合系统最优运行方法。通过建立电解槽多状态转换模型,刻画电解槽冷热备用状态及非线性输出特征。为了应对系统的化工过程中H2需求的波动性要求,构建H2公共工程的波动性约束。通过算例仿真对比分析了电解槽动态运行及化工过程的H2需求波动性要求对耦合系统运行策略及收益的影响。仿真结果表明,所提运行模型协调优化了电解槽启停、风光出力波动与化工系统氢需求,实现了弃电量的优化,提升了耦合系统的整体运行收益。     

一种高性能的亚阈值CMOS电压基准

基于0.18 μm CMOS工艺设计了一种高性能的亚阈值CMOS电压基准。提出了一个电压减法电路,将两个具有不同阈值电压且工作在亚阈值区晶体管的栅源电压差作为电压基准输出。所提出的电压减法电路还可以很好地消除电源电压变化对输出基准的影响。后仿仿真结果表明,所设计的电压基准在0.55~1.8 V电源电压范围内,线性灵敏度为0.053%/V~0.121%/V;在-20 ℃~80 ℃范围内,温度系数为9.5×10-6/℃~3.49×10-5/℃;在tt工艺角、0.55 V电源电压下,电源抑制比为-65 dB@100 Hz,功耗为3.7 nW。芯片面积为0.008 2 mm²。该电路适用于能量采集、无线传感器等低功耗应用。     

数据网格中的双向排序及其随意修改

总结了在DataGrid中进行正、反双向排序的两种方法：分别利用Attributes属性和利用ViewState来保存排序表达式和排序方向,更方便用户浏览查阅;给了点击DataGrid的任一位置以选中一行的方法,更方便用户操作;还给出从表单输入控件修改（更新或删除）DataGrid中所选择记录行的方法,以保证数据有效性验证。     

In situ efficiency of filters in residential central HVAC systems

High-efficiency filtration in residential forced-air heating, ventilation, and air conditioning (HVAC) systems protects equipment and can reduce exposure to particulate matter. Laboratory tests provide a measure of the nominal efficiency, but they may not accurately reflect the in situ efficiency of the filters because of variations in system conditions and changes in filter performance over time. The primary focus of this paper is to evaluate the effective filtration efficiency, which is inclusive of any loading and system impacts, in 21 occupied residential homes through in-duct concentration measurements. We considered the role of filter media by testing both electret and non-electret media, as well as the role of loading by considering new and used filters. The results show that filters with higher nominal efficiency generally had higher effective filtration efficiency in the same home. In terms of performance change, there is no significant difference in efficiency between initial and 3-month non-electret filters, but the efficiency of electret filters generally decreased over time. However, both nominal efficiency and performance change were vastly overshadowed by the wide variety in loading and system conditions across homes, making it hard to predict filter efficiency in a given home without in situ measurements.     

空间红外大口径折射式低温镜头设计与验证

针对目标探测类空间红外相机大范围成像、高灵敏度探测、高精度定位等应用需求,文中提出采用像方远心光路和低温光学技术结合的解决方案,设计了物方视场角8°×8°、入瞳口径265 mm、工作温度200 K的像方远心折射式光学系统。镜头最大口径280 mm,采用多级分散的弹性支撑设计,解决大口径低温透镜装框、透镜组件支撑和镜头整体安装各环节的热应力卸载问题。在保证高刚度和低漏热的情况下,使低温下透镜的热应力对镜头能量集中度的影响降低到可接受范围内。镜头完成装调及室温下像质确认后,进行了力学振动试验,并将其制冷到200 K水平测试像质,测试结果表明,镜头能量集中度达到轴上75%,边缘视场72%。