土木工程专业安装课群组课程体系设置的研究与实践

文章介绍了如何在土木工程专业大平台下办好安装工程课群组,克服多年来安装工程课群组存在的课程门类多,但理论深度与相互联系不够的弱点。提出了课程体系改造的思路及实践的效果。     

装甲车辆传热仿真研究

本文提出了装甲车辆全车传热的仿真方法,应用集总参数法建立了装甲车辆传热的数学模型,编制了计算程序.实际计算了某型号履带装甲输送车海上航行时,发动机处于稳态条件下的热状况,计算出各部分(部件)的温度及散热特性.计算结果与试验值符合较好.     

Trusted Next Generation Internet and Its Development

The ongoing research on secure and trustworthy issues in next generation Internet technology is still insufficient. China has achieved some progress in the field of the trusted next generation Internet. Under the support of the National High Technology Research and Development Program of China (863 Program), Tsinghua University and other units have completed the program named "Research on Critical Technologies and Demonstration Applications of the Trusted Next Generation Internet", which targets the secure and trustworthy problems existing in the current Internet. With focus on tackling the technical problem of authentic address access in the Internet, a prototype system for trusted Internet infrastructure, security service and typical applications are designed and implemented. It is expected that the trusted next generation Internet will support the trusted computer network, trusted telecom network and trusted broadcast & TV network applications.     

基于USB2.0MIT-BIH心电数据回放系统的设计

设计基于USB2.0的D/A转换模块,文中对模块的主要芯片、主要原理、接口函数及主要性能进行了介绍.通过取一心电数据通过vc编程将其进行D/A转换,输出波形与原始波形进行比较,较好的实现了回放功能.由此可见,该模块的性能指标达到了设计要求.心电数据回放很好的实现,为一系列心电算法的仿真实践及实时心电监护仪的研制打好了基础.     

SOI LDMOSFET的背栅特性

在绝缘体上硅衬底上,制备了栅长为0.5μm的低势垒体接触结构和源体紧密接触结构的横向双扩散功率晶体管.详细研究了器件的背栅特性.背栅偏置电压对横向双扩散功率晶体管的前栅亚阈值特性、导通电阻和关态击穿特性均有明显影响.相比于源体紧密接触结构,低势垒体接触结构横向双扩散功率晶体管的背栅效应更小,这是因为低势垒体接触结构更好地抑制了浮体效应和背栅沟道开启.还介绍了一种绝缘体上硅横向双扩散功率晶体管的电路模型,其包含前栅沟道,背栅沟道和背栅偏置决定的串联电阻.     

HSUPA组网性能初探

分析了HSUPA的组网覆盖、容量性能,以及它对R99组网性能的影响、最后提出了一些HSUPA规划组网方面的建议。     

A novel common single primer multiplex polymerase chain reaction (CSP‐M‐PCR) method for the identification of animal species in minced meat

BACKGROUND: Minced meat species adulteration is a severe problem. In this study a common single primer multiplex polymerase chain reaction (CSP‐M‐PCR) method was applied to the identification of five species (chicken, cattle, sheep, pig and horse) in minced meat products. CSP was designed as a common adapter at the 5′‐end of species‐specific reverse primers and employed in giving different length fragments from the respective meat species. RESULTS: Species‐specific DNA fragments could be identified in a single PCR reaction by mixing CSP, Chicken‐R, Cattle‐R, Sheep‐R, Pig‐R and Horse‐R primers in the ratio 1:0.01:0.01:0.01:0.01:0.10 (where ‘1’ represents 0.5 mmol L^?1). The specific DNA fragments could be efficiently amplified by CSP‐M‐PCR with > 5 µmol L^?1 species‐specific primers, except for 50 µmol L^?1 Horse‐R. A detection limit of 0.5 g kg^?1 was determined for both single species of minced meat and all species of five kinds of minced meat. CONCLUSION: The CSP‐M‐PCR method simplified the PCR reaction system and removed the inconsistent amplification efficiency from different primers. This highly sensitive, reproducible and rapid method could potentially be used as a screening or identifying assay to test for the presence of species or ingredients in minced meat and other meat products. Copyright © 2008 Society of Chemical Industry     

A study on robust adaptive modulation controller for TCSC based on COI signal in interconnected power systems

This paper proposes a novel robust adaptive modulation controller (RAMC) for thyristor controlled series capacitor (TCSC) in interconnected power systems to damp low frequency oscillation. The main idea of the controller is to drive the area centers of inertia (COI) to a stable equilibrium point and keep system synchronization. COI-coordinate-based model is derived first. Then RAMC for TCSC is derived using back-stepping method with COI dynamic signals from WAMS. The new controller performance is tested through a three-area power system and the simulation results show clearly that the new controller using COI signals has superior performance as compared with the conventional controller.     

微晶蜡优化生产研究

采用双反应器一段串联加氢流程,在第一反应器入口温度330℃、第二反应器入口温度270℃、反应氢分压13.0MPa、体积空速0.2h^-1和氢蜡体积比750的加氢条件下,得到接近食品级质量要求的微晶蜡产品。经过进一步改良优化后的微晶蜡,性能可与进口优质产品媲美。     

油水两相绝热和冷却流型与换热特性研究

通过自制热电偶、自制双平行电导探针、Labview编程系统和IMP温度采集系统等测量手段获取油水两相流内部的相分布特征,分析流型种类和流动参数与换热系数的相互影响。结果表明,管外冷却换热会影响流型分布,管外冷却换热过程中水包油、混合界面分层流以及油包水这三种流型所占的范围变小,但分层流、油包水&水包油以及水包油&水流型在流型图上所占范围变大,相邻流型之间的转化分界线偏上,向更大油速和水速趋势发展,并且换热系数与流型和流速密切相关,低流速下主要受流速的影响,而高流速下主要受流型的影响。