贴片机脱机编程的快捷方法

SMT生产线中的大多数加工设备均为数控设备。它们编程所需要的大多数特征数据均可从CAD设计系统中得到。文章介绍了如何从CAD设计系统中导出X、Y坐标数据,并转换成贴片数据的方法和思路,以期引起更多的同行加入到这方面的研究中。     

Disciplinary and linguistic considerations for academic Web linking: An exploratory hyperlink mediated study with Mainland China and Taiwan

The Web has become an important means of academic information exchange and can be used to give new insights into patterns of informal scholarly communication. This study develops new methods to examine patterns of university Web linking, focusing on Mainland China and Taiwan, and including language considerations. Multiple exploratory investigations into Web links were conducted between universities in these two places. Firstly, inlinks were counted to each university Web site from its national peers using four alternative Web document models. The results were shown to correlate significantly with research productivity in Taiwan but not in the Mainland, although in the latter case less reliable institutional data could have been the cause. For Taiwan, this is the first evidence of a scholarly association with academic linking for a non-English speaking region. It was then ascertained that the same link counts associated more strongly with scientific than social scientific research productivity in Taiwan. This confirms the general assumption of greater Web use by the hard sciences. We then investigated Taiwan-Mainland university cross-links, and found that although English is extensively used on the Web, there was no evidence that it was the language of preference for informal scholarly communication between the two areas. This revised version was published online in August 2006 with corrections to the Cover Date.     

Characteristics of low-leakage deep-trench diode for ESD protection design in 0.18-/spl mu/m SiGe BiCMOS process

This paper proposes a novel low-leakage BiCMOS deep-trench (DT) diode in a 0.18-/spl mu/m silicon germanium (SiGe) BiCMOS process. By means of the DT and an n/sup +/ buried layer in the SiGe BiCMOS process, a parasitic vertical p-n-p bipolar transistor with an open-base configuration is formed in the BiCMOS DT diode. Based on the two-dimensional (2-D) simulation and measured results, the BiCMOS DT diode indeed has the lowest substrate leakage current as compared to the conventional p/sup +//n-well diode even at high temperature conditions, which mainly results from the existence of the parasitic open-base bipolar transistor. Considering the applications of the diode string in electrostatic discharge (ESD) protection circuit designs, the BiCMOS DT diode string also provides a good ESD performance. Owing to the characteristics of the low leakage current and high ESD robustness, it is very convenient for circuit designers to use the BiCMOS DT diode string in their IC designs.     

Using buried capacitor in LTCC-MLC balun

A novel chip-type ceramic balun designed in the 2.4 GHz ISM band frequency is presented. A buried capacitor is included in the balun, so that the length of the coupled transmission lines can be reduced and can be designed very easily. A meander or spiral broadside coupled-line is adopted to realise the proposed LTCC multi-layer balun. The measured performances of phase and amplitude balance for this LTCC-MLC balun show a good match with computer simulation     

一种实现最佳用户检测的非线性优化神经网络

本文提出并讨论了实现码分多址（CDMA）系统上最佳多用户检测（MUD）的一种神经网络方法。该方法通过将最佳多用户检测视为非线性优化组合问题，利用神经网络能有效求解非线性优化问题的优势，导出了一种非线性优化神经网络来实现最佳多用户检测，理论分析和计算机模拟表明，所提出的神经网络具有可实时应用的动态性能和较传统方法优越得多的误码率性能和抗多址干扰的性能。     

放置过滤器浇注系统的设计

综述了常用的网型、芯型、泡沫陶瓷过滤器的研究和应用情况。指出应根据过滤器类型，确定其在浇注系统中的安放位置并相应改变该处的结构和截面积，以便在使用过滤器净化金属的同时，保证充型速度不变。     

应用于生物医学的光声光谱技术的改进和实验研究

改进的光声光谱归一化技术，避免了普通的分光法归一化光声光谱技术中分束镜以及锁相放大器动态范围的影响和限制，实现宽光谱范围内准确的光谱测量。氙灯光源功率起伏用修正项修正，误差在5％以内，实现各次实验数据的可比性。     

邻—(4—乙基苯甲酰基)苯甲酸的研究

本文阐述了通过Friedel-Crafts反应合成邻-(4-乙基苯甲酰基)苯甲酸的方法.研究了影响产物质量的因素,提出了适宜的工艺条件.     

本地七号公共信令网实施的若干问题

本文主要讨论本地七号公共信令网实施的若干问题，如信令转发点的设置，链路设置和路由选择，话路网和信令网的关系，不同制式七号公共信令的互通问题等。