基于Matlab GUI的数字滤波器设计及其应用

基于数字信号处理原理,在分析数字滤波器设计理论和Matlab编程技术及其GUI图形用户界面设计的基础上,开发了具有交互式特点的数字滤波器软件,界面操作简单方便,可以根据需要选择滤波器类型,输入相关参数,然后选择相应的功能按钮,就可以得到滤波器的特性参数,并进行滤波器的性能分析,打破了以往滤波器设计过程中大量繁琐的数值计算问题,为数字滤波器的设计和应用提供了一个有效的辅助工具。     

Atropine and exercise-induced bronchoconstriction

Six asthmatic children were studied to determine whether supplemental, parenteral atropine would increase the effects of bronchodilation and protection against exercise-induced bronchoconstriction after maximal effects had been achieved by inhalation. First, we determined the amount of inhaled atropine sulfate that would give maximal bronchodilation for each patient at rest. This quantity of atropine was designated as "A." Then all subjects exercised for five sessions with the following pre-exercise treatments in a random order: (a) inhaled distilled water plus intramuscular (IM) saline solution; (b) inhaled A dose of atropine plus IM saline solution; (c) inhaled distilled water plus 0.35 mg IM atropine; (d) inhaled A dose of atropine plus 0.35 mg IM atropine; and (e) inhaled double the A dose plus IM saline solution. The results showed that the combination of inhaled and IM atropine had the greatest bronchodilation effect and the greatest protection against exercise-induced bronchoconstriction. Atropine inhalation alone (A dose) or IM injection (0.35 mg) was not as effective in bronchodilation or in alleviation of exercise-induced bronchoconstriction. Doubling the dose of inhalation (2A) did not increase the effects of the A dose. These results support the hypothesis that inhaled atropine does not reach all the airways where cholinergic receptors are present.     

Feasibility study of the application of voltage contrast to printed circuit board

Voltage contrast (VC) has been a powerful tool for the failure analysis of integrated circuits and multichip module. As the packing density of printed circuit board (PCB) is increasing, conventional failure analysis methods to detect open or short circuit in PCBs are no longer adequate, and voltage contrast method could be a method for this purpose. However, unlike the cases of integrated circuits and multichip module, there are many areas in PCB that will produce serious charging effect when examine under the scanning electron microscope. One of the areas is the presence of solder mask on PCB.This work examines the feasibility of using voltage contrast for PCB failure analysis. Specially designed PCB is used for experimentation, and it is found that positive bias on one track and zero bias on another copper track provide a better image contrast as compared to negative and zero biases on the tracks. Also, the variation of the image contrast with different spacing between inter copper tracks has studied. It is found that the variation depends on the presence of solder mask and its location. The variation can be very different for negative bias case as compared to the positive bias case.Finite element analysis is also performed to explain the experimental observations. All the observations can be well explained by the charging effect of the solder masks. The charging effect of solder mask is indeed very significant in affecting the image contrast, and it could reduce the contrast to almost zero in some cases.     

山西移动NGN建设探讨

首先着重分析了山西移动本地NGN的需求。阐述了山西移动NGN建设需要考虑的因素．最后就山西移动NGN的网络建设策略提出了具体的建议。     

基于GIS的道路事故黑点聚类应用研究

由于地理信息系统中数据的多样性和空间复杂性,在GIS数据空间挖掘时原有的挖掘算法会遇到一些新问题。本文针对城市道路网中交通事故黑点发掘问题,对基于密度的DBSCAN算法进行改进,使改进后的算法能够确保聚类仅在连通空间内进行。最后以某市交通事故数据为例对该方法进行验证,实验结果表明此方法是有效的。     

基于学习的多议题协商

随着在线交易越来越普遍,如何有效地将先进的agent技术运用于电子商务协商领域,已经成为经济学家和计算机学者共同研讨的一个主要方向。文中从买方agent的观点出发,在协商过程中采用贝叶斯学习机制进行预测和更新对方agent的信念,使得每个agent通过学习来协调自身的行为,从而缩短了协商时间,提高了协商效率,更能有效地完成协商目的。并实验说明了其可行性。     

现代电炉炼钢技术发展趋势

综述国内外电炉炼钢技术发展趋势。就国内外电弧炉技术现状度发展趋势进行了讨论，总结了目前电弧炉发展的短期目标、长期目标。     

混合炸药造型粉的超临界流体反溶剂过程制备

将超临界流体反溶剂（Supercritical FluidAnti-solvent，SAS）过程用于炸药表面包覆．采用氟橡胶F2602为包覆材料．乙酸乙酯为共溶剂,与炸药形成悬浮液：超临界CO2为反溶剂,研究了体系温度、压力和进气速率对炸药包覆效果的影响．经过对包覆后样品的性能测定和SEM分析．结果表明：体系温度是影响包覆效果的最关键的工艺参数，压力和进气速率也有一定影响．通过合理调节以上工艺参数可以获得较佳的包覆效果.     

蓝钨制取超细钨粉的研究

以蓝钨为原料,通过氢还原制取超细W粉末,研究了还原温度、装舟量和氢气流量对制取W粉粒度的影响。结果表明:在适当的工艺条件下,使用蓝钨可以制得超细钨粉。     

对二乙氨基苯基亚甲基若丹宁固相萃取光度法测定氰化渣中铂的研究

根据对二乙氨基苯基亚甲基若丹宁 (DEABR)与铂的显色反应及C18固相萃取小柱对显色络合物的固相萃取 ,并结合微波溶解样品 ,建立了一种测定氰化渣中铂的方法。氰化渣样品用微波密闭溶解 ,试液中的铂在pH为 2 .0的氯乙酸 -氢氧化钠缓冲介质中、乳化剂 -OP存在下与DEABR生成 2∶1稳定络合物 ;该络合物可被C18固相小柱萃取富集 ,用氮 -氮二甲基甲酰胺 (DMF)洗脱 ,富集倍数可达 5 0倍 ,洗脱液定容后用光度法测定 ;该络合物λmax=5 45nm ,ε =8.85×10 4 L/ (mol·cm) ,铂质量浓度在 0 .0 1～ 2 .0mg/L内符合比尔定律。该方法用于氰化渣中铂的测定 ,结果令人满意。