一种小功率风电系统能量自动转化装置

本文介绍了一种由永磁励磁或电励磁的同步发电机，三相二极管整流桥，Buck型直流斩波器等组成的，负载为蓄电池的风电系统。其中，直流斩波器和电池由微型数字控制器进行控制。在Matlab-Simulink环境下对此系统进行了数字仿真。     

不锈钢化学转化膜显色工艺研究

通过正交实验法对不锈钢化学转化膜显色工艺规律及工艺参数进行试验研究，对各种硬化方法进行了对比试验。     

Increasing the up-link CW interference immunity of non-coherent direct sequence pseudonoise (DSPN) reception with on-board processing

The adaptive threshold A/D converter is by now a familiar technique for increasing the CW interference immunity of coherently detected direct sequence pseudonoise (DSPN) spread-spectrum signals, especially where the frequency of the CW interferer may be changing so rapidly and over such a large portion of the signalling bandwidth that well known spectrum excision techniques prove ineffective. The present paper extends the theory to the case of non-coherent reception of direct sequence pseudonoise (DSPN) signals. The A/D converter is found to perform well in both CW and Gaussian interference. Conversion gain is seen to persist even if the interference is intentionally pulsed at an optimally reduced duty factor (from the interferer's point of view) in the attempt to confuse the adaptive threshold. The specific case of 32-chip data symbols is treated, wherein the adaptation is applied strictly to individual symbols. In some cases these restrictions will actually improve performance.     

露天矿山空载重型汽车柔性路面计算的探讨

分析了空载重型汽车柔性路面轴次换算与路面厚度计算的问题，提出了轴次换算以空载后轴为标准轴载，路面厚度计算应计入空载前轴的作用并采用空载后轴的参数；将空载与重载的理论弯沉系数、路面厚度建立了联系，从而得出了空载时路面厚度约为重载时１／２的结果。     

On the performance bounds of motion-compensated deinterlacing

The terms ‘proscan up-conversion’ or ‘deinterlacing’ stand for algorithms for the conversion of interlaced image sequences into progressive format by interpolating the lines which are missing due to interlaced scanning. Although deinterlacing is already known to improve TV image quality, such techniques will become even more important in future. Firstly, standard interlaced image sequences will be increasingly processed and displayed on computer platforms and thus usually require progressive scanning and an increased temporal resolution. Secondly, the emerging market of light valve projection equipment demands high-quality proscan up-conversion since the image quality of these display techniques relies heavily on the light efficiency of non-interlaced scanning. By describing deinterlacing as a problem of linear prediction theory, this paper derives upper MSE performance bounds for these algorithms. Thus, a theoretical framework is provided which allows to analyse the effects of various parameters like motion vector inaccuracy, temporal integration and memory constraints on the efficiency of motion-compensated deinterlacing. It is, for example, shown that these algorithms can be very sensitive to motion vector inaccuracies especially if the image sequence is recorded with very short exposure time. Finally, it is briefly demonstrated that the presented analysis can easily be extended to the case of field- and frame-rate up-conversion of interlaced (‘100 Hz’) and non-interlaced image sequences.     

Investigation of fluoacid based conversion coatings on aluminum

Conversion coatings on metals enhance paint or lacquer adhesion and promote corrosion resistance. Traditionally, these conversion coatings were based on chromium chemistry. In recent years, formulations based on fluotitanic or fluozirconic acid and polymer have demonstrated performance on a par with chromium-based treatments. The choice of fluoacid and polymer in the treatment has a strong impact on coating performance. The impact of pretreatment composition was demonstrated for aluminum extrusion processes. Electrochemical investigation, including linear polarization and electrochemical impedance spectroscopy, was used to differentiate corrosion resistance among the various treatments. Scanning electron microscopy, grazing angle infrared spectroscopy, and X-ray photoelectron spectroscopy were used to elucidate chemical composition of the treated aluminum surfaces.     

兰州石化50万t/a催化轻汽油醚化装置运行与优化

采用中国石油自主研发开发的催化轻汽油醚化工艺(LNE)技术,兰州石化建成50万t/a轻汽油醚化装置并投产成功。装置数据表明,C5、C6叔碳烯烃转化率分别为72%~77%、50%~60%,催化轻汽油烯烃减少量为18.0个百分点以上,醚化产品油中总醚化物含量为46%~60%,醚化产品油辛烷值(RON)为98~100,目前该装置已不间断平稳运行1年以上。醚化装置运行效果良好,产生了显著的经济效益和社会效益。     

Optimization of the dye-sensitized solar cell performance by mechanical compression

In this study, the P25 titanium dioxide (TiO₂) nanoparticle (NP) thin film was coated on the fluorine-doped tin oxide (FTO) glass substrate by a doctor blade method. The film then compressed mechanically to be the photoanode of dye-sensitized solar cells (DSSCs). Various compression pressures on TiO₂ NP film were tested to optimize the performance of DSSCs. The mechanical compression reduces TiO₂ inter-particle distance improving the electron transport efficiency. The UV–vis spectrophotometer and electrochemical impedance spectroscopy (EIS) were employed to quantify the light-harvesting efficiency and the charge transport impedance at various interfaces in DSSC, respectively. The incident photon-to-current conversion efficiency was also monitored. The results show that when the DSSC fabricated by the TiO₂ NP thin film compressed at pressure of 279 kg/cm², the minimum resistance of 9.38 Ω at dye/TiO₂ NP/electrolyte interfaces, the maximum short-circuit photocurrent density of 15.11 mA/cm², and the photoelectric conversion efficiency of 5.94% were observed. Compared to the DSSC fabricated by the non-compression of TiO₂ NP thin film, the overall conversion efficiency is improved over 19.5%. The study proves that under suitable compression pressure the performance of DSSC can be optimized.     

基于UG软件的五轴数控加工后置处理研究

从分析刀轨文件和NC代码的格式入手,找出指令的一一对应关系,弄清诸多从建模到加工过程中的坐标系统,建立5坐标铣削中心坐标转换数学模型,从而实现从刀轨文件提取信息转化为NC代码的算法.最后通过实例验证了该加工中心后置处理技术的正确性.     

基于Master CAM的数控代码转换系统开发及应用

MasterCAM内部虽然带有许多后置处理程序,但并不能直接应用于一些在我国使用比较普遍的数控系统。针对这一状况,在分析了Master CAM后置处理程序特点的基础上,构思系统的开发流程,利用VB 6.0程序开发环境进行相应的界面设计和程序开发,开发出了一个小型软件系统,可使Master CAM生成的后置处理程序直接转换为多种数控系统所需的NC代码,从而满足不同数控系统的需求。并以实际应用验证系统运行的实用性和可靠性,以及操作的简便性。