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991.
992.
1 Introduction Along with the coming of multimedia society, the needs of the large area display are increasing more rapidly. Laser projection display can acquire fully saturated colors, higher contrast ratio and resolution because of the laser characteristics. Since the first practical acous- to- optic television system was developed[1], laser display technology (LDT) has been studied for decades. But the argon- ion lasers used in earlier laser projection dis- play were charecterized by inef… 相似文献
993.
This study investigates the closed-loop measurement error in computer numerical controlled (CNC) milling as they relate to the different inspection techniques. The on-line inspection of machining accuracy using a spindle probe has an inherent shortcoming because the same machine-produced parts are used for inspection. In order to use the spindle probe measurement as a means of correcting deviations in machining, the magnitude of measurement errors needs to be quantified. The empirical verification was made by conducting three sets of cutting experiments, followed by a design of experiment with three levels and three factors on a state-of-the-art CNC machining center. Three different material types and parameter settings were selected to simulate a diverse cutting condition. During the cutting, the cutting force and spindle vibration sensor signals were collected and a tool wear was recorded using a computer vision system. The bore tolerance was gauged by a spindle probe as well as a coordinate-measuring machine. The difference between the two measurements was defined as a closed-loop measurement error and the subsequent analysis was performed to determine the significant factors affecting the errors. The analysis results showed the potential of improving production efficiency and improved part quality. 相似文献
994.
995.
智能化多通道钢管超声波自动探伤系统的开发与应用 总被引:3,自引:1,他引:3
常少文 《计算机测量与控制》2002,10(6):358-359,365
分析了计算机进行管理的超声波自动探伤系统的检测原理和系统组成以及在焊管生产中的应用状况,该系统统采用智能化探伤技术,实现了在线检测、探头跟踪、闸门设置等功能,肯定了其具有自动化程度高、抗干扰能力强、探伤准确率高及系统稳定可靠等特点。 相似文献
996.
谢宁生 《徐州工程学院学报》2002,(3)
隐性采访是一种非常规的新闻采访活动 ,在发挥舆论监督作用方面起到了公开性采访不可替代的作用。然而隐性采访在法律和道德方面存在着诸多漏洞。目前 ,隐性采访在我国方兴未艾 ,但我们须冷静思考隐性采访“热”的原因 ,看到其中的隐患 ,谨慎操作 ,始终保持清醒的自律意识 ,同时最大限度地争取隐性采访法律和道德方面的生存空间。 相似文献
997.
998.
In the paper the main goals and progress of the surveillance specimen programme for the RPVs WWER-440/213 in Jaslovské Bohunice V-2 and Mochovce NPPs are presented. At Jaslovské Bohunice V-2, the standard surveillance specimen programme (SSSP) was finished and so-called ‘Extended Surveillance Specimen Programme’ (ESSP) was prepared on the base of its critical analysis. For first two units of the Mochovce NPP completely new programmes of irradiation embrittlement monitoring called ‘Modern Surveillance Specimen Programme’ is prepared. It is based on the experience with SSSP and ESSP as well as the recommendations of IAEA experts. This programme will serve for Mochovce NPP during all planned service life. The experience of ESSP application on the 3rd and 4th units in Jaslovské Bohunice V-2 NPP are presented in the paper too. 相似文献
999.
Mefenamic acid is a problematic drug in granulation, tableting, and dissolution due to its poor solubility, hydrophobicity, and tendency to stick to surfaces. In most cases, the specifications of a drug by the pharmacopoeia include identification and purity, but they do not describe the physicochemical drug properties precisely. To characterize the mefenamic acid particle size, surface area measurements, X-ray pattern, differential scanning calorimetry (DSC), wettability, crystal habit, and compression behavior of different batches from two manufacturers were investigated. Due to larger particle size and better wettability, mefenamic acid of Il Yang type was easier to handle in a granulation process. The compression behavior of both types was nearly the same, although particle size, crystal habit, and wettability were very different. 相似文献
1000.
The purpose of this study was to examine the effect of different concentrations of crude pig plasma transglutaminase (TGase) at 0, 0.05, 0.1, 0.2, 0.4 and 1.0% on the quality of low-salt chicken meat-balls. Yield, color, gel strength, microstructure and sensory evaluation were measured. The results showed that both the yield and gel strength of the meat-balls increased as TGase supplement increased (P<0.05) without any obvious effect on color. Scanning electron microscopy (SEM) indicated firmer and more regular gel structures with increasing TGase addition. Texture, juiciness and overall acceptability as judged by sensory evaluation were not statistically affected until the level of TGase reached 1.0% (P<0.05). 相似文献