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991.
992.
围绕仓储网络监控系统设计与开发工作进行研究和实践。利用先进的Lonworks现场总线、LNS网络操作系统和新型数字式传感器DS1820等实现了系统硬件结构的优化及软件方案的设计。详细介绍了基于Lonworks总线协议的仓储网络监控系统的整体结构、硬件设计、系统通信网络方案以及系统软件的开发和具体实现。系统可以通过智能通信接口或标准的通信网络协议和功能监控系统组成更加完善的现化仓储自动化网络管理系统。 相似文献
993.
The essential switching frequency response characteristics of a low cost wireless power driving and controlling system for electrically tunable liquid crystal microlenses (ETLCMs) are obtained. The wireless power system is mainly composed of two coils with different radius and winding as well as a power metal-oxide-semiconductor field effect transistor switch. The voltage response in the small coil, which is connected directly with ETLCMs, is measured and analyzed under the condition of changing some key parameters of the coil system, such as the width of switching frequency region and the duty-cycle of the switching signal ranging from 20% to 80% in intervals of 20%. Through extending the switching frequency range to a few hundreds of kilohertz, an attractive property of only modulating switching frequency to tune precisely the rms voltage in the small coil for ETLCMs is presented. Some interesting phenomena in high frequency regions, for instance, the rms voltage being stable or slightly changed as the frequency, the voltage response cutoff or disappearance after the frequency surpassing a threshold value, and then regeneration after lowering the frequency to lower frequency point than that of generating voltage response cutoff during increasing frequency, are also discovered. 相似文献
994.
Kan Wang Qinhe Zhang Qingyu Liu Guang Zhu Jianhua Zhang 《The International Journal of Advanced Manufacturing Technology》2017,88(9-12):2589-2602
Various cutter strategies have been developed during milling freeform surface. Proper selection of the cutter path orientation is extremely important in ensuring high productivity rate, meeting the better quality level, and longer tool life. In this work, finish milling of TC17 alloy has been done using carbide ball nose end mill on an incline workpiece angle of 30°. The influence of cutter path orientation was examined, and the cutting forces, tool life, tool wear, and surface integrity were evaluated. The results indicate that horizontal downward orientation produced the highest cutting forces. Vertical downward orientation provided the best tool life with cut lengths 90–380 % longer than for all other orientations. Flank wear and adhesion wear were the primary wear form and wear mechanisms, respectively. The best surface finish was achieved using an upward orientation, in particular, the vertical upward orientation. Compressive residual stresses were detected on all the machined surfaces, and vertical upward orientation provided the minimum surface compressive residual stress. In the aspect of tool wear reduction and improvement of surface integrity, horizontal upward cutter path orientation was a suitable choice, which provided a tool life of 270 m, surface roughness (R a ) of 1.46 μm, and surface compressive residual stress of ?300 MPa. 相似文献
995.
螺旋钻机开采的力学效应及煤柱稳定性研究 总被引:2,自引:0,他引:2
运用数值模拟方法,分析了螺旋钻机开采采场和煤柱的应力分布及塑性区分布特征,研究了煤柱宽度或采场间垂向隔层厚度变化时煤柱的力学效应及破坏机理,为螺旋钻机开采采场和煤柱的设计提供了理论依据。 相似文献
996.
莫洛村位于四川省甘孜州藏族自治州丹巴县梭坡乡境内。距县城5公里,居东经101.55°,北纬30.51°,海拔高度在1900——2000米之间,年平均气温13.6℃,属典型的干旱河谷地带。莫洛村三面环山,西临大渡河,地势由东北向南倾斜,系高山峡谷地貌。村面积20公顷,全村以藏族为主,少量汉族杂居,居民的文化生活水平较低,区内居民以农业为主,相当完整地保持着嘉绒藏民族传统的习俗和居住文化。近年来,丹巴县以其瑰丽的嘉绒藏区文化和素有“千碉之国”美称的古碉建筑群为世人所瞩目。而莫洛村更是以其典型、特有的石砌藏寨建筑和规模宏大、形态各异、建设集… 相似文献
997.
医院的环境设计特点
医院环境具有美学功能。良好的医院医疗环境对患者的康复具有促进作用,优质的医疗环境可以使患者在各种医疗。护理、精神等方面得到舒适的满足,医院的医疗环境是患者医疗过程的第一印象。 相似文献
998.
Yen‐Hung Chen Chi‐Yuan Huang Ming‐Lih Roan Fu‐Der Lai Kan‐Nan Chen Jen‐Taut Yeh 《应用聚合物科学杂志》2010,115(1):570-578
In this study, a copper sulfide layer was instantaneously coated on the polyacrylonitrile (PAN) by an electroless plating method with the reduction agents NaHSO3 and Na2S2O3·5H2O and a chelating agent (ethylenediaminetetraacetic acid, EDTA). A variety of concentrations of EDTA was added to obtain the anchoring effect and chelating effect in the electroless plating bath. The mechanism of the Cux(x = 1, 2)S growth and the electromagnetic interference shielding effectiveness (EMI SE) of the composite were studied. It was found that the vinyl acetate was residual in PAN substrate would be purged due to the swelling effect by EDTA solution. Then, the anchoring effect occurred due to the hydrogen bonding between the pits of PAN substrate and the chelating agent. Consequently, the copper sulfide layer deposited successfully by the electroless plating reacted upon EDTA. The swelling degree (Sd) was proposed and evaluated from the FTIR spectra. The relationship between swelling degree of the PAN composite and EDTA concentration (C) is expressed as follows: Sd = 0.13 + 0.90 × e(?15.15C). On the other hand, the FESEM micrograph showed that the average thickness of copper sulfide increased from 76 to 383 nm when the concentration of EDTA increased from 0.00 to 0.20M. For this reason, the EMI SE of the composites increased from 10–12 dB to 20–23 dB. The GIA‐XRD and laser Raman analysis indicated that the deposited layer consisted of CuS and Cu2S. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
999.
1000.
Liu Ming Guan Mingxiang Wu Zhou Sun Chongwu Zhang Weifeng Wang Mingjiang 《Mobile Networks and Applications》2022,27(4):1593-1603
Mobile Networks and Applications - Motivated by improvement of convergence rate and throughput performance, this work develops a systematic high-speed VLSI implementation of the adaptive filter... 相似文献