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942.
文章针对现有互联网由于原始设计模式方面的不足,难以满足泛在、移动用户的多元化网络服务需求的问题,创造性地提出全新的泛在、移动互联网体系理论与总体框架;创建一种。基础设施层。模型与理论,解决用户在任何地点、任何时间、以任何方式接入到互联网的问题;建立一种。普适服务层”模型与理论,实现对普适服务的支持;并提出新网络体系下的移动性管理机制。新的网络体系结构可克服现有互联网存在的弊端,有效满足泛在、移动方面的多元化网络服务需求。 相似文献
943.
A chemical detector ChemPro100i containing aspiration type ion mobility spectrometry (aspiration IMS), five semiconductor sensors (MOS) and field effect transistor sensor (FET) was used for the detection and monitoring of microbial volatile organic compounds (MVOC). MVOCs were detected from the headspace of glass chambers which contained a specimen of building material in humid conditions. Results regarding particle board as a substrate for mould growth are represented. A specimen kept under sterile conditions was used as a reference. Samples were incubated for 22 days and detector responses as well as air samples introduced into Tenax adsorbent were collected for seven days during the incubation. Air samples were analyzed by thermal desorption gas chromatography mass spectrometry (TD-GC-MS) for identifying the possible MVOCs. MVOC detection was done by comparing the chromatogram peak intensities between the contaminated and the sterile samples. Detector responses were monitored before and after air sampling and data was analyzed by means of multivariate data analysis (MVDA) using SIMCA-P 10.0 software (Umetrics, Umeå, Sweden). Results showed that when incubation proceeded the different samples could be separated by both aspiration IMS combined with sensors and TD-GC-MS and that the results obtained by both methods also had a visible time trend. 相似文献
944.
Experimental investigation and model improvement on the atomization performance of single-hole Y-jet nozzle with high liquid flow rate 总被引:2,自引:0,他引:2
Y-jet nozzle, as an efficient multi-hole internal-mixing twin-fluid atomizer, has been widely used for liquid fuel spray in many industrial processes. However, single-hole Y-jet nozzle with high liquid flow rate is indispensable in some confined situations due to a small spray cone angle. In this paper, the atomization performance of single-hole Y-jet nozzles with high liquid mass flow rates ranging from 400 to 1500 kg/h for practical semidry flue gas desulfurization processes was investigated by the laser particle size analyzer, and the effects of spray water pressure, atomizing air pressure and air to liquid mass flow ratio on the liquid mass flow rate and the droplet size distribution were analyzed. Moreover, the secondary atomization model was modified on the basis of previous random atomization model of Y-jet nozzle. The predicted results agreed well with the experimental ones, and the improved atomization model of Y-jet nozzle was well validated to design the nozzle geometry and to predict the droplet size distributions for single-hole Y-jet nozzle with high liquid mass flow rate. 相似文献
945.
946.
The structure of organic thin film transistors (OTFTs) is optimized by introducing floating gate into the gate dielectric to reduce the threshold voltage of OTFTs in this article. Then the optimized device is simulated and the results of the simulation show the threshold voltage of optimized device is reduced by about 10 V. The reduction of the threshold voltage is helpful and useful for the application of OTFTs in many areas. In addition, this way to reduce threshold voltage of OTFT is compatible with traditional silicon technology and can be used in manufacture. 相似文献
947.
大尺寸开洞结构的简化平面应变模型的分析和探讨 总被引:2,自引:0,他引:2
在轨道交通建设中,结构设计方案常涉及到大尺寸开洞结构的受力问题,如盾构施工竖井、轨排工作井等。本文以轨排井为例,采取合理的假设条件,将轨排井洞口纵梁的弯曲刚度转化为该点处的等效弹性支点刚度,建立简化的平面应变模型,进行结构受力分析和结构设计。通过与空间板壳模型进行对比分析,表明此类大尺寸开洞结构的简化平面应变模型是合理可行的,为类似工程设计提供了一定的参考和依据。 相似文献
948.
949.
This study examined imprint lithography with a two-step Ni stamp to solve the laser process problems and simultaneously form a blind via and layer pattern. The Ni stamp was fabricated by electroplating on a dry-etched Si mold, made from a SOI (silicon on insulator) wafer, and pattern replication. For the pattern transfer of the Ni stamp, hot embossing was performed on SU8-coated BT and Si wafer substrates. The residual layer was of a uniform thickness with an embossed shape of acceptable squareness. 相似文献
950.
基于沈阳城区挖孔桩竖向承载力试计比的统计参数和无量纲随机变量的极限状态方程,对挖孔桩竖向承载力进行了可靠性分析;采用校准法计算了沈阳地区地基规范中挖孔桩的目标可靠指标,并分析了荷载效应比、荷载组合和抗力概型分布对可靠指标的影响。研究结果表明,挖孔桩竖向承载力标准值遵循对数正态分布,荷载效应比和荷载组合形式对可靠指标的影响较大,抗力概型分布对可靠指标有一定程度的影响,挖孔桩竖向承载力在不同的荷载组合下应采用不同的目标可靠指标。 相似文献