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1.
介绍了粉末注射成型技术的概念和工艺,包括金属粉末注射成型(MIM)、陶瓷粉末注射成型(CIM),讲述了黏结剂的使用发展情况;阐述了粉末注射成型专用注射成型机的特点,PIM粉末注射专用塑化系统,PIM专用料斗滑块装置,镶套式机筒座等,介绍了PIM技术在诸多行业中的应用,3C行业,医疗行业,汽车行业等,并展望了PIM研究的发展方向。  相似文献   
2.
Wastewater containing volatile organic compounds (VOCs) is generated in various industrial processes and is seriously harmful to the natural environment and human health. Its treatment has become extremely important due to increasing environment concerns. Here, a high permeable membrane for fast and high‐efficient VOCs removal from aqueous solutions by pervaporation is reported. The as‐prepared PIM‐1 membrane allows ultrafast permeation of VOCs and exhibits excellent VOCs selectivity, particularly for ethyl acetate, dimethyl ether, and acetonitrile. Typically, the PIM‐1 membrane exhibits an ultrahigh flux and separation factor of 39.5 kg μm m?2 h?1 and 189, respectively, in the pervaporation of 1.0 mol% aqueous ethyl acetate solution. Furthermore, the solubility‐diffusion mechanism is revealed in the pervaporation of 10 kinds of 1.0 mol% VOCs solutions. It is found that the pervaporation performance is affected directly by physicochemical properties of VOCs. Moreover, effects of feed composition and temperature on the pervaporation are studied in details. © 2015 American Institute of Chemical Engineers AIChE J, 62: 842–851, 2016  相似文献   
3.
近几年,随着软件开发技术的发展,软件开发的步骤越来越规范化,开发的规范化固然便于软件的管理和日后的维护,但是这同时也带来一个不可避免的问题:开发人员编写重复代码工作量的骤然提升,一个很好的实例是基于SSH(Struts2,Spring,Hibernate)框架的开发。本文采用MDA(Model Driven Architecture)技术结合SSH开发框架提出一种新的代码生成方案sMDA,sMDA很好地解决重复代码编写的问题。相比于以往复制粘贴的编码模式,sMDA会自动生成系统的关键代码。  相似文献   
4.
结合国家和建筑行业相关统计数据,并综合有关研究成果确定关键指标,采用永续盘存法对我国建筑业1980~2009年的资本存量进行测算,同时对分行业资本存量进行比较分析。结果表明我国建筑业资本存量总体呈逐年上升趋势,房屋建筑业和铁路、公路、隧道、桥梁行业的增长速度要明显高于其他行业。  相似文献   
5.
分析目前电网继电保护状态评价与辅助决策系统的现状,指出缺乏统一建模是相关系统在架构上的主要缺陷,提出根据模型驱动体系结构的核心思想,建立继电保护状态评价与辅助决策全过程的平台无关信息模型(PIM)。首先对继电保护状态评价与辅助决策的全过程进行抽象总结,然后通过对状态量采集和存储、状态评价和辅助决策这3个过程分别进行分析和建模,最终给出继电保护在线状态评价与辅助决策系统PIM模型的参考架构。  相似文献   
6.
IPTV broadcast channels and video content distribution are increasingly saturating network paths. New solutions based on inter‐domain multicast protocols could contribute to the enhancement of multimedia content distribution over the Internet. The aim of this paper is to propose new capabilities for an existing inter‐domain multicast protocol, the Protocol Independent Multicast‐Sparse Mode. We describe the modified protocol and analyze its behavior using newly developed tools based on an open‐source software simulator. The resulting protocol does not require topology information, which is advantageous for easier deployment. In addition, the adopted solution avoids inherent problems with inter‐domain multicast routing, such as multiple paths and path asymmetries.  相似文献   
7.
Tb achieve the purpose of applying design patterns which are various in kind and constant in changing in MDA from idea and application,one way is used to solve the problem of pattern disappearance which occurs at the process of pattern instantiation,to guarantee the independenceJpatterns,and at the same time,to apply this process to miltiple design patterns.Ib solve these two problems,the modeling method of design pattern units based on seta-models is adopted,I.e.,to divide the basic operations into atones in the metamodel tier and then combine the atones to complete design pattern units seta-models without business logic.After one process of conversion,the kxupose of making up various pattern units seta-model and dividing business logic and pattern logic is achieved.  相似文献   
8.
针对传统的风力发电机齿轮箱检修方式存在的不足,引入针对可修系统检修的比例强度模型(proportional intensity model,PIM)概念,提出一种基于故障数据和状态监测数据的风力发电机齿轮箱检修策略。分析了PIM中各参数的意义,并阐述了参数估计算法。利用最小维修成本法确定最优维修决策阈值,绘制最优维修阈值曲线,并制定最优维修策略。通过某型风力发电机齿轮箱的实例分析,验证了此方法在风力发电机齿轮箱维修决策中的应用价值。  相似文献   
9.
none 《粉末冶金学》2013,56(1):34-40
Abstract

Densification behaviours of titanium alloy (Ti–6Al–4V) powder compacts were investigated under uniaxial compression at high temperature. The yield function and a strain hardening law proposed by Kim were implemented into a finite element program (Abaqus) to compare with experimental data of porous titanium alloy powder preforms under PM forging. Experimental data were compared with finite element calculations for the variations of relative density with the applied pressure. Deformed geometry and density distributions of titanium alloy powder compacts under PM forging were also compared with finite element calculations.  相似文献   
10.
Nowadays, more carriers and components are used in cellular networks to satisfy the requirement of high-speed data service. The increase of carriers and components may result in serious problem of passive inter-modulation (PIM). This paper investigates the superposition effect of 3rd-order and 5th-order PIM under multicarrier scenarios with the channelized scheme (CS) and the multiplexed scheme (MS). We use the concept of 'effective hit' and the cumulative inter-modulation factors (CIFs) to evaluate the cumulative PIM product strength on each individual carrier within the receive signal band. Furthermore, with the simulator based on Monte-Carlo method, the group inter-modulation factor (GIF) is calculated to measure the average superposition effect for multiple carriers compared with the benchmark case. The simulation results show that, compared with the CS, the strength of PIM product with the MS does not increases so greatly with the growth of the total number of the carriers. The results are useful for the component designers and the cellular network planners.  相似文献   
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