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141.
基于数据字典的转换工具的设计与实现   总被引:2,自引:0,他引:2  
根据数据通信中原始收发数据的格式,结合树型结构数据字典和模块化设计思想,设计了基于数据字典的转换工具的整体系统框架,将转换工具划分为接口、译码库(.lib)、回调函数和数据字典4个功能模块。在此基础上,使用Qt可视化程序开发软件,完成了基于树型结构数据字典的转换工具C++程序开发。最后,给出了转换工具的UML类图,并详细介绍了程序的工作流程。  相似文献   
142.
Zhu Liang  Li Jie  Zhou Congshu  Gu Yili  Yang Huayue 《半导体学报》2009,30(6):066002-066002-5
For thick resist implant layers, such as a high voltage P well and a deep N well, systematic and uncorrectable overlay residues brought about by the tapered resist profiles were found. It was found that the tapered profile is closely related to the pattern density. Potential solutions of the manufacturing problem include hardening the film solidness or balancing the exposure density. In this paper, instead of focusing on the process change methodology,we intend to solve the issue of the overlay metrology error from the perspective of the overlay mark design. Based on the comparison of the overlay performances between the proposed overlay mark and the original design, it is shown that the optimized overlay mark target achieves better performance in terms of profiles, dynamic precision,tool induced shift (TIS), and residues. Furthermore, five types of overlay marks with dummy bars are studied, and a recommendation for the overlay marks is given.  相似文献   
143.
张涛  杨东明  贺家琳  李海  彭鹏 《电声技术》2009,33(8):75-77,89
介绍了一种支持多标准(MPEG-1,AC-3和AVS)音频码流分析的软件实现方案。基于标准的参考解码器,采用面向对象的编程思想,设计了一种灵活配置的实现结构,不仅能解析出标准中定义的码流信息。根据用户的需求返回解码过程的中间结果,附加波形显示及音频播放等功能,而且方便对其他音频格式进行扩展。首先讨论了码流分析的意义及相关音频标准,然后简介了码流分析工具的架构及具体实现,最后进行了总结和展望。  相似文献   
144.
近年来,为应对低油价形势下的规模效益开发,新疆油田玛湖区块迫切需要进一步增加水平段长度,以提高水平井单井产量。因此,新疆油田在玛湖区块Ma HW1325水平井上开展了2 000 m长水平段的钻井试验。针对该井超长水平段钻井所面临的钻压传递困难、井眼清洁困难、井壁稳定难度大、钻井提速难度大、固井完井难度大等突出问题,通过优化井眼剖面、加装旋转导向工具、优选钻头、采用类油基钻井液体系和韧性水泥浆体系等多项技术对策,有效实现了水平段的顺利延伸和钻井提速目标。Ma HW1325水平井完钻时水平段长达2 000 m,创下了新疆油田水平井钻井水平段长度的新纪录。  相似文献   
145.
A quantitative microbiological risk assessment model was used to quantify the risk of salmonellosis caused by bacterial growth and cross-contamination of chicken meals prepared in households of China. Chinese data on initial loads of Salmonella in chicken carcasses sold at retail, storage time and handling of raw chicken meat in household kitchens and confirmatory transfer rates of Salmonella among different kitchen objects were collected. Only one third of Chinese families in our sample separated the cutting board between raw and ready-to-eat foods. The cross-contamination of ready-to-eat foods from chicken meals via the cutting board, the knife and cooks’ hands increased the frequency of pathogen ingestion and the risk of salmonellosis. A significant decrease in the risk of salmonellosis could be achieved by reducing the cross-contamination when handling raw chicken meat and ready-to-eat foods. Decreasing the prevalence of Salmonella contamination to 8.8% or removing chicken carcasses with contamination densities higher than 100 MPN/100 g at retail was less effective. Using transfer rates of Salmonella from raw chicken meat to the wooden cutting board instead of that from references, a statistically higher risk of salmonellosis per serve due to the cross-contamination in households was observed. The present study validated values of hygiene practices in China to reduce the risk of salmonellosis from contaminated raw chicken meat at retail. Deliberate surveys for cooking behaviors and transfer rates of Salmonella from and to different objects including wooden cutting boards were needed.  相似文献   
146.
针对纳雍W火焰锅炉联箱的特点 ,结合生产中的实际情况 ,介绍了其管座孔加工刀具的设计方法  相似文献   
147.
This work presents a simplified modeling and simulation approach for energy systems engineering that is capable of providing quick and accurate responses during system design. For that, the laws of conservation are combined with available empirical and theoretical correlations to quantify the diverse types of flows that cross the system and produce a simplified tridimensional mathematical model, namely a volume element model (VEM). The physical domain of interest is discretized in space, thus producing a system of algebraic and ODEs with respect to time, whose solution delivers the project variables spatial distribution and dynamic response. In order to illustrate the application of the VEM in energy systems engineering, three example problems are considered: (i) a regenerative heat exchanger; (ii) a power electronic building block (PEBB); and (iii) a notional all‐electric ship. The same mathematical model was used to analyze problems (ii) and (iii), that is, the thermal management of heat‐generating equipment packaging. In the examples, the converged mesh had a total of 20, 2000, and 7725 volume elements. The third problem led to the largest simulation, which for steady‐state cases took between 5 and 10 min of computational time to reach convergence and for the ship dynamic response 50 min (i.e., 80,000 s of real time). The regenerative heat exchanger model demonstrated how VEM allowed for the coexistence of different phases (subsystems) within the same volume element. The thermal management model was adjusted and experimentally validated for the PEBB system, and it was possible to perform a parametric and dynamic analysis of the PEBB and of the notional all‐electric ship. Therefore, because of the observed combination of accuracy and low computational time, it is expected that the model could be used as an efficient tool for design, control, and optimization in energy systems engineering. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
148.
介绍了一种螺旋式熔断器熔芯更换工具,巧妙地利用了杠杆原理,解决了熔芯在熔断时产生的高温使螺纹之间发生膨胀而引起摩擦力增大导致瓷帽旋不下来的问题,从作业步骤、作业时间、危险点控制等方面进行了分析对比,充分显示了使用这一工具的优势。  相似文献   
149.
对机床外防护的选材进行了探讨与分析,通过对机床外防护结构的研究,利用CAE仿真分析软件分析了材料的受力情况,达到合理使用板材的目的,从而使外防护的设计制造更加合理经济。  相似文献   
150.
提出了一种基于自激励的数控机床模态参数提取方法,利用该方法对XHK5140机床进行了实验模态分析,得到该机床的前4阶模态参数,并且将其和计算模态分析结果进行比较,验证了该方法的有效性。解决了传统模态实验设备难以激励大型数控机床的问题。  相似文献   
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