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991.
结合系统仿真技术、实时监控技术、数据库技术和可视化技术,开展碾压混凝土坝仓面施工仿真可视化分析研究,构建仓面施工精细仿真模型。该模型不仅可以通过仿真计算获得详细的仓面施工进度信息,而且实现了可交互的仓面施工三维动态可视化分析。研究成果已应用于西南某碾压混凝土坝工程。 相似文献
992.
In this paper, the hot compressive deformation characteristics of a Mg–10Gd–3Y–0.5Zr(GW103K) alloy have been investigated by isothermal compression test at the temperature range of 350–450°C and strain rate range of 0.0001–0.1s~(-1). True stress–strain relationships at various strain rates showed the typical strain hardening and softening stage which is indicative of dynamic recrystallization during deformation. The results showed that the peak stress was obviously dependent on temperature and strain rate. A constitutive equation to describe the deformation process was established based on the hyperbolic sine function. The stress exponent n and apparent activation energy Q were determined to be 3.018 and 203.947 k J/mol, respectively. Microstructure investigation showed that dislocation slipping was the dominant deformation mechanism during the hot deformation at all conditions. However, at the temperatures lower than 400 °C and strain rates higher than 0.01 s~(-1), twinning was observed to be activated, which indicated another deformation mechanism. Dynamic recrystallization and dynamic precipitation were found to occur simultaneously under such deformation condition. 相似文献
993.
994.
高频焊管生产环境复杂,测温环境恶劣,针对此特点,提出使用比色测温法进行高频焊管的温度测量,并介绍高频焊管测温系统的构建过程.红外测温仪具有较强的抗干扰能力和稳定性,实验选用红外测温仪作为传感器构建温度采集监测系统硬件平台;选用LabVIEW软件构建温度采集监测系统软件平台,其具有采集效率和测试精度高,模块小,编程简单等优点.实验证明,基于LabVIEW平台设计的高频焊管红外测温系统能准确测量到高频焊管焊接温度,并且在LabVIEW模块上实现信号的实时显示、存储和分析. 相似文献
995.
An alteration in stress/strain distribution within periodontal ligament (PDL) occurs when the tooth is mechanical stimulated in orthodontic treatment. The majority of previous finite element studies were confined to a static evaluation on initial loading status, and a dynamic long-term analysis was rarely performed in orthodontics. The present study sought to analyze the stress distribution patterns within tooth root, PDL, and alveolar bone during dynamic canine tipping and bodily movement with three-dimensional finite element method in four consecutive therapeutic weeks. We observed that the highest stress was on root surface, secondly alveolar bone, and finally, PDL for either tipping or bodily movement. Throughout the PDL and root surface, the highest stress was always around the cervical area in both patterns of movement through four phases. Moreover, a lower and more uniform stress distribution was produced during bodily movement compared with tipping movement. These results indicated that canine translation might be healthier for periodontal tissue than tipping movement; the cervical region bore a greater load and might also be a susceptible area for tissue damage (except for the apex) regardless of movement pattern. 相似文献
996.
南丁 《内蒙古民族大学学报(自然科学版)》2013,(6):648-650
近年来,交互式电子白板作为一种新兴教学工具,在我国基础教育及高等教育中的应用越来越普遍。本文首先对交互式电子白板的定义及其在教学上的优势进行阐述,并进一步对我国交互式电子白板的研究应用现状进行梳理,以期发现和总结我国交互式电子白板研究特点,并对今后交互式电子白板的应用及研究提供一些思考和启示。 相似文献
997.
Xu HuiPing Zhang YanWei Xu ChangWei Li JianRu Liu Ding Qin RuFu Luo ShenQian Fan DaiDu 《科学通报(英文版)》2011,56(26):2839-2845
The seafloor observation system is becoming an important infrastructure for marine research because it is transforming oceanic research from temporal investigation to long term observation.The East China Sea coastal seafloor observatory,located between 30°31′44″N,122°15′12″E and 30°31′34″N,122°14′40″E,is constructed near the Xiaoqushan Island outside the Hangzhou Bay on the inner continental shelf of the East China Sea.The observatory is connected by a submarine optical fiber composite power cable that is more than one kilometer long and consists of a special junction box that transmits power and communication signals to different instruments.The special junction box has a variety of waterproof plugs and connects to three different instruments installed in a trawl preventer.The submarine optical fiber composite power cable is landed on the platform by The East China Sea Branch,State Oceanic Administration and the power is continuously supplied by the solar panels and solar battery on the top of the platform.The real time data are directly sent through the cable to the platform and are transmitted by CDMA wireless to the receiver at the State Key Laboratory of Marine Geology of Tongji University.Measurements at the observatory have been taken since April 20,2009 after installation and the results have been interpreted.The characteristics of the near bottom boundary are constrained by a sediment suspension model using portion of the observed data.In particular,discussion is provided on the sea surface height anomaly at Xiaoqushan Island influenced by the tsunami driven by the 2010 Earthquake in Chile.The successful establishment of the coastal seafloor observatory is the first step toward future development of seafloor observation systems in China.It not only accumulates experiences in technology and engineering,but also paves the way for performing important oceanic research using the long term continuous observation platform. 相似文献
998.
通过运用文献资料、逻辑分析等方法,分析探讨了现阶段武术散打运动在高校发展面临的问题,并对武术散打运动在高校可持续发展提出了一些可行性建议。 相似文献
999.
墨子的义利观对"义"和"利"做了本质规定,提出了义利关系的一般原则,并给予了其实施的经济、政治、伦理方面的保证.其义利伦理思想有一定的局限性,但在今天仍然有重要的现实意义. 相似文献
1000.
丁武军 《江西科技师范学院学报》2001,(2):97-100
高职旅游专业设置与课程体系的构建是培养21世纪旅游业所需求应用技术型人才开基础,文章对高职旅游的专业培养目标调整,专业设置调整,课程体系调整,专业师资队伍构建提出若干建设性意见。 相似文献