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41.
作为一种文学意象,“夜”经常出现在陈毅诗词中。在陈毅诗词中,由于创作时代背景和诗人创作心理,“夜”不仅是时空概念,更赋予了紧张战斗、自由思想、欢乐工作的丰富内涵,具有独特的表现特征和审美价值。通过对陈毅诗词夜意象的探析,可以探究陈毅诗词的艺术价值。 相似文献
42.
J. H. Li P. Deshpande R. Y. Lin 《Journal of Materials Engineering and Performance》2004,13(4):445-450
The objective of this study is to investigate an innovative infrared (IR) technique to enhance adhesion of electroplated copper
(Cu) on Ti-6Al-4V without dichromate dipping. The ultimate goal is to develop a Cu coating process on Ti-6Al-4V without hazardous
hexavalent chromium (Cr) solution treatments. Cu coatings of around 50 μm were electroplated on Ti-6Al-4V specimens at a current
density of 0.03 A/cm2 in an acidic Cu solution. To improve adhesion of coatings, IR heat treatments were performed on the Cu-coated samples at
different temperatures and durations: 860 °C for 600 s and 875 °C for 20–120 s. This process was accomplished in an attempt
to replace the use of dichromate dipping before electroplating. For samples heat treated at 860 °C, no bonding existed, even
after 600 s. It is believed that solid-state diffusion prevailed at 860 °C and that 600 s was not enough for sufficient diffusion
to occur. Adhesion was poor when samples were heat treated at 875 °C for 20 s. Excellent adhesion was observed when the heat
treatment holding time was increased to 40 s. For 90 s, the surface appearance of coatings partially changed from Cu-colored
to a grayish color. There was no Cu left on the surface after a 120 s heat treatment. From optical microscopic observations
on sample cross sections, an interlayer between the Cu and Ti-6Al-4V formed when heat treated at 875 °C for 40 s and longer.
The interlayer thickness increased as the holding time increased, until depletion of Cu. The sheet resistivity of coated specimens
was on the order of pure Cu for samples heat treated at 875 °C and less than 90 s. During the 875 °C heat treatment, the following
occurred: solid-state diffusion of Cu in Ti-6Al-4V, formation of eutectic solutions, dissolution of Cu and Ti-6Al-4V into
the liquid phase, and the formation of intermetallic compounds. The lowest eutectic temperature of 875 °C played a key role
in this innovative process of Cu coating on Ti-6Al-4V.
This paper was presented at the 2nd International Surface Engineering Congress sponsored by ASM International, on September
15–17, 2003, in Indianapolis, Indiana and appears on pp. 403–10 of the Proceedings. 相似文献
43.
S. Fedosov Samara State Technical University Galaktionovskaya Samara Russia 《金属学报(英文版)》2000,13(2):557-560
1.IntroductionTheoneofthemostimportantparametersofthethermalcycleduringsurfacepulseheatingistherateofheatingandcooling.Knowledgeofthesevaluesinparticulartemperatureintervalshelpstoprognosticatephasestructureintheheataffectedzones(HAZ),toanalyzecausesofthestructuretransformations.Todaythereisavoluminousliteratureoncalculationofthethermalconditionsforasolidduringsurfaceprocessing.Butthetemperaturevariationsareusuallyexaminedasafunctionoftimeorspacecoordinates.Sometimesthefirstderivativeofthete… 相似文献
44.
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46.
Naoji Shiroma Ryo Miyauchi Akira Nagafusa Youhei Haga Fumitoshi Matsuno 《Advanced Robotics》2015,29(3):149-163
In robot teleoperation, a robot works as a physical agent at a remote site for a robot operator. There are mainly two tasks in robot teleoperation using camera images: environment recognition using visual information and robot control according to the recognition. In this paper, we propose a gaze direction based vehicle teleoperation method with an omnidirectional image stabilization and an automatic body rotation control. In the proposed method, we manage above two tasks in the same manner that are usually treated separately. This method is an intuitive vehicle teleoperation method where an operator do not need to have concern about vehicle body orientations and can absorb differences of vehicle driving mechanisms. That is, this method frees an operator from being bothered from controlling a vehicle and the operator can concentrate on where he/she intends to go. This method mainly consists of two technologies: an omnidirectional image stabilization technology and automatic body rotation control. The conducted experiments show effectiveness of the proposed method. 相似文献
47.
48.
分组加工模式的应用是特色工艺研究和精细化加工的结合,目前被应用在了很多企业中。为了解决计划制订到生产调度指挥这一过程中的问题,企业采用了MES技术来优化这一模式下的工艺过程。分析了MES技术的应用。 相似文献
49.
《国际互联网参考资料服务季刊》2013,18(2):75-96
Multi-user Data base (MUD) technology, and its object-oriented descendant (MOO), is one of the most exciting tools to surface on the Internet, and offers libraries and librarians a unique opportunity to participate in creating user-friendly standardized interfaces to many of our most frequently used resources. These resources include those we access through the Internet already, using gopher, telnet, WWW, and FTP, and also those proprietary databases that we currently access through leased lines such as OCLC First Search, Prism, DIALOG, and many others. MOO technology is already being used successfully to create user-extensible collaborative professional environments for educators, astronomers, and computer network systems administrators. With the growing relevance of the Internet for libraries and other information professionals, it behooves the library community to engage those emerging technologies which will aloow us to interface most effectively with the Internet and its many resources, with the proprietary databases which we depend on, and with one another. 相似文献
50.
针对工程中常用的混凝土材料的不均匀特性,提出了一种基于图像处理技术建立二维混凝土有限元模型的方法.该方法综合图像处理过程中的图像增强、消除噪声和边缘检测技术建立人机对话平台,并结合网格自动划分技术建立非均匀有限元模型.通过一个实例,验证了该方法的有效性. 相似文献