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991.
The purpose of this study is to conduct a concurrent product and process parameters determination for further cost reduction and quality enhancement. The process design-related parameters, such as process mean, process tolerance and product design-related parameters, such as product tolerance, are considered simultaneously in the proposed approach. To reflect the response from these three key controllable characteristics: process mean, process tolerance and product tolerance, the key measurement score, which is the sum of the mean cost, tolerance cost, quality loss and failure cost, is used to evaluate the present model. Two examples are provided for demonstrating the application of single and multiple quality characteristics. 相似文献
992.
悬浮法合成固体粒状丙烯酸树脂 总被引:1,自引:0,他引:1
研究了悬浮法合成固体丙烯酸树脂颗粒。讨论了不同软硬单体配比对丙烯酸树脂颗粒的玻璃化转变温度、相对分子质量及其分布的影响以及不同的引发剂及悬浮剂对其聚合过程、最终产物形态及上述性能的影响。制得的丙烯酸树脂的数均相对分子质量用凝胶渗透色谱(GPC)测定为3.9×104~6.2×104,相对分子质量分布为2.04~2.32;用红外光谱图表征了制得的丙烯酸树脂结构。差示扫描量热法(DSC)测定了聚合物的玻璃化转变温度(Tg)。 相似文献
993.
Juncong Lin Xing Gao Minghong Liao Jiazhi Xia Guilin Li Ying He 《Computers & Electrical Engineering》2014
Releasing sky lanterns is a popular way of celebrating festivals and ceremonies in the Asian countries. This paper presents a computer-aided approach to help novice users to design flyable sky lantern with desired shape. Given a closed up-right 3D model with a user-specified cutting on the bottom, our system optimizes the shape by regularizing the boundary, smoothing the geometry and improving the volume-to-area ratio to make it feasible for flying. The optimized shape is then approximated by a set of developable patches. Next, through a physical analysis step that tests the flying condition and determines the optimal size, the approximated shape is flattened into 2D patches, which can be printed out and glued together to form the airbag. Finally, the user can attach the airbag to a bamboo frame and assemble the fuel cell. We successfully apply our prototype system to design and construct real sky lanterns. 相似文献
994.
Benedikt Ley Corinna Ogonowski Jan Hess Tim Reichling Lin Wan Volker Wulf 《Behaviour & Information Technology》2014,33(8):815-828
Technological infrastructure at home is changing continuously and is becoming increasingly interconnected. Media devices, including the TV set, provide access to the Internet and offer manifold opportunities to consume media on demand. Additionally, personal devices, such as smartphones, also enable flexible consumption and sharing of media. Questions about how these technologies change the user's media usage and how these changes affect the social structure of a household, however, remain largely unanswered. In order to gain insight into the adoption of new technologies into daily routines, we explored these changes in respect of people's media usage in a qualitative long-term Living Lab study. We will present findings regarding personal routines, flexible integration of new devices into existing practices, influences on households as social systems and related issues in device access and collective use. We will highlight potentials and conflicts regarding device shifts and roles; restrictions in device access; social influences in the living room; and individual changes in media consumption. 相似文献
995.
大开口高承载网格加筋壳的设计与工艺 总被引:1,自引:0,他引:1
本文采用有限元法计算了承受高轴压和外压作用下的大开口复合材料纵横密加筋壳的稳定性,得出不同铺层角度、不同受力工况下的大开口圆柱壳的临界载荷,并采用1:1试验件进行试验验证,将计算值与实验值进行了比较;对大开口复合材料纵横密加筋壳的缠绕工艺进行了研究,解决了大开口网格加筋壳开口补强的一次成型技术和密筋及开口部分的多丝嘴、无增量、非线性机械化缠绕成型工艺技术。 相似文献
996.
In this work, magnesia from natural brucite mineral has been used firstly for catalytic degradation of nitrobenzene and aniline
in presence of ozone. Compared with single ozonation, the catalytic ozonation accelerated markedly the degradation of nitrobenzene
and aniline. The influences of hydroxyl radical scavengers, pH values, and reaction temperatures on degradation were investigated.
It was found that the essential of catalysis was the homogeneous catalysis of hydroxyl ions in water, which accelerated the
generation of hydroxyl radicals. As a catalyst, magnesia from natural brucite has supplied an economical and feasible choice
for catalytic ozonation of nitrobenzene and aniline in industrial wastewater. 相似文献
997.
Additive effects of formaldehyde, propionaldehyde and benzaldehyde on the deposition of tin in acidic solution of tin(II) sulfate have been investigated. The effects of these additives on cathodic polarization and a.c. impedance was measured by galvanostatic or potentiostatic methods, respectively. The reduction products of the aldehyde during the deposition and the diffusion coefficient of Sn(II) in various solutions were also determined. 相似文献
998.
999.
1000.
塑料管材用于干式地板供热、供冷的可行性研究 总被引:4,自引:0,他引:4
据塑料管材的力学性能,针对其应用于地板供热、供冷时应注意的问题,从塑料管材使用条件、管材的选择、管壁厚度的确定、地板结构、介质作用温度及供热、供冷运行方式等方面对塑料管材应用于供热、供冷的可行性进行了探讨,提出了一些相应措施和技术方案,并给出了实例。 相似文献