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1.
《Journal of the European Ceramic Society》2022,42(15):7180-7186
In this work, drying of bodies prepared by gelcasting fine submicrometre-sized zirconia particles was studied and a drying process for defect-free bodies with large cross-sections was proposed. It was found that the cracking of large bodies could be prevented by reducing the monomer content and using appropriate non-volatile cosolvents. Glycerol and polyethylene glycols with different molecular weights were used as non-volatile cosolvents in aqueous ceramic suspensions. The complex effects of the individual cosolvents on the gelcasting process and, in particular, on the drying step were investigated and explained. The applicability of individual cosolvents for the gelcasting process were discussed and their optimal use was indicated. 相似文献
2.
Smart grid has opened up a new role of “prosumer” in an energy value network, transforming many conventional energy consumers into prosumers, who not only generate green energy but also share the surplus with utilities and other consumers. The concept of a goal-oriented prosumer community group (PCG) has emerged recently as an effective way to fulfill sustainable energy exchange. Such community-based energy sharing networks comprise multiple irreconcilable objectives such as demand constraints, cost constraints, and income maximization. In many cases, one goal may be achievable only at the expense of other goals. This necessitates the development of an effective framework to manage the multiple goals and reduce the gap with their achievement levels. Therefore, in this research paper, an effective framework is developed to negotiate among the multiple goals and thus to define optimal mutual goals for each PCG in a more sustainable manner using multiple-criteria goal programming techniques. Simulation results are presented to illustrate how the methods work in practical situations, where each of the objective measure is given a target value and the unwanted deviations from this set are minimized in an achievement function. 相似文献
3.
《Construction and Building Materials》2005,19(1):75-79
This paper reports results of a study conducted to investigate the causes of cracks noted on concrete beams in a student facility on a university campus. Cracks were noted on the beams within 6 months of construction. They increased in size within a month. Field and laboratory investigations were conducted to assess the causes of cracking of the beams. The compressive strength of the concrete cores taken from the beams was found to be less than the specified strength. The cracks were repaired by epoxy injection and the structural integrity of the repaired beams was assessed by conducting load tests. The deflection of the repaired beams, under the imposed test loads, was less than that specified by ACI 318 indicating the efficiency of the repair procedure utilized. 相似文献
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提出一种通用的基于视觉传感器的无人系统多模态视觉感知平台的测试与评估的方法,研究了可见光波段和红外光波段下的动态测距实验与复杂光变测距实验. 整个过程采用基于北斗卫星实时授时的时间同步技术和真值采集设备,输出带有时间戳的无人系统多模态感知单元的测量数据和真值数据,并保证了不同设备之间的时间同步误差小于10 ms. 最后,对比测量数据和真值数据,给出测试设备的性能与功能的量化评估. 实验结果表明,该测试评估方法有效地获取了真值,并进行了时间同步,满足实际的需求,具备推广性. 相似文献
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为探究微波热处理对无托槽隐形正畸矫治器的力学性能影响,对立体光固化(SLA)打印的标准试样件在不同功率的微波热处理后进行拉伸、弯曲力学性能测试,并通过3D偏差验证矫治器压膜工序前添加微波热处理工艺的有效性。结果表明,微波功率为400 W时,拉伸强度为50.6 MPa,提升了19.06%,断裂伸长率达到13.24%,弯曲强度为66.8 MPa,弯曲模量为2042 MPa;经过微波热处理的牙模压膜后在0.1 mm公差范围内的变形率降低了14.33%。微波热处理能够优化树脂制件的力学性能,并有效提高矫治器的制造精度。 相似文献
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近年来,北京市垃圾渣土管理处逐步建设和运行了垃圾处理设施、在线监测计量、市容环境监督检查、建筑垃圾管理、环卫信息和其他业务信息化等应用系统,这些业务系统部署在42台服务器等硬件设备上。服务器作为承载信息系统的基础,保证服务器的良好运行,从而提高信息系统的稳定性,是机房运维管理人员需要研究的课题。结合工作实际,讲解本单位服务器的运维管理。 相似文献
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The corrosion of materials in combustion chamber of yellow phosphor tall gas was investrgated. The results reveal that the corrosion behavior is different for different materials under actual work conditions. 相似文献
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随着移动终端的不断发展与普及,它已经变成了一个交流、传感的设备。普通市民只需要通过移动设备就可以从周围的环境中获取海量信息以及分享自己的信息。文中研究了群智感知原理,结合普适环境下情境信息的特点,提出了移动终端智能引擎平台。该平台通过接口能实时、有效地获取、处理用户的感知数据,还原用户情境,获取用户需求,并把用户需求和处理好的数据供第三方应用使用,第三方应用通过平台提供的接口提供应用服务。实验证明,该平台能够有效地获取用户情境信息,提供给第三方应用。 相似文献