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91.
92.
This paper presents the design optimization process of a short fiber-reinforced plastic armrest frame to minimize its weight
by replacing the steel frame with a plastic frame. The analysis was carried out with the equivalent mechanical model and design
of experiment (DOE) method. Instead of considering the whole structure, it is divided into three simpler regions to reduce
the complexity of the problem through examining its structural characteristics and load conditions. The maximum stress and
deflection of the regions that carry the normal load are calculated by the analytical mathematical form derived from an equivalent
model. The other regions loaded by contact stress are handled by FEM (finite element method), the DOE method, and the RSM
(response surface model). To optimize the design variables in both cases, the object functions derived from these calculations
are solved with a CAE (computer aided engineering) tool. This method clearly shows the mechanical and mathematical representation
of structural optimization and reduces the computing costs. After design optimization, the weight of the optimum plastic-based
armrest frame is reduced by about 18% compared to the initial design of a plastic frame and is decreased by 50% in comparison
with the steel frame. Some prototypical armrest frames were also made by injection molding and tested. The research results
fulfilled all of the design requirements. 相似文献
93.
碾压混凝土在道路建设中的应用及施工技术 总被引:1,自引:0,他引:1
道路碾压混凝土是一种新型筑路材料,有助于缓解当前我国建设需求与建设资金、资源等的矛盾.通过分析典型工程实例,探讨碾压混凝土在道路面层、基层、路基工程中的应用,并论述道路碾压混凝土施工技术的新进展. 相似文献
94.
Objective To study the expression of interleukin-2 (IL-2), soluble interleukin-2 receptor (sIL-2R), determine the alteration of erythrocytic immunity and T cell subgroup in the blood of outer circulation in patients with hypertensive cerebral hemorrhage so and to probe into the relationship between them, and to explore the clinical significance. Methods Enzyme linked immnunosorbent assay (ELISA) was used to determine the content of IL-2 and slL-2R. The immunoadsorption was employed to examine the erythrocytic immune activity and its regulating function. ( S-P) was used to determine the cell number of CD3 (cluster of differentiation3), CD4 and CD8. Resolts The content of IL-2 in the group with hypertensive cerebral hemorrhage was significantly lower than that in the control group (P〈0.01), and the content of sIL-2R increased. Red blood cell C3b receptor (RBC. C3bR) and RBC immune adherence enhancing factor (RFEB) dropped greatly (P〈0.01), while RBC immune complex rosette (RBC. ICR) and RBC immune adherence inhibiting factor (RFIR) increased greatly. The cell number of CD3 and CD4decreased (P〈0.01) and there was no obvious change in CD8 (P〈 0. 05). Conclusion The decrease of immune function was observed in patients with hypertensive cerebral hemorrhage. The determination of the content of IL-2, sIL- 2R, erythrocytic immunity and the activity of T subgroup has an important clinical significance in the occurrence, development, treatment, and prognosis of hypertensive cerebral hemorrhage. 相似文献
95.
96.
以1.6~2.5 mm的新疆核桃壳作为吸附剂,研究其对模拟废水中Pb2+和Ni2+的吸附性能。实验表明:25℃,pH值为5.5,吸附剂用量1.2 g时Pb2+的吸附量最大;pH值为6.0,吸附剂用量2.0 g时Ni2+的吸附量最大,Pb2+的吸附容量为Ni2+的3倍。Pb2+, Ni2+竞争及偏好吸附表明,Ni2+的干扰使Pb2+的吸附容量下降14.8%,Pb2+的干扰使Ni2+的吸附容量下降66.5%,吸附剂对Pb2+的选择性更高。 相似文献
97.
介绍在宋家庄车站顶板设置铺轨基地的起因、建设经历,阐述该基地的实施效果即有力地保证北京地铁5号线总工期,证明施工过程中良好的适应性和应变能力的必要性和重要性。 相似文献
98.
分析经MRI确诊的糖尿病腔隙梗塞37例,探讨糖尿病与腔隙梗塞的关系。认为腔隙梗塞是糖尿病的一种特征性改变,是其临床表现之一,应称为糖尿病腔隙梗塞。本组资料表明,糖尿病腔隙梗塞病灶为多发,见于大脑中动脉支配之皮层下部位和桥脑、小脑等,临床表现与非糖尿病腔隙梗塞无特异性差别。 相似文献
99.
本文通过宏微观结合,研究了奥氏体不锈铜常温及低温下低循环变形行为,着重讨论了应变幅值、试验温度、奥氏体稳定性对低周疲劳寿命、循环硬化/软化的影响;分析宏微观试验结果,提出了材料循环变形过程中硬化与软化同时存在的观点。 相似文献
100.
对38例单纯先天性肾积水肾盂输尿管连接部(UPJ)组织作透射电镜观察,结果:其主要超微结构病理改变是平滑肌细胞间有大量胶原料堆组织堆积,平滑肌细胞相互分离,肌细胞本身发育不良,胞膜皱折、锯齿状、指状突起,线粒体肿胀破坏。提示积水的原因是UPJ部位功能性梗阻。 相似文献