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针对萧甬线K78+600基床下沉外挤病害情况,对基床土进行了填料试验和强度检测,分析了产生病害的原因,并采用土工格室结合土工膜封闭的整治措施,从动应力的角度对换填厚度进行了计算分析。 相似文献
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Oblective To observe the effect of bile reflux on the intragastric pH. Methods We used ambulatory intragastric pH monitoring along with simultaneous Bilitec 2000 to measure the pH and absorbance of the mixed gastric juice diluted with bile with increasing bilirubin concentration in vitro and the yellow and clear gastric juice aspirated under endoscopy. In vivo,we studied 20 functional dispepsia patients for 24 h with simultaneous intragastric pH and bilirubin monitoring. Results In vitro dilutions,the absorbance value reached to 0. 900 while the concentration was only 20% ,but when the pH of the solution was more than 4,it′s concentration was already up to 60%. The mean absorbance of the yellow gastric juice(0. 348± 0. 131) was significantly higher than that of the clear juice (0. 008 ± 0. 003)(P<0.05). The pH of 80% yellow gastric juice was less than 4, the percentage was not significantly different from the clear samples (81%) (P>0. 05). The pH showed no correlation with the absorbance in the yellow and clear groungs. Eight of the 12 patients with the spontaneous nocturnal episcodes of alkalinization had simultaneous increase of absorbance,4 of the 8 subjects with no aikalinization had increase of absorbance. Gonclusion In some concentration,bile reflux affect little on the intragastric pH. 相似文献
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A schedule consisting of an appropriate arrival time at each time control point can ensure reliable transport services. This paper develops a novel time control point strategy coupled with transfer coordination for solving a multi‐objective schedule design problem to improve schedule adherence and reduce intermodal transfer disutility. The problem is formulated using a robust mixed‐integer nonlinear programming model. The mixed‐integer nonlinear programming model is equivalently transformed into a robust mixed‐integer linear programming model, which is then approximated by a deterministic mixed‐integer linear programming model through Monte Carlo simulation. Thus, the optimal scheduled arrival time at each time control point can be precisely obtained using cplex . Numerical experiments based on three bus lines and the mass rapid transit system in Singapore are presented, and the results show that the schedule determined using the developed model is able to provide not only reliable bus service but also a smooth transfer experience for passengers. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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针对某款电动汽车差速器壳体结构的轻量化设计方法展开研究,基于Hypermesh有限元平台建立差速器壳体有限元模型,对其进行静力学分析以及模态分析,证明差速器壳体有足够的优化空间。以优化区域密度为设计变量,最大应力不超过材料屈服强度、一阶固有频率不小于主要激励引起的共振频率为约束,优化区域质量最小为目标,对差速器壳体结构进行拓扑优化。优化后的差速器壳体较优化前质量降低约13.6%,满足强度要求且固有频率较高,实现了差速器壳体的轻量化设计。 相似文献
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通过对汉北河大富水航道工程实施后工程效益、社会综合效益和经济效益进行调查分析,阐明汉北河大富水航道工程的实施达到了预期的目的,投资效果十分显著. 相似文献