增龄相关听力丧失小鼠耳蜗毛细胞表型与基因突变的关系

目的　观察增龄相关听力丧失 (AHL)小鼠耳蜗毛细胞病理改变的超微结构 ,为老年性聋病理生理及临床表现+基因表型提供形态学改变依据。方法　应用扫描电镜 (SEM)观察BALB/c小鼠耳蜗Corti器毛细胞的超微结构改变 ,测定动物ABR反应阈值。DNA提取PCR扩增分析基因型。结果　 6月龄BALB/c小鼠耳蜗底回内外毛细胞有连续的缺失 ,静纤毛束有融合、散乱、变短和失去劲度。ABR阈值呈中到重度听力损失。证明种系特异的Ahl基因位点和基因功能。结论　耳蜗毛细胞静纤毛束融合、散乱、变短是老年性聋早期的主要病理改变 ,mdfw与Ah1的表现形式是同一基因位点 ,可能与myosin基因突变有关。     

M10-30门机电气加速控制系统的改造

今年1月3日,我港一台M10-30门座起重机在装卸作业中变幅机构突然自动加速、操纵失控,造成吊装货物将装卸工作打入货池的严重事故.通过现场事故分析 ,失控的原因是变幅机构最后一级加速接触器(3JC4)的吸铁被油污贴牢,在接触器线圈失电的情况下,不能在弹簧的作用下分开,而使主角点闭合.在下次重复操纵时,因加速级 3JC4主接触器的开常触点未能断开,变幅电机转子调速电阻全部被短接,使变幅系统失去由低速到高速的运转过程.     

Research of order allocation model based on cloud and hybrid genetic algorithm under ecommerce environment

For massive order allocation problem of the third party logistics (TPL) in ecommerce, this paper proposes a general order allocation model based on cloud architecture and hybrid genetic algorithm (GA), implementing cloud deployable MapReduce (MR) code to parallelize allocation process, using heuristic rule to fix illegal chromosome during encoding process and adopting mixed integer programming (MIP) as fitness function to guarantee rationality of chromosome fitness. The simulation experiment shows that in mass processing of orders, the model performance in a multi-server cluster environment is remarkable superior to that in stand-alone environment. This model can be directly applied to cloud based logistics information platform (LIP) in near future, implementing fast auto-allocation for massive concurrent orders, with great application value.     

悬臂浇筑施工中连续箱梁预应力管道摩阻测试研究

通过应用最小二乘法原理,由规范中的公式推导预应力管道摩阻系数κ和μ的算式,结合杭州湾跨海大桥北引桥悬臂浇筑施工连续箱梁预应力管道摩阻的现场测试,计算出实际预应力管道摩阻系数,并与设计值和规范值比较,表明管道成孔良好,符合设计要求.     

双壳油船稳性分析

分析了传统型具有两道纵舱壁的单底单壳油船演变为双底双壳油船后,发生稳性不足的原因.阐述了MARPOL条款25A和统一解释UI11A对油船稳性的要求,并指出其中存在的不妥之处.叙述了作为UI11A变通等效的IACS(WP/SSLL)40次会议UIMPC决议案的内容,提出了一套执行该决议案的具体核算方法.     

嵌入式系统在单元制动器试验台上的应用

介绍了嵌入式系统的特点及在单元制动器试验台控制系统中的的应用.     

A macro model for traffic flow on road networks with varying road conditions

In this paper, we develop a macro traffic flow model with consideration of varying road conditions. Our analytical and numerical results illustrate that good road condition can enhance the speed and flow of uniform traffic flow whereas bad road condition will reduce the speed and flow. The numerical results also show that good road condition can smooth shock wave and improve the stability of traffic flow whereas bad road condition will lead to steeper shock wave and reduce the stability of traffic flow. Our results are also qualitatively accordant with empirical results, which implies that the proposed model can qualitatively describe the effects of road conditions on traffic flow. These results can guide traffic engineers to improve the road quality in traffic engineering. Copyright © 2012 John Wiley & Sons, Ltd.     

A new algorithm to automatically extract the drainage networks and catchments based on triangulation irregular network digital elevation model

A new algorithm to automatically extract drainage networks and catchments based on triangula- tion irregular networks （TINs） digital elevation model （DEM） was developed. The flow direction in this approach is determined by computing the spatial gradient of triangle and triangle edges. Outflow edge was defined by comparing the contribution area that is separated by the steepest descent of the triangle. Local channels were then tracked to build drainage networks. Both triangle edges and facets were considered to con- struct flow path. The algorithm has been tested in the site for Hawaiian Island of Kaho＇olawe, and the results were compared with those calculated by ARCGIS as well as terrain map. The reported algorithm has been proved to be a reliable approach with high efficiency to generate well-connected and coherent drainage networks.     

马来酰化端基聚乙二醇合成工艺的优化

以PEG4000为起始原料,通过对甲苯磺酸酯法生成AT-PEG4000,然后与马来酸酐反应,经过缩合反应合成PEG4000-MAL.旨在采用正交实验设计考察相关因素对其最终产物PEG4000-MAL收率的影响,结果表明对其收率影响最大的因素为AT-PEG4000的氨基与马来酸酐摩尔比,最佳工艺条件是AT-PEG4000的氨基与马来酸酐摩尔比为1∶4,反应温度为100℃,反应时间为3h.经验证实验知此路线全程收率为87.2%.用红外光谱对产物结构进行了表征,证实最终合成产物即为PEG4000-MAL.     

An Experimental Study on the Particle Emission Characteristics of a Diesel Car During Cold Start

使用排气颗粒数量与粒径分析仪对一辆帕萨特柴油轿车进行了冷起动和热起动对比试验,研究其起动过程的颗粒排放特性.结果表明,柴油轿车冷起动颗粒排放数量浓度与热起动相比显著增加,其中,聚集态颗粒数量浓度增加明显,而核模态颗粒数量浓度差别不大;冷起动排放颗粒表面积浓度、体积浓度和质量浓度显著高于热起动;冷起动过程燃油消耗量也比热起动成倍增加.因此,冷起动不但造成颗粒排放恶化,且严重影响柴油轿车的燃油经济性.