装配式板桥的横向预应力设计

基于摩擦抗剪的概念,提出一种确定横向预应力张拉设计值的方法.计算表明:在考虑板间铰缝及混凝土桥面板纵向开裂的情形下,装配式板桥的横向联结性能随着横向预应力的增大而增加;但是当横向预应力水平达到一定的程度(如NPO)之后,其横向联结性能基本不变,横向预应力的设计张拉值应大干NPO.通过美国马里兰州的一座装配式实心板桥的车载试验,研究了横向预应力对桥梁横向联结性能的影响.理论及试验表明,当桥面板及铰缝没有纵向开裂时,板间具备了足够的荷载横向传递能力,横向预应力对桥梁的横向联结性能影响不大.但横向预应力的存在,保证了铰缝和铺装层开裂后桥梁具有良好的横向联结性能,可以有效地抑制纵向裂缝病害的发展,确保桥梁的使用性能和安全性.     

中日合办汉冶萍公司缘由探析

1908年,汉冶萍煤铁厂矿有限公司正式合并成立。同年,开始大规模招集商股;但汉冶萍公司合并后,即面临着重重困境。在经营困难,公司管理层与南京临时政府推动,及日本诱导等复杂因素的相互作用下,中日之间开始寻求合办汉冶萍公司。这一事件从侧面揭示了整个中国近代工矿企业发展的曲折脉络与复杂的经营环境。     

水体中5-HT对仔蟹生长以及内源5-HT水平的影响

已有研究表明外源给予一定量的5-羟色胺（5-HT）可以调控甲壳动物的发育.本实验将同期变态的Ⅰ期仔蟹（仔Ⅰ）单只浸泡于浓度分别为1,3和5μg/mL的5-HT中,浸泡时间分别为1,2和4d,每组20个平行,每个平行1只,待变态成Ⅱ期仔蟹（仔Ⅱ）后观察各组的存活率、变态时间、规格（壳长、壳宽和湿重）,并测体内5-HT含量...     

论建筑与景观的空间构成关系

基于建筑与景观的空间构成性质和特点,从建筑界面、空间限定要素、空间氛围3个层面论述了内外连续性、空间限定要素在构成上的拆解与空间氛围的整合,进而分析了建筑与景观的空间构成关系,提出了当代建筑与景观整合的目标取向为空间连续、结构契合及形象和谐.     

UUV编队协同应召搜索马尔可夫运动目标的方法

采用时齐马尔可夫链来模拟目标的规避运动，根据事发海域的水深映射图，估算出马尔可夫运动目标的位置转移概率。无人水下航行器编队在目标初始概率分布和位置转移概率已知的条件下，根据当前搜索结果不断对目标位置进行预测和更新。编队成员能共享目标位置信息，以获得较为准确的目标验后分布。然后采用一种新的分区实时贪婪搜索算法，得到无人水下航行器编队的最优搜索路径，从而以较高的搜索成功概率与较短的平均发现目标时间完成对目标的应召搜索。最后通过实例仿真，证明了该方法的有效性和优越性。此方法将对无人水下航行器编队的战法研究具有参考借鉴意义。     

Performances of improved Tent chaos-based FM radar signal

A novel algorithm is proposed to solve the poor performance problem of the Tent chaos-based frequency modulation(FM) signal for range-Doppler imaging,which takes it into complex multi-segment system by increasing its segments.The simulation results show that the effectiveness of the proposed algorithm,as well as the performance of the improved Tent FM signal is obvious in a multipath or noise propagation environment.     

Magma flow inferred from magnetic fabrics in Wanning gabbro pluton and diabase dykes, Hainan

Measurements of anisotropy of magnetic susceptibility (AMS) were performed on a gabbro pluton and 7 diabase dykes in the Wanning area, southeast Hainan Island. Rock magnetism showed that pseudo-single domain (PSD) to multidomain (MD) Ti-poor magnetite carries the magnetic fabric in the gabbro pluton whereas MD Ti-poor magnetite carries the magnetic fabric in the diabase dykes. The corrected anisotropy degree (Pj ) in most specimens was found to be less than 1.2 which is indicative of a possible flow-related magnetic fabric. The AMS eigenvectors within each site are generally well grouped. The maximum susceptibility axes (K1 ) of the gabbro pluton are inclined towards the north at low angles (< 30°). K1 axes of the diabase dykes are inclined towards the NNW and SSE with dip angles of ≤ 30°. From this study, it appears that the emplacement mode of the gabbro pluton was characterized by intrusion from the north to the south at a low angle whereas the diabase dykes were emplaced from the NNW to the SSE at low to moderate angles. This was verified by comparison of the rock fabric to the magnetic fabric. All of this evidence leads to the conclusion that the Wanning gabbro pluton and diabase dykes were the products of pulsative intrusion from the same magma chamber in the area far to the north of Wanning, which suggests that basic rocks may exist beneath the Indosin- ian granite in the area to the north of Wanning.     

对高校内部财务审计的认识和思考

当前扩大办学规模、提高整体办学实力己成为近阶段各高等学校改革发展的总体趋势。对于复杂的经济形势,加强内部控制管理成为高校内在需要,内部财务审计作为内部控制系统的组成部分,作为内部控制的再控制,成为高校加强财务管理的重要手段。