基于改进SLP理论的铁路电商物流中心布局研究

通过研究电子商务环境下铁路物流中心的作业情况,将铁路电商物流中心划分为收货区、存储区、拣货区、包装区、发货区、退货区、设备区和办公区8个功能区域。对系统布置规划（SLP）进行量化改造,加入数学建模的方法对物流影响因素进行量化分析。按照改进SLP方法对影响铁路电商物流中心的物流因素和非物流因素进行分析,并构建综合关系表。在功能区间不重叠、功能区不能超过规划范围、铁路长宽比有一定范围、不得占用铁路专用线区域、园区出入口等的约束条件下,建立了园区内物料搬运成本最小、功能区间综合关系最大、土地改造成本最小的目标函数,然后对目标函数进行处理得到归一化的单目标函数。通过改进遗传算法进行求解,从而得到科学合理的布局规划方案。实际应用的算例分析表明,本文中布局方法具有科学合理性。     

考虑表面应力的微悬臂梁质量传感器的建模与仿真

为了考虑悬臂梁谐振器表面吸附层或者不同材料涂层引起的表面应力的影响,进而提高质量传感器的精度和性能,基于瑞利-里兹法提出了考虑表面应力的悬臂梁质量传感器的理论方法.在悬臂梁振动的控制方程中引入应力系数对其振型函数进行修正,并系统地分析对悬臂梁振动频率的影响,再根据瑞利法建立微悬臂梁质量传感器的理论模型.应用该方法,纳米颗粒的位置和质量可以通过颗粒吸附前后悬臂梁的频率移动来精确确定.该方法的准确性和可行性通过有限元仿真进行了验证.     

基于可拓理论的边坡强度指标

基于可拓理论,从3个层次5个指标建立了边坡稳定性评价指标体系,研究了内摩擦角和黏聚力对边坡稳定性的影响,给出了抗剪强度参数与安全系数之间的数量关系.研究结果表明:随内摩擦角和黏聚力的增大安全系数呈线性增大,且内摩擦角对安全系数的敏感性明显大于黏聚力对安全系数的敏感性.最后,基于安全、经济、高效的原则,采用锚杆措施对辽宁省小盘岭边坡进行加固处理.     

The problem of dependent evidence

It is appropriate to use Dempster's rule for combining belief functions only if the belief functions combined are based on independent items of evidence. What can be done in the case of dependent evidence? Often the answer is to reframe the problem. Three examples are given: one from everyday experience, one from probabilistic relaxation, and one from expert systems.     

The raised-cosine wavelets in computerized tomography

In Computerized Tomography (CT), an image must be recovered from its sampled projections in the form of values of the Radon transform. In this work a method of recovering the image is based on the properties of the raised-cosine wavelet. This wavelet has a closed form which allows for certain precomputations and avoids convolution. The rate of convergence of the resulting algorithm to the image density function is found under suitable hypotheses. This algorithm is then tested on the standard Shepp–Logan     

Structure and cooperativity of the hydrogen bonds in sodium dihydrogen triacetate

Geometry and energetics of low energy conformers of sodium dihydrogen triacetate (SDHTA) and its anion are studied using density functional theory (DFT) at the Becke, Lee‐Yang‐Parr hybrid functional (BLYP) and Becke, three‐parameter, Lee‐Yang‐Parr hybrid functional (B3LYP) levels. For both cases, two structures of comparable energy are found, which have different symmetry with respect to the two hydrogen bonds (HBs). DFT‐based Born–Oppenheimer molecular dynamics simulations are performed for SDHTA, which show that both structures are visited at room temperature conditions. The trajectory analysis further reveals that the two HBs behave anticooperative, that is, on average elongation of one HB is accompanied by a compression of the other one. This is in accord with nuclear magnetic resonance (NMR) experimental studies for a similar counter ion–dihydrogen triacetate complex. © 2012 Wiley Periodicals, Inc.     

Relevance and truthfulness in information correction and fusion

A general approach to information correction and fusion for belief functions is proposed, where not only may the information items be irrelevant, but sources may lie as well. We introduce a new correction scheme, which takes into account uncertain metaknowledge on the source’s relevance and truthfulness and that generalizes Shafer’s discounting operation. We then show how to reinterpret all connectives of Boolean logic in terms of source behavior assumptions with respect to relevance and truthfulness. We are led to generalize the unnormalized Dempster’s rule to all Boolean connectives, while taking into account the uncertainties pertaining to assumptions concerning the behavior of sources. Eventually, we further extend this approach to an even more general setting, where source behavior assumptions do not have to be restricted to relevance and truthfulness. We also establish the commutativity property between correction and fusion processes, when the behaviors of the sources are independent.     

Biaxial nematics: symmetries,order domains and field-induced phase transitions †

We studied the symmetry and spatial uniformity of the orientational order of the biaxial nematic phase in the light of recent experimental observations of phase biaxiality in thermotropic bent-core and calamitic-tetramer nematics. Evidence is presented supporting monoclinic symmetry, instead of the usually assumed orthorhombic symmetry. The use of deuterium nuclear magnetic resonance to differentiate between the possible symmetries is described. The spatial aspects of biaxial order are presented in the context of the cluster model, wherein macroscopic biaxiality can result from the field-induced alignment of biaxial and possibly polar domains. The implications of different symmetries on the alignment of biaxial nematics and on the measurements of biaxial order are discussed in conjunction with the microdomain structure of the biaxial phase.     

粒子物理中几种可能应用的新数学方法和拓扑模型

在粒子物理中探讨了四元数、符号动力学等新的数学方法,几种可能应用于振荡的数学方法,及与时间有关的粒子理论;讨论了非线性理论和相应的定性分析理论的结果;研究了粒子的拓扑模型和分形模型;最后提出弱相互作用可能相应于Lobachevsky几何.