Prediction of the paper path in a laser printer by finite element analysis

A conventional problem of paper handling in a page-printing printer is to design a reliable paper path. Sometimes, this also affects the printing quality. The nonlinear theory of elastica has often been used to model paper deflection shape and to predict the paper path between some guiding rollers. The present paper proposes another method that can solve this problem more efficiently. Considering a piece of paper as a nonlinear beam, finite element analysis with geometric nonlinearity and manipulating the contact gap element between paper and guiding surfaces can be used to simulate the large-deflection behavior of paper. In this paper, the paper path in the vicinity of an OPC (organic photoconductive) drum is investigated with a general purpose finite element package. The effect of the electrostatic force between the OPC drum and the paper is considered, and the deformed shape of the paper for different forces lengths is obtained. According to those results an appropriate paper guide is added for an exact paper path.     

曲线拐点充分条件证明中的常见错误

文[1]给出了判别曲线拐点的两个充分条件,文[2]给出了一个充分条件,但三个定理的证明都是错误的.同时,文[1]的两个推论也是错误的.本文通过反例分析了其错因,并给出了文[1]中一个拐点充分条件的正确证明.     

Capillary hydrodynamics of the deposition of thin films and droplets on heterogeneous,porous substrates

The work presented here deals with recent research on capillary hydrodynamics of thin viscous liquid films and droplets. The process engineering background comes from the industrial process to deposit thin films or droplets on substrates such as polymer foils or paper [1, 2, 3]. During the production of paper, for example, layers of coating color have to be applied onto the raw paper in order to ensure its usability. Ink–jet paper consists of several different functional layers to optimize the paper with regard to printing quality or paper handling. For the printing process by the ink–jet technique, a controlled application of droplets onto the paper and subsequent penetration of the fluid into the paper are crucial for the final quality of the print. The work summarized here considers the application of films or droplets on substrates as well as the flow of liquids inside porous media. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)     

用DEA估计生产力进步的探讨

有关生产力进步的概念与计算,文［１］、［２］基于规模报酬不变的生产前沿面来研究,本文推广到基于一般生产前沿面来研究．因此本文在讨论中用面向输出的Ｃ２ＧＳ２模型而不是文［１］、［２］中所用的面向输入的Ｃ２Ｒ模型．     

Dynamical problems for geometrically exact theories of nonlinearly viscoelastic rods

Summary This paper surveys recent results and open problems for the equations of motion for geometrically exact theories of nonlinearly viscoelastic and elastic rods. These rods can deform in space by undergoing not only flexure and torsion, but also extension and shear. The paper begins with a derivation of the governing equations, which for viscoelastic rods form a quasilinear system of hyperbolic-parabolic partial differential equations of high order. It then derives the energy equation and discusses difficulties that can arise in getting useful energy estimates. The paper next treats constitutive assumptions precluding total compression. The paper then discusses the curious asymptotic problems that arise when the inertia of the rod is small relative to that of a rigid body attached to its end. The paper concludes with discussions of traveling waves and shock structure, Hopf bifurcation problems, and problems of control. This paper is dedicated to the memory of Juan C. Simo This paper was solicited by the editors to be part of a volume dedicated to the memory of Juan Simo.     

若干家族p-群的自同构群的阶

本文确定了Rodney James文章中P．Hall isoclinism族第一家族到第十家族所有群的自同构群的阶,并纠正了Rodney James文章里的某些错误．     

投资收益相依性的风险模型

本文首先提出了投资收益相依性的风险模型并给出了其风险模型的破产概率,并且讨论了在双项投资的情况下如何合理分配使得保险公司取得最佳经营.最后给出在多项投资情况下的分配方案.     

试卷质量的灰色综合评判

李文革．试卷质量的灰色综合评判．数理统计与管理，１９９７，１６（４），４２～４５．本文运用灰色综合评判评价了文［１］中的七套试卷，得到了与文［１］不同的结果，但本文的结果更符合客观实际。     

Tanker chartering: A system dynamics case study

This paper describes a practical system dynamics case study. It attempts to show how this OR technique can be applied to a practical problem and the results which it can, and cannot, be expected to give.Although the paper is based on a real project, the details have been altered for commercial secrecy, and the emphasis in this paper is, for the same reason, rather different from that of the original work. The aim of the paper is, therefore, to give enough of a “real” background to contrast the industrial application of SD with some of its other applications.For the sake of reasonable brevity, the emphasis in this paper is on the managerial viewpoint, and the extent to which an SD model provides helpful answers to managerial questions. The model paper is described only briefly as full details, and a model listing are given by Coyle. Some other aspects of the system are treated by Winch.     

"求线性规划问题可行基的一种方法"的注记

文[2]通过两个反例的计算,认为文[1]所提出的求LP可行基的方法有不妥之处,并对[1]的方法中主要步骤作了修正。本文对[1]的算法中轴心项的选取作进一步说明,对[2]中所提出的反例以[1]中算法进行计算与[2]对比分析,说明[2]中的反例并不成立。     

碎纸片的拼接复原方法研究

本文研究了来自同一页印刷品的中、英文文字文件,在规则的横、纵切割方式下,碎纸片的拼接复原方法.文中利用碎纸片图片边缘灰度值数据的匹配度和行间距、字高等文字排版数据,建立了一系列拼接复原模型.首先对仅纵切方式下的碎纸片拼接问题,建立了基于碎片边缘匹配的图像拼接复原模型,根据碎片边缘灰度值向量间的距离来衡量两张图片的匹配度.然后对中、英文碎纸片分别提出基于像素点投影和灰度计数的分类方法,将处在同一行的碎片分为一类,使用拼接复原模型完成行内的拼接.最后通过行间距信息完成了行与行之间的匹配,从而完成了整份文件的拼接复原.     

Josef Meixner: His life and his orthogonal polynomials

This paper starts with a biographical sketch of the life of Josef Meixner. Then his motivations to work on orthogonal polynomials and special functions are reviewed. Meixner’s 1934 paper introducing the Meixner and Meixner–Pollaczek polynomials is discussed in detail. Truksa’s forgotten 1931 paper, which already contains the Meixner polynomials, is mentioned. The paper ends with a survey of the reception of Meixner’s 1934 paper.     

企业库存问题研究－离散事件的动态模拟

本文在详细占有统计数据的基础上，对玻壳厂的库存问题进行了研究，并用统计实验方法作了动态模拟，得到了可供选择的较优解。本文的方法和度序原则上也适用于其它生产企业和商业机构甚至后勤部门。     

Some remarks on nonlinear consolidation models

This paper deals with the modelling of nonlinear consolidation phenomena in a homogenous clay changing from an over to a normal consolidation regime. Specifically this paper develops a technical analysis of the model under the assumption of small deformations to derive a new class of models and to show how classical models known in the literature can be regarded as a particular case of the one dealt with in this paper.     

考虑成本因素的税企博弈模型

本在献[1]的基础上,进一步考虑成本因素在更为一般的条件下建立了新的税企博弈模型,得到国家税务机关最优混合策略及其骗税罚款系数公式,并且指出献[1]的结论是本的一个推论。     

On the application of a transportation model for revenue optimization in waste management: a case study

This paper describes an interactive decision support system called Opti-Link which has been developed for a company operating in the area of waste and raw material management. Built around a specific transportation problem, the system is used to maximize the revenue generated by selling waste paper to paper mills. Furthermore, the dual variables of the linear program allow the planner to identify upper bounds for setting bid prices to buy waste paper from waste collection companies. First operational results indicate a significant increase in profit while at the same time the duration of the planning process could be cut by more than half.     

O.R. Applications in Industry and Problems of Industrialisation of a Developing Economy with Special Reference to India

The paper has two distinct parts. The first part reviews industrial applications of O.R. in developing countries in general and India in particular. Based on the analysis, the paper suggests concrete steps for further use of operational research in industry.The second part of the paper deals critically with the problems of industrialisation leading to a specific industrial structure in the economy of a developing country. Analysing various relevant criteria for industrialisation of developing economies the paper outlines a methodology suitable for modelling the problem. It then attempts to identify the prerequisites for successful use of O.R. in the multicriteria problem of industrialisation. The paper also discusses the role that national and international agencies can play in bringing about more meaningful applications of O.R. in developing economies.     

企业库存问题研究－离散事件的动态模拟

本文在详细占有统计数据的基础上，对玻壳厂的库存问题进行了研究，并用统计实验方法作了动态模拟，得到了可供选择的较优解。本文的方法和度序原则上也适用于其它生产企业和商业机构甚至后勤部门。     

A fuzzy approach to using expert knowledge for tuning paper machines

Paper machines are very complex production systems, but their scope is simple: they consume materials and resources, called factors, to produce paper, which in turn can be described by its characteristics. In this paper, a decision support system is developed in cooperation with an industrial partner to help them with operational decision making when tuning a paper machine. The decision support system was developed in two phases. Firstly, the knowledge of experts is collected and stored in the form of a fuzzy ontology. Secondly, this knowledge is made usable so that a user of the decision support system can specify what characteristics of the produced paper to increase or to decrease and be returned with a recommendation on what factors to change. In this paper, we will work out the optimization problems on which the system is based. Additionally to a basic goal programming model, two extensions are explored, accounting for uncertainty and non-linearity, respectively.     

系统动力学在建设工程风险识别中的应用

首先根据建设工程建设程序,提出了建设工程建设阶段的风险管理.简单综述了系统动力学在项目管理中的应用,然后选取在项目实施期间,以项目承包商的视角,应用系统动力学方法对项目进行风险识别.由于篇幅所限,仅以工期风险为例,详细识别了造成工期风险的原因和风险发生后引起的后果,以及风险发生后通过系统内部调节后对自身的影响,证明了系统动力学在风险识别阶段应用的可行性和优越性.