The Optimal Solution of the Model with Physical and Human Capital Adjustment Costs

We prove that the model with physical and human capital adjustment costs has optimal solution when the production function is increasing return and the structure of vetor fields of the model changes substantially when the prodution function from decreasing return turns to increasing return. And it is shown that the economy is improved when the coefficients of adjustment costs become small.     

浅谈饭店"环境入世"

环境恶化，生态平衡破坏，使对可持续发展的研究愈来愈重要．通过对饭店经营观念的转变。创建绿色饭店环境成本和效益的分析，提出实现饭店可持续发展的途径．     

高速磁浮曲线地段简支轨道梁墩体系动力响应仿真

应用桥梁动力学、车辆动力学和电磁相互作用原理建立了高速常导磁浮交通车-梁-墩体系动力分析模型,利用数值积分求解了大规模非线性耦合动力方程.在此基础上结合具体线路条件进行了车线耦合动力学检算,得到了曲线地段车辆及梁墩体系动力响应基本规律.该部分的研究为制订合理的高速磁浮线路设计标准提供了理论依据.     

基于相对业绩比较的报酬契约与代理成本分析

有效的报酬契约是企业所有者激励经营者努力工作的最佳动力，该文在考虑了相对业绩比较信息条件下，运用委托代理理论探讨了将货币收入和享受闲暇作为经营者的激励物的最优报酬契约，分析了非对称信息条件下实施契约的代理成本，得出了经营者利润分享系数与影响因素之间的关系模型以及代理成本与影响因素之间的关系模型，该文还设计了经营者的股票期权激励机制，并地某些企业作了案例分析，文章阐明股票期权激励能够将经营者的长期行为和利益与企业的长期目标结合起来，是调动经营者积极性的有效手段。     

基于多Agent的交通运输枢纽虚拟组织信息集成框架

面对动态、快速、多变的市场环境 ,虚拟企业开始出现并得以快速发展 ,传统的交通运输枢纽有了新的要求 .在虚拟企业思想的启示下 ,本文试用系统的观点提出作为结合部的交通运输枢纽虚拟组织的概念、特点 ,并指出其信息管理的重要性 .接着在基于多 Agent系统的基础上对其进行分析 ,给出交通运输枢纽虚拟组织信息集成框架 ,并利用面向对象的 Agent进行设计 .最后提出了今后的研究方案 .     

最优吸收截面的存在性

对被真空包围的无穷平行平板，运用勒贝格控制收敛定理和Ｃａｕｃｈｙ－Ｓｃｈｗａｒｔｙ不等式，给出稳态中子迁移系统最优吸收截面的存在性。     

运输需求的特性及其分析特点

研究了运输需求的概念和特性，粗略地总结了运输需求的广泛性、多样性、派生性、空间特定性、时间特定性和部分可替代性６个主要特征，说明运输需求包括流量、流向、流程、流时和流速５个要素。并分析了运输需求的产生原因，讨论了运输需求分析的特点，论述了微观经济学需求理论用于运输需求分析的局限性。     

佛山市城市公共交通发展策略

通过对佛山市公共交通客流和公共交通设施现状的调查，掌握了居民出行规律和客运交通特征指标．采用定性和定量相结合的方法，综合评价了公共交通现状的水平．在分析佛山市未来社会经济、城市发展基本特征的基础上，根据客流分布特点、发展态势及客流交通的生成变化特征，采用经验加模型系统方法，科学地预测发展需求．结合佛山市的实际，分析了公共交通的优劣势，确定了优先发展公共交通的方针与目标．对公共交通政策进行了研究，并提出确保实施公共交通目标的对策和措施     

Simulation of the diffusion process in composite porous media by random walks

A new random-walk interpolation scheme was developed to simulate solute transport through composite porous media with different porosities as well as different diffusivities. The significant influences of the abrupt variations of porosity and diffusivity on solute transport were simulated by tracking random walkers through a linear interpolation domain across the heterogeneity interface. The displacements of the random walkers within the interpolation region were obtained explicitly by establishing the equivalence between the Fokker-Planck equation and the advection-dispersion equation. Applications indicate that the random-walk interpolation method can simulate one- and two-dimensional, 2nd-order diffusion processes in composite media without local mass conservation errors. In addition, both the theoretical derivations and the numerical simulations show that the drift and dispersion of particles depend on the type of Markov process selected to reflect the dynamics of random walkers. If the nonlinear Langevin equation is used, the gradient of porosity and the gradient of diffusivity strongly affect the drift displacement of particles. Therefore, random-walking particles driven by the gradient of porosity, the gradient of diffusivity, and the random diffusion, can imitate the transport of solute under only pure diffusion in composite porous media containing abrupt variations of porosity and diffusivity.     

Bromocriptine-induced removal of endoplasmic membranes from prolactinoma cells

Summary Adenomatous prolactin cells lose 39% of their cytoplasm volume within 7 days after the beginning of bromocriptine treatment. A simultaneous reduction of the rough-surfaced endoplasmic reticulum and the Golgi apparatus occurs. Their membranes are removed by rapid transport along the secretory pathway to the cell surface and to lysosomal destruction.We thank Prof. E. del Pozo, Sandoz Ltd, Basle, for the generous gift of injectable bromocriptine, Prof. E.R. Weibel, Dept. of Anatomy, University of Bern, for his technical advice, Dr U. Helfenstein, Institute of Biostatistics, University of Zürich, for his help in the statistical evaluation of the results and the EMDO-Foundation, Zürich, for financial support.