基于PRO/E的立爪装煤机虚拟样机与仿真分析

介绍了在Pro/Engineer环境下,进行履带式液压立爪装煤机工作装置三维实体建模、虚拟装配、动态模拟、干涉检查和运动仿真,并利用Pro/Engineer参数化特征及时修改设计以获得最佳设计方案,成功实现了装煤机工作装置在Pro/Engineer环境下的虚拟样机设计.     

定性仿真的发展及应用

定性仿真是以非数字手段处理信息输入、建模、行为分析和结果输出等仿真环节,通过定性模型推导系统的定性行为描述,是处理不完备信息的有效方法.文章介绍了定性仿真产生的背景、定性仿真的理论流派、应用及发展.     

机场行李提取中行李箱图像识别与旋转仿真

为了减少机场旅客提取行李的时间,缓解机场拥挤问题,设计了一种行李箱自动识别和旋转系统。该系统主要包括行李箱图像预处理和角度计算与旋转两大部分。图像预处理对行李箱图像进行灰度处理、运用中值滤波对行李箱图像进行降噪、对行李箱图像进行二值化处理;然后对图像中有效轮廓进行截取;最后计算行李箱旋转角度并进行旋转。通过应用Matlab仿真验证了本文所提出的图像识别、处理和角度计算等的有效性和适用性。将行李箱把手旋转到靠近旅客的一侧可达到缩短旅客提取行李箱的时间,促进机场高效运行的目标,符合机场运营的需要,能够提高机场的运营和管理水平。     

磁刺激治疗仪的设计与仿真

设计了1种可以进行调幅、调频控制的磁刺激治疗仪。采用MAX038信号发生器产生正弦信号,经过OPA549进行功率放大,通过单片机控制刺激时间、信号幅度和频率,并应用六位数码管显示信号幅值、频率、时间等参数。采用Ansoft有限元分析软件对磁场探头进行了磁场仿真,为磁刺激器治疗强度的设定提供了理论依据和参考标准。     

Quasi-Monte Carlo methods in stochastic simulations: An application to policy simulations using a disequilibrium model of the West German economy 1960–1994

Different stochastic simulation methods are used in order to check the robustness of the outcome of policy simulations. The application of a macroeconometric disequilibrium model of the West German economy to a fiscal policy simulation is taken as an example. Due to nonlinearities arising from regime specific reactions inside the model, confidence intervals for the simulation results have to be obtained by means of stochastic simulations. The robustness of the results is assessed using different methodologies. In particular, different methods for the generation of uniform error terms and their conversion to normal variates are applied. These methods include standard approaches as well as quasi-Monte Carlo methods. First version received: May 1998/final version accepted: August 1999     

炼钢—精炼—连铸生产系统的计算机模拟分析

运用计算机模拟的方法，以宝钢为对象，对炼钢─—精炼─—连铸生产系统进行分析，并依据实际生产情况建立计算机模拟模型模拟，编制出相关程序。通过系统模拟，分析各种关键因素对生产计划执行过程的影响．提出编制连铸生产计划时应考虑的问题。     

京津冀都市圈经济增长的空间极化及其模拟研究

在利用空间极化指标对京津冀都市圈1993—2007年的空间极化变化趋势进行测算的基础上,采用GIS空间分析技术的二维和三维空间表达形式,对近15年来京津冀都市圈经济极化增长进行空间模拟,从时间和空间两个维度分析京津冀都市圈空间极化过程。得出的主要结论:①京津冀都市圈经济增长极化随时间呈上升趋势。②京津冀都市圈经济增长自经济中心向外围的变化趋势并不完全遵循距离衰减规律,离经济增长中心80km处是京津冀都市圈经济增长的低谷点。③从京津冀都市圈立体趋势面分析,北京和天津是京津冀都市圈的两大极核,且空间极化趋势面随时间呈扩大趋势。     

基于东软创投的风险投资公司价值评估研究

风险投资是目前高科技企业注入资金的主要来源。风险投资者只有准确地把握被投资高科技企业的企业价值,才能保证风险投资市场的健康发展,才能保证有发展前景的高科技企业得到充足的发展资金。为此,改进与完善高科技企业价值评估方法体系尤为重要。     

The effects of tax reform on labor supply, tax revenue and welfare when tax avoidance matters

We examine how tax avoidance in the form of trade in well-functioning asset markets affects the study of labor supply. We discuss the implications for tax policy analysis, and we show that a failure to account for avoidance responses may lead to huge errors when analyzing how tax reform affects labor supply, tax revenue and the welfare cost of taxation. Our model may explain a number of otherwise hard to understand dimensions of taxpayer response.     

Incentives to lead,follow, or compete: comparative national choices of international copyright

I study the desirability and incentives for countries to lead or follow in international copyright policy making by analyzing a lead-follow model of international copyright and comparing it with a competitive model. The analyses suggest that the lead-follow model is globally preferable except when the information products have short economic life in the leading country. In this exceptional case, the incentives of individual countries are compatible with global welfare as they also prefer the globally preferable competitive model. However, in the cases where the lead-follow model is globally preferable, individual countries do not always have the incentive to lead or follow. For example, a small country may prefer competition over leading or following, as competition may allow it to free-ride on the copyright protection provided by the larger country. This suggests that ‘extraordinary’ incentive is sometimes needed to induce individual countries to adopt the lead-follow model of international copyright when it is globally desirable.