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181.
An artificial neural network model for backside bead width was established and three control meth-ods——PID. fuzzy and neuron were designed, simulated and tested. The test results of bead-on-plate weld of GTAW indicate that the artificial neural network (ANN) modeling and learning control method have more advan-tages than the conventional method. They show that the ANN modeling and learning control method is an effective approach to real time control of welding dynamics and ideal quality. 相似文献
182.
某重型钢水罐车车架结构的有限元分析及优化 总被引:1,自引:0,他引:1
以某车架为研究对象,采用参数化有限元分析方法,进行了弯曲工况下应力和应变的计算。通过电测量验证了有限元模型的正确性,进而以车架的体积为目标,对车架进行了参数化模型的结构优化,得到了满足结构强度的最佳方案。 相似文献
183.
基于有限理性的顾客满意及其对策研究 总被引:3,自引:0,他引:3
顾客满意是提高企业竞争力的重要措施。在综述了国内外有关顾客满意理论研究的基础上,讨论了基于有限理性的顾客和顾客满意的本质含义;然后建立了多变量顾客满意的模型,辨析了构成顾客满意模型的多变量之间的关系。最后,从企业形象战略的再塑、全面顾客满意、可视化柔性决策和客户关系管理4个方面对顾客满意的对策进行了研究。 相似文献
184.
分析了已有的面向Agent软件工程方法中Agent建模存在的问题,针对Agent的并发性和不确定性的特点,提出了采用具有不确定性和并发性特点的ConGolog语言描述Agent建模的方法。所建议的方法不仅给出了Agent的语义、形式化描述,并且能对Agent的模型进行验证。 相似文献
185.
平面二次包络环面蜗轮副三维实体属复杂曲面造型,文章在坐标变换公式的基础上,讨论了环面蜗杆螺旋齿面方程,建立了环面蜗杆螺旋线参数方程,并用VBA编程建模.按此建模,用平面包络环面蜗杆产型齿的特征模型,在MDT6.0三维绘图软件环境中实现平面包络环面蜗杆和二次包络蜗轮副的三维建模,并以断面图检验了其良好的接触啮合状态.所生成的实体模型具有给定参数的数字信息,可用于此类环面蜗杆的齿廓形状分析和进一步应用研究. 相似文献
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Traffic congestion has been a growing issue in many metropolitan areas during recent years, which necessitates the identification of its key contributors and development of sustainable strategies to help decrease its adverse impacts on traffic networks. Road incidents generally and crashes specifically have been acknowledged as the cause of a large proportion of travel delays in urban areas and account for 25% to 60% of traffic congestion on motorways. Identifying the critical determinants of travel delays has been of significant importance to the incident management systems, which constantly collect and store the incident duration data. This study investigates the individual and simultaneous differential effects of the relevant determinants on motorway crash duration probabilities. In particular, it applies parametric Accelerated Failure Time (AFT) hazard‐based models to develop in‐depth insights into how the crash‐specific characteristic and the associated temporal and infrastructural determinants impact the duration. AFT models with both fixed and random parameters have been calibrated on one year of traffic crash records from two major Australian motorways in South East Queensland, and the differential effects of determinants on crash survival functions have been studied on these two motorways individually. A comprehensive spectrum of commonly used parametric fixed parameter AFT models, including generalized gamma and generalized F families, has been compared with random parameter AFT structures in terms of goodness of fit to the duration data, and as a result, the random parameter Weibull AFT model has been selected as the most appropriate model. Significant determinants of motorway crash duration included traffic diversion requirement, crash injury type, number and type of vehicles involved in a crash, day of week and time of day, towing support requirement and damage to the infrastructure. A major finding of this research is that the motorways under study are significantly different in terms of crash durations; such that motorway 1 exhibits durations that are on average 19% shorter compared with the durations on motorway 2. The differential effects of explanatory variables on crash durations are also different on the two motorways. The detailed presented analysis confirms that looking at the motorway network as a whole, neglecting the individual differences between roads, can lead to erroneous interpretations of duration and inefficient strategies for mitigating travel delays along a particular motorway. 相似文献
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