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探讨了产品综合成本的构成,以此为基础提出了以产品综合成本最低为目标的公差稳健设计模型,并利用双响应面法(Response Surface Methodology ,RSM) 来实现公差的稳健优化设计。  相似文献   

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A field failure in certain products has the potential to cause human suffering and/or loss of life. To the manufacturer, these failures will result in a significant external failure cost. In this paper, cost minimization models are developed to determine an optimal inspection system for multiple 100% attribute inspections with inspection error. An example involving the visual inspection of a braze joint in a cardiac biopsy device is presented to illustrate the use of the models. A key result is that a system requiring an item to pass every inspection in order to be shipped to a customer is not always the best alternative. Examples illustrating the sensitivity of the model results to key cost and operational parameters are shown.  相似文献   

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基于ERP的实际成本核算系统的设计与实现   总被引:2,自引:0,他引:2  
主要介绍了机械加工企业成本核算系统的方案论证、结构特性设计、系统功能模型和实现流程,并结合许昌烟机实际情况,分析了成本控制的关键因素和具体措施.该系统的投入使用使月末报表时间由四天缩短到两三个小时,成本控制能力得到显著提高.  相似文献   

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针对参数不确定非线性系统的鲁棒镇定和鲁棒跟踪问题,提出了一种基于Lyapunov稳定性理论的非线性动态鲁棒控制器设计方法,将设计过程分为两步,第一步是针对标系统设计使其实现控制目标的控制器,第二步是在第一步的基础上,进一步设计控制器抑制由于不确定性因素所产生的原系统与标称系统之间的偏差,其优点是在设计的第一步可以直接利用基于精确数学模型建立的非线性控制系统设计方法,数值仿真验证了设计方法的正确性。  相似文献   

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We consider a replacement policy for a multiple-component cold-standby system,and atfer we analyze this plicy,we want to get the mean total cost rate and the preventive policy to make it the lowest.In this system,the failure rate of the component in poeration is constant,and the inspection will control all the processes of the operation.The system is inspected at random points over time to determine whether it is to be replaced.During the process,the replacement decision is based on the number of failed components at the time of inspection.  相似文献   

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This paper develops a new solution procedure for obtaining the joint probability density function (PDF) of non-linear energy harvesters under Poisson impulses using the state-space-split method and the exponential-polynomial closure method. In the beginning, a generic electromechanical energy harvester is introduced and its governing equations are transformed into non-dimensional ones. According to the non-dimensional governing equations, a Duffing-type oscillator with piezoelectric conversion mechanism is further considered in this study. The proposed solution procedure includes three steps. First the joint PDF of this system is governed by the generalized Fokker-Plank-Kolmogorov (FPK) equation. The state-space-split method is used to reduce this generalized FPK equation to a low-dimensional one only about displacement and velocity. After that, the exponential-polynomial closure method is further adopted to solve the reduced FPK equation. Finally, the joint PDF of displacement, velocity and voltage can be approximated by the product of the obtained PDF and the conditional Gaussian PDF of voltage. Four cases are investigated considering the effects of non-linearity coefficient, impulse arrival rate and a bistable Duffing oscillator. The PDFs of these state variables and the harvested power are compared with the simulation results, respectively. The good agreement between the obtained PDFs and the simulated results is achieved. Compared with the results of the equivalent linearization method, the strong non-linearity in displacement and lower impulse rate lead the tail PDF of the harvested power to exhibiting hardening and softening behaviors, respectively. For the bistable Duffing oscillator, the PDF of the harvested power differs significantly from the result of the equivalent linearization method in the tail region.  相似文献   

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在建立公差--成本模型的基础上,提出了以制造成本最低为目标的机械产品零部件公差优化设计方法,并进行了实例分析计算。采用该方法在产品大批量生产条件下将会产生明显的经济效益。  相似文献   

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Reinforced concrete (RC) as a material is most commonly used for buildings construction. Several floor systems are available following the structural and architectural requirements. The current research study provides cost and input energy comparisons of RC office buildings of different floor systems. Conventional solid, ribbed, flat plate and flat slab systems are considered in the study. Building models in three-dimensional using extended three-dimensional analysis of building systems (ETABS) and in two-dimensional using slab analysis by the finite element (SAFE) are developed for analysis purposes. Analysis and design using both software packages and manual calculations are employed to obtain the optimum sections and reinforcements to fit cities of low seismic intensities for all the considered building systems. Two ground motion records of low peak ground acceleration (PGA) levels are used to excite the models to measure the input energies. Uniformat cost estimating system is adopted to categorize building components according to 12 divisions. Also, Microsoft (MS) Project is utilized to identify the construction cost and duration of each building system. The study shows that floor system significantly causes changes in the input energy to structures. In addition, the slight increase in the PGA increases the amount of input energy particularly flat plate system. Estimated cost of the flat plate system that the flat slab system is of higher value as compared to ribbed and conventional slab systems. The use of drop panels increases this value as well. Moreover, the estimated cost of the ribbed slab system exceeds that of conventional system.  相似文献   

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切换系统是一种重要的混杂系统,由若干子系统及决定子系统之间切换的切换信号组成。在工程应用中,控制器切换与子系统的切换会存在时延,即异步切换。研究了异步切换下的时变时滞系统的保成本控制问题,利用分段李雅普诺夫函数法和平均驻留时间法,得到保成本控制器存在的充分条件,并从线性矩阵不等式的角度,设计了一个异步切换保成本控制器,使得系统具有鲁棒性能。最后,给出了一个数值例子验证提出的方法的有效性。  相似文献   

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Design For Cost (DFC) is a branch of Design For X (DFX). In this paper, we defined DFC as a design method that analyzed and evaluated the product‘s life cycle cost (LCC), then modified the design to reduce the LCC. Nowadays it is a very difficult thing to obtain LCC data in China or in developing countries. Statistical methods can not be used because available LCC data are few. In order to solve this problem, we used grey system theory. Then relations of cost factors were analyzed in LCC using grey relevant methods, and a GM( 1,1 ) model between design parameters and LCC was established. Using this model, we can estimate and control LCC by changing design parameters at the beginning of the design stage.  相似文献   

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夏进军  杨榕榕  周涛  王帅 《包装工程》2019,40(8):169-175
目的探索在产品创新设计阶段如何依托成本控制理念,实施产品创新设计,并权衡设计、功能、成本之间的关系。方法以望江轻便两用摩托车设计实践项目为例,从预防性成本控制与前馈性成本控制两个角度出发,探讨如何展开设计准备工作,并从产品造型、结构、材料、装饰等4个方面,对初步方案进行设计、成本分析和方案改进,最终形成基于成本预算与方案满意度评价的方案决策。结论以案例实证方式,验证在产品创新设计阶段,将成本控制理念与方法融入创新设计中,对设计方案进行辅助性方案评价、修改与决策,能够有效权衡创新设计、功能、成本等因素,更准确地把握设计方向并提升产品创新设计可实施性,为产品创新设计阶段的成本控制与设计创新提供新思路。  相似文献   

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本文以实际产品“水轮机”为技术依托,提出了在技术成型、产品结构相对稳定的情况下,对单件、小批量、大规模生产类型的特大型机械产品在开发过程中进行成本控制的方法及过程。  相似文献   

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在DFC概念模型的基础上,将面向成本的设计引入复合材料结构设计当中,建立复合材料结构的面向成本设计的理论框架;在对成本估算模型分类的基础上,针对复合材料面向成本设计过程中各个阶段的特点,选择其相应的成本估算方法。  相似文献   

16.
孙韵  叶颖  金江 《材料导报》2007,21(F05):150-152
用沉淀法中的氯化铝一硫酸铝铵反应体系制备纳米氧化铝原料便宜,工艺简单,制得的粉体纯度高,粒径小。用正交实验优化了其主要反应条件,以表面活性剂为分散剂,制备出了成本低、质量较好的纳米氧化铝。经粗略计算,成本约为30元/kg。  相似文献   

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作为一类重要的混杂系统,切换系统由若干个子系统以及一个协调各子系统之间切换的切换信号构成,在自然科学、工程控制和社会系统等方面有着广泛的应用。在对切换系统的控制问题进行研究时,一般假设子系统和控制器同步运行。然而,在实际工程控制中,控制器的切换相对于子系统的切换存在切换时延,从而产生异步切换。因此,对异步切换下的切换系统研究是十分必要的。针对一类异步切换下切换系统的动态输出反馈保成本控制问题进行了研究。报告了切换系统的研究现状以及异步切换下切换系统的最新研究成果。利用分段李雅普诺夫函数法和平均驻留时间法,得到了使得异步切换下的闭环切换系统稳定的动态输出反馈控制器存在的充分条件。从线性矩阵不等式的角度,提出了异步切换动态输出反馈保成本控制器设计方案,并给出成本上界的优化方法。最后,通过一个数值算例说明了提出的方法的有效性。  相似文献   

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The robust parameter design of industrial processes and products on the basis of the concept of building quality into a design has attracted much attention from researchers and practitioners for many years, and several methods have been studied in the research community. Dual response surface methodology is one of the most commonly used approaches for simultaneously optimizing the mean and the variance of response in quality engineering. Nevertheless, when the relationship between influential input factors and output quality characteristics of a process is very complex (e.g. highly nonlinear and noisy), traditional approaches have their limitations. In this article, we introduced support vector regression, kriging model, and radial basis function, which are commonly used in computer experiments, into robust parameter design, and especially introduced a new strategy that builds the dual response surface using the ensemble of surrogates, which can provide a more robust approximation model. We demonstrated the advantages of kriging, support vector regression, radial basis function, and the ensemble of surrogates by reinvestigating the dual response approach on the basis of parametric, nonparametric, and semiparametric approaches, and a simulation experiment is studied. The results show that our presented models can achieve more desirable results than parametric, nonparametric, and semiparametric approaches in terms of fitting and predictive accuracy, and the optimal operating conditions recommended by our presented models are similar to those recommended in literature, which indicates the validation of our presented models. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

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针对室外智能移动机器人自主导航的要求,提出了基于多种新型视觉传感技术的室外道路环境综合理解方法,其基本原理是综合利用机器人四周360°景物的环视图象信息、机器人前方道路的双目注视图象信息以及机器人运行过程中形成的时空全景图象信息,综合完成实时机器人行驶方向确定、实时路面障碍物检测和机器人全局定位等视觉任务。  相似文献   

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一种基于实例推理的钢铁产品成本估算方法   总被引:1,自引:0,他引:1  
针对钢铁企业生产过程复杂和现有定制产品的成本估算方法存在的缺陷和不足,提出了基于实例推理技术的钢铁产品成本估算方法,分析了钢铁产品生产流程,据此认定了钢铁产品生产过程中的各项作业。详细阐述了实例库中实例的描述方法和实例库的组织结构,给出了实例匹配检索算法、实例调整和学习评价,并以在某钢铁企业的实际工程应用进行了验证说明。  相似文献   

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