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112.
This paper considers a new class of multi-product source and multi-period fuzzy random production planning problems with minimum risk and service levels where both the demands and the production costs are assumed to be uncertain and characterized as fuzzy random variables with known distributions. The proposed problems are formulated as a fuzzy random production planning (FRPP) model by maximizing the mean chance of the total costs less than a given allowable investment level. Because the exact value of the objective function for a given decision variable cannot be easily obtained, we adopt an approximation approach (AA) to evaluate the objective value and then discuss the convergence of the AA, including the convergence of the objective value, the convergence of the optimal solutions and the convergence of the optimal value. Since the approximating multi-product source multi-period FRPP model is neither linear nor convex, an approximation-based hybrid monkey algorithm (MA) which combines the AA, stochastic simulation (SS), neural network (NN) and MA is designed to solve the proposed model. Finally, numerical examples are provided to illustrate the effectiveness of the hybrid monkey algorithm. 相似文献
113.
分析了质量管理信息系统的功能需求、性能需求,并据此划分了系统的核心功能模块。引入工作流技术设计了基于质量工作流的过程配置平台,结合过程方法识别质量管理信息系统的过程,设计了由应用系统和过程配置平台构成的质量管理信息系统,具体由环境层、功能层、应用逻辑层和显示层组成,并阐述了每一层次的功能。 相似文献
114.
本文从光与建筑空间一体化设计的角度出发.结合已有研究理论,从自然光环境设计和人工光环境设计两方面,探讨疗养院建筑中人性化光环境设计的积极意义,并提出相应的设计思路以供参考。 相似文献
115.
Wang Yanfei 《电子科学学刊(英文版)》1997,14(2):112-116
A new deconvolution method has been presented in this paper. Like conventional Discrete Fourier Transform(DFT) method, it is also a frequency domain method. Since there are only DFT, IDFT and multiplication calculations in the new method, the singular problem appeared in the conventional DFT method can be avoid, and the deconvolution problem can always be solved with the new method. The relationship between the presented method and conventional DFT method is discussed. A numerical example is also presented to illustrate the new method. 相似文献
116.
Visual sensing for robotics has been around for decades, but our understanding of a timing model remains crude. By timing model, we refer to the delays (processing lag and motion lag) between "reality" (when a part is sensed), through data processing (the processing of image data to determine part position and orientation), through control (the computation and initiation of robot motion), through "arrival" (when the robot reaches the commanded goal). In this study, we introduce a timing model where sensing and control operate asynchronously. We apply this model to a robotic workcell consisting of a Sta/spl uml/ubli RX-130 industrial robot manipulator, a network of six cameras for sensing, and an off-the-shelf Adept MV-19 controller. We present experiments to demonstrate how the model can be applied. 相似文献
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塔里木盆地塔中北坡奥陶系碳酸盐岩储层已成为该盆地油气勘探的重要目标之一,目前对于该岩溶储层的溶蚀机制尚存在争议。为此,基于沉积、层序与储层综合研究成果,结合微观分析测试与宏观地震资料分析结果,将该区碳酸盐岩岩溶储层划分为石灰岩溶蚀孔洞型、白云岩孔洞型和硅质岩裂缝孔洞型3种类型,并分别探讨了其形成机理。结果表明:(1)石灰岩溶蚀孔洞型储层纵向上分布在中奥陶通鹰山组上段和一间房组,而白云岩孔洞型储层主要发育在下奥陶统蓬莱坝组和鹰山组下段且厚度较大;(2)石灰岩溶蚀孔洞型储层形成于三级层序界面(低位期)岩溶作用,而白云岩孔洞型储层则主要形成于受三级层序界面岩溶作用控制的深埋藏白云石化作用,两者均分布在三级层序界面之下的高位体系域;(3)该区硅质岩储层的发育明显受断裂控制,是深部热液沿断层对石灰岩改造的结果,硅质岩储层及其热液溶蚀缝洞系统分布在断裂附近。进而推测:塔中北坡奥陶系除了发育上述3种储层类型以外,还发育台地边缘礁滩型储层。 相似文献
120.
Yujuan Sun Yanfei Lin Xueli Cao Lan Xiang Jianhua Qi 《International journal of molecular sciences》2014,15(12):21660-21673
For screening anti-aging samples from marine natural products, K6001 yeast strain was employed as a bioassay system. The active mussel extract was separated to give an active sterol fraction (SF). SF was further purified, and four sterol compounds were obtained. Their structures were determined to be cholesterol (CHOL), brassicasterol, crinosterol, and 24-methylenecholesterol. All compounds showed similar anti-aging activity. To understand the action mechanism involved, anti-oxidative experiments, reactive oxygen species (ROS) assays, and malondialdehyde (MDA) tests were performed on the most abundant compound, CHOL. Results indicated that treatment with CHOL increases the survival rate of yeast under oxidative stress and decreases ROS and MDA levels. In addition, mutations of uth1, skn7, sod1, and sod2, which feature a K6001 background, were employed and the lifespans of the mutations were not affected by CHOL. These results demonstrate that CHOL exerts anti-aging effects via anti-oxidative stress. Based on the connection between neuroprotection and anti-aging, neuroprotective experiments were performed in PC12 cells. Paraquat was used to induce oxidative stress and the results showed that the CHOL and SF protect the PC12 cells from the injury induced by paraquat. In addition, these substance exhibited nerve growth factor (NGF) mimic activities again confirmed their neuroprotective function. 相似文献