最优化生产技术(Optimized Production Technology,OPT)是一种全新的生产管理方法,其根据是一个简单的概念:生产最大化未必是利润最大化的最佳途径。OPT于七十年代出现在以色列,随后很快被移植到美国。目前,美国有20多家大公司采用了以...最优化生产技术(Optimized Production Technology,OPT)是一种全新的生产管理方法,其根据是一个简单的概念:生产最大化未必是利润最大化的最佳途径。OPT于七十年代出现在以色列,随后很快被移植到美国。目前,美国有20多家大公司采用了以OPT为基础的生产管理制度。OPT的内容主要有以下三点: 1.最大限度地挖掘“瓶颈”的潜力。所谓“展开更多
针对当前在制品库存控制研究较少考虑系统瓶颈的现状,从最优化生产技术(Optimized Production Technology,OPT)的思想出发,在辨别出系统瓶颈的基础上,设计以瓶颈为中心驱动的推、拉结合(Push&Pull)的生产控制方式,以有效减少整个系...针对当前在制品库存控制研究较少考虑系统瓶颈的现状,从最优化生产技术(Optimized Production Technology,OPT)的思想出发,在辨别出系统瓶颈的基础上,设计以瓶颈为中心驱动的推、拉结合(Push&Pull)的生产控制方式,以有效减少整个系统的在制品库存;建立面向瓶颈的在制品库存前-反馈集成控制(B-WFFIC)模型,稳定并减少瓶颈工序前的在制品库存;最后通过实例应用和仿真验证取得了较优的结果。展开更多
Cytosine-substituted mildiomycin analogue (MIL-C) was produced effectively by supplementing cytosine into the culture of Streptoverticillium rimofaciens. In order to improve the yield of MIL-C, statistically-based e...Cytosine-substituted mildiomycin analogue (MIL-C) was produced effectively by supplementing cytosine into the culture of Streptoverticillium rimofaciens. In order to improve the yield of MIL-C, statistically-based experimental designs were applied to optimize the fermentation medium for S. rimofaciens ZJU 5119. Fifteen culture conditions were examined for their significances on MIL-C production using Plackett-Burman design. The Plackett-Burrnan design and one-variable-at-a-time design indicated that glucose and rice meal as the complex carbon sources, and peanut cake meal and NH4NO3 as the complex nitrogen sources were beneficial for MIL-C production in S. rimofaciens ZJU 5119. The results of further central composition design (CCD) showed that the optimal concentration of glucose, rice meal and peanut cake meal were 18.7 g/L, 64.8 g/L and 65.1 g/L, respectively. By using this optimal fermentation medium, the MIL-C concentration was increased up to 1336.5 mg/L, an approximate 3.8-fold improvement over the previous concentration (350.0 mg/L) with un-optimized medium. This work will be very helpful to the large-scale production of MIL-C in the future.展开更多
A conduction heat transfer process is enhanced by filling prescribed quantity and optimized-shaped high thermal conductivity materials to the substrate. Numerical simulations and analyses are performed on a volume to ...A conduction heat transfer process is enhanced by filling prescribed quantity and optimized-shaped high thermal conductivity materials to the substrate. Numerical simulations and analyses are performed on a volume to point conduction problem based on the principle of minimum entropy generation. In the optimization, the arrangement of high thermal conductivity materials is variable, the quantity of high thermal-conductivity material is constrained, and the objective is to obtain the maximum heat conduction rate as the entropy is the minimum.A novel algorithm of thermal conductivity discretization is proposed based on large quantity of calculations.Compared with other algorithms in literature, the average temperature in the substrate by the new algorithm is lower, while the highest temperature in the substrate is in a reasonable range. Thus the new algorithm is feasible. The optimization of volume to point heat conduction is carried out in a rectangular model with radiation boundary condition and constant surface temperature boundary condition. The results demonstrate that the algorithm of thermal conductivity discretization is applicable for volume to point heat conduction problems.展开更多
文摘最优化生产技术(Optimized Production Technology,OPT)是一种全新的生产管理方法,其根据是一个简单的概念:生产最大化未必是利润最大化的最佳途径。OPT于七十年代出现在以色列,随后很快被移植到美国。目前,美国有20多家大公司采用了以OPT为基础的生产管理制度。OPT的内容主要有以下三点: 1.最大限度地挖掘“瓶颈”的潜力。所谓“
文摘针对当前在制品库存控制研究较少考虑系统瓶颈的现状,从最优化生产技术(Optimized Production Technology,OPT)的思想出发,在辨别出系统瓶颈的基础上,设计以瓶颈为中心驱动的推、拉结合(Push&Pull)的生产控制方式,以有效减少整个系统的在制品库存;建立面向瓶颈的在制品库存前-反馈集成控制(B-WFFIC)模型,稳定并减少瓶颈工序前的在制品库存;最后通过实例应用和仿真验证取得了较优的结果。
基金Project supported by the Ministry of Science and Technology, China (No. 2004BA308A22-14)the Department of Science and Tech- nology of Zhejiang Province, China (No. 011102543)
文摘Cytosine-substituted mildiomycin analogue (MIL-C) was produced effectively by supplementing cytosine into the culture of Streptoverticillium rimofaciens. In order to improve the yield of MIL-C, statistically-based experimental designs were applied to optimize the fermentation medium for S. rimofaciens ZJU 5119. Fifteen culture conditions were examined for their significances on MIL-C production using Plackett-Burman design. The Plackett-Burrnan design and one-variable-at-a-time design indicated that glucose and rice meal as the complex carbon sources, and peanut cake meal and NH4NO3 as the complex nitrogen sources were beneficial for MIL-C production in S. rimofaciens ZJU 5119. The results of further central composition design (CCD) showed that the optimal concentration of glucose, rice meal and peanut cake meal were 18.7 g/L, 64.8 g/L and 65.1 g/L, respectively. By using this optimal fermentation medium, the MIL-C concentration was increased up to 1336.5 mg/L, an approximate 3.8-fold improvement over the previous concentration (350.0 mg/L) with un-optimized medium. This work will be very helpful to the large-scale production of MIL-C in the future.
基金Supported by the National Key Basic Research Program of China(2013CB228305)
文摘A conduction heat transfer process is enhanced by filling prescribed quantity and optimized-shaped high thermal conductivity materials to the substrate. Numerical simulations and analyses are performed on a volume to point conduction problem based on the principle of minimum entropy generation. In the optimization, the arrangement of high thermal conductivity materials is variable, the quantity of high thermal-conductivity material is constrained, and the objective is to obtain the maximum heat conduction rate as the entropy is the minimum.A novel algorithm of thermal conductivity discretization is proposed based on large quantity of calculations.Compared with other algorithms in literature, the average temperature in the substrate by the new algorithm is lower, while the highest temperature in the substrate is in a reasonable range. Thus the new algorithm is feasible. The optimization of volume to point heat conduction is carried out in a rectangular model with radiation boundary condition and constant surface temperature boundary condition. The results demonstrate that the algorithm of thermal conductivity discretization is applicable for volume to point heat conduction problems.