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1.
数据包络分析(DEA)是评价供应链系统(Supply chain system)间相对有效性的一种重要的工具,但是传统的DEA不考虑供应链的内部结构,对系统效率评价偏高;而本文所研究两阶段串联供应链系统,考虑把部分中间产品作为最终产品输出,增加额外中间投入的情形.基于所提出的供应链系统结构,本文建立相应的串联结构下的网络DEA模型,并针对所建立模型进行相关理论的研究,给出了串联结构下的生产可能集和规模收益情况判定方法.最后,进行数值实验,以验证我们提出的结论. 相似文献
2.
Mourad Kainane Mezadek Mohamed Kainane Mezadek Michael Reissig 《Mathematical Methods in the Applied Sciences》2020,43(6):3117-3147
In this paper, we study the global (in time) existence of small data solutions to the Cauchy problem for the semilinear wave equation with friction, viscoelastic damping, and a power nonlinearity. We are interested in the connection between regularity assumptions for the data and the admissible range of exponents p in the power nonlinearity. 相似文献
3.
DFT mechanistic study of the H2‐assisted chain transfer copolymerization of propylene and p‐methylstyrene catalyzed by zirconocene complex 下载免费PDF全文
Cheng‐Gen Zhang Shu‐Yuan Yu Liaoyun Zhang Huayi Li Zhi‐Xiang Wang 《Journal of polymer science. Part A, Polymer chemistry》2015,53(4):576-585
DFT computations have been performed to investigate the mechanism of H2‐assisted chain transfer strategy to functionalize polypropylene via Zr‐catalyzed copolymerization of propylene and p‐methylstyrene (pMS). The study unveils the following: (i) propylene prefers 1,2‐insertion over 2,1‐insertion both kinetically and thermodynamically, explaining the observed 1,2‐insertion regioselectivity for propylene insertion. (ii) The 2,1‐inserion of pMS is kinetically less favorable but thermodynamically more favorable than 1,2‐insertion. The observation of 2,1‐insertion pMS at the end of polymer chain is due to thermodynamic control and that the barrier difference between the two insertion modes become smaller as the chain length becomes longer. (iii) The pMS insertion results in much higher barriers for subsequent either propylene or pMS insertion, which causes deactivation of the catalytic system. (iv) Small H2 can react with the deactivated [Zr]?pMS?PPn facilely, which displace functionalized pMS?PPn chain and regenerate [Zr]? H active catalyst to continue copolymerization. The effects of counterions are also discussed. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 576–585 相似文献
4.
Mitsuki Yamashita Yuna Kawasumi Yuki Tachibana Dr. Shinnosuke Horiuchi Dr. Koji Yamamoto Prof. Tetsuro Murahashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(5):1212-1216
Although small cyclic- and open-chain unsaturated hydrocarbon anions such as cyclopentadienide and open-chain pentadienide are used as the strongly electron-donating auxiliary ligands for metal complexes, more extended π-conjugated unsaturated hydrocarbon anions have rarely been used in coordination chemistry, despite their potential ability to serve as the multiply bridging π-ligands for metal clusters. This work reports isolation of metal chain clusters bearing the multi-dentate, open-chain extended unsaturated hydrocarbon anion ligands. The extended open-chain π-conjugated polyenyl ligands could effectively stabilize oxidized palladium chains, including an unprecedented [Pd4]4+ chain. 相似文献
5.
Non-standard fault models often require the application of two-pattern testing. A fully-automated approach for generating a multiple scan chain-based architecture is presented so that two-pattern test sets generated for the combinational core can be applied to the sequential circuit. Test time and area overhead constraints are considered. 相似文献
6.
多业务移动通信系统中的呼叫接入控制 总被引:4,自引:0,他引:4
在多业务无线移动通信系统的呼叫接入控制中,不仅要考虑业务之间的优先级,同时也必须考虑切换呼叫的优先级。本文结合可移动边界算法和保护信道策略,提出了一种有效的多业务呼叫接入控制算法。为了方便地分析方案的性能,设计了一个二维的Markov链对方案的性能进行理论上的分析。通过数值分析结果表明,提出的算法同时保证了两种优先级,并提高了系统的性能。1 相似文献
7.
Optical packet assembly is a key function to support inter-working between TCP/IP networks and optical packet-switched networks.
It is characterized by the assembly delay and by the segment aggregation needed to form an optical packet. These counter-balancing
aspects depend on several environment variables, such as the TCP parameters, the access link speed, the optical packet size
whose effects are studied in this paper. Performance evaluations are obtained by extensive simulations in terms of send rate
of TCP flows, fairness, efficiency, and assembly delay. Some guidelines in the design of optical packets that take into account
the results presented are given. 相似文献
8.
为促进互联网的良性发展,要使设备制造商、电信运营商、虚拟运营商/集团用户、内容提供商和最终用户构成一条互联网业务价值链,价值链的创建对互联网接入设备提出了更高的要求,华为公司的Quid-wayTMA8010Expert多业务综合接入平台可构建宽带城域网分组语音解决方案、可平滑演进为下一代网络中的媒体网关、提供窄带价值链、提供唯一号码业务以及实现多业务综合接入。 相似文献
9.
A profit-maximizing supply chain network design model with demand choice flexibility 总被引:1,自引:0,他引:1
Zuo-Jun Max Shen 《Operations Research Letters》2006,34(6):673-682
We present a profit-maximizing supply chain design model in which a company has flexibility in determining which customers to serve. The company may lose a customer to competition if the price it charges is too high. We show the problem formulation and solution algorithm, and discuss computational results. 相似文献
10.
利用射影几何方法在小缺陷码中,NMDS码是链条件码;给出k维NμMDS(0μk-2)码满足链条件的一个充要条件与一些易判断的充分条件. 相似文献