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71.
72.
Fu-Chiang Yang 《生产规划与管理》2016,27(16):1334-1343
Efficiency decomposition is being able to know the most effective way to improve a company’s organisational efficiency. This study proposes a network performance evaluation model with non-controllable variables to evaluate dealers with an emphasis on their internal processes, including demand forecasting, sales force and inventory control. The proposed model decomposes the organisational efficiency into a weighted average of internal process efficiencies, where the weights associated with the internal processes are data-driven. This is applied to an empirical case consisting of 27 automobile parts dealers in Taiwan. Based on the analysis results, dealers know the relative contribution of each internal process to the organisational efficiency, and inefficient dealers are assigned targets for enhancing the organisational efficiency as well as the process efficiencies. 相似文献
73.
目的:研究丁酸钠(sodium butyrate,BTR)对大鼠肠缺血/再灌注(ischemia-reperfusion,I/R)后小肠损伤的保护作用.方法:♂SD大鼠50只,随机分为假手术组(sham组),肠I/R 1 h组和4 h组(I/R1组和I/R4组),BTR干预1 h组和4 h组(BTR1组和BTR4组),每组10只.丁酸钠组和肠I/R组夹闭大鼠肠系膜上动脉30 min,恢复灌流后观察4 h,制备肠I/R模型;假手术组仅开腹不夹闭动脉.BTR组于术后立即行皮下注射BTR(400mg/kg),假手术组和肠I/R组皮下注射等量生理盐水.于I/R 1 h和4 h后,测定小肠黏膜血流量,取血浆检测血浆肿瘤坏死因子(tumor necrosis factor-α,TNF-α)水平和二胺氧化酶(diamine oxidase,DAO)活性,取小肠组织检测髓过氧化物酶(myeloperoxidase,MPO)、脂质过氧化物丙二醛(malondialdehyde,M D A)活性和血管内皮生长因子(v a s c u l a r endothelial growth factor,VEGF)含量,检测小肠微血管通透性和含水率,HE染色观察小肠病理变化.结果:肠I/R致小肠损伤组血浆T N F-α、D A O及小肠组织含水率、微血管通透性、M D A、M P O、V E G F明显高于假手术组(P<0.05),小肠黏膜血流量明显降低(P<0.05),小肠损伤明显.与对应时间点I/R组相比,B T R治疗后血浆T N F-α、D A O及小肠组织含水率、微血管通透性、MDA、MPO、VEGF明显降低(P<0.05),小肠黏膜血流量升高(P<0.05),小肠损伤减轻.结论:BTR减轻大鼠肠I/R后小肠微血管通透性、组织水肿,增高小肠黏膜血流量,具有一定的小肠保护作用.其保护机制与清除氧自由基,减轻炎症反应和降低小肠VEGF表达有关. 相似文献
74.
A \(k\)-connected (resp. \(k\)-edge connected) dominating set \(D\) of a connected graph \(G\) is a subset of \(V(G)\) such that \(G[D]\) is \(k\)-connected (resp. \(k\)-edge connected) and each \(v\in V(G)\backslash D\) has at least one neighbor in \(D\). The \(k\) -connected domination number (resp. \(k\) -edge connected domination number) of a graph \(G\) is the minimum size of a \(k\)-connected (resp. \(k\)-edge connected) dominating set of \(G\), and denoted by \(\gamma _k(G)\) (resp. \(\gamma '_k(G)\)). In this paper, we investigate the relation of independence number and 2-connected (resp. 2-edge-connected) domination number, and prove that for a graph \(G\), if it is \(2\)-edge connected, then \(\gamma '_2(G)\le 4\alpha (G)-1\), and it is \(2\)-connected, then \(\gamma _2(G)\le 6\alpha (G)-3\), where \(\alpha (G)\) is the independent number of \(G\). 相似文献
75.
结合实际企业ERP系统实施过程中咨询与监理的经验,讨论了ERP项目咨询与监理及其融合的必要性、特点和运作规律. 相似文献
76.
One of today's most frequently discussed topics in the business world is how to escape from the intense Red Ocean and how to create an uncontested Blue Ocean. However, because there are few practical guidelines available on this topic, we will introduce a case study of a third-party logistics (3PL) provider, CJ-Global Logistics Service (CJ-GLS), to show how it aspires to be a leader in the newly introduced 3PL industry in South Korea. CJ-GLS is a latecomer in the logistics industry, and its resources, such as the number of trucks and warehouses, are relatively small in comparison to those of established companies. But, it has achieved a distinct competitive advantage through innovative information technology (i.e., RFID—radio frequency identification), which has enabled it to create an uncontested market space, electronic logistics business. One remarkable fact about CJ-GLS is that its swift growth comes not from attracting competitors’ customers from the existing Red Ocean market but from creating a Blue Ocean market (3PL market), which previously existing incumbents ignored, and also from constructing a new business model founded on a RFID-based, ubiquitous-oriented 3PL system. Analyzed through a Four Actions Framework and characterized as Blue Ocean, this case study provides valuable information on how a company reinforces its competitive advantage from the Red Ocean while it transitions into a Blue Ocean by utilizing advanced information communication technologies. 相似文献
77.
Reliability is a very important issue in Mobile Ad hoc NETworks (MANETs). Shortest paths are usually used to route packets
in MANETs. However, a shortest path may fail quickly, because some of the wireless links along a shortest path may be broken
shortly after the path is established due to mobility of mobile nodes. Rediscovering routes may result in substantial data
loss and message exchange overhead. In this paper, we study reliable ad hoc routing in the urban environment. Specifically,
we formulate and study two optimization problems. In the minimum Cost Duration-bounded Path (CDP) routing problem, we seek
a minimum cost source to destination path with duration no less than a given threshold. In the maximum Duration Cost-bounded
Path (DCP) routing problem, we seek a maximum duration source to destination path with cost no greater than a given threshold.
We use a waypoint graph to model the working area of a MANET and present an offline algorithm to compute a duration prediction
table for the given waypoint graph. An entry in the duration prediction table contains the guaranteed worst-case duration
of the corresponding wireless link. We then present an efficient algorithm which computes a minimum cost duration-bounded
path, using the information provided in the duration prediction table. We also present a heuristic algorithm for the DCP routing
problem. In addition, we show that the proposed prediction and routing schemes can be easily applied for designing reliable
ad hoc routing protocols. Simulation results show that our mobility prediction based routing algorithms lead to higher network
throughput and longer average path duration, compared with the shortest path routing.
This research was supported in part by ARO grant W911NF-04-1-0385 and NSF grant CCF-0431167. The information reported here
does not reflect the position or the policy of the federal government. 相似文献
78.
与组织融为一体并相互作用的具有动态结构的开放信息系统是国民经济信息化的基础。本文抽象出信息系统动态运行的需求控制结构,提出了保证这种反馈结构的计算机信息系统的建设要求。 相似文献
79.
本文以机械企业为背景,探讨了一人多机看管问题中的人员配置问题,并采用层次序列法对人员配置数学模型进行了求解,给出了启发式解法,指出了进一步研究的方向。 相似文献
80.
The 2-INTERVAL PATTERN problem is to find the largest constrained pattern in a set of 2-intervals. The constrained pattern
is a subset of the given 2-intervals such that any pair of them are R-comparable, where model . The problem stems from the study of general representation of RNA secondary structures. In this paper, we give three improved
algorithms for different models. Firstly, an O(n{log} n +L) algorithm is proposed for the case , where is the total length of all 2-intervals (density d is the maximum number of 2-intervals over any point). This improves previous O(n
2log n) algorithm. Secondly, we use dynamic programming techniques to obtain an O(nlog n + dn) algorithm for the case R = { <, ⊏ }, which improves previous O(n
2) result. Finally, we present another algorithm for the case with disjoint support(interval ground set), which improves previous O(n
2□n) upper bound.
A preliminary version of this article appears in Proceedings of the 16th Annual International Symposium on Algorithms and
Computation, Springer LNCS, Vol. 3827, pp. 412–421, Hainan, China, December 19–21, 2005. 相似文献