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11.
多因素评审法就是建立一个相对客观的评审模型,将商务报价与技术评审有机地结合起来,使无形的标准数量化,并逐一比较投标商的综合实力。采用此法有利于业主选取理想的投标商。  相似文献   
12.
We report a rapid, highly sensitive microarray method for quantitative aflatoxin B1 (AFB1) detection in cereal samples. Following optimisation using an indirect competitive immunoassay, optimised amounts of AFB1-bovine serum albumin (AFB1-BSA)-conjugate were contact-printed onto 16 isolated sub-arrays on multi-pad nitrocellulose coated slides subsequently used in competitive binding assays.The toxin microarray working range for AFB1 was established in the range of 15 pg g−1 to 3.04 ng g−1, with a detection limit of 1 pg g−1. To determine assay sensitivity in contaminated food models, wheat flour and barley grains samples were spiked with AFB1 standard dilutions. Following extraction, the working ranges of 0.11–4.15 and 0.18–4.31 ng g−1 were determined, with detection limits of 30 and 90 pg g−1, respectively. The sensitivity of the developed assay is below the European commission limit set for AFB1 detection and the assay procedure was completed in 3 h time. Good recoveries (98% ± 11%) obtained demonstrate the suitability of the proposed method for rapid and sensitive quantification of AFB1 in contaminated cereal samples.  相似文献   
13.
We consider the online scheduling of a set of jobs on two uniform machines with the makespan as objective. The jobs are presented in a list. We consider two different eligibility constraint set assumptions, namely (i) arbitrary eligibility constraints and (ii) Grade of Service (GoS) eligibility constraints. In the first case, we prove that the High Speed Machine First (HSF) algorithm, which assigns jobs to the eligible machine that has the highest speed, is optimal. With regard to the second case, we point out an error in [M. Liu et al., Online scheduling on two uniform machines to minimize the makespan, Theoretical Computer Science 410 (21–23) (2009) 2099–2109]; we then provide tighter lower bounds and present algorithms with worst-case analysis for various ranges of machine speeds.  相似文献   
14.
In this paper, we consider the following question: what is the worst possible page-replacement strategy? Our goal is to devise an online strategy that has the highest possible fraction of page faults as compared to the worst offline strategy. We show that there is no deterministic, online page-replacement strategy that is competitive with the worst offline strategy. We give a randomized strategy based on the “most-recently-used” heuristic and show that this strategy is the worst possible online page-replacement strategy.  相似文献   
15.
Amol Phadke   《Energy》2009,34(11):1917-1924
I analyze the determinants of the stated capital cost of IPPs' power projects which significantly influences their price of power. I show that IPPs face a strong incentive to overstate their capital cost and argue that effective competition or regulatory scrutiny will limit the extent of the same. I analyze the stated capital costs of combined cycle gas turbine (CCGT) IPP projects in eight developing countries which became operational during 1990–2006 and find that the stated capital cost of projects selected without competitive bidding is 44–56% higher than those selected with competitive bidding, even after controlling for the effect of cost differences among projects. The extent to which the stated capital costs of projects selected without competitive bidding are higher compared those selected with competitive bidding, is a lower bound on the extent to which they are overstated. My results indicate the drawbacks associated with a policy of promoting private sector participation without an adequate focus on improving competition or regulation.  相似文献   
16.
We study online scheduling on two unbounded parallel-batching machines with limited restarts to minimize the makespan. In this system jobs arrive over time and a batch can be restarted if and only if all the jobs in it have never been restarted. To tackle this difficult problem, we make the second-restart assumption whereby we can only interrupt a running batch B at time t if both machines are busy at time t and batch B has a later starting time than the other running batch. For this case, we provide a best online algorithm with a competitive ratio . For the general problem, we show that no online algorithms can have a competitive ratio less than 1.298, leaving a gap from 1.298 to 1.366.  相似文献   
17.
提出了将自组织竞争人工神经网络(SCNN)和小波矩结合进行图像旋转不变识别的新方法。SCNN可以克服反向传播神经网络(BPN)不易收敛、低效率等缺点,而且小波矩方法提取的图像不变矩特征具有很强的辨别力和抗噪性能。计算机模拟显示该方法使用简单、效率高,具有很好的研究价值。  相似文献   
18.
基于竞争神经网络的中医智能诊断推理新方法   总被引:5,自引:0,他引:5  
文章通过融合模糊逻辑推理、神经网络技术及可拓学方法,研究了一种基于竞争神经网络的智能推理模型,实现了对中医专家诊断推理过程的模拟。在复杂的亚健康状态中医诊断推理过程中的应用结果表明,该文研究的智能推理模型可以较好地应用于中医辨证。  相似文献   
19.
Exploring a polygon with robots when the robots do not have knowledge of the surroundings can be viewed as an online problem. Typical for online problems is that decisions must be made based on past events without complete information about the future. In our case the robots do not have complete information about the environment. Competitive analysis can be used to measure the performance of methods solving online problems. The competitive ratio of such a method is the ratio between the method's performance and the performance of the best method having full knowledge of the future. We prove constant competitive strategies and lower bounds for exploring a simple rectilinear polygon in the L1L1 metric.  相似文献   
20.
谈竞争情报与企业竞争   总被引:3,自引:0,他引:3  
本文分析了竞争情报的内涵及其在企业发展和市场竞争中的战略地位与作用,研究了企业竞争情报的收集渠道与收集方法,并就如何加强与改善我国企业的竞争情报工作进行了初步探讨。  相似文献   
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