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排序方式: 共有1308条查询结果,搜索用时 31 毫秒
21.
信息网络技术的不断发展使网购逐渐成为人们购买物品的方式之一,但是网上信息的真实与否也带来了购物烦恼.通过调查问卷和已有文献,分析了消费者在商家对顾客模式(B2C)网站上购物时主要考虑的影响因素指标,用模糊层次分析(Fuzzy-AHP)法对这些指标进行了评价分析,从而把模糊的信息指标量化.研究结果以直观的评价结果为消费者网购提供了参考.  相似文献   
22.
文劲松  罗清泉 《贵金属》2006,27(4):56-60
作者采用高频红外吸收法同时测定Ag中的C和S,对试样的制备、助熔剂的选择、分析条件等进行了较详细的研究.方法快速、简便、灵敏度高,C、S的测定范围分别为0.002%~1%和0.002%~0.1%,对自己配制的合成样进行6次平行测定,其RSD分别为:C = 0.34%和S = 2.01%,C、S的回收率都在95%~105%,获得了满意的结果.  相似文献   
23.
针对传统模糊综合评价法具有评价指标权重矢量的确定主观性强、相对隶属度权系数易偏小、不能全面反映水库健康状态等缺陷,本文旨在优化水库健康评价方法,围绕水库健康评价指标体系,应用AHP、EWM、AHP-EWM、AHP-Cloud、AHP-EWM-Cloud共五种赋权方法进行权重分析比较。通过闵式距离确定最佳赋权方法,并以云模型确定隶属度函数,建立基于改进云模型的模糊综合评价模型对汾河二库进行健康评价。AHP-EWM-Cloud法被确定为用于汾河二库工程案例分析的最佳赋权法,水库整体评价等级为健康,但岸坡稳定与水质情况仍需改进。该结果与水库实际情况相符,验证了该方法的合理性与可行性。研究表明:基于AHP-EWM-Cloud法的改进云模型兼顾了数据的客观存在、决策者的主观意识以及模糊性与随机性,为水库健康评价提供了一种可行的新思路。  相似文献   
24.
Numerous companies are expecting their knowledge management (KM) to be performed effectively in order to leverage and transform the knowledge into competitive advantages. However, here raises a critical issue of how companies can better evaluate and select a favorable KM strategy prior to a successful KM implementation. The KM strategy selection is a kind of multiple criteria decision-making (MCDM) problem, which requires considering a large number of complex factors as multiple evaluation criteria. A robust MCDM method should consider the interactions among criteria. The analytic network process (ANP) is a relatively new MCDM method which can deal with all kinds of interactions systematically. Moreover, the Decision Making Trial and Evaluation Laboratory (DEMATEL) not only can convert the relations between cause and effect of criteria into a visual structural model, but also can be used as a way to handle the inner dependences within a set of criteria. Hence, this paper proposes an effective solution based on a combined ANP and DEMATEL approach to help companies that need to evaluate and select KM strategies. Additionally, an empirical study is presented to illustrate the application of the proposed method.  相似文献   
25.
Manufacturing systems produce their products by making use of three main strategies: make-to-order, make-to-stock and hybrid (combination of MTO and MTS strategies) systems. Hence, several products must be considered and partitioned in terms of many different conflicting criteria, leading to a large set of subjective or ambiguous data. Thus, an effective evaluation approach is essential to improve decision quality. In this paper a comprehensive decision, making structure is proposed to choose the proper strategy for producing the products. It consists of a novel hybrid methodology, which combines analytical hierarchy process (AHP) and technique for order performance by similarity to ideal solution (TOPSIS) for partitioning of products. In this study, the rating of each alternative regarding different criteria (throughout the TOPSIS technique) is described by means of linguistic variables. Furthermore, fuzzy AHP methodology is applied to determine the weights of evaluation criteria. At the end, the effectiveness of the proposed model is demonstrated through a case study.  相似文献   
26.
周文康  王行甫 《计算机工程》2022,48(3):131-138+161
无线传感器网络(WSN)由许多传感器节点组成,这些传感器节点为了降低能量消耗会周期性地在醒与睡2种模式下进行切换。在异步WSN中,发送节点往往要等接收节点醒来才能进行数据转发,为了缩短该等待时延,发送节点选择多个节点作为候选转发节点,由于任何候选转发节点都有可能进行数据路由,使得邻居节点评估和候选转发节点选择对网络性能产生较大影响。为了更好地进行节点评估与选择,提出一种基于层次分析法(AHP)和模糊推理系统(FIS)的WSN路由算法DAF。将剩余能量、距离和角度作为评估准则,利用AHP确定评估准则的权重,通过FIS动态构建AHP中的成对比较矩阵,并根据该矩阵动态计算出邻居节点的评分,按评分高低选择候选转发节点。实验结果表明,在改变节点数量、睡眠时长和通信半径的对比测试中,DAF在生命周期、能量消耗和平均冗余传输性能方面均优于ORW和ORR算法。  相似文献   
27.
We propose a novel sequence alignment algorithm for recognizing handwriting gestures by a camera. In the proposed method, an input image sequence is aligned to the reference sequences by phase-synchronization of analytic signals which are transformed from original feature values. A cumulative distance is calculated simultaneously with the alignment process, and then used for the classification. A major benefit of this method is that over-fitting to sequences of incorrect categories is restricted. The proposed method exhibited higher recognition accuracy in handwriting gesture recognition, compared with the conventional dynamic time warping method which explores optimal alignment results for all categories.  相似文献   
28.
为了解决企业战略目标执行难的问题,提升绩效评估合理性。笔者在深入研究现存理论和方法的基础上,采用平衡记分卡理论从企业战略目标中提取关键评估指标,并提出了用分解矩阵的方法将评估指标分解到各评估对象。最后引用层次分析法确定各指标权重。建立了引导、鼓励员工工作向有利于企业战略的执行与控制的绩效评估指标体系和评价模型。开发的系统在某印刷企业得到应用并取得良好效果,有效证明了模型的可行性和科学性。  相似文献   
29.
We present a second-order analytic solution to the nonlinear depth-integrated shallow water equations for free-surface oscillatory wind-driven flow in an idealized lake. Expressing the solution as an asymptotic expansion in the dimensionless wave amplitude (ζ/h), which is considered to be a small parameter, enables simplification of the governing equations and permits the use of a perturbation approach to solve them.This analytic solution provides a benchmark for testing numerical models. In particular, the main merit of this solution is that it accounts for advective effects, which are typically omitted from analytic solutions of two-dimensional free surface flow. In order to retain these effects in an analytic solution, we restrict our attention to forcing from a monochromatic wind stress, consider a constant depth rectangular lake, and simplify the governing equations by omitting the Coriolis and eddy viscosity terms and using a linearised friction factor. As such, the analytic solution is of limited use for considering real world problems. Due to the complexity of the analytic solution computer code for this solution is available online.Our solution is valid for cases where changes in the water surface level are small compared with the depth of the lake, and the advective terms in the momentum equations are small compared with acceleration terms. We examine the validity of these assumptions for three test cases, and compare the second-order analytic solution to numerical results to verify an existing hydrodynamic model.  相似文献   
30.
Product-service system (PSS) approach has emerged as a competitive strategy to impel manufacturers to offer a set of product and services as a whole. A three-domain PSS conceptual design framework based on quality function deployment (QFD) is proposed in this research. QFD is a widely used design tool considering customer requirements (CRs). Since both product and services influence satisfaction of customer, they should be designed simultaneously. Identification of the critical parameters in these domains plays an important role. Engineering characteristics (ECs) in the functional domain include product-related ECs (P-ECs) and service-related ECs (S-ECs). ECs are identified by translating customer requirements (CRs) in the customer domain. Rating ECs’ importance has a great impact on achieving an optimal PSS planning. The rating problem should consider not only the requirements of customer, but also the requirements of manufacturer. From the requirements of customer, the analytic network process (ANP) approach is integrated in QFD to determine the initial importance weights of ECs considering the complex dependency relationships between and within CRs, P-ECs and S-ECs. In order to deal with the vagueness, uncertainty and diversity in decision-making, the fuzzy set theory and group decision-making technique are used in the super-matrix approach of ANP. From the requirements of manufacturer, the data envelopment analysis (DEA) approach is applied to adjust the initial weights of ECs taking into account business competition and implementation difficulty. A case study is carried out to demonstrate the effectiveness of the developed integrated approach for prioritizing ECs in PSS conceptual design.  相似文献   
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