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Financing Model Decision of Inter-basin Water Transfer Projects

Ji-wei Zhu,Li-nan Zhou,Zhao Zhai,Cong Wang

《工程管理前沿（英文）》 2016年第3卷第4期页码 396-403 doi: 10.15302/J-FEM-2016060

摘要： Inter-basin Water Transfer Projects require the appropriate financing model to attract large amounts of social investment. Therefore, financing model decision becomes the key of engineering construction. In three aspects, such as the subject, the object and the target of the financing model, Grey Target Model is established in this paper. First, the complex financing mode decision problems of Inter-basin Water Transfer Projects are decomposed by using hierarchical decomposition method. Then Analytical Hierarchy Process (AHP) method is used to calculate the comprehensive weight of evaluation index. Experts’ opinions financing model are transformed into the evaluation matrix based on the Dephi method. The Weighted Grey Target Model is used to calculate the approaching degree of financing model and assists financing mode decision. In addition, this paper takes the water diversion project from the Han to the Wei River of Shaanxi Province as a verification example for the model. For other water diversion projects, the evaluation results are also reliable and provide theoretical references for the financing model decision of Inter-basin Water Transfer Projects.

关键词： Inter-basin Water Transfer Projects financing model Weighted Grey Target Model water diversion Han River Wei River

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基于区间数的多指标灰靶决策模型的研究

党耀国,刘思峰,刘斌

《中国工程科学》 2005年第7卷第8期页码 31-35

摘要：

现实生活中遇到的许多问题都具有不确定性，使得在对系统进行决策评估时，指标值难以精确化。在此情形下，人们常常对指标值给出一个区间，到目前为止，尚未有人研究区间数灰靶决策。首先定义了区间数、m维区间数的距离及其距离性质，并证明了当区间数为实数时，区间数距离就是实数距离的推广；提出了区间数规范化方法，在此基础上, 建立了基于区间数的灰靶决策模型，从而把灰靶决策模型由实数序列拓展到区间数序列，使灰靶决策理论得到发展，同时为扩大灰靶决策的应用领域提供了理论根据。最后以实例验证了该模型的有效性与实用性。

关键词：区间数灰靶决策模型应用

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火灾事故的灰色-马尔可夫模型预测研究

毛占利,朱毅,杨伯忠,朱磊

《中国工程科学》 2010年第12卷第1期页码 98-101

摘要：

鉴于火灾事故的发生受多种复杂因素的影响，并且具有较大的随机性和波动性的特点，笔者等将灰色模型和马尔可夫模型相结合，建立火灾事故的灰色–马尔可夫模型，利用灰色模型的灰色性和马尔可夫模型的随机性来体现各自的优点，并运用该模型对全国农村火灾事故进行预测。实际应用表明，灰色–马尔可夫模型的预测精度明显高于灰色模型的预测精度，完全能满足预测精度的要求，可以较好地用于火灾事故的预测。

关键词：灰色模型马尔可夫模型火灾事故预测

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区间灰数表征与算法改进及其GM(1,1)模型应用研究

方志耕,刘思峰,陆芳,万军,刘斌

《中国工程科学》 2005年第7卷第2期页码 57-61

摘要：

针对目前区间灰数的表征和运算过程中存在着较为严重的问题，即：运算结果对灰数的灰度进行不必要的放大，造成信息的严重失真，笔者定义了标准区间灰数与第一和第二标准区间灰数的概念，分析了第一和第二标准区间灰数之间的关系，进一步设计了普通区间灰数与标准区间灰数之间的转换规则，提供了标准区间灰数之间的比较与运算法则，较好地解决了区间灰数之间的大小比较与运算问题。最后，将这一研究成果应用于基于区间数的GM (1, 1)模型预测问题，取得了良好的效果。

关键词：区间灰数标准区间灰数表征 GM(1 1)模型运算规则

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基于动态多指标灰色关联决策模型的研究

党耀国,刘思峰,刘斌,陶勇

《中国工程科学》 2005年第7卷第2期页码 69-72

摘要：

针对动态多指标系统的决策特点，对指标数据初始化处理时，利用“奖优罚劣”原则，提出了一种易于计算且实用的［-1，1］线性变换算子，用此方法寻求各时段的正、负理想方案，建立一种新的基于动态多指标灰色关联分析决策模型，在模型中充分考虑了各指标在系统中的成长特性，将此特性用于灰色关联分析，为动态多目标决策问题提供了一种科学、实用的方法，并利用现有的实例来证实此方法的科学性与可行性。

关键词：灰色关联分析多指标决策模型

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radiation fraction induced by interaction burning of tri-symmetric propane fires in open space based on weightedmulti-point source model

Jie JI, Junrui DUAN, Huaxian WAN

《能源前沿（英文）》 2022年第16卷第6期页码 1017-1026 doi: 10.1007/s11708-020-0716-x

摘要： The interaction of multiple fires may lead to a higher flame height and more intense radiation flux than a single fire, which increases the possibility of flame spread and risks to the surroundings. Experiments were conducted using three burners with identical heat release rates (HRRs) and propane as the fuel at various spacings. The results show that flames change from non-merging to merging as the spacing decreases, which result in a complex evolution of flame height and merging point height. To facilitate the analysis, a novel merging criterion based on the dimensionless spacing / was proposed. For non-merging flames ( / >0.368), the flame height is almost identical to a single fire; for merging flames ( / ≤0.368), based on the relationship between thermal buoyancy and thrust (the pressure difference between the inside and outside of the flame), a quantitative analysis of the flame height, merging point height, and air entrainment was formed, and the calculated merging flame heights show a good agreement with the measured experimental values. Moreover, the multi-point source model was further improved, and radiation fraction of propane was calculated. The data obtained in this study would play an important role in calculating the external radiation of propane fire.

关键词： flame interaction air entrainment flame height multi-point source model thermal radiation

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灰色模型GM(1,1)优化

罗党,刘思峰,党耀国

《中国工程科学》 2003年第5卷第8期页码 50-53

摘要：

分析了GM（1，1）模型产生模拟误差的原因，经大量的数据模拟和GM（1，1）模型比较，发现背景值的优化使GM（1，1）模型在短期、中期及长期预测中扩大了适用范围，并且模拟及预测精度显著提高。

关键词： GM（1，1）模型白化方程背景值

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Regional wind power forecasting model with NWP grid data optimized

Zhao WANG, Weisheng WANG, Bo WANG

《能源前沿（英文）》 2017年第11卷第2期页码 175-183 doi: 10.1007/s11708-017-0471-9

摘要： Unlike the traditional fossil energy, wind, as the clean renewable energy, can reduce the emission of the greenhouse gas. To take full advantage of the environmental benefits of wind energy, wind power forecasting has to be studied to overcome the troubles brought by the variable nature of wind. Power forecasting for regional wind farm groups is the problem that many power system operators care about. The high-dimensional feature sets with redundant information are frequently encountered when dealing with this problem. In this paper, two kinds of feature set construction methods are proposed which can achieve the proper feature set either by selecting the subsets or by transforming the original variables with specific combinations. The former method selects the subset according to the criterion of minimal-redundancy-maximal-relevance (mRMR), while the latter does so based on the method of principal component analysis (PCA). A locally weighted learning method is also proposed to utilize the processed feature set to produce the power forecast results. The proposed model is simple and easy to use with parameters optimized automatically. Finally, a case study of 28 wind farms in East China is provided to verify the effectiveness of the proposed method.

关键词： regional wind power forecasting feature set minimal-redundancy-maximal-relevance (mRMR) principal component analysis (PCA) locally weighted learning model

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灰数灰度的一种公理化定义

刘思峰,林益

《中国工程科学》 2004年第6卷第8期页码 91-94

摘要：

基于对已有的几种灰数灰度定义的讨论，建立了灰数灰度定义的公理系统；以灰数灰度定义公理为准绳，由灰数产生的背景或论域及灰数取数域的测度构造出一种新的灰数灰度定义式。新定义克服了原有定义中存在的问题，较为科学地描述了灰数的不确定程度。

关键词：灰色系统灰数灰度测度公理化定义

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Amodified variable rate particle filter for maneuvering target tracking

Yun-fei GUO,Kong-shuai FAN,Dong-liang PENG,Ji-an LUO,Han SHENTU

《信息与电子工程前沿（英文）》 2015年第16卷第11期页码 985-994 doi: 10.1631/FITEE.1500149

摘要： To address the problem of maneuvering target tracking, where the target trajectory has prolonged smooth regions and abrupt maneuvering regions, a modified variable rate particle filter (MVRPF) is proposed. First, a Cartesian-coordinate based variable rate model is presented. Compared with conventional variable rate models, the proposed model does not need any prior knowledge of target mass or external forces. Consequently, it is more convenient in practical tracking applications. Second, a maneuvering detection strategy is adopted to adaptively adjust the parameters in MVRPF, which helps allocate more state points at high maneuver regions and fewer at smooth regions. Third, in the presence of small measurement errors, the unscented particle filter, which is embedded in MVRPF, can move more particles into regions of high likelihood and hence can improve the tracking performance. Simulation results illustrate the effectiveness of the proposed method.

关键词： Maneuvering target tracking Prolonged smooth regions Variable rate model Maneuver detection

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evaluation of renal function using diffusion weighted imaging and diffusion tensor imaging in type 2

null

《医学前沿（英文）》 2014年第8卷第4期页码 471-476 doi: 10.1007/s11684-014-0365-8

摘要：

This work aims to estimate the value of diffusion weighted imaging (DWI) and diffusion tensor imaging (DTI) in detecting early-stage kidney injury in type 2 diabetic patients with normoalbuminuria (NAU) versus microalbuminuria (MAU) prospectively. A total of 30 T2DM patients with normal kidney function were recruited and assigned to the NAU group (n = 14) or MAU group (n= 16) according to 8 h overnight urinary albuminuria excretion rate (AER) results. A contemporary cohort of health check-up recipients were included as controls (n = 12). DWI and DTI scans were performed on bilateral kidney using SE single-shot EPI, and apparent diffusion coefficient (ADC) and fractional anisotropy (FA) of the renal parenchyma was determined from ADC and FA maps of the three groups. ADC and FA values were compared among the three groups. According to DWI with a b value of 400 s/mm², the MAU and NAU groups showed significantly lowered mean ADC values compared with the healthy controls (P<0.01). The mean ADC in the MAU group [(2.22±0.07)×10^–3 mm²/s] was slightly lower than that of the NAU group [(2.31±0.22)×10^–3 mm²/s], but this difference was not statistically significant (P>0.05). The FA value in the MAU group was higher than that in the control group (0.45±0.07 vs. 0.39±0.03, P = 0.004) but did not differ from that in the NAU group (0.42±0.03) (P>0.05). ADC and FA values may be more sensitive than urine AER in reflecting early-stage kidney injury and, hence, may facilitate earlier detection and quantitative evaluation of kidney injury in T2DM patients. Combined evaluation of ADC and FA values may provide a better quantitative approach for identifying diabetic nephropathy at early disease stages.

关键词： type 2 diabetes mellitus microalbuminuria diffusion weighted imaging diffusion tensor imaging early-stage kidney injury

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移动目标防御：现状及特征 Review

Gui-lin CAI,Bao-sheng WANG,Wei HU,Tian-zuo WANG

《信息与电子工程前沿（英文）》 2016年第17卷第11期页码 1122-1153 doi: 10.1631/FITEE.1601321

摘要：易攻难守是当前网络安全研究面临的核心问题，而移动目标防御（Moving target defense, MTD）为解决这一问题提供了一种全新思路。当前已有涉及MTD多个方面的大量研究被提出。

关键词：移动目标防御；安全模型；功能和移动模型；特征

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An evaluation model of water-saving reconstruction projects based on resource value flows

Runwen JIANG, Xiaohong CHEN, Lingchu ZHAO, Zhifang ZHOU, Tao ZHANG

《工程管理前沿（英文）》 2022年第9卷第2期页码 257-267 doi: 10.1007/s42524-020-0144-y

摘要： Due to uncertainties in water supply, there is growing demand for water resource management in enterprises. In this study, we evaluated the effects of companies’ water-saving reconstruction projects. We used Hina Advanced Materials Company as a case to construct an investment decision model to (1) calculate the internal and external costs of water resources based on circular economic value analysis theory, and (2) locate the level of water resources circulation. We adopted gray situation decision analysis to identify the typical problems that occur in water resource utilization. Moreover, we demonstrated optimization plans for different potential improvements, thereby providing guidance and references for water resource cost management and the comprehensive optimization of environmental benefits. We concluded that the circulation economic value analysis model can effectively display the flow and amount of value derived from water resource flows, thereby providing guidance and suggestions for optimizing water resource flows.

关键词： value flow analysis ternary materials enterprises grey situation decision analysis water resources

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Analysis of synergy degree and its influencing factors in hydropower EPC project management

Jiwei ZHU, Hua GAO, Jiangrui WANG

《工程管理前沿（英文）》 2021年第8卷第3期页码 402-411 doi: 10.1007/s42524-020-0098-0

摘要： The use of engineering procurement construction (EPC) mode is currently a trend in hydropower engineering construction. The clarification of the internal relationship between hydropower EPC projects and the realization of synergy has great significance in improving management efficiency and implementation effect. In this work, a three-dimensional system and a system model of hydropower EPC project management synergy are constructed. The mechanism and factors that influence the degree of management synergy are analyzed on the basis of management synergy theory. Furthermore, the evaluation index system and the degree of synergy model are established, and grey relational analysis is utilized to identify the key factors that affect the synergy degree. Thus, this study aims to facilitate the hydropower EPC project management synergy, provide a quantitative method for synergy degree evaluation, and propose corresponding promotion strategies. Results show that the order degree of each subsystem presents a steady upward trend. Specifically, the order degree of the subsystem at the trial operation stage is low, which is the major restriction on the further improvement of the synergy degree of EPC project management. The key factors in improving the synergy level of hydropower EPC project management are mainly concentrated in the information and organization synergy subsystems, including the construction degree of information platform, the performance of functions, the timeliness of information transfer, and the functions of the information platform.

关键词： hydropower project EPC mode synergy degree model grey relational analysis

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Multi-objective optimization of cutting parameters in high-speed milling based on grey relational analysis

Tao FU, Jibin ZHAO, Weijun LIU

《机械工程前沿（英文）》 2012年第7卷第4期页码 445-452 doi: 10.1007/s11465-012-0338-z

摘要：

This paper investigates optimization problem of the cutting parameters in high-speed milling on NAK80 mold steel. An experiment based on the technology of Taguchi is performed. The objective is to establish a correlation among spindle speed, feed per tooth and depth of cut to the three directions of cutting force in the milling process. In this study, the optimum cutting parameters are obtained by the grey relational analysis. Moreover, the principal component analysis is applied to evaluate the weights so that their relative significance can be described properly and objectively. The results of experiments show that grey relational analysis coupled with principal component analysis can effectively acquire the optimal combination of cutting parameters and the proposed approach can be a useful tool to reduce the cutting force.

关键词： high-speed milling grey relational analysis principal component analysis parameters optimization