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51.
《International Journal of Hydrogen Energy》2022,47(19):10665-10688
The aim of this study is to disclose an integrated multi-criteria decision making model as an instrument able to be used for hydrogen gas grid development via natural gas network conversion by considering four main criteria and sixteen sub-criteria. The proposed model consists of two stages using interval rough based Dombi MARCOS (Measurement Alternatives and Ranking according to the COmpromise Solution) method. In the first stage, the interval rough Bonferroni logarithmic methodology of additive weights is applied for determining the weight coefficients. In the second stage, the improved interval rough MARCOS method is used to rank the alternatives. A case study for hydrogen gas grid development in Romania set out the applicability and effectiveness of the proposed model. The proposed model is analysed from various points of view so that it can be used effectively in reality not only theoretically. This study analyzes four technical alternatives for hydrogen gas grid development. The results show that the conversion for mixtures natural gas with hydrogen a transporting a mix of gases is the best alternative among the four alternatives, for the next period and in the specific context described by this study. The current technical-economic criteria are rather a constraint when discussing gas infrastructures. For choosing a sustainable solution, a major role comes for decision makers, along with the desire to pay fairly from the consumer. 相似文献
52.
为探索出一种工艺简便、成本低且活菌数高的直投式纳豆菌(Bacillus natto)发酵剂的制备方法,该研究以大米粉为基质替代传统的种子液培养基培养纳豆菌后直接将其烘干制成直投式纳豆菌发酵剂,通过单因素及正交试验优化直投式纳豆菌发酵剂的制备工艺。结果表明,用含1.5%蛋白胨的大米粉作为培养基,在接种量4.0%、加水量40%、培养温度43 ℃条件下培养纳豆菌28 h,菌体生长良好,将培养物烘干后制成的直投式纳豆菌发酵剂中的活菌数含量达4.71×109 CFU/g。此技术操作简便,可推广至工业生产中,简化生产过程。 相似文献
53.
54.
针对煤矿安全影响因素多、各影响因素之间相互关联、样本信息采集困难等问题,分析了煤矿安全生产系统风险,从人员、设备、环境、管理四个方面构建了煤矿安全影响因素指标体系,基于粗糙集理论融合最小二乘支持向量机方法的提出了煤矿安全机预警模型,并以实测数据为例对该预警模型的计算结果进行了训练和检验。结果表明,粗糙集融合最小二乘支持向量机能够有效提高预警效率,反映各控制因素对煤矿安全的影响,计算结果与样本值拟合精度较高,对保障煤矿安全生产具有重要而现实的意义。 相似文献
55.
在利用接收信号强度指示(RSSI)对无线传感器网络中的未知节点进行定位时,RSSI 值易受环境的影响导致定位误差,
为此提出基于 RSSI 测距修正的四边形加权质心定位算法(QWCRC)。 先对来自同一锚节点的多个 RSSI 值进行卡尔曼滤波,得
到修正的 RSSI 值,致使测距尽可能的接近真实距离;再采用四边形加权定位对未知节点进行定位,同时利用最小二乘法进行辅
助定位,此算法对于相邻锚节点圆不相交的情况给出新的解决方案。 实验结果对比表明,改进的算法相比较于四边形加权质心
算法(QWC)和 RSSI 测距修正的三角形加权算法(TWCRC),在锚节点数目 5×5 和噪声强度为 0 dbm 时,定位精度可分别提升
87. 14%和 35. 51%。 相似文献
56.
The ordered weighted averaging (OWA) operators play a crucial role in aggregating multiple criteria evaluations into an overall assessment supporting the decision makers’ choice. One key point steps is to determine the associated weights. In this paper, we first briefly review some main methods for determining the weights by using distribution functions. Then we propose a new approach for determining OWA weights by using the regular increasing monotone quantifier. Motivated by the idea of normal distribution-based method to determine the OWA weights, we develop a method based on elliptical distributions for determining the OWA weights, and some of its desirable properties have been investigated. 相似文献
57.
q-Rung orthopair fuzzy sets (q-ROFSs), originally presented by Yager, are a powerful fuzzy information representation model, which generalize the classical intuitionistic fuzzy sets and Pythagorean fuzzy sets and provide more freedom and choice for decision makers (DMs) by allowing the sum of the power of the membership and the power of the nonmembership to be less than or equal to 1. In this paper, a new class of fuzzy sets called q-rung orthopair uncertain linguistic sets (q-ROULSs) based on the q-ROFSs and uncertain linguistic variables (ULVs) is proposed, and this can describe the qualitative assessment of DMs and provide them more freedom in reflecting their belief about allowable membership grades. On the basis of the proposed operational rules and comparison method of q-ROULSs, several q-rung orthopair uncertain linguistic aggregation operators are developed, including the q-rung orthopair uncertain linguistic weighted arithmetic average operator, the q-rung orthopair uncertain linguistic ordered weighted average operator, the q-rung orthopair uncertain linguistic hybrid weighted average operator, the q-rung orthopair uncertain linguistic weighted geometric average operator, the q-rung orthopair uncertain linguistic ordered weighted geometric operator, and the q-rung orthopair uncertain linguistic hybrid weighted geometric operator. Then, some desirable properties and special cases of these new operators are also investigated and studied, in particular, some existing intuitionistic fuzzy aggregation operators and Pythagorean fuzzy aggregation operators are proved to be special cases of these new operators. Furthermore, based on these proposed operators, we develop an approach to solve the multiple attribute group decision making problems, in which the evaluation information is expressed as q-rung orthopair ULVs. Finally, we provide several examples to illustrate the specific decision-making steps and explain the validity and feasibility of two methods by comparing with other methods. 相似文献
58.
Wen Sheng Du 《国际智能系统杂志》2019,34(11):2835-2862
Weighted power means with weights and exponents serving as their parameters are generalizations of arithmetic means. Taking into account decision makers' flexibility in decision making, each attribute value is usually expressed by a -rung orthopair fuzzy value ( -ROFV, ), where the former indicates the support for membership, the latter support against membership, and the sum of their th powers is bounded by one. In this paper, we propose the weighted power means of -rung orthopair fuzzy values to enrich and flourish aggregations on -ROFVs. First, the -rung orthopair fuzzy weighted power mean operator is presented, and its boundedness is precisely characterized in terms of the power exponent. Then, the -rung orthopair fuzzy ordered weighted power mean operator is introduced, and some of its fundamental properties are investigated in detail. Finally, a novel multiattribute decision making method is explored based on developed operators under the -rung orthopair fuzzy environment. A numerical example is given to illustrate the feasibility and validity of the proposed approach, and it is shown that the power exponent is an index suggesting the degree of the optimism of decision makers. 相似文献
59.
水文水资源学家陈守煜先生学术研究的知识图谱分析 总被引:3,自引:0,他引:3
为探索水文水资源学家陈守煜先生学术研究历程及其演变规律,以其335篇文献作为数据基础,采用共现分析等文献计量可视化分析方法,通过文献发表的时间分布、学科和期刊分布、高被引文献分布和研究主题等方面的知识图谱分析,系统分析了陈先生的学术研究历程。结果显示:陈守煜先生学术研究生命周期历时达62年,在其60岁后出现了2个学术创新高峰期;其学术研究特色荟萃于其河渠非恒定流计算、模糊集理论的水文水资源应用、模糊水文水资源学基本理论、模糊聚类-识别-优选统一理论、可变模糊集理论和可变模糊集理论的水文水资源应用6个研究主题,其中主题1为后续的5个模糊水文水资源学创新主题奠定了数值计算的研究方法论,主题2为模糊集现有理论的应用探索,主题3至主题5为面向工程应用的模糊集理论不断深入创新,主题6为可变模糊集理论的应用探索,形成了"紧密结合应用-持续理论创新-创新理论再应用"这种理论与实践互馈的研究特色。他每一阶段的研究目标比较集中、明确,与其研究主题密切对应,显著提高了研究效率;他的学术研究影响广泛,合计被引8554次,缘于他的源头理论创新。陈先生的研究,理论与应用不断互馈,贵在厚积薄发、深入钻研、持续创新,其研究理念和方法论,对水利科学的学术创新研究具有重要的启示作用和深远影响。 相似文献
60.
为准确评价尾矿库的安全等级,以黄金洞尾矿库为例,分析影响尾矿库安全的各因素之间的关系,综合运用模糊多元联系度理论与层次分析法(AHP),建立了包含5个影响因素和26个影响因子的尾矿库综合安全评价模型。由AHP得出各项主、客观指标的权重系数,引入模糊多元联系度理论,综合考虑确定性与不确定性因素,处理综合集成问题,构造隶属函数量化指标的实测值。结果表明:黄金洞尾矿库安全等级为Ⅱ级,尾矿库处于较稳定状态。经比较不确定性因素大小,得出尾矿排放(B3)>尾矿坝(B2)>安全管理(B1)>尾矿输送与回水(B5)>排洪系统(B4),说明尾矿排放指标的不确定性因素最大,需对尾矿排放加强管理。该模型得到的评价结果与实际结果相吻合,为尾矿库安全性评价提供了一种可行的方法。 相似文献