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Arithmetic Operations of Generalized Trapezoidal Picture Fuzzy Numbers by Vertex Method
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作者 Mohammad Kamrul Hasan Abeda Sultana Nirmal Kanti Mitra 《American Journal of Computational Mathematics》 2023年第1期99-121,共23页
In this article, we define the arithmetic operations of generalized trapezoidal picture fuzzy numbers by vertex method which is assembled on a combination of the (α, γ, β)-cut concept and standard interval analysis... In this article, we define the arithmetic operations of generalized trapezoidal picture fuzzy numbers by vertex method which is assembled on a combination of the (α, γ, β)-cut concept and standard interval analysis. Various related properties are explored. Finally, some computations of picture fuzzy functions over generalized picture fuzzy variables are illustrated by using our proposed technique. 展开更多
关键词 Picture Fuzzy Set Generalized trapezoidal Picture Fuzzy number γ β)-Cut Arithmetic Operations Vertex Method
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Aggregation operators on intuitionistic trapezoidal fuzzy number and its application to multi-criteria decision making problems 被引量:64
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作者 Wang Jianqiang Zhang Zhong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第2期321-326,共6页
Intuitionistic trapezoidal fuzzy numbers and their operational laws are defined. Based on these operational laws, some aggregation operators, including intuitionistic trapezoidal fuzzy weighted arithmetic averaging op... Intuitionistic trapezoidal fuzzy numbers and their operational laws are defined. Based on these operational laws, some aggregation operators, including intuitionistic trapezoidal fuzzy weighted arithmetic averaging operator and weighted geometric averaging operator are proposed. Expected values, score function, and accuracy function of intuitionitsic trapezoidal fuzzy numbers are defined. Based on these, a kind of intuitionistic trapezoidal fuzzy multi-criteria decision making method is proposed. By using these aggregation operators, criteria values are aggregated and integrated intuitionistic trapezoidal fuzzy numbers of alternatives are attained. By comparing score function and accuracy function values of integrated fuzzy numbers, a ranking of the whole alternative set can be attained. An example is given to show the feasibility and availability of the method. 展开更多
关键词 intuitionistic trapezoidal fuzzy numbers aggregation operators multi-criteria decision making
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Analysis of Friction and Heat Transfer Characteristics of Tubes with Trapezoidal Cut Twisted Tape Inserts
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作者 Shrikant Arunrao Thote Netra Pal Singh 《Fluid Dynamics & Materials Processing》 EI 2023年第3期711-722,共12页
The thermo-hydraulic properties of circular tubes with a twisted tape inside(used accordingly to induce turbulence and enhance heat transfer through the tube wall)are described for Reynolds Numbers ranging from 830 to... The thermo-hydraulic properties of circular tubes with a twisted tape inside(used accordingly to induce turbulence and enhance heat transfer through the tube wall)are described for Reynolds Numbers ranging from 830 to 1990.Tapes twisted with the three distinct twist ratios are considered,namely,6,4.4 and 3.Air is used as the working fluid in several tests.For the sake of comparison,the standard tube with no insert is also examined.It is shown that in the presence of the twisted tape,the‘frictional factor’,‘Nusselt Number’and the‘thermal performance factor’are much higher than those obtained for the plain tube.Moreover,the tapes having the lowest twist ratio,i.e.,3,are more effective than the others in terms of heat transfer augmentation.The‘thermal performance factor’is greater than one for all the twisted tapes used in the experiments,which confirms the enhanced performances of the heat exchanger and the related savings in terms of total energy. 展开更多
关键词 Friction factor nusselt number performance ratio trapezoidal cut twisted tape insert
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Regression Analysis of a Kind of Trapezoidal Fuzzy Numbers Based on a Shape Preserving Operator
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作者 Jie Sun Qiujun Lu 《Journal of Data Analysis and Information Processing》 2017年第3期96-114,共19页
Fuzzy regression provides more approaches for us to deal with imprecise or vague problems. Traditional fuzzy regression is established on triangular fuzzy numbers, which can be represented by trapezoidal numbers. The ... Fuzzy regression provides more approaches for us to deal with imprecise or vague problems. Traditional fuzzy regression is established on triangular fuzzy numbers, which can be represented by trapezoidal numbers. The independent variables, coefficients of independent variables and dependent variable in the regression model are fuzzy numbers in different times and TW, the shape preserving operator, is the only T-norm which induces a shape preserving multiplication of LL-type of fuzzy numbers. So, in this paper, we propose a new fuzzy regression model based on LL-type of trapezoidal fuzzy numbers and TW. Firstly, we introduce the basic fuzzy set theories, the basic arithmetic propositions of the shape preserving operator and a new distance measure between trapezoidal numbers. Secondly, we investigate the specific model algorithms for FIFCFO model (fuzzy input-fuzzy coefficient-fuzzy output model) and introduce three advantages of fit criteria, Error Index, Similarity Measure and Distance Criterion. Thirdly, we use a design set and two reference sets to make a comparison between our proposed model and the reference models and determine their goodness with the above three criteria. Finally, we draw the conclusion that our proposed model is reasonable and has better prediction accuracy, but short of robust, comparing to the reference models by the three goodness of fit criteria. So, we can expand our traditional fuzzy regression model to our proposed new model. 展开更多
关键词 FUZZY Sets LL-Type of trapezoidal FUZZY numberS LEAST-SQUARES DEVIATIONS Shape Preserving OPERATOR FUZZY Linear Regression
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Trapezoidal Approximation of a Fuzzy Number Preserving the Expected Interval and Including the Core
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作者 B. Asady 《American Journal of Operations Research》 2013年第2期299-306,共8页
In this paper, we introduce a method to obtain the nearest trapezoidal approximation of fuzzy numbers so that preserving conditions expect interval and include the core of a fuzzy number.
关键词 trapezoidal APPROXIMATION FUZZY number FUZZY PARTITION FUZZY APPROXIMATION trapezoidal FUZZY numberS
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Obtaining Crisp Priorities for Triangular and Trapezoidal Fuzzy Judgments
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作者 Raman Kumar Goyal Jaskirat Singh +3 位作者 Nidhi Kalra Anshu Parashar Gagan Singla Sakshi Kaushal 《Computer Systems Science & Engineering》 SCIE EI 2022年第4期157-170,共14页
This paper proposes anoptimal fuzzy-based model for obtaining crisp priorities for Fuzzy-AHP comparison matrices.Crisp judgments cannot be given for real-life situations,as most of these include some level of fuzzines... This paper proposes anoptimal fuzzy-based model for obtaining crisp priorities for Fuzzy-AHP comparison matrices.Crisp judgments cannot be given for real-life situations,as most of these include some level of fuzziness and com-plexity.In these situations,judgments are represented by the set of fuzzy numbers.Most of the fuzzy optimization models derive crisp priorities for judgments repre-sented with Triangular Fuzzy Numbers(TFNs)only.They do not work for other types of Triangular Shaped Fuzzy Numbers(TSFNs)and Trapezoidal Fuzzy Numbers(TrFNs).To overcome this problem,a sum of squared error(SSE)based optimization model is proposed.Unlike some other methods,the proposed model derives crisp weights from all of the above-mentioned fuzzy judgments.A fuzzy number is simulated using the Monte Carlo method.A threshold-based constraint is also applied to minimize the deviation from the initial judgments.Genetic Algorithm(GA)is used to solve the optimization model.We have also conducted casestudiesto show the proposed approach’s advantages over the existingmethods.Results show that the proposed model outperforms other models to minimize SSE and deviation from initial judgments.Thus,the proposed model can be applied in various real time scenarios as it can reduce the SSE value upto 29%compared to the existing studies. 展开更多
关键词 Analytic hierarchy process comparison matrices priority vectors fuzzy judgments triangular fuzzy numbers triangular-shaped fuzzy numbers trapezoidal fuzzy numbers
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Numerical Study of Mixed Convection in an Isosceles Trapezoidal Cavity with Several Outlets: Application for Primary Air Draft in ASUTO Charcoal Stove
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作者 Gagnon Koffi Apedanou Kokou N’wuitcha +1 位作者 Yendoubé Lare Kossi Napo 《Modern Mechanical Engineering》 2022年第2期45-61,共17页
Mixed convection of heat and mass transfer in an isosceles trapezoidal cavity has been studied numerically. Constant heat flux is imposed through four outlets and the grid is insulated. The inclined walls are maintain... Mixed convection of heat and mass transfer in an isosceles trapezoidal cavity has been studied numerically. Constant heat flux is imposed through four outlets and the grid is insulated. The inclined walls are maintained in natural convection while the lower horizontal wall is adiabatic. These conditions reflect the air draft zone of the ASUTO charcoal stove. The governing two-di- mensional flow equations have been solved by using the finite difference method and Thomas’s algorithm. The investigations are conducted for different values of Richardson (R<sub>i</sub>), Reynolds number (R<sub>e</sub>) and inclination angles of sidewalls. The results are presented in terms of streamlines, isotherms, moisture contours. It was found that for Reynolds number (R<sub>e</sub>) equal to 100, the flow pattern is strongly dependent on the inclination angle and Richardson number. Thus, for high Richardson number (R<sub>i</sub>) values (10, 100), the dominance of natural convection over the flow structure decreases with the decreasing of the inclination angle of sidewalls of the cavity. For R<sub>i</sub> = 1, an optimum air draft corresponds to an inclination angle in the vicinity of 22° while for R<sub>i</sub> = 10 or 100 (in dominance of natural convection), the optimum inclination angle for air draft is in the vicinity of 15°. 展开更多
关键词 Mixed Convection Heat and Mass Transfer trapezoidal Cavity ASUTO Charcoal Stove Richardson number Several Outlets
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基于FUZZY-BN-FTA的厂区架空燃气管道泄漏可能性研究 被引量:1
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作者 杨斯涵 许开立 《中国安全生产科学技术》 CAS CSCD 北大核心 2024年第2期82-89,共8页
为研究厂区架空燃气管道泄漏的故的可能性,提出模糊数学方法、贝叶斯网络模型以及故障树模型相结合的集成模型。通过GeNIe软件建立架空燃气管道泄漏事故的模糊贝叶斯网络模型;引入Leaky Noisy-or Gate扩展模型对模糊贝叶斯网络中节点的... 为研究厂区架空燃气管道泄漏的故的可能性,提出模糊数学方法、贝叶斯网络模型以及故障树模型相结合的集成模型。通过GeNIe软件建立架空燃气管道泄漏事故的模糊贝叶斯网络模型;引入Leaky Noisy-or Gate扩展模型对模糊贝叶斯网络中节点的条件概率表进行修正,结合基本事件先验概率预测架空燃气管道泄漏的概率值,并引入3个基本事件重要度确定基本事件的重要性排序,同时进行敏感性分析确定主要影响因素,提出控制措施。研究结果表明:厂区车辆撞击、管道疲劳损耗、管材质量不佳、安装设计不合理、焊接缺陷为导致架空燃气管道泄漏的主要因素。研究结果可为工业企业安全管理人员有针对性地制定控制措施,减少事故发生率提供参考。 展开更多
关键词 架空燃气管道泄漏 可能性分析 贝叶斯网络 梯形模糊数 Leaky Noisy-or Gate扩展模型
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关于梯形模糊数排序的新方法 被引量:1
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作者 刘万里 刘艺 《郑州航空工业管理学院学报》 2024年第4期106-112,共7页
关于模糊数排序的问题一直是模糊决策研究的热点。随着研究的深入,研究对象由区间模糊数发展到三角模糊数,进而又发展到梯形模糊数。文章提出一种新的梯形模糊数排序方法,该方法是基于两个梯形模糊数减法法则,通过定积分的运算给出可能... 关于模糊数排序的问题一直是模糊决策研究的热点。随着研究的深入,研究对象由区间模糊数发展到三角模糊数,进而又发展到梯形模糊数。文章提出一种新的梯形模糊数排序方法,该方法是基于两个梯形模糊数减法法则,通过定积分的运算给出可能度的概念,再利用可能度大小和布尔矩阵法对多个模糊数进行排序。最后通过算例显示该方法的可行性,并通过与近期文献的方法比较,显示其有效性和优效性。研究结果表明,该方法不仅能够比较不同类型的模糊数次序,而且计算简单、区分度强,所以应用范围广泛。 展开更多
关键词 梯形模糊数 可能度 布尔矩阵 排序
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基于梯形模糊数的动态混合多属性群决策方法
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作者 林鹏 董春茹 刘萍萍 《河北大学学报(自然科学版)》 CAS 北大核心 2024年第4期337-345,共9页
基于梯形模糊数信息环境,研究动态混合多属性群决策问题.给出梯形模糊数的转化方法及梯形模糊数信息的加权综合集结方法,定义动态梯形模糊加权几何算子;提出不同类别权重的确定方法,利用决策专家的赋值离差和最小化方法确定决策者的权重... 基于梯形模糊数信息环境,研究动态混合多属性群决策问题.给出梯形模糊数的转化方法及梯形模糊数信息的加权综合集结方法,定义动态梯形模糊加权几何算子;提出不同类别权重的确定方法,利用决策专家的赋值离差和最小化方法确定决策者的权重,运用离差最大化模型确定属性权重,基于熵权法和Orness测度赋权法计算时间权重;在此基础上,利用VIKOR(多准则妥协解排序)法提出一种基于梯形模糊数的动态混合多属性群决策方法,并通过算例验证其可行性与有效性. 展开更多
关键词 梯形模糊数 动态混合多属性群决策 加权几何算子 VIKOR法
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基于GAIFWFCM和TFNs的协同过滤算法
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作者 金玉 徐新卫 +2 位作者 陶飞 韩业 陈荣凯 《南阳理工学院学报》 2024年第4期49-57,共9页
针对传统推荐系统中使用离散评分未能合理表达用户偏好的问题,将遗传算法引入优化特征加权模糊C均值,通过梯形模糊聚合相似目标用户,提出基于遗传算法的优化加权模糊C均值聚类融合梯形模糊数的协同过滤模型。通过遗传算法进行增强初始... 针对传统推荐系统中使用离散评分未能合理表达用户偏好的问题,将遗传算法引入优化特征加权模糊C均值,通过梯形模糊聚合相似目标用户,提出基于遗传算法的优化加权模糊C均值聚类融合梯形模糊数的协同过滤模型。通过遗传算法进行增强初始聚类中心,利用优化加权模糊C均值聚类融合梯形模糊数,分析类内与类间属性特征关系,实现用户精细划分,合理过滤推荐。在两组数据集中以MAE和RMSE作为评估指标进行实验,实验结果表明,所提算法在与其余6种算法对比中分类误差更低,对用户意愿识别更加清晰。 展开更多
关键词 协同过滤 梯形模糊数 模糊C均值 遗传算法 特征加权
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基于模糊多属性群决策理论的课堂教学质量评价研究
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作者 胡礼梅 胡月英 《物流科技》 2024年第3期164-167,共4页
考虑学生给定评价信息时的犹豫特性、学生主体之间的差异性以及信息共享的关联性,采用直觉梯形模糊数转换学生群体给定的评价信息,引入模糊测度和Shapley函数值处理存在关联性学生群体的客观权重,并由此构建基于模糊多属性群决策理论的... 考虑学生给定评价信息时的犹豫特性、学生主体之间的差异性以及信息共享的关联性,采用直觉梯形模糊数转换学生群体给定的评价信息,引入模糊测度和Shapley函数值处理存在关联性学生群体的客观权重,并由此构建基于模糊多属性群决策理论的教师课堂教学评价模型,以便于科学、合理地对高校教师课堂教学进行综合评价。 展开更多
关键词 课堂教学评价 多属性群决策 直觉梯形模糊数 Shapley函数值
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A Choquet integral-based TODIM method for q-rung trapezoidal fuzzy numbers and its application in group decision-making
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作者 Benting Wan Juelin Huang 《International Journal of Intelligent Computing and Cybernetics》 EI 2023年第3期545-573,共29页
Purpose–The purpose of this paper is to develop a multi-attribute group decision-making(MAGDM)method under the q-rung orthopair trapezoidal fuzzy environment,which calculates the interaction between the criteria depe... Purpose–The purpose of this paper is to develop a multi-attribute group decision-making(MAGDM)method under the q-rung orthopair trapezoidal fuzzy environment,which calculates the interaction between the criteria depending on the proposed q-rung orthopair trapezoidal fuzzy aggregation Choquet integral(q-ROTrFACI)and employ TODIM(an acronym in Portuguese of Interactive and Multi-criteria Decision Making)to consider the risk psychology of decision-makers,to determine the optimal ranking of alternatives.Design/methodology/approach–In MAGDM,q-rung orthopair trapezoidal fuzzy numbers(q-ROTrFNs)are efficient to indicate the quantitative vagueness of decision-makers.The q-ROTrFACI operator is defined and some properties are proved.Then,a novel similarity measure is developed by fusing the area and coordinates of the q-rung orthopair trapezoidal fuzzy function.Based on the above,a Choquet integral-based TODIM(CI-TODIM)method to consider the risk psychology of decision-makers is proposed and two cases are provided to prove superiority of the method.Findings–The paper investigates q-ROTrFACI operator to productively solve problems with interdependent criteria.Then,an approach is proposed to determine the center point of q–ROTrFNs and a q-rung orthopair trapezoidal fuzzy similarity is constructed.Furthermore,CI-TODIM method is devised based on the proposed q-ROTrFACI operator and similarity in q-rung orthopair trapezoidal fuzzy context.The illustration example of business models’solutions and hypertension health management are given to demonstrate the effectiveness and superiority of proposed method.Originality/value–Thepaperdevelops a novelCI-TODIMmethodthat effectivelysolves the MAGDM problems under the premise of fully considering the priority of criteria and the risk preference of decision-makers,which provides guiding advantages for practical decision-making and enriches the application of decision-making theory. 展开更多
关键词 Multi-criteria group decision-making TODIM Choquet integral Q-rung orthopair trapezoidal fuzzy numbers
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基于模糊故障树的电驱动桥可靠性分析
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作者 傅强 《汽车实用技术》 2024年第17期109-114,共6页
为解决故障树分析时无法获取足够基本事件故障率的问题,文章研究提出模糊故障树分析法。通过将专家判断转化为具体的模糊概率值,从而确定基本事件的发生概率,并完成对故障树顶事件发生概率和关键重要度计算。以某重型卡车的电驱动桥为例... 为解决故障树分析时无法获取足够基本事件故障率的问题,文章研究提出模糊故障树分析法。通过将专家判断转化为具体的模糊概率值,从而确定基本事件的发生概率,并完成对故障树顶事件发生概率和关键重要度计算。以某重型卡车的电驱动桥为例,通过建立电驱动桥不工作的故障树,对模糊故障树进行定量分析,确定了影响系统可靠性的关键故障因素,为相关工作者提供一定的参考借鉴价值。 展开更多
关键词 模糊故障树 梯形模糊数 可靠性分析 重卡电驱动桥
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Ranking Method for Complementary Judgment Matrixes with Fuzzy Numbers Based on Hausdorff Metric Distance 被引量:1
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作者 侯福均 吴祈宗 《Journal of Beijing Institute of Technology》 EI CAS 2005年第4期458-461,共4页
A method for ranking complementary judgment matrixes with traspezoidal fuzzy numbers based on Hausdorff metric distance and fuzzy compromise decision approach is proposed. With regard to fuzzy number complementary jud... A method for ranking complementary judgment matrixes with traspezoidal fuzzy numbers based on Hausdorff metric distance and fuzzy compromise decision approach is proposed. With regard to fuzzy number complementary judgment matrixes given by a decider group whose members have various weights, the expert's information was aggregated first by means of simple weight average(SWA) method and Bonissone calculational method. Hence a matrix including all the experts' preference information was got. Then the matrix' column members were added up and the fuzzy evaluation values of the alternatives were got. Lastly, the Hausdorff metric distance and fuzzy compromise decision approach were used to rank the fuzzy evaluation values and then the ranking values of all the alternatives were got. Because exact numbers and triangular fuzzy numbers could all be transformed into trapezoidal fuzzy numbers, the method developed can rank complementary judgment matrixes with trapezoidal fuzzy numbers, triangular fuzzy numbers and exact numbers as well. An illustrative example is also given to verify the developed method and to demonstrate its feasibility and practicality. 展开更多
关键词 complementary judgment matrix trapezoidal fuzzy number Bonissone calculational method fuzzy compromise decision approach Hausdorff metric distance
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Optimal Solution of Fuzzy Transportation Problem Using Octagonal Fuzzy Numbers
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作者 D.Gurukumaresan C.Duraisamy R.Srinivasan 《Computer Systems Science & Engineering》 SCIE EI 2021年第6期415-421,共7页
In this paper a fuzzy transportation problem under a fuzzy environment is solved using octagonal fuzzy numbers.The transportation problem is significant and has been widely studied in the field of applied mathematics ... In this paper a fuzzy transportation problem under a fuzzy environment is solved using octagonal fuzzy numbers.The transportation problem is significant and has been widely studied in the field of applied mathematics to solve a system of linear equations in many applications in science.Systems of concurrent linear equations play a vital major role in operational research.The main perspective of this research paper is to find out the minimum amount of transportation cost of some supplies through a capacitated network formerly the availability and the demand notes are octagonal fuzzy numbers.Octagonal fuzzy numbers are used and showed a membership function.To illustrate this method,a fuzzy transportation problem is solved by using octagonal fuzzy numbers using the ranking technique.It is shown that it is the best optimal solution and it is demonstrated with a numerical example. 展开更多
关键词 Linear equation transportation problem fuzzy transportation problem ranking technique trapezoidal fuzzy numbers
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复杂网络下密室逃脱类场所火灾风险评估研究 被引量:4
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作者 吕淑然 任泓瑗 +1 位作者 侯捷 程龙 《安全与环境学报》 CAS CSCD 北大核心 2023年第8期2571-2579,共9页
为了预防密室逃脱类场所火灾事故,利用梯形模糊数方法与复杂网络理论,研究密室逃脱类场所火灾事故风险演化过程。通过确定密室逃脱类场所火灾事故风险因素,分析典型火灾事故场景,从宏观角度分析场所内风险因素从被激发、互相影响,最终... 为了预防密室逃脱类场所火灾事故,利用梯形模糊数方法与复杂网络理论,研究密室逃脱类场所火灾事故风险演化过程。通过确定密室逃脱类场所火灾事故风险因素,分析典型火灾事故场景,从宏观角度分析场所内风险因素从被激发、互相影响,最终传递形成人员未能顺利疏散的火灾事故全过程,构建基于复杂网络理论的密室逃脱类场所火灾事故模型。运用梯形模糊数计算各连接边演化过程中的不确定性,采用Dijkstra算法得到最短路径即风险概率最大路径。结果表明:密室逃脱类场内使用明火的初始风险因素作用下,因人员精神状态高度紧张、内部结构复杂或房屋闭锁所导致的火灾演化风险概率最大,并极易造成人员无法疏散。最后从政府等监管部门、场所经营者及参与游戏人员3个方面提出了火灾预防策略。 展开更多
关键词 安全工程 密室逃脱类场所 风险因素 事件树分析 梯形模糊数分析 复杂网络
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融合FCM和TFNs的协同过滤推荐算法 被引量:1
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作者 徐新卫 陶飞 +1 位作者 邓佳佳 周俊 《计算机技术与发展》 2023年第3期161-166,172,共7页
针对推荐算法中的稀疏性问题和传统推荐系统中使用离散评分,用户对物品的喜好程度只能通过5个等级来选取,用户对物品的偏好程度是模糊的且5等级评分不能合理表达用户的喜好,提出一种结合模糊C均值(Fuzzy C-Means, FCM)和梯形模糊数(Trap... 针对推荐算法中的稀疏性问题和传统推荐系统中使用离散评分,用户对物品的喜好程度只能通过5个等级来选取,用户对物品的偏好程度是模糊的且5等级评分不能合理表达用户的喜好,提出一种结合模糊C均值(Fuzzy C-Means, FCM)和梯形模糊数(Trapezoidal Fuzzy Numbers, TFNs)的协同过滤算法。首先,在传统的模糊C均值算法上融合遗传算法,将遗传算法的搜索结果作为模糊C均值的初始聚类中心,以其克服传统FCM搜索极易陷入局部最小值点的缺陷;然后,引入梯形模糊相似度模型,将离散评分数转化为梯形模糊数以此来计算用户相似度,从而利用模糊分数预测估计进行推荐;最后,选取MAE和RMSE作为评估指标,在Movielens数据集中进行实验,实验结果显示所提算法在与其余四种算法对比中预测误差更低,精确度更高,有效提高了推荐质量,也证明了该算法对于稀疏性问题有一定程度上的缓解,表明了该算法的有效性。 展开更多
关键词 协同过滤 梯形模糊数 模糊C均值 遗传算法 离散评分
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倾斜煤层直角梯形巷道支护参数优化的数值模拟研究 被引量:1
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作者 李昊 李娅琪 郑鑫健 《煤炭与化工》 CAS 2023年第4期5-9,13,共6页
倾斜煤层由于其特殊的地层特性,所开采巷道的围岩应力呈现出非对称特征,使得倾斜煤层巷道支护难度高于水平煤层。为了解决严重影响巷道稳定的不平衡应力以及原有支护过剩等问题,以山西黄岩汇5301工作面为实例,通过数值模拟软件FLAC3D分... 倾斜煤层由于其特殊的地层特性,所开采巷道的围岩应力呈现出非对称特征,使得倾斜煤层巷道支护难度高于水平煤层。为了解决严重影响巷道稳定的不平衡应力以及原有支护过剩等问题,以山西黄岩汇5301工作面为实例,通过数值模拟软件FLAC3D分析不同锚索排布、角度、顶锚杆数量条件下的直角梯形巷道的围岩应力,确定最优支护参数。结果表明,当锚索呈“3-3-3”排布且垂直于巷道顶板,顶锚杆数量为6时,数值模拟效果最优,同时根据现场矿压观测结果,优化后的支护参数可以有效保障直角梯形巷道的稳定性。 展开更多
关键词 倾斜煤层 直角梯形巷道 数值模拟 锚索排布 锚索角度 顶锚杆数量
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不确定性条件下分布式农业生产预警模型构建与应用 被引量:1
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作者 王友芝 李强坤 +2 位作者 韩金旭 张翔宇 殷会娟 《农业机械学报》 EI CAS CSCD 北大核心 2023年第5期316-323,共8页
构建了基于梯形模糊数和分布式作物模拟模型的空间分布式农业生产预警模型来实现作物产量和水分生产力综合警情预警预报。模型采用空间分布式作物产量和水分生产力作为警情指标来计算系统警级,引入梯形模糊数来表征目标产量和水分生产... 构建了基于梯形模糊数和分布式作物模拟模型的空间分布式农业生产预警模型来实现作物产量和水分生产力综合警情预警预报。模型采用空间分布式作物产量和水分生产力作为警情指标来计算系统警级,引入梯形模糊数来表征目标产量和水分生产力的不确定性,采用空间分布式作物模拟模型来模拟常规灌溉、0.8倍常规灌溉和0.6倍常规灌溉下的作物产量和水分生产力,进而对现状1976—2012年和未来RCP4.5情景下2026—2045年不同灌溉水平下进行农业生产风险预报预警,并衡量了未来20年产量和水分生产力的静态协调度和每5年4个周期的动态协调度。结果表明,同一作物在不同土壤类型和不同灌溉水平下预警等级不同,警级随着灌溉水平的降低呈现不规则变化规律,协调性随着灌溉水平的降低而减小。模型能够识别出未来气候变化不同节水灌溉水平下的空间异质性作物产量和水分生产力的警级,实现精准化农业生产风险预警预报,有利于实现高效率降警处理。 展开更多
关键词 空间分布式预警 梯形模糊数 亏缺灌溉 RCP4.5情景 气候变化 分布式作物模拟模型
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