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Finite Temperature Magnetism in the Triangular Lattice Antiferromagnet KErTe_(2)
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作者 Weiwei Liu Zheng Zhang +6 位作者 Dayu Yan Jianshu Li Zhitao Zhang Jianting Ji Feng Jin Youguo Shi Qingming Zhang 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第9期140-150,共11页
After the discovery of the ARECh2(A=alkali or monovalent ions,RE=rare-earth,Ch=chalcogen)triangular lattice quantum spin liquid(QSL)family,a series of its oxide,sulfide,and selenide counterparts has been consistently ... After the discovery of the ARECh2(A=alkali or monovalent ions,RE=rare-earth,Ch=chalcogen)triangular lattice quantum spin liquid(QSL)family,a series of its oxide,sulfide,and selenide counterparts has been consistently reported and extensively investigated.While KErTe_(2) represents the initial synthesized telluride member,preserving its triangular spin lattice,it was anticipated that the substantial tellurium ions could impart more pronounced magnetic attributes and electronic structures to this material class.This study delves into the magnetism of KErTe_(2) at finite temperatures through magnetization and electron spin resonance(ESR)measurements.Based on the angular momentum J after spin-orbit coupling(SOC)and symmetry analysis,we obtain the magnetic effective Hamiltonian to describe the magnetism of Er^(3+)in R3m space group.Applying the mean-field approximation to the Hamiltonian,we can simulate the magnetization and magnetic heat capacity of KErTe_(2) in paramagnetic state and determine the crystalline electric field(CEF)parameters and partial exchange interactions.The relatively narrow energy gaps between the CEF ground state and excited states exert a significant influence on the magnetism.For example,small CEF excitations can result in a significant broadening of the ESR linewidth at 2 K.For the fitted exchange interactions,although the values are small,given a large angular momentum J=15/2 after SOC,they still have a noticeable effect at finite temperatures.Notably,the heat capacity data under different magnetic fields along the𝑐axis direction also roughly match our calculated results,further validating the reliability of our analytical approach.These derived parameters serve as crucial tools for future investigations into the ground state magnetism of KErTe_(2).The findings presented herein lay a foundation for exploration of the intricate magnetism within the triangular-lattice delafossite family. 展开更多
关键词 triangular HAMILTONIAN MAGNETIZATION
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Does the Hartman effect exist in triangular barriers
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作者 李青玲 郑爽 肖智 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期214-230,共17页
We study the phase,Larmor and dwell times of a particle scattered off triangular barriers(TBs).It is interesting that the dependences of dwell,reflective phase and Larmor times on the wave number,barrier width and hei... We study the phase,Larmor and dwell times of a particle scattered off triangular barriers(TBs).It is interesting that the dependences of dwell,reflective phase and Larmor times on the wave number,barrier width and height for a pair of mirror-symmetric(MS)exact triangular barriers(ETBs)are quite different,as the two ETBs have quite distinct scattering surfaces.In comparison,the dependence of the transmitted phase or Larmor times is exactly the same,since the transmitted amplitudes are the same for a pair of MS TBs.We further study the Hartman effect by defining the phase and Larmor velocities associated with the phase and Larmor times.We find no barrier width saturation effect for the transmitted and reflected times.This is indicated by the fact that all the velocities approach finite constants that are much smaller than the speed of light in vacuum for TBs with positive-slope impact faces.As for ETBs with vertical left edges,the naive velocities seem to also indicate the absence of the Hartman effect.These are quite distinct from rectangular barriers and may shed new light on the clarification of the tunneling time issues. 展开更多
关键词 triangular barrier Hartman effect
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Review and update on the management of triangular fibrocartilage complex injuries in professional athletes
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作者 Valerio Pace Francesco Bronzini +2 位作者 Giovanni Novello Giuseppe Mosillo Luca Braghiroli 《World Journal of Orthopedics》 2024年第2期110-117,共8页
Triangular fibrocartilage complex injuries are common in amateur and professional sports.These injuries are mainly caused by acute or chronic repetitive axial loads on the wrist,particularly on the ulnar side and in a... Triangular fibrocartilage complex injuries are common in amateur and professional sports.These injuries are mainly caused by acute or chronic repetitive axial loads on the wrist,particularly on the ulnar side and in association with rotations or radial/ulnar deviations.In order to treat professional athletes,a detailed specific knowledge of the pathology is needed.Moreover,the clinician should fully understand the specific and unique environment and needs of the athletes,their priorities and goals,the type of sport,the time of the season,and the position played.An early diagnosis and appropriate management with the quickest possible recovery time are the uppermost goals for both the athlete and the surgeon.A compromise between conservative vs surgical indications,athletes’needs and expectations,and financial implications should be achieved.Arthroscopic procedures should be timely planned when indicated as they could allow early diagnosis and treatment at the same time.Conservative measures are often used as first line treatment when possible.Peripheral lesions are treated by arthroscopic repair,whilst central lesions are treated by arthroscopic debridement.Further procedures(such as the Wafer procedure,ulnar osteotomies,etc.)have specific indications and great implications with regard to rehabilitation. 展开更多
关键词 triangular fibrocartilage complex injuries Professional athletes Ulnar sided wrist pain Wrist arthroscopy Wrist debridement
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Constructing a Triangular Linkage Model of Government Audit,Social Audit,and Internal Audit to Promote High-Quality Development of Audit Services
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作者 TANG Pengzhan 《Journal of Modern Accounting and Auditing》 2024年第3期89-98,共10页
It is a complex and important topic to study the linkage mechanism of government audit,social audit,and internal audit in the context of China’s high-quality economic development.The implementation of measures,such a... It is a complex and important topic to study the linkage mechanism of government audit,social audit,and internal audit in the context of China’s high-quality economic development.The implementation of measures,such as establishing a sound and perfect organizational safeguard mechanism,strengthening project collaborative audit mechanism,enhancing the mechanism for utilizing audit results,and establishing an audit and rectification joint mechanism can promote the efficient operation of the audit supervision system and the high-quality development of audit services. 展开更多
关键词 government audit social audit internal audit triangular linkage model high-quality development
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Misdiagnosis of hemangioma of left triangular ligament of the liver as gastric submucosal stromal tumor:Two case reports
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作者 Jing-Jie Wang Fen-Ming Zhang +4 位作者 Wei Chen Hua-Tuo Zhu Ning-Long Gui Ai-Qing Li Hong-Tan Chen 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第7期2351-2357,共7页
BACKGROUND Extragastric lesions are typically not misdiagnosed as gastric submucosal tumor(SMT).However,we encountered two rare cases where extrinsic lesions were misdiagnosed as gastric SMTs.CASE SUMMARY We describe ... BACKGROUND Extragastric lesions are typically not misdiagnosed as gastric submucosal tumor(SMT).However,we encountered two rare cases where extrinsic lesions were misdiagnosed as gastric SMTs.CASE SUMMARY We describe two cases of gastric SMT-like protrusions initially misdiagnosed as gastric SMTs by the abdominal contrast-enhanced computed tomography(CT)and endoscopic ultrasound(EUS).Based on the CT and EUS findings,the patients underwent gastroscopy;however,no tumor was identified after incising the gastric wall.Subsequent surgical exploration revealed no gastric lesions in both patients,but a mass was found in the left triangular ligament of the liver.The patients underwent laparoscopic tumor resection,and the postoperative diagnosis was hepatic hemangiomas.CONCLUSION During EUS procedures,scanning across different layers and at varying degrees of gastric cavity distension,coupled with meticulous image analysis,has the potential to mitigate the likelihood of such misdiagnoses. 展开更多
关键词 Submucosal tumor Extragastric compression Endoscopic ultrasonography Computed tomography Hemangioma of the left triangular ligament of the liver Case report
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Phonon Focusing Effect in an Atomic Level Triangular Structure
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作者 姜剑辉 鲁爽 陈杰 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第9期61-65,共5页
The rise of artificial microstructures has made it possible to modulate propagation of various kinds of waves,such as light,sound and heat.Among them,the focusing effect is a modulation function of particular interest... The rise of artificial microstructures has made it possible to modulate propagation of various kinds of waves,such as light,sound and heat.Among them,the focusing effect is a modulation function of particular interest.We propose an atomic level triangular structure to realize the phonon focusing effect in single-layer graphene.In the positive incident direction,our phonon wave packet simulation results confirm that multiple features related to the phonon focusing effect can be controlled by adjusting the height of the triangular structure.More interestingly,a completed different focusing pattern and an enhanced energy transmission coefficient are found in the reverse incident direction.The detailed mode conversion physics is discussed based on the Fourier transform analysis on the spatial distribution of the phonon wave packet.Our study provides physical insights to achieving phonon focusing effect by designing atomic level microstructures. 展开更多
关键词 STRUCTURE PHONON triangular
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Four-Order Superconvergent Weak Galerkin Methods for the Biharmonic Equation on Triangular Meshes
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作者 Xiu Ye Shangyou Zhang 《Communications on Applied Mathematics and Computation》 EI 2023年第4期1323-1338,共16页
A stabilizer-free weak Galerkin(SFWG)finite element method was introduced and analyzed in Ye and Zhang(SIAM J.Numer.Anal.58:2572–2588,2020)for the biharmonic equation,which has an ultra simple finite element formulat... A stabilizer-free weak Galerkin(SFWG)finite element method was introduced and analyzed in Ye and Zhang(SIAM J.Numer.Anal.58:2572–2588,2020)for the biharmonic equation,which has an ultra simple finite element formulation.This work is a continuation of our investigation of the SFWG method for the biharmonic equation.The new SFWG method is highly accurate with a convergence rate of four orders higher than the optimal order of convergence in both the energy norm and the L^(2)norm on triangular grids.This new method also keeps the formulation that is symmetric,positive definite,and stabilizer-free.Four-order superconvergence error estimates are proved for the corresponding SFWG finite element solutions in a discrete H^(2)norm.Superconvergence of four orders in the L^(2)norm is also derived for k≥3,where k is the degree of the approximation polynomial.The postprocessing is proved to lift a P_(k)SFWG solution to a P_(k+4)solution elementwise which converges at the optimal order.Numerical examples are tested to verify the theor ies. 展开更多
关键词 Finite element Weak Hessian Weak Galerkin(WG) Biharmonic equation triangular mesh
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Anomaly Detection of UAV State Data Based on Single-Class Triangular Global Alignment Kernel Extreme Learning Machine
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作者 Feisha Hu Qi Wang +2 位作者 Haijian Shao Shang Gao Hualong Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第9期2405-2424,共20页
Unmanned Aerial Vehicles(UAVs)are widely used and meet many demands in military and civilian fields.With the continuous enrichment and extensive expansion of application scenarios,the safety of UAVs is constantly bein... Unmanned Aerial Vehicles(UAVs)are widely used and meet many demands in military and civilian fields.With the continuous enrichment and extensive expansion of application scenarios,the safety of UAVs is constantly being challenged.To address this challenge,we propose algorithms to detect anomalous data collected from drones to improve drone safety.We deployed a one-class kernel extreme learning machine(OCKELM)to detect anomalies in drone data.By default,OCKELM uses the radial basis(RBF)kernel function as the kernel function of themodel.To improve the performance ofOCKELM,we choose a TriangularGlobalAlignmentKernel(TGAK)instead of anRBF Kernel and introduce the Fast Independent Component Analysis(FastICA)algorithm to reconstruct UAV data.Based on the above improvements,we create a novel anomaly detection strategy FastICA-TGAK-OCELM.The method is finally validated on the UCI dataset and detected on the Aeronautical Laboratory Failures and Anomalies(ALFA)dataset.The experimental results show that compared with other methods,the accuracy of this method is improved by more than 30%,and point anomalies are effectively detected. 展开更多
关键词 UAV safety kernel extreme learning machine triangular global alignment kernel fast independent component analysis
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Relative Ding Projective Modules over Formal Triangular Matrix Rings
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作者 Hongyan Fan Xi Tang 《Journal of Applied Mathematics and Physics》 2023年第6期1598-1614,共17页
Let U be a (B, A)-bimodule, A and B be rings, and be a formal triangular matrix ring. In this paper, we characterize the structure of relative Ding projective modules over T under some conditions. Furthermore, using t... Let U be a (B, A)-bimodule, A and B be rings, and be a formal triangular matrix ring. In this paper, we characterize the structure of relative Ding projective modules over T under some conditions. Furthermore, using the left global relative Ding projective dimensions of A and B, we estimate the relative Ding projective dimension of a left T-module. 展开更多
关键词 Formal triangular Matrix Ring Relative Ding Projective Module Relative Ding Projective Dimension
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Introduction to Mesh Based Generated Lumped Parameter Models for Electromagnetic Problems using Triangular Elements
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作者 Haidar Y.Diab Salim Asfirane +2 位作者 Nicolas Bracikowski Frédéric Gillon Yacine Amara 《CES Transactions on Electrical Machines and Systems》 CSCD 2023年第1期21-34,共14页
This paper is an introduction to mesh based generated reluctance network modeling using triangular elements.Many contributions on mesh based generated reluctance networks using rectangular shaped elements have been pu... This paper is an introduction to mesh based generated reluctance network modeling using triangular elements.Many contributions on mesh based generated reluctance networks using rectangular shaped elements have been published,but very few on those generated from a mesh using triangular elements.The use of triangular elements is aimed at extending the application of the approach to any shape of modeled devices.Basic concepts of the approach are presented in the case of electromagnetic devices.The procedure for coding the approach in the case of a flat linear permanent magnet machine is presented.Codes developed under MATLAB environment are also included. 展开更多
关键词 Lumped parameter modeling Finite element method MESH triangular elements Electromagnetic devices MODELING
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Pythagorean probabilistic hesitant triangular fuzzy aggregation operators with applications in multiple attribute decision making
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作者 LIAO Fuping LI Wu +1 位作者 LIU Gang ZHOU Xiaoqiang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第2期422-438,共17页
As a generalization of fuzzy set,hesitant probabilistic fuzzy set and pythagorean triangular fuzzy set have their own unique advantages in describing decision information.As modern socioeconomic decision-making proble... As a generalization of fuzzy set,hesitant probabilistic fuzzy set and pythagorean triangular fuzzy set have their own unique advantages in describing decision information.As modern socioeconomic decision-making problems are becoming more and more complex,it also becomes more and more difficult to appropriately depict decision makers’cognitive information in decision-making process.In order to describe the decision information more comprehensively,we define a pythagorean probabilistic hesitant triangular fuzzy set(PPHTFS)by combining the pythagorean triangular fuzzy set and the probabilistic hesitant fuzzy set.Firstly,the basic operation and scoring function of the pythagorean probabilistic hesitant triangular fuzzy element(PPHTFE)are proposed,and the comparison rule of two PPHTFEs is given.Then,some pythagorean probabilistic hesitant triangular fuzzy aggregation operators are developed,and their properties are also studied.Finally,a multi-attribute decision-making(MADM)model is constructed based on the proposed operators under the pythagorean probabilistic hesitant triangular fuzzy information,and an illustration example is given to demonstrate the practicability and validity of the proposed decision-making method. 展开更多
关键词 pythagorean probabilistic hesitant triangular fuzzy set(PPHTFS) aggregation operator multi-attribute decisionmaking(MADM)
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Two-Parameter Block Triangular Splitting Preconditioner for Block Two-by-Two Linear Systems
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作者 Bo Wu Xingbao Gao 《Communications on Applied Mathematics and Computation》 EI 2023年第4期1601-1615,共15页
This paper proposes a two-parameter block triangular splitting(TPTS)preconditioner for the general block two-by-two linear systems.The eigenvalues of the corresponding preconditioned matrix are proved to cluster aroun... This paper proposes a two-parameter block triangular splitting(TPTS)preconditioner for the general block two-by-two linear systems.The eigenvalues of the corresponding preconditioned matrix are proved to cluster around 0 or 1 under mild conditions.The limited numerical results show that the TPTS preconditioner is more efficient than the classic block-diagonal and block-triangular preconditioners when applied to the flexible generalized minimal residual(FGMRES)method. 展开更多
关键词 Block triangular splitting Block two-by-two linear systems Eigenvalues PRECONDITIONER flexible generalized minimal residual(FGMRES)
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关节镜下桡尺远侧韧带重建治疗慢性PalmerⅠD型三角纤维软骨复合体损伤疗效观察
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作者 杨顺 程亚博 +3 位作者 向往 张静 陈柯屹 虞亚明 《中国运动医学杂志》 CAS CSCD 北大核心 2024年第7期512-517,共6页
目的:探讨腕关节镜辅助下异体肌腱重建桡尺远侧韧带治疗慢性PalmerⅠD型三角纤维软骨复合体损伤伴桡尺远侧关节不稳的临床疗效。方法:回顾性分析我院2017年1月至2020年1月收治的15例慢性PalmerⅠD型三角纤维软骨复合体损伤患者临床资料... 目的:探讨腕关节镜辅助下异体肌腱重建桡尺远侧韧带治疗慢性PalmerⅠD型三角纤维软骨复合体损伤伴桡尺远侧关节不稳的临床疗效。方法:回顾性分析我院2017年1月至2020年1月收治的15例慢性PalmerⅠD型三角纤维软骨复合体损伤患者临床资料,均给予腕关节镜辅助下异体肌腱重建桡尺远侧韧带治疗,术后随访并评价腕关节的活动度、腕关节疼痛视觉模拟评分(VAS评分)、握力、腕关节功能评分(改良Mayo评分)。结果:所有患者术后随访12~24个月,平均18.15±2.20个月。术后15例患者腕关节疼痛VAS评分为2.56±0.69分,与术前的6.78±1.24分比较差异有统计学意义(P<0.05),疼痛显著缓解。术后患侧手和健侧手的握力比率为(76.18±9.72)%,与术前的(50.18±6.79)%比较差异具有统计学意义(P<0.05),握力显著增大。术后腕关节旋转活动度为(151.09±12.38)°,较术前的(142.87±10.19)°有显著改善,差异有统计学意义(P<0.05)。按照改良Mayo评分,优8例,良6例,可1例,优良率为93.33%。结论:腕关节镜辅助下异体肌腱重建桡尺远侧韧带治疗慢性PalmerⅠD型三角纤维软骨复合体损伤伴桡尺远侧关节不稳疗效确切,可促进疼痛、握力、旋转活动度的改善。 展开更多
关键词 三角纤维软骨复合体损伤 腕关节镜 韧带重建
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砖木结构古建筑火灾风险影响因子评估研究 被引量:1
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作者 李明海 杨一帆 常通 《工业安全与环保》 2024年第2期49-54,共6页
提出模糊DEMATEL-ISM的方法,在建立古建筑火灾评价指标体系的基础上,对归属于4大类风险因素的25个潜在风险因子进行关联性分析,得出因子的因果属性及因子间的逻辑层次结构关系,从而对古建筑火灾风险进行评估。利用模糊DEMATEL-ISM法对... 提出模糊DEMATEL-ISM的方法,在建立古建筑火灾评价指标体系的基础上,对归属于4大类风险因素的25个潜在风险因子进行关联性分析,得出因子的因果属性及因子间的逻辑层次结构关系,从而对古建筑火灾风险进行评估。利用模糊DEMATEL-ISM法对华阴市西岳庙灏灵殿进行实例分析,结果表明:疏散与扑救条件、电器设备隐患的原因度较大,需要对其予以控制;耐火等级、火灾荷载的结果度大,为事故发生的主要原因;疏散与扑救条件、易燃易爆危险品、电器设备隐患、安全责任制、灭火应急预案和演练为古建筑火灾事故的关键风险因子,可为古建筑火灾风险管控工作提供相应参考。 展开更多
关键词 古建筑 火灾事故 风险分析 三角模糊数 决策与实验室分析法 解释结构模型
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三角形排列波浪锥柱绕流流动特性数值分析
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作者 邹琳 吴伟男 +2 位作者 王家辉 郑云龙 徐汉斌 《东南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第1期224-231,共8页
采用大涡模拟方法,分析了亚临界雷诺数为3 900时三角形排列波浪锥柱的横流向间距比和顺流向间距比对其升阻力特性、尾流干涉效应及三维流动结构等的影响.结果表明,上游2个波浪锥柱的升阻力特性受下游波浪锥柱影响较小,下游波浪锥柱处于... 采用大涡模拟方法,分析了亚临界雷诺数为3 900时三角形排列波浪锥柱的横流向间距比和顺流向间距比对其升阻力特性、尾流干涉效应及三维流动结构等的影响.结果表明,上游2个波浪锥柱的升阻力特性受下游波浪锥柱影响较小,下游波浪锥柱处于上游双波浪锥柱尾流中,其升阻力特性受横流向间距比和顺流向间距比影响更为显著.3个波浪锥柱间的流动状态可分为邻近干扰、漩涡撞击和涡相互作用状态.在漩涡撞击状态下,上游波浪锥柱尾涡得以发展充分,周期性撞击在下游波浪锥柱表面,从而产生较大的脉动升力.横流向间距比、顺流向间距比分别为3和6时,下游波浪锥柱脉动升力系数较单直圆柱提升了20.93倍. 展开更多
关键词 波浪锥柱 三角形排列 大涡模拟 流动结构 振动增强
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三角迷宫式侧堰的水力特性研究
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作者 李珊珊 曹顶业 +1 位作者 沈桂莹 李国栋 《力学季刊》 CAS CSCD 北大核心 2024年第1期177-186,共10页
迷宫式侧堰具有较大的泄流能力,广泛应用于流量控制、农田灌溉和排水系统.为研究三角迷宫式侧堰的复杂水力特性、泄流规律及泄流影响因素,本研究首先基于FLOW-3D软件和RNG k-ε湍流模型,对侧堰的15种工况进行数值模拟计算,获得侧堰水面... 迷宫式侧堰具有较大的泄流能力,广泛应用于流量控制、农田灌溉和排水系统.为研究三角迷宫式侧堰的复杂水力特性、泄流规律及泄流影响因素,本研究首先基于FLOW-3D软件和RNG k-ε湍流模型,对侧堰的15种工况进行数值模拟计算,获得侧堰水面流态、流速分布等水力特性.同时,通过白金汉π定理推出影响迷宫式侧堰流量系数的无量纲参数,探究流量系数C_(d)与无量纲参数之间的变化规律,利用人工智能遗传规划(Genetic Programming,GP)算法拟合出流量系数计算公式.结果表明:主渠道内水流为缓流,堰顶角θ较小时,二次流使得水面流态变化,流速在靠近侧堰时发生急剧变化,堰内产生回流.随着θ的增大,堰顶上方水舌从对称分布变为偏右侧下泄,堰内回流现象消失;C_d随上游弗劳德数Fr和溢流前沿与堰顶水深之比l/h_(1)的增加而减小,随堰高与堰上水头之比p/h_(1)的增加而增加,θ越大,C_(d)变化趋势越大;流量系数预测公式在测试阶段的决定系数R^(2)=0.913,均方根误差RMSE=0.045,流量系数预测值与试验值的散点图拟合效果良好,数据点分布均匀且关于拟合线对称,表明GP模型得出的结果较为准确,满足灌区量水精度要求.该研究成果可为迷宫式侧堰在实际工程中的应用提供理论依据和技术支撑. 展开更多
关键词 三角迷宫式侧堰 水力特性 遗传规划算法 数值模拟
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基于联系数投影的三角模糊数组合预测模型及其应用
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作者 田成诗 袁宏俊 相瑞兵 《运筹与管理》 CSCD 北大核心 2024年第1期115-122,共8页
在模糊预测中,三角模糊数比区间数更能准确刻画不确定信息。针对三角模糊数组合预测,本文首先引入集对分析中联系数,找出三角模糊数与三元联系数的转换关系,巧妙回避三角模糊数组合预测运算的模糊性和复杂性。其次定义三元联系数运算规... 在模糊预测中,三角模糊数比区间数更能准确刻画不确定信息。针对三角模糊数组合预测,本文首先引入集对分析中联系数,找出三角模糊数与三元联系数的转换关系,巧妙回避三角模糊数组合预测运算的模糊性和复杂性。其次定义三元联系数运算规则,构建联系数投影作为最优准则,建立联系数投影的定权系数三角模糊数组合预测模型。然后依据高精度预测方法应赋予较大权系数的原则,构建联系数广义诱导有序加权平均(CNGIOWA)算子,研究其性质定理,再结合联系数投影的最优准则,建立基于联系数投影和CNGIOWA算子的变权系数三角模糊数组合预测模型。最后将两类三角模糊数组合预测模型应用到模糊预测实证分析中,结果显示两类组合预测模型都能有效提高预测准确性。 展开更多
关键词 三角模糊数 三元联系数 组合预测 联系数投影 CNGIOWA算子
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基于改进AHP及云模型的水轮机调节系统状态评价
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作者 张彬桥 杨洋 +1 位作者 刘雷 马昭 《人民长江》 北大核心 2024年第5期219-225,共7页
针对水轮机调节系统综合评价不够全面,无法综合反映系统多指标、多层次的复杂性问题,提出了基于模糊层次分析法(AHP)-决策与实验室评估法(DEMATEL)-云模型的水轮机调节系统综合评价模型。首先建立基于主要设备和相关工况的多层次指标体... 针对水轮机调节系统综合评价不够全面,无法综合反映系统多指标、多层次的复杂性问题,提出了基于模糊层次分析法(AHP)-决策与实验室评估法(DEMATEL)-云模型的水轮机调节系统综合评价模型。首先建立基于主要设备和相关工况的多层次指标体系,采用模糊AHP计算评价指标的初始权重;通过DEMATEL法计算评价指标的相互影响与参照关系,绘制出指标因果关系图,并结合初始权重计算评价指标的综合权重;引入云模型得到评价指标各等级的隶属度矩阵。最后将权重结果与隶属度结合,得到系统综合评价等级。算例分析表明,该方法可高效快捷地对水轮机调节系统运行状态进行客观评价,为状态检修提供参考依据。 展开更多
关键词 水轮机调节系统 综合评价 三角模糊理论 云模型 DEMATEL
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