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Suitable sets for strongly topological gyrogroups
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作者 LIN Fu-cai BAO Meng SHI Ting-ting 《Applied Mathematics(A Journal of Chinese Universities)》 2026年第1期30-45,共16页
A discrete subset S of a topological gyrogroup G with the identity 0 is said to be a suitable set for G if it generates a dense subgyrogroup of G and S∪{0}is closed in G.In this paper,it is proved that each countable... A discrete subset S of a topological gyrogroup G with the identity 0 is said to be a suitable set for G if it generates a dense subgyrogroup of G and S∪{0}is closed in G.In this paper,it is proved that each countable Hausdorff topological gyrogroup has a suitable set;moreover,it is shown that each separable metrizable strongly topological gyrogroup has a suitable set. 展开更多
关键词 suitable sets gyrogroups (strongly)topological gyrogroups left precompact PSEUDOCOMPACT separable space metrizable space
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Fuzzy Attention Convolutional Neural Networks:A Novel Approach Combining Intuitionistic Fuzzy Sets and Deep Learning
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作者 Zheng Zhao Doo Heon Song Kwang Baek Kim 《Computers, Materials & Continua》 2026年第5期752-783,共32页
Deep learning attentionmechanisms have achieved remarkable progress in computer vision,but still face limitations when handling images with ambiguous boundaries and uncertain feature representations.Conventional atten... Deep learning attentionmechanisms have achieved remarkable progress in computer vision,but still face limitations when handling images with ambiguous boundaries and uncertain feature representations.Conventional attention modules such as SE-Net,CBAM,ECA-Net,and CA adopt a deterministic paradigm,assigning fixed scalar weights to features without modeling ambiguity or confidence.To overcome these limitations,this paper proposes the Fuzzy Attention Network Layer(FANL),which integrates intuitionistic fuzzy set theory with convolutional neural networks to explicitly represent feature uncertainty through membership(μ),non-membership(ν),and hesitation(π)degrees.FANLconsists of four coremodules:(1)feature dimensionality reduction via global pooling,(2)fuzzymodeling using learnable clustering centers,(3)adaptive attention generation through weighted fusion of fuzzy components,and(4)feature refinement through residual connections.A cross-layer guidance mechanism is further introduced to enhance hierarchical feature propagation,allowing high-level semantic features to incorporate fine-grained texture information from shallow layers.Comprehensive experiments on three benchmark datasets—PathMNIST-30000,full PathMNIST,and Blood MNIST—demonstrate the effectiveness and generalizability of FANL.The model achieves 84.41±0.56%accuracy and a 1.69%improvement over the baseline CNN while maintaining lightweight computational complexity.Ablation studies show that removing any component causes a 1.7%–2.0%performance drop,validating the synergistic contribution of each module.Furthermore,FANL provides superior uncertainty calibration(ECE=0.0452)and interpretable selective prediction under uncertainty.Overall,FANL presents an efficient and uncertaintyaware attention framework that improves both accuracy and reliability,offering a promising direction for robust visual recognition under ambiguous or noisy conditions. 展开更多
关键词 Attention mechanism deep learning intuitionistic fuzzy set PathMNIST
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A Synergistic Multi-Attribute Decision-Making Method for Educational Institutions Evaluation Using Similarity Measures of Possibility Pythagorean Fuzzy Hypersoft Sets
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作者 Khuram Ali Khan Saba Mubeen Ishfaq +1 位作者 Atiqe Ur Rahman Salwa El-Morsy 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期501-530,共30页
Due to the numerous variables to take into account as well as the inherent ambiguity and uncertainty,evaluating educational institutions can be difficult.The concept of a possibility Pythagorean fuzzy hypersoft set(pP... Due to the numerous variables to take into account as well as the inherent ambiguity and uncertainty,evaluating educational institutions can be difficult.The concept of a possibility Pythagorean fuzzy hypersoft set(pPyFHSS)is more flexible in this regard than other theoretical fuzzy set-like models,even though some attempts have been made in the literature to address such uncertainties.This study investigates the elementary notions of pPyFHSS including its set-theoretic operations union,intersection,complement,OR-and AND-operations.Some results related to these operations are also modified for pPyFHSS.Additionally,the similarity measures between pPyFHSSs are formulated with the assistance of numerical examples and results.Lastly,an intelligent decision-assisted mechanism is developed with the proposal of a robust algorithm based on similarity measures for solving multi-attribute decision-making(MADM)problems.A case study that helps the decision-makers assess the best educational institution is discussed to validate the suggested system.The algorithmic results are compared with the most pertinent model to evaluate the adaptability of pPyFHSS,as it generalizes the classical possibility fuzzy set-like theoretical models.Similarly,while considering significant evaluating factors,the flexibility of pPyFHSS is observed through structural comparison. 展开更多
关键词 Hypersoft set Pythagorean fuzzy hypersoft set computational complexity multi-attribute decision-making optimization similarity measures uncertainty
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Transformer-based identification for ADS-B transmitters in open–time sets 被引量:1
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作者 Yunfei ZHENG Xuejun ZHANG +1 位作者 Yuanhao TAN Xueyuan LI 《Chinese Journal of Aeronautics》 2025年第8期470-484,共15页
Radio Frequency Fingerprint Identification(RFFI)technology provides a means of identifying spurious signals.This technology has been widely used in solving Automatic Dependent Surveillance–Broadcast(ADS-B)signal spoo... Radio Frequency Fingerprint Identification(RFFI)technology provides a means of identifying spurious signals.This technology has been widely used in solving Automatic Dependent Surveillance–Broadcast(ADS-B)signal spoofing problems.However,the effects of circuit changes over time often lead to a decline in identification accuracy within open-time set.This paper proposes an ADS-B transmitter identification method to solve the degradation of identification accuracy.First,a real-time data processing system is established to receive and store ADS-B signals to meet the conditions for open-time set.The system possesses the following functionalities:data collection,data parsing,feature extraction,and identity recognition.Subsequently,a two-dimensional TimeFrequency Feature Diagram(TFFD)is proposed as a signal pre-processing method.The TFFD is constructed from the received ADS-B signal and the reconstructed signal for input to the recognition model.Finally,incorporating a frequency offset layer into the Swin Transformer architecture,a novel recognition network framework is proposed.This integration can enhance the network recognition accuracy and robustness by tailoring to the specific characteristics of ADSB signals.Experimental results indicate that the proposed recognition architecture achieves recognition accuracy of 95.86%in closed-time set and 84.33%in open-time set,surpassing other algorithms. 展开更多
关键词 Automatic Dependent Surveillance-Broadcast Radio frequency fingerprinting IDENTIFICATION Open-time set Time-frequency feature diagram Swin Transformer
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On Bowen Entropy for Stable Sets in Positive Entropy Systems
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作者 ZHANG Zhengwei YAN Kesong ZENG Fanping 《数学进展》 北大核心 2025年第1期99-112,共14页
In this paper,we study the Bowen entropy of stable sets in positive entropy G-system of amenable group actions.The lower bound of the Bowen entropy of these sets are estimated.
关键词 positive entropy stable set Bowen entropy amenable group action
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Fuzzy N-Bipolar Soft Sets for Multi-Criteria Decision-Making:Theory and Application
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作者 Sagvan Y.Musa Baravan A.Asaad +2 位作者 Hanan Alohali Zanyar A.Ameen Mesfer H.Alqahtani 《Computer Modeling in Engineering & Sciences》 2025年第4期911-943,共33页
This paper introduces fuzzy N-bipolar soft(FN-BS)sets,a novel mathematical framework designed to enhance multi-criteria decision-making(MCDM)processes under uncertainty.The study addresses a significant limitation in ... This paper introduces fuzzy N-bipolar soft(FN-BS)sets,a novel mathematical framework designed to enhance multi-criteria decision-making(MCDM)processes under uncertainty.The study addresses a significant limitation in existing models by unifying fuzzy logic,the consideration of bipolarity,and the ability to evaluate attributes on a multinary scale.The specific contributions of the FN-BS framework include:(1)a formal definition and settheoretic foundation,(2)the development of two innovative algorithms for solving decision-making(DM)problems,and(3)a comparative analysis demonstrating its superiority over established models.The proposed framework is applied to a real-world case study on selecting vaccination programs across multiple countries,showcasing consistent DM outcomes and exceptional adaptability to complex and uncertain scenarios.These results position FN-BS sets as a versatile and powerful tool for addressing dynamic DM challenges. 展开更多
关键词 Fuzzy N-bipolar soft sets N-bipolar soft sets N-soft sets MCDM ALGORITHMS
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Urban Transportation Strategy Selection for Multi-Criteria Group Decision-Making Using Pythagorean Fuzzy N-Bipolar Soft Expert Sets
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作者 Sagvan Y.Musa Zanyar A.Ameen +1 位作者 Wafa Alagal Baravan A.Asaad 《Computer Modeling in Engineering & Sciences》 2025年第9期3493-3529,共37页
Urban transportation planning involves evaluating multiple conflicting criteria such as accessibility,cost-effectiveness,and environmental impact,often under uncertainty and incomplete information.These complex decisi... Urban transportation planning involves evaluating multiple conflicting criteria such as accessibility,cost-effectiveness,and environmental impact,often under uncertainty and incomplete information.These complex decisions require input from various stakeholders,including planners,policymakers,engineers,and community representatives,whose opinions may differ or contradict.Traditional decision-making approaches struggle to effectively handle such bipolar and multivalued expert evaluations.To address these challenges,we propose a novel decisionmaking framework based on Pythagorean fuzzy N-bipolar soft expert sets.This model allows experts to express both positive and negative opinions on a multinary scale,capturing nuanced judgments with higher accuracy.It introduces algebraic operations and a structured aggregation algorithm to systematically integrate and resolve conflicting expert inputs.Applied to a real-world case study,the framework evaluated five urban transport strategies based on key criteria,producing final scores as follows:improving public transit(−0.70),optimizing traffic signal timing(1.86),enhancing pedestrian infrastructure(3.10),expanding bike lanes(0.59),and implementing congestion pricing(0.77).The results clearly identify enhancing pedestrian infrastructure as the most suitable option,having obtained the highest final score of 3.10.Comparative analysis demonstrates the framework’s superior capability in modeling expert consensus,managing uncertainty,and supporting transparent multi-criteria group decision-making. 展开更多
关键词 Pythagorean fuzzy N-bipolar soft expert sets N-soft sets pythagorean fuzzy sets MCGDM urban transportation
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Schweizer-Sklar T-Norm Operators for Picture Fuzzy Hypersoft Sets: Advancing Suistainable Technology in Social Healthy Environments
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作者 Xingsi Xue Himanshu Dhumras +2 位作者 Garima Thakur Rakesh Kumar Bajaj Varun Shukla 《Computers, Materials & Continua》 2025年第7期583-606,共24页
Ensuring a sustainable and eco-friendly environment is essential for promoting a healthy and balanced social life.However,decision-making in such contexts often involves handling vague,imprecise,and uncertain informat... Ensuring a sustainable and eco-friendly environment is essential for promoting a healthy and balanced social life.However,decision-making in such contexts often involves handling vague,imprecise,and uncertain information.To address this challenge,this study presents a novel multi-criteria decision-making(MCDM)approach based on picture fuzzy hypersoft sets(PFHSS),integrating the flexibility of Schweizer-Sklar triangular norm-based aggregation operators.The proposed aggregation mechanisms—weighted average and weighted geometric operators—are formulated using newly defined operational laws under the PFHSS framework and are proven to satisfy essential mathematical properties,such as idempotency,monotonicity,and boundedness.The decision-making model system-atically incorporates both benefit and cost-type criteria,enabling more nuanced evaluations in complex social or environmental decision problems.To enhance interpretability and practical relevance,the study conducts a sensitivity analysis on the Schweizer-Sklar parameter(Δ).The results show that varyingΔaffects the strictness of aggregation,thereby influencing the ranking stability of alternatives.A comparative analysis with existing fuzzy and hypersoft-based MCDM methods confirms the robustness,expressiveness,and adaptability of the proposed approach.Notably,the use of picture fuzzy sets allows for the inclusion of positive,neutral,and negative memberships,offering a richer representation of expert opinions compared to traditional models.A case study focused on green technology adoption for environmental sustainability illustrates the real-world applicability of the proposed method.The analysis confirms that the approach yields consistent and interpretable results,even under varying degrees of decision uncertainty.Overall,this work contributes an efficient and flexible MCDM tool that can support decision-makers in formulating policies aligned with sustainable and socially responsible outcomes. 展开更多
关键词 Hypersoft set picture fuzzy set Schweizer-Sklar norms aggregation operators DECISION-MAKING green technology adoption
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Development of AHP-Based Divergence Distance Measure between P,q,r-Spherical Fuzzy Sets with Applications in Multi-Criteria Decision Making
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作者 Shah Zeb Khan Muhammad Rahim +3 位作者 Adel M.Widyan A.Almutairi Njood Shaher Ethaar Almutire Hamiden Abd El-Wahed Khalifa 《Computer Modeling in Engineering & Sciences》 2025年第5期2185-2211,共27页
This study introduces a novel distance measure(DM)for(p,q,r)-spherical fuzzy sets((p,q,to improve decision-making in complex and uncertain environments.Many existing distance measures eitherr)-SFSs)fail to satisfy ess... This study introduces a novel distance measure(DM)for(p,q,r)-spherical fuzzy sets((p,q,to improve decision-making in complex and uncertain environments.Many existing distance measures eitherr)-SFSs)fail to satisfy essential axiomatic properties or produce unintuitive outcomes.To address these limitations,we propose a new three-dimensional divergence-based DM that ensures mathematical consistency,enhances the discrimination of information,and adheres to the axiomatic framework of distance theory.Building on this foundation,we construct a multi-criteria decision-making(MCDM)model that utilizes the proposed DM to evaluate and rank alternatives effectively.The applicability and robustness of the model are validated through a practical case study,demonstrating that it leads to more rational,consistent,and reliable decision outcomes compared to existing approaches. 展开更多
关键词 p q r-spherical fuzzy sets DIVERGENCE distance measures AHP decision making
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以美丽中国建设为素材的化学SETS试题赏析
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作者 林淑秧 《中学化学教学参考》 2025年第24期89-91,共3页
建设“美丽中国”已经纳入我国“十三五”规划,高考中有关“美丽中国”建设命制的SETS试题,涉及(Science)、环境(Environment)、技术(Technology)、社会(Society)等化学教育中的需要概念在高考中高频出现,从美丽乡村建设、推进绿色转型... 建设“美丽中国”已经纳入我国“十三五”规划,高考中有关“美丽中国”建设命制的SETS试题,涉及(Science)、环境(Environment)、技术(Technology)、社会(Society)等化学教育中的需要概念在高考中高频出现,从美丽乡村建设、推进绿色转型、创造美好生活、发展科技强国等方面进行热点解读,赏析相关试题并进行高考预测。 展开更多
关键词 sets试题 绿色转型 科技强国
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THE CONVEX SETS OF CONSTANT WIDTH CONSTRUCTED FROM OPPOSITE SECTORS
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作者 Fengfan XIE Yong YANG 《Acta Mathematica Scientia》 2025年第1期118-125,共8页
This paper presents a method for constructing a convex set of constant width from opposite sectors.
关键词 convex set constant width opposite sectors
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Comparison of three 16S rRNA gene primer sets for the study of planktonic archaeal communities in the Antarctic Peninsula region
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作者 Zuoqi Wang Yinxin Zeng +5 位作者 Miming Zhang Yu Du Wei Han Ting Hu Yongqiang Hu Haitao Ding 《Acta Oceanologica Sinica》 2025年第11期201-214,共14页
Despite being ubiquitous in oceans and important in marine biogeochemical cycles,planktonic archaea in the Southern Ocean(SO)remain poorly characterized.Although high-throughput sequencing(HTS)approaches based on 16S ... Despite being ubiquitous in oceans and important in marine biogeochemical cycles,planktonic archaea in the Southern Ocean(SO)remain poorly characterized.Although high-throughput sequencing(HTS)approaches based on 16S ribosomal RNA(rRNA)genes have been used widely to study the diversity and composition of microbial community in natural environments,primer-set selection is critical because of amplicon-sequencing bias during metabarcoding.Here,using surface-seawater samples collected from the area between the South Shetland and South Orkney Islands,Antarctica,we compared primer sets Arch349F/Arch806R,515F-Y/926R,and 524F/Arch958R,which target different 16S rRNA gene hypervariable regions to identify the best one for studying planktonic archaeal communities.With much lower number of bacteria-related sequences,primer set 524F/Arch958R showed higher values of archaeal operational taxonomic units(OTUs)as well as alpha-diversity indices,indicating that this primer set was more specific for detecting archaeal species and could be helpful to obtain more comprehensive information on the archaeal community compositions compared to other two primer sets.Compared with primer set Arch349F/Arch806R revealing four phyla(Halobacteriota,Methanobacteriota,Thermoplasmatota,and Thermoproteota)detected in seawater,additional archaeal phyla were observed by 515F-Y/926R(Asgardarchaeota and Nanoarchaeota)and 524F/Arch958R(Micrarchaeota).In spite of the differences in archaeal community compositions observed among the three investigated primer sets,ammonia-oxidizing(e.g.,Nitrososphaeria)and methane-producing(e.g.,Methanobacteria,Methanomicrobia,and Methanosarcinia)archaea were the main groups detected in the surface seawater,indicating the ecological role of planktonic archaea in carbon and nitrogen cycling in the upper waters of the SO.These results underscore the importance of primer-set selection when studying archaeal community diversity and composition in the Antarctic SO. 展开更多
关键词 primer set 16S rRNA gene planktonic archaeal community Southern Ocean ANTARCTIC
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Construction methods of nonlocal sets of orthogonal product states on multipartite quantum systems
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作者 Guang-Bao Xu Zhao-Xia Zhong +1 位作者 Yu-Guang Yang Dong-Huan Jiang 《Chinese Physics B》 2025年第11期309-316,共8页
Nonlocal set of orthogonal product states(OPSs)can improve the confidentiality of information when it is used to design quantum cryptographic protocols.It is a difficult question how to construct a nonlocal set of OPS... Nonlocal set of orthogonal product states(OPSs)can improve the confidentiality of information when it is used to design quantum cryptographic protocols.It is a difficult question how to construct a nonlocal set of OPSs on general multipartite and high dimensional quantum systems.Different from the previous works,we first present a novel method for constructing a nonlocal product set with 3d-2 members on C^(d)■C^(d)■C^(d)quantum system for d≥3.Then,we extend this construction method to C^(d_(1))■C^(d_(2))■C^(d_(3))quantum system and■_(i=1)^(n)C^(di)quantum system respectively,where 3≤d_(1)≤d_(2)≤d_(3)≤…≤dC_(d_(i))and n≥3.The nonlocal set of OPSs constructed by our method contains fewer elements than those constructed by the existing methods,except for one special case.More importantly,the set of states constructed by our method has a completely different structure from those constructed by the existing methods since our nonlocal set does not contain a“stopper”state.Our result is helpful to further understand the different structures of nonlocal sets on multipartite systems. 展开更多
关键词 nonlocal set local indistinguishability orthogonality-preserving measurement quantum nonlocality without entanglement
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Methodology for the Ensemble Synthesis of Stochastic Seismic Event Sets Satisfying the Renewal Process for Local Strong Earthquakes
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作者 Cheng Jiang Pan Hua 《Applied Geophysics》 2025年第4期988-1002,1492,1493,共17页
Local strong seismic activity shows the potential to closely follow a renewal process,which is inconsistent with the overall seismic activity that aligns with the Poisson process.Given that existing methods for synthe... Local strong seismic activity shows the potential to closely follow a renewal process,which is inconsistent with the overall seismic activity that aligns with the Poisson process.Given that existing methods for synthesizing stochastic seismic event sets cannot control local seismic activity,a method based on Monte Carlo simulations has been developed for synthesizing random seismic event sets where local strong earthquakes satisfy the renewal process.This method can synthesize seismic activities in a statistical area where the overall activity conforms to the Poisson process and the major seismic activities in local potential sources or faults follow the renewal process.This paper presents long-and short-scale approaches.The long-scale earthquake catalogs are suitable for reflecting the sequential characteristics of seismic activities.Meanwhile,the short-scale catalogs focus on the impacts of specific earthquake events within a group for a detailed understanding of hazards under certain conditions,making them suitable for studies on specific earthquake sequences and geological areas or situations requiring high temporal resolution.In the applications of shortscale sequences,we find that the equivalent occurrence rate method may overestimate the seismic hazard.This synthesis method for earthquake catalogs can simulate realistic seismic activities,thereby enhancing the accuracy of hazard analysis results and is suitable for seismic hazard analysis and earthquake insurance rate setting. 展开更多
关键词 Seismic Random Event Set Monte Carlo Poisson Process Renewal Process
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Layer-2 transferable belief model:Manage uncertainty on random permutation sets
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作者 Qian-Li Zhou Yong Deng 《Journal of Electronic Science and Technology》 2025年第2期52-64,共13页
In this paper,the transferable belief model established on power sets is extended to the permutation event space(PES)and is referred to as the layer-2 transferable belief model.Our goal is to provide a comprehensive a... In this paper,the transferable belief model established on power sets is extended to the permutation event space(PES)and is referred to as the layer-2 transferable belief model.Our goal is to provide a comprehensive approach for handling and modeling uncertainty,capable of representing both quantitative and qualitative information.First,the motivation for proposing the layer-2 transferable belief model and its information processing principles are explored from the perspective of weak propensity.Then,based on these principles,the corresponding information processing methods for the credal and pignistic levels are developed.Finally,the advantages of this model are validated through a classifier that leverages attribute fusion to enhance performance and decision-making accuracy. 展开更多
关键词 Evidence theory Information processing Information fusion Layer-2 belief structure Random permutation set
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Cardinal Numbers of Fuzzy Sets 被引量:8
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作者 李洪兴 罗承忠 +1 位作者 汪培庄 袁学海 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第3期101-107,共7页
Up to now, the study on the cardinal number of fuzzy sets has advanced at on pace since it is very hard to give it an appropriate definition. Althrough for it in [1], it is with some harsh terms and is not reasonable ... Up to now, the study on the cardinal number of fuzzy sets has advanced at on pace since it is very hard to give it an appropriate definition. Althrough for it in [1], it is with some harsh terms and is not reasonable as we point out in this paper. In the paper, we give a general definition of fuzzy cardinal numbers. Based on this definition, we not only obtain a large part of results with re spect to cardinal numbers, but also give a few of new properties of fuzzy cardinal numbers. 展开更多
关键词 Fuzzy relations Fuzzy mappings the cardinal numbers of fuzzy sets
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NEW METHOD FOR MEASURING FUZZINESS IN ROUGH SETS 被引量:4
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作者 何亚群 胡寿松 魏崇辉 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第1期31-35,共5页
A method with the fuzzy entropy for measuring fuzziness to fuzzy problem in rough sets is proposed. A new sort of the fuzzy entropy is given. The calculating formula and the equivalent expression method with the fuzzy... A method with the fuzzy entropy for measuring fuzziness to fuzzy problem in rough sets is proposed. A new sort of the fuzzy entropy is given. The calculating formula and the equivalent expression method with the fuzzy entropy in rough sets based on equivalence relation are provided, and the properties of the fuzzy entropy are proved. The fuzzy entropy based on equivalent relation is extended to generalize the fuzzy entropy based on general binary relation, and the calculating formula and the equivalent expression of the generalized fuzzy entropy are also given. Finally, an example illustrates the way for getting the fuzzy entropy. Results show that the fuzzy entropy can conveniently measure the fuzziness in rough sets. 展开更多
关键词 rough sets FUZZINESS fuzzy entropy generalized fuzzy entropy
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激光烧蚀TC4熔池行为数值模拟
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作者 姜永霞 李隆 +2 位作者 余天锡 程雨露 张春玲 《应用光学》 北大核心 2026年第2期411-419,共9页
激光加工金属材料的过程涉及复杂的物理现象,其内在机理涵盖多个学科和领域。本研究基于Level Set方法,在有限元仿真软件中构建了激光加工TC4钛合金形成熔池的数值模型,系统深入地探究了温度场、速度场及金属相变的动态行为。该模型采用... 激光加工金属材料的过程涉及复杂的物理现象,其内在机理涵盖多个学科和领域。本研究基于Level Set方法,在有限元仿真软件中构建了激光加工TC4钛合金形成熔池的数值模型,系统深入地探究了温度场、速度场及金属相变的动态行为。该模型采用Level Set方法精确追踪气/液相变界面,并利用热焓-孔隙法处理液/固混合糊状区,从而在有限元仿真软件中实现了高精度的数值模拟。揭示了激光参数(功率、光斑半径)对熔池温度场、速度场及相变行为的影响规律。研究结果表明:高功率密度和小光斑半径能够显著提高熔池的流速和温度,加速材料的相变过程,但也可能导致液体喷溅和表面粗糙度增加。这些结果为优化激光加工工艺参数、提高加工质量提供了重要的理论依据。 展开更多
关键词 激光加工 TC4 Level Set 相变 数值模拟
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基于Rough Sets的中医指症挖掘研究与应用 被引量:2
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作者 丁卫平 管致锦 顾春华 《计算机工程与应用》 CSCD 北大核心 2008年第7期234-237,共4页
针对中医病历数据库中指症样本维数较大、数据特征和属性冗余量较多等特征,在对Rough Sets基本理论和属性约简算法研究的基础上,提出了将属性频度和属性重要性相结合的GENRED_GROWTH中医指症挖掘算法,并进行了基于GENRED_GROWTH的中医... 针对中医病历数据库中指症样本维数较大、数据特征和属性冗余量较多等特征,在对Rough Sets基本理论和属性约简算法研究的基础上,提出了将属性频度和属性重要性相结合的GENRED_GROWTH中医指症挖掘算法,并进行了基于GENRED_GROWTH的中医指症挖掘原型系统设计与实现。通过分析和实验结果表明:该算法能较好地进行中医指症属性约简,分类精度较高,并且能抽取中医指症相关诊断规则以辅助医生的诊断和治疗。 展开更多
关键词 ROUGH sets 属性约简 中医指症 数据挖掘
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Question classification in question answering based on real-world web data sets 被引量:1
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作者 袁晓洁 于士涛 +1 位作者 师建兴 陈秋双 《Journal of Southeast University(English Edition)》 EI CAS 2008年第3期272-275,共4页
To improve question answering (QA) performance based on real-world web data sets,a new set of question classes and a general answer re-ranking model are defined.With pre-defined dictionary and grammatical analysis,t... To improve question answering (QA) performance based on real-world web data sets,a new set of question classes and a general answer re-ranking model are defined.With pre-defined dictionary and grammatical analysis,the question classifier draws both semantic and grammatical information into information retrieval and machine learning methods in the form of various training features,including the question word,the main verb of the question,the dependency structure,the position of the main auxiliary verb,the main noun of the question,the top hypernym of the main noun,etc.Then the QA query results are re-ranked by question class information.Experiments show that the questions in real-world web data sets can be accurately classified by the classifier,and the QA results after re-ranking can be obviously improved.It is proved that with both semantic and grammatical information,applications such as QA, built upon real-world web data sets, can be improved,thus showing better performance. 展开更多
关键词 question classification question answering real-world web data sets question and answer web forums re-ranking model
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