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Common Fixed Point Theorems for Sequences of φ-type Contraction Set-valued Mappings 被引量:9
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作者 WU Jian-rong LIU Hai-yan 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第4期504-510,共7页
In complete metric spaces, the common fixed point theorems for sequences of φ-type contraction set-valued mappings are established, and the corresponding random com- mon fixed point theorems for set-valued mappings a... In complete metric spaces, the common fixed point theorems for sequences of φ-type contraction set-valued mappings are established, and the corresponding random com- mon fixed point theorems for set-valued mappings are also obtained. 展开更多
关键词 sequence of set-valued mappings common fixed point random fixed point metric space
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Formal Concept Analysis Based on Set-valued Mapping
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作者 CHEN Li-ya HUANG Tao +1 位作者 SONG Zhen-ming PEI Zheng 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期390-396,共7页
Formal concept analysis (FCA) is a discipline that studied the hierarchical structures induced by a binary relation between a pair of sets, and applies in data analysis, information retrieval, knowledge discovery, e... Formal concept analysis (FCA) is a discipline that studied the hierarchical structures induced by a binary relation between a pair of sets, and applies in data analysis, information retrieval, knowledge discovery, etc. In this paper, it is shown that a formal context T is equivalent to a set-valued mapping S : G → P(М), and formal concepts could be defined in the set-valued mapping S. It is known that the topology and set-valued mapping are linked. Hence, the advantage of this paper is that the conclusion make us to construct formal concept lattice based on the topology. 展开更多
关键词 FCA set-valued mapping ISOMORPHISM
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Natural Mappings on Set-valued Mapping Spaces
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作者 LI Zu-quan WANG Jiu-jing 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第1期21-25,共5页
In this paper,we discuss the continuities of some natural mappings on pointcompact continuous set-valued mapping spaces with compact-open topology and obtain the properties of set-valued injective mappings,set-valued ... In this paper,we discuss the continuities of some natural mappings on pointcompact continuous set-valued mapping spaces with compact-open topology and obtain the properties of set-valued injective mappings,set-valued diagonal mappings,induced mappings,set-valued evaluation mappings,set-valued topological sum mappings and set-valued topological product mappings. 展开更多
关键词 set-valued mapping compact-open topology natural mapping
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Common Fixed Point Theorems of Single-valued and Set-valued Mappings in Complete,Convex Metric Spaces 被引量:1
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作者 LIANGJun-qi ZHANGZhi-hong ZHAOLing 《Chinese Quarterly Journal of Mathematics》 CSCD 2003年第3期264-270,共7页
Under the conditions of compatility or sub -c ompatility between a sigle-valued mapping and set-valued mapping, this paper d iscusses the existence of common fixed points for two set-valued mappings and a single-value... Under the conditions of compatility or sub -c ompatility between a sigle-valued mapping and set-valued mapping, this paper d iscusses the existence of common fixed points for two set-valued mappings and a single-valued mapping in complete, convex matric spaces. We extend and develop the main results. 展开更多
关键词 complete convex metric spaces compatible mappings s ub-compatible mappings common fixed point theorems
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A FIXED POINT THEOREM FOR SET-VALUED MAPPINGS
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作者 Amitabh Banerjee 1, Thakur Balwant Singh 2 (1 Department of Mathematics, Govt D B Girls P G College, Raipur (M P), 492001, India 2 Govt B H S S, Gariaband, Dist Raipur (M P), 493889, India) (Communicated by CHIEN Wei_zang) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第12期1397-1403,共7页
Fixed points for set_valued mappings from a metric space X (not necessarily complete) into B(X), the collection of nonempty bounded subsets of X are obtained. The result generalizes some known results.
关键词 fixed point set_valued mappings metric space
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A survey of ergodicity on the set-valued mappings
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作者 ZHANGYu-cheng LIAOGong-fu 《海南师范学院学报(自然科学版)》 2004年第4期305-311,共7页
In this paper, we give a survey on the PhD thesis of the first author. There theexistence and ergodicity on invariant measures of set-valued mappings are discused.
关键词 set-valued mapping INVARIANT measure ERGODIC MARKOV operator Mark-ov transition function lower SEMICONTINUOUS continuous selection
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A REMARK ON THE DERIVATE OF SET-VALUED MAPPING 被引量:1
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作者 Chen Bing(Dept. of Math. Jinzhou Teachers CollegeJinzhou 121003) 《数学研究》 CSCD 1994年第1期51-55,共5页
AREMARKONTHEDERIVATEOFSET-VALUEDMAPPING¥ChenBing(Dept.ofMath.JinzhouTeachersCollegeJinzhou121003)Abstract:Th... AREMARKONTHEDERIVATEOFSET-VALUEDMAPPING¥ChenBing(Dept.ofMath.JinzhouTeachersCollegeJinzhou121003)Abstract:Thederivateofset-va... 展开更多
关键词 集值映射 H-导出数 集值积分 巴拿赫空间
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On Ekeland's Variational Principle for Set-Valued Mappings
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作者 Sheng-jie Li Wen-yan Zhang 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2007年第1期141-148,共8页
In this paper, we derive a general vector Ekeland variational principle for set-valued mappings, which has a dosed relation to εk^0 -efficient points of set-valued optimization problems. The main result presented in ... In this paper, we derive a general vector Ekeland variational principle for set-valued mappings, which has a dosed relation to εk^0 -efficient points of set-valued optimization problems. The main result presented in this paper is a generalization of the corresponding result in [3]. 展开更多
关键词 Vector Ekeland variational principle nonlinear scalarization function metric space set-valued mapping
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Coincidence Theorem for Admissible Set-valued Mappings and Its Applications in FC-spaces
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作者 Ming-ge Yang Lei Deng 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2010年第3期455-462,共8页
A new coincidence theorem for admissible set-valued mappings is proved in FC-spaces with a more general convexity structure. As applications, an abstract variational inequality, a KKM type theorem and a fixed point th... A new coincidence theorem for admissible set-valued mappings is proved in FC-spaces with a more general convexity structure. As applications, an abstract variational inequality, a KKM type theorem and a fixed point theorem are obtained. Our results generalize and improve the corresponding results in the literature. 展开更多
关键词 FC-SPACE coincidence theorem admissible set-valued mapping
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Proximal point algorithm for a new class of fuzzy set-valued variational inclusions with (H,η)-monotone mappings
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作者 李红刚 《Journal of Chongqing University》 CAS 2008年第1期79-84,共6页
We introduced a new class of fuzzy set-valued variational inclusions with (H,η)-monotone mappings. Using the resolvent operator method in Hilbert spaces, we suggested a new proximal point algorithm for finding approx... We introduced a new class of fuzzy set-valued variational inclusions with (H,η)-monotone mappings. Using the resolvent operator method in Hilbert spaces, we suggested a new proximal point algorithm for finding approximate solutions, which strongly converge to the exact solution of a fuzzy set-valued variational inclusion with (H,η)-monotone. The results improved and generalized the general quasi-variational inclusions with fuzzy set-valued mappings proposed by Jin and Tian Jin MM, Perturbed proximal point algorithm for general quasi-variational inclusions with fuzzy set-valued mappings, OR Transactions, 2005, 9(3): 31-38, (In Chinese); Tian YX, Generalized nonlinear implicit quasi-variational inclusions with fuzzy mappings, Computers & Mathematics with Applications, 2001, 42: 101-108. 展开更多
关键词 variational inclusion (H η)-monotone mapping resolvent operator technique fuzzy set-valued mapping proximal point algorithm: convergence of numerical methods
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A Fixed Point Theorem for Set-Valued Mapping in Abstract Convex Space with Application
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作者 范晓冬 向淑文 《Journal of Mathematical Research and Exposition》 CSCD 2009年第4期716-720,共5页
A new fixed point theorem and the selection property for upper semi-continuous set-valued mappings in abstract convexity space are established. As their applications the existence of Nash equilibrium for n-person non-... A new fixed point theorem and the selection property for upper semi-continuous set-valued mappings in abstract convexity space are established. As their applications the existence of Nash equilibrium for n-person non-cooperative generalized games is proved. 展开更多
关键词 set-valued mapping fixed point continuous selection Nash equilibrium.
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Continuous selections for pseudo-lower semicontinuous set-valued mappings on convex structure spaces and hyperspace contractibility
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作者 Li, L Wu, CX 《Chinese Science Bulletin》 SCIE EI CAS 1997年第14期1230-1231,共2页
SINCE 1956, Michael’s continuous selection theory has been applied to functional analysis,topology, approximation theory and other mathematical fields. In this letter, the concept ofthe pseudo-lower semicontinuity is... SINCE 1956, Michael’s continuous selection theory has been applied to functional analysis,topology, approximation theory and other mathematical fields. In this letter, the concept ofthe pseudo-lower semicontinuity is introduced, and a convex structure of metric space is de-fined. A continuous selection theorem for pseudo-lower semicontinuity is given. This 展开更多
关键词 Continuous selections for pseudo-lower semicontinuous set-valued mappings on convex structure spaces and hyperspace contractibility
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Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models
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作者 Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models Duc-Dam Nguyen Nguyen Viet Tiep +5 位作者 Quynh-Anh Thi Bui Hiep Van Le Indra Prakash Romulus Costache Manish Pandey Binh Thai Pham 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期467-500,共34页
This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble lear... This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble learning techniques:DAGGING(DG),MULTIBOOST(MB),and ADABOOST(AB).This combination resulted in three distinct ensemble models:DG-RBFN,MB-RBFN,and AB-RBFN.Additionally,a traditional weighted method,Information Value(IV),and a benchmark machine learning(ML)model,Multilayer Perceptron Neural Network(MLP),were employed for comparison and validation.The models were developed using ten landslide conditioning factors,which included slope,aspect,elevation,curvature,land cover,geomorphology,overburden depth,lithology,distance to rivers and distance to roads.These factors were instrumental in predicting the output variable,which was the probability of landslide occurrence.Statistical analysis of the models’performance indicated that the DG-RBFN model,with an Area Under ROC Curve(AUC)of 0.931,outperformed the other models.The AB-RBFN model achieved an AUC of 0.929,the MB-RBFN model had an AUC of 0.913,and the MLP model recorded an AUC of 0.926.These results suggest that the advanced ensemble ML model DG-RBFN was more accurate than traditional statistical model,single MLP model,and other ensemble models in preparing trustworthy landslide susceptibility maps,thereby enhancing land use planning and decision-making. 展开更多
关键词 Landslide susceptibility map spatial analysis ensemble modelling information values(IV)
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Transitivity, mixing and chaos for a class of set-valued mappings 被引量:9
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作者 LIAO Gongfu, WANG Lidong & ZHANG Yucheng Institute of Mathematics, Jilin University, Changchun 130012, China Institute of Nonlinear Information Technology, Dalian Nations University, Dalian 116600, China Department of Mathematics, University of Science and Technology of China, Hefei 230026, China 《Science China Mathematics》 SCIE 2006年第1期1-8,共8页
Consider the continuous map f : x → X and the continuous map f of K,(X) into itself induced by f, where X is a metric space and K(X) the space of all non-empty compact subsets of x endowed with the Hausdorff metric. ... Consider the continuous map f : x → X and the continuous map f of K,(X) into itself induced by f, where X is a metric space and K(X) the space of all non-empty compact subsets of x endowed with the Hausdorff metric. According to the questions whether the chaoticity of f implies the chaoticity of f posed by Roman-Flores and when the chaoticity of f implies the chaoticity of f posed by Fedeli, we investigate the relations between f and f in the related dynamical properties such as transitivity, weakly mixing and mixing, etc. And by using the obtained results, we give the satisfied answers to Roman-Flores's question and Fedeli's question. 展开更多
关键词 set-valued mapping transitivity WEAK mixing mixing chaos.
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Iterative Processes with Errors for Generalized Set-Valued φ-Hemi-contractive Mapping in Banach Spaces
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作者 张勇 《Journal of Southwest Jiaotong University(English Edition)》 2006年第2期194-199,共6页
A new conception of generalized set-valued Ф-hemi-contractive mapping in Banach spaces is presented. Some strong convergence theorems of Ishikawa and Mann iterative approximation with errors is proved. The results in... A new conception of generalized set-valued Ф-hemi-contractive mapping in Banach spaces is presented. Some strong convergence theorems of Ishikawa and Mann iterative approximation with errors is proved. The results in this paper improve and extend the earlier results. 展开更多
关键词 Generalized set-valued Ф-hemi-contractive mapping Ishikawa and Mann iterative processes with errors q-uniformlysmooth Banach space Hausdorff metric Generalized duality mapping
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THE RELATIONSHIP BETWEEN THE CONE-WEAK SUBDIFFERENTIAL AND CONE-WEAK DIRECTION DERIVATIVE FOR CONVEX SET-VALUED MAPPING
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作者 MENG Zhiqing(Department of Computer Science, Xiangtan University, Hunan 411105 Department of Applied Mathematics Xidian University, Xi,an 710071, China)HU Yuda(Department of Applied Mathematics, Shanghai Jiao Tong University, Shanghai 200030, China) 《Systems Science and Mathematical Sciences》 SCIE EI CSCD 2000年第3期327-332,共6页
In this paper, we introduce the concepts of the conesweak subdifferential and the cone-weak direction derivative of convex set-valued mapping in a locally convex topological vector space. We study the relationship bet... In this paper, we introduce the concepts of the conesweak subdifferential and the cone-weak direction derivative of convex set-valued mapping in a locally convex topological vector space. We study the relationship between them and obtain some important results. 展开更多
关键词 set-valued mapping cone-weak SUBGRADIENT cone-weak SUBDIFFERENTIAL coneweak direction DERIVATIVE
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Iterative Approximation with Errors for Generalized Set-Valued Strongly Accretive Mapping in Banach Spaces
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作者 张勇 《Journal of Southwest Jiaotong University(English Edition)》 2007年第1期70-74,共5页
A new concept of generalized set-valued strongly accretive mappings in Banach spaces was given and some strong convergence theorems of Ishikawa and Mann iterative process with errors approximation methods by Huang et ... A new concept of generalized set-valued strongly accretive mappings in Banach spaces was given and some strong convergence theorems of Ishikawa and Mann iterative process with errors approximation methods by Huang et al. was proved. The results presented in this paper improve and extend the earlier results obtained by Huang et al. 展开更多
关键词 Generalized set-valued strongly accretive mappings Ishikawa and Mann iterative processes with errors q-Uniformly Smooth Banach spaces Generalized duality mapping
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New Results on System of Generalized Quasi-Ky Fan Inequalities with Set-Valued Mappings in Topological Semilattice Spaces
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作者 NGUYEN The Vinh PHAM Thi Hoai 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2016年第6期1585-1595,共11页
Under new assumptions,this paper obtains some extended versions of Ky Fan type inequality for a family of C-continuous set-valued mappings in the setting of topological semilattices.The obtained results are new and di... Under new assumptions,this paper obtains some extended versions of Ky Fan type inequality for a family of C-continuous set-valued mappings in the setting of topological semilattices.The obtained results are new and different from the corresponding known results in the literature.Some special cases of the main result are also discussed.Some examples are given to illustrate the results. 展开更多
关键词 C△-quasiconvex (quasiconcave) Fan-Browder fixed point theorem set-valued Ky Faninequality topological semilattice upper (lower) C-continuous.
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磁共振T1rho序列、T2 mapping技术在膝关节早期软骨退变早期诊断中的评估价值 被引量:1
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作者 唐毅 张辉 +1 位作者 黄恺 黎本丰 《中国CT和MRI杂志》 2024年第4期163-165,共3页
目的探讨磁共振T1rho序列、T2 mapping技术在膝关节早期软骨退变早期诊断中的评估价值。方法选取2020年1月至2022年11月在我院治疗的110例膝关节早期软骨退变患者(观察组),按照疾病严重程度分为轻度退变组及重度退变组,另选取同期在我... 目的探讨磁共振T1rho序列、T2 mapping技术在膝关节早期软骨退变早期诊断中的评估价值。方法选取2020年1月至2022年11月在我院治疗的110例膝关节早期软骨退变患者(观察组),按照疾病严重程度分为轻度退变组及重度退变组,另选取同期在我院进行体检的64例健康者为对照组,受试者均行磁共振T1rho序列、T2 mapping技术扫描,测量受试者T2值及T1ρ值,探讨磁共振T1rho序列、T2 mapping技术在膝关节早期软骨退变早期诊断中的评估价值。结果观察组股骨外侧面、股骨内侧面、胫骨外侧面、胫骨内侧面、髋骨面T2值均明显高于对照组(P<0.05),重度退变亚组患者股骨外侧面、股骨内侧面、胫骨外侧面、胫骨内侧面、髋骨面T2值显著高于轻度退变者(P<0.05);观察组股骨内踝负重区、股骨内踝非负重区、股骨外踝负重区、股骨外踝非负重区、胫骨外侧平台区、胫骨内侧平台区、髌后软骨区磁共振T1ρ值明显高于对照组(P<0.05),重度退变亚组患者股骨内踝负重区、股骨内踝非负重区、股骨外踝负重区、股骨外踝非负重区、胫骨外侧平台区、胫骨内侧平台区、髌后软骨区磁共振T1ρ值明显高于轻度退变亚组患者(P<0.05);磁共振T1rho序列在膝关节早期软骨退变中早期诊断及严重程度评估中的的诊断ROC值及特异度明显高于T2 mapping技术(P<0.05),但后者具有更高的敏感度(P<0.05)。结论磁共振T1rho序列、T2 mapping技术均能有效反映膝关节早期软骨退变中软骨组织学成分变化情况,还可为膝关节软骨退变严重程度评估提供客观依据,二者具有一定互补价值。 展开更多
关键词 磁共振T1rho序列 T2 mapping技术 膝关节 早期软骨退变 诊断
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MR T2^(*)mapping成像技术定量评价腰椎小关节炎软骨损伤 被引量:1
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作者 陈吉 张晨 +1 位作者 张濒 黄磊涛 《中国组织工程研究》 CAS 北大核心 2024年第30期4866-4870,共5页
背景:腰椎小关节炎是引起下腰痛的一个主要原因,目前主要依靠MRI进行初步定性诊断,但仍有一定漏诊、误诊的概率发生,因此MR T2^(*)mapping成像技术有望成为定量检查腰椎小关节炎软骨损伤的重要检测手段。目的:探讨MR T2^(*)mapping成像... 背景:腰椎小关节炎是引起下腰痛的一个主要原因,目前主要依靠MRI进行初步定性诊断,但仍有一定漏诊、误诊的概率发生,因此MR T2^(*)mapping成像技术有望成为定量检查腰椎小关节炎软骨损伤的重要检测手段。目的:探讨MR T2^(*)mapping成像技术在定量分析腰椎小关节炎软骨损伤退变中的应用价值。方法:收集南京医科大学第四附属医院2020年4月至2022年3月门诊或住院合并下腰痛共110例患者,设为病例组;同时招募无症状志愿者80例,设为对照组。对所有纳入对象L1-S1的小关节行3.0 T MR扫描,获取T2^(*)mapping横断位图像和T2WI图像,分别对所有小关节软骨进行Weishaupt分级及T2^(*)值测量,收集数据并行统计学分析。不同小关节Weishaupt分级之间小关节软骨T2^(*)值比较采用单因素方差分析。结果与结论:①经统计分析发现,病例组腰椎小关节软骨T2^(*)值(17.6±1.5)ms明显较对照组(21.4±1.3)ms降低,差异有显著性意义(P<0.05);②在病例组中,随着腰椎小关节Weishaupt分级增加,小关节软骨T2^(*)值也呈逐渐下降趋势,且这种差异有显著性意义(P<0.05);③提示T2^(*)mapping能够较好地显示腰椎小关节软骨损伤的早期病理变化,腰椎小关节软骨的T2^(*)值能够定量评估腰椎小关节的软骨损伤程度;T2^(*)mapping成像技术能为影像学诊断腰椎小关节炎软骨早期损伤提供很好的理论依据,具有重要的临床应用价值。 展开更多
关键词 腰椎小关节炎 T2^(*)mapping T2^(*)值 小关节软骨退变 下腰痛
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