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Adaptive XML to relational mapping: an integrated approach 被引量:3
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作者 Tian-lei HU Gang CHEN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第6期758-769,共12页
Storing and querying XML (eXtensible Markup Language) data in relational form can exploit various services offered by modern relational database management systems (RDBMSs). Due to structural complexity of XML, there ... Storing and querying XML (eXtensible Markup Language) data in relational form can exploit various services offered by modern relational database management systems (RDBMSs). Due to structural complexity of XML, there are many equivalent relational mapping schemes for the same XML data and queries. In this paper, we propose the adaptive XML to relational mapping (AX2RM) system, which considers finding optimal XML to relational (X2R) mapping as four separate but correlated procedures: logical database design, data scale estimation, workload transformation, and physical database design. We view the whole process as an autonomic computing problem and formalize the adaptive X2R mapping problem. Search spaces for each procedure are investigated individually, and five approaches for finding the optimal mapping are studied. We propose an integrated approach with greedy pruning (IT-GP), which views the mapping procedures as a whole and exploits heuristic rules in each procedure to prune impossible mappings as early as possible. Evaluation of these approaches shows the validity and high efficiency of IT-GP. 展开更多
关键词 XML XML to relational (X2R) mapping Autonomic computing
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Ontology mapping approach based on set & relation theory and OCL 被引量:1
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作者 钱鹏飞 张申生 刘英华 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第4期498-504,共7页
An ontology mapping approach based on set & relation theory and OCL is introduced,then an ontology mapping meta-model is established which is composed of ontology related elements,mapping related elements and defi... An ontology mapping approach based on set & relation theory and OCL is introduced,then an ontology mapping meta-model is established which is composed of ontology related elements,mapping related elements and definition rule related elements.This ontology mapping meta-model can be regarded as a unified mechanism to realize different kinds of ontology mappings.The powerful computation capability of set and relation theory and the flexible expressive capability of OCL can be used in the computation of ontology mapping meta-model to realize the unified mapping among different ontology models.Based on the mapping meta-model,a general mapping management framework is developed to provide a common mapping storage mechanism,some mapping APIs and mapping rule APIs. 展开更多
关键词 ONTOLOGY mapping meta-model set and relation theory OCL mapping management
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THE MAPPING RELATION AMONG SOLUTION OF SOME NONLINEAR EQUATIONS 被引量:1
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作者 倪光炯 楼森岳 《Acta Mathematica Scientia》 SCIE CSCD 1989年第2期131-141,共11页
Among the solutions of three kinds of nonlinear equations in one dimensional systems, cubic nonlinear Klein-Gordon (including Φ~4), Sine-Gordon and double Sine-Gordon, some mapping relations exist. When a solution of... Among the solutions of three kinds of nonlinear equations in one dimensional systems, cubic nonlinear Klein-Gordon (including Φ~4), Sine-Gordon and double Sine-Gordon, some mapping relations exist. When a solution of any one equation is known, so are the other two. 展开更多
关键词 DSG THE mapping relation AMONG SOLUTION OF SOME NONLINEAR EQUATIONS
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Research on the Mapping Technology of CIM and Relational Database in Power Grid
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作者 赵婉婷 王滨 《科技信息》 2011年第7期222-223,共2页
With the development of electric power industry,the requirement of information sharing and application integration between each application system is salience.To realize the real "sharing information,data mainten... With the development of electric power industry,the requirement of information sharing and application integration between each application system is salience.To realize the real "sharing information,data maintenance uniform",and effectively eliminate "island of information",a standard,open information model of power system should be followed urgently by different systems,and a common data interface should be provided.The Common Information Model(CIM) proposed by standard of IEC-61970 solve the problem effectively.The characteristics of the CIM Model and relational database of power system are analyzed,a mapping method between CIM model based on standard of IEC61970 and relational database is proposed,and corresponding problems between object-oriented model and the relational model are solved flexiblely. 展开更多
关键词 数据库 CIM GIS 地理信息系统
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QoS-oriented service composition based on mapping relation tree
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作者 张英 刘晓明 +1 位作者 王智学 陈立 《Journal of Central South University》 SCIE EI CAS 2012年第8期2194-2202,共9页
Service composition is a hot and active research area in service-oriented computing which has gained great momentum. An quality of service (QoS) oriented and tree-based approach was proposed to implement service compo... Service composition is a hot and active research area in service-oriented computing which has gained great momentum. An quality of service (QoS) oriented and tree-based approach was proposed to implement service composition efficiently. Firstly, service descriptions were transformed to mapping relations which denote the association between input and output concepts. Then, the service composition problems were resolved by building mapping relation tree dynamically based on the divide and conquer method, and all mapping relation trees were combined without redundant branch to obtain the composition scheme. Finally, the optimal composition scheme was chosen based on quality of service attributes including the preference of service request. Experiment results illustrate that this method can improve the composition efficiency and reduce the searching time by increasing the number of services in repository. 展开更多
关键词 service composition quality of service mapping relation tree divide and conquer
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An Approach for Automatically Generating R2RML-Based Direct Mapping from Relational Databases
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作者 Mohamed A.G. Hazber Ruixuan Li +1 位作者 Guandong Xu Khaled M. Alalayah 《国际计算机前沿大会会议论文集》 2016年第1期41-44,共4页
For integrating relational databases (RDBs) into semantic web applications, the W3C RDB2RDF Working Group recommended two approaches, Direct Mapping (DM) and R2RML. The DM provides a set of mapping rules according to ... For integrating relational databases (RDBs) into semantic web applications, the W3C RDB2RDF Working Group recommended two approaches, Direct Mapping (DM) and R2RML. The DM provides a set of mapping rules according to RDB schema, while the R2RML allows users to manually define mappings according to existing target ontology. The major problem to use R2RML is the effort for creating R2RML mapping documents manually. This may lead to appearance of many mistakes in the R2RML documents and requires domain experts. In this paper, we propose and implement an approach to generate an R2RML mapping documents automatically from RDB schema. The R2RML mapping reflects the behavior of the DM specification and allows any R2RML parser to generate a set of RDF triples from relational data.The input of generating approach is DBsInfo class that automatically generated from relational schema. An experimental prototype is developed and shows the effectiveness of our approach algorithms. 展开更多
关键词 relationAL DATABASE to RESOURCE DESCRIPTION FRAMEWORK (RDB2RDF) Direct mapping R2RML relationAL DATABASE RESOURCE DESCRIPTION FRAMEWORK (RDF)
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Fuzzy topological relations between fuzzy spatial objects 被引量:2
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作者 唐新明 Wolfgang Kainz 《测绘科学》 CSCD 北大核心 2006年第S1期64-68,共5页
Fuzziness is an internal property of spatial objects.How to model fuzziness of a spatial object is a main task of next generation GIS.This paper proposes basic fuzzy spatial object types based on fuzzy topology.These ... Fuzziness is an internal property of spatial objects.How to model fuzziness of a spatial object is a main task of next generation GIS.This paper proposes basic fuzzy spatial object types based on fuzzy topology.These object types are the natural extension of current nonfuzzy spatial object types.A fuzzy cell complex structure is defined for modeling fuzzy regions,lines and points.Furthermore,fuzzy topological relations between these fuzzy spatial objects are formalized based on the 9intersection approach.This model can be implemented for GIS applications due to its scientific theory basis. 展开更多
关键词 GIS FUZZY TOPOLOGICAL relationS FUZZY SPATIAL objectS
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基于J2EE的O/R(Object-Relation)映射方案研究
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作者 娄锋 孙涌 《计算机应用与软件》 CSCD 北大核心 2008年第3期105-107,共3页
对象模型和关系模型是两种完全不同的模式,在开发中如何实现对象到关系的映射是一个关键的问题,分析了对象关系映射不匹配的各个方面,以及当前的各种持久化解决方案,并重点分析了透明对象关系映射的特点,最后对如何实现对象关系映射的... 对象模型和关系模型是两种完全不同的模式,在开发中如何实现对象到关系的映射是一个关键的问题,分析了对象关系映射不匹配的各个方面,以及当前的各种持久化解决方案,并重点分析了透明对象关系映射的特点,最后对如何实现对象关系映射的关键技术进行了研究。 展开更多
关键词 O/R 映射 持久化 聚合
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Fundamental Theories of Spatial Similarity Relations in Multi-scale Map Spaces 被引量:18
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作者 YAN Haowen 《Chinese Geographical Science》 SCIE CSCD 2010年第1期18-22,共5页
Similarity relation is one of the spatial relations in the community of geographic information science and cartography.It is widely used in the retrieval of spatial databases, the recognition of spatial objects from i... Similarity relation is one of the spatial relations in the community of geographic information science and cartography.It is widely used in the retrieval of spatial databases, the recognition of spatial objects from images, and the description of spatial features on maps.However, little achievements have been made for it by far.In this paper, spatial similarity relation was put forward with the introduction of automated map generalization in the construction of multi-scale map databases;then the definition of spatial similarity relations was presented based on set theory, the concept of spatial similarity degree was given, and the characteristics of spatial similarity were discussed in detail, in-cluding reflexivity, symmetry, non-transitivity, self-similarity in multi-scale spaces, and scale-dependence.Finally a classification system for spatial similarity relations in multi-scale map spaces was addressed.This research may be useful to automated map generalization, spatial similarity retrieval and spatial reasoning. 展开更多
关键词 similarity relation spatial relation multi-scale map spaces
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Study on Logical Relations amongUnderground Survey Objects Using Quotient Topological Space 被引量:1
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作者 陈宜金 《International Journal of Mining Science and Technology》 SCIE EI 1997年第2期7-10,共4页
A soitable data model and data structure make underground survey objects maintained and operated easier. This paper gives a formal definition for underground survey objects. By making use of the quotient topological s... A soitable data model and data structure make underground survey objects maintained and operated easier. This paper gives a formal definition for underground survey objects. By making use of the quotient topological space, the author studies the logical relations among underground survey objects, a partiallyordered space uuder some conditions. An example is given to show the data model’s possible applications. 展开更多
关键词 UNDERGROUND SURVEY objectS QUOTIENT TOPOLOGICAL space logical relation
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Iterative convergence theorems for maximal monotone operators and relatively nonexpansive mappings 被引量:5
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作者 WEI Li SU Yong-fu ZHOU Hai-yun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第3期319-325,共7页
In this paper, some iterative schemes for approximating the common element of the set of zero points of maximal monotone operators and the set of fixed points of relatively nonexpansive mappings in a real uniformly sm... In this paper, some iterative schemes for approximating the common element of the set of zero points of maximal monotone operators and the set of fixed points of relatively nonexpansive mappings in a real uniformly smooth and uniformly convex Banach space are proposed. Some strong convergence theorems are obtained, to extend the previous work. 展开更多
关键词 maximal monotone operator relatively nonexpansive mapping strong convergence zero point fixed point
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DEALING WITH SPATIAL RELATIONS FOR SPATIAL OBJECTS WITH RANDOMNESS IN GIS 被引量:2
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作者 DENG MinLI ChengmingLIU Wenbao 《Geo-Spatial Information Science》 2001年第4期43-48,共6页
To design retrieval algorithm of spatial relations for spatial objects with randomness in GIS,this paper builds up the membership functions based on set theory idea,used for determination of topological spatial relati... To design retrieval algorithm of spatial relations for spatial objects with randomness in GIS,this paper builds up the membership functions based on set theory idea,used for determination of topological spatial relations between random objects,such as between point and point,point and line or polygon,which provides theoretical basis for retrieving spatial relations between certain and random objects.Finally,this paper interprets detailed methods and steps of realizing them by means of some simple examples under the GIS’s environment. 展开更多
关键词 spatial object RANDOMNESS topologic relations
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Evaluation and mapping of relative sensitivity of the terrestrial ecosystems to acidic deposition in Fujian 被引量:2
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作者 樊后保 梁慧燕 +1 位作者 林德喜 陈世品 《Journal of Forestry Research》 CAS CSCD 2000年第1期13-18,共6页
Based on the semi-quantitative approach, four environmental factors of sites (i.e. bedrock lithology, soil type, land use, and rainfall) were categorized, weighted and combined to determine and assess the relative sen... Based on the semi-quantitative approach, four environmental factors of sites (i.e. bedrock lithology, soil type, land use, and rainfall) were categorized, weighted and combined to determine and assess the relative sensitivity of the terrestrial ecosystems to acidic deposition in Fujian Province. Then the factors have been digitized and combined to assign an overall value for each mesh square (16.77 km×18.39 km) by using the geographic information system (GIS) The results indicated that the most sensitive area in Fujian was mainly located in the southeast, and the least: ensitive area was distributed sporadically in the east along the coast. Due to slow weathering rate of siliceous rocks, acid to weakly acid reactions of the soils, along with the greater percent of coniferous forests, more than 80 percent of the total area exhibits higher sensitivity classes (4–7). 展开更多
关键词 Acidic deposition Terrestrial ecosystem relative sensitivity Mesh map
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Rules-based object-relational databases ontology construction 被引量:6
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作者 Chen Jia Wu Yue 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第1期211-215,共5页
To solve the problems of shaving and reusing information in the information system, a rules-based ontology constructing approach from object-relational databases is proposed. A 3-tuple ontology constructing model is p... To solve the problems of shaving and reusing information in the information system, a rules-based ontology constructing approach from object-relational databases is proposed. A 3-tuple ontology constructing model is proposed first. Then, four types of ontology constructing rules including class, property, property characteristics, and property restrictions ave formalized according to the model. Experiment results described in Web ontology language prove that our proposed approach is feasible for applying in the semantic objects project of semantic computing laboratory in UC Irvine. Our approach reduces about twenty percent constructing time compared with the ontology construction from relational databases. 展开更多
关键词 ontology constructing semantic objects object-relational databases RULES ONTOLOGY Web ontologylanguage.
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Major Gene Identification and Quantitative Trait Locus Mapping for YieldRelated Traits in Upland Cotton(Gossypium hirsutum L.) 被引量:8
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作者 XIA Zhe ZHANG Xin +4 位作者 LIU Yang-yang JIA Zi-fang ZHAO Hai-hong LI Cheng-qi WANG Qing-lian 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第2期299-309,共11页
Segregation analysis of the mixed genetic model of major gene plus polygene was used to identify the major genes for cotton yield-related traits using six generations P1, P2, F1, B1, B2, and F2 generated from the cros... Segregation analysis of the mixed genetic model of major gene plus polygene was used to identify the major genes for cotton yield-related traits using six generations P1, P2, F1, B1, B2, and F2 generated from the cross of Baimian 1 x TM-1. In addition to boll size and seed index, the major genes for the other five traits were detected: one each for seed yield, lint percentage, boll number, lint index; and two for lint yield. Quantitative trait locus/loci (QTL) mapping was performed in the F2 and F2:3 populations of above cross through molecular marker technology, and a total of 50 QTL (26 suggestive and 24 significant) for yield-related traits were detected. Four common QTL were discovered: qLP-3b(F2)/qLP-3(F2:3) and qLP-19b (F2)/qLP-19(F2:3) for lint percentage, qBN-17(F2)/qBN-17(F2:3) for boll number, and qBS-26b(F2)/qBS-26(F2:3) for boll size. Especially, qLP- 3b(Fz)/qLP-3(F2:3), not only had LOD scores 〉3 but also exceeded the permutation threshold (5.13 and 5.29, respectively), correspondingly explaining 23.47 and 29.55% of phenotypic variation. This QTL should be considered preferentially in marker assisted selection (MAS). Segregation analysis and QTL mapping could mutually complement and verify, which provides a theoretical basis for genetic improvement of cotton yield-related traits by using major genes (QTL). 展开更多
关键词 major gene segregation analysis QTL mapping yield-related traits upland cotton
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Aircraft Landing Gear Control with Multi-Objective Optimization Using Generalized Cell Mapping 被引量:3
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作者 孙建桥 贾腾 +3 位作者 熊夫睿 秦志昌 吴卫国 丁千 《Transactions of Tianjin University》 EI CAS 2015年第2期140-146,共7页
This paper presents a numerical algorithm tuning aircraft landing gear control system with three objectives,including reducing relative vibration, reducing hydraulic strut force and controlling energy consumption. Sli... This paper presents a numerical algorithm tuning aircraft landing gear control system with three objectives,including reducing relative vibration, reducing hydraulic strut force and controlling energy consumption. Sliding mode control is applied to the vibration control of a simplified landing gear model with uncertainty. A two-stage generalized cell mapping algorithm is applied to search the Pareto set with gradient-free scheme. Drop test simulations over uneven runway show that the vibration and force interaction can be considerably reduced, and the Pareto optimum form a tight range in time domain. 展开更多
关键词 LANDING GEAR SLIDING mode CONTROL model uncertainty MULTI-objectIVE optimization GENERALIZED cellmapping
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Multi-objective Optimal Design of Vibration Absorber with Simple Cell Mapping Algorithm 被引量:1
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作者 Jianqiao Sun Wen Zheng +2 位作者 Furui Xiong Zhichang Qin Qian Ding 《Transactions of Tianjin University》 EI CAS 2017年第5期488-492,共5页
In this paper, we investigate a multi-objective optimal design of a tuned vibration absorber for a two degrees-of-freedom linear system, in which we take white Gaussian noise as the excitation. We use the simple cell ... In this paper, we investigate a multi-objective optimal design of a tuned vibration absorber for a two degrees-of-freedom linear system, in which we take white Gaussian noise as the excitation. We use the simple cell mapping method to obtain solutions to the multi-objective optimization problem. We optimize tuned vibration absorbers in two different configurations. As our objective, we take various features of the response of the power spectrum density function. Our results show that the primary mass vibration with the optimally designed absorber has a lower peak power spectrum value. In addition, the two natural frequencies of the optimized system are further apart than in the non-optimized system, which implies that the absorber has a wider effective region in the frequency domain. © 2017, Tianjin University and Springer-Verlag GmbH Germany. 展开更多
关键词 Conformal mapping Gaussian noise (electronic) Linear systems mapping Optimal systems Optimization Power spectrum
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Experimental Evaluation of Objective Functions for Well-balanced Mapping
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作者 Chen Delai Xu Hong Zhou Ying and Zhang Defu(Department of Computer Science and Technology Nailing University, Naming 210093, P. R. China) 《Wuhan University Journal of Natural Sciences》 CAS 1996年第Z1期312-316,共5页
High performance of parallel computing on a message-passing multicomputer System relies on the balance of the workloads located on the processing elements of the System and the minimum communication ovcrheads among th... High performance of parallel computing on a message-passing multicomputer System relies on the balance of the workloads located on the processing elements of the System and the minimum communication ovcrheads among them. Mapping is the technology to partition the problem domain wellbalanced into multiple distinct execution tasks based on some measures. In mapping, a good objective function is the criterion to guarantce the distinct execution tasks equitable. In this paper, we evaluate five categories of those existed objective functions with three different problem subjects using experiments and find an objective function is much suitable for all kinds of problems. 展开更多
关键词 mapping Heuristic algorithm objective functions
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PORLES:A Parallel Object Relational Database System
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作者 Sun Yong\|qiang, Xu Shu\|ting, Zhu Feng\|hua, Lai Shu\|huaDepartment of Computer Science and Engineering, Shanghai Jiaotong University, Shanghai 200030,China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期100-109,共10页
We developed a parallel object relational DBMS named PORLES. It uses BSP model as its parallel computing model, and monoid calculus as its basis of data model. In this paper, we introduce its data model, parallel que... We developed a parallel object relational DBMS named PORLES. It uses BSP model as its parallel computing model, and monoid calculus as its basis of data model. In this paper, we introduce its data model, parallel query optimization, transaction processing system and parallel access method in detail. 展开更多
关键词 parallel object relational database BSP model data model query optimization
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A General Method for QTL Mapping in Multiple Related Populations Derived from Multiple Parents
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作者 AO Yan HU Zhi-qiu TANG Zai-xiang WANG Xue-feng XU Chen-wu 《Rice science》 SCIE 2009年第1期45-50,共6页
It's well known that incorporating some existing populations derived from multiple parents may improve QTL mapping and QTL-based breeding programs. However, no general maximum likelihood method has been available for... It's well known that incorporating some existing populations derived from multiple parents may improve QTL mapping and QTL-based breeding programs. However, no general maximum likelihood method has been available for this strategy. Based on the QTL mapping in multiple related populations derived from two parents, a maximum likelihood estimation method was proposed, which can incorporate several populations derived from three or more parents and also can be used to handle different mating designs. Taking a circle design as an example, we conducted simulation studies to study the effect of QTL heritability and sample size upon the proposed method. The results showed that under the same heritability, enhanced power of QTL detection and more precise and accurate estimation of parameters could be obtained when three F2 populations were jointly analyzed, compared with the joint analysis of any two F2 populations. Higher heritability, especially with larger sample sizes, would increase the ability of QTL detection and improve the estimation of parameters. Potential advantages of the method are as follows: firstly, the existing results of QTL mapping in single population can be compared and integrated with each other with the proposed method, therefore the ability of QTL detection and precision of QTL mapping can be improved. Secondly, owing to multiple alleles in multiple parents, the method can exploit gene resource more adequately, which will lay an important genetic groundwork for plant improvement. 展开更多
关键词 related population quantitative trait locus gene mapping maximum likelihood estimation
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