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Targeted screening and profiling of massive components of colistimethate sodium by two-dimensional-liquid chromatography-mass spectrometry based on self-constructed compound database
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作者 Xuan Li Minwen Huang +11 位作者 Yue-Mei Zhao Wenxin Liu Nan Hu Jie Zhou Zi-Yi Wang Sheng Tang Jian-Bin Pan Hian Kee Lee Yao-zuo Yuan Taijun Hang Hai-Wei Shi Hongyuan Chen 《Journal of Pharmaceutical Analysis》 2025年第2期401-410,共10页
In-depth study of the components of polymyxins is the key to controlling the quality of this class of antibiotics.Similarities and variations of components present significant analytical challenges.A two-dimensional(2... In-depth study of the components of polymyxins is the key to controlling the quality of this class of antibiotics.Similarities and variations of components present significant analytical challenges.A two-dimensional(2D)liquid chromatography-mass spectrometry(LC-MS)method was established for screening and comprehensive profiling of compositions of the antibiotic colistimethate sodium(CMS).A high concentration of phosphate buffer mobile phase was used in the first-dimensional LC system to get the components well separated.For efficient and high-accuracy screening of CMS,a targeted method based on a self-constructed high resolution(HR)mass spectrum database of CMS components was established.The database was built based on the commercial MassHunter Personal Compound Database and Library(PCDL)software and its accuracy of the compound matching result was verified with six known components before being applied to genuine sample screening.On this basis,the unknown peaks in the CMS chromatograms were deduced and assigned.The molecular formula,group composition,and origins of a total of 99 compounds,of which the combined area percentage accounted for more than 95%of CMS components,were deduced by this 2D-LC-MS method combined with the MassHunter PCDL.This profiling method was highly efficient and could distinguish hundreds of components within 3 h,providing reliable results for quality control of this kind of complex drugs. 展开更多
关键词 Colistimethate sodium 2D-LC-MS PROFILING Targeted screening Component deduction database
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Analysis and Design of Soils and Terrain Digital Database (SOTER) Management System Based on Object-Oriented Method 被引量:4
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作者 ZHANGHAITAO ZHOUYONG +2 位作者 R.V.BIRNIE A.SIBBALD RENYI 《Pedosphere》 SCIE CAS CSCD 2003年第2期111-120,共10页
A SOTER management system was developed by analyzing, designing, programming, testing, repeated proceeding and progressing based on the object-oriented method. The function of the attribute database management is inhe... A SOTER management system was developed by analyzing, designing, programming, testing, repeated proceeding and progressing based on the object-oriented method. The function of the attribute database management is inherited and expanded in the new system. The integrity and security of the SOTER database are enhanced. The attribute database management, the spatial database management and the model base are integrated into SOTER based on the component object model (COM), and the graphical user interface (GUI) for Windows is used to interact with clients, thus being easy to create and maintain the SOTER, and convenient to promote the quantification and automation of soil information application. 展开更多
关键词 component object model database model object-oriented SOTER
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Development of E-Mart Based on Object-Oriented Databases (OODB)
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作者 孙莉 汪立 刘皓霜 《Journal of Donghua University(English Edition)》 EI CAS 2002年第2期112-116,共5页
Focusing on the development of electronic-mart (e-mart) based on object-oriented databases (OODB), the concepts of integrated electronic-commerce (e-commerce) environment and e-mart are introduced, and the basic chara... Focusing on the development of electronic-mart (e-mart) based on object-oriented databases (OODB), the concepts of integrated electronic-commerce (e-commerce) environment and e-mart are introduced, and the basic characteristics of OODB Jasmine are described. In addition, the database mode and hierarchy of e-mart are discussed in detail. 展开更多
关键词 Internet E-COMMERCE e-mart object-oriented database (OODB)
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CRF:A Scheduling of Multi-Granularity Locks in Object-Oriented Database Systems
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作者 Qin Xiao & Pang Liping(Department of Computer Science, Huazhong University of Science and Technology,Wuhan 430074, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第4期51-57,共7页
This paper introduces a multi-granularity locking model (MGL) for concurrency control in object-oriented database system briefiy, and presents a MGL model formally. Four lockingscheduling algorithms for MGL are propos... This paper introduces a multi-granularity locking model (MGL) for concurrency control in object-oriented database system briefiy, and presents a MGL model formally. Four lockingscheduling algorithms for MGL are proposed in the paper. The ideas of single queue scheduling(SQS) and dual queue scheduling (DQS) are proposed and the algorithm and the performance evaluation for these two scheduling are presented in some paper. This paper describes a new idea of thescheduling for MGL, compatible requests first (CRF). Combining the new idea with SQS and DQS,we propose two new scheduling algorithms called CRFS and CRFD. After describing the simulationmodel, this paper illustrates the comparisons of the performance among these four algorithms. Asshown in the experiments, DQS has better performance than SQS, CRFD is better than DQS, CRFSperforms better than SQS, and CRFS is the best one of these four scheduling algorithms. 展开更多
关键词 Lock scheduling Multi-granularity lock Concurrency control Compatible requestsfirst Single queue scheduling Dual queue scheduling object-oriented database system
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O-O Analysis of Vehicle Body Design and Establishment of Engineering Database
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作者 陈思忠 林磊明 +1 位作者 张斌 谷中丽 《Journal of Beijing Institute of Technology》 EI CAS 1998年第2期184-189,共6页
To establish the object-oriented (O-O) engineering for vehicle body design Methods characteristics of vehicle body design data were analyzed by means of theO-Omethod The analytical results were transformed intothe eng... To establish the object-oriented (O-O) engineering for vehicle body design Methods characteristics of vehicle body design data were analyzed by means of theO-Omethod The analytical results were transformed intothe engineering databasethat canbeusedsufficiently to describe the relative information of vehicle body design data.Results TheO-Oengineeringdatabaseforvehiclebodydesignis realized and practiced in the process ofbody design for a QCJ7082 economical car. Conclusion The method is successful in trans- forming vehicle body design object into engineering database.The database supports each procedure of vehicle body design perfectly 展开更多
关键词 vehicle body design engineering database object-oriented
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ENTITY-ROLES MODEL AND OBJECT-ORIENTED KNOWLEDGE/DATA BASES
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作者 Pan Jiuhui Liu Zhimin Wang Yunyi(Department of Computer Science, Central South University of Technology, Changsha, 410083, China) 《Journal of Central South University》 SCIE EI CAS 1994年第1期74-77,共4页
A Model, called 'Entity-Roles' is proposed in this paper in which the world of Interest is viewed as some mathematical structure. With respect to this structure, a First order (three-valued) Logic Language is ... A Model, called 'Entity-Roles' is proposed in this paper in which the world of Interest is viewed as some mathematical structure. With respect to this structure, a First order (three-valued) Logic Language is constructured.Any world to be modelled can be logically specified in this Language. The integrity constraints on the database and the deducing rules within the Database world are derived from the proper axioms of the world being modelled. 展开更多
关键词 EXPERT systems data model object-oriENTATION database logic deductive QUERY
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Incremental View Computation Model for Object-Oriented Information
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作者 GuoHai-ying ZhongTing-xiu 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第3期343-347,共5页
We introduce a model to implement incremental update of views. The principle is that unless a view is accessed, the modification related to the view is not computed. This modification information is used only when vie... We introduce a model to implement incremental update of views. The principle is that unless a view is accessed, the modification related to the view is not computed. This modification information is used only when views are updated. Modification information is embodied in the classes (including inheritance classes and nesting classes) that derive the view. We establish a modify list consisted of tuples (one tuple for each view which is related to the class) to implement view update. A method is used to keep views from re-update. Key words object-oriented database - incremental computation - view-computation - engineering information system CLC number TP 391 Foundation item: Supported by the National Natural Science Foundation of China(60235025)Biography: Guo Hai-ying (1971-), female, Ph. D, research direction: CAD and engineering information system. 展开更多
关键词 object-oriented database incremental computation view-computation engineering information system
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DATABASE STRUCTURE FOR THE INTEGRATION OF RS WITH GIS BASED ON SEMANTIC NETWORK
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作者 YU Nenghai WANG Xiaogang LIU Zhengkai ZHANG Rong 《Geo-Spatial Information Science》 2001年第3期21-28,共8页
The integration of remote sensing (RS) with geographical information system (GIS) is a hotspot in geographical information science.A good database structure is important to the integration of RS with GIS,which should ... The integration of remote sensing (RS) with geographical information system (GIS) is a hotspot in geographical information science.A good database structure is important to the integration of RS with GIS,which should be beneficial to the complete integration of RS with GIS,able to deal with the disagreement between the resolution of remote sensing images and the precision of GIS data,and also helpful to the knowledge discovery and exploitation.In this paper,the database structure storing the spatial data based on semantic network is presented.This database structure has several advantages.Firstly,the spatial data is stored as raster data with space index,so the image processing can be done directly on the GIS data that is stored hierarchically according to the distinguishing precision.Secondly,the simple objects are aggregated into complex ones.Thirdly,because we use the indexing tree to depict the relationship of aggregation and the indexing pictures expressed by 2_D strings to describe the topology structure of the objects,the concepts of surrounding and region are expressed clearly and the semantic content of the landscape can be illustrated well.All the factors that affect the recognition of the objects are depicted in the factor space,which provides a uniform mathematical frame for the fusion of the semantic and non_semantic information.Lastly,the object node,knowledge node and the indexing node are integrated into one node.This feature enhances the ability of system in knowledge expressing,intelligent inference and association.The application shows that this database structure can benefit the interpretation of remote sensing image with the information of GIS. 展开更多
关键词 integration of RS with GIS database structure object-oriented semantic-oriented expert system spatial data mining
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Modeling and OLAP Cubes for Database of Ground and Municipal Water Supply
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作者 Taskeen Zaidi Annapurna Singh Vipin Saxena 《Computational Water, Energy, and Environmental Engineering》 2013年第3期77-82,共6页
Modeling plays an important role for the solution of the complex research problems. When the database became large and complex then it is necessary to create a unified model for getting the desired information in the ... Modeling plays an important role for the solution of the complex research problems. When the database became large and complex then it is necessary to create a unified model for getting the desired information in the minimum time and to implement the model in a better way. The present paper deals with the modeling for searching of the desired information from a large database by storing the data inside the three dimensional data cubes. A sample case study is considered as a real data related to the ground water and municipal water supply, which contains the data from the various localities of a city. For the demonstration purpose, a sample size is taken as nine but when it becomes very large for number of localities of different cities then it is necessary to store the data inside data cubes. A well known object-oriented Unified Modeling Language (UML) is used to create Unified class and state models. For verification purpose, sample queries are also performed and corresponding results are depicted. 展开更多
关键词 MODELING database object-oriented UNIFIED MODELING Language OLAP Data CUBES Water Supply
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OLDTNF-based evaluation method for handling recursive queries in deductive databases
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作者 陈阳军 《Science China(Technological Sciences)》 SCIE EI CAS 1998年第6期561-578,共18页
OLDTNF resolution is an important mechanism used in a Prolog interpreter. This mechanism is extended and improved for evaluating recursive queries in deductive databases. The key idea of the refinement is to distingui... OLDTNF resolution is an important mechanism used in a Prolog interpreter. This mechanism is extended and improved for evaluating recursive queries in deductive databases. The key idea of the refinement is to distinguish between two classes of lookup nodes in an OLDTNF derivation and to handle them differently. First, reduce the search space by cutting of any subtree rooted at a lookup node of the first class. Further, speed up the evaluation by processing the second class in a second phase and generate many solutions directly from the solutions already produced (and the corresponding keys of solution lists) instead of evaluating them by expanding the corresponding subtrees in terms of the new solutions stored in solution lists. 展开更多
关键词 PROLOG SLD RESOLUTION OLDTNF RESOLUTION deductive databases recursion.
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Query Optimization for Deductive Databases
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作者 周傲英 施伯乐 《Journal of Computer Science & Technology》 SCIE EI CSCD 1995年第2期134-148,共15页
A systematic, efficient compilation method for query evaluation of DeductiveDatabases (DeDB) is proposed in this paper. In order to eliminate redundancyand to minimize the potentially relevant facts, which are two key... A systematic, efficient compilation method for query evaluation of DeductiveDatabases (DeDB) is proposed in this paper. In order to eliminate redundancyand to minimize the potentially relevant facts, which are two key issues to theefficiency of a DeDB, the compilation process is decomposed into two phases.The first is the pre-compilation phase, which is responsible for the minimiza-tion of the potentially relevant facts. The second, which we refer to as thegeneral compilation phase, is responsible for the elimination of redundancy.The rule/goal graph devised by J. D. Ullman is appropriately extended andused as a uniform formalism. Two general algorithms corresponding to the twophases respectively are described intuitively and formally 展开更多
关键词 deductive database query evaluation query optimization
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Design and Implementation of a Concurrency Control Mechanism in an Object-Oriented Database System
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作者 曲云尧 田增平 +1 位作者 王宇君 施伯乐 《Journal of Computer Science & Technology》 SCIE EI CSCD 1996年第4期337-346,共10页
This paper presents a practical concurrency control mechanism - ObjectLockingin OODBMS. Object-Locking can schedule transactions, each of themcan be considered as a sequence of high level operations defined on classe... This paper presents a practical concurrency control mechanism - ObjectLockingin OODBMS. Object-Locking can schedule transactions, each of themcan be considered as a sequence of high level operations defined on classes. Bythe properties of parallelity and coatativity between high level operations,proper lock modes for each operation are desigued and the compatibility matrixis constructed. With these lock modes, phatoms are kept away from databasesand a high degree of concurrency is achieved. 展开更多
关键词 Concurrency control object-oriented database transaction management
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A Deductive Database Approach for Complex Objects
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作者 陈其明 《Journal of Computer Science & Technology》 SCIE EI CSCD 1990年第3期225-235,共11页
A deductive database approach for complex objects reasoning is proposed,which is characterized by handling predicates nesting in terms of mapping hierarchically structured rules and facts to a flattened Horn-clause im... A deductive database approach for complex objects reasoning is proposed,which is characterized by handling predicates nesting in terms of mapping hierarchically structured rules and facts to a flattened Horn-clause implementation scheme. 展开更多
关键词 RLC LPT A deductive database Approach for Complex Objects
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Concurrency Control of Single-Level Transaction in WHYMX Object-Oriented Database System
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作者 徐庆云 王能斌 《Journal of Computer Science & Technology》 SCIE EI CSCD 1992年第4期311-315,共5页
The data model of WHYMX complicates transaction management. Traditional locking method is not powerful enough to solve the new problem of concurrency control of WHYMX's transaction. This paper presents a number of... The data model of WHYMX complicates transaction management. Traditional locking method is not powerful enough to solve the new problem of concurrency control of WHYMX's transaction. This paper presents a number of concurrency control algorithms based on the extended locking method. 展开更多
关键词 mode Concurrency Control of Single-Level Transaction in WHYMX object-oriented database System
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基于动态推演的矿山采掘计划调控系统
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作者 徐小迪 郭忠平 王蕊 《煤矿安全》 CAS 北大核心 2024年第2期228-234,共7页
矿山采掘计划编制是矿山企业生产管理的一项重要工作,传统的人工编制采掘计划并不能很好地适应日益复杂的煤矿生产环境,从而导致采掘接替紧张等问题,由此,设计了基于动态推演的矿山采掘计划调控系统。系统采用动态规划法,根据采掘生产... 矿山采掘计划编制是矿山企业生产管理的一项重要工作,传统的人工编制采掘计划并不能很好地适应日益复杂的煤矿生产环境,从而导致采掘接替紧张等问题,由此,设计了基于动态推演的矿山采掘计划调控系统。系统采用动态规划法,根据采掘生产特点和要求,建立动态推演模型,计算得出合适的生产周期与每个季度所需的回采煤量,并借助GIS的数据库模型以及AutoCAD等软件实现采掘过程的动态推演;为应对生产计划不能按时完成的状况,通过设立大纲等级以及设置不同任务的连接关系,有效避免了采掘接替紧张的问题,并借助于计算机实现优化计算,进而实现矿山采掘计划的动态调控。 展开更多
关键词 矿山采掘计划 调控系统 动态推演 GIS 数据库 矿山生产管理 采掘接替
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PROLOG—DBMS系统实现中的子句间优化技术 被引量:7
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作者 李磊 左万历 李希春 《软件学报》 EI CSCD 北大核心 1995年第3期136-141,共6页
实用PROLOG—DBMS系统实现中的首要问题是要保证系统的正确性.然而,从数据库中提取冗余数据不但严重地影响系统的效率,而且影响系统的正确性.本文所提出的子句间优化技术可以解决这一问题.因为采用这一技术可以保证仅从... 实用PROLOG—DBMS系统实现中的首要问题是要保证系统的正确性.然而,从数据库中提取冗余数据不但严重地影响系统的效率,而且影响系统的正确性.本文所提出的子句间优化技术可以解决这一问题.因为采用这一技术可以保证仅从数据库中提取有用事实并且没有任何元组多于一次被提取. 展开更多
关键词 PROLOG语言 数据库 演绎数据库 子句间优化
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基于SQL Server的演绎数据库系统 被引量:7
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作者 陶世群 原锦辉 《计算机工程》 CAS CSCD 北大核心 2001年第3期33-34,共2页
分析了演绎数据库的理论基础和实现机制,重点介绍设计和实现的基于SQL Server的演绎数据库系统,对系统进行了分析和评价.
关键词 演绎数据库系统 SQL SERVER 人工智能 数学模型
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电网调度管理演绎数据库模型研究与实现 被引量:3
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作者 刘青 黄超 +1 位作者 谭振宇 程时杰 《中国电机工程学报》 EI CSCD 北大核心 1998年第6期405-407,433,共4页
本文针对传统专家系统在具有海量数据特征的电力系统的应用中存在的问题,提出了一个电网调度管理演绎数据库模型。介绍了该模型中基于关系数据模式的知识表示方法和基于查询的推理机制,并基于中文Windows环境和关系型DBMS... 本文针对传统专家系统在具有海量数据特征的电力系统的应用中存在的问题,提出了一个电网调度管理演绎数据库模型。介绍了该模型中基于关系数据模式的知识表示方法和基于查询的推理机制,并基于中文Windows环境和关系型DBMSFoxpro2.5B实现了该演绎数据库模型,实践表明该实际系统在演绎推理的有效性和可靠性方面都大为提高。 展开更多
关键词 电网调度 知识表示 演绎数据库 关系模型
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演绎数据库系统SD-DDBS的设计与实现 被引量:6
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作者 陶世群 陈晓东 《计算机工程与应用》 CSCD 北大核心 2002年第18期207-209,共3页
主要介绍了一种演绎数据库系统SD-DDBS的设计思想和实现技术,重点阐述了规则的表示及实现机制。
关键词 演绎数据库系统 SD-DDBS 设计 推理机 递归查询 规则库 人工智能
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一种基于证明树反演的安全漏洞定位方法 被引量:2
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作者 王清 郑庆华 +1 位作者 管晓宏 张哲菲 《西安交通大学学报》 EI CAS CSCD 北大核心 2007年第4期439-443,共5页
针对Web应用中普遍存在SQL注入漏洞等问题,提出了一种基于证明树反演的漏洞定位方法.该方法可对攻击产生的根源直接进行源代码的漏洞挖掘,其核心思想是:通过在脚本中反向追踪数据库操作所涉及的变量来检验其是否受到外界的影响,从而达... 针对Web应用中普遍存在SQL注入漏洞等问题,提出了一种基于证明树反演的漏洞定位方法.该方法可对攻击产生的根源直接进行源代码的漏洞挖掘,其核心思想是:通过在脚本中反向追踪数据库操作所涉及的变量来检验其是否受到外界的影响,从而达到控制数据库操作的安全隐患.实验结果表明,所提方法能够准确验证53.8%的数据库操作的安全性,对于不能做出自动判定的风险操作,则能给出变量的依赖关系.该方法适用于以各种脚本语言和数据库系统搭建的Web应用平台. 展开更多
关键词 注入漏洞 数据库操作 反演
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