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A DESIGN OF THREE-DIMENSIONAL SPATIAL DATA MODEL AND ITS DATA STRUCTURE IN GEOLOGICAL EXPLORATION ENGINEERING
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作者 Cheng Penggen Gong Jianya +1 位作者 Wang Yandong Sui Haigang 《Geo-Spatial Information Science》 1999年第1期78-85,共8页
The key to develop 3-D GISs is the study on 3-D data model and data structure. Some of the data models and data structures have been presented by scholars. Because of the complexity of 3-D spatial phenomenon, there ar... The key to develop 3-D GISs is the study on 3-D data model and data structure. Some of the data models and data structures have been presented by scholars. Because of the complexity of 3-D spatial phenomenon, there are no perfect data structures that can describe all spatial entities. Every data structure has its own advantages and disadvantages. It is difficult to design a single data structure to meet different needs. The important subject in the3-D data models is developing a data model that has integrated vector and raster data structures. A special 3-D spatial data model based on distributing features of spatial entities should be designed. We took the geological exploration engineering as the research background and designed an integrated data model whose data structures integrats vector and raster data byadopting object-oriented technique. Research achievements are presented in this paper. 展开更多
关键词 GEOLOGICAL EXPLORATION ENGINEERING GEOGRAPHIC information system three DIMENSIONAL data model data structure
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THREE DIMENSIONAL DATA STRUCTURE AND DATA MODEL
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作者 Bian Fuling Zhu Guobin +1 位作者 Li Jun Tan Xiaojun 《Geo-Spatial Information Science》 2000年第3期19-23,共5页
3D GISs were developed simultaneously in the late 1980s in a number of different disciplines.The development of these 3D GISs can not yet meet all needs for new representations and analytical tool s in 3D envir onment... 3D GISs were developed simultaneously in the late 1980s in a number of different disciplines.The development of these 3D GISs can not yet meet all needs for new representations and analytical tool s in 3D envir onments.In this paper,the data structures,especially solid-based data representa tions are introduced.Then,a typical object-oriented data model is put forth to s how a new data model.And at last,two data access methods are proposed to make th e data model clear. 展开更多
关键词 3D data structure data model
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Novel Data Structure Modeling Model based on Hierarchical Data Analysis and Parsing
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作者 Chang Liu Ting Han Changli Sun 《International Journal of Technology Management》 2017年第2期53-55,共3页
. In this article, we describe the characteristics of large-scale modeling of the theme text of this site data and important progress in recent years. Topic modeling approach has attracted wide interest in the world, ... . In this article, we describe the characteristics of large-scale modeling of the theme text of this site data and important progress in recent years. Topic modeling approach has attracted wide interest in the world, and promote a number of important data mining, development of computer vision and computational biology applications, including automatic text summaries, information retrieval, information recommendation, topic detection and tracking, natural scene understanding human action recognition and gene expression analysis. The main features of the model and the corresponding theme paper focuses on the text of this site data. Data with dynamic, high-end, multi-channel and distributed structure and the structure of the model is only part of the theme before modeling. The paper discussed in the framework of the unity of the three-dimensional Markov model of four structural features of the text of this site data modeling, and analysis of distributed computing and word combination of three-dimensional modeling topics Markov model and type fuzzy systems the possibility of applications. In addition to structural modeling for this site text data, also we discuss some of the three-dimensional Markov model energy minimization of machine learning algorithms. 展开更多
关键词 data structure modeling PARADIGM HIERARCHICAL data analysis.
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Multiresolution analysis over triangle meshes: method and data structure
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作者 唐杰 张福炎 《Journal of Southeast University(English Edition)》 EI CAS 2004年第3期279-285,共7页
A robust and efficient algorithm is presented to build multiresolution models (MRMs) of arbitrary meshes without requirement of subdivision connectivity. To overcome the sampling difficulty of arbitrary meshes, edge c... A robust and efficient algorithm is presented to build multiresolution models (MRMs) of arbitrary meshes without requirement of subdivision connectivity. To overcome the sampling difficulty of arbitrary meshes, edge contraction and vertex expansion are used as downsampling and upsampling methods. Our MRMs of a mesh are composed of a base mesh and a series of edge split operations, which are organized as a directed graph. Each split operation encodes two parts of information. One is the modification to the mesh, and the other is the dependency relation among splits. Such organization ensures the efficiency and robustness of our MRM algorithm. Examples demonstrate the functionality of our method. 展开更多
关键词 ALGORITHMS Computer aided design Computer aided manufacturing data structures GEOMETRY Mathematical models Robustness (control systems)
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Hydraulic metal structure health diagnosis based on data mining technology 被引量:3
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作者 Guang-ming Yang Xiao Feng Kun Yang 《Water Science and Engineering》 EI CAS CSCD 2015年第2期158-163,共6页
In conjunction with association rules for data mining, the connections between testing indices and strong and weak association rules were determined, and new derivative rules were obtained by further reasoning. Associ... In conjunction with association rules for data mining, the connections between testing indices and strong and weak association rules were determined, and new derivative rules were obtained by further reasoning. Association rules were used to analyze correlation and check consistency between indices. This study shows that the judgment obtained by weak association rules or non-association rules is more accurate and more credible than that obtained by strong association rules. When the testing grades of two indices in the weak association rules are inconsistent, the testing grades of indices are more likely to be erroneous, and the mistakes are often caused by human factors. Clustering data mining technology was used to analyze the reliability of a diagnosis, or to perform health diagnosis directly. Analysis showed that the clustering results are related to the indices selected, and that if the indices selected are more significant, the characteristics of clustering results are also more significant, and the analysis or diagnosis is more credible. The indices and diagnosis analysis function produced by this study provide a necessary theoretical foundation and new ideas for the development of hydraulic metal structure health diagnosis technology. 展开更多
关键词 Hydraulic metal structure Health diagnosis data mining technology Clustering model Association rule
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Data Logic Structure and Key Technologies on Intelligent High-precision Map 被引量:12
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作者 Jingnan LIU Jiao ZHAN +2 位作者 Chi GUO Tingting LEI Ying LI 《Journal of Geodesy and Geoinformation Science》 2020年第3期1-17,共17页
Taking autonomous driving and driverless as the research object,we discuss and define intelligent high-precision map.Intelligent high-precision map is considered as a key link of future travel,a carrier of real-time p... Taking autonomous driving and driverless as the research object,we discuss and define intelligent high-precision map.Intelligent high-precision map is considered as a key link of future travel,a carrier of real-time perception of traffic resources in the entire space-time range,and the criterion for the operation and control of the whole process of the vehicle.As a new form of map,it has distinctive features in terms of cartography theory and application requirements compared with traditional navigation electronic maps.Thus,it is necessary to analyze and discuss its key features and problems to promote the development of research and application of intelligent high-precision map.Accordingly,we propose an information transmission model based on the cartography theory and combine the wheeled robot’s control flow in practical application.Next,we put forward the data logic structure of intelligent high-precision map,and analyze its application in autonomous driving.Then,we summarize the computing mode of“Crowdsourcing+Edge-Cloud Collaborative Computing”,and carry out key technical analysis on how to improve the quality of crowdsourced data.We also analyze the effective application scenarios of intelligent high-precision map in the future.Finally,we present some thoughts and suggestions for the future development of this field. 展开更多
关键词 intelligent high-precision map information transmission model data logic structure user model computing mode edge-cloud collaboration
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Specification and Verification for Semi-Structured Data
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作者 CHEN Tao-lue HAN Ting-ting LU Jian 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期107-112,共6页
Tree logic, inherited from ambient logic, is introduced as the formal foundation of related programming language and type systems, In this paper, we introduce recursion into such logic system, which can describe the t... Tree logic, inherited from ambient logic, is introduced as the formal foundation of related programming language and type systems, In this paper, we introduce recursion into such logic system, which can describe the tree data more dearly and concisely. By making a distinction between proposition and predicate, a concise semantics interpretation for our modal logic is given. We also develop a model checking algorithm for the logic without △ operator. The correctness of the algorithm is shown. Such work can be seen as the basis of the semi-structured data processing language and more flexible type system. 展开更多
关键词 semi structured data tree logic FIXPOINT model checking algorithm
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A MODEL IDENTIFICATION METHOD OF VIBRATING STRUCTURES FROM INCOMPLETE MODAL INFORMATION
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作者 郑小平 姚振汉 蘧时胜 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第5期971-976,共6页
The accurate mathematical models for complicated structures are verydifficult to construct.The work presented here provides an identification method for estimating the mass, damping , and stiffness matrices of linear ... The accurate mathematical models for complicated structures are verydifficult to construct.The work presented here provides an identification method for estimating the mass, damping , and stiffness matrices of linear dynamical systems from incompleteexperimental data. The mass, stiffness, and damping matrices are assumed to be real,symmetric, and positive definite. The partial set of experimental complex eigenvalues and corresponding eigenvectors are given. In the proposed method the least squaresalgorithm is combined with the iteration technique to determine systems identified matrices and corresponding design parameters. several illustrative examples, are presented to demonstrate the reliability of the proposed method .It is emphasized thatthe mass, damping and stiffness martices can be identified simultaneously. 展开更多
关键词 vibrating structures model identification incompleteexperiemntal modal data the least squares method iteration technique
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A MODEL IDENTIFICATION METHOD OF VIBRATING STRUCTURES FROM INCOMPLETE MODAL INFORMATION
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作者 郑小平 姚振汉 蘧时胜 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第10期971-976,共6页
The accurate mathematical models for complicated structures are very difficult to construct.The work presented here provides an identification method for estimating the mass.damping,and stiffness matrices of linear dy... The accurate mathematical models for complicated structures are very difficult to construct.The work presented here provides an identification method for estimating the mass.damping,and stiffness matrices of linear dynamical systems from incomplete experimental data.The mass,stiffness and damping matrices are assumed to be real,symmetric,and positive definite The partial set of experimental complex eigenvalues and corresponding eigenvectors are given.In the proposed method the least squares algorithm is combined with the iteration technique to determine systems identified matrices and corresponding design parameters.Seeveral illustative examples,are presented to demonstrate the reliability of the proposed method .It is emphasized that the mass,damping and stiffness matrices can be identified simultaneously. 展开更多
关键词 vibrating structures model identification incomplete experiemntal modal data the least squares method iteration technique
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GRAPHICS DATA STRUCTURES IN MICROCOMPUTER AIDED DESIGN FOR OPEN PIT PLANNING
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作者 吴力心 《Journal of China University of Mining and Technology》 1991年第1期88-96,共9页
This paper discribes the importance and necessity of the study on the data structures for displaying the mining field using the interactive technology in open pit design and planning,based upon the grid block model. T... This paper discribes the importance and necessity of the study on the data structures for displaying the mining field using the interactive technology in open pit design and planning,based upon the grid block model. The commonly used data structures--rectangular array structure and quadtree structure ,are analyzed. Two compressed data structures--compressed circular link array structure and compressed doubly-linked circular array structure,are proposed,which are much more suitable for displaying the regularly gridded block model. When the two compressed data structures are adopted,the storage space can be tremendously saved and the algorithms are simple,while the requirements of the accuracy and the manipulating speed will be both satisfied for the interactive open pit short range plan formulation. 展开更多
关键词 data structure open bit planning .deposit model GRAPHICS
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Economic Growth and Interaction between Financial and Industrial Structure - Empirical Analysis on Provincial Panel Data
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作者 Fangying Yao 《经济管理学刊(中英文版)》 2019年第1期58-74,共17页
In recent years, China's economic growth speed has been slowing down, leading to the problems of overcapacity and unbalanced regional economic development, and the mismatch between industrial and financial structu... In recent years, China's economic growth speed has been slowing down, leading to the problems of overcapacity and unbalanced regional economic development, and the mismatch between industrial and financial structure is becoming intense. Therefore, this paper, starting with the relationship among economic growth, industrial structure and financial structure, summarizes the research by the former scholars. On this basis, by using data of 31 provincial panel data in China from 2007 to 2016, the article aims to find out the relationship between the industrial structure and economic growth, the relationship between the financial structure and economic growth and the relationship between the interaction of financial and industrial structure and economic growth. Finally, the corresponding policy recommendations are obtained following the systematical empirical conclusions. The conclusions of this paper are as follows:(1) developing indirect financing mode can effectively drive China's economic growth.(2) continuing to develop the second industry can play a catalytic role in the economic growth in most areas of China.(3) the interaction between the financial structure and the industrial structure can promote the economic growth significantly. However, the matching effect of the financial structure and industrial structure in China has not been completely formed, and the industrial upgrading should be guided to be structurally reformed through the policy. 展开更多
关键词 Industrial structure FINANCIAL structure ECONOMIC Growth Panel data GLS model
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Research on the Structured Data Mining Algorithm and the Applications on Machine Learning Field
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作者 Xiaodui Deng 《International Journal of Technology Management》 2016年第1期82-84,共3页
In this paper, we conduct research on the structured data mining algorithm and applications on machine learning field. Various fields due to the advancement of informatization and digitization, a lot of multi-source a... In this paper, we conduct research on the structured data mining algorithm and applications on machine learning field. Various fields due to the advancement of informatization and digitization, a lot of multi-source and heterogeneous data distributed storage, in order to achieve the sharing, we must solve from the storage management to the interoperability of a series of mechanism, the method and implementation technology. Unstructured data does not have strict structure, therefore, compared with structured information that is more difficult to standardization, with management more difficult. According to these characteristics, the large capacity of unstructured data or using files separately store, is stored in the database index of similar pointer. Under this background, we propose the new idea on the structured data mining algorithm that is meaningful. 展开更多
关键词 data Mining structureD APPLICATIONS Machine Learning model Analysis.
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Open Volumetric Mesh-An Efficient Data Structure for Tetrahedral and Hexahedral Meshes
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作者 XIAN Chu-hua LI Gui-qing GAO Shu-ming 《Computer Aided Drafting,Design and Manufacturing》 2013年第3期23-27,共5页
This work introduces a scalable and efficient topological structure for tetrahedral and hexahedral meshes. The design of the data structure aims at maximal flexibility and high performance. It provides a high scalabil... This work introduces a scalable and efficient topological structure for tetrahedral and hexahedral meshes. The design of the data structure aims at maximal flexibility and high performance. It provides a high scalability by using hierarchical representa-tions of topological elements. The proposed data structure is array-based, and it is a compact representation of the half-edge data structure for volume elements and half-face data structure for volumetric meshes. This guarantees constant access time to the neighbors of the topological elements. In addition, an open-source implementation named Open Volumetric Mesh (OVM) of the pro-posed data structure is written in C++ using generic programming concepts. 展开更多
关键词 tetrahedral mesh hexahedral mesh geometry modeling data structure generic programming
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Accuracy Comparison of Data Imputation Estimation Using Structural Equation Modeling Between Constrained and Unconstrained Approaches
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作者 Narong Phothi Somchai Prakancharoen 《通讯和计算机(中英文版)》 2012年第3期297-302,共6页
关键词 结构方程模型 测量精度 M估计 矿产资源 归责 美国加州大学 测试数据 网上数据库
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A 3-DIMENSIONAL DATA MODEL FOR VISUALIZING CLOVERLEAF JUNCTION IN A CITY MODEL 被引量:6
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作者 Chen Jun Sun Min Zhou Qiming 《Geo-Spatial Information Science》 1999年第1期9-15,共7页
The research work has been seldom done about cloverleaf junction expression in a 3-dimensional city model (3DCM). The main reason is that the cloverleaf junction is often in a complex and enormous construction. Its ma... The research work has been seldom done about cloverleaf junction expression in a 3-dimensional city model (3DCM). The main reason is that the cloverleaf junction is often in a complex and enormous construction. Its main body is bestraddle in air,and has aerial intersections between its parts. This complex feature made cloverleaf junction quite different from buildings and terrain, therefore, it is difficult to express this kind of spatial objects in the same way as for buildings and terrain. In this paper,authors analyze spatial characteristics of cloverleaf junction, propose an all-constraint points TIN algorithm to partition cloverleaf junction road surface, and develop a method to visualize cloverleaf junction road surface using TIN. In order to manage cloverleaf junction data efficiently, the authors also analyzed the mechanism of 3DCM data management, extended BLOB type in relational database, and combined R-tree index to manage 3D spatial data. Based on this extension, an appropriate data 展开更多
关键词 3-dimensional CITY model (3DCM) GIS cloverleaf JUNCTION data structure dataBASE
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Density structure of the crust in the Emeishan large igneous province revealed by the Lijiang-Guiyang gravity profile 被引量:1
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作者 Xi Zhang Peng Wang +3 位作者 Tao Xu Yun Chen José Badal JiWen Teng 《Earth and Planetary Physics》 2018年第1期74-81,共8页
The Emeishan large igneous province(hereafter named by its acronym ELIP) is the first accepted large igneous region in China.The current study tries to reconstruct the density structure of the crust in this region. Fo... The Emeishan large igneous province(hereafter named by its acronym ELIP) is the first accepted large igneous region in China.The current study tries to reconstruct the density structure of the crust in this region. For this purpose, we conducted the gravity survey along an 800-km-long profile, which stretched laterally along the latitude 27°N from Lijiang(Yunnan province) to Guiyang(Guizhou province). The fieldwork included 338 gravity measurements distributed from the inner zone to the outer zone of the mantle plume head.After a series of gravity reductions, we calculated the Bouguer gravity anomaly and then constructed the density model for ELIP by iterative forward modeling from an initial density model tightly constrained by wide-angle seismic reflection data. The topography of the Moho, here physically interpreted as a density discontinuity of ~0.4 g·cm^(–3), gradually rises from the inner zone(~50 km deep) to the outer zone(~40 km), describes a thicker crust in the inner zone than in any other segment of the profile and largely reproduces the shape of the Bouguer gravity anomaly curve. Both the Bouguer gravity and the density structure show significant differences with respect to the inner zone and the other two zones of ELIP according to the commonly accepted partition of the Emeishan area. A thicker and denser middle-lower crust seems to be the main feature of the western section of the profile, which is likely related to its mafic magmatic composition due to magmatic underplating of the Permian mantle plume. 展开更多
关键词 Bouguer GRAVITY seismic reflection data forward modeling CRUSTAL density structure EMEISHAN large IGNEOUS province South China
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Principle, Method of Object-Relation Hypermedia Data Model and Its Application in the Multimedia Spatial Data Management
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作者 Wang, Jianhua Guo, Jingjun +1 位作者 Zhu, Guorui Wu, Hehai 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2000年第1期53-60,共8页
In this paper, a new multimedia data model, namely object-relation hypermedia data model (O-RHDM) which is an advanced and effective multimedia data model is proposed and designed based on the extension and integratio... In this paper, a new multimedia data model, namely object-relation hypermedia data model (O-RHDM) which is an advanced and effective multimedia data model is proposed and designed based on the extension and integration of non first normal form (NF2) multimedia data model. Its principle, mathematical description, algebra operation, organization method and store model are also discussed. And its specific application example, in the multimedia spatial data management is given combining with the Hainan multimedia touring information system. 展开更多
关键词 data structures Information management Mathematical models
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Health diagnosis of ultrahigh arch dam performance using heterogeneous spatial panel vector model 被引量:1
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作者 Er-feng Zhao Xin Li Chong-shi Gu 《Water Science and Engineering》 EI CAS CSCD 2024年第2期177-186,共10页
Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in China.Safety control is essential to long-term operation of these dams.This study employed the flexibility coefficient and ... Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in China.Safety control is essential to long-term operation of these dams.This study employed the flexibility coefficient and plastic complementary energy norm to assess the structural safety of arch dams.A comprehensive analysis was conducted,focusing on differences among conventional methods in characterizing the structural behavior of the Xiaowan arch dam in China.Subsequently,the spatiotemporal characteristics of the measured performance of the Xiaowan dam were explored,including periodicity,convergence,and time-effect characteristics.These findings revealed the governing mechanism of main factors.Furthermore,a heterogeneous spatial panel vector model was developed,considering both common factors and specific factors affecting the safety and performance of arch dams.This model aims to comprehensively illustrate spatial heterogeneity between the entire structure and local regions,introducing a specific effect quantity to characterize local deformation differences.Ultimately,the proposed model was applied to the Xiaowan arch dam,accurately quantifying the spatiotemporal heterogeneity of dam performance.Additionally,the spatiotemporal distri-bution characteristics of environmental load effects on different parts of the dam were reasonably interpreted.Validation of the model prediction enhances its credibility,leading to the formulation of health diagnosis criteria for future long-term operation of the Xiaowan dam.The findings not only enhance the predictive ability and timely control of ultrahigh arch dams'performance but also provide a crucial basis for assessing the effectiveness of engineering treatment measures. 展开更多
关键词 Ultrahigh arch dam structural performance Deformation behavior Diagnosis criterion Panel data model
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A Multilevel Secure Relation-Hierarchical Data Model for a Secure DBMS
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作者 朱虹 冯玉才 《Journal of Modern Transportation》 2001年第1期8-16,共9页
A multilevel secure relation hierarchical data model for multilevel secure database is extended from the relation hierarchical data model in single level environment in this paper. Based on the model, an upper lowe... A multilevel secure relation hierarchical data model for multilevel secure database is extended from the relation hierarchical data model in single level environment in this paper. Based on the model, an upper lower layer relationalintegrity is presented after we analyze and eliminate the covert channels caused by the database integrity.Two SQL statements are extended to process polyinstantiation in the multilevel secure environment.The system based on the multilevel secure relation hierarchical data model is capable of integratively storing and manipulating complicated objects ( e.g. , multilevel spatial data) and conventional data ( e.g. , integer, real number and character string) in multilevel secure database. 展开更多
关键词 dataBASES data structure data models secure DBMS covert channels mandatory access control POLYINSTANTIATION hierarchical classification non hierarchical category security level integrity cluster index
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A Structural Equation Model (SEM) for Pharmacist Competencies in Improving Quality of Life of Cancer Patients: Effect of Missing Values on the SEM
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作者 Rieko Takehira Keiko Murakami +2 位作者 Sirou Katayama Kenji Nishizawa Shigeo Yamamura 《Pharmacology & Pharmacy》 2011年第3期226-232,共7页
Objective: With the goal of improving health-related quality of life (HRQOL) in cancer patients, we previously reported a structural equation model (SEM) of subjected QOL and qualifications of pharmacists, based on a ... Objective: With the goal of improving health-related quality of life (HRQOL) in cancer patients, we previously reported a structural equation model (SEM) of subjected QOL and qualifications of pharmacists, based on a series of questionnaires completed by patients and pharmacists. However, several patients and pharmacists were excluded from the previous study because it was not always possible to obtain all the data intended for collection. In order to reveal the effect of missing data on the SEM, we established SEMs of HRQOL and the competency of pharmacists, using correlation matrices derived by two different statistical methods for handling missing data. Method: Fifteen cancer patients hospitalized for cancer and were receiving opioid analgesics for pain control, and eight pharmacists were enrolled in this study. Each subject was asked four times weekly to answer questions presented in a questionnaire. SEMs were explored using two correlation matrices derived with pair-wise deletion (PD matrix) and list-wise deletion (LD matrix). The final models were statistically evaluated with certain goodness-of-fit criteria. Results: Data were intended to be collected four times weekly for each patient, but there were some missing values. The same SEMs for HRQOL were optimized using both the LD and PD matrices. Although the path diagrams of the SEMs were not identical in the “competency of pharmacists,” the two models suggested that a higher competency of a pharmacist lowered the “severity” of condition and increased the “comfort” of patients, resulting in an increase in the subjected QOL. Conclusion: In collecting data for clinical research, missing values are unavoidable. When the structure of the model was robust enough, the missing data had a minor effect on our SEM of QOL. In QOL research, the LD matrix as well as the PD matrix would be effective, provided the model is sufficiently robust. 展开更多
关键词 QOL Cancer Patients structural Equation model PHARMACISTS MISSING data
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