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Hydrothermal Synthesis and Characterization of a Novel Two-dimensional Framework Materials Constructed from Polyoxometalate and Coordination Groups: [H_2Mo_(5.5)V_(10.5)O_(40)(PO_4)][Cu(en)_2]_4·7H_2O
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作者 CUIXiao-bing ZHENGShou-tian +1 位作者 SUNYan-qiong YANGGuo-yu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第1期10-14,共5页
A novel compound [H_2Mo_ 5.5V_ 10.5O_ 40(PO_4)][Cu(en)_2]_4·7H_2O(1) was synthesized from V_2O_5, MoO_3, CuCl_2·2H_2O, en, H_3PO4 and H_2O in an aqueous solution via the hydrothermal method and characteri... A novel compound [H_2Mo_ 5.5V_ 10.5O_ 40(PO_4)][Cu(en)_2]_4·7H_2O(1) was synthesized from V_2O_5, MoO_3, CuCl_2·2H_2O, en, H_3PO4 and H_2O in an aqueous solution via the hydrothermal method and characterized by means of single-crystal X-ray diffraction, elemental analyses, IR, EPR spectra and thermal analyses. C_ 16H_ 80Cu_4Mo_ 5.5N_ 16O_ 51PV_ 10.5 crystallized in a triclinic system, the space group is P1 with M=2660.63, a= 1.283590(10) nm, b=1.289910(10) nm, c=1.387870(10) nm, V=1.80942(2) nm 3, Z=2, D_x=4.883 g/cm 3, F(000)=2599, μ=6.956 mm -1, (Δ/σ)=0.000, S=1.089. The crystal structure was solved by the direct methods with the final R=0.0752 and wR=0.1988 for 6311 observed reflections with I≥2σ(I). The X-ray crystallography reveals that compound 1 is a novel two-dimensional framework material constructed from the mixed Mo/V polyoxometalate and coordination groups. 展开更多
关键词 Hydrothermal synthesis two-dimensional framework Mixed Mo/V tetra-capped pseudo-Keggin structure POLYOXOMETaLaTE
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Hyperspectral remote sensing identification of marine oil spills and emulsions using feature bands and double-branch dual-attention mechanism network
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作者 Ning ZHANG Junfang YANG +2 位作者 Shanwei LIU Yi MA Jie ZHANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期728-743,共16页
The accurate identification of marine oil spills and their emulsions is of great significance for emergency response to oil spill pollution.The selection of characteristic bands with strong separability helps to reali... The accurate identification of marine oil spills and their emulsions is of great significance for emergency response to oil spill pollution.The selection of characteristic bands with strong separability helps to realize the rapid calculation of data on aircraft or in orbit,which will improve the timeliness of oil spill emergency monitoring.At the same time,the combination of spectral and spatial features can improve the accuracy of oil spill monitoring.Two ground-based experiments were designed to collect measured airborne hyperspectral data of crude oil and its emulsions,for which the multiscale superpixel level group clustering framework(MSGCF)was used to select spectral feature bands with strong separability.In addition,the double-branch dual-attention(DBDA)model was applied to identify crude oil and its emulsions.Compared with the recognition results based on original hyperspectral images,using the feature bands determined by MSGCF improved the recognition accuracy,and greatly shortened the running time.Moreover,the characteristic bands for quantifying the volume concentration of water-in-oil emulsions were determined,and a quantitative inversion model was constructed and applied to the AVIRIS image of the deepwater horizon oil spill event in 2010.This study verified the effectiveness of feature bands in identifying oil spill pollution types and quantifying concentration,laying foundation for rapid identification and quantification of marine oil spills and their emulsions on aircraft or in orbit. 展开更多
关键词 hyperspectral image spectral analysis dimensionality reduction multiscale superpixel level group clustering framework(MSGCF) double-branch dual-attention(DBDa)
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Research of a New Multi-dimensional Dataset Search Framework on Unstructured P2P
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作者 DENG Hui-min ZENG Bi-qing XIA Xu 《通讯和计算机(中英文版)》 2007年第1期1-7,共7页
关键词 复合型数据 数据挖掘 P2P系统 数据询问
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Exploring the Three-dimensional Framework of Knowledge Service in the field of Library and Information Science(LIS)
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作者 WANG Yuefen ZHANG Beibei WU Tingting 《Chinese Journal of Library and Information Science》 2010年第2期31-47,共17页
The evolution of the society and economy has stimulated the development of Knowledge Service(KS), making it an indispensable solution to address future challenges facing libraries and information institutions. However... The evolution of the society and economy has stimulated the development of Knowledge Service(KS), making it an indispensable solution to address future challenges facing libraries and information institutions. However at present, academic research on knowledge service is falling short and its definition is far from clear and complete. As such,this article proposes the Three-dimensional Framework Knowledge Service(TdFKS) for libraries and information institutions based on the knowledge value chain model. By making reliability analysis and mean value analysis of a questionnaire survey result, the article clarifies the structure of the three-dimensional framework and verifies the rationality of the TdFKS. 展开更多
关键词 Libraries and information institutions Knowledge service Three-dimensional framework Reliability analysis Mean value analysis
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Crystallographically vacancy‐induced MOF nanosheet as rational single‐atom support for accelerating CO_(2) electroreduction to CO
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作者 Jin Hyuk Cho Joonhee Ma +12 位作者 Chaehyeon Lee Jin Wook Lim Youngho Kim Ho Yeon Jang Jaehyun Kim Myung‐gi Seo Youngheon Choi Youn Jeong Jang Sang Hyun Ahn Ho Won Jang Seoin Back Jong‐Lam Lee Soo Young Kim 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期49-62,共14页
To attain a circular carbon economy and resolve CO_(2) electroreduction technology obstacles,single‐atom catalysts(SACs)have emerged as a logical option for electrocatalysis because of their extraordinary catalytic a... To attain a circular carbon economy and resolve CO_(2) electroreduction technology obstacles,single‐atom catalysts(SACs)have emerged as a logical option for electrocatalysis because of their extraordinary catalytic activity.Among SACs,metal–organic frameworks(MOFs)have been recognized as promising support materials because of their exceptional ability to prevent metal aggregation.This study shows that atomically dispersed Ni single atoms on a precisely engineered MOF nanosheet display a high Faradaic efficiency of approximately 100% for CO formation in H‐cell and three‐compartment microfluidic flow‐cell reactors and an excellent turnover frequency of 23,699 h^(−1),validating their intrinsic catalytic potential.These results suggest that crystallographic variations affect the abundant vacancy sites on the MOF nanosheets,which are linked to the evaporation of Zn‐containing organic linkers during pyrolysis.Furthermore,using X‐ray absorption spectroscopy and density functional theory calculations,a comprehensive investigation of the unsaturated atomic coordination environments and the underlying mechanism involving CO^(*) preadsorbed sites as initial states was possible and provided valuable insights. 展开更多
关键词 2‐dimensional material carbon dioxide reduction metal-organic frameworks single‐atom catalysts vacancy sites
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A UML profile for framework modeling 被引量:1
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作者 徐小良 汪乐宇 周泓 《Journal of Zhejiang University Science》 CSCD 2004年第1期92-98,共7页
The current standard Unified Modeling Language(UML) could not model framework flexibility and extendibility adequately due to lack of appropriate constructs to distinguish framework hot-spots from kernel elements. A n... The current standard Unified Modeling Language(UML) could not model framework flexibility and extendibility adequately due to lack of appropriate constructs to distinguish framework hot-spots from kernel elements. A new UML profile that may customize UML for framework modeling was presented using the extension mechanisms of UML, providing a group of UML extensions to meet the needs of framework modeling. In this profile, the extended class diagrams and sequence diagrams were defined to straightforwardly identify the hot-spots and describe their instantiation restrictions. A transformation model based on design patterns was also put forward, such that the profile based framework design diagrams could be automatically mapped to the corresponding implementation diagrams. It was proved that the presented profile makes framework modeling more straightforwardly and therefore easier to understand and instantiate. 展开更多
关键词 Object oriented frameworks Unified Modeling Language(UML) UML profile Hot spots Design patterns
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Multi-objective Optimization Design of Wing Structure with the Model Management Framework 被引量:3
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作者 安伟刚 李为吉 苟仲秋 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2006年第1期31-35,共5页
Evolutionary algorithm is time-consuming because of the large number of evolutions and much times of finite element analysis, when it is used to optimize the wing structure of a certain high altitude long endurance un... Evolutionary algorithm is time-consuming because of the large number of evolutions and much times of finite element analysis, when it is used to optimize the wing structure of a certain high altitude long endurance unmanned aviation vehicle(UAV). In order to improve efficiency it is proposed to construct a model management framework to perform the multi-objective optimization design of wing structure. The sufficient accurate approximation models of objective and constraint functions in the wing structure optimization model are built when using the model management framework, therefore in the evolutionary algorithm a number of finite element analyses can he avoided and the satisfactory multi-objective optimization results of the wing structure of the high altitude long endurance UAV are obtained. 展开更多
关键词 wing structure UaV multi-objective opti-mization model management framework SM- MOPSO
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A Design Method of Business Application Framework Based on Software Patterns
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作者 He Ke\|qing 1, Yang Chun wen 1, Ying Shi 2 1. School of Computer Science, Wuhan University, Wuhan 430072, China 2. State Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期204-208,共5页
This paper discusses design and implementation method of Business Application Framework based on software patterns, and then presents MVC pattern of architecture and the method of dynamical update promulgation for Bus... This paper discusses design and implementation method of Business Application Framework based on software patterns, and then presents MVC pattern of architecture and the method of dynamical update promulgation for Business Application Framework. We discuss adaptation of Abstract Factory for the kernel functionality of Business Application Framework, such as data creation, manipulation, composition, etc. It also presents class model and its class structure of Abstract Factory pattern. Finally, we briefly discuss the update, modification, and reconstruction method of Business Application Framework. 展开更多
关键词 object oriented MVC pattern abstract Factory pattern software framework UML role model
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An Analysis Method of Business Application Framework
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作者 He Ke\|qing 1,Fan Hui hua 1,Ying Shi 2 1.Department of Computer Science, Wuhan University, Wuhan 430072, China 2.State Key Laboratory of Software Engineering, Wuhan University, Wuhan 430072, China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期218-223,共6页
We discuss the evolution of object oriented software development process based on software pattern. For developing mature software framework and component, we advocate to elicit and incorporate software patterns for ... We discuss the evolution of object oriented software development process based on software pattern. For developing mature software framework and component, we advocate to elicit and incorporate software patterns for ensuing quality and reusability of software frameworks. On the analysis base of requirement specification for business application domain, we present analysis method and basic role model of software framework. We also elicit analysis pattern of framework architecture, and design basic role classes and their structure. 展开更多
关键词 object oriented software framework analysis pattern of architecture COMPONENT role model
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Development of the Data Processing and Analysis System Framework for ICF Experiments
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作者 杨冬 虞孝麒 张弛 《Plasma Science and Technology》 SCIE EI CAS CSCD 2005年第3期2872-2874,共3页
An idea is presented about the development of a data processing and analysis system for ICF experiments, which is based on an object oriented framework. The design and preliminary implementation of the data processing... An idea is presented about the development of a data processing and analysis system for ICF experiments, which is based on an object oriented framework. The design and preliminary implementation of the data processing and analysis framework based on the ROOT system have been completed. Software for unfolding soft X-ray spectra has been developed to test the functions of this framework. 展开更多
关键词 initial confinement fusion data processing and analysis object oriented framework ROOT soft X-ray spectra
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Optical encryption of multiple three-dimensional objects based on multiple interferences and single-pixel digital holography 被引量:2
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作者 Ying Wang Qi Liu +1 位作者 Jun Wang Qiong-Hua Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第3期253-259,共7页
We present an optical encryption method of multiple three-dimensional objects based on multiple interferences and single-pixel digital holography. By modifying the Mach-Zehnder interferometer, the interference of the ... We present an optical encryption method of multiple three-dimensional objects based on multiple interferences and single-pixel digital holography. By modifying the Mach-Zehnder interferometer, the interference of the multiple objects beams and the one reference beam is used to simultaneously encrypt multiple objects into a ciphertext. During decryption, each three-dimensional object can be decrypted independently without having to decrypt other objects. Since the single- pixel digital holography based on compressive sensing theory is introduced, the encrypted data of this method is effectively reduced. In addition, recording fewer encrypted data can greatly reduce the bandwidth of network transmission. Moreover, the compressive sensing essentially serves as a secret key that makes an intruder attack invalid, which means that the system is more secure than the conventional encryption method. Simulation results demonstrate the feasibility of the proposed method and show that the system has good security performance. 展开更多
关键词 multiple three-dimensional objects encryption single-pixel digital holography phase-shifting in- terference compressive sensing
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Analysis of Object Depth Effects on Accuracy of Dimensional Shape in X and Y Directions Using Single Non-metric Image
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作者 Tarek M.A. ZHU Qing 《Geo-Spatial Information Science》 2007年第4期269-275,共7页
In general, to reconstruct the accurate shape of buildings, we need at least one stereomodel (two photographs) for each building. In most cases, however, only a single non-metric photograph is available, which is us... In general, to reconstruct the accurate shape of buildings, we need at least one stereomodel (two photographs) for each building. In most cases, however, only a single non-metric photograph is available, which is usually obtained either by an amateur, such as a tourist, or from a newspaper or a post card. To evaluate the validity of 3D reconstruction from a single non-metric image, this study analyzes the effects of object depth on the accuracy of dimensional shape in X and Y directions using a single non-metric image by means of simulation technique, as this was considered to be, in most cases, a main source of data acquisition in recording and documenting buildings. 展开更多
关键词 SINGLE non-metric image reconstruction object depth aCCURaCY dimensional shape
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Customer Churn Prediction Framework of Inclusive Finance Based on Blockchain Smart Contract
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作者 Fang Yu Wenbin Bi +2 位作者 Ning Cao Hongjun Li Russell Higgs 《Computer Systems Science & Engineering》 SCIE EI 2023年第10期1-17,共17页
In view of the fact that the prediction effect of influential financial customer churn in the Internet of Things environment is difficult to achieve the expectation,at the smart contract level of the blockchain,a cust... In view of the fact that the prediction effect of influential financial customer churn in the Internet of Things environment is difficult to achieve the expectation,at the smart contract level of the blockchain,a customer churn prediction framework based on situational awareness and integrating customer attributes,the impact of project hotspots on customer interests,and customer satisfaction with the project has been built.This framework introduces the background factors in the financial customer environment,and further discusses the relationship between customers,the background of customers and the characteristics of pre-lost customers.The improved Singular Value Decomposition(SVD)algorithm and the time decay function are used to optimize the search and analysis of the characteristics of pre-lost customers,and the key index combination is screened to obtain the data of potential lost customers.The framework will change with time according to the customer’s interest,adding the time factor to the customer churn prediction,and improving the dimensionality reduction and prediction generalization ability in feature selection.Logistic regression,naive Bayes and decision tree are used to establish a prediction model in the experiment,and it is compared with the financial customer churn prediction framework under situational awareness.The prediction results of the framework are evaluated from four aspects:accuracy,accuracy,recall rate and F-measure.The experimental results show that the context-aware customer churn prediction framework can be effectively applied to predict customer churn trends,so as to obtain potential customer data with high churn probability,and then these data can be transmitted to the company’s customer service department in time,so as to improve customer churn rate and customer loyalty through accurate service. 展开更多
关键词 Contextual awareness customer churn prediction framework dimensionality reduction generalization ability
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A New Heteropolyoxotungstate with a Three-dimensional All-inorganic Framework [(C_2H_4N_2)_4(P_4Co_3W_4O_(28)H_6)(H_2C_2O_4)]_n
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作者 孙军 孙宇 +1 位作者 陈亚光 孟凡霞 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第6期962-966,共5页
A new heteropolyoxotungstate [(C2H4N2)4(P4Co3W4O28H6)(H2C2O4)]n with a three-dimensional framework was hydrothermally synthesized.The compound crystallizes in a tetragonal system,space group I41/a with a = 17.1... A new heteropolyoxotungstate [(C2H4N2)4(P4Co3W4O28H6)(H2C2O4)]n with a three-dimensional framework was hydrothermally synthesized.The compound crystallizes in a tetragonal system,space group I41/a with a = 17.1006(17),b = 17.1006(7),c = 10.7525(5),V = 3144.2(2)3,Z = 4,Dc = 3.795 g·cm-3,F(000) = 3300,MoKα(λ = 0.71073 ),μ = 16.460 mm-1,the final R = 0.0335 and wR = 0.0776.In the heteropolyoxotungstate,tungsten-oxygen octahedra are linked by sharing two cis-vertexes into an infinite helical chain extending along the c axis.Cobalt atoms in the octahedral geometry act as the linkers of these chains,forming a three-dimensional framework.The cobalt and phosphorus atoms in the tetrahedral geometry play a role in stabilizing the three-dimensional framework.Ethylenediamine molecules are polymerized into organic chains which locate in the interspaces of the framework in the way of interwinding with the W-O chains. 展开更多
关键词 hydrothermal synthesis POLYOXOTUNGSTaTE three-dimensional framework W-O chains organic ammine
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Variability-Based Models for Testability Analysis of Frameworks
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作者 Divya Ranjan Anil Kumar Tripathi 《Journal of Software Engineering and Applications》 2010年第5期455-459,共5页
Frameworks are developed to capture the recurring design practices in terms of skeletons of software subsystems/ systems. They are designed ‘abstract’ and ‘incomplete’ and are designed with predefined points of va... Frameworks are developed to capture the recurring design practices in terms of skeletons of software subsystems/ systems. They are designed ‘abstract’ and ‘incomplete’ and are designed with predefined points of variability, known as hot spots, to be customized later at the time of framework reuse. Frameworks are reusable entities thus demand stricter and rigorous testing in comparison to one-time use application. It would be advisable to guaranty the production of high quality frameworks without incurring heavy costs for their rigorous testing. The overall cost of framework development may be reduced by designing frameworks with high testability. This paper aims at discussing various metric models for testability analysis of frameworks in an attempt to having quantitative data on testability to be used to plan and monitor framework testing activities so that the framework testing effort and hence the overall framework development effort may be brought down. The models considered herein particularly consider that frameworks are inherently abstract and variable in nature. 展开更多
关键词 OBJECT-ORIENTED frameworks VaRIaBILITY Customizability and TESTaBILITY
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Open-Access Framework for Efficient Object-Oriented Development of Video Analysis Software
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作者 Dimitris K. Iakovidis Dimitris Diamantis 《Journal of Software Engineering and Applications》 2014年第8期730-743,共14页
The increasing use of digital video everyday in a multitude of electronic devices, including mobile phones, tablets and laptops, poses the need for quick development of cross-platform video software. However current a... The increasing use of digital video everyday in a multitude of electronic devices, including mobile phones, tablets and laptops, poses the need for quick development of cross-platform video software. However current approaches to this direction usually require a long learning curve, and their development lacks standardization. This results in software components that are difficult to reuse, and hard to maintain or extend. In order to overcome such issues, we propose a novel object-oriented framework for efficient development of software systems for video analysis. It consists of a set of four abstract components, suitable for the implementation of independent plug-in modules for video acquisition, preprocessing, analysis and output handling. The extensibility of each module can be facilitated by sub-modules specifying additional functionalities. This architecture enables quick responses to changes and re-configurability;thus conforming to the requirements of agile software development practices. Considering the need for platform independency, the proposed Java Video Analysis (JVA) framework is implemented in Java. It is publicly available through the web as open-access software, supported by a growing collection of implemented modules. Its efficiency is empirically validated for the development of a representative video analysis system. 展开更多
关键词 OBJECT-ORIENTED framework EFFICIENT SofTWaRE Development VIDEO analysis Java
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Testability Estimation of Framework Based Applications
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作者 Noopur Goel Manjari Gupta 《Journal of Software Engineering and Applications》 2012年第11期841-849,共9页
Quality of software systems is highly demanded in today’s scenario. Highly testable system enhances the reliability also. More than 50% of test effort-time and cost are used to produce a highly testable system. Thus,... Quality of software systems is highly demanded in today’s scenario. Highly testable system enhances the reliability also. More than 50% of test effort-time and cost are used to produce a highly testable system. Thus, design-for-testability is needed to reduce the test effort. In order to enhance the quality, productivity and reduced cost of the software organizations are promoting to produce the reuse-oriented products. Incorporating reuse technology in both aspects-software development process and test process may payoff many folds. Keeping this view, our study focus the testability of the object-oriented framework based software systems and identify that flexibility at the variable points of the object-oriented framework, chosen for framework instantiation, greatly affects the testability of object-oriented framework based software at each level of testing. In the current paper, we propose a testability model considering the flexible aspect of the variable point to estimate testability in the early phase, requirement analysis phase, of development process of the framework based software. The proposed model helps to improve the testability of the software before the implementation starts thus reducing the overall development cost. 展开更多
关键词 Reuse-Technology Variation-Points OBJECT-ORIENTED framework BaSED Software Basic TEST Cases framework Interface CLaSSES Other application CLaSSES
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CAPPFramework工艺信息面向对象建模体系 被引量:6
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作者 张振明 桓永兴 +1 位作者 许建新 黄乃康 《机械科学与技术》 CSCD 北大核心 2000年第6期1019-1021,共3页
CAPP应用框架与开发平台 (CAPPFram eworks)是一个以面向对象 CAPP知识库系统为核心的通用交互式 CAPP应用支撑软件。本文应用面向对象的概念与原理 ,建立 CAPPFrameworks面向对象建模体系 (CAPPFram eworks- OOM) ,其基本模型包括 :CAP... CAPP应用框架与开发平台 (CAPPFram eworks)是一个以面向对象 CAPP知识库系统为核心的通用交互式 CAPP应用支撑软件。本文应用面向对象的概念与原理 ,建立 CAPPFrameworks面向对象建模体系 (CAPPFram eworks- OOM) ,其基本模型包括 :CAPP对象类树 (Class Tree,CT)、CAPP对象类表示及 CAPP对象关系图 (Object Relation Graph,ORG)。该建模体系已成为 展开更多
关键词 CaPPframework 面向对象 信息建模
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软件复用与Framework框架技术 被引量:9
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作者 李秀芳 张福增 贾世祥 《科学技术与工程》 2006年第1期80-83,共4页
讲述了软件复用的基本概念和关键技术因素,分析了框架技术的基本概念以及常见的框架系统,并将框架同构件、设计模式进行了比较,最后给出了基于面向对象框架的软件开发过程模型。
关键词 软件复用 框架 构件 设计模式 面向对象
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EFFECT OF TIME AND ENVIRONMENT ON THE DIMENSION PRECISION AND MASS OF LOM PROTOTYPES
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作者 张连洪 李华友 《Transactions of Tianjin University》 EI CAS 2001年第3期214-216,共3页
The effect of time and environment on the dimension precision and mass of LOM prototypes was experimentally investigated.It is to identify the stability of the dimension of LOM prototypes after forming.The results sho... The effect of time and environment on the dimension precision and mass of LOM prototypes was experimentally investigated.It is to identify the stability of the dimension of LOM prototypes after forming.The results show that the dimension and the mass tendency to grow,which is mainly caused by elastic recovery and moisture absorption and is characterized principally by the growth of Z dimension.Self restraint can be a significant factor to influence Z growth of LOM prototypes. 展开更多
关键词 laminated object manufacturing (LOM) time effect dimension stability rapid prototyping
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