Object-oriented Data Model Research Articles

EDMS: an engineering data management system for design supporting environments

As the popularity of design supporting environments and the large volume of data created during the design process have increased, how to effectively manage the engineering data has become an interesting as well as important research topic. In this paper, we present an object–oriented engineering data management system (EDMS) that not only has the advantages of an object–oriented data model, such as flexible incorporation of application–specific rules within each object, but also has the advantages of (1) being adaptable to existing design tools, and (2) supporting both top–down and bottom–up design paradigms. The first advantage saves re–investment in new design tools, while the second promotes the reusability of design data. In addition to the detailed description of the proposed data model, a computer system design example will be presented to illustrate the application of the EDMS. The implementation mechanisms arc also explored.

A new geospatial overlay method for the analysis and visualization of spatial change patterns using object-oriented data modeling concepts

Traditional geographic information system (GIS)-overlay routines usually build on relatively simple data models. Topology is – if at all – calculated on the fly for very specific tasks only. If, for example, a change comparison is conducted between two or more polygon layers, the result leads mostly to a complete and also very complex from–to class intersection. A lot of additional processing steps need to be performed to arrive at aggregated and meaningful results. To overcome this problem a new, automated geospatial overlay method in a topologically enabled (multi-scale) framework is presented. The implementation works with polygon and raster layers and uses a multi-scale vector/raster data model developed in the object-based image analysis software eCognition (Trimble Geospatial Imaging, Munich, Germany). Advantages are the use of the software inherent topological relationships in an object-by-object comparison, addressing some of the basic concepts of object-oriented data modeling such as classification, generalization, and aggregation. Results can easily be aggregated to a change-detection layer; change dependencies and the definition of different change classes are interactively possible through the use of a class hierarchy and its inheritance (parent–child class relationships). Implementation is exemplarily shown for a change comparison of CORINE Land Cover data sets. The result is a flexible and transferable solution which is – if parameterized once – fully automated.

BIM-Enabled Conceptual Modelling and Representation of Building Circulation

This paper describes how a building information modelling (BIM)-based approach for building circulation enables us to change the process of building design in terms of its computational representation and processes, focusing on the conceptual modelling and representation of circulation within buildings. BIM has been designed for use by several BIM authoring tools, in particular with the widely known interoperable industry foundation classes (IFCs), which follow an object-oriented data modelling methodology. Advances in BIM authoring tools, using space objects and their relations defined in an IFC's schema, have made it possible to model, visualize and analyse circulation within buildings prior to their construction. Agent-based circulation has long been an interdisciplinary topic of research across several areas, including design computing, computer science, architectural morphology, human behaviour and environmental psychology. Such conventional approaches to building circulation are centred on navigational knowledge about built environments, and represent specific circulation paths and regulations. This paper, however, places emphasis on the use of ‘space objects’ in BIM-enabled design processes rather than on circulation agents, the latter of which are not defined in the IFCs' schemas. By introducing and reviewing some associated research and projects, this paper also surveys how such a circulation representation is applicable to the analysis of building circulation-related rules.

Status of the development of a fully integrated code system for the simulation of high temperature reactor cores

The HTR code package (HCP) is a new code system, which couples a variety of stand-alone codes for the simulation of different aspects of HTR. HCP will allow the steady-state and transient operating conditions of a 3D reactor core to be simulated including new features such as spatially resolved fission product release calculations or production and transport of graphite dust. For this code the latest programming techniques and standards are applied. As a first step an object-oriented data model was developed which features a high level of readability because it is based on problem-specific data types like Nuclide, Reaction, ReactionHandler, CrossSectionSet, etc. Those classes help to encapsulate and therefore hide specific implementations, which are not relevant with respect to physics. HCP will make use of one consistent data library for which an automatic generation tool was developed. The new data library consists of decay information, cross sections, fission yields, scattering matrices etc. for all available nuclides (e.g. ENDF/B-VII.1). The data can be stored in different formats such as binary, ASCII or XML. The new burn up code TNT (Topological Nuclide Transmutation) applies graph theory to represent nuclide chains and to minimize the calculation effort when solving the burn up equations. New features are the use of energy-dependent fission yields or the calculation of thermal power for decay, fission and capture reactions. With STACY (source term analysis code system) the fission product release for steady state as well as accident scenarios can be simulated for each fuel batch. For a full-core release calculation several thousand fuel elements are tracked while passing through the core. This models the stochastic behavior of a pebble bed in a realistic manner. In this paper we report on the current status of the HCP and present first results, which prove the applicability of the selected approach.

Modelling Information Retrieval in an Object-Oriented Database Environment

From the 1994 CAIS Conference: The Information Industry in Transition McGill University, Montreal, Quebec. May 25 - 27, 1994.Bibliographic or full text information retrieval (IR) applications have been implemented either as special purpose programs or as systems based on database technology. The relational model has been used with some success but most work has used separate IR specific models. The object-oriented data model offers many advantages by incorporating documents as complex objects. Basic concepts such as objects, class hierarchy, inheritance, aggregation, collections and methods are applied to the IR situation. Various approaches to query processing are introduced. To illustrate these concepts a partial implementation in object-Pascal is presented. Problems of standardization and formalization are discussed.

AN AUTOMATIC METHOD FOR THE DESIGN OF MULTIDIMENSIONAL SCHEMAS FROM OBJECT ORIENTED DATABASES

A data warehouse (DW) is a large data repository system designed for decision-making purposes. Its design relies on a specific model called multidimensional. This multidimensional model supports analyses of huge volumes of data that trace the enterprise's activities over time. Several design methods were proposed to build multidimensional schemas from either the relational data model or the entity-relationship data model. Almost all proposals that treated the object-oriented data model assume the presence of the data source UML class-diagram. However, in practice, either such a diagram does not exist or is obsolete due to multiple changes/evolutions of the information system. Furthermore, these few proposals require an intense manual intervention of the designer, which requires a high expertise both in the DW domain and in the object database domain. To overcome these disadvantages, this work proposes an automatic DW schema design method starting from an object database (schema and its instances). This method applies a set of extraction rules to identify multidimensional concepts and to generate star schemas. It is defined for the standard ODMG model and, thus, can be adapted with slight changes for other object database models. In addition, its extraction rules have the merit of being independent of the domain semantics. Furthermore, they automatically generate schemas classified according to their analytical potential; this classification helps the DW designer in selecting the most relevant schemas among the generated ones. Finally, being automatic, our method is supported by a toolset that also prepares for the automatic generation of the Extract Transform and Load procedures used to load the DW.

Data-modeling and implementation for massive construction project data based on manageable entity-oriented object

For the requirements of building Project Information Portal(PIP) data center based on a unified data model,a manageable entity object-oriented data model was proposed.The project data were treated as a series of managerial entity based on management workflows which were decomposed according to the whole life cycle.The conceptual layer data model was designed.The project data could be naturally represented and recorded by using this model.The data organization method was presented based on MongoDB(document-oriented database technology).The cluster storage architecture for PIP was also addressed.The experiments show that it has efficient performance in data writing and querying.It also has high availability and storage capacity scalability.

The Design of the Computer Aided Management System for Railway Electrification Engineering Logistics

The logistics of railway electrification engineering, because of its unique industrial characteristics and intrinsic characteristics, can't be directly applied to the existing departments, industries, and the management information systems of other countries at present. In this paper, the logistics system of railway electrification engineering is analyzed based on object oriented analysis and in combination with the supply chain management information system and the author thinks that the key to analyzing the logistics information management system design of railway electrification engineering lies in the expression to the railway electrification engineering transportation supply chain management logic structure, and finally a computer aided decision system (CPFR model) based on the railway electrification engineering transportation supply chain distribution is established using data mining technology and object-oriented data model.

A Unified 3D Spatial Data Model for Surface and Subsurface Spatial Objects

Three Dimensional (3D) spatial modelling is an abstract representation of reality using mathematically proven relationships defined as points, lines, polygons and solids to represent man-made and natural features above, on and below the surface of the earth. 3D topology is the interrelationships existing between these objects to enable visualization, query and analysis. 3D mod-elling of subsurface objects and their integration with the surface and above surface objects currently lags behind despite efforts of researchers and the attempt at viewing above, surface and subsurface man-made objects for earth realism. Level of Details (LoD) for spatial objects has been extensively studied. However, these have not been extended to man-made features below the surface. LoD maps for surface and subsurface integration exist for most city centres but the 3D component is lacking and this does not enhance the Level of Realism (LoR) in most city centres. Knowledge about the surface and subsurface 3D objects for city centres, mining and 3D cadastre will create awareness among stakeholders for effective planning of a city or mine. This paper provides a discussion for 3D surface and subsurface integration. Various 3D spatial data models currently in existence for the integration of surface and subsurface models are discussed and a geometric, topological 3D object oriented model is sug-gested. A UML diagram for the top hierarchy class is presented and a conceptual and logical model for surface and subsurface integration is also discussed. A simulation of the above, on and below 3D spatial models for man-made constructions at differ-ent LoDs is presented. A simulation of this with regards to mining and cadastre is also presented. The model presented can be adopted in realising 3D GIS for mining and 3D cadastre can be realised in Ghana. Further work is geared towards 3D spatial analysis for such an integrated model.

Content Repository in Object Oriented data model

The need for creating content repository stores for e-learning systems grows as the number of available materials increases. Moreover, along with the number of courses, the problem of describing them in a unified form appears. While there are standards used for strict classification of elearning content, the store model still seems to be based on preservative relational databases approach.In this paper we introduce an idea to represent the e-learning content management information in the well organized object-oriented form based on a prospective object-oriented database.

Content Repository in Object Oriented data model

The need for creating content repository stores for e-learning systems grows as the number of available materials increases. Moreover, along with the number of courses, the problem of describing them in a unified form appears. While there are standards used for strict classification of elearning content, the store model still seems to be based on preservative relational databases approach.In this paper we introduce an idea to represent the e-learning content management information in the well organized object-oriented form based on a prospective object-oriented database.

Study of the Spatio-Temporal Data Model in Sea Battlefield

An effective analysis of the battlefield situation and spatio-temporal data model in a sea battlefield has great significance for the commander to perceive the battlefield situation and to make the right decisions. Based on the existing spatio-temporal data model, the present paper gives a comprehensive analysis of the characteristics of sea battlefield data, and chooses the object-oriented spatio-temporal data model to modify it; at the same time this paper introduces sea battlefield space-time algebra system to define various data types formally, which lays the foundation for the establishment of the sea battlefield spatio-temporal data model.

Translation from entities-relationship model to object-oriented data model.

Translation from entities-relationship model to object-oriented data model.

A method for translation from relational data model to object-oriented data model.

A method for translation from relational data model to object-oriented data model.

Representation and Reasoning of Fuzzy Object-Oriented Data Model with Description Logic

通过分析描述逻辑与面向对象数据模型之间的关系,研究了基于描述逻辑的模糊面向对象数据(fuzzy object-oriented data,简称FOOD)模型的表示与推理.首先,进一步研究了FOOD 模型,提出了FOOD 模型的形式化定义和语义定义,以便更好地在FOOD模型与模糊描述逻辑之间建立对应关系;然后,针对FOOD模型的特点和推理需求,介绍了模糊描述逻辑f-ALCIQ.在此基础上,研究了基于f-ALCIQ 的FOOD 模型的表示与推理,包括:实现了从 FOOD 模型到f-ALCIQ 知识库在结构层和实例层上的转化,即实现了从FOOD 模型到f-ALCIQ TBox 的转化,以及从FOOD 模型相应的数据库实例到f-ALCIQ ABox 的转化;进而,基于转化得到的f-ALCIQ 知识库,研究了如何利用 f-ALCIQ 的推理机制对FOOD 模型的推理问题(一致性、包含性和冗余性等)进行推理;最后,设计并实现了基于f-ALCIQ 的模糊描述逻辑推理机(FRsQ 推理机),实现了对FOOD 模型和f-ALCIQ 模糊概念知识的自动推理.

Designing a New Assertion Constraints Model for Mobile Databases

In this paper a new assertion constraint model is proposed and implemented. The model is designed to enforce and maintain the integrity constraints in mobile database and object data model environments. It has an object assertion model for integrity constraints which it is used to create classes and collect attributes and their constraints that are derived from multiple composition or inheritance hierarchies. Also it has a compile-time model which keeps the derivation path along with the attributesâ?? relationships. Furthermore, the run-time model enforces integrity constraints, enforcing the logical integrity constraints during the run-time. And a new technique is designed to check the object metadata to detect the object violation before it occurs. However, the model is implemented and tested over set of definitions that check attribute values validity and objects for object-oriented and mobile databases.

Searching Web Data: An Entity Retrieval and High-Performance Indexing Model

More and more (semi) structured information is becoming available on the Web in the form of documents embedding metadata (e.g., RDF, RDFa, Microformats and others). There are already hundreds of millions of such documents accessible and their number is growing rapidly. This calls for large scale systems providing effective means of searching and retrieving this semi-structured information with the ultimate goal of making it exploitable by humans and machines alike. This article examines the shift from the traditional web document model to a web data object (entity) model and studies the challenges faced in implementing a scalable and high performance system for searching semi-structured data objects over a large heterogeneous and decentralised infrastructure.Towards this goal, we define an entity retrieval model, develop novel methodologies for supporting this model and show how to achieve a high-performance entity retrieval system. We introduce an indexing methodology for semi-structured data which offers a good compromise between query expressiveness, query processing and index maintenance compared to other approaches. We address high-performance by optimisation of the index data structure using appropriate compression techniques. Finally, we demonstrate that the resulting system can index billions of data objects and provides keyword-based as well as more advanced search interfaces for retrieving relevant data objects in sub-second time. This work has been part of the Sindice search engine project at the Digital Enterprise Research Institute (DERI), NUI Galway. The Sindice system currently maintains more than 120 million pages downloaded from the Web and is being used actively by many researchers within and outside of DERI.

Computer Data Structure for Geological Entities Modelling Based on OO-Solid Model

In the long evolution of the earth formation often form a complex geological structure, modeling for these complex geological entities (such as thinning-out, bifurcation, reverse, etc.) still require in-depth 3D modeling study. Because of discontinuity, complexity and uncertainty of distribution of 3D geo-objects, some models only are suitable for regular, continuous and relatively simple spatial objects, and some are suitable for discontinue, complex and uncertain geo-objects, but some improvements on these models, such as, updating of model, maintenance of topological and seamless integration between models, are still to be made. OO-Solid model, put forward by writer in 2002, is an object- oriented topological model based on sections. The OO-Solid Model is an object-oriented 3D topologic data model based on component for geology modeling with fully considering the topological relations between geological objects and its geometric primitives, Comparatively, it accords with the actual requirements of three-dimensional geological modeling . The key issue of 3D geology modeling is the 3D data model. Some data models are suitable for discontinue, complex and uncertain geo-objects, but the OO-Solid model is an object-oriented 3D topologic data model based on component for geology modeling with fully considering the topological relations between geological objects and its geometric primitives. OO-Solid model and data structure are designed. At last, 3D complex geological entities modeling based on OO-Solid are studied in this paper. These study is important and one of the core techniques for the 3DGM.

Generating database migrations for evolving web applications

WebDSL is a domain-specific language for the implementation of dynamic web applications with a rich data model. It provides developers with object-oriented data modeling concepts but abstracts over implementation details for persisting application data in relational databases. When the underlying data model of an application evolves, persisted application data has to be migrated. While implementing migration at the database level breaks the abstractions provided by WebDSL, an implementation at the data model level requires to intermingle migration with application code. In this paper, we present a domain-specific language for the coupled evolution of data models and application data. It allows to specify data model evolution as a separate concern at the data model level and can be compiled to migration code at the database level. Its linguistic integration with WebDSL enables static checks for evolution validity and correctness.

P1-43 Bridging electrical data entry sheet and statistical software by standard data model

IntroductionInteroperability of collected dataset has been distress for researchers. Introduction of database management software made some improvements, however, still we need many of craftworks to convert and clean up original...