• Title/Summary/Keyword: Data Access Object

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A Streaming XML Parser Supporting Adaptive Parallel Search (적응적 병렬 검색을 지원하는 스트리밍 XML 파서)

  • Lee, Kyu-Hee;Han, Sang-Soo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.8
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    • pp.1851-1856
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    • 2013
  • An XML is widely used for web services, such as SOAP(Simple Object Access Protocol) and REST (Representational State Transfer), and also de facto standard for representing data. Since the XML parser using DOM(Document Object Model) requires a preprocessing task creating a DOM-tree, and then storing it into memory, embedded systems with limited resources typically employ a streaming XML parser without preprocessing. In this paper, we propose a new architecture for the streaming XML parser using an APSearch(Adaptive Parallel Search) on FPGA(Field Programmable Gate Array). Compared to other approaches, the proposed APSearch parser dramatically reduces overhead on the software side and achieves about 2.55 and 2.96 times improvement in the time needed for an XML parsing. Therefore, our APSearch parser is suitable for systems to speed up XML parsing.

Object-Size and Call-Site Tracing based Shared Memory Allocator for False Sharing Reduction in DSM Systems (분산 공유 메모리 시스템에서 거짓 공유를 줄이는 객체-크기 및 호출지-추적 기반 공유 메모리 할당 기법)

  • Lee, Jong-Woo;Park, Young-Ho;Yoon, Yong-Ik
    • Journal of Digital Contents Society
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    • v.9 no.1
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    • pp.77-86
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    • 2008
  • False sharing is a result of co-location of unrelated data in the same unit of memory coherency, and is one source of unnecessary overhead being of no help to keep the memory coherency in multiprocessor systems. Moreover, the damage caused by false sharing becomes large in proportion to the granularity of memory coherency. To reduce false sharing in page-based DSM systems, it is necessary to allocate unrelated data objects that have different access patterns into the separate shared pages. In this paper we propose sized and call-site tracing-based shared memory allocator, shortly SCSTallocator. SCSTallocator places each data object requested from the different call-sites into the separate shared pages, and at the same time places each data object that has different size into different shared pages. Consequently data objects that have the different call-site and different object size prohibited from being allocated to the same shared page. Our observations show that our SCSTallocator outperforms the existing dynamic shared memory allocators. By combining the two existing allocation technique, we can reduce a considerable amount of false sharing misses.

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Development of a Control System for Automated Line Heating Process by an Object-Oriented Approach

  • Shin, Jong-Gye;Ryu, Cheol-Ho;Choe, Sung-Won
    • Journal of Ship and Ocean Technology
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    • v.6 no.4
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    • pp.1-12
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    • 2002
  • A control system for an automated line heating process is developed by use of object-oriented methodology. The main function of the control system is to provide real-time heating information to technicians or automated machines. The information includes heating location, torch speed, heating order, and others. The system development is achieved by following the five steps in the object-oriented procedure. First, requirements are specified and corresponding objects are determined. Then, the analysis, design, and implementation of the proposed system are sequentially carried out. The system consists of six subsystems, or modules. These are (1) the inference module with an artificial neural network algorithm, (2) the analysis module with the Finite Element Method and kinematics analysis, (3) the data access module to store and retrieve the forming information, (4) the communication module, (5) the display module, and (6) the measurement module. The system is useful, irrespective of the heating sources, i.e. flame/gas, laser, or high frequency induction heating. A newly developed automated line heating machine is connected to the proposed system. Experiments and discussions follow.

Development of Performance Evaluation Metrics of Concurrency Control in Object-Oriented Database Systems

  • Jun, Woochun;Hong, Suk-Ki
    • Journal of Internet Computing and Services
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    • v.19 no.5
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    • pp.107-113
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    • 2018
  • Object-oriented databases (OODBs) canbe used for many non-traditional database application areas such as computer-aided design, etc. Usually those application areas require advanced modeling power for expressing complicated relationships among data sets. OODBs have more distinguished features than the traditional relational database systems. One of the distinguished characteristics of OODBs is class hierarchy (also called inheritance hierarchy). A class hierarchy in an OODB means that a class can hand down the definitions of the class to the subclass of the class. In other words, a class is allowed to inherit the definitions of the class from the superclass. In this paper, we present performance evaluation metrics for class hierarchy in OODBs from a concurrency control perspective. The proposed performance metrics are developed to determine which concurrency control scheme in OODBs can be used for a given class hierarchy. In this study, in order to develop performance metrics, we use class hierarchy structure (both of single inheritance and multiple inheritance), and data access frequency for each class. The proposed performance metrics will be also used to compare performance evaluation for various concurrency control techniques.

Design and Implementation of a Transparent Security Infrastructure using Filter and Transformer (필터와 트랜스포머를 이용한 투명한 보안기반의 설계 및 구현)

  • Kim, Yong-Min;Lee, Do-Heon;Noh, Bong-Nam;Choi, Rak-Man;Ine, So-Ran
    • The Transactions of the Korea Information Processing Society
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    • v.5 no.4
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    • pp.975-983
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    • 1998
  • In these days, information communication systems are based on both open distributed computing technologies and object-oriented techniques like inheritance, encapsulation and object reuse to support various system configuration and application. As information systems are interconnected through unsecure networks, the need for the secure information exchange is more critical than before. In this paper, we have designed and implemented a transparent CORBA-basce Security infrastructure with authentication, security context association, access control and security information management to support a secure applications in distributed object environment. SESAME Ver. 4 was adopted as an external security service to manage user privilege attributes and to distribute keys for data encryption, decryption and integrity. Using filter and transformer with an interface to Object Request Broker, it provides a transparent security service to applications. The filter objects are special classes that allow additional parameters to be inserted into messages before they are sent and removed just after they are received. The transformer objects are special classes that allow direct access to the byte stream of every messages for encryption and decryption before it is sent and just after it is received. This study is to implement the access control interceptor(ACI) and the secure invocation interceptor(SII) of secure ORB defined in CORBA using filter and transformer.

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Implementation of the Authorization Model for the Database Server of BADA-III system (바다-III 시스템의 데이타베이스 서버를 위한 권한부여 모델의 구현)

  • Kim, Young-Kyun;Cho, Ok-Ja
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.6 no.3
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    • pp.41-56
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    • 1996
  • Database servers that are used to provide multimedia information services in World Wide Web(WWW) environment have to support the access control mechanism that allows authorized users to access the constructed databases. In this paper, we define an authorization model as well as authorization policies to enforce the proper access control on databases in the BADA-III object-oriented database server and propose an access evaluation algorithm. Also we implement this model and the algorithm in the BADA-III database server. Considering the service environment of the WWW, we expect that database service providers can simply and effectively protect their data using the proposed model.

Spatio-Temporal Index Structure for Trajectory Queries of Moving Objects in Video (비디오에서 이동 객체의 궤적 검색을 위한 시공간 색인구조)

  • Lee, Nak-Gyu;Bok, Kyoung-Soo;Yoo, Jae-Soo;Cho, Ki-Hyung
    • The KIPS Transactions:PartD
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    • v.11D no.1
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    • pp.69-82
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    • 2004
  • A moving object has a special feature that it's spatial location, shape and size are changed as time goes. These changes of the object accompany the continuous movement that is called the trajectory. In this paper, we propose an index structure that users can retrieve the trajectory of a moving object with the access of a page. We also propose the multi-complex query that is a new query type for trajectory retrieval. In order to prove the excellence of our method, we compare and analyze the performance for query time and storage space through experiments in various environments. It is shown that our method outperforms the existing index structures when processing spatio-temporal trajectory queries on moving objects.

Relational Data Extraction and Transformation: A Study to Enhance Information Systems Performance

  • Forat Falih, Hasan;Muhamad Shahbani Abu, Bakar
    • Journal of information and communication convergence engineering
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    • v.20 no.4
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    • pp.265-272
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    • 2022
  • The most effective method to improve information system capabilities is to enable instant access to several relational database sources and transform data with a logical structure into multiple target relational databases. There are numerous data transformation tools available; however, they typically contain fixed procedures that cannot be changed by the user, making it impossible to fulfill the near-real-time data transformation requirements. Furthermore, some tools cannot build object references or alter attribute constraints. There are various situations in which tool changes in data type cause conflicts and difficulties with data quality while transforming between the two systems. The R-programming language was extensively used throughout this study, and several different relational database structures were utilized to complete the proposed study. Experiments showed that the developed study can improve the performance of information systems by interacting with and exchanging data with various relational databases. The study addresses data quality issues, particularly the completeness and integrity dimensions of the data transformation processes.

A Study on the propagation channel modeling for Korean joint tactical Data Link (한국형 합동전술데이터링크 구축을 위한 관한 전파환경 채널 모델링)

  • Lee, Sung-Gu
    • Proceedings of the Korea Information Processing Society Conference
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    • 2012.11a
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    • pp.814-817
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    • 2012
  • It has to secure the reliability for the propagation performance in the physical layer of the products for comprising system in order to satisfy the service quality. The radiowave environment under the actual service circumstance is measured. By using the channel model which models and which it obtains, the performance about the access device tries to be tested under the laboratory environment and there is the object of channel modeling.

Implemetation of STEP Standard Data Interface (SDAI) on Multiple Data Models (이종 데이터 모델에서의 STEP 표준 데이터 인터페이스(SDAI) 구현)

  • 권용국;유상봉
    • The Journal of Society for e-Business Studies
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    • v.3 no.1
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    • pp.1-22
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    • 1998
  • SDAI (Standard Data Access Interface) is an interface specification of accessing various storage systems such as file systems and database management systems for STEP data. Using SDAI, both application program developers and CAD/CAM system developers can be relieved from dealing with STEP physical file or system dependent DBMS operations. In this paper, we present implementations of SDAI on different data models, i.e., relational, extended relational, and object-oriented. In order to implement SDAI, we need to translate the EXPRESS information model into target data models. The schema translation process for three different data models are compared and other implementation issues are discussed.

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