• Title/Summary/Keyword: Large tables

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A Study on the Development and Maintenance of Embedded SQL based Information Systems (임베디드 SQL 기반 정보시스템의 개발 및 관리 방법에 대한 연구)

  • Song, Yong-Uk
    • The Journal of Information Systems
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    • v.19 no.4
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    • pp.25-49
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    • 2010
  • As companies introduced ERP (Enterprise Resource Planning) systems since the middle of 1990s, the databases of the companies has become centralized and gigantic. The companies are now developing data-mining based applications on those centralized and gigantic databases for knowledge management. Almost of them are using $Pro^*C$/C++, a embedded SQL programming language, and it's because the $Pro^*C$/C++ is independent of platforms and also fast. However, they suffer from difficulties in development and maintenance due to the characteristics of corporate databases which have intrinsically large number of tables and fields. The purpose of this research is to design and implement a methodology which makes it easier to develop and maintain embedded SQL applications based on relational databases. Firstly, this article analyzes the syntax of $Pro^*C$/C++ and addresses the concept of repetition and duplication which causes the difficulties in development and maintenance of corporate information systems. Then, this article suggests a management architecture of source codes and databases in which a preprocessor generates $Pro^*C$/C++ source codes by referring a DB table specification, which would solve the problem of repetition and duplication. Moreover, this article also suggests another architecture of DB administration in which the preprocessor generates DB administration commands by referring the same table specification, which would solve the problem of repetition and duplication again. The preprocessor, named $PrePro^*C$, has been developed under the UNIX command-line prompt environment to preprocess $Pro^*C$/C++ source codes and SQL administration commands, and is under update to be used in another DB interface environment like ODBC and JDBC, too.

Binary Search Tree with Switch Pointers for IP Address Lookup (스위치 포인터를 이용한 균형 이진 IP 주소 검색 구조)

  • Kim, Hyeong-Gee;Lim, Hye-Sook
    • Journal of KIISE:Information Networking
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    • v.36 no.1
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    • pp.57-67
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    • 2009
  • Packet forwarding in the Internet routers is to find out the longest prefix that matches the destination address of an input packet and to forward the input packet to the output port designated by the longest matched prefix. The IP address lookup is the key of the packet forwarding, and it is required to have efficient data structures and search algorithms to provide the high-speed lookup performance. In this paper, an efficient IP address lookup algorithm using binary search is investigated. Most of the existing binary search algorithms are not efficient in search performance since they do not provide a balanced search. The proposed binary search algorithm performs perfectly balanced binary search using switch pointers. The performance of the proposed algorithm is evaluated using actual backbone routing data and it is shown that the proposed algorithm provides very good search performance without increasing the memory amount storing the forwarding table. The proposed algorithm also provides very good scalability since it can be easily extended for multi-way search and for large forwarding tables

Database Table Management and Input/output Design System on the Web (웹 기반 서버 데이터베이스 테이블 관리 및 입출력 형태 정의 시스템)

  • 한순희
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.3 no.2
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    • pp.433-445
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    • 1999
  • Today's Web tends to change from simple guideline to more complex information Provider based on large amount of data, enabling a better understanding of the objects. It provides various information retrieval techniques. Therefore, these data have to be stored and maintained in a database system for efficiency and consistency. But database system absolutely requires systematic and consistent management techniques. As a consequence, a high trained and well-educated person should do it. In this paper, we design and implement a tool for easy and reliable database table creation and management on the web. If users log in this system, they can get a list of tables created by themselves and will find a hyper link per each table. Futhermore, they can view and manage it's contents.

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A Design of Adder and Multiplier on GF ( $2^m$ ) Using Current Mode CMOS Circuit with ROM Structure (ROM 構造를 갖는 電流방식 COMS 回路에 依한 GF ( $2^m$ ) 上의 演算器 설계)

  • Yoo, In-Kweon;Seong, Hyeon-Kyeong;Kang, Sung-Su;Kim, Heung-Soo
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.25 no.10
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    • pp.1216-1224
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    • 1988
  • In this paper, it is presented element generation, addition, multiplication and division algorithm over GF ($2^m$) to calculate multiple-valued logic function. The results of addition and multiplication among these algorithms are applied to the current mode CMOS circuits with ROM structure to design of adder and multiplier on GF ($2^m$). Table-lookup and Euclid's algorithm are required the computation in large quentities when multiple-valued logic functions are developed on GF ($2^m$). On the contrary the presented operation algorithms are prefered to the conventional methods since they are processed without relation to increasing degree m in the general purpose computer. Also, the presened logic circuits are suited for the circuit design of the symmetric multiplevalued truth-tables and they can be implemented addition and multiplication on GF ($2^m$) simultaueously.

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Solution Methods for OD Trip Estimation in Stochastic Assignment (확률적 통행배정하에서 기종점 통행량추정 모형의 개발)

  • Im, Yong-Taek
    • Journal of Korean Society of Transportation
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    • v.24 no.4 s.90
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    • pp.149-159
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    • 2006
  • Traditional trip tables are estimated through large-scale surveys such as household survey, roadside interviews, and license Plate matching. These methods are, however, expensive and time consuming. This paper presents two origin-destination (OD) trip matrix estimation methods from link traffic counts in stochastic assignment, which contains perceived errors of drivers for alternatives. The methods are formulated based on the relation between link flows and OD demands in logit formula. The first method can be expressed to minimize the difference between observed link flows and estimated flows, derived from traffic assignment and be solved by gradient method. The second method can be formulated based on dynamic process, which nay describe the daily movement patterns of drivers and be solved by a recursive equation. A numerical example is used for assessing the methods, and shows the performances and properties of the models.

On the Feasibilty of Milled Sanders as a New Extender for Plywood Glue (합판접착제용(合板接着劑用) 미세목분증량제(微細木粉增量劑)에 관(關)한 연구(硏究))

  • Ahn, Kee-Woo
    • Journal of the Korean Wood Science and Technology
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    • v.1 no.2
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    • pp.3-10
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    • 1973
  • This study was carried out to examine the characeristics of waste sanders(S)from. plywood and pre-finishing plywood surface sanding and double saw finishing, as a new extander in urea-formaldehyde resin(UFR) in plywood adhesive, and to focus, adhesive strength using the glue extended with milled sanders(MS) as extender, leveling the optimum amount of MS to be added, and examining the physical properties of glue extended MS & S. Also economical good feasibility of substitution for wheat flour(WF) with MS as a new extender is analyzed and presented in details. Selecting three standard samples of 80, 100 and 180 mesh, sorking them in distilled water at $20^{\circ}C$, 24 hours, redrying at $105^{\circ}C$ and rescreening the sample with standard screen, again, the 3 samples of 80, 100, and 180 mesh are passed 23 percent through 80 mesh sander standard sample 27 percent through on 100 mesh and only 10.9 percent through 180 mesh, respectively. The particle size of retained parts are greater in size of redried form. It seems undoubtly that particles to be extended in glue are got swollen and become greater in size and coarser in shape. The shape of fresh S particles are irregular thin needle with small scale, as shown in Figure 5. PFS are so finer than plywood S that only 9.8 percent of the S retained on 100 mest screen, 24. 30 percent on 100-160 mesh, and 65.9% on 160-180 mesh. But particle size of the fresh S is large enough to make the viscosity of glue direct extended with S too high to apply it glue spreader. The glue extended with milled sanders(MS). 3 hours milled PFS or 6 hours milled plywood S, having particle sizes shown in Tables 7 and 8, as ratio of Reain/MS/WF/water: 100/8/8/10, indicate good viscosity of 16 to 24 ps, as shown in Figure 5, for applying direct to glue spreader, have high tensile-shear strength (adhesive strength), 102.4 kp/$cm^2$, and 94 percent wood failure.

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AOZDV(Ad Hoc On-demand Zone and Distance-Vector) : A Routing Protocol with Novel Zone Mechanism in Wireless Ad hoc Networks (무선 Ad hoc 망의 새로운 Zone 기법을 적용한 AOZDV(Ad Hoc On-demand Zone and Distance-Vector) 라우팅 프로토콜)

  • Kim Yong-Woo;Choi Sung-Jae;Lee Hong-Ki;Song Joo-Seok
    • Journal of KIISE:Information Networking
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    • v.33 no.4
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    • pp.299-309
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    • 2006
  • In Mobile ad hoc networks, AODV is one of the famous on-demand routing protocol, which use the routing tables in the nodes if possible, or Route Discovery Process (RDP) is triggered to find a new route. However increasing the traffic of RDP causes dropping of the network performance in the large size of ad hoc networks. In this paper, we propose a novel routing protocol, named as AOZDV (Ad hoc On-demand Zone and Distance-Vector Routing), which enhances the AODV protocol with zone routing. AOZDV creates a Zone with neighbor nodes of the source/destination using traffic and power information, and utilizes Destination-Vector Table for internal routing in the Zone. We show by simulations that AOZDV can reduce the occurrence rate of route fail and RDP caused by route fail compared to existing routing protocols such as DSR and AODV.

Inverted Indexes for XML Updates and Full-Text Retrievals in Relational Model (관계형 모델에서 XML 변경과 전문 검색을 지원하기 위한 역 인덱스 구축 기법)

  • Cheon, Yun-Woo;Hong, Dong-Kweon
    • The KIPS Transactions:PartD
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    • v.11D no.3
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    • pp.509-518
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    • 2004
  • Recently there has been some efforts to add XML full-text retrievals and XML updates into new standardization of XML queries. XML full-text retrievals plays an important role in XML query languages. of like tables in relational model an XML document has complex and unstructured natures. We believe that when we try to get some information from unstructured XML documents a full-text retrieval query is much more convenient approach than a regular structured query XML update is another core function that an XML query have to have. In this paper we propose an inverted index to support XML updates and XML full-text queries in relational environment. Performance comparisons exhibit that our approach maintains a comparable size of inverted indexes and it supports many full-text retrieval functions very well. It also shows very stable retrieval performance especially for large size of XML documents. Foremost our approach handles XML updates efficiently by removing cascading effects.

Proposal and Evaluation of Metrics for Measurement of Documents Reliability (개발산출물의 신뢰성 측정을 위한 메트릭의 제안과 평가)

  • Nam, Ki-Hyun;Han, Pan-Am;Yang, Hae-Sool
    • The KIPS Transactions:PartD
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    • v.8D no.3
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    • pp.247-256
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    • 2001
  • Software is developing toward having more large scale and many functions day by day. Also, user’s requirements level for software is being high, especially, requirements for software quality is being high continuously. Methods which can satisfy such User’s requirements is being studied in various viewpoint. First of all, study about quality evaluation system and methodology is energetically in progress in viewpoint to improve quality of software by feed-back software quality evaluation result to developers. In this paper, we define metrics according to a system and developed quality measurement tables according to internal characteristics system of quality characteristics, subcharacteritics, internal characteristics for reliability between quality characteristics of international standard, ISO/IEC 9126 about software quality. And we propose evaluation results about development products using internal characteristics.

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The stress analysis of a shear wall with matrix displacement method

  • Ergun, Mustafa;Ates, Sevket
    • Structural Engineering and Mechanics
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    • v.53 no.2
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    • pp.205-226
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    • 2015
  • Finite element method (FEM) is an effective quantitative method to solve complex engineering problems. The basic idea of FEM for a complex problem is to be able to find a solution by reducing the problem made simple. If mathematical tools are inadequate to obtain precise result, even approximate result, FEM is the only method that can be used for structural analyses. In FEM, the domain is divided into a large number of simple, small and interconnected sub-regions called finite elements. FEM has been used commonly for linear and nonlinear analyses of different types of structures to give us accurate results of plane stress and plane strain problems in civil engineering area. In this paper, FEM is used to investigate stress analysis of a shear wall which is subjected to concentrated loads and fundamental principles of stress analysis of the shear wall are presented by using matrix displacement method in this paper. This study is consisting of two parts. In the first part, the shear wall is discretized with constant strain triangular finite elements and stiffness matrix and load vector which is attained from external effects are calculated for each of finite elements using matrix displacement method. As to second part of the study, finite element analysis of the shear wall is made by ANSYS software program. Results obtained in the second part are presented with tables and graphics, also results of each part is compared with each other, so the performance of the matrix displacement method is demonstrated. The solutions obtained by using the proposed method show excellent agreements with the results of ANSYS. The results show that this method is effective and preferable for the stress analysis of shell structures. Further studies should be carried out to be able to prove the efficiency of the matrix displacement method on the solution of plane stress problems using different types of structures.