• Polymer(Korea)
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• v.25 no.1
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• pp.25-32
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• 2001

The kinetics of ester interchange reaction of dimethyl naphthalate(DMN) with ethylene glycol(EG) has been studied in the range of 180-200 $^{\circ}C$ using zinc and manganese catalysts. The reaction was performed in a semibatch reactor under nonisothermal condition and the degree of reaction was calculated from experimental data of methanol removal rate and reaction temperature. As a reaction model, both the functional group model and the molecular species model were applied and analysed. In case of zinc catalyst, the ratio of reaction rate of methyl hydroxyethyl naphthalate(MHEN) with EG on that of DMN with EG is about 1.4, whereas in case of manganese catalyst the ratio is about 4.3, which implies that the reaction rate is quite dependent on the type of catalyst. In case of zinc catalyst, the reaction order of catalyst concentration on either DMN or MHEN and EG is less than 1, whereas in case of manganese catalyst, the reaction order is larger than 1. The activation energy for zinc and manganese catalyst, irrespective of the type of molecular species, e.g., DMN and MHEN, were found to be 25000 and 28750 cal/mol, respectively. As a result of comparing two reaction model, the molecular species model fits well for the experimental data.

• International Journal of Highway Engineering
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• v.19 no.2
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• pp.153-165
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• 2017

PURPOSES : With the increasing number of older drivers in an aging society, there is a growing need for research and planning on traffic safety for the older drivers using an improved road geometry design. This study also proposed a modified urban road interchange design, which aims to keep the older drivers away from accident-prone and high-traffic areas of the city. METHODS : In this study, we examined accident data records of older drivers to identify accident-prone zones and intersections; we studied the road geometry at these zones and analyzed if it was an underlying cause for higher number of accidents. Based on the research and subsequent analysis, we suggested plans for improvement of road geometry design at these intersections. RESULTS :By studying historic data and analyzing factors that affect the likelihood of accidents of vehicles driven by older drivers and after studying suitable traffic accident prediction models, we identified the major variables that need to be modified at accident-prone intersections, such as the width of a left turn lane at an intersection and the radius of the right turn lane at a street corner. The results have a significance probability of less than 0.001 and a 95% confidence level. To improve safety at the identified intersection, this study suggests the installation of a left-turn-lane-shaped Positive Offset and a right-turn-lane-shaped Slip Lane concept and an adjustment of intervals between intersections.

• Journal of Korean Society of Transportation
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• v.26 no.4
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• pp.29-40
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• 2008

Although a good understanding of the relationship between highway traffic accidents and highway geometric features is fundamental in highway design and safety, the relationship is not well understood quantitatively. The overall goal of this paper is to formulate a reliable statistical model fitting to historical highway accident data. The model can be used to estimate the effect of road design elements on safety for the practical purposes of highway design applications. En route to achieving this goal, a number of specific research objectives were accomplished: investigate the major design elements affecting highway safety; review the existing modeling approaches in order to assess the relationship between safety and highway design features; and formulate a statistical model fitting to the accident data in order to estimate the interchange ramp junction accident frequency of rural highways.

• Proceedings of the Korea Database Society Conference
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• 1999.06a
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• pp.383-392
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• 1999

오늘날의 의사결정을 지원하는 시스탬에 있어서 데이터 웨어하우스가 널리 활용되고 있다. 이러한 데이터웨어 하우스를 개발하는데 있어서 메타 데이터가 필수적인 요소로 활용되고 있다. 한편. 메타 데이터 연합 (Meta Data Coalition)에서 제정한 Metadata Interchange Specification (MDIS)는 이러한 메타 데이터의 표준으로 널리 활용되고 있다. 본 연구는 이러한 표준을 기반으로 한 메타 데이터 스키마를 제시하고 있다. 실제적인 개발에서 이러한 표준은 핵심웨어하우스 계층, 적용 계층, 사용자 탐험 계층 및 비즈니스 계층으로 구성되어 있다. 이러한 메타 데이터 스키마를 적용한 실제 시스템의 프로토타입을 본 연구에서 구현해 보았다.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2007.02a
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• pp.72-79
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• 2007

OMG's Common Warehouse Metamodel is now a single data warehouse metadata standard. Interchange of metadata between data warehousing tools and metadata repositories made easy and convenient by using CWM. In this paper, we present the origin, importance and architecture of CWM, and offer an application case.

• Journal of the Korean Home Economics Association
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• v.36 no.12
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• pp.115-127
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• 1998

The purpose of this study intended to fully understand from the point of view of the elderly parent's satisfaction in the living to adult children. The subject of this study was elderly parent's over 55 years old whom live in Iksan. The sample was composed of 146 cases. The data were analyzed using SPSS statistic program. The major findings were as follows : 1) The effective indicator was related economic parts ; earns, the cost of living, educational background, sex, affection. 2) The affection related between elderly parent's and adult children was found to be high and the conflict between them was found to be low. 3) The economic interchange between elderly parent's and their adult children was influenced by religion, cohabitance with adult children. The effective indicator was conflict and dependent emotions. The serviced interchanges was influenced by spouse, sex, earns.

• The Transactions of the Korea Information Processing Society
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• v.7 no.12
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• pp.3840-3847
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• 2000

Electronic Industries Association has set a standard format called CDIF(CASE Data Interchange Format) for exchanging information between CASE tools from 1991. If data used on a CASE tool is represented in CDIF format, then any other CASE tools can use the data by translating CDlF format into their own format. In order to do so, each CASE vendor must provide a translator program from CDIF to its own data format or from its own data to CDIF format. In this thesis, we have implemented a source code generator for translating CASE data format into CDIF format only if they provide how data is stored. This automatic program generator generates CDIF statements using data format used in CASE tools, meta information about stored data and CDIF meta information. In the thesis, the automatic program generator has been implemented with Java and Oracle DBMS with JOBC interface in Sun O/S environment.

• Proceedings of the Korean Information Science Society Conference
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• 1998.10a
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• pp.427-429
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• 1998

VAN EDI의 단점인 폐쇄성과 비용을 극복하기 위해서 제안된 인터넷 EDI를 구현한다. 인터넷 EDI의 구현 방법인 인터넷 메일 기반 EDI와 웹 기반 EDI의 장점을 통합하여 웹에서의 통합적인 기업간의 전자상거래 솔루션을 지원하기 위한 웹에서의 인터넷 메일기반 EDI를 설계하고 구현하고 보안 요소를 추가한다.

• Proceedings of the Korean Information Science Society Conference
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• 2002.04b
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• pp.94-96
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• 2002

본 논문에서는 EDI(Electronic Data Interchange)와 WorkFlow 시스템에서 가지고 있는 비즈니스 룰 (Business Rule)을 논리 프로그램인 Prolog를 이용해서 각 비즈니스 룰을 분석하고 각각의 프로세스를 완전한 수행을 할 수 있는 시스템을 설계한다.

• Digital Contents
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• no.9 s.64
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• pp.101-105
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• 1998

이 코너는 데이터베이스 관련 표준화 활동중에서 ISO와 IEC의 합동기술위원회(JTC1), SC32 Data Management and Interchange(데이터 관리 및 교환)의 표준화 활동과 데이터베이스 단체표준을 제정하는 데이터베이스 표준총회의 활동을 중심으로 매월 소개하고자 한다. 이번호는 지난 7월 7일부터 11일까지 호주 브리스베인에서 열린 JTC1/SC32 총회의 회의 내용과 제3차 JTC1/SC32 전문위원회 회의 내용, 제6차 데이터베이스 표준화 전문위원회 회의 내용을 게재한다.