• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.4C
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• pp.476-483
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• 2009

Tracking and detecting targets by the microwave seeker is affected by the clutter reflecting from the earth's surface. In order to detect retreating targets in look-down scenario, which appear in the sidelobe clutter (SLC) region, in the microwave seeker of high pulse repetition frequency (HPRF) mode, it is necessary to understand statistical characteristics of the surface SLC. Statistical analysis of SLC has been conducted for several kinds of the surface using data obtained by the captive flight test of the microwave seeker in the HPRF mode. The probability density function (PDF) fitting is conducted for several kinds and conditions of the surface. PDFs and PDF parameters, which best describe statistical distribution of the SLC power, are estimated. By using the estimated PDFs and PDF parameters, analyses for setting the target-detection thresholds, which give a desired level of target-detection false alarm probability, are made. These analysis materials for statistical characteristics of SLC power and the target-detection threshold can be used in various fields, such as development of a target-detection method, the constant false alarm rate processing.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.39C no.9
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• pp.757-766
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• 2014

To compensate signal loss due to the channel blockage in satellite communication link, we propose a cooperative communication scheme for OTM(On-The-Move) terminal in next generation satellite communication systems. The proposed scheme configures cooperation subnet with adjacent OTM terminal with the help of ground communication equipment. Shared data is spread by orthogonal spreading code, then the spread sequences are transmitted simultaneously. The receiver combines the power of received signals by EGC(Equal gain combining). The OTM terminal blockage channel is modeled by 2-state Markov chain. We evaluate the bit error rate according to the blockage channel of the channel state for the performance analysis of the proposed scheme. As a result, the proposed scheme shows better BER performance than traditional scheme with the help of subset members. In particular, the proposed scheme shows superior performance as the channel block probability is higher. However, as the number of subset members is increasing, there is a constraint because of the higher multiple access interference.

• The Journal of Korean Association of Computer Education
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• v.21 no.2
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• pp.59-71
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• 2018

The purpose of this study is suggesting the direction for improving web accessibility by analyzing the state of abiding by the web accessibility by the centers for teaching and learning support at the education offices in cities and provinces which provide the learning and teaching materials to the K-12 members and the interested people. For this aim, nine centers for teaching and learning support were evaluated. The primary manual evaluation by two experts and the evaluation by 18 users were conducted. The users were comprised of hearing-impaired people, visually-impaired people, brain-disabled people, the elderly, various browser users, and a variety of operating system users. As a result of the analysis, not a single center for teaching and learning support had conformed to web accessibility in the expert evaluation and the user evaluation. As a result of the expert evaluation, the errors regarding web design improvement, HTML source error correction, and provision of alternative measures for the disabled were found. This study is meaningful in the sense that it provided various discussions with regard to the direction of the future web accessibility evaluation based on the improved web accessibility evaluation method.

• Journal of the Korean Society for Library and Information Science
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• v.57 no.1
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• pp.161-182
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• 2023

In the recent cataloging environment, the function of authority data is becoming more important. In Korea, a pilot project for sharing and joint use of the national authority data has been promoted since 2019, and a plan to automatically construct retrospective authority data using national authorities is in progress. This study aims to (1) analyze the results of the pilot project for retrospective authority data jointly promoted by the National Library of Korea and KERIS in 2019, (2) explore methodological limitations and problems in the process, and (3) derive policy proposals for constructing authority data more efficiently. To this end, a university library participating in the pilot project was investigated as a case study. Based on it, the automatic generation rate and accuracy of authority data, and errors and omissions cases and causes were analyzed in detail. As a results of the study, it was found that the quality of union catalogs and bibliographic records had a great influence on automatically constructing authority data, and supplementary methods were needed to minimize these limitations.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.10a
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• pp.457-464
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• 2004

소프트웨어의 품질을 향상시키기 위해 결함을 찾고 시정하는 것을 통제하는데 가장 중요한 요소가 바로 오류/장애/실패(통칭하여 결함(defects)를 효과적으로 추적하는 것이며, 결함을 추적하기 위해서는 효과적인 결함 추적시스템(Defect Tracking System)의 도입이 필요하다. 기존의 결함 추적 시스템은 고객/사용자로부터의 문제보고, 테스팅 기간 중의 결함보고, 변경관리 기능 등을 통합적으로 제공하고 있지 못하다는 점과 테스팅을 포함한 개발과정의 정량적 통제를 위한 데이터를 효과적으로 축적 제공하지 못하고, 더욱이 결함의 근본적인 원인을 찾아 해결할 수 있도록 하기 위한 정보를 효과적으로 제공하지 못하고 있는 문제가 있다. 본 논문에서는 이러한 기존의 결함 추적 시스템의 문제점을 해결하고자 설계/구축되어 현재 사내에서 활용되고 있는 결함관리 시스템인 Promise System을 소개하고자 한다. Promise 시스템은 고객의 불만 및 요구사항, 인스펙션 및 테스팅 시의 결함 및 요구사항에 대하여 각 담당자별로 업무를 할당, 추적할 수 있게 하고, 결함 및 요구사항에 관한 각종 상태정보와 통계 정보를 제공하여, 각 개발 및 테스팅 단계별로 결함 제거 목표의 수립, 정량적 통제, 결함 원인 분석을 통한 프로세스 개선 등을 지원하는 시스템이다.

• Journal of Korean Society of Transportation
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• v.32 no.5
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• pp.452-461
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• 2014

Conventional parking survey has been usually performed by a person, which has a lot of problems such as decreased mobility, data input error, longer time and expensiveness. Therefore, this study attempted to develop an automatic parking survey method using lately commercialized equipments that were highly efficient imagery interpretation equipments, GPS, and infrared lighting fixtures. In addition, this study developed a parking analysis software that enables to modify and save data, and analyze survey data by the automatic parking survey method. When parking survey is conducted using automatic parking survey method, surveying accuracy is influenced by the running speed of a surveying vehicle, the photographing angle of an imagery interpretation equipment, the gap between parking vehicles and the distance of a surveying vehicle to parking vehicles. Therefore, this study drew optimum conditions by testing on each items for accuracy improvement, and developed a parking analysis software for systematic storage and management of parking survey data, supporting the parking analysis and output the parking analysis result.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.2
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• pp.67-78
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• 2006

Local governments began to construct geographic information system to improve government productivity and performance. In support, central government organized a national commission for GIS. The master plan by NGIS has been the base for local government to participate in the construction of GIS at the local level in the under ground facilities management including water and sewers. The challenge faced by sewer facility managers includes controlling 'data accuracy'. The input for sewer data handling for efficient performance in local government requires accurate data. However data manipulation to get the 'good quality' data can be burdensome. Thus, the aim of this research is to provide the appropriate tool to guarantee the high quality of digital data in sewer facility management. It is helpful to pass the data examination by government as well as to insure confidence of decision and data analysis works in local government. In this research, error types of sewer data were classified and pointed the limitation of traditional examination methods. Thus this research suggested more improved method for finding and correcting errors in data input using sewer volume analysis and prediction model as immigrating sewer facility management work to Geographic Information System.

• Korean Journal of Ecology and Environment
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• v.53 no.4
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• pp.380-389
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• 2020

Research on diagnosing and predicting the response of ecosystems caused by environmental changes such as artificial disturbance and climate change is emerging as the most important issue of biodiversity and ecosystem researches. This study aims to clean, standardize, and provide the results of National Ecosystem Survey which should be considered fundamentally in diagnosing and predicting ecosystem changes in the form of dataset. To refine and clean the dataset we developed a simple verification program based on the fifth National Ecosystem Survey Guideline and applied that program to the data from the second (1997~2005), third (2006~2013) and fourth (2014~2018) National Ecosystem Survey. Data quality control processes were implemented including (1) standardization of terminology, (2) similar data table integration, (3) unnecessary attribute and error elimination, (4) unification of different input items, (5) data arrangement in codes, and (6) code mapping for input items. These approaches and methods are the first attempt propose an option for ecological data standardization in Korea. The standardized dataset of National Ecosystem Survey in Korea will be easily accessible, reusable for both researchers and public. In addition, we expect it will contribute to the establishment of diverse environmental policies concerning environmental assessments, habitat conservation, prediction of endangered species distribution and ecological risks due to climate change. The dataset through this study is open freely online via EcoBank (nie-ecobank.kr) which is the first ecological information portal system in Korea developed by National Institute of Ecology.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.36 no.3
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• pp.241-248
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• 2023

The value of experimentally obtained data becomes highest when they are properly analyzed based on valid logics. Many physical and chemical properties such as electrical and magnetic properties, chemical reaction rates, etc. are known to be thermally activated; thus, a proper understanding of thermally-activated processes is of importance. However, there are still a number of papers published with falsely analyzed data. In this contribution, we would like to revisit the meaning of thermally-activated processes, and then reanalyze a data set published misinterpreted. By showing a step-by-step procedure for the reanalysis, we would like to help researchers who may come across such data in the future not to make mistakes in their analysis.

• Fire Science and Engineering
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• v.26 no.1
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• pp.10-15
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• 2012

The fire event occurred in fire proof zone often causes serious electrical problems such as shorts, ground faults, or open circuits in nuclear power plants. These would be directed to the loss of safe shutdown capabilities performed by safety related systems and equipments. The fire event can treat the basic design principle that safety systems should keep their functions with redundancy and independency. In case of a cable fire, operators can not perform their mission properly and can misjudge the situation because of spurious operation, wrong indication or instrument. These would deteriorate the plant capabilities of safety shutdown and make disastrous conditions. In this paper, investigation and cause analysis of cable fire in Nuclear Power Plant, we described the cable fire temperature and functional failure criteria and the cable functional failure temperature evaluation by exposed fire is studied.