• Journal of Korean Society of Industrial and Systems Engineering
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• v.30 no.1
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• pp.59-65
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• 2007

HPI (High-speed Portable Internet) system which provides high speed internet services is going to be commercialized soon. Since HPI provides simultaneously four different service types such as UGS (Unsolicited Grant Service), rtPS (real time Polling Service), nrtPS(non-real time Polling Service), and BE (Best Effort) under different QoS (Quality of Service) requirements and limited wireless channel resources, efficient packet scheduling mechanisms are necessary to increase the utilization of channels as well as to satisfy the various QoS requirements. This study regards the traffic data to be served as time series and proposes a new packet scheduling algorithm based on the nonparametric statistical test. The performance of the newly proposed algorithm is evaluated through the simulation analysis using a simulator that can evaluate the performance of packet scheduling mechanisms under various values of system parameters and measures such as packet delay time, data transmission rate, number of loss packets, and channel utilization.

• Journal of Applied Reliability
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• v.3 no.1
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• pp.73-82
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• 2003

Reliability Centered Maintenance(RCM) was initially developed for the commercial aviation industry in the late 1960s and now is equally applicable to a variety of equipment other than aircraft. RCM is a method for establishing a preventive maintenance program which will efficiently and effectively allow the achivement of the the required safety and availability levels of equipment and structures. RCM provides for the use of a decision logic tree to identify applicable and effective preventive maintenance requirements for equipment and structures according to the safety, maintenance requirements for equipment and structures according to the safety, operational and economic consequences of identifiable failures, and the degradation mechanism, reponsible for the those failures. The end result of working through the decision logic is a judgement as to the necessity of performing a maintenance task. In this paper, we provide guiding principles based on IEC 60300-3-11 for RCM analysis methods and operational method of structure and equipment.

• Journal of the Korea Safety Management & Science
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• v.19 no.1
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• pp.115-122
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• 2017

This study analyzed that the standard of school supplies affects the satisfaction of certification. Safety requirements of school supplies in the Republic of Korea is enforced by court duty certification. Therefore, a test was conducted to compare the safety requirements of the United States and Europe and the survey was conducted to know how much manufacturers and importers are satisfied with the certification. To prepare management measures for harmful substances contained in children's product, XRF(X-ray Fluorescence Spectrometry) is utilized to analyze lead(Pb) and cadmium(Cd) in PA(paint), SP(sheet) and PVC(Poly Vinyl Chloride). The results of comparative analysis of ICP(inductively coupled plasma) is analyzed statistically with measured values.

• Journal of the Korea Society of Computer and Information
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• v.20 no.10
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• pp.113-119
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• 2015

In this paper, we propose an efficient freedom of information and Information access right which improves transparent and speedy administration process. To build open Information, we scrutinize that causes of non access right and change of civil service consciousness, attitude for open information by effectively open system circumstances. The Important thing is basic information that is available to the public through an agency's FOIA Reference Guide, all agencies must notify potential FOIA requesters of the formal rules and requirements for the making and handling of FOIA request, through their FOIA regulations. The characteristics of this paper focused on Information access right, causes of non access right and proposed policy. In this paper, The author emphasize are as follows: first, to examine freedom of information' necessity and problem that scrutinize a theoretic analysis, second, to understand civil servant's attitude for the freedom of information, third, to suggest action plan and agenda for the better of Good Governance and Democracy of information.

• Journal of the Korean earth science society
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• v.41 no.4
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• pp.391-404
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• 2020

This study identified and examined earth science education department programs in Korea. Major courses provided by 11 universities and their course requirements were analyzed, and the main research results are as follows. First, many basic courses, other major requisite, and elective courses are provided in geology, astronomy, and atmospheric science. oceanography, geophysics, earth environmental science, and natural disaster and energy resources had fewer major requisite courses provided in addition to basic courses, and few elective courses were offered. Second, many courses in science education focused on earth science, while others focused on general science and there were few courses that covered education theory regarding the specific subject. Third, science course application requirements emphasized the understanding of science in general or of earth science specifically. From the above results, additional studies are proposed to reflect on the current state and supplement these programs.

• IE interfaces
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• v.14 no.2
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• pp.198-204
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• 2001

The ISO 9000 family of international quality management standards were revised on 15 December 2000. The ISO 9001:2000 standard is used for certification/registration and contractual purposes by organizations seeking recognition of their quality management system(QMS). We summarize key contents changed in ISO 9000:2000 family standards. To comply with ISO 9001:2000, we analyze the current QMS for steel outfit industry, using audit results from ISO 9001:1994 for seven steel outfit firms during last three years. We investigate statistical relationships between ISO 9001:2000 and ISO 9001:1994 requirements from a three dimensional contingency table with audit results. We observe that the importance of requirements of the ISO 9001:2000 sections makes a difference between companies.

• Journal of Satellite, Information and Communications
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• v.7 no.2
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• pp.87-96
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• 2012

In this research, we describe recent technologies and system requirements of the passive microwave radiometer used in Earth observation satellites. And we classify types of microwave radiometer system for Earth observation satellites according to observation targets and ways to scan and discuss a design method. Also, requirements of passive radiometer for Earth observation missions in the latest practical examples used and developed are analyzed in this research.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.20 no.2
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• pp.7-12
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• 2012

A landing gear absorbs the impact energy during the touchdown and it generally consists of an oleo-pneumatic shock absorber and structural components. It should be designed not only to satisfy the static and fatigue strength requirements but to have the sufficient shock absorbing efficiency. The design loads and shock absorbing performance are to be validated by tests, which is required by MIL Spec and FAR, etc. This paper presents the development procedures from the design requirements to the qualification tests and technical points to be considered, with examples of the helicopter landing gear development.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.20 no.3
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• pp.28-34
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• 2012

The recent transition to Performance Based Navigation in aviation enhances the accuracy of aircraft position, safety and efficiency in air traffic operations by using satellite-based navigation system such as GNSS. However, intentional interferences with GNSS signal as well as ones coming from natural phenomena such as solar storm increase. GNSS have very low power and therefore their signals are more susceptible to interferences than ground-based navigation signals. This paper introduces requirements of alternative positioning, navigation and timing(APNT) system and relevant technologies when the GNSS signals are not valid.

• Proceedings of the Korea Institutes of Information Security and Cryptology Conference
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• 2003.12a
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• pp.317-323
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• 2003

본 논문에서는 정보보호제품의 평가 수요 증가에 적극적으로 대처하고, 양질의 평가서비스 제고를 위한 CCRA 요구사항 수준의 평가기관 요구사항을 분석 및 도출한다. 이를 위하여 CCRA의 평가기관 요구사항 및 ISO/IEC17025의 요구사항을 분석하였으며, NIST Handbook 150, NIST Handbook150-20 등 CAP 국가들의 평가기관 인정과 관련된 표준문서들을 연구하여 각 CAP 국가들의 평가기관 요구사항들을 분석하고 평가기관의 평가자 양성을 위한 교육 및 자격 부여 프로그램들을 비교 분석하였다.