• 한국재난정보학회 논문집
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• 제15권1호
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• pp.153-164
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• 2019

연구목적: 본 논문은 물놀이 안전사고로 인한 인명피해를 실효적으로 감소시키기 위한 정책적 및 기술적 측면에서의 개선방안 도출을 목적으로 한다. 연구방법: 먼저 물놀이 안전사고 관리현황 파악 및 민간안전요원에 대한 인터뷰를 실시하였다. 또한 안전요원 및 관리자들을 대상으로 설문조사를 실시하고, 조사 결과를 바탕으로 구체적인 물놀이 안전관리를 위한 정책적 및 기술적 개선 사항을 검토하였다. 연구결과: 검토결과 물놀이 안전사고 방지를 위하여 IoT 인공지능 기술이 적용된 CCTV 및 감시 장치 등 보조적인 지원 방안이 필요하며, 현장 안전감시자의 제한적인 단속권한을 갖는 자격 부여가 필요한 것으로 검토되었다. 결론: 효과적인 물놀이 안전사고 관리를 위해서는 안전요원에 대한 체계적 교육, 단속권한 부여 그리고 감시장비 도입을 통하여 사람과 장비가 융합된 종합적인 물놀이 안전관리 체계가 구축되어야 한다.

• Journal of Microbiology
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• 제45권2호
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• pp.98-104
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• 2007

Chlorophyll ${\alpha}$ concentration and cyanobacterial cell density are regularly employed as dual criteria for determinations of the alert level for cyanobacterial bloom. However, chlorophyll ${\alpha}$ is not confined only to the cyanobacteria, but is found universally in eukaryotic algae. Furthermore, the determination of cyanobacterial cell counts is notoriously difficult, and is unduly dependent on individual variation and trained skill. A cyanobacteria-specific parameter other than the cell count or chlorophyll ${\alpha}$ concentration is, accordingly, required in order to improve the present cyanobacterial bloom alert system. Phycocyanin has been shown to exhibit a strong correlation with a variety of bloom-related factors. This may allow for the current alert system criteria to be replaced by a three-stage alert system based on phycocyanin concentrations of 0.1, 30, and $700\;{\mu}g/L$. This would also be advantageous in that it would become far more simple to conduct measurements without the need for expensive equipment, thereby enabling the monitoring of entire lakes more precisely and frequently. Thus, an alert system with superior predictive ability based on highthroughput phycocyanin measurements appears feasible.

• International Journal of Precision Engineering and Manufacturing
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• 제7권1호
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• pp.30-34
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• 2006

Recently, there has been an increasing demand for computer-vision-based inspection and/or measurement system as a part of factory automation equipment. In general, it is almost impossible to check the fault of all parts, coming from part-feeding system, with only manual inspection because of time limitation. Therefore, most of manual inspection is applied to specific samples, not all coming parts, and manual inspection neither guarantee consistent measuring accuracy nor decrease working time. Thus, in order to improve the measuring speed and accuracy of the inspection, a computer-aided measuring and analysis method is highly needed. In this paper, a computer-vision-based pipe inspection system is proposed, where the front and side-view profiles of three different kinds of pipes, coming from a forming line, are acquired by computer vision. And the edge detection is processed by using Laplace operator. To reduce the vision processing time, modified Hough transform is used with clustering method for straight line detection. And the center points and diameters of inner and outer circle are found to determine eccentricity of the parts. Also, an inspection system has been built so that the data and images of faulted parts are stored as files and transferred to the server.

• 한국산업융합학회 논문집
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• 제23권5호
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• pp.853-863
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• 2020

As the battery ages, the internal resistance of the battery increases, so the loss due to the internal resistance increases at the same charging current, causing the battery temperature to rise, which further accelerates battery aging. Therefore, it is necessary to optimize the charging conditions according to the aging of the battery or the current charge amount, and to accurately estimate this, estimation of the parameters of the equivalent circuit is most important. This paper proposes a new measurement technique that can measure the internal resistance of a battery by analyzing a specific high frequency voltage and current applied to the battery. In addition, in order to test the validity of the proposed measurement technique, the current charging amount was estimated based on the measured internal resistance, and the terminal voltage of the constant current charging mode was automatically set and operated. As a result, good results were obtained regardless of the battery voltage. If this equipment is installed in the charging device, it is believed that it will be of great help in the stability management of the aging reusable battery.

• Design & Manufacturing
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• 제2권6호
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• pp.43-48
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• 2008

Magnesium alloys have given high attention to the industry of light-weigh as automobile and electronics with aluminium, titanium and composite alloys due to their high strength, low specific density and good damping characteristics. But the magnesium contained structures under high temperature have the problems related to creep deformation and rupture life, which is a reason of developing the new material against creep deformation to use them safely. The purpose of this study is to predict the creep deformation mechanism and rupture time of AZ31 magnesium alloy. For this, creep tests of AZ31 magnesium alloy were done under constant creep load and temperature with the equipment including automatic temperature controller with acquisition computer. The apparent activation energy Qc, the applied stress exponent n and rupture life have been determined over the temperature range below 0.5Tm and stress range of 109~187MPa, respectively, in order to investigate the creep behavior. AZ31 Magnesium alloy identify the activation energy for creep deformation and the stress dependence to creep rate at below 0.5Tm, and then investigate the mechanism for creep deformation and creep rupture life of AZ31 Magnesium alloy.

• 한국실천공학교육학회논문지
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• 제3권2호
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• pp.100-105
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• 2011

HIL(Hardware-in-the-Loop) 개념을 적용하면 하이브리드 자동차용 부품의 자동차 환경에서의 특성을 부품을 차량에 장착하지 않고도 평가 할 수 있게 된다. 본 논문에서는 특정 전동기를 하이브리드 자동차용 전동기로 사용하였을 경우 자동차의 구동 특성을 분석할 수 있는 HIL 방식을 구현하기 위한 부품 특성 시험. 구동특성 시뮬레이션, 장치 구성 방법을 설명한다. 시험장치는 자동차 시뮬레이터, 부하장치로 구성되며 시뮬레이션에서 사용된 차량제어기를 직접 차량제어기로 사용하게 된다. 부하장치는 차량의 동적 특성을 모의하게 된다. 특히 기존의 차량의 관성을 모의하기 위한 기계적 관성부하를 사용하지 않고 부하장치를 능동적으로 제어 하여 차량에 적용되었을 경우의 전동기 특성을 구할 수 있다. 시험 전동기가 병렬방식 하이브리드 자동차에 적용되었을 경우의 전동기의 실제 특성을 구할 수 있다. 제안된 방식은 하이브리드 자동차의 구동 특성을 교육하기 위한 교육매체로 사용 될 수 있다.

• 한국정보통신학회논문지
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• 제16권11호
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• pp.2569-2574
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• 2012

초계함(천안함급)에 탑재 된 HMS(Hull Mount Sonar) 장비는 능동모드에 적합하도록 설계 되어 있다. 이에 센서 및 시스템 특성이 어뢰 탐지 주파수 대역에 적당하도록 구성되어 있지는 않다. 이에 초계함에 장착 된 기존 HMS 장비를 이용한 어뢰탐지 기능 구현을 위하여, 초계함 함 별 입력 특성을 분석하고, 입력 주파수 신호에 대한 역보상 회로 설계, 입력 신호 크기에 따른 AGC(Auto Gain Control) 기능 구현 및 함별 신호특성에 따른 대역설정 기능을 통하여 함정 별 특성 및 운용환경 특성에 맞는 어뢰방어시스템을 구현하였다.

• Corrosion Science and Technology
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• 제8권3호
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• pp.119-125
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• 2009

Corrosion assessment has a number of uses but the use considered here is as a precursor to Risk-Based Inspection (RBI) planning. Systematic methods consisting of technical modules of RBI program were used to assess the effect of specific corrosion mechanism on the probability of failure in equipments of petrochemical plants. Especially in part of the damage and corrosion assessment, screening step involved evaluating the combinations of process conditions and construction materials for each equipment item in order to determine which damage mechanisms are potentially active. For general internal corrosion, either API 510 or API 570 was applied as the damage rate in the calculation to determine the remaining life and inspection frequency. In some cases, a measured rate of corrosion may not be available. The technical modules of RBI program employ default values for corrosion, typically derived from published data or from experience with similar processes, for use until inspection results are available. This paper describes the case study of corrosion and damage assessment by using RBI methodology in petrochemical plant. Specifically, this paper reports the methodology and the results of its application to the petrochemical units using the $KGS-RBI^{TM}$ program, developed by the Korea Gas Safety Corporation to suit Korean situation in conformity with API 581 Codes.

• 한국전자통신학회논문지
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• 제6권2호
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• pp.219-224
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• 2011

현재 널리 확산되고 있는 모바일 인터넷 음성 서비스의 품질 관리는 기존의 계측기를 동원한 사후 측정 기반으로는 불가능하다. 보다 체계적인 품질 관리를 위하여 서비스 이용자 단말기에 품질 측정 소프트웨어를 설치하고 서비스 품질을 상시 측정하는 실시간 혹은 사전 품질 관리 체계가 제안된 바 있다. 제안된 품질 관리 체계가 실현되기 위한 필수적인 조건은 품질 측정 소프트웨어의 신뢰성이다. 따라서 본 논문에서는 개발된 품질 측정 소프트웨어의 신뢰성을 검증하기 위한 품질 측정을 실시하였고 그 결과에 대해서 논하고자 한다.

• 교육시설 논문지
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• 제23권1호
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• pp.13-22
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• 2016

Recently, Korea has been established and operated International Schools manifesting to improve the nation's capacity of the foreign languages skill and to cultivate internationally trained professional manpower. In order to achieve the vision of a world-class educational organization, it has to be designed for the facility standards to meet the international accreditation standards. Therefore, the main purpose of this study is to research about basic resources through comparison of facility conditions between public schools in Korea and international accredited schools. By comparing those two different plan drawings are found the following things. First, Schools which established with International Accreditation Standard are prepared detailed criteria for the facility, Furthermore information about the furnishings included, in addition to specific equipments for classes are stated to be prepared. Secondly, it is more effective when special classrooms such as music and science are equipped with various spatial elements, enough educational equipment storage, teacher's study rooms, practical training rooms and student's activity rooms to support various teaching programs and learning efficiently. Lastly, there was a clear tendency that not only hardware but also software standards for the audiovisual room and library have been more enhanced to enable multidisciplinary educational approaches with the recent education training trend.