• 한국산업융합학회 논문집
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• 제23권2_1호
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• pp.115-124
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• 2020

In wireless power transfer (WPT) system, the conventional compensation topologies only can provide a constant current (CC) or constant voltage (CV) output under their resonant conditions. It is difficult to meet the CC and CV hybrid charging requirements without any other schemes. In this study, a switching hybrid topology (SHT) is proposed for CC and CV electric vehicle (EV) battery charging. By utilizing an additional capacitor and two AC switches (ACSs), a double-side LCC (DS-LCC) and an inductor and double capacitors-series (LCC-S) topologies are combined. According to the specified CC and CV charging profile, the CC and CV charging modes can be flexibly converted by the two additional ACSs. In addition, zero phase angle (ZPA) also can be achieved in both charging modes. In this method, because the operating frequency is fixed, without using PWM control, and only a small number of devices are added, it has the benefits of low-cost, easy-controllability and high efficiency. A 3.3-kW experimental prototype is configured to verify the proposed switching hybrid charger. The maximum DC efficiencies (at 3.3-kW) of the proposed SHT is 92.58%.

• 전기전자학회논문지
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• 제25권1호
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• pp.95-100
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• 2021

조선소에서 선체 블록과 용접 피더의 위치를 알면 작업자의 위치 정보를 쉽게 얻을 수 있다. 이 데이터는 작업장 안전 모니터링 시스템 구축에 매우 유용하다. 그러나 선체 구조와 용접 공정의 특수성 때문에 작업장에 고정 통신망을 적용하기 어렵다. 본 연구에서는 전용 통신선을 대신할 수 있는 유도 전력선 통신을 선체블록과 같은 금속매체에 적용하는 기술을 검토하였다. 용접기의 전원 케이블에 설치할 유도 결합기로 페라이트 코어를 사용하였고, 금속 블록의 지지대에 체결할 결합기로 나노 결정질 코어를 적용하였다. 제안된 커플러는 COMSOL AC/DC 모듈로 3차원 모델링 하였고 동작 원리를 시각화하기 위하여 유한 요소 해석을 수행하였다. 알루미늄 프로파일을 사용한 금속블록 통신 성능 테스트에서 용접 전극의 블록 접촉으로 통신 채널이 형성되었을 때 대역폭은 6 Mbps 이상 유지되었다.

• 한국축산식품학회지
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• 제41권2호
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• pp.312-323
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• 2021

The purpose of this study was to use 1H nuclear magnetic resonance (1H NMR) to quantify taste-active and bioactive compounds in chicken breasts and thighs from Korean native chicken (KNC) [newly developed KNCs (KNC-A, -C, and -D) and commercial KNC-H] and white-semi broiler (WSB) used in Samgye. Further, each breed was differentiated using multivariate analyses, including a machine learning algorithm designed to use metabolic information from each type of chicken obtained using 1H-13C heteronuclear single quantum coherence (2D NMR). Breast meat from KNC-D chickens were superior to those of conventional KNC-H and WSB chickens in terms of both taste-active and bioactive compounds. In the multivariate analysis, meat portions (breast and thigh) and chicken breeds (KNCs and WSB) could be clearly distinguished based on the outcomes of the principal component analysis and partial least square-discriminant analysis (R2=0.945; Q2=0.901). Based on this, we determined the receiver operating characteristic (ROC) curve for each of these components. AUC analysis identified 10 features which could be consistently applied to distinguish between all KNCs and WSB chickens in both breast (0.988) and thigh (1.000) meat without error. Here, both 1H NMR and 2D NMR could successfully quantify various target metabolites which could be used to distinguish between different chicken breeds based on their metabolic profile.

• Ocean Systems Engineering
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• 제12권1호
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• pp.87-142
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• 2022

An analysis for the computation of Fatigue Damage Index (FDI) under the effects of the various combination of the ocean loads like random waves, current, platform motion and VIV (Vortex Induced Vibration) for a certain design water depth is a critically important part of the analysis and design of the marine riser platform integrated system. Herein, a 'Computer Simulation Model (CSM)' is developed to combine the advantages of the frequency domain and time domain. A case study considering a steel catenary riser operating in 1000 m water depth has been conducted with semi-submersible. The riser is subjected to extreme environmental conditions and static and dynamic response analyses are performed and the Response Amplitude Operators (RAOs) of the offshore platform are computed with the frequency domain solution. Later the frequency domain results are integrated with time domain analysis system for the dynamic analysis in time domain. After that an extensive post processing is done to compute the FDI of the marine riser. In the present paper importance is given to the nature of the current profile and the VIV. At the end we have reported the detail results of the FDI comparison with VIV and without VIV under the linear current velocity and the FDI comparison with linear and power law current velocity with and without VIV. We have also reported the design recommendations for the marine riser in the regions where the higher fatigue damage is observed and the proposed CSM is implemented in industrially used standard soft solution systems (i.e., OrcaFlex^*TM and Ansys AQWA^**TM), Ms-Excel^***TM, and C++ programming language using its object oriented features.

• 한국측량학회지
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• 제24권3호
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• pp.261-269
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• 2006

광산 개발 후 자연환경과 유사한 지형으로의 복원 및 복구에 대한 필요성이 부각되고 있어 사후 관리를 위하여 원 지형과 개발중인 지형에 대한 특성 비교가 필요하며, 효율적인 복원계획을 위한 개발 진행에 따른 지형의 추이 분석이 요구되고 있다. 본 연구는 GIS를 이용하여 년별 광산개발에 따른 지형의 추이 현황을 비교 분석하고자 하였다. 항공사진측량으로 수치화 된 캐드 자료중 년도별로 등고선 자료를 분류하고 각각 불규칙삼각망으로 생성하였다. 수치지형모형인 불규칙삼각망을 통해 종 횡단면을 작성하여 변화량이 많은 지점들을 판별할 수 있었으며, 불규칙삼각망을 래스터로 변환하여 각 셀별 고도 값을 연산함으로써 2000년부터 2002년과 2003년까지 광산개발로 인한 지형변화량을 분석한 결과 $11,094,460m^3$가 절토되고 절토량의 46%인 $5,127,968m^3$이 성토되었다. 또한 채굴에 따른 년도별 절 성토 지역의 표면 변화 양상을 정량적 및 시각적으로 분석할 수 있었다. 따라서 광산개발에 따른 년별 추이 현황 비교는 채광이 완료되는 지역의 경우 성토를 통해 최대한 과거 지형에 근접하도록 설계할 수 있도록 광산 추가개발 및 복원계획에 대한 자료로 사용가능 할 것이다.

• 대한예방한의학회지
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• 제19권2호
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• pp.103-112
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• 2015

Objective : To evaluate the status of mobile personal health records (mPHR) applications of Atopic Dermatitis, assessing general characteristics, information content, features of PHR content and functions. Method : Searches were conducted from Android's Google Play and iOS's App Store. Main criteria used to include mPHRs were: providing health information of PHR function of Atopic Dermatitis; operating in Korean or English; for human. Selected mPHRs were analyzed considering general characteristics, information contents, data elements, and application features. Results : 19 applications were included in this study. 15 were providing health information. Data elements of information included general information, symptom, diagnosis, treatment, prevention, management and FAQ. No single application contained all seven data elements. Only Eight applications had PHR function. In the features analysis, one PHR applications contained all eight PHR functional features; saving profile function, profiles supported, password, import data, export data, information provided, progress chart and push-up alarm. Conclusion : mPHR is an emerging health care technology. The majority of existing mPHR applications only provide one-way information. Application designed to help users and doctors to exchange mutual information was the only one. Also, there was no application that can record the Traditional Korean Medicinal treatment information. However, as the mobile market continues to expand it is likely that more comprehensive mPHRs will be developed in the near future. New advancements in mobile technology can be utilized to enhance Tranditional Korean Medical health care.

• 한국정보과학회논문지:소프트웨어및응용
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• 제34권9호
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• pp.817-827
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• 2007

유비쿼터스 시대가 도래하면서 거대한 양의 컴퓨팅 서비스 및 장치들은 언제 어디서나 사용자의 요구에 반응하게 된다. 더불어 사용자 특성에 따른 기호에 맞는 개인화된 서비스가 요구된다. 사람의 위치 이동에 따른 동적인 다양한 서비스 제공을 위해서는 사용자의 개입을 최소화하여야 한다. 그리고 사용자 관심 여부에 맞춘 서비스 장치 및 동자 모드들이 자동적으로 결정되어야 할 것이다. 본 논문에서는 유비쿼터스 환경에서 사용자의 요구에 가장 근접한 맞춤형 서비스의 제공을 위하여 다음의 네 가지 단계로 분산 지능형 에이전트 기술을 제안한다. 첫째, 유비쿼터스 환경의 인프라구조인 스마트한 공간을 가상의 시뮬레이터로 설계하여 물리적 자원 및 컴퓨팅 객체 환경을 모델링 한다. 둘째, 분산된 에이전트들의 상호협력을 통한 서비스 목적 달성을 위해서 FIPA 표준안에 따르는 멀티 에이전트 기반 구조를 이용한 지능형 에이전트 기술을 연구한다. 셋째, 에이전트간의 메시지 통신을 이용하여 서비스 적용이 가능한 스마트 공간으로의 사용자의 위치 이동에 따른 이기종 환경에서의 자율적인 서비스 발견 및 구성 방안을 제안한다. 넷째, 휴대가 손쉬운 이동 장비에 사용자의 프로파일 정보를 저장함으로써 언제, 어디에서나 에이전트의 모니터링을 통한 개인화 서비스 방법을 연구한다. 따라서 일반적인 자동화된 서비스 구동 이상의 개인 특성에 맞는 고품질의 서비스를 제공한다.

• 정보관리학회지
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• 제26권2호
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• pp.83-103
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• 2009

1990년부터 2003년까지 운용된, Computer Interchange of Museum Information (CIMI)는 국제 박물관 사회에 메타데이터 산업표준 채택의 개념을 고안해내고, 소개하는 역할을 했다. CIMI 컨소시엄은 이러한 기본임무를 넘어서, 표준구조 (Standard Framework), 프로파일, 테스트베드 (testbeds), 주요 메타데이터 저작물, 다운로드가능 무료 메타데이터 소프트웨어나 프로토콜등을 생산했고, 새로운 프로젝트에 대한 산업적 안내 및 지원을 제공했다. 하지만, CIMI의 가장 중요한 성취물은 아마도 표준기반 접근의 중요성과 유용성과 CIMI 표준 프레임워크의 실행의 필요성에 대한 강조일 것이다. 이로 인해CIMI의 가동기간동안, 박물관들은 각자의 요구를 충족시키기 위해 새로운 표준/모델의 고안이나 소프트웨어의 개발에 따른 비용부담없이, 메타데이터 모델 혹은 표준의 이용법을 습득하는 것으로 각자의 이득을 거둬 들일 수 있었다. 비록 CIMI의 가동은 2003년으로 중단되었지만, 박물관 관련 메타데이터 응용과 연구에 미친 유산과 영향력은 막대하다고 할 수 있다. 본 논문은 CIMI가 박물관 메타데이터 분야 다음 세대 개발자들에게 남긴 유산을 살펴보고 예상되는 후속프로젝트 및 연구를 살펴본다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.86-95
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• 2006

Brillouin backscatter is a type of reflection that occurs when light is shone into an optical fibre. Brillouin reflections are very sensitive to changes in the fibre arising from external effects, such as temperature, strain and pressure. We report here several case studies on the measurement of strain using Brillouin reflections. A mechanical bending test of an I beam, deployed with both fiber optic sensors and conventional strain gauge rosettes, was performed with the aim of evaluating: (1) the capability and technical limit of the DTSS technology for strain profile sensing; (2) the reliability of strain measurement using fiber optic sensor. The average values of strains obtained from both DTSS and strain gauges (corresponding to the deflection of I beam) showed a linear relationship and an excellent one-to-one match. A practical application of DTSS technology as an early warning system for land sliding or subsidence was examined through a field test at a hillside. Extremely strong, lightweight, rugged, survivable tight-buffered cables, designed for optimal strain transfer to the fibre, were used and clamped on the subsurface at a depth of about 50cm. It was proved that DTSS measurements could detect the exact position and the progress of strain changes induced by land sliding and subsidence. We also carried out the first ever distributed dynamic strain measurement (10Hz) on the Korean Train eXpress(KTX) railway track in Daejeon, Korea. The aim was to analyse the integrity of a section of track that had recently been repaired. The Sensornet DTSS was used to monitor this 85m section of track while a KTX train passed over. In the repaired section the strain increases to levels of 90 microstrain, whereas in the section of regular track the strain is in the region of 30-50 microstrain. The results were excellent since they demonstrate that the DTSS is able to measure small, dynamic changes in strain in rails during normal operating conditions. The current 10km range of the DTSS creates a potential to monitor the integrity of large lengths of track, and especially higher risk sections such as bridges, repaired track and areas at risk of subsidence.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.150.1-150.1
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• 2014

Showerhead is used as a main part in the semiconductor equipment. The face plate flatness should remain constant and the cleaning performance must be gained to keep the uniformity level of etching or deposition in chemical vapor deposition process. High operating temperature or long period of thermal loading could lead the showerhead to be deformed thermally. In some case, the thermal deformation appears very sensitive to showerhead performance. This paper describes the methods for robust design using computational fluid dynamics. To reveal the influence of the post distribution on flow pattern in the showerhead cavity, numerical simulation was performed for several post distributions. The flow structure appears similar to an impinging flow near a centered baffle in showerhead cavity. We took the structure as an index to estimate diffusion path. A robust design to reduce the thermal deformation of showerhead can be achieved using post number increase without ill effect on flow. To prevent the showerhead deformation by heat loading, its face plate thickness was determined additionally using numerical simulation. The face plate has thousands of impinging holes. The design key is to keep pressure drop distribution on the showerhead face plate with the holes. This study reads the methodology to apply to a showerhead hole design. A Hagen-Poiseuille equation gives the pressure drop in a fluid flowing through such hole. The assumptions of the equation are the fluid is viscous-incompressible and the flow is laminar fully developed in a through hole. An equation can be expressed with radius R and length L related to the volume flow rate Q from the Hagen-Poiseuille equation, $Q={\pi}R4{\Delta}p/8{\mu}L$, where ${\mu}$ is the viscosity and ${\Delta}p$ is the pressure drop. In present case, each hole has steps at both the inlet and the outlet, and the fluid appears compressible. So we simplify the equation as $Q=C(R,L){\Delta}p$. A series of performance curves for a through hole with geometric parameters were obtained using two-dimensional numerical simulation. We obtained a relation between the hole diameter and hole length from the test cases to determine hole diameter at fixed hole length. A numerical simulation has been performed as a tool for enhancing showerhead robust design from flow structure. Geometric parameters for the design were post distribution and face plate thickness. The reinforced showerhead has been installed and its effective deposition profile is being shown in factory.