• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.4
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• pp.447-451
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• 2015

The objective of this study is to predict the structural characteristics of a heat exchanger mounted on an aircraft engine using finite element analysis. The plastic fracture and life of the heat exchanger were estimated by a thermo-mechanical analysis. Tensile tests were conducted under high temperature conditions (700, 800, 900, 1000 K) using five specimens to obtain the mechanical properties of the Inconel 625 tubes. To assess the structural characteristics of the heat exchanger, the full and partial models were applied under the operating conditions given by the thermo-mechanical and inertial load. As a result, the case, tubesheet, flange, and mounting components have a reasonable safety margin to the allowable stress assuming a fatigue strength of Inconel 625 of 10000 cycles under 1000 K.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.11
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• pp.999-1005
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• 2007

In case of an abnormal condition of control surface, the real-time estimation of aerodynamic derivatives are required for the reconfigurable control system to be flight for missions or return to the head office. The goal of this paper is to represent a technique of fault detection to the control surface as a base research to the fault tolerant control system for safety improvement of UAV. The real-time system identification for the fault detection to the control surface was applied with the recursive Fourier Transform and verified through the HILS and flight test. The failures of the control surface are detected by comparing the control derivatives in fault condition with the normal condition. As a result from the flight test, we have confirmed that the control derivatives of fault condition less than about 50% in the normal condition.

• The Journal of the Korea Contents Association
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• v.18 no.1
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• pp.395-402
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• 2018

This study aims to analyze the film "Never Let Me" by human value which is to be realized in the social structure suppressed by the power of life and the power of discipline in Foucault 's power theory. After 18century having changed monarch power holding the power of life-and-death that enforced corporal punishment, bio-power that corrected body and granted ability suitable discipline to people makes people worked like machine. In control of the bio-power, human achieved safe desire that cure disease and prolong life-span and worked as producer goods. School controls body and make people internalized rule using discipline for working bio-power efficiently. There is differentiation between this movie and the other about human clone. The clones adapt role as organ donator without resistance and there is no conflict between original and copy. Instead of preexistence novel and movie that is set in future, it is a form of past retrospect from the 1970s to 1990s. having emotions, They find independence ego and realize value of life in finite living by depending relation or undergoing loss.

• Journal of Biosystems Engineering
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• v.9 no.2
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• pp.81-88
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• 1984

현재 축산농가에서 쉽게 구할 수 있는 곡류, 조사료 및 부산물을 활용하여 사료의 자급율을 높이는 것은 농가의 소득증대를 위하여 바람직한 일이다. 이러한 사료의 자급자족 체계를 위하여 소형이며 조작이 간편한 사료분쇄기가 요구된다. 따라서 농가에 많이 보급되어 있는 5~10 마력 (3.7-7.5 kw)의 동력경운기에 의하여 작동될 수 있는 소형 햄머타입의 사료분쇄기 시작기를 설계 제작하였다. 그리고 시작기의 성능을 분석하기 위하여 보리, 옥수수, 볏짚, 건초를 사료로 하여 시료의 공급율과 스크린의 구멍크기를 변화시켜가며 실험을 수행하였다. 이상과 같은 햄머 밀 시작기의 설계 및 성능시험을 통하여 얻어진 결과를 요약하면 다음과 같다. 1. 시작기의 평균분쇄능력은 보리의 경우 평균입자직경이 543 마이크론일 때 $82.7kg/kw{\cdot}h$였으며, 옥수수의 경우에는 평균입자직경이 408 마이크론일 때 $132.7kg/kw{\cdot}h$였다. 2. 최대 공급율로 분쇄할 때 소요동력은 보리의 경우 1.9kw, 옥수수의 경우 5.3kw, 볏짚의 경우 1.5kw, 건초의 경우 1.6kw을 필요로 하였으며, 5-10 마력(3.7-7.5kw)의 동력경운기로 개발된 햄머 밀을 작동함에는 별 문제가 없는 것으로 분석되었다. 3. 시작기로 시료를 분쇄할 때 곡류 분쇄는 물론 조사료 분쇄도 가능한 것으로 분석되었다. 4. 시작기에 의해 시료를 분쇄했을 때 분쇄물의 평균온도 상승폭은 $7.2-10.0^{\circ}C$였다. 이러한 온도는 분쇄물의 영양소 파괴및 저장상의 안정성을 고려할 때 안전한 범위의 온도상승으로 판단되었다. 5. 원료공급율과 스크린 구멍크기가 분쇄량과 분쇄정도에 5% 수준에서 유의성 있는 영향을 미쳤다.

• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.1
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• pp.133-138
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• 2022

In this paper we present the system we produced to help workers at logistic centers and prevent accidents, in which they could get hurt. As a base we use the main control device, named Arduino uno, which measures the weight by using load cells. When operating with the system, by placing object on it, the system measures the weight of the object and keeps the highest point at the same height by lowering its board. This improves the convenience while placing and removing objects from the board. If the weight of the placed object is exceeding the set value the board will also lower itself to secure the safety. By using a line tracer system, the objects are being moved only on a set route with the goal to make it even more comfortable to use.

• Review of KIISC
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• v.33 no.4
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• pp.23-29
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• 2023

대부분의 임베디드 시스템은 기계장치와 전자기기 장치가 함께 작동되는 물리 장치로써, 이기종 네트워크, 복잡한 보안체계 등을 고려하여 가상화 기반 사이버훈련 환경이 구성되어야 한다. 또한, 차량을 대상으로 물리적인 실험환경에서 모의침투 등 사이버훈련을 수행한다는 것은 교통사고를 비롯한 안전사고 발생에 있어 위험이 존재한다. 본 논문에서는 가상 개발환경에서의 공격 기반 차량용 사이버훈련 프레임워크를 제안하고자 한다. 먼저, 공격 기반 차량용 사이버훈련 프레임워크의 작동은 자동 활성화되는 가상의 CAN 네트워크 인터페이스로 시작된다. 가상의 CAN 네트워크 인터페이스는 가상 머신에서 간단한 부트스트랩 명령어 실행을 통해 파이썬 패키지와 Ubuntu 서비스 목록 설치 명령이 자동으로 실행되면서 설치된다. 이후 내부 네트워크 시뮬레이터와 공격모듈과 관련된 UI가 자동으로 Ubuntu Systemd에 의해 백그라운드에서 실행되어 시작과 동시에 준비 상태를 유지하게 된다. 사이버훈련 UI 내 공격 모듈은 사용자에 의한 공격 선택 및 파라미터 셋팅 이후 차량의 이상 상태를 사이버훈련 UI에 다시 출력되게 된다. 본 논문에서 제안하는 가상 개발환경 기반의 차량용 사이버훈련 프레임워크는 자율주행 차량 사고의 위험이나 다른 특수한 제약 없이 사용자의 학습 경험을 확장시킬 수 있다. 또한, 기존의 가상화 기반 사이버훈련 교육 콘텐츠와는 달리 일반 사용자들이 접근하기 쉬운 형태로 확장 개발이 가능하다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.21 no.1
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• pp.83-90
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• 2015

The car ferry operating between the mainland and the island plays an important role on transportation of goods and passengers. Therefore, the improvement of efficiency and safety as well as economic factor are importantly considered in the development process of car ferry. Double-ended car ferry is already popularized because of its economic feasibility and convenience for passenger in Europe and developed countries, and the demand is booming in domestic. In this paper, dynamic characteristics of propeller shaft and strength in double-ended car ferry are analyzed using campbell diagram and modal analysis. Based on the analysis of dynamic characteristics, resonant phenomenon and critical speed are stable when occurring the propeller shaft vibration due to forward and reverse propeller shaft working.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.9 s.351
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• pp.135-141
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• 2006

In order to prevent traffic accident, it is very important that the driver regulates the location of rear view mirror using the automatic seat regulation system which guarantees the maximum vision of the possibility for accuracy. In order to solve this problem the paper deals with the automatic seat control system which guarantees comfortable and safe seating and good visual field. Also a automatic car seat control algorithm has been developed to regulate the back mirror. Particularly, the automatic seat control algorithm function for the air bag operation in case of an accident has been added depending on passengers weight. Moreover when the driver passes a dangerous area an algorithm has been developed which gives the driver a naming sign and has been simulated in a ubiquitous environment. The simulation result proved that the Intelligence analysis for traffic accidents can reduce franc accidents more than 25% than the currently existing methods.

• Journal of the Korean Society of Marine Environment & Safety
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• v.18 no.5
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• pp.439-445
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• 2012

Only the sand carriers fitted with hopper doors can remove their hatch covers in current regulations. However, there is no sand carriers fitted with hopper doors in korea. Through the analysis of accidents, inspection of equipment installed on ships, and evaluation of stability and seakeeping performance concerning the sand carriers, it is expected that the current exemption requirement is modified for hatch covers for sand carriers. As the result, this paper proposed the removal of hatch covers and be fitted by tarpaulin instead to protect water ingress into the holds. This can be done by making the holds smaller designed to be filled full until the top of the hold without exceeding loadline. Also, the bilge pumps should have the sufficient capacity of pumping water out in the early stage of sand-water mixture to wetted condition in approximately 1 hour and be operationally ready in every voyage conditions.

• Journal of Digital Convergence
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• v.18 no.10
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• pp.239-252
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• 2020

By using text mining, we explore the factors responsible for an increase in SUV preference. We collected 32,679 posts related to SUVs from "Bobaedream," the largest online automobile community in South Korea, and applied the LDA topic model. While previous studies have explained the SUV boom as an individual's risk aversion strategy from crime, the result shows that the topic of 'Safety' appears to be an important factor in the SUV discourse in the context of a car accident and high-speed driving situation. To conclude, the consumption of SUVs in Korean society serves as a mean to prevent anxiety and danger to individuals when driving. We insist that decreasing social trust, caused by an increase in inequality, underlies the perception of risk on the road.