• 에너지공학
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• 제23권3호
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• pp.116-124
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• 2014

고온에서 운전되는 플랜트에서는 열변형에 의한 배관 사고를 예방하고 배관계통의 우선 검사관리 부위의 선정을 위해 배관 시스템하중 해석을 수행하는 경우가 많다. 본 연구에서는 국내 한 공정플랜트에서 설계변경에 따라 반응기와 반응기 사이에 추가 설치된 연결배관을 대상으로 배관 시스템응력해석을 수행하였다. 특히 배관에 일반적으로 설치되는 하중행거(hanger) 이외에 열팽창을 흡수하는 신축이음(expansion joint)이 함께 설치된 경우의 배관 특성을 연구하였다. 이를 위해 배관 응력을 형성하는 구조적 요인의 영향을 평가하기 위해 배관계에 포함된 행거와 신축이음이 비정상적으로 작동되는 경우도 가정하여 해석하였다. 추가적인 인입라인이 있는 경우도 해석을 수행하였다. 정상 운전 시 배관계의 시스템 응력 결과와 비정상적인 운전 경우의 해석결과를 비교하여 각각 배관요소의 역할을 연구하였다.

• 융합보안논문지
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• 제19권4호
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• pp.13-22
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• 2019

본 연구는 사이버작전을 전문적으로 수행하지 않는 비(非)사이버작전부대 장교들을 위한 교육체계를 개발하고 방향성을 제안하기 위한 연구이다. 사이버작전을 합동작전으로 수행하기 위해서는 비(非)사이버작전부대 장교들도 사이버작전을 알아야하나 이들을 위한 교육체계는 현재 군(軍)에는 없으며, 이에 대한 선행연구 또한 거의 없어 해당 분야의 연구가 필요하다. 따라서, 비(非)사이버작전부대 장교 교육체계는 사전에 실시한 관련 문헌연구를 기반으로, 교육체계를 구성할 수 있는 5가지 항목 즉, 교육의 필요성, 교육대상, 교육목표 및 내용, 교육과정에 관한 사항을 개발하였다. 또한, 관련 전문가들에게 델파이방법으로 각 항목의 타당성을 확인하였다. 그 결과, 일부 향상의 필요성도 보였으나, 전체적으로 적합함을 보였다. 향후에는 이 연구를 바탕으로 세부 교육프로그램 개발이 개발될 수 있다.

• 한국생산제조학회지
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• 제22권3_1spc호
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• pp.509-517
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• 2013

This paper presents upgraded equipment to assist a patient in rehabilitating of their knee-joint by themselves. A new automatic mechanism is suggested and developed in order to add functions for enforcing the leg muscles, which were absent in previous rehabilitation machines. Using the Pro-engineer software, we analyze the displacements and speeds of several moving points of the equipment during various planned exercises. In addition, an appropriate control panel for operation is developed. Three motors andthree motor drivers are used in a tilting part for the ankle joint, sliding guide part for the knee joint, and up-down moving part for the whole leg. Finally, various newly upgraded motions can be generated by controlling the three motors simultaneously. we show that by using this equipment, we can adjust the proper length of the equipment according to the user's height and the intensity of the rehabilitation exercise.

• Journal of Astronomy and Space Sciences
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• 제40권2호
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• pp.79-88
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• 2023

On Aug. 4, 2022, at 23:08:48 (UTC), the Korea Pathfinder Lunar Orbiter (KPLO), also known as Danuri, was launched using a SpaceX Falcon 9 launch vehicle. Currently, KPLO is successfully conducting its science mission around the Moon. The National Aeronautics and Space Administration (NASA)'s Deep Space Network (DSN) was utilized for the successful flight operation of KPLO. A great deal of joint effort was made between the Korea Aerospace Research Institute (KARI) and NASA DSN team since the beginning of KPLO ground system design for the success of the mission. The efficient utilization and management of NASA DSN in deep space exploration are critical not only for the spacecraft's telemetry and command but also for tracking the flight dynamics (FD) operation. In this work, the top-level DSN interface architecture, detailed workflows, DSN support levels, and practical lessons learned from the joint team's efforts are presented for KPLO's successful FD operation. Due to the significant joint team's efforts, KPLO is currently performing its mission smoothly in the lunar mission orbit. Through KPLO cooperative operation experience with DSN, a more reliable and efficient partnership is expected not only for Korea's own deep space exploration mission but also for the KARI-NASA DSN joint support on other deep space missions in the future.

• 전기전자학회논문지
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• 제16권3호
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• pp.235-243
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• 2012

In this study, we developed two legged multi-joint robot by using wireless servo motor that was applied by wireless sensor network technology, which is widely used recently, and performed an experiment of walking method of two legged multi-joint robot. We constructed the star network with servo motors which were used at each joint of two-legged robot. And we designed the robot for operation by transmission of joint control signal from main control system or by transmission of the status of each joint to the main control system, so it operates with continuously checking the status of joints at same time. We developed the humanoid robot by using wireless digital servo motor which is different from existing servo motor control system, and controlled it by transmitting the information of angles and speeds of robot joints to the motor(node) as a feedback through main control system after connecting power and setting up the IDs to each joint. We solved noisy problem generated from wire and wire length to connection point of the control device by construction of the wireless network instead of using existing control method of wiring, and also solved problem of poor real time response to gait motion by controlling the position with continuous transmission of control signals to each joint. And we found that the effective control of robot is able by performing the simulation on walking motion in advance with the developed control algorithm which was downloaded into installed memory. Also we performed the stable walking with two-legged robot by attaching pressure sensor to robot sole. And we examined the robot gait operated by application of calculated algorithm on robot movement to each joint. In this study, we studied the method of controlling robot gait motion by using wireless servo motors and measured the torque applied to each joint, and found that the developed wireless servo motor by ZigBee sensor network offers easier control of two legged robot gait and better circuit configuration of it than the existing wired control system could do.

• Nuclear Engineering and Technology
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• 제37권2호
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• pp.151-158
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• 2005

Advanced nuclear power plants are generally large complex systems automated by computers. Whenever a rare plant emergency occurs the plant operators must cope with the emergency under severe mental stress without committing any fatal errors. Furthermore, The operators must train to improve and maintain their ability to cope with every conceivable situation, though it is almost impossible to be fully prepared for an infinite variety of situations. In view of the limited capability of operators in emergency situations, there has been a new approach to preventing the human error caused by improper human-machine interaction. The new approach has been triggered by the introduction of advanced information systems that help operators recognize and counteract plant emergencies. In this paper, the adverse effect of automation in human-machine systems is explained. The discussion then focuses on how to configure a joint human-machine system for ideal human-machine interaction. Finally, there is a new proposal on how to organize technologies that recognize the different states of such a joint human-machine system.

• 한국통신학회논문지
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• 제38B권10호
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• pp.775-784
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• 2013

이동통신 사업자들은 자신의 망 총소유비용을 줄이면서 데이터 폭증에 대처하기 위한 다양한 기술적인 대책 들을 강구하고 있다. 이 논문에서는 그러한 기술적인 대책의 하나로써 클라우드 기지국이란 새로운 기지국 구조에서 조정 다중점 송수신 운용에 따른 시스템 용량 및 이동성 성능에 관련된 모의실험 결과를 도출한다. 그 결과는 조정 다중점 송수신이 적용되는 클라우드 기지국의 규모 및 적용 영역에 따라 시스템 용량 및 이동성 성능도 개선될 수 있다는 것을 관찰할 수 있었으며 이러한 상호 인과 관계들은 실제 이동통신 사업자의 망 운용에 있어서 하나의 실용적 지침을 제공할 수 있다.

• Smart Structures and Systems
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• 제32권5호
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• pp.309-318
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• 2023

The appropriate maintenance of highway roads is critical for the safe operation of road networks and conserves maintenance costs. Multiple methods have been developed to investigate the surface of roads for various types of cracks and potholes, among other damage. Like road surface damage, the condition of expansion joints in concrete pavement is important to avoid unexpected hazardous situations. Thus, in this study, a new system is proposed for autonomous expansion joint monitoring using a vision-based system. The system consists of the following three key parts: (1) a camera-mounted vehicle, (2) indication marks on the expansion joints, and (3) a deep learning-based automatic evaluation algorithm. With paired marks indicating the expansion joints in a concrete pavement, they can be automatically detected. An inspection vehicle is equipped with an action camera that acquires images of the expansion joints in the road. You Only Look Once (YOLO) automatically detects the expansion joints with indication marks, which has a performance accuracy of 95%. The width of the detected expansion joint is calculated using an image processing algorithm. Based on the calculated width, the expansion joint is classified into the following two types: normal and dangerous. The obtained results demonstrate that the proposed system is very efficient in terms of speed and accuracy.

• 정보화연구
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• 제11권2호
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• pp.187-199
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• 2014

미국, 영국, 나토는 불확실한 미래 합동작전을 위한 합동 능력을 구축하기 위해 합동 개념을 발전시켜 적용하고 합동능력 관리체계를 개발하여 운영하고 있다. 그 중 미군은 능력을 기반으로 전력을 기획하여, 예산을 편성하고, 집행하여 평가는 PPBEE 체계를 운영하고 있다. 또한 미군은 합동능력영역(JCA), 합동과제목록(UJTL) 등을 중심으로 합동능력관리체계(JCAMS)를 개발하여 운영하고 있다. 최근 한국군도 이러한 능력 개념을 도입하고 관리하기 위한 시스템을 개발하기 위해 노력하고 있다. 본 논문은 미군의 합동능력관리체계를 참고하여 한국군에 적합한 능력관리 통합메커니즘을 제안한다. 제안한 통합메커니즘을 통하여 우리군은 효율적이고 효과적으로 합동능력 관리체계(JCMS)를 구축 할 수 있을 것이다.

• 한국군사과학기술학회지
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• 제18권6호
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• pp.743-754
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• 2015

FASCAM is a newly introduced mean against enemy fire power and supposed to be scattered on base areas in front of a tunnel so as to deter maneuver and shooting of enemy artilleries. However, for its characteristics different from conventional munitions, only a few studies have been undertaken on operations system using this new measure. In this research, we propose a procedure to describe and analyze mathematically an operation system for suppression of enemy fire power using FASCAM. Two suggested simulation methods, impact point generation and density integration, both can describe the actual operation rationally and each has advantages of its own respectively. Further, we demonstrated an example analysis to derive an optimal suppression plan based on the proposed procedure.