• Nuclear Engineering and Technology
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• 제54권4호
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• pp.1482-1494
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• 2022

Power conversion cycles (Subcritical Steam, Supercritical Steam, Open Air Brayton, Recuperated Air Brayton, Combined Cycle, Closed Brayton Supercritical CO₂ (sCO₂), and Stirling) are evaluated for land-based nuclear microreactors based on technical maturity, system efficiency, size, cost and maintainability, safety implications, and siting considerations. Based upon these criteria, Air Brayton systems were selected for further evaluation. A brief history of the development and applications of Brayton power systems is given, followed by a description of how these thermal-to-electrical energy conversion systems might be integrated with a nuclear microreactor. Modeling is performed for optimized cycles operating at 3 MW(e) with turbine inlet temperatures of 500 ℃, 650 ℃ and 850 ℃, corresponding to: a) sodium fast, b) molten salt or heat pipe, and c) helium or sodium thermal reactors, coupled with three types of Brayton power conversion units (PCUs): 1) simple open-cycle gas turbine, 2) recuperated open-cycle gas turbine, and 3) recuperated and intercooled open-cycle gas turbine. Aeroderivative turboshaft engines employing the simple Brayton cycle and two industrial gas turbine engines employing recuperated air Brayton cycles are also analyzed. These engines offer mature technology that can facilitate near-term deployment with a modest improvement in efficiency.

• 디지털산업정보학회논문지
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• 제8권3호
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• pp.49-55
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• 2012

Recently, with the rapid development of android-based smartphones, it is becomes a major security issue that the case of Android platform is an open platform. so it is easy to be a target of mobile virus penetration and hacking. Even there are a variety of security mechanisms to prevent the vulnerable points of the Android platform but the reason of most of the security mechanisms were designed at application-level that highly vulnerable to the attacks directly to the operating system or attacks using the disadvantages of an application's. It is necessary that the complementary of the android platform kernel blocks the kernel vulnerability and the application vulnerability. In this paper, we proposed a secure system using linux-based android kernel applied to LIDS(Linux Intrusion Detection and Defense System) and applied a smart phone with s5pc110 chip. As a result, the unauthorized alteration of the application was prevented with a proposed secure system.

• 한국산학기술학회논문지
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• 제14권9호
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• pp.4447-4454
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• 2013

2011년 10월 국내 최초로 다목적댐 저수지에 100kW급 수상태양광발전 상용화 실증 플랜트가 합천댐에 설치되었다. 수상태양광발전 설비는 육상에 설치하는 태양광발전 설비와는 달리 수상부유체, 계류장치, 수중케이블 등 설치에 많은 어려움이 있다. 특히 수상이라는 환경적 제약으로 인해 육상 태양광 시공 방법으로 공정 관리를 할 수 없는 많은 변수가 속출한다. 수상태양광발전의 구조체는 수상태양광 모듈 및 기타 전기설비를 수상에 부상시키기 위한 설비로서 바람이나 태풍 등 기상환경에 견뎌야 하고 수질에 악영향을 미치지 말아야하며 시공성, 경제성 등 종합적인 고려가 필요하다. 본 논문에서는 100kW 수상태양광 시공사례를 바탕으로 수상태양광의 구조체, 계류장치, 수중케이블, 전력설비 및 원격감시제어시스템의 시공기술에 대한 기초자료를 제공하였다. 본 연구에서 시공된 100kW 수상태양광은 현재 평균 설비이용률 15%로 운영중에 있다.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.1388-1395
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• 2009

In March 2007, Korea's Ministry of Construction & Transportation (MOCT) established "Guidelines on the Computerization and Use of Geotechnical Investigation Results," which took effect as official instructions. The 2007 Geotechnical Information DB Construction Project is underway as a model project for a stable geotechnical information distribution system based on the MOCT guidelines, accompanied by user education on the geotechnical data distribution system. This study introduces a geotechnical data entry system characterized by the standardization of the geotechnical investigation form, the standardization of metadata for creating the geotechnical data to be distributed, and the creation of borehole space data based on the world geodetic system according to the changes in the national coordinate system, to define a unified DB structure and the items for the geotechnical data entry system and to computerize the field geotechnical investigation results using the MOCT guidelines. In addition, the present operating status of the geotechnical data entry system and entry data processing statistics are introduced through an analysis of the model project, and the problems of the project are analyzed to suggest improvements. Education on, and the implementation of, the model project for the geotechnical data entry system, which was developed via the standardization of the geotechnical investigation results form and the metadata for institutions showed that most users can use the system easily. There were problems, however, including those related to the complexity of metadata creation, partial errors in moving to the borehole data window, partial recognition errors in the installation program for different computer operating systems, etc. Especially, the individual standard form usage and the specificity of the person who enters the geotechnical information for the Korea National Housing Corporation, among the institutions under MOCT, required partial improvement of the geotechnical data entry system. The problems surfaced from this study will be promptly addressed in the operation and management of the geotechnical data DB center in 2008.

• 한국안전학회지
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• 제39권1호
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• pp.41-54
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• 2024

Efforts to reduce on-site safety incidents have expanded, leading to active research in this domain. However, a systematic analysis to improve the utility of technology is lacking. In this study, we conducted a survey on the various institutional and technical improvement measures to promote the application of smart construction safety technology over three years after the implementation of the "Smart Safety Equipment Support Project." The results showed that financial constraint was the primary obstacle in the adoption of this innovation. Fostering a flexible environment in the utilization of management fees and financial support of projects was determined to aid in the extensive application of the technology. Ensuring cost efficiency and user-friendliness were principally necessary for technical enhancements in the smart construction safety technology. Technologies, such as VR/AR safety education, real-time location tracking, wearable devices, and innovation on streamlining safety-related work efficiency, had been anticipated to contribute to on-site safety. Operating a smart safety control center was expected to be beneficial in the systematic securing of data and reduction of safety blind spots. Effective methods had been suggested to overcome the barriers that hindered the development and application of smart construction safety technology. This study facilitates in the technological improvements in this field.

• 한국측량학회지
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• 제15권2호
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• pp.141-148
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• 1997

지속적인 PC의 발전 및 이에 반비례한 가격의 하락, Windows 95. Windows N/T로 이어지는 PC운영체제의 확장은 소규모 단지의 경우 PC에서도 도시기반시설관리정보체계의 운영가능성을 신중히 모색케 하고 있다. 이와 같은 점을 고려하여 AutoCAD를 이용하여 한국토지공사의 단지기반시설 업무인 pipe-based도시기반시설-상수, 우수, 오수-및 도로의 도면정보와 속성정보를 PC상에서 동시에 관리할 수 있는 자료자동화 시스템을 구축하였고, 향후 구축 방향 및 문제점을 논하였다.

• 한국산학기술학회논문지
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• 제21권6호
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• pp.432-439
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• 2020

제동력 향상을 위해 인 보드 브레이크 시스템이 적용된 한국형 전술차량 일부 운용 부대에서 제동 시 차체 떨림 현상인 브레이크 저더가 확인되었다. 차량 제동 시 발생되는 심한 진동은 주행 안정성을 저하시키며 나아가 사고로 이어질 수 있다. 이를 방지하기 위해 본 연구에서는 브레이크 저더가 확인된 차량을 대상으로 고장 분석을 통해 근본원인을 분석하고, 나아가 진동 전달 메커니즘 분석을 통해 진동의 주요 전달 경로를 파악함으로써 개선 가능 인자를 도출하였다. 분석 결과 전술차량에서 확인된 제동 시 차체 떨림은 냉간 저더 현상으로 브레이크 디스크의 과도한 흔들림 조건에서 녹 및 이물유입에 따라 디스크 두께 변동이 증가하여 발생됨을 확인하였다. 또한 이러한 진동은 전달계에 대한 구조 개선을 통해 저감할 수 있음을 확인하였다. 이에 본 연구에서는 각각의 인자들에 대해 개선 방안을 제시하고, 비교시험을 통해 검증함으로써 그 효과성을 확인하였다. 끝으로 본 연구를 통해 도출된 개선안은 차기 군용차량 개발 시 활용할 수 있을 것으로 기대된다.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2022년도 춘계학술대회
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• pp.207-208
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• 2022

최근 디지털 기술이 발전하면서 조선해양분야에 새롭게 도입되는 도입하는 연구사례가 늘고 있으며 업계에서도 관련 장비 및 서비스가 개발되고 있다. 새로운 장비가 개발되고 출시하기 이전에 우선 검증과정을 거쳐야한다. 조선해양분야에서는 우선 육상에서 시뮬레이션 시험 또는 환경시험을 통해 장비를 검증하고 있다. 하지만 육상시험만 진행하면 실운용환경에서의 검증데이터가 부족하다. 본 논문에서는 실운용 환경에서의 검증을 위한 실증시나리오 개발에 있어 고려할 수 있는 사항에 대해 기술한다.

• 한국항공운항학회지
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• 제14권1호
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• pp.70-74
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• 2006

Cospas-Sarsat, an international satellite system for search and rescue, started operating in early 1980's and has been credited with saving thousands of lives since then. Hundreds of thousands of aviators, mariners and land users worldwide are equipped with Cospas-Sarsat distress beacons, which could help save their lives in emergency situations anywhere in the world. This paper outlines the evolution of the system and describes how satellites are constantly circling the globe monitoring for rescue signals, while tracking stations on six continents receive the satellite signals, compute the locations of the distress events and forward the calls for help to the appropriate rescue authorities. Therefore, this paper points out the importance of developing of technologies of Hybrid Aviation Wireless SAR Equipment and also proposes to make it localized.

• 농업과학연구
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• 제37권1호
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• pp.113-121
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• 2010

Land consolidation ratio for rice paddy fields reached to 64.7% as of 2008 in Korea, and this also accelerated automation of field machinery. Especially, research on autonomous tractors has been continuously conducted. Tillage is one of the labor-, energy-, and time-consuming field operations. Most important requirements for autonomous tractors would be travelling path planning and electronic system to control the tractor to follow the path. The instruction of computer was required to conduct the tillage operation in field with unmanned traveling tractor. This instruction was coincidently used in the control of the traveling path and the motion of tractor. The objectives of the study were 1) to characterize and model tillage operating sequence, turning pattern, and 2) to develop tillage path formation programs for autonomous tractor and evaluate the performance.