• 한국인터넷방송통신학회논문지
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• 제20권2호
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• pp.117-122
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• 2020

본 논문에서는 두 대의 X-대역 안테나를 활용한 시험을 통해 복수의 레이다가 적용되는 함정 통합마스트용 다기능위상배열 레이다의 인접 안테나 개구면 간 전자파 간섭 영향성을 확인하였다. 두 안테나는 시험을 위해 설계 된 통합마스트를 모사한 치구에 배치하였으며, 본 형상을 모델링하여 안테나 빔 조향 시 전자파 영향성을 전자파 해석 도구를 활용하여 분석하였다. 또한, 시험적 분석을 위해 6 가지 시험 시나리오를 설정하였으며, 각 시험 시나리오는 무반향 챔버에서 진행하였다. 시험 시 안테나 #1은 펄스 파형 송신 하였으며, 안테나 #2 부터 수신된 신호는 수신장치를 통해 광 데이터로 저장하여 신호를 분석하였다. 분석 결과를 바탕으로 통합마스트에서 복수의 다기능 레이다를 인접하여 운용 시 전자파 간섭 영향성을 제시한다.

• 한국화재소방학회논문지
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• 제19권1호
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• pp.70-89
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• 2005

수평통로의 천장 아래로 확산되는 연기의 냉각 및 차단을 위해 설치한 스프링클러와 배연설비의 통합작동이 유동장의 온도 및 연기밀도 분포에 미치는 영향을 조사하기 위해 $20.0m\;\times\;4.0m\;\times\;3.0m$ 크기의 공간에 대해 전산유체역학 프로그램(FDS 4.0.3)의 화재모의실험을 수행하였다. 연기의 냉각 및 차단효과는 스프링클러와 배연설비의 통합작동이 단독작동 보다 더 우수한 것으로 확인되었고, 천장에 설치되는 스프링클러헤드는 천장 길이방향으로의 모서리 효과에 의해 작동 헤드수는 2개로 제한되었으며, 적정 헤드수를 초과한 헤드설치는 오히려 연기냉각 및 차단 효과를 저하시키는 것을 확인할 수 있었다. 본 연구에서는 2개의 헤드설치와 $3.0m^3/s$의 배연량인 경우 연기의 냉각 및 차단효과가 가장 좋았다. 헤드 작동 시 연기 하향끌림 현상이 발생하며, 화재크기의 증가로 연기발생 량이 배연 량 보다 큰 경우에는 연기 하향끌림 현상이 훨씬 더 크게 나타남을 확인할 수 있었다.

• Nuclear Engineering and Technology
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• 제48권5호
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• pp.1184-1191
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• 2016

This paper introduces the development of a transient monitoring system to detect the early stage of a transient, to identify the type of the transient scenario, and to inform an operator with the remaining time to turbine trip when there is no operator's relevant control. This study focused on the transients originating from a secondary system in nuclear power plants (NPPs), because the secondary system was recognized to be a more dominant factor to make unplanned turbine-generator trips which can ultimately result in reactor trips. In order to make the proposed methodology practical forward, all the transient scenarios registered in a simulator of a 1,000 MWe pressurized water reactor were archived in the transient pattern database. The transient patterns show plant behavior until turbine-generator trip when there is no operator's intervention. Meanwhile, the operating data periodically captured from a plant computer is compared with an individual transient pattern in the database and a highly matched section among the transient patterns enables isolation of the type of transient and prediction of the expected remaining time to trip. The transient pattern database consists of hundreds of variables, so it is difficult to speedily compare patterns and to draw a conclusion in a timely manner. The transient pattern database and the operating data are, therefore, converted into a smaller dimension using the principal component analysis (PCA). This paper describes the process of constructing the transient pattern database, dealing with principal components, and optimizing similarity measures.

• 한국군사과학기술학회지
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• 제24권3호
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• pp.328-338
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• 2021

A study on common modular design based on open standards to reduce the life cycle cost of ground weapon system is underway. Since the ground weapon system includes major mission equipment such as fire control system, it is essential to apply the concept of fault tolerance through automatic reconfiguration and blocking unspecified equipment through connectivity control. However, it is difficult to generalize due to the difference in operating characteristics for each system. In this paper, we propose a plug-and-play framework, which includes plug-and-play architecture and mechanism. The proposed method can be used in common by the application of each component as it is divided into a common service layer. In addition, the proposed connectivity control and autonomous reconfiguration method facilitates reflection of operating characteristics for each system. We constructed a verification environment that can simulate ground weapon systems and components, and verified that the proposed framework works through scenario-based functional tests.

• 한국해양공학회지
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• 제36권3호
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• pp.181-193
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• 2022

This study presents a mission management technique that is a key component of underwater docking system used to expand the operating range of autonomous underwater vehicle (AUV). We analyzed the docking scenario and AUV operating environment, defining the feasible initial area (FIA) level, event level, and global path (GP) command to improve the rate of docking success and AUV safety. Non-holonomic constraints, mounted sensor characteristic, AUV and mission state, and AUV behavior were considered. Using AUV and docking station, we conducted experiments on land and at sea. The first test was conducted on land to prevent loss and damage of the AUV and verify stability and interconnection with other algorithms; it performed well in normal and abnormal situations. Subsequently, we attempted to dock under the sea and verified its performance; it also worked well in a sea environment. In this study, we presented the mission management technique and showed its performance. We demonstrated AUV docking with this algorithm and verified that the rate of docking success was higher compared to those obtained in other studies.

• Architectural research
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• 제18권1호
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• pp.13-20
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• 2016

Smart Home has achieved remarkable developments over the past few decades. In the ICT(Information and Communications Technology) field, 'app ecosystem'-a collection of multiple devices such as mobile phones and tablets, software (operating system and development tools), companies (manufacturers, carriers, app-stores, etc.) and the process through which data is transferred/shared by a user from one device to another device or by the device itself-has come into wide use since the advent of the smart phone. Due to the synergy effect of the 'app ecosystem', it has been applied to various fields such as televisions and automobile industries. As a result, both the Smart TV and connected vehicle have developed their own ecosystem. Although much research has been conducted on these two ecosystems, there is a lack of research regarding 'App Ecosystem based Smart Home' (AESH). This research focuses on the building scenarios based on 'Tracking, Analyzing, Imaging, Deciding, and Acting (T.A.I.D.A), a future prediction method process. Rather than taking an approach from the perspective of providing and applying advanced technology for research on building future scenarios, this paper focuses on research from the perspective of architectural planning. As a result, two future scenarios of AESH are suggested.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2004년도 ICCAS
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• pp.1187-1190
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• 2004

This paper presents a traveler guidance system that offers 3D street information such as road types, signal light systems, street trees, buildings, etc. We consider 5x4 road system of Gangnam(in Seoul, Korea) as a test area and reflect the traveler's car-driving situation. A web server is constructed to serve traveler's driving path by switching 3D animation scenes automatically. To do batch processing of geometric data for the 3D graphical streets construction, we have extracted major street information from present GIS database and created new GIS file formats (SMF files), which contain data sessions for links, nodes, and facilities. With these files, we can render 3D navigation scenes. A number of vector calculations were performed for the geometrical consistence and texture-mapping method was used for the realistic scene generation. Finally, we have verified the effectiveness of the service by operating a test scenario. We have checked whether traveler's 2D path and 3D navigation are exactly reported after setting specific departure and destination. This system offers us well awareness of streets and takes useful role of traveler guidance.

• 시스템엔지니어링학술지
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• 제14권1호
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• pp.83-88
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• 2018

Engineering is a sector with more than three times the industrial effectiveness of manufacturing. In the domestic engineering life cycle, the Operations & Maintenance (O&M) phase is a relatively high level of technology. Based on accumulated knowledge of O&M phase, it is necessary to advance operating technology and expand overseas O&M market expenditure. This study is the early stage of knowledge-based power plant O&M service framework reference model. In this study, we propose a conceptual model of architecture framework for power plant O&M. We survey the architecture framework and reference model and propose conceptual model of architecture framework for power plant O&M. The conceptual model of architecture framework for power plant O&M consists of stakeholder, O&M scenario, O&M technology. In particular, the O&M technology is defined as the fourth industrial revolution intelligence information technology. We defined a meta model from the conceptual model to define the power plant O&M architecture framework. In the future, we intend to development an architecture framework from the conceptual model and meta model.

• 한국조리학회:학술대회논문집
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• 한국조리학회 2004년도 IFMCS 2004 제1회 외식ㆍ조리ㆍ호텔 식음료 국제 학술대회
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• pp.41-54
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• 2004

미국의 레스토랑 업계는 타 국가들의 최고 경영자들의 모델일 수 있습니다. 미국의 레스토랑 업계는 지난 50여년 동안 주로 지역의 소규모로 운영하는 회사에서 거대 회사로 점유된 업계로 발전했고 또한 대규모, 국제적 기업으로 변모한 성숙한 산업으로 발전했습니다. 국가들이 경제 성장을 거듭하고 각 지역 소비자들이 윤택해 지면서 이러한 시나리오는 전세계적으로 적용 될 수 있다고 예상하고 있습니다. 허약한 회사는 시장의 전략적 핵심을 이해 하지 못해 곤란을 겪게 되는 반면 미래 환경에 기회를 이용하며 우수한 전략을 개발 할 수 있는 레스토랑 회사는 끈임 없이 성공할 것입니다.

• 한국정밀공학회지
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• 제22권3호
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• pp.68-77
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• 2005

The set-up of an injection molding process is a ye complicated and time-consuming job because it is required to well determine a lot of variables closely related to products. Thus, the productivity of the set-up process mainly depends on operators' expertise and know-how. To solve the problem mentioned before, this research constructs a support system which helps operators determining the condition of the injection molding easily and systematically. The construction of the support system consists of the following four steps: 1) to determine the control variables which affect the target defect types, 2) to design and implement UI(user interface) using a scenario of set-up process, 3) to design and implement the search algorithms for the initial and optima] condition, and 4) to construct the embedded system which integrates the support system with the operating system of a plastic injection molding machine. The test experiments of some typical products are performed using the embedded system to verify the validity of the support system.