Alloy 600 노즐관통부의 이종금속용접 잔류응력에 따른 응력부식균열 거동 분석

김성우,김홍표,김동진,정재욱,장윤석,Kim, Sung-Woo,Kim, Hong-Pyo,Kim, Dong-Jin,Jeong, Jae-Uk,Chang, Yoon-Suk 한국압력기기공학회 2010 한국압력기기공학회 논문집 Vol.6 No.2

This work is concerned with the analysis of stress corrosion cracking(SCC) behavior of Alloy 600 nozzle penetration mock-up according to a residual stress induced by a dissimilar metal welding(DMW) in a nuclear reactor pressure vessel. The effects of the dimension and materials of the nozzle penetration on the deformation and the residual stress induced by DMW were investigated using a finite element analysis(FEA). The inner diameter(ID) change of the nozzle by DMW and its dependance on the design variables, calculated by FEA, were well consistent with those measured from the mock-up. Accelerated SCC tests were performed for three mock-ups with different wall thicknesses in a highly acidic solution to investigate mainly the effect of the residual stress on the SCC behavior of Alloy 600 nozzle. From a destructive examination of the mock-up after the tests, the SCC behavior of the nozzle was fairly related with the residual stress induced by DMW : axial cracks were found in the ID surface of the nozzle within the J-weld region where the highest tensile hoop stress was predicted by FEA, while circumferential cracks were observed beyond both J-weld root and toe where the highest tensile axial stress was expected.

BLE 상의 IPv6 기반의 실시간 모니터링 시스템

김성우,Kim, Seong-Woo 한국정보통신학회 2017 한국정보통신학회논문지 Vol.21 No.2

근래 제한된 자원과 이기종 통신 장치를 가진 사물들이 인터넷을 통해 서로 연결되어 정보를 주고받는 사물인터넷 기술이 각광받고 있다. 본 논문에서는 블루투스 4.2 기술인 Bluetooth Low Energy(BLE) 상에서 IPv6를 사용하여 센서 등을 실시간으로 모니터링할 수 있는 시스템을 제안한다. 본 시스템은 발행-구독 방식의 사물인터넷 프로토콜인 Message Queuing Telemetry Transport(MQTT)를 이용하여 별도의 데이터 변환이나 프록시가 필요 없이 데이터를 전송할 수 있다. 본 시스템과 연동된 웹 클라이언트에서는 BLE 장치가 감지한 센서 데이터는 MQTT 브로커로 중개된 후에 HTTP 및 웹소켓 프로토콜을 통해 웹 클라이언트로 전달되므로 센서 데이터를 실시간으로 모니터링할 수 있다. 본 논문에서는 테스트 플랫폼을 구현하여 네트워크 성능을 검증하고 본 시스템의 유효성을 확인하였다. 따라서 본 시스템을 적용하면 개발 비용을 줄이고 이기종 장치들로 사물인터넷 망을 쉽게 구성할 수 있다. Recently it has drawn much attention on the technologies about Internet of Things (IoT) which connects objects with constrained resource and heterogenous communication module in order to communicate information via internet. We propose a real-time sensor monitoring system based on IPv6 over Bluetooth Low Energy (BLE), which is included in Bluetooth 4.2 Specification. Since this system uses a publish-subsribe based IoT protocol, so called Message Queueing Telemetry Transport (MQTT), neither transforming network data nor any proxy server is needed in order to transmit data. Through the web client connected to this system, you can monitor sensor data sent by BLE device in real-time, intermediated via MQTT broker and then delivered to the client via HTTP and websocket protocol. In this paper we evaluated network capacity and availability of the implemented test platform. Thus by using this system it is possible to make development cost low and to construct IoT network with heterogenous devices easily.

흡수 마코프체인을 활용한 함정 근접무기체계 효과성 분석

김성우,윤봉규,Kim, Seong-Woo,Yoon, Bong-Kyoo 한국군사과학기술학회 2014 한국군사과학기술학회지 Vol.17 No.6

Since the technology of anti-ship missiles has advanced rapidly, defending battleships from the threat of anti-ship missiles is a crucial factor for the survival of warships. In this paper, we analyze the performance of an anti-ship missile defense system whose name is Close-In-Weapon-System. We show the survival probability of a warship equipped with the Close-In-Weapon-System as the number of anti-ship missiles attacking the warship varies. Because of the complex and dynamic operational characteristics surrounding the Close-In-Weapon-System such as speed of missiles, different range of an individual weapon in the weapon system, and the continuous change of the kill probability of the missiles corresponding to the distance of missiles from ships, few work has been done for the performance of Close-In-Weapon-System. We present a model to incorporate all the dynamic characteristics of the system using absorbing Markov Chain. With our results, we expect commanders of warships equipped with Close-In-Weapon-System to be provided with more helpful information on how to deal with the anti-ship missiles.

A Survey on the Health Status of Population with Disability in Goyang City

김성우,Gwang Bok Park,Hyoung Seop Kim,Jung Bin Shin,김종문,Myoung Sik Bae 대한재활의학회 2011 Annals of Rehabilitation Medicine Vol.35 No.1

Objective To improve the quality of life of the disabled population by decreasing the incidence of complications and chronic diseases and improving self-care abilities according to individual diseases through health status evaluation and basic survey. Method The basic clinical information of 1,378 regional severely-disabled patients were collected along with information regarding functional level, activities of daily living, nutritional status, and management of complications which were distinguished into 3 stages (good, moderate, poor), which were correlated into scores (1-3 points) that were used to assess a collaborative score (5-15 points) that represented their health status. Health behavior and blood tests were also done. Results Health status were evaluated based on sex, grade of disability, age, frequency of exercise and type of disability, which revealed that female sex, brain disorder, 1st grade disability, total lack of exercise, old age disabled patients were relatively poor in terms of health status. Conclusion Health status of the severely-disabled showed differences according to sex, age, grade of disability, type of disability, and frequency of exercise, and health programs designed to screen and follow up the severely-disabled person with poor health status as well as manage their accompanying diseases and complications are needed.

UPnP 기반 지능형 로봇 제어 시스템 구현

김성우,박유현,권순각,Kim, Seong-Woo,Park, Yoo-Hyun,Kwon, Soon-Kak 한국정보통신학회 2012 한국정보통신학회논문지 Vol.16 No.10

유비쿼터스 홈 서비스에 대한 기대가 높아지면서 지능형 로봇에 대해 폭넓은 관심이 요구되고 있다. 이러한 로봇은 원격 서버와 연동할 수 있는 미들웨어를 통해 다양한 서비스를 제공할 수 있다. 본 논문에서는 지능형 로봇의 원격 제어를 위한 UPnP 구조 기반의 오픈 소스 소프트웨어 프레임워크를 개발하였다. 홈 네트워크에 많이 사용되는 UPnP 구조는 명령 제어, 이벤트 전달, 웹 서비스 등 다양한 통신 방식을 제공한다. 본 논문에서는 2 종류의 실제 플랫폼에 탑재되어 성공적으로 구현된 결과를 보여준다. With the increased demand of ubiquitous home services, intelligent robots have wide attentions. This kind of robots offer various services through middleware components which can connect with remote servers. In this paper we present an UPnP(Universal Plug and Play) based open-source software framework which makes control the robots remotely. This UPnP architecture for home networking can provide various communication methodologies like command control, eventing, presentation with web services and so on. This paper shows successful implementation results on two real platforms.

A New Parallel Method for Narrowband Active Noise Control

김성우,박영철,서영수,윤대희,Kim, Seong-Woo,Park, Young-Cheol,Seo, Young-Soo,Youn, Dae Hee The Acoustical Society of Korea 2014 韓國音響學會誌 Vol.33 No.6

많은 실제 능동 소음 제어 분야에서 주요 소음은 다수의 인접한 배음으로 구성된다. 또한 협대역 능동 소음 제어 시스템은 정현파 세트나 혹은 합으로 구성된 기준 신호에 의해 동작하는 적응 필터들로 구성된다. 본 논문은 직접형, 병렬 형, 간소화한 병렬 형의 능동 소음 제어 시스템이 기본 주파수와 인접한 정현파의 주파수 간격에 영향을 받음을 보여주고 이를 분석한다. 또한 본 논문은 기준 주파수에 독립적인 새로운 간소화한 병렬 형 협대역 능동 소음 제어 시스템을 제안한다. 본 논문에서의 제시한 분석을 증명하고 새로운 협대역 능동 소음 제어 시스템을 기존 협대역 능동 소음 제어 시스템과 비교하기 위해 컴퓨터 시뮬레이션을 수행한다. In many practical active noise control applications, the primary noise contains multiple closely-spaced harmonics. A narrowband ANC system consists of adaptive filters excited by a composite reference signal, which is the set or sum of sinusoids. This paper analyzes and shows that the convergence speeds of the direct form, parallel form, and simplified parallel form narrowband ANC systems are affected by the fundamental frequency and frequency separation between two adjacent sinusoids in the reference signal. This paper also proposes the new simplified parallel form narrowband ANC system whose convergence speed is independent on the frequency of the reference signal. Computer simulations are conducted to verify the analysis presented in the paper and to compare the proposed narrowband ANC system with the conventional narrowband ANC system.

연구발표논문초록 : 화학공정 ( 2 ) ; 원통형 금형으로된 폴리우레탄 반응사출 공정에서의 충전과 경화 현상에 대한 수치모사

김성우,이기준 ( Seong Woo Kim,Ki Jun Lee ) 한국화학공학회 1985 추계총회초록집 Vol.- No.-

한국형 기동헬기 임무탑재장비체계 설계 및 입증

김성우,이병화,유연운,이종훈,임종봉,Kim, Sung-Woo,Lee, Byoung-Hwa,Yu, Yeon-Woon,Lee, Jong-Hoon,Yim, Jong-Bong 한국군사과학기술학회 2011 한국군사과학기술학회지 Vol.14 No.3

Mission Equipment Package(MEP) system is a collection of avionic components that are integrated to perform the mission of the Korean Utility Helicopter(KUH). MEP system development is classified mission-critical embedded system but KUH MEP system developed including flight-critical data implementation. It is important to establish the good development and verification process for the successful system development. This paper describe the development and verification process in each phase for the KUH MEP system. MEP system design is verified through the qualification test, system failure test and compatibility test in System Integration Laboratory(SIL).

한국형 가동헬기 임무탑재장비 요구항법성능 구현

김성우,이병화,오우섭,Kim, Sung-Woo,Lee, Byoung-Hwa,Oh, Woo-Seop 한국군사과학기술학회 2011 한국군사과학기술학회지 Vol.14 No.5

A number of navigation improvements are envisaged : Differential GPS - WAAS, LAAS, and Performance Based Navigation. The GPS receiver verifies the integrity(usability) of the signals received from the GPS constellation through a process called receiver autonomous integrity monitoring(RAIM) to determine if a satellite is providing corrupted information. This paper describe the RAIM function and Performance-Based Navigation implementation of Mission Equipment Package(MEP) for Korean Utility Helicopter.

동서양 건축에서의 공간과 시간

김성우,Kim, Sung-woo 한국건축역사학회 2004 건축역사연구 Vol.13 No.3

The tradition of architecture in the East and the West are different in many ways. One of the basic cause of such difference, however, is the different ways of perception of space and time. This paper aims to identify the attitude of perception of space and time in the cultures of the East and the West, and its influence on architecture. Degrees of importance placed on either space or time, as well as the modes of perception of space and time are discussed in relation to architecture. Basically, the architecture of the West seems to be more spatially oriented than the East, and this have much to do with the fact that the tradition of Western architecture is visually oriented. On the other hand, East Asian architecture have been more conscious on bodily feeling and its movement in architecture. Spatial units of traditional Eastern architecture, are arranged in such a way in which man can experience the change of space that is supposed to be organized to form a sequential message. Thus, in the East, temporal dimension is more deliberately included in the course of architectural experience compared to the cases of the West. Although it is not easy to attempt any kind of value judgment on such aspects, it is necessary to understand how the different perception of space and time influenced architectural outcome, especially when one wants to understand the cultural cause that have made the architectures of the East and the West very different. Such understanding is particularly important in East Asia where their future of architecture depends much on how they harmonize the Eastern and Western background which are already built up as two cultural structure in their consciousness to be able to create more desirable architecture for themselves.