• Proceedings of the KIEE Conference
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• 2005.05a
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• pp.155-157
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• 2005

The Electrical Test Bed(ETB) integrates the test environment, required for acceptance tests of system level, prior to FM testing. The ETB will be used for the validation of system-level functions and interface between each subsystem. The FTB supports early functional and limited performance checkout of electrical subsystems. Therefore, it provides the environment for the verification of the Flight Software including AOCS, EPS, and TC&R simulators. These ETB will be composed of engineering version of spacecraft BUS, which are laid on the laboratory table.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1998.11a
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• pp.313-316
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• 1998

통신처리시스템(Communication Processing System)은 전화망과 ISDN 가입자들에게 전국 규모의 PC 통신 및 인터넷 액세스를 가능하게 하기 위한 망정합 장치이며, 동시에 통신처리 서비스를 제공하는 시스템이다. 본 논문에서 기술하고자 하는 통신처리시스템 전화망 정합장치는 120 채널 규모의 용량으로 설계되었으며, 전화망과는 텐덤교환기 레벌과 4개의 El 트렁크 접속방식으로 연결되며 R2 MFC 방식을 사용한다. 접속된 가입자 회선은 ITU-T V.90 규격에 따르는 모뎀풀을 사용하여 정합되며 이 정보들은 역다중화된 후 서비스된다. 이 정보들은 데이터 처리 블록, 입출력 기능 블록, 사용자 명령어 처리 블록, 서비스처리 블록에 의해 복수의 서비스 제공자 망에 접속된다. 본 논문에서는 이러한 통신처리시스템에 연결되는 전화망 가입자들에게 효과적으로 데이터 통신 서비스를 제공하기 위한 전화망 정합장치(TNAS; Telephony Network Access Subsystem)의 기능과 구조, 설계 및 구현 내용에 대해 기술한다.

• Asia pacific journal of information systems
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• v.3 no.2
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• pp.117-144
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• 1993

MIS researches involve, in particular, the problems of developing appropriate IS for given MIS environments and lay emphasis on identifying prominant IS characteristics pertaining to the system in issue. This study deals with the IS characteristics for the management task of "planning". It investigates empirically the impacts of IS characteristics, under a set of proposed hypotheses, with particular respect to users' information satisfaction and performance in carrying out the task of planning. Futhermore, it examines whether the IS characteristics have different effects depending on the planning modes on the part of IS users. Based on a group of hypotheses accepted, the IS characteristics for planning decision making are not only proposed according to planning modes: preactive, reactive and proactive, but also classified into six subsystem categories: input, process, ouput, storage, interface and communication. Finally, the implications of the findings are discussed.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.1
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• pp.13-20
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• 2008

Sensor network consists of a large number of sensor node distributed in the environment being sensed and controlled. The resource-constrained sensor nodes tend to have various and heterogeneous architecture. Thus, it is important to make its software environment platform-independent and reprogrammable. In this paper, we present BeeVM, a Java operating system designed for sensor networks. BeeVM offers a platform-independent Java programming environment with its efficiently executable file format and a set of class APIs for basic operating functions, sensing and wireless networking. BeeVM's high-level native interface and layered network subsystem allow complex program for sensor network to be short and readable. Our platform has been ported on two currently popular hardware platforms and we show its effectiveness through the evaluation of a simple application.

• Information and Communications Magazine
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• v.22 no.5
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• pp.130-140
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• 2005

3G 이동통신 시스템 표준화 단체인 3GPP ($3^{rd}$ Generation Partnership Project)와 3GPP2 ($3^{rd}$ Generation Partnership Project 2)는 이동통신망에서의 무선 IP 멀티미디어 서비스 확산을 위하여 유선 인터넷의 핵심 응용 서비스인 실시간 서비스를 도입하기 위한 표준화 작업을 진행하고 있다. 그리고, 현재 개발 중인 HSDPA (High Speed Downlink Packet Access)와 IMS (IP Multimedia CN Subsystem)는 궁극적으로 All IP 기반 광대역 멀티미디어 서비스 제공을 추구하고 있으며 Parlay API(Application Programming Interface)를 이용한 다양한 $3^{rd}$ party 응용서비스 제공 환경을 제공할 수 있을 것이다. 이에 본 고에서는 HSDPA 및 IMS를 포괄하는 All IP관련 표준화 현황을 조사하고 나아가 IMS와 HSDPA 기반 서비스 진화에 대한 고찰을 통해 향후 이동통신 서비스의 개발 방향을 예측해 보고자한다.

• Proceedings of the Korean Information Science Society Conference
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• 1999.10c
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• pp.694-696
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• 1999

최근에는 Non-PC 디바이스들을 위한 Embedded OS들이 PCS, PDA, 핸드헬드(Handheld) 컴퓨터, 터미널, 산업용 제어기 및 다른 소형 컴퓨터에서부터 인터넷 TV, 디지털 셋탑 박스, 웹폰, 인터넷 디바이스, 및 Mobile Computing 분야에 이르기까지 다양한 분야에서 그 요구가 급증하고 있다. 현재 이러한 응용들은 사용자의 응답시간이 빠른 표준 API(Application Programming Interface)의 사용을 필요로 한다. Window System의 Application을 개발하기 위해서는 보통 Win32 API를 사용한다. 그런, Win32 API에서 제공하는 자료형과 관련 함수들이 크기가 크고 속도가 느려서 소형의 적은 메모리와 빠른 속도를 필요로 하는 PCS 단말기에는 적합하지가 않다. 따라서 기존의 API의 기능을 충실히 수행하면서 PCS에 최적화된 API에 대한 연구가 필요하다. 본 논문에서는 PCS 정보단말기용 소형 운영체제에 적합한 API를 GWES(Graphics, Windowing, and Events Subsystem) 모델을 기반으로 설계하였으며 사용자 응답시간 지연을 해결하기 위해서는 Event 처리를 최소화하는 다중 메시지 처리 방식을 개발하였다.

• Journal of Engineering Education Research
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• v.13 no.2
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• pp.7-11
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• 2010

As the development of the computer and communication technologies, the ubiquitous society can be realized to the world early in the future. Thus, the localization system in Wireless Personal Area Network (WPAN) is required for many users of ubiquitous society to provide the ubiquitous computing based applications in respective of anytime and anywhere. In this paper, we propose the distance measurement scheme that is based on the distance measurement using RSSI (Received Signal Strength Indicator) of sensor module considering of two distance conditions for the localization system using Zigbee in WPAN. Also, the localization errors of the proposed scheme are analyzed in the three scenarios that the mobile module tracks in the in $6m{\times}6m$ scaled experimentation area. In addition to this, the monitoring subsystem is developed using GUI (Graphical User Interface) in order to monitor the location of the moving objects accurately and user-friendly.

• Proceedings of the KSR Conference
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• 2000.05a
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• pp.157-163
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• 2000

Testing evaluation is a part of process for design, production, evaluation, operation and abolition, and is the process of certifying system performance. The main purpose of testing evaluation is to reduce the risk factor under the determining process. Testing process has the three step such as design qualification, integration and validation test in factory, system integration and commissioning test. Design Qualification is to verify errors on the design process. Integration and validation test in factory is for the H/W and S/W of an equipment and is to verify interface of subsystem, communication protocol and main functions. System integration and commissioning test is a functional test to adjust successful installation of equipment. According to the testing process, briefly consideration for test item, test method and test contents about signalling system is carried out.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.1483-1487
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• 2006

In electric railway, image monitoring using high speed camera provides reliable, timely information of wear and geometry status, important in taking decisions for overhead contact wire maintenance. The contribution of this research is the development of a simple real-time monitoring system for use in measurement subsystem of contact wire and geometry of overhead contact wire in electric railway. The system has been consists of a high speed CMOS camera with resolution $1024{\times}1280$ pixels, line type laser source and PC-based image acquisition system with PCI Express slot. Vision acquisition software have been used in application programming interface for image acquisition, display, and storage with a frequency of sampling of 500 acquisitions per second.

• Information and Communications Magazine
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• v.6 no.1
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• pp.33-43
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• 1989

The subscriber & signal processing subystem of digital switching system TDX-1B has increased double in its capacity than TDX-1A, containing maximum 1024 subscribers per rack. It consists of subscriber interface devices, concentrating devices, signalling devices and controlling device in order to connect subscriber lines to switch network and supply subscriber signals for subscribers. This paper describes development procedures, principal functions of TDX-1B subscriber $ signal processing devices and the results.