• 전기학회논문지
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• 제57권3호
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• pp.488-493
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• 2008

This paper represents a dual-mode type transmission technique for a high reliable narrow-band power line communication(PLC) modem, and its design and implementation of a system-on-chip(SoC). The proposed transmission technique is based on a Chirp modulation for the purpose of overcoming time variations of power line channel environments in the narrow-bandwidth of the frequency range of 95-145.5 kHz. The designed modem is fabricated utilizing a mixed 0.18 ${\mu}m$ CMOS technology. Especially, according to the power line channel environments the data transmission rate can be selectively changed into 2.5 kbps and 480 bps. The total hardware complexity of the implemented chip is about 50,000 gates, the power consumption is about 26mW, and the operating frequency is up to 5.12 MHz.

• 한국군사과학기술학회지
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• 제7권4호
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• pp.133-137
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• 2004

A simplified test rig to simulate high-altitude environments was designed by analyzing the AEDC (Arnolds Engineering Development Center) report regarding simulated altitude testing. The test rig consists of a vacuum chamber, a supersonic nozzle connected to a cold-gas supplier and a diffuser. The preliminary tests were conducted to validate the AEDC design concepts. The test results showed that sub-atmospheric pressure(1.0psia) environments were realized inside the vacuum chamber and the design concepts were confirmed.

• 한국전자통신학회논문지
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• 제7권5호
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• pp.975-981
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• 2012

본 논문에서는 다중 경로 채널 환경에서 터보 코드를 사용하여 광대역 CDMA 시스템의 수신 신호를 고려하고, 시스템의 성능을 분석합니다. Rayleigh 페이딩 채널 환경에서 터보 코드와 함께 레이크 수신기를 통해 수신된 신호를 전달하여 레이크 수신기의 가지 수에 따라 가변 시스템 대역폭에 대한 성능을 분석한다. 광대역 CDMA 시스템에서 수신기의 디자인을 위해서는 디코딩 및 레이크 수신기의 가지 수를 효율적인 매개 변수를 제시했습니다.

• 한국컴퓨터산업학회논문지
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• 제2권8호
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• pp.1099-1108
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• 2001

본 논문에서는 웹 기반의 분산 소프트웨어 개발 환경에서 원시 코드 중심의 버전뿐만 아니라 원시 코드 이전 단계의 UML(Unified Modeling Language) 기반의 소프트웨어 개발 환경에서 발생하는 다양한 설계 객체들을 일정한 형태로 구축하여 효율적으로 관리하는 방법론을 제시하였다. 또한, 웹을 기반으로 한 분산 소프트웨어 개발 과정에서 발생하는 버전들을 일관성 있게 관리하기 위해 버전 규칙에 기초한 웹 기반의 규칙 버전 관리 모델을 설계하였다.

• 조명전기설비학회논문지
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• 제20권10호
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• pp.158-163
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• 2006

In this paper, we considered the received signal of the wideband CDMA systems using turbo code in the multipath channel environments, and analyze the performance of the system. This study is to analyze the performance for the variable system bandwidth according to the number of branches of rake receiver by passing the received signal through a rake receiver with a turbo code in Rayleigh fading channel environments. For the design of receiver in wideband CDMA systems, we presented the efficient parameters for the number of iterative decoding and the number of branches of rake receiver.

• 제어로봇시스템학회논문지
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• 제10권4호
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• pp.377-384
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• 2004

Nowadays, control systems consist of smart sensors, smart actuators, and controllers connected via fieldbus. Some devices such as motors in plant environments generate high degrees of EMI or noise. This noise may cause communication errors and make the successful transmission of data longer. Therefore, the noise condition has to be considered at the design of a reliable control system based on a network. This paper presents a scheduling method of task and message to guarantee the given end-to-end constraints under noise environments. A noise model with multi-sources of noise is used, and the analysis method of message's response time is presented when the noise model is applied to CAN (Controller Area Network). Two kinds of noise models are applied to an example system, and the effect to each control loop s end-to-end response time is analyzed. We believe that the proposed method help system designers design the control system guaranteeing its requirements under noise environment.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(3)
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• pp.169-172
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• 2000

Recently, the advent of World-Wide-Web(WWW) and the explosive popularity of the Internet gave birth to collaborative applications which were enabled by computers and networks as their primary media. And the progress of 3D computer graphics enabled collaborative application with 3D virtual environments or distributed virtual environments. In this paper, we explain our implementation of Share collaboration engine and Virtual Architectural Engineering 2000 (VAE2000) system which is our pilot application implemented with Share collaboration engine. And we explain problems presented by our experiments with VAE2000 system. For those problems, we design our new middle-ware system, SHINE(SHared INternet Environment). The SHINE proposes new concepts and approaches for collaboration with 3D objects in a virtual world.

• 한국통신학회논문지
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• 제23권9A호
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• pp.2258-2270
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• 1998

Recently, the distributed processing environments provide various open multimedia serivces through telecommunication network and have been developing into information networking structure based on object oriented concepts and distributed systems which can apply new services with a few changes the existing networks. This paper proposes the object group model which is the collection of objects and can functionally and efficiently manage the individual object. this paper presents the analysis of the requirement and the function specifications to propose the object group model, and depicts the functional structure in details using its analysis. The goal of this paper is to decrease the complexity of the object's management and to voercome the limitations of among the components of object group for management and service functions based on our proposed the object group model and show interaction procedures to eTD (event tracing diagram)s and finally we design the object group model by TINA-ODL.

• 한국CDE학회논문집
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• 제20권1호
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• pp.55-64
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• 2015

The earthquake is a natural disaster causing loss of life or property damage and happens more often in Korea recently. Moreover, considering the increase of massive buildings, it is required to predict and visualize the information of the vibration in a building. In this paper, we developed a prototype framework to visualize the displacement information in the AR environments. In order to avoid the irregular halts of the scene and the unnatural distortion of the object, this framework uses the synchronization method at the scene update time and the interpolation of the sensor data for the displacement of vertices. In addition, we studied displacement estimation methods with the acceleration data to extend this framework to the system with accelerators.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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• pp.189-192
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• 2005

In recent years, many research works have been carried out in order to obtain a more controlled durability and long-term performance of concrete structures in chloride containing environments. In particular, the development of new procedures for probability-based durability analysis/design has proved to be very valuable. In this paper, the equation used for modelling of the chloride penetration was based on Fick's Second Law of Diffusion in combination with a time dependent diffusion coefficient. The probability analysis of the durability performance was performed by use of a Monte Carlo Simulation. The procedure was applied to an example based on limited data gathered in this country. The influences of each parameter on the durability of concrete structures are studied and some comments for durability design are given. The new procedure may be very useful in designing concrete structures in chloride containing environments.