• Title/Summary/Keyword: portable system

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휴대 인터넷을 위한 OFDMA 시스템에서 무선채널 상태에 따른 서브채널할당 (Sub-channel Assignments by Link Status on OFDMA Systems for WiBro Service)

  • 임석구
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2005년도 추계 종합학술대회 논문집
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    • pp.596-600
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    • 2005
  • In High-speed Portable Internet system to improve performance of whole system, adaptive modulation and coding technology is used, this technology changes modulation and encoding techniques depending on wireless channel environment. Modulation technology that is used in High-speed Portable Internet system is BPSK, QPSK, 16QAMs and 64QAMs. If terminal is distant from base station transceiver system, BPSK or QPSK technology Is used and 16QAMs or 64QAM technology is used if is near in the base station transceiver system. In this paper, number of sub-channel in each modulation technology minimized total transmitting number of PDU is analyzed for efficient radio resources usage. For this, simulation is conducted and the results are presented at High-speed Portable Internet system environments.

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근적외 분광법을 응용한 휴대용 벌꿀 품질 평가 장치 개발 (Development of a Portable Quality Evaluation System for Bee-honeys by Using Near Infrared Spectroscopy)

  • 최창현;김종훈;권기현;김용주
    • 한국식품저장유통학회지
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    • 제18권2호
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    • pp.156-164
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    • 2011
  • This study was conducted to develop a portable quality evaluation system of bee-honey by near infrared spectroscopic technique. Two kinds of bee-honeys from acacia and polyflower sources were tested in this study. The system consists of power supply, tungsten-halogen lamp, detector, and optical fiber probe. Performance of the system was analyzed by comparing the prediction accuracy of the laboratory spectrophotometer. Total of 346 spectra was divided into a calibration set and a prediction set. The PLS (Partial Least Squares) models were developed to predict the quality parameters of bee-honeys. Reflectance spectra, moisture contents, ash, invert sugar, sucrose, F/G ratio, HMF(hydroxy methyl furfural), and $C^{12}/C^{13}$ ratio of honeys were measured. The PLS models of the laboratory spectrophotometer showed good relationships between predicted and measured quality parameters of honeys in the wavelength range of 1.100~2.200 nm. The PLS analysis of the portable quality evaluation system showed good relationships between predicted and measured quality parameters of honeys in the wavelength range of 1.100~1.300 nm and 1.400~1.700 nm. The results showed the feasibility of the portable quality evaluation system to determine the quality parameters of bee-honey in the field during harvesting.

이동식 미디어 플레이어를 이용한 도킹 스테이션 설계 (Docking Station Implementation using Portable Media Player)

  • 정은숙;류광렬
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2011년도 추계학술대회
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    • pp.938-941
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    • 2011
  • 본 연구에서 디지털 방송 수신 및 저장을 위하여 이동식 멀티미디어 플레이어를 이용하여 도킹스테이션을 설계하였다. 디지털 방송 콘텐츠 수신 및 저장은 셋탑박스를 이용하며 이동식 미디어 플레이어와 탈부착 기능을 부가하였고, 이동식 미디어플레이어의 OS는 안드로이드를 사용하였다. 구현결과 이 시스템은 디지털방송, 지상파, 위성방송, DMB 등의 수신이 가능하며 비디오 영상은 실시간으로 저장된다.

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무 설치 프로그램에서의 사용자 행위 아티팩트 분석 (A Study On Artifacts Analysis In Portable Software)

  • 허태영;손태식
    • Journal of Platform Technology
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    • 제11권2호
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    • pp.39-53
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    • 2023
  • 무 설치 프로그램(이하 '포터블 프로그램'이라 한다.)은 일반적 소프트웨어와는 다르게 설치과정 없이 사용할 수 있는 프로그램이다. 별도의 설치 과정이 없기 때문에 포터블 프로그램은 높은 이동성을 가지며 다양하게 활용된다. 예를 들어, 다수의 PC의 초기 설정이 필요할 때 하나의 USB 드라이브에 다양한 포터블 프로그램을 저장하여 초기설정을 할 수 있다. 또는 PC에 문제가 발생하여 정상적인 부팅이 어려울 때 USB 드라이브에 Windows PE를 구성하고 저장된 포터블 프로그램으로 PC 복구에 사용될 수 있다. 그리고 포터블 프로그램은 레지스트리 값 변경 등 PC 설정에 직접적인 영향을 끼치지 않으며 흔적을 남기지 않는다. 이는 다시 말해, 포터블 프로그램이 높은 보안성을 가진다는 것을 의미한다. 포터블 프로그램을 사용 후 삭제하면 일반적인 방식으로의 행위분석에 어려움이 존재한다. 만약 사용자가 악성 행위에 포터블 프로그램을 사용하였다면 일반적인 방식으로의 분석으로는 증거 수집에 한계가 따른다. 따라서 포터블 프로그램은 일반적인 설치 소프트웨어와는 다른 새로운 방식의 행위분석이 이루어져야 한다. 본 논문에서는 가상머신 상에서 Windows 10 운영체제를 설치한 후 Opera, Notepad++의 포터블 프로그램으로 시나리오를 진행한다. 그리고 이를 운영체제의 파일분석, 메모리 포렌식 등의 다양한 방법으로 분석하여, 프로그램 실행시간, 횟수 등의 정보를 수집하고, 사용자의 구체적 행위분석을 실시한다.

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자동 고장 판별 및 거리 측정 기능을 갖는 휴대용 케이블 고장 검출 장치 개발 (Development of Portable Cable Fault Detection System with Automatic Fault Distinction and Distance Measurement)

  • 김재진;전정채
    • 전기학회논문지
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    • 제65권10호
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    • pp.1774-1779
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    • 2016
  • This paper proposes a portable cable fault detection system with automatic fault distinction and distance measurement using time-frequency correlation and reference signal elimination method and automatic fault classification algorithm in order to have more accurate fault determination and location detection than conventional time domain refelectometry (TDR) system despite increased signal attenuation due to the long distance to cable fault location. The performance of the developed system method was validated via an experiment in the test field constructed for the standardized performance test of power cable fault location equipments. The performance evaluation showed that accuracy of the developed system is less than 1.34%. Also, an error of automatic fault type and location by detection of phase and peak value through elimination of the reference signal and normalization of correlation coefficient and automatic fault classification algorithm not occurred.

휴대 인터넷 시스템에서의 패킷 스케줄링 알고리즘 연구 (A Packet Scheduling Algorithm for High-speed Portable Internet System)

  • 최성훈
    • 산업경영시스템학회지
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    • 제30권1호
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    • pp.59-65
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    • 2007
  • HPI (High-speed Portable Internet) system which provides high speed internet services is going to be commercialized soon. Since HPI provides simultaneously four different service types such as UGS (Unsolicited Grant Service), rtPS (real time Polling Service), nrtPS(non-real time Polling Service), and BE (Best Effort) under different QoS (Quality of Service) requirements and limited wireless channel resources, efficient packet scheduling mechanisms are necessary to increase the utilization of channels as well as to satisfy the various QoS requirements. This study regards the traffic data to be served as time series and proposes a new packet scheduling algorithm based on the nonparametric statistical test. The performance of the newly proposed algorithm is evaluated through the simulation analysis using a simulator that can evaluate the performance of packet scheduling mechanisms under various values of system parameters and measures such as packet delay time, data transmission rate, number of loss packets, and channel utilization.

An alternative portable dynamic positioning system on a barge in short-crested waves using the fuzzy control

  • Fang, Ming-Chung;Lee, Zi-Yi
    • Ocean Systems Engineering
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    • 제5권3호
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    • pp.199-220
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    • 2015
  • The paper described the nonlinear dynamic motion behavior of a barge equipped with the portable outboard Dynamic Positioning(DP) control system in short-crested waves. The DP system based on the fuzzy theory is applied to control the thrusters to optimally adjust the ship position and heading in waves. In addition to the short-crested waves, the current, wind and nonlinear drifting force are also included in the calculations. The time domain simulations for the six degrees of freedom motions of the barge with the DP system are solved by the $4^{th}$ order Runge-Kutta method. The results show that the position and heading deviations are limited within acceptable ranges based on the present control method. When the dynamic positioning missions are needed, the technique of the alternative portable DP system developed here can serve as a practical tool to assist those ships without equipping with the DP facility.