• 제목/요약/키워드: Field Environment

검색결과 8,421건 처리시간 0.034초

야전 환경에서 기계구조물 표면처리 개선에 관한 실험적 연구 (Experimental Study on the Improvement of Surface Treatment of Mechanical Structures in Field Environment)

  • 김종화;현종훈;강석중
    • 한국군사과학기술학회지
    • /
    • 제24권2호
    • /
    • pp.197-203
    • /
    • 2021
  • Mechanical structures of military equipment have been mainly applied with black oxide coating due to the limitation of surface treatment thickness. However, the mechanical structures applied by the black oxide coating treatment is constantly being corroded by calcium chloride and humidity. Since this can cause serious problems in the operation of equipment, a review to improve surface treatment and corrosion resistance is required. Therefore, in this study, surface treatment methods that can enhance corrosion resistance were selected and corrosion resistance performance was verified through experiments describing harsh field conditions. Thus, applying a proven surface treatment method to future military equipment will prevent corrosion.

하절기 단일 수목의 열 환경 관측을 통한 서열완화 효과 해석 (Analysis of Passive Cooling Effect of the Tree by Field Observations in the Summer)

  • 최동호;이부용
    • 한국태양에너지학회 논문집
    • /
    • 제26권4호
    • /
    • pp.109-118
    • /
    • 2006
  • The tree is regarded as an sustainable architectural outdoor design element which reduce urban heat island effect by its solar shading and evapotranspiration. This study carried out field observations of measuring thermal environment of selected tree and its ambience to determine passive cooling effects. Results from the field observations are as below; Tree-shading effect to the thermal environment can not be properly evaluated by merely measuring air temperature differences between tree-shaded space and unshaded space for the maximum temperature difference is less than $1.5^{\circ}C$. The differences of longwave radiation and shortwave radiation between tree-shaded space and unshaded space are measured. Shortwave radiation is considered as a main thermal comfort determining factor for the difference of the shortwave radiation is much bigger than that of longwave radiation. By thermal infrared image analysis, the surface temperature of the tree under strong solar radiation is measured same as ambient air temperature. By which the evapotranspiration is considered to retard tree surface temperature raising effectively.

스마트 디바이스 기반의 농업환경관리 지원 서비스 (An Implementation of the management support service for agricultural environment using Smart Devices)

  • 강현중;이준욱;강성수
    • 스마트미디어저널
    • /
    • 제1권1호
    • /
    • pp.42-47
    • /
    • 2012
  • IT 기술의 발전은, 우리사회의 다양한 산업 분야에 적용 되어 우리의 삶을 보다 효율적이고 생산적으로 바꾸고 있다. 농업IT는 이러한 IT기술을 농업에 적용하여 작물의 생산량과 품질을 향상시키며, 소비자로 하여금 믿을 수 있는 생산, 유통 정보를 제공하는 기술이다. 오늘날 RFID/USN의 등장은 농산물과 연관된 생장, 환경 정보의 수집을 가능하게 하고 각종 환경센서 등을 통해 수집된 디지털 정보는 누적, 분석 등을 통해 이상기후 예측, 병해충 예찰, 작물의 생산성 향상 및 균일 생산 보장 등을 위해 활용될 수 있을 것으로 기대된다. 본 연구에서는 이러한 RFID/USN 기술을 기반으로 저전력 센서네트워크와 미들웨어, 생장관리 플랫폼을 통해 모바일 환경에서 재배 환경 정보의 지속적 모니터링 및 각종 생장 데이터의 수집 및 전송, 각종 작업정보의 교환이 가능하게 함으로써 재배자에게 보다 효율적으로 생장환경을 관리할 수 있는 시스템을 제안한다.

  • PDF

워터마크를 이용한 TV방송 광고모니터링 시스템 (Monitoring System for TV Advertisement Using Watermark)

  • 신동환;김경순;김종원;최종욱
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
    • /
    • pp.15-18
    • /
    • 2004
  • In this paper, it is implemented the monitoring system for TV advertisement using video watermark. The functions of an advertisement monitoring system are automatically monitoring for the time, length, and index of the on-air advertisement, saving the log data, and reporting the monitoring result. The performance of the video watermark used in this paper is tested for TV advertisement monitoring. This test includes LAB test and field test. LAB test is done in laboratory environment and field test in actually broadcasting environment. LAB test includes PSNR, distortion measure in image, and the watermark detection rate in the various attack environment such as AD/DA(analog to digital and digital to analog) conversion, noise addition, and MPEG compression The result of LAB test is good for the TV advertisement monitoring. KOBACO and SBS are participated in the field test. The watermark detection rate is 100% in both the real-time processing and the saved file processing. The average deviation of the watermark detection time is 0.2 second, which is good because the permissible average error is 0.5 second.

  • PDF

문어흘림낚시용 친환경 봇돌의 색 효과 (Color effect of the environment-friendly sinker for octopus drift-line)

  • 안영일
    • 수산해양기술연구
    • /
    • 제45권3호
    • /
    • pp.144-150
    • /
    • 2009
  • The choice behavior of the octopus in response to the environment-friendly colored sinker for octopus driftline and the sinker's fishing effect were studied under experimental conditions in the water tank and the field. The colors of the sinkers used for the experiment are white, black, yellow and green. Artificial baits are attached to the sinkers in order to attract the octopuses in the experiment. In the water tank experiment, two sinkers of two different colors are placed in a compartmentalized corner of the rectangular tank, and a CCD camera records the choice behaviors of the octopuses to the colored sinkers. In the field experiment, the catch investigation of octopus for each colored sinker was conducted 14 times in total by using 2(A, B) commercial fishing boats at the coast of Gangneung within 30m of depth in 2006. The number of colored sinkers per operation was a total of 24-40 pieces with the same number of sinkers individually for four colors. As a result, it was found that the octopus selected white the most followed by black and yellow in their choice of colored sinkers in the water tank experiment, and green was the lowest in their choice. Even in the field experiment, the sinkers of white and black showed a higher catch of octopus than the sinkers of yellow and green.

TV광고 모니터링을 위한 비디오 워터마킹 시스템의 설계에 관한 연구 (A Study on the design of Video Watermarking System for TV Advertisement Monitoring)

  • 신동환;김성환
    • 전기학회논문지
    • /
    • 제56권1호
    • /
    • pp.206-213
    • /
    • 2007
  • In this paper, The monitoring system for TV advertisement is implemented using video watermark. The functions of the advertisement monitoring system are monitoring the time, length, and index of the on-air advertisement, saving the log data, and reporting the monitoring result. The performance of the video watermark used in this paper is tested for TV advertisement monitoring. This test includes LAB test and field test. LAB test is done in laboratory environment and field test in actually broadcasting environment. LAB test includes PSNR, distortion measure in image, and the watermark detection rate in the various attack environment such as AD/DA(analog to digital and digital to analog) conversion, noise addition, and MPEG compression. The result of LAB test is good for the TV advertisement monitoring. KOBACO and SBS are participated in the field test. The watermark detection rate is 100% in both the real-time processing and the saved the processing. The average deviation of the watermark detection time is 0.2 second, which is good because the permissible average error is 0.5 second.

자기장 통신을 위한 매체 접근 제어 프로토콜의 성능분석 (Performance Analysis of a Media Access Control Protocol for Magnetic Field Communication)

  • 정의훈;원윤재;김선희;임승옥;방영철
    • 한국통신학회논문지
    • /
    • 제36권5A호
    • /
    • pp.464-472
    • /
    • 2011
  • 우선 센서 네트워크 기술이 환경 감시나 재난 감시와 같은 다양한 용용 분야에 적용되면서 지중 환경에서의 무선통신에 대한 필요성이 증가하고 있다. 특히, 지중에서는 기존의 전자기파를 이용한 우선 통신 방식이 비효율이기 때문에 그 대안으로서 자기장을 이용한 지중 통신 기술이 제시되었고, 최근 들어 자기장 통신 기술이 국내 KS 규격으로 제정되었다. 본 논문에서는 KS 규격으로 제정된 자기장 통신 매체 접근 제어(Media Access Control) 프로토콜의 성능을 분석 및 시뮬레이션 방법을 통해서 분석한다.

Effect of Chemical Amendments on Soil Biological Quality in Heavy Metal Contaminated Agricultural Field

  • Kim, Yoo Chul;Hong, Young Kyu;Oh, Se Jin;Oh, Seung Min;Ji, Won Hyun;Yang, Jae E.;Kim, Sung Chul
    • 한국토양비료학회지
    • /
    • 제48권2호
    • /
    • pp.146-152
    • /
    • 2015
  • Heavy metal pollution has been a critical problem in agricultural field near at the abandoned metal mines and chemical amendments are applied for remediation purpose. However, biological activity can be changed depending on chemical amendments affecting crop productivity. Main purpose of this research was to evaluate biological parameters after applying chemical amendments in heavy metal polluted agricultural field. Result showed that soil respiration (SR) and microbial biomass carbon (MBC) were changed after chemical amendments were applied. Among three different amendments, lime stone (LS), steel slag (SS), and acid mine drainage sludge(AMDS), AMDS had an effect to increase SR in paddy soil. Comparing to control ($93.98-170.33mg\;kg^{-1}day^{-1}$), average of 30% increased SR was observed. In terms of MBC, SS had an increased effect in paddy soil. However, no significant difference of SR and MBC was observed in upland soil after chemical amendment application. Overall, SR can be used as an indicator of heavy metal remediation in paddy soil.

시간 역전을 기반으로 한 지능적 원거리 무선전력전송 (Smart Far-Field Wireless Power Transfer via Time Reversal)

  • 박홍수;홍하영;홍순기
    • 한국전자파학회논문지
    • /
    • 제29권4호
    • /
    • pp.285-289
    • /
    • 2018
  • 본 논문에서는 지능적인 원거리 무선전력전송의 방식으로 시간 역전(time reversal) 기반 전파 집속 방법을 제시하였다. 시간 역전 기반의 무선전력전송은 복잡한 전파환경에서도 기기의 위치에 상관없이 전파를 선택적으로 집속하여 높은 peak 전력을 전달할 수 있다. 현실과 가까운 전파환경 시뮬레이션을 통하여 시간 역전 기반의 시 공간 전파 집속 현상을 검증하였고, 집속된 RF를 정류하여 전달된 DC 전압을 확인하였다. 또한 일반적인 협대역 신호(CW) 대비 시간 역전 신호의 peak 향상률과 정류 전력비를 확인한 결과, 최대 12 dB 향상된 peak 전력이 전송되었으며, 따라서 보다 높은 효율로 전력전송이 이루어짐을 확인하였다.

경북대 캠퍼스 내 대기환경 및 미규모 모델(MUKLIMO)을 이용한 바람장 모의 연구 (A Study on the Atmospheric Environment and Simulations of Wind Field using MUKLIMO at the KNU Campus)

  • 민경덕;윤지원;안광득
    • 한국환경과학회지
    • /
    • 제14권3호
    • /
    • pp.311-325
    • /
    • 2005
  • Elements of atmospheric environment, temperature, humidity and wind, at the compus of KNU(Kyungpook National University) were investigated by the observations. The observed data were compared with those of DWS (Daegu Weather Station). The simulations of wind field and dispersions of polluted gases were conducted by MUKLIMO under the various conditions. The results show that the atmospheric environment of KNU are suitable but the campus does not play role as a heat sink in the city. The simulations of wind field show the air flows and wind channels in the campus clearly. The exhausted gases by motor vehicles on the northside street of campus affect very much to the campus with $NW(300^{\circ})$ wind. The running cars in the campus are also pollute much on the campus with the various wind directions. The characteristics of environmental conditions, various meteorological fields, wind channels, and dispersion of exhausted gases at the campus of KNU were understood quantitatively in the study.