• 제목/요약/키워드: Environment for Test

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전산유체역학을 이용한 디젤엔진 부하시험장의 환기 개선에 관한 연구 (A Study on the Ventilation Improvement of Diesel Locomotive Engine Load Test Building using Computational Fluid Dynamics)

  • 박덕신;정병철;조영민;박병현
    • 한국대기환경학회지
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    • 제21권2호
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    • pp.227-242
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    • 2005
  • The aim of this study is to relieve the poor ventilation problem of the diesel locomotive engine load test building, located in an urban area. This paper evaluates the ventilation performances of the studied load test building based on the temperature measurement experiment and the computational fluid dynamics (CFD) during the engine load test. The temperature rise caused by the radiator blower of the building was turned out to be the main cause of disturbing the thermal conditions of the building. The indoor temperature distributions simulated by Fluent were validated with the temperature measurement results obtained from the studied building. The simulation results indicated that the comfort condition of this building was poor We suggested several remedial changes in the duct structure of this building for the improvement of the comfort conditions. In addition, a prototype drawing combining several improved design options was proposed. and then the simulation of the temperature distribution in the proposed prototype was performed. The result indicated that the indoor thermal condition of this proposed building was improved when compared with that of the current building.

인공위성발사체 상단부 진동환경시험을 위한 치구설계 (Vibration Fixture design for small satellite launch vehicle environment test)

  • 정호경;서상현;박순홍;장영순;이영무
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2007년도 춘계학술대회논문집
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    • pp.258-262
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    • 2007
  • Satellite launch vehicle is exposed to some dynamic environment during its flight. Particularly, the safety of launch vehicle structure is surely verified under vibration environment in low frequency range. Sine sweep test is generally performed to describe this low frequency vibration environment. Dynamic property of vibration fixture is considered to get the correct property of target object. This vibration fixture should really be an extension of the armature in the form of a very rigid structure that can transfer the required force at the required frequency. An optimum fixture would have its lower natural frequency about 50% higher than the highest required forcing frequency in order to avoid fixture resonances during the test. In this study, the vibration mode analysis considering the mass of target object to design the vibration fixture. And the modal test of vibration fixture is performed to conform the design.

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평면투수 실험을 통한 기존 배수재와 고투수성 배수재의 성능 평가 (Performance Assesment of the Existing Tunnel drain and higher permeable for the In-plane Test)

  • 마상준;이흥수;최희섭;김경덕
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2008년도 추계 학술발표회
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    • pp.1581-1584
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    • 2008
  • In this study, performance Assesment of the existing tunnel drain and higher permeable for the In-plane Test. Two separate simulation tests from geotexitile and Lightweight Foamed Mortar compare. perfomed:the one is the in-plane test and the other is the clogging phenomenon test. As a result, NATM Composite used to Ligheweight Foamed Mortar pemability 80%, more than existing tunnel drain. Also, clogging phenomenon test do low assesment more than existing tunnel drain geotextile.

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A Study of Ecotoxicity Test for Byproducts of Ozone in the Ballast Water Treatment System with Ozonation

  • Park, Sung-Jin;Ha, Shin-Young;Kim, In-Soo
    • 한국항해항만학회지
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    • 제35권9호
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    • pp.741-747
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    • 2011
  • Ecological toxicity testing of the whole-effluent from the ozone ballast water treatment system was conducted as specified in the quality assurance project plans (QAPP). The growth inhibition test with microalgae, acute aquatic toxicity test with the Rotifer reproduction, toxicity test (or population growth) with the Rotifer, survival and growth toxicity test with larval fish and sediment toxicity test with amphipod were carried out to evaluate ecological toxicity on the movile test barge.

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

  • 신동환;김경순;김종원;최종욱
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 학술대회 논문집 정보 및 제어부문
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    • pp.15-18
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    • 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.

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충남대학교 고고도 우주환경모사 진공실험 장치 (Vacuum Facility at the CNU for High Altitude Space Environment Test)

  • 신강창;이민재;정성철;김연호;김혜환;허환일
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2007년도 제28회 춘계학술대회논문집
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    • pp.49-52
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    • 2007
  • 마이크로 인공위성에 적용 가능한 마이크로 추력기를 개발하기 위해서는 우주환경을 모사할 수 있는 진공설비가 요구된다. 본 논문에서는 $10^{-5}$ torr의 진공도를 유지할 수 있는 진공설비를 구축하였고, 이 장비는 $100{\sim}120km$의 고도를 모사할 것으로 기대된다. 실제 장비운용에 앞서 사용할 펌프의 성능을 예측하고 저진공 펌프를 작동시켜 이론에 의한 예상 진공도와 실험을 통한 진공도를 비교 분석하였다.

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태백지역 석탄광산의 호흡성 분진 폭로 농도 (The Exposure Level of Respirable Dust of Underground Coal Mines in Taebaek Area)

  • 윤영노;이정주
    • 한국대기환경학회지
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    • 제4권1호
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    • pp.23-32
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    • 1988
  • The exposure level of respirable dust and silica for the coal workers of underground coal mines in Taebaek area was evaluated. Personal air samplers were attached to the coal workers-drillers, coal cutters, their helpers, haulers, and separators. Normality and lognormality of respirable dust and silica concentrations were tested by Kolmogorov-Smirnov one-sample test, differences of means of respirable dust and silica concentration were tested by group-t-test and paired t-test, and relation between respirable dust and silica concentration were tested by regression test.

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지구관측위성의 발사환경시험 요구조건 (Launch Environment Requirements for Earth Observation Satellite)

  • 김경원;김성훈;김진희;이주훈;황도순
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 추계학술대회논문집
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    • pp.747-750
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    • 2004
  • After launching, spacecraft is exposed to extreme environments. So spacecraft should be tested after design/manufacture to verify whether components can be operated functionally. Acceleration transferred from launch vehicle to spacecraft produces quasi-static load, sine vibration and random vibration. Random vibration is also induced by acoustic vibrations transferred by surface of spacecraft. And shock vibration is produced when spacecraft is separated from launch vehicle. To verify operation of spacecraft under these launch environments, separation shock test, sine vibration test, acoustic vibration test and random vibration test should be performed. This paper describes these launch environment test requirements.

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인공위성 개발을 위한 유닛 열시험 개요와 실제 (Overview of Thermal Test and Practice in Developing Satellite)

  • 서정기;장태성;차원호
    • 한국항공우주학회지
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    • 제41권11호
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    • pp.915-920
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    • 2013
  • 인공위성 내부 유닛들이 위성에 실장 되기 위해서는 각 위성 프로그램에서 요구하는 다양한 환경시험을 반드시 통과해야 한다. 최근 타 분야의 기술이 우주분야로 이전되면서 다양한 인공위성 탑재체들이 개발되고 있다. 하지만, 타분야 개발자의 경우 우주개발에 대한 경험 및 이해부족으로 발사 및 우주환경시험을 수행함에 있어 다양한 문제점을 접하게 된다. 본 기술논문에 위성개발 각 단계에서 수행되는 열시험의 개념을 서술하여 우주분야 기술개발을 처음으로 수행하는 개발자가 열시험을 준비하는데 실제적인 도움을 주고자 한다.

Slug Interference Tests: Performance and Comparison

  • 이진용;이명재;최예권;김용철
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2001년도 추계학술발표회
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    • pp.184-187
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    • 2001
  • This study presents procedure and analysis method for not well known slug interference tests. Results of the slug interference tests were compared with those of pumping and recovery tests and conventional slug tests.

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