• 제목/요약/키워드: Laboratory experiment

검색결과 2,588건 처리시간 0.025초

ANALYSIS ON MICROBIOLOGICALLY INFLUENCED CORROSION FAILURE CASE OF SUS316L STAINLESS STEEL WELDS

  • Miyano, Yasuyuki;Yamamoto, Michiyoshi;Watanabe, Kazuya;Kikuchi, Yasushi
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2002년도 Proceedings of the International Welding/Joining Conference-Korea
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    • pp.133-138
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    • 2002
  • Microbiologically Influenced Corrosion (MIC) was suspected in a corrosion failure of cooling system of stainless piping welded joint, carrying marine water. Marine water which is used for cooling water in a plant was transferred to the laboratory and used for experiment. In the first experiment, weld metal samples were exposed to the test solution for 56 days (marine water and sterilized marine water (control)). Surface condition of experimental coupons was observed using a Scanning Electron Microscope (SEM). In another experiment, free corrosion potential of these material was monitored for 56 days. Pitting corrosion was found in the coupons exposed to marine water. Free corrosion potential ennoblement was found to be significant compared to control. It was suspected that this corrosion case was MIC. In the second experiment, coupons were exposed to diluted nutrient medium containing single culture of microbes isolated from the MIC causing marine water sample used for the first experiment. After exposure test, surface condition of experimental coupon was observed using SEM. Pitting corrosion was found in coupons exposed to some of the isolates. The results indicate that they contribute to the corrosive effect of the SUS316L welds.

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헤드폰을 이용한 가청역치레벨의 측정 방법 비교 (Comparison of a hearing threshold level using a headphone)

  • 김득성;장서일;김동준;이연수
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2007년도 추계학술대회논문집
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    • pp.796-801
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    • 2007
  • This research presents a laboratory study about a comparison between two methods that measure a hearing threshold of the Subjects who participated in an experiment of the Jury test. The Subjects heard a signal by a headphone. The Subjects of total 63 persons (man=42, woman=21 persons) participated in an experiment. A test of hearing was divided into two (Top-Down, Bottom-Up) methods. Total time of hearing test was about 80 minute(40min/day). As a results of the hearing test, a hearing threshold of the Subjects who used to wear a headphone was higher than that of the Subjects who not used to wear a headphone. A hearing threshold of a man was higher than that of a woman. The result of hearing test was showed that ISO's hearing threshold(MAF) was lower than a result that get from an experiment.

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소형어선에 있어서 자기 컴퍼스를 이용한 자동항법시스템의 정도 (Precision of Autopilot System using Magnetic Compass in Small Fishing Boat)

  • 이유원
    • 수산해양교육연구
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    • 제19권3호
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    • pp.510-516
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    • 2007
  • The efficiency of magnetic compass direction sensor and magnetic compass by the laboratory experiment for the apparatus of generating artificial magnetic force and the onboard experiment on the fishing boat of coastal pot at the outside of Pusan Namhang were investigated. The results showed that the bearing angle of magnetic compass direction sensor was coincided with that of magnetic compass. However, the performance of magnetic compasses was unsuitable under the ISO rule by the characteristic experiment of damping curve. Therefore, the use of autopilot system using magnetic compass direction sensor which is based on the magnetic compass needs the sufficient notice.

소변검사의 검체 채취 방법에 관한 임상실험연구 (A Clinical Trial on the Method of Urine Sampling for Urinalysis)

  • 안혜성;이성은;박현옥
    • 기본간호학회지
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    • 제2권2호
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    • pp.131-137
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    • 1995
  • Improving validity and reliability is the important components of clinical laboratory tests. And the quality control of the test should be started with the accurate collection of specimen. Urinalysis is one of the useful and common tests in diseases diagnosis and determining the process of medical treatment. Since urinalysis is requested routinely in hospital setting, the importance of the quality control for urine specimen is often ignored. To improve the validity of urinalysis, a clinical trial was done on the method of collecting urine specimen. The result was as follows : 1. The rate of presumtive UTI(urinary tract infection) was decreased in 21.6% with experiment method for collecting urine specimen. 2. The rate of presumtive UTI in female patients was decreased in 43.2% with the experiment method. 3. The rate of negative urine culture was decreased in 6.6% with the experiment method.

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Use of Terrestrial Hyperspectral Sensors for Analyzing Spectral Reflectance Characteristics of Concrete

  • Lee, Jin Duk;Lee, Sung Soon;Sim, Jung Bo
    • 한국측량학회지
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    • 제32권3호
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    • pp.185-190
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    • 2014
  • The purpose of this research is to extract spectral reflectance characteristics of concretes through basic experiment on concrete specimens and site experiment on actual concrete structures using a field portable spectrometer and a VNIR hyperspectral sensor. A spectrometer (GER-3700) and a VNIR hyperspectral camera (AisaEagle VNIR Hyperspectral Camera) were utilized for extracting spectral characteristics of concrete specimens. Concretes normally show similar patterns that have correlation above 80%, while the high-strengthened concretes display very different results from the normal-strength concretes. We also made a certain conclusion in the laboratory experiment on concrete specimens that both the spectrometer and the VNIR camera vary in spectral reflectance depending on concrete strengths.

자동차 조립작업 시 작업자세, 작업/휴식비율, 작업형태에 따른 작업부하의 변화에 관한 연구 (A Study of Workload Change at Varying Working Posture, Work/Pest Ration and Task Type in an Automobile Assembly Task)

  • 이준엽;김철홍
    • 산업경영시스템학회지
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    • 제24권69호
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    • pp.51-64
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    • 2001
  • A laboratory experiment was conducted to investigate the effects of working posture. work/rest ration, and task type on the physical workload in automobile assembly jobs. Ten healthy male university students participated as subjects in the experiment. East subject performed 18 experimental session with combination of 3 working posture 3 work/rest ratio and 2 task types. To examine the effect of various working conditions on workload, DMG analysis was performed on 4 different muscles in the neck an arm area, Also RPE scale and heart rate were taken as response variables. The result showed that all working conditions considered in the experiment had significant effects on the workload concluding that labor intensity in auto assembly jobs should be adjusted with respect to different levels of working posture, work/rest ratio, and task type. Detailed analysis are presented in the paper.

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컴퓨터 네트워크 가상 실습을 위한 컴포넌트 기반의 시뮬레이터 설계 및 구현 (Design and Implementation of a Component-based Simulator for the Virtual Laboratory of Computer Networks)

  • 임명식;김기형
    • 한국시뮬레이션학회논문지
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    • 제12권1호
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    • pp.1-10
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    • 2003
  • Recently, various network protocols have been developed to keep step with the rapid growth of Internet users. For the education of students in the computer networks classes, there have been many attempts to allow students experiment routers setting, operations and management of networks by themselves, in addition to the classroom lectures based on textbooks. One of the attempts is to install expensive real router experiment sets in laboratories for students, and one another is using router and network simulators for virtual experiments. This paper presents the design and implementation of NetSim, a scalable, component-based simulator environment for the network experimentation. NetSim expands the existing component-based JavaSim simulation tool for the education purpose, and it allows the design and experiment of various networks and protocols. For the evaluation of NetSim, it is shown that the network design and RIP-based router setting process is possible in NetSim.

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웹 기반의 계측기 사용법 컨텐츠 개발 (Contents production of a web-based manual for a measuring instrument)

  • 안덕상;이순흠;최관순;김동식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 D
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    • pp.2600-2602
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    • 2001
  • The laboratory time for students in engineering has to be managed in that way that it provides students width maximal practice hours. However, it usually takes too much time to learn basic knowledge for the experiment and the directions of the equipment. In this paper, we introduce the web contents which students can study basic knowledge the directions of the equipment without regard to time or place. As the result that we let students study the contents before the class, they were easily adapted to handle the equipments for the experiment so that we can revise their execution abilities. And also there were effects such as reducing the total experiment's time and a rate of damage of equipment.

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Development of Web-Based Experiments for Undergraduate Mechatronics Education

  • KIM, Young-Suk;Yang, Seung-Han
    • Educational Technology International
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    • 제14권2호
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    • pp.215-228
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    • 2013
  • In engineering education practical experiments is very important for each student, but due to the limitation of time and available resources such as laboratory equipment, space and instructors enough hands-on real experiments could not be provided to all students enrolled in the program throughout the academic year. In this sense web-based remote experiments through internet become a solution for engineering education and an emerging new paradigm for students and teachers. This paper presents the development of the web-based remote vibration experiment system for mechatronics education. Students can access this experimental equipment through an internet and conduct vibration experiment remotely without any restriction on time and place. IP address for data communication and web-service are assigned in local computer and then students receive experimental results and the captured pictures using network. The developed system provides real-time feedback of the tested results. Ubiquitous access to the system gained popularity from students.

생물안전 3등급 연구시설의 구성 및 이용 (Composition and Use of Biosafety Level 3 Facility)

  • 김창환;허경행;이완걸;정성태
    • 한국군사과학기술학회지
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    • 제18권3호
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    • pp.335-342
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    • 2015
  • Laboratory facilities for biology are designed as biosafety level 1, biosafety level 2, biosafety level 3, and biosafety level 4. Biosafety level designations are based on a composite of the design features, construction, containment facilities, equipment, practice and operation procedures required for working with agents from the various risk groups. Generally, biosafety level 3 means the facility that is appropriate for the experiments using pathogens which can cause serious diseases by aerosol transmission. The biosafety level assigned for the specific work to be done is driven by professional judgement based on a risk assessment, rather than by automatic assignment according to the particular risk group designation of the pathogenic agents to be used. In this paper, we introduced the biosafety level 3 facility operated in ADD(Agency for defense development). It contains the overview of facility, microbiological experiment, animal experiment, decontamination and waste disposal. Biosafety level 3 laboratory in ADD has served the vital role in the research of biological agents and antidote development.