• Title/Summary/Keyword: environmental test

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Environmental Test of Avionics Equipment for Lightning Indirect Effect (낙뢰 간접영향에 대한 항공전자장비의 환경시험)

  • Jeong, Duck-young;Yang, Hyun-duck
    • Journal of Aerospace System Engineering
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    • v.7 no.2
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    • pp.55-59
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    • 2013
  • Before avionics equipment are installed in aircraft, several environmental tests such as temperature, vibration, lightning, fire etc. must be conducted. One of the environmental tests is to substantiate protection designs of lightning indirect effect. It can be showed through RTCA DO-160G, section22 "Lightning Induced Transient Susceptibility" test. An additional test of aircraft level is required as well after installation of avionics equipment.

A Study on Housewives′ Pro-Environmental Behavior and it′s Determinants in Urban Area (도시주부의 환경친화적 행동과 영향요인에 관한 연구)

  • 곽인숙;이경희;홍성희
    • Journal of the Korean Home Economics Association
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    • v.41 no.12
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    • pp.169-186
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    • 2003
  • The purpose of this study were (1) to examine the level of housewives' pro- environmental behavior, and (2) to analyze the effect of the selected variables on pro-environmental behavior 941 sample were selected from housewives living in urban area. For the analysis of data, frequencies, means, one-way ANOVA, DMR test, Chi-square test, and multiple regression analysis were used. The major findings were as follows:1. The level of housewives' pro-environmental behavior was lower than that of pro-environmental attitude. 2. The level of housewives' pro-environmental behavior was mainly affected by their environment-related variables, for example, pro-environmental attitude, and experience of environmental education. Most of socio-demographic variables and family-related variables didn't have significant effects on the level of pro-environmental behavior.

The Mass Production Weapon System Environmental Stress-Screening Test Design Method based on Cost-effective-Optimization (비용 효과도 최적화 기반 양산 무기체계 환경 부하 선별 시험 설계 방법)

  • Kim, Jangeun
    • Journal of Applied Reliability
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    • v.18 no.3
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    • pp.229-239
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    • 2018
  • Purpose: There is a difficulty in Environmental Stress Screening (ESS) test design for weapon system's electrical/electronic components/products in small and medium-sized enterprises. To overcome this difficulty, I propose an easy ESS test design approach algorithm that is optimized with only one environment tolerance design information parameter (${\Delta}T$). Methods: To propose the mass production weapon system ESS test design for cost-effective optimization, I define an optimum cost-effective mathematical model ESS test algorithm model based on modified MIL-HDBK-344, MIL-HDBK-2164 and DTIC Technical Report 2477. Results: I clearly confirmed and obtained the quantitative data of ESS effectiveness and cost optimization along our ESS test design algorithm through the practical case. I will expect that proposed ESS test method is used for ESS process improvement activity and cost cutting of mass production weapon system manufacturing cost in small and medium-sized enterprises. Conclusion: In order to compare the effectiveness of the proposed algorithm, I compared the effectiveness of the existing ESS test and the proposed algorithm ESS test based on the existing weapon system circuit card assembly for signal processing. As a result of the comparison, it was confirmed that the test time was reduced from 573.0 minutes to 517.2minutes (9.74% less than existing test time).

A Study on an Environmental Test Sequence for Electrical Units on Aircraft (항공기 전장품의 환경시험순서에 관한 연구)

  • Yang, Jung Ho;Kim, Yong Soo
    • Journal of Applied Reliability
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    • v.14 no.2
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    • pp.114-121
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    • 2014
  • An environmental test has been performed in order to improve the lifetime and reliability of the electrical units on aircraft. However, faults occurring in the field of aircraft have been difficult to predict and prevent, and new concepts for reliability testing are desired. Therefore, a composite reliability test sequence was proposed in the conventional studies. This study introduces test sequence guidelines based on relevant principles and considerations for electronic testing according to International Standard IEC-60068-1 and the United States Military Standard MIL-STD-810G. In addition, we analyze possible causes of failure using two-step QFD based on aircraft operation scenarios. Finally, the proposed test sequence can reproduce various and realistic failure modes for electrical units on aircraft.

Noise Test and Evaluation of a 750kW Wind Turbine Generator (750kW 풍력발전기의 소음실증)

  • Kim, Seock-Hyun;Heo, Wook;Lee, Hyun-Woo
    • Journal of Industrial Technology
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    • v.27 no.B
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    • pp.59-64
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    • 2007
  • This study introduces an environmental noise evaluation procedure and results for a wind turbine (W/T) system. Test and evaluation are required by the international standard IEC 61400-11 in the aspect of environmental effect. Test and evaluation are performed on U-50 WT model which is first developed by the domestic W/T manufacturer. W/T test model is under operation in Daekwanryung wind test site. An integrated monitoring system in the test site is utilized for the evaluation. With the noise signal, meteorological data and W/T operational data are monitored in real time by the integrated monitoring system using LabVIEW. From the measured noise data, acoustic power level are estimated and compared with those of other similar size WT under the wind speeds required by international standard.

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Statistical Study on the Measurement Assurance Program in Environmental Pollution Measurement Activities -The Round-Robin Test about Water Pollution- (水質汚染物質의 共同試料分析調査)

  • 李載昌;申漢豊;李樂榮
    • Journal of the Korean Statistical Society
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    • v.9 no.2
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    • pp.194-212
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    • 1980
  • This report describes a preliminary study necessary to implement Measurement Assurance Program (MAP). The purpose of the study is to improve the measurement reliability of the laboratories which take environmental pollution measurement. We carried out the interlaboratory test or "Round-Robin" test program in which seven laboratories participated in order to obtain more reliable data about water pollution.pollution.

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Leaching Characteristics of Heavy Metals of Bottom Ash and Plating Sludge with Environmental Conditions in Landfill (매립지 환경조건을 고려한 소각재와 도금슬러지의 중금속 용출특성)

  • 손희정;김은호;이용희
    • Journal of environmental and Sanitary engineering
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    • v.13 no.2
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    • pp.121-127
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    • 1998
  • This study was to understand leaching characteristics with pH controlling agents and Temp. control, and investigate leaching characteristics with pH control from opening a leaching test to an end for reassessing leaching test of heavy metals with environmental conditions in landfill. Because leaching of heavy metals was increased in low pH, pH must control for leaching in existing leaching test. Generally, regulation time(6hr) of leaching was confirmed reasonablely, except for Cu in plating sludge. In pH controlling solution, there was nearly not difference between Acetic acid and HCl and if considering Cu, the former was appropriate. In a part of heavy metal, leaching rate was increased in high Temp., and normal Temp. in existing leaching test would be revaluated.

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The Clothing Consumption Behavior of Fast Fashion Purchaser according to Environmental Consciousness (환경의식에 따른 패스트패션 구매자의 의복소비행동에 관한 연구)

  • Lee, Hyun Ji
    • Fashion & Textile Research Journal
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    • v.17 no.4
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    • pp.550-560
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    • 2015
  • This study investigates clothing consumption behavior of fast fashion purchasers according to environmental consciousness. Questionnaire examined 245 males and females in Busan who experienced fast fashion product purchases. Data were analyzed using factor analysis, t-test. ANOVA, Duncan Test and ${\chi}^{2}-test$. The results are as follows. First, the result showed significant differences in environmental consciousness education according to demographic characteristics. Second, the results showed significant differences in the hedonic pursuit of purchase motivation for fast fashion products according to environmental consciousness. The low environmental awareness group pursued hedonic purchases towards the purchase motivation of fast fashion products. The results showed significant differences in fast fashion disposal behavior according to environmental consciousness; however, not for the disposal motivation of fast fashion. In the disposal behavior of fast fashion, the high environmental awareness group indicated social friendly disposal and the middle environmental awareness group indicated economical disposal. The result showed significant gender differences towards clothing consumption behavior of fast fashion according to demographic characteristics. Males and females showed significant differences in all purchase motivation factor for fast fashion products. They also showed significant differences in economical disposal towards fast fashion disposal behavior.

Toxicity Assessment of PFOA and PFOS Using Freshwater Flea Hyalella azteca (담수산 물벼룩인 Moina macrocopa를 이용한 과불화화합물 PFOA와 PFOS의 독성평가)

  • Lee, Chul-Woo;Kim, Hyun-Mi;Choi, Kyung-Hee
    • Environmental Analysis Health and Toxicology
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    • v.22 no.3
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    • pp.271-277
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    • 2007
  • Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) are fully flurorinated organic compounds which are highly persistent in environment and accumulated in organism. These chemicals are released to the environment at their manufacture, during their use in industrial and consumer applications and from disposal after their use. The purpose of this study was to determine the effects of PFOA and PFOS on the freshwater flea (Moina macrocopa). Acute toxicity test and chronic toxicity test were performed for 2 days and 10 days, respectively. Acute toxicity was assessed on the basis of mortality, while chronic toxicity was assessed by fecundity as well as mortality. The acute toxicity studies on PFOA and PFOS showed that the values of $LC_{50}$ were $73.9\;mg/L\;and\;27.7\;mg/L$ respectively. In the chronic toxicity test, fecundity was reduced significantly at 24.1 mg/L of PFOA and 9.3 mg/L of PFOS, respectively. Conclusively, the results of this work suggest that Moina macrocopa could be a suitable model organism for screening and assessing of environmental pollutants in water.

Acute Toxicity Test of Agricultural Chemicals to Water Fleas (물벼룩을 이용한 농약의 급성 독성에 관한 연구)

  • Lee, Chan-Won;Ryu, Jae-Young;Lim, Kyeong-Won
    • Journal of Environmental Science International
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    • v.16 no.1
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    • pp.55-63
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    • 2007
  • There are concerns that chemical residues could harm the consumer on the environment, although 50 to 80% of the crops would be destroyed by pests and others without agrochemicals. Environmental fate and ecotoxicity studies are usually carried out to assess the impact on the human and the environment. A comparision of the Daphnia magnia and Simocephalus mixtus toxicity was performed to study the relative sensitivities and discrimination abilities to agriculture chemicals. The species of Simocephalus mixtus was more sensitive to agriculture chemicals than Daphnia magnia. Simocephalus mixtus was approved to be a water flea in determining insecticide and pesticide toxicity by heart-beat rate in a consistency and repeatability. The order of acute toxicity to water flea Daphnia magnia for ecotoxicity test was carbaryl>benomyl>amtirole with both Daphnia magnia and Simocephalus mixtus. The heartbeat pattern after the exposure to agrochemicals was different from that of exposure to heavy metals. Agrochemical leathal concentration test with heartbeat rate measurement was found to be more appropriate than inhibition concentration test with respect to toxicological endpoint.