• 제목/요약/키워드: Environmental tests

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

  • 정덕영;양현덕
    • 항공우주시스템공학회지
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    • 제7권2호
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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.

STANDARDIZATION OF TEST ORGANISMS AND DEVELOPMENT OF TOXICITY TESTS METHODS

  • Yasuno, M.
    • 한국환경독성학회:학술대회논문집
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    • 한국환경독성학회 1993년도 제12회 총회 및 학술 발표회 특별강연요지집
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    • pp.4-5
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    • 1993
  • Toxicity tests in our laboratory are conducted usually with mass-reared organisms. They are under the same environmentel conditions throughout seasons and are supplied at specific age. A total of 38 species of aquatic organisms are being reared. We have attempted to establish pruified strains or to select clones of various parthenogenic organisms. The merits or demerits of our culturing test organisms are discussed. The differences in the susceptibility among clones or strains of test organism are also discussed. For a single species test, algae, daphnia, fish are often used. However, we usually use early stages, but occasionally, adults fish are used for reproduction tests. As an another important aspect, the toxicity through food chains has been studied. In this study, we select a pair of species belonging different trophic levels. The differences between single species tests and multispecies tests will be discussed. Even a single species test intends to assess the effects of chemicals on ecosystem levels, however, this idea is not applicable to ecosystems. Single species tests with standard organisms and multispecies tests are contradictory in concept. One type of multispecles tests is indoor microcosms being composed of severel species artificially assembled, and another is composed of natural components (both indoor and outdoor). We have used three types of outdoor mesocosms using ponds and three types of artificial streams. The mesocosms is useful to not only to analyze the floral or faun61 changes but also to study the fate or behaviour of chemicals in naturd environments. Lastly, usefulness of the field observation or experiments or semi-field experiments will be discussed. This will enhance the exploitation of early warning systems utilizing indicator organisms or animal behaviour.aviour.

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광고를 활용한 환경교육이 유아의 환경친화적 태도 및 환경보전 지식에 미치는 효과 (A Study on the Effect of Environmental Education Using the Advertisement on Children's Eco-Friendly Attitude and Environmental Preservation Knowledge)

  • 임수민;안효진
    • Human Ecology Research
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    • 제54권5호
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    • pp.451-459
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    • 2016
  • This study was to develop environmental education activities using advertisement as well as investigate the effect of environmental education using advertisements on children's eco-friendly attitudes and environmental preservation knowledge. The effect of the environmental education activity using advisements was examined based on 24 children aged five attending a daycare center located in Incheon metropolitan city (12 in the experimental group and 12 in the control group). This study was executed 12 times (twice a week) in both the experimental group and comparative group as the environmental education using advertisements was developed and executed in the experimental group as environmental education according to the life theme's in the Nuri curriculum of the comparative group. The instruments used in this study were the children's eco-friendly attitude scale (two factors, 18 items) and environmental preservation knowledge scale (four factors, 16 items). Children's eco-friendly attitude and environmental preservation knowledge were assessed by pre-tests and post-tests using the SPSS ver. 18.0 program. Results indicated that after 6 weeks application, the experimental group exhibited higher scores than the control group in the children's eco-friendly attitude as well as environmental preservation knowledge. This study showed that environmental education activities using advertisement had a positive effect on children's eco-friendly attitudes and environmental preservation knowledge.

시멘트 고결체의 양생수에 따른 강도특성 및 환경적 영향에 관한 연구 (Strength Characteristics of Solidified Cement Grout on Curing Solution and Environmental Effects)

  • 천병식;이재영;김경민
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2003년도 봄 학술발표회 논문집
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    • pp.689-696
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    • 2003
  • In this study, ordinary portland cement, slag cement and micro cement which have been used in the construction fields were evaluated for the environmental effects and compression strength characteristics for curing solution. To find the leaching of C $r^{6+}$ characteristics in cement grouts, C $r^{6+}$ content tests were performed for the raw materials(cement powder). In addition, C $r^{6+}$ leaching tests were peformed for the homo-gel samples according to change of pH and each curing solution with the deionized water and leachate. Then, the unconfined compression strength tests were peformed with the homo-gel samples and the amount of changed C $r^{6+}$ was measured by curing solution.

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물벼룩에 있어 bisphenol A의 embryo독성 (Embryotoxicity of Bisphenol A in Daphnia magna)

  • 황갑수
    • Environmental Analysis Health and Toxicology
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    • 제21권1호
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    • pp.81-86
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    • 2006
  • Embryotoxicity tests were performed in Daphnia magna to assess aquatic ecotoxicity of bisphenol A, a well known industrial compound showing estrogen-like activity in vivo, and to examine their effectiveness in the toxicological assessment. The whole embryonic developmental period was classified into 6 stages and developmental abnormality was checked to evaluate the embryotoxicity. In the present study, bisphenol A showed the ability to interfere with embryonic development, suggesting its antiecdysteroidal activity. The rates of mortality, delayed development, deformity and immobility all showed good concentration-response relationship, demonstrating their possibility as useful toxicological indices in daphnid embryotoxicity tests that have been rarely performed so far. It seemed favorable to the test sensitivity that embryos are removed from maternal daphnids around 7 hr after deposition from the ovaries to the brood chamber. These results suggest that daphnid embryotoxicity tests can be one of useful tools available for the assessment of ecotoxicity of various chemicals in the aquatic environment.

열상장비용 스터링 극저온 냉동기 특성평가 (III) : 열환경시험 (The performance evaluation of Stirling cryocooler for thermal imaging system (III) : Thermal environmental test)

  • 김양훈;박성제;홍용주;김효봉;고득용;이승홍;나종문
    • 한국초전도저온공학회:학술대회논문집
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    • 한국초전도저온공학회 2003년도 추계학술대회 논문집
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    • pp.163-166
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    • 2003
  • This paper presents the results of a series of performance tests for the Stilting cryocooler. Infrared sensor systems incorporating cryocoolers are required to be qualified to the appropriate environmental specification. Linear drive Stilting cryocooler have matured to the stage of undergoing formal qualification test program The thermal environmental test of the Stilting cryocooler is presented in this paper. We performed that low and high temperature keeping test from -4$0^{\circ}C$ to +6$0^{\circ}C$ and operating test at high and low temperature cyclic range with acceptance tests performed at scheduled intervals. Cooling capacity was determined as a function of cooler components temperatures at the compressor, hot end and cold tip. Tests performed on this cooler have been successful with a measured cooling performance of more than 0.8W@80K for 23$^{\circ}C$ ambient temperature with 40 $W_{ac}$ input power.

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국내 서식 담수새우 새뱅이(Neocaridina denticulata)를 이용한 3,4-Dichloroaniline의 급성독성 교차시험(Ring test) (Ring Test as Acute Toxicity Test with Korean Freshwater Shrimp, Neocaridina denticulata using 3,4-Dichloroaniline)

  • 신유진;이재우;김지은;조재구;김자현;강민호;김경태;김필제;박경화
    • 한국환경보건학회지
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    • 제45권3호
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    • pp.285-294
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    • 2019
  • Objectives: For suitable risk management of the domestic aquatic environment, it is necessary to conduct toxicity tests using species native to Korea. In the present study, we performed toxicity ring tests using endemic freshwater arthropoda Neocaridina denticulata and evaluated its validity and reproducibility as an international standard test species. Methods: To evaluate the sensitivity levels of N. denticulata to hazardous chemicals, toxicity values for several chemicals were compared with other standard test species. Intra- and inter-laboratory acute toxicity tests were performed both within a single laboratory and among four laboratories respectively using 3,4-Dichloroaniline, which is generally used as a reference test substance in fish toxicity tests. In addition, intra- and inter-laboratory coefficient of variations (CVs) were calculated to evaluate reproducibility based on the estimated toxicity values. Results: The sensitivity of N. denticulata to several chemicals was found to be similar with D. manga, indicating that the species is valid as a test species. The CVs of the intra- and inter-laboratory tests were 22.946% with four qualified runs and 8.828% among the four laboratories, respectively. Conclusions: N. denticulata serves in an important role in the food chain of Korean aquatic ecosystems and also inhabits several other Asian countries. Since the validity and reproducibility of the species were confirmed as a toxicity test species in this study, further efforts are needed to establish N. denticulata as the international standard test species for the appropriate risk assessment of aquatic ecosystems at home and abroad.

수질자료의 추세분석을 위한 비모수적 통계검정에 관한 연구 (A Study of Non-parametric Statistical Tests to Analyze Trend in Water Quality Data)

  • 이상훈
    • 환경영향평가
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    • 제4권2호
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    • pp.93-103
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    • 1995
  • This study was carried out to suggest the best statistical test to analyze the trend in monthly water quality data. Traditional parametric tests such as t-test and regression analysis are based on the assumption that the underlying population has a normal distribution and regression analysis additionally assumes that residual errors are independent. Analyzing 9-years monthly COD data collected at Paldang in Han River, the underlying population was found to be neither normal nor independent. Therefore parametric tests are invalid for trend detection. Four Kinds of nonparametric statistical tests, such as Run Test, Daniel test, Mann-Kendall test, and Time Series Residual Analysis were applied to analyze the trend in the COD data, Daniel test and Mann-Kendall test indicated upward trend in COD data. The best nonparametric test was suggested to be Daniel test, which is simple in computation and easy to understand the intuitive meaning.

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환경독성 평가를 위한 좀개구리밥(Lemna gibba)의 성장저해시험법에 관한 연구 (Use of Duckweed (Lemna gibba) Growth-Inhibition Test to Evaluate the Toxicity of Chromate in Korea)

  • 김은주;이성규
    • Environmental Analysis Health and Toxicology
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    • 제16권4호
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    • pp.205-209
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    • 2001
  • Lemna gibba was newly cultured and provided for toxicity tests. In this study, the chromate toxicity tests for Lemna gibba were performed according to the OECD Lemna growth inhibition test guideline. The test species was Lemna gibba, and the tests were repeated 5 times. To evaluate the toxicity test results, the average specific growth rate, EC50, 95% confidential limit, and variances were calculated. The test performance was analyzed by the doubling time and test statistics. The average values of EC50 data determined by logistic and linear interpolation curves were 25.9 ppm and 35.4 ppm respectively (by chromate concentration). The doubling time of all controls were below 2.5 day, so all tests passed the criteria for the test performance. This study introduced a new test method, Lemna growth inhibition test, which is provided for the hazard assessment of aquatic environment.

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Behavior, Design, and Modeling of Structural Walls and Coupling Beams - Lessons from Recent Laboratory Tests and Earthquakes

  • Wallace, John W.
    • International Journal of Concrete Structures and Materials
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    • 제6권1호
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    • pp.3-18
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    • 2012
  • Observed wall damage in recent earthquakes in Chile and New Zealand, where modern building codes exist, exceeded expectations. In these earthquakes, structural wall damage included boundary crushing, reinforcement fracture, and global wall buckling. Recent laboratory tests also have demonstrated inadequate performance in some cases, indicating a need to review code provisions, identify shortcomings and make necessary revisions. Current modeling approaches used for slender structural walls adequately capture nonlinear flexural behavior; however, strength loss due to buckling of reinforcement and nonlinear and shear-flexure interaction are not adequately captured. Additional research is needed to address these issues. Recent tests of reinforced concrete coupling beams indicate that diagonally-reinforced beams detailed according to ACI 318-$11^1$ can sustain plastic rotations of about 6% prior to significant strength loss and that relatively simple modeling approaches in commercially available computer programs are capable of capturing the observed responses. Tests of conventionally-reinforced beams indicate less energy dissipation capacity and strength loss at approximately 4% rotation.