• Title/Summary/Keyword: environmental test

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Effects of Environmental Reinforcement Through Motivation on Motor and Cognitive Function in Rats With Focal Ischemic Brain Injury

  • Heo, Myoung
    • Physical Therapy Korea
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    • v.16 no.4
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    • pp.44-52
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    • 2009
  • It is known that individual factors as cognitive, perception, emotion, and motivation may greatly influence on recovery from neurologic region. This study was to investigate the effects of environmental reinforcement through motivation to perform the tasks voluntarily on motor and cognition function in rats with focal ischemic brain injury. Focal ischemic brain injury was induced in Sprague-Dawley rats (15 rats, $250{\pm}50$ g) through middle cerebral artery occlusion (MCAo). And then, experiment groups were randomly divided into three groups; The control group: MCAo induction ($n_1$=5), the environmental reinforcement (ER) group: the application for ER after MCAo induction ($n_2$=5), the environmental reinforcement through motivation (ERM) group: the application for ERM after MCAo induction ($n_3$=5). The climbing test (CT) and the modified limb placing tests (MLPTs) to measure the motor function and the Morris water maze acquisition test (MWMAT) and the Morris water maze retention test (MWMRT) to measure the cognitive function were performed. For the CT, the ERM group was significantly larger than the ER group. For the MLPTs, the ERM group was significantly decreased compared to other groups. For the MWMAT, the time to find the circular platform in the ERM group significantly decreased compared to other groups. For the MWMRT, the time to dwell on the quadrant circular platform in the ERM group was significantly increased compared to other groups. These results suggested that the ERM could improve the motor and cognitive functions in the rats with focal ischemic brain injury.

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Evaluation of Behaviors on Mooring Line Embedded in Sand Using Centrifuge Test (원심모형실험을 이용한 모래지반에 관입된 계류선 거동 평가)

  • Lee, Hoon Yong;Kim, Surin;Kim, Jaehyun;Kim, Dong-Soo;Choo, Yun Wook;Kwo, Osoon
    • Journal of Ocean Engineering and Technology
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    • v.28 no.1
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    • pp.47-54
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    • 2014
  • When an anchor penetrates and is installed under a seabed, a portion of the mooring line connected to the anchor is also embedded under the seabed. This embedded mooring line affects the capacity of the anchor in two ways. First, the frictional resistance that occurs between the mooring line and the seabed reduces the pulling force acting on the anchor. Second, the embedded part of the mooring line forms a reverse catenary shape due to the bearing resistance of the soil, so that an inclined pulling force is applied to the anchor. To evaluate the mooring line's effect on the capacity of an anchor in sand, centrifuge model tests were performed using two relative sand densities of 76% and 51% while changing the anchor depths. The test results showed that the load is reduced much more in deep and dense sand, and the inclination angle of the load is lower in shallow and loose sand.

Use of Chinese Bleak, Aphyocypris chinensis, in Embryo and Sac-Fry Stages Toxicity Test (왜몰개 (Aphyocypris chinensis)를 이용한 Embyo, Sac-fry stages Toxicity Test)

  • Yeom, Dong-Hyuk;Seo, Jin-Won;Lee, Sung-Kyu
    • Environmental Analysis Health and Toxicology
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    • v.20 no.4 s.51
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    • pp.359-363
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    • 2005
  • ESS (Embryo and sac-try stage) 독성 시험에서 시험어종으로서의 국내토착종인 왜몰개 (Aphyocypris chinensis)의 적용성을 평가하기 위하여 아연(Zn)을 사용하여 국제적인 추천시험 어종인 송사리(Oryzais latipes)와 감수성을 비교하였다. 시험기간은 대조군에서 아사가 관찰되는 시기 즉, 왜몰개는 수정 후 8일, 송사리는 수정 후 16일로 하였으며, 시험기간 동안 수정란의 부화율, 수정란 및 난황단계의 치어(sar-fry)의 사망률, 형태적인 발달, 치어의 성장 등을 관찰 및 측정하였다. 두 종 모두 수정란의 생존율에 아연의 영향을 받았으며, LOEC는 모두 14.5 mg/L이었다 난황단계 치어의 사망률을 관찰한 결과, 왜몰개는 1.4mg/L부터 급격히 증가된 반면에 송사리는 14.5mg/L에서 $100\%$사망률이 관찰되었다. 시험물질에 노출된 왜몰개와 송사리 모두 척추변형이 관찰되었으며, 체장을 측정한 결과는 왜몰개가 송사리에 비해 민감하게 반응하는 것으로 나타났다. 위와 같은 결과들은 종합해 볼 때, ESS독성시험에서 왜몰개가 대체 시험어종으로서 사용될 수 있는 가능성을 보여주었다

A Study on Correlations for Void Ratio, Coefficient of Uniformity and Coefficient of Curvature for Determination of Relative Density for Sands

  • Im, Soyeong;Jin, Yongguo;Chun, Byungsik
    • Journal of the Korean GEO-environmental Society
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    • v.14 no.3
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    • pp.13-17
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    • 2013
  • Determination of geotechnical characteristics of soil is either to use the field samples to measure the characteristics of soil through laboratory test or measuring the characteristics directly in the field. Field test can be derived similar value by considering characteristics of site and laboratory test can be confirmed the characteristic of soil by testing with field samples. This article describes relative density as the measure of compaction for cohesionless soils and presents several simple and mathematical relationships to help engineers estimate needed parameters for relative density calculations. The main purpose of this research is to investigate possible correlations between coefficient of uniformity, coefficient of curvature, maximum and minimum void ratio, mean grain size. Results show a linear relationship between the minimum and maximum void ratios and a power function relationship between coefficient of uniformity and the limiting void ratios. Void ratio range, which is the difference between the maximum and minimum void ratios, appeared to be log normally distributed but showed no simple mathematical fit to the data. these results were shown to help engineers estimate needed parameters for relative density calculations.

Estimating the lateral profile of helical piles using modified p-y springs

  • Hyeong-Joo Kim;Hyeong-Soo Kim;Peter Rey Dinoy;James Vincent Reyes;Yeong-Seong Jeong;Jun-Yong Park;Kevin Bagas Arifki Mawuntu
    • Geomechanics and Engineering
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    • v.35 no.1
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    • pp.1-11
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    • 2023
  • A growing trend of utilizing helical piles for soft soil strata to support infrastructure projects is currently observed in Saemangeum, South Korea. Recognized mainly due to its ease of installation and reusability proves to be far more superior compared to other foundation types in terms of sustainability. This study applies modified p-y springs to characterize the behavior of a laterally loaded helical pile with a shaft diameter of 89.1 mm affixed with 3 helices evenly spaced along its embedded length of 2.5 m. Geotechnical soil properties are correlated from CPT data near the test bed vicinity and strain gauges mounted on the shaft surface. A modification factor is applied on the p-y springs to adjust the simulated data and match it to the bending moment, soil resistance and deflection values from the strain gauge measurements. The predicted lateral behavior of the helical pile through the numerical analysis method shows fairly good agreement to the recorded field test results.

The Status and Analysis of PV Module's Certificate (결정질 태양전지모듈 인증시험 현황 및 분석)

  • Kim, Kyung-Soo;Kang, Gi-Hwan;Yu, Gwon-Jong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.55-55
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    • 2009
  • In this paper, we introduce the status of certificate test on crystalline silicon photovoltaic, module in Korea. Up to 5. 2009, about 200 models have passed certificate test under KS C IEC61215 standard. Most products are from Korea, Japan, China. And some are from USA, German and Taiwan. A few environmental test items' results and standard test methods will be discussed. The detail discussion will be shown in the following paper.

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The evaluation of combustion characteristics for 2 kinds of Indonesian sub-bituminous coals by using combustion test facility at KEPRI (시험연소로를 이용한 인도네시아산 아역청탄 2종의 연소특성 평가)

  • Lee, Hyun-Dong;Kim, Sung-Chul;Kim, Jong-Jin;Kim, Tae-Heung;Yang, Seung-Han;Shin, Young-Jin;Min, Chang-Gi
    • 한국연소학회:학술대회논문집
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    • 1999.10a
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    • pp.27-46
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    • 1999
  • Combustion test on two kinds of Indonesian sub-bituminous coals of single and blended with bituminous coal imported for power generation was carried out by using the test furnace at KEPRI. The main items of combustion test were temperature profiles of the inside furnace, the yield of unburned carbon, environmental pollution emissions, slagging/fouling tendency, and the comparison of heat loss of furnace. The test results showed that low sulfur and ash content characterized by the Indonesian coals were advantageous to environmental aspect, but high tendency of heat loss and slagging/fouling were disadvantageous to boiler operation. From the results, the necessity of proper coal blending to compensate these weak points was recommended.

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Teratological test of pesticide using medaka embryo (송사리 태아를 이용한 농약기형독성에 관한 연구)

  • 성하정;이해근;정영호;조명행
    • Environmental Mutagens and Carcinogens
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    • v.16 no.1
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    • pp.30-34
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    • 1996
  • This study was performed to examine the availability of using medaka (Oryzias latipes) in teratological test. Medaka embryos were collected within 2 hours post-fertilization and cultured in petri dishes containing buffered saline until hatching. The embryos were treated with 0.56 mg/l chlorpyrifos-methyl and 10 mM methyl methanesulfonate at 20 stages (about 35 hours post-fertilization). Eleven developmental features were selected and observed from 33 stages (about 9 days post-fertilization). Scoring system was developed and applicated for the measurement of potential teratological effects by the test compound. Chlorpyrifos-methyl did not induce teratological effect in medaka embryos. However, we found teratological test using medaka embryo reduced the cost, labors, period and space of experiment significantly compared with teratological study using rodents. Above findings strongly suggest that medaka embryo can be used as a lab animal model for teratogenicity test instead of rodents.

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Application of Weibull Distribution Function to Analysis of Breakthrough Curves from Push Pull Tracer Test

  • Hyun-Tae, Hwang;Lee, Kang-Kun
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2003.04a
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    • pp.217-220
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    • 2003
  • In the case of the remediation studies, push pull test is a more time and cost effective mettled than multi-well tracer test. It also gives Just as much or more information than the traditionally used methods. But the data analysis for the hydraulic parameters, there have been some defections such as underestimation of dispersivity, requirement for effective porosity, and calculation of recovery of center of mass to estimate linear velocity. In this research, Weibull distribution function is proposed to estimate the center of mass of breakthrough curve for Push pull test. The hydraulic parameter estimation using Weibull function showed more exact values of center of mass than those of exponential regression for field test data.

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Analysis of Environmental Friendly Attitude and Environmental Knowledge on Pre-service Elementary Teacher (초등학교 예비교사의 환경친화적 태도와 환경지식 분석)

  • Lee, Yong-Seob;Kim, Soon-Shik
    • Journal of the Korean Society of Earth Science Education
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    • v.6 no.3
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    • pp.235-241
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    • 2013
  • The purpose of this study is to find out eco-friendly attitude and level of knowledge about environment of pre-service elementary teachers and find relationship between these. In this study, we investigate and analyse with surveys about eco-friendly attitudes and environmental knowledge questionnaire targeting the 2nd semester of 2013 32 people of fast stream class 2nd grade. Also, we analyzed correlation between environmental knowledge and the test results of eco-friendly attitudes. Results for the analysis are as follows. First, pre-service elementary teachers' average of eco-friendly attitudes test result is 'cognitive area(60.22)> definitional area(53.69)> behavioral area(52.72)'. These results are re-service elementary teachers are knowledgeable about the environment, but they are passive at the execution act about environment. Second, the average of pre-service elementary teachers' environmental knowledge result is the highest to the protect the environment, for the average(26.25). It is interpreted that they acquired the most the knowledge related to the conservation of the environment. Third, It is no significant correlation between pre-service elementary teachers' eco-friendly attitudes and environmental knowledge. It means that although they acquired a lot of knowledge related to the environment, it is not affected to environmental friendly attitude putting ideas into action about environment.