• Journal of Ecology and Environment
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• v.37 no.2
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• pp.41-51
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• 2014

This study investigated the ability of Bothriochloa bladhii (Retz.) S.T. Blake (Poaceae), Cyperus ligularis L. (Cyperaceae), Commelina erecta L. (Commelinaceae), Mariscus umbellatus (Rottb.) Vahl (Cyperaceae), Fimbistylis miliacea L. (Cyperaceae) and Torulinium odoratum L. (Cyperaceae) to clean up various levels of used motor oil (UMO) contaminated soils. The plants were grown in 2 kg garden soils treated to 0%, 1%, 5% and 10% levels of UMO contamination. The plant growth parameters, chlorophyll contents and dry weight of test plants were measured. The phytoremediation ability of these test plants were assessed by measuring the uptake of hydrocarbons in terms of total hydrocarbon content (THC) as well as their percentage degradation values. There was significant (P < 0.05) reduction in leaf chlorophyll contents and dry weights of the test plant species planted in UMO contaminated soils. THC as well as the percentage uptake (or degradation) of hydrocarbons were both lowest in C. ligularis but highest in T. odoratum in all cases. The phytoremediation potential of test plants was highest in soils contaminated with 5% UMO. Based on the results of this study, all test plants with the exception of C. ligularis were potentially capable of undertaking phytoremediation. However, B. bladhii and T. odoratum proved most effective in the uptake and degradation of UMO.

• Communications for Statistical Applications and Methods
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• v.16 no.4
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• pp.615-625
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• 2009

In this paper we describe Wilcoxon test and T-test that are well-known in two-sample location problem for detecting edges under different window configurations. The choice of window configurations is an important factor in determining the performance and the expense of edge detectors. Our edge detectors are based on testing the mean values of local neighborhoods obtained under the edge model using an edge-height parameter. We compare three window configurations based on statistical tests in terms of qualitative measures with the edge maps and objective, quantitative measures as well as CPU time for detecting edge.

• Economic and Environmental Geology
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• v.36 no.1
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• pp.49-58
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• 2003

To analyze the anisotropic characteristics of fractured aquifer, variations of streaming potential were measured during and after pumping over several wells at the two test sites. Surface electrical resistivity survey, normal resistivity logging, and slug test were performed at the wells to identify the hydrogeological structure. Applying the results to the recently suggested model, the aquifer of the two test sites showed confined characteristics. Anisotropic direction appeared in using equi-potential maps from self-potential monitoring results matched well with the results of the hydrogeological test. The self-potential monitoring method adopted in this study would be useful for providing a more reliable information on the anisotropy of aquifer in the pumping test at single well.

• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.1
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• pp.81-89
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• 1995

The aim of the work described in this paper is to develope a constitutive model for the prediction of an unsaturated Soil and to confirm the application of the model, which is composed of the elastic and plastic part in consideration of the matric suction and the net mean stress. From test results, volume changes and deviator stresses are analyzed at each state and their relationships are formulated. And the application of the model to silty sands is con- firmed by the comparison between test and predicted results. During drying-wetting and loading-unloading processes for isotropic states, the agreement between predicted and test results are satisfactory. And predicted deviator stresses are well agreed with test results in shearing process. Overall acceptable predictions are reproduced in high confining pressure. Usefulness of the model is confirmed for the unsat- urated soil except volumetric strain, which is not well agreed with the test results due to deficiency of dilatancy of the model in low confining pressure. It is, therefore, recom- mended to study the behavior of dilatancy for an unsaturated soil.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 1993.11a
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• pp.2-2
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• 1993

The present status of the thennomechanica1 evaluation of functionally gradient materials(FGMs) for space plane application was reviewed, in which research activities and the cooperation of the national project team organized to study FGM science were demonstrated. The project team was divided into three working groups; de singing, processing and evaluation, each of which had their own tasks in the project cooperation. The testings details of the various thennomechanical tests for the FGM samples fabricated by the processing groups were described, along with their corresponding heating conditions of the real environments in the space plane application. For small-sized samples, laser beam heating test and burner heating test were well applied to study the heat shielding and heat resisting properties. Arc-heated wind tunnel test and high temperature!high velocity gas flow test were used for large-sized panel assemblies having cooling structures. The criteria for the evaluation of the heat shielding and heat resisting properties of the FGMs, as well as a crack activation mechanism in their differential temperature heating, were proposed on the basis of the observation in the burner heating test.

• Journal of The Korean Association For Science Education
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• v.11 no.1
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• pp.59-72
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• 1991

This study has formed a clear definition of the elements of inquiry skills : inference, determining relationship, causal explanation, prediction, and created the goals of assessment and the items of assessment. They have been checked the validity and the objectivity and the clarity of the items by six professors of science education. At the same time, the two times of the field trial has been executed. and checked the discriminating power and the difficulty index and the effectiveness of distracters, and modified the items. The test developed in this way was administered to 1060 students of the eighth grade, randomly cluster-sampled from the universe, and standardized. The test is the aptitude test as well as the norm-reference test. and has twenty items. The testing-time is thirty minutes. And the cotent validity is 85%, the objectivity of the answer keys 91.7%, the mean of items difficulty 68.8%, the mean of discriminating power 0.39, the standard deviation 3.31, the reliability(K-R 20) 0.69. Because it is the standardized lest, it can diagnose the well-developed skills and the ill-developed skills of the students, and monitor the development of skills.

• Magazine of the Korean Society of Agricultural Engineers
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• v.38 no.3
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• pp.101-110
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• 1996

The aim of the work described in this paper is to develope a constitutive model for the prediction of an unsaturated clayey soil and to confirm the application of the model. To this end a series of suction controlled isotropic and triaxial compression tests are conducted on clayey soils. Matric suction is controlled by the axis translation technique using high air entry ceramic disk. Total volume change, air and water volume changes are measured by the device made for the experiment. The specimens are compacted by dynamic compaction using a half of Proctor compaction energy with the water contents of 5% drier than the optimum moisture contents. From test results, volume changes and deviator stresses are analyzed at each state and their relationships are formulated. And the application of the model to clayey soils is confirmed by the comparison between test and predicted results. During drying-wetting and loading-unloading processes for isotropic states, the agreement between predicted and test results are satisfactory. And predicted deviator stresses are well agreed with the test results in shearing process, but volumetric strain is not well agreed with the test results in high suctions.

• Korean Journal of Oriental Medicine
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• v.7 no.1
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• pp.85-103
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• 2001

Objectives : Assuming that the characteristic of meridian system has been similar to this of electric potentials in human body and that measurements of electric potential at well(井穴) and sea(合穴) points in branches of the twelves meridians will be representative of measurements of the twelve meridians, to measure the electric potentials in twenty aged(TAG) and fifty aged(FAG) healthy volunteers groups when they were sleeping or awakening respectively, to do significance test for electric potential of meridian system among circadian rhythms(CR) and Sasang constitutions(SC). Methods : We selected who thirty healthy volunteers were diagnosed by a blood test, urine examination and differentiation of syndromes by five viscera among volunteers. When they were sleeping, their electric potentials of well and sea points in branches of the twelve meridians were simultaneously measured by physiograph. After a minute we measured them again, totally 5 times. And then when they were awakening, their electric potentials were measured 5 times by the above method. Results : Measurements were analyzed by statistical ANOVA test, we obtained that some of the electric potentials of TAG at sleeping significantly varied with CR, SC, and at awakening some of the electric potentials of FAG also significantly did with CR, SC.

• English Language & Literature Teaching
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• v.9 no.1
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• pp.153-171
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• 2003

The scores of TOEFL, TOEIC, and TEPS have been increasingly used for many purposes in Korea. In particular, these test scores are being used as a predictor for determining readiness for and success in college work, or as a measure of the testees' overall English proficiency. Nonetheless, studies have rarely proposed that the validity of the test scores is used for either purpose. As a preliminary step to explore the predictive validity of the test scores, we collected the scores of TOEFL, TOEIC, and TEPS from thirty students of a university as well as their cumulative grade point averages (GPAs). The correlations between the test scores and GPAs show that TOEFL will be most likely to have the highest validity coefficient as a predictor for determining success in college work as well as a measure of overall English proficiency. Although this study has a few limitations such as the small number of participants, their homogeneousness as a group, etc., it provides some insight into the use of the three tests for college admissions and measurement of overall English proficiency and suggests need for conducting further validation studies in these areas.

• Geomechanics and Engineering
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• v.13 no.6
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• pp.1027-1044
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• 2017

Membrane penetration is the most important factor influencing the measurement of volume change for triaxial consolidated-drained shear test for coarse-grained soil. The effective pressure p, average particle size $d_{50}$, thickness $t_m$ and elastic modulus $E_m$ of membrane, contact area between membrane and soil $A_m$ as well as the initial void ratio e are the major factors influencing membrane penetration. According to the membrane deformation model given by Kramer and Sivaneswaran, an analytical solution of the membrane penetration considering the initial void ratio is deduced using the energy conservation law. The basic equations from theory of plates and shells and the elastic mechanics are employed during the derivation. To verify the presented solution, isotropic consolidation tests of a coarse-grained soil are performed by using the method of embedding different diameter of iron rods in the triaxial samples, and volume changes due to membrane penetration are obtained. The predictions from presented solution and previous analytical solutions are compared with the test results. It is found that the prediction from presented analytical solution agrees well with the test results.