• Title/Summary/Keyword: Preliminary experiment

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A Study on the Bibliotherapy Program's Influence on the Improvement of a Junior High School Student's Career Maturity Degree (독서치료 프로그램이 중학생의 진로성숙도 향상에 미치는 영향에 관한 연구)

  • Lee, Sang-Ae;Cho, Hyun-Yang
    • Journal of Korean Library and Information Science Society
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    • v.38 no.2
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    • pp.101-124
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    • 2007
  • The purpose of the study is to see how the bibliotherapy program has an effect on the improvement of a junior high school student's career maturity degree, and how it can be applied to students for developmental and collective approach. In this experiment, bibliotherapy program was progressed 11 times for 60 minutes to twenty second grade students of W junior high school in Kyeonggi-Do. There are two groups: one is the control group, and the other experiment group. In order to verify the effect of a bibliotherapy program a correspondence specimen t-test analysis was used. The degree of youth's course maturity has been checked to see if there is any difference between the preliminary inspection and the post inspection for both the experiment group and the control group. Moreover, ANCOVA was applied in order to grasp if there is any difference between the experiment group and the control group to the post mark.

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Healing and preventive effects of low-esterified pectin on liver injury induced by carbon tetrachloride in rats

  • Khotimchenko, Yuri S.;Kolenchenko, Elena A.;Khotimchenko, Maxim Y.;Kovalev, Valeri V.
    • Advances in Traditional Medicine
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    • v.4 no.1
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    • pp.28-36
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    • 2004
  • The purpose of this study was to investigate the pharmacological effects of low-esterified pectin on carbon tetrachloride $(CCL_4)-induced$ hepatotoxicity in rats. The study included two experiments. In the first experiment the animals were given daily $CCL_4$ through gavage for 7 days and then 10, 50, or 250 mg/kg b.w. of pectin for 21 days. At the end of experiment rats were killed within 24 hours. The increased bilirubin level, enhanced alanine aminotransferase and aspartate aminotransferase activity in plasma induced by $CCL_4$ were partly normalized by pectin administration in a dose-dependent manner. The pectin treatment also resulted in significant recovery of $CCL_4-induced$ decrease of the liver glycogen content. In addition, pectin significantly improved $CCL_4-induced$ alterations of pro-oxidant and antioxidant biochemical parameters in liver and plasma compared to those of rats administered $CCL_4$. In the second experiment the animals were given daily 10, 50 or 250 mg/ kg b.w. of pectin for 21 days before a 7-day administration of $CCL_4$. Rats were killed 24 hours after the end of experiment. Pretreatment with pectin before $CCL_4$ administration resulted in significantly inhibited increase of the blood enzymatic activities of alanine and aspartate aminotransferases and bilirubin level in a dose-dependent manner. Also, preliminary administration of pectin prevented elevation of malondialdehyde and conjugated diene levels in liver and plasma as well as a reduction of glutathione content in liver of rats given $CCL_4$. These results suggest that low-esterified pectin exert healing and preventive effects on $CCL_4-induced$ hepatotoxicity in rats.

Development of a Moldboard Plow to Invert Furrow Slice at the Same Position (토양의 제자리 반전을 위한 몰드보드 플라우의 개발)

  • 이규승;박원엽;권병기
    • Journal of Biosystems Engineering
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    • v.29 no.1
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    • pp.9-20
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    • 2004
  • On the basis of design theory of soil inversion, two types of moldboard plow with secondary soil mover was designed and constructed to invert furrow slice at same position with furrow bottom. A series of soil bin experiment was carried to investigate the performance of prototypes. First prototype of new concept plow showed two kinds of problems during the preliminary experiment. For the plowing depth of 6cut the prototype did not invert the furrow slice, instead it just cut furrow bottom and the furrow slice returned to the original position. For the plowing depth of 8cm, there was soil clogging problem at the rear part of plow. From the above results it was concluded that the first prototype can not be used for the inversion of furrow slice at same position with furrow bottom. Second prototype could invert furrow slice at the same position with furrow bottom, but the performance was affected by soil moisture content soil hardness and plowing speed very much. For the higher soil moisture content, for the higher soil hardness and higher plowing speed, the prototype showed higher soil inversion performance. For the second prototype the inversion ratio was almost 100%, inversion angle was in the range of 90 to 100 degree and side displacement was less than 4 cm. But the furrow slice was not continuous, it was cut in the length of 30 to 40 cm. The reason why the furrow slice was cut in that length is blamed for the design of moldboard surface. The specific draft of prototype was in the range of 37.24 kN/㎡ to 42.14 kN/㎡ this value is a little higher than that of the conventional plow, or from 30.38 kN/㎡ to 33.32 kN/㎡. But the difference was not so big. The inversion performance of the second prototype for the field experiment was much better than that of soil bin experiment due to the better soil and operational conditions. Sticky and compacted soil conditions, and higher plowing speed was suitable for the plowing operation of the second prototype

A Preliminary Conductivity Model Experiment for Determining Hydraulic Constants in Physical Model Borehole (시추공 수리전도도 상수를 결정하기 위한 전기전도도검층 기법을 이용한 예비모형실험)

  • 김영화;임헌태
    • Journal of Soil and Groundwater Environment
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    • v.8 no.1
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    • pp.48-56
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    • 2003
  • A geophysical conductivity logging technique has been adopted to determine hydraulic constants using a simplified physical model that depicts the borehole condition. An experiment has been made by monitoring the conductivity change within the model hole using borehole environment water and incoming-outgoing water of different salinity, under the state of constant flow rate by maintaining balance between inflow and outflow. Conductivity variation features were observed that depended on flow rate, salinity contrasts between fluid within the hole and incoming-outgoing fluid, and density contrasts between fluid conductivity within the hole and incoming fluid. The results of the experiment show the uniform change of fluid conductivity within the hole with time, a fairly good correlation between the flow rate and the conductivity change rate. The geophysical conductivity logging technique can be an efficient tool for determining hydraulic constants if the model equation is verified by henceforward experiments.

Classification of Multi-temporal SAR Data by Using Data Transform Based Features and Multiple Classifiers (자료변환 기반 특징과 다중 분류자를 이용한 다중시기 SAR자료의 분류)

  • Yoo, Hee Young;Park, No-Wook;Hong, Sukyoung;Lee, Kyungdo;Kim, Yeseul
    • Korean Journal of Remote Sensing
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    • v.31 no.3
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    • pp.205-214
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    • 2015
  • In this study, a novel land-cover classification framework for multi-temporal SAR data is presented that can combine multiple features extracted through data transforms and multiple classifiers. At first, data transforms using principle component analysis (PCA) and 3D wavelet transform are applied to multi-temporal SAR dataset for extracting new features which were different from original dataset. Then, three different classifiers including maximum likelihood classifier (MLC), neural network (NN) and support vector machine (SVM) are applied to three different dataset including data transform based features and original backscattering coefficients, and as a result, the diverse preliminary classification results are generated. These results are combined via a majority voting rule to generate a final classification result. From an experiment with a multi-temporal ENVISAT ASAR dataset, every preliminary classification result showed very different classification accuracy according to the used feature and classifier. The final classification result combining nine preliminary classification results showed the best classification accuracy because each preliminary classification result provided complementary information on land-covers. The improvement of classification accuracy in this study was mainly attributed to the diversity from combining not only different features based on data transforms, but also different classifiers. Therefore, the land-cover classification framework presented in this study would be effectively applied to the classification of multi-temporal SAR data and also be extended to multi-sensor remote sensing data fusion.

EFL College Students' Perceptions toward the Use of Electronic Dictionaries

  • Park, Mae-Ran
    • English Language & Literature Teaching
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    • v.12 no.1
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    • pp.29-54
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    • 2006
  • The purpose of this study is two-fold: first, to examine the current status of e-dictionary use in Korea and the attitude toward its use by Korean college students; second, to investigate to what degree e-dictionaries may be useful and effective tools in helping to improve learners' overall English skills. The subjects were 84 college students and they were divided into two groups: the experiment group and the control group. The instrument employed was the Preliminary Student Usage Questionnaire, which was developed by the researcher, together with the questionnaire survey developed by Koyama and Takeuchi (2004), which was modified for the study. The findings from this research are as follows: First, a special instruction session on how to use e-dictionaries made a statistically significant difference among users of the dictionaries. Those subjects who had received the instruction displayed a more positive attitude toward the use of e-dictionaries. Second, the experiment group showed a more favorable attitude toward the use of e-dictionaries. On the basis of the above results, the researcher suggests that proper guidance on the use of e-dictionaries and their benefits should have a positive influence on users. The findings from the current research will shed light on the current status of electronic dictionary use among Korean college students.

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Experimental Study of Gasification Characteristics of Low-rank Liquid Fuel and Producer gas Generation in a Fluidized Bed Reactor (유동층 반응기에서 액상의 저급 연료 가스화 특성 실험 및 프로듀서 가스 생산을 위한 연구)

  • Kim, Youngdoo;Jeong, Soohwa;Jung, Jaeyong;Yang, Won;Lee, Uendo
    • 한국연소학회:학술대회논문집
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    • 2014.11a
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    • pp.25-28
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    • 2014
  • In this study, waste cooking oil was gasified in a fluidized bed reactor. The main objective of this study was to produce clean producer gas for power generation engine. As a result, heating value of producer gas is suitable for engine operation and tar content in producer gas was satisfied after use of activated carbon filter. Results from a lab scale experiment and a preliminary results from a pilot scale experiment will be presented.

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Short Circuit Tests of the Three-Phase DC Reactor Type Fault Current Limiter in Changing of Turns Ratio of Transformers (변압기 권선비의 변화에 따른 3상 DC 리액터형태 한류기의 단락실험)

  • Lee, Eung-Ro;Lee, Chan-Ju;Lee, Seung-Je;Go, Tae-Guk;Hyeon, Ok-Bae
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.51 no.6
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    • pp.267-272
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    • 2002
  • This Paper deals with the short circuit tests of the three-Phase DC reactor type fault current limiter (FCL) in changing of turns ratio of transformers. The experiment of this paper is a preliminary step to develop the FCL's faculties for an application to high voltage transmission line. So, superconducting coil was made of Nb-Ti, low temperature superconductor, and the ratings of the power system of experimental circuit are 400V/7A class. A three-phase DC reactor type FCL consists of three transformers, six diodes, one superconducting coil and one cryostat. The important point of experimental analysis is transient period, the operating lagging time of circuit breaker. As the results of the experiment, the values are referred to the limitation rate about 77% and 90% when the turns ratio of transformer was 1:1 and 2:1 respectively.

A Preliminary Study comparing the Growth of Phytoplankton according to the Ratio of Deep and Surface Seawater (해양심층수와 표층수의 혼합비율에 따른 식물플랑크톤의 증식 변화에 대한 기초연구)

  • Kim, Ah-Ree;Lee, Seung-Won;Jung, Dong-Ho;Moon, Deok-Soo;Kim, Hyeon-Ju
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.43 no.4
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    • pp.373-379
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    • 2010
  • The artificial upwelling of deep seawater increases primary production. This study conducted a lab-scale experiment to investigate the growth of phytoplankton with the mixing ratio of deep and surface seawater. The chlorophyll content in the sample of pure deep seawater was highest, regardless of the phytoplankton groups. Nutrients contained in the deep seawater positively influenced the growth of phytoplankton. The optimum mixture to apply in an artificial upwelling system was a 1:1 ratio of deep and surface seawater. An experiment considering other environmental conditions, such as luminance and specific gravity, should be performed.

Research on Damping Characteristics of a Helmholtz Resonator using a Rijke Tube (Rijke tube를 이용한 열유동 환경하에서의 음향공 감쇠 특성 연구)

  • Kim, Geun-Cheol;Jeon, Jun-Su;Kim, Jai-Ho;Ko, Young-Sung;Kim, Hong-Jip;Kim, Young-Moon
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2011.11a
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    • pp.873-876
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    • 2011
  • In this research, a Helmholtz resonator was applied to the thermo-acoustic environment that has thermal gradient using Rijke tube. The thermo-acoustic instability was invoked by a Rijke tube which use a DC power supplier and a Blower. A target instability frequency was appeared by the Rijke tube. A preliminary experiment on damping characteristics of the resonator in the thermo-acoustic environment was performed and compared with the room temperature experiment data.

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