• 한국초등과학교육학회지:초등과학교육
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• 제39권3호
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• pp.449-463
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• 2020

This study was to analysis teaching strategies, types of inquiry activities and the relationship between science concepts and inquiry activities presented in science textbooks. As a result of the study, first, the inquiry-based teaching strategies presented in science textbooks were experiment, simulation, demonstration, and field study. Second, there were 53 inquiry activities presented in 8 units related to the earth science area of science textbooks, and the types of inquiry activities were experimental observation (EO) 18, mock activity (SA) 20, investigation discussion and presentation (IP). It was analyzed as 12, data interpretation (ID) 2, and express (EX) 1 piece. Third, the relationship between inquiry activities and science concepts presented in science textbooks was analyzed. As a result of the analysis, out of a total of 42 inquiry activities, 21 inquiry activities corresponded to EA (explicit activities), in which the result of inquiry activities was directly and explicitly linked to science concepts. And IA (implicit activities), which is an implicit inquiry activity in which science concepts must be inferred using the results of inquiry activities, were analyzed as 21. In particular, IA (implicit activities), which is an implicit inquiry activity, can be said to be the result of reflecting the characteristics of earth science areas where many simulated activities (SA) are used. This is considered to be a matter to be considered in the process of developing various elementary science textbooks in the future.

• 전기화학회지
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• 제17권3호
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• pp.179-186
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• 2014

Methanol electro oxidation on the surface of carbon paste modified by $NiCl_2/6H_2O$ was studied in 1M NaOH by potentiostatic and potentiodynamic methods. Ni/C catalyst by the concentration of 5% Ni showed about twice higher electro catalytic activity than Ni metal. The amount of monolayer's on the surface of electrode is almost one order higher for Ni/C than Ni electrode. The kinetic parameters and the diffusion coefficient of methanol were derived from chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) measurements.

• Natural Product Sciences
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• 제22권1호
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• pp.35-40
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• 2016

The first study on chemical constituents and biological activities of Clausena lansium (Lour.) Skeels (Rutaceae) growing in Vietnam has been done. Phytochemical investigation of n-hexane extract led to the isolation of five compounds: dihydroindicolactone (1), 8-geranyloxy psoralen (2), imperatorin (3), heraclenol (4) and indicolactone (5), in which this is the first report on the presence of dihydroindicolactone (1). Their structures were elucidated based on LC/MS/NMR hyphenated techniques as well as comparison with those of literature data. The n-hexane extract and its subfractions, ethanol 95% extract and several isolated compounds were evaluated for antifungal activity.

• 한국과학교육학회지
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• 제30권2호
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• pp.275-290
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• 2010

중학생의 과학탐구활동 수행평가 시 총체적 채점과 분석적 채점의 신뢰도를 비교 분석하였으며, 분석적 채점을 하는 경우에는 신뢰도 확보를 위하여 채점척도의 수준을 어느 정도로 분석적으로 해야 하는지를 조사하였다. 중학생들이 작성한 4개의 과학탐구과제에 대한 활동지를 두 명의 채점자가 총체적 채점 방식, 분석적 채점 방식, 분석적 채점 중 채점척도를 2, 3, 4~7수준으로 다르게 하여 채점하였다. 총체적 채점 방식은 과제 간 내적 일치도가 높게 나타났으며, 분석적 채점 방식은 채점자간 신뢰도가 높게 나타났다. 또한 채점척도 3수준의 경우는 4~7수준의 경우와 활동간 내적 일치도와 채점자간의 신뢰도가 유사하게 나타났으나, 능력추정치별 학생의 분포, 문항곤란도 및 문항특성곡선의 경우 채점척도 3수준의 경우가 적절한 것으로 나타났다. 이러한 연구 결과는 과학탐구활동 수행평가 시 총체적 채점 방식을 선택하는 경우는 과제 간 내적일치도를 높일 수 있으며 분석적 채점 방식에 비해 낮게 나타나는 채점자 간 일치도를 높이기 위한 채점자간 협의등 방안이 필요하다는 것을 시사한다. 또한 분석적 채점 방식을 선택하는 경우는 채점척도 3수준으로 충분히 신뢰도를 확보할 수 있다는 점을 시사한다.

• Advances in Traditional Medicine
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• 제6권3호
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• pp.202-207
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• 2006

The crude methanol extract of the roots of Achyranthes aspera Linn. was investigated for its possible antinociceptive, diuretic and neuropharmacological activities in animal models. At the dose of 250 and 500 mg/kg body weight, the extract showed a significant antinociceptive effect in acetic acid induced-writhing in mice comparable to that produced by diclofenac sodium, used as standard drug. The crude extract produced significant diuretic effect at the dose of 500 mg/kg of body weight comparable to that produced by furosemide, used as standard drug. The extract also potentiated significantly the pentobarbital induced sleeping time in mice; decreased the open field score in open field test, decreased the number of hole crossed from one chamber in the hole cross test and decreased the head dip responses. The obtained results provide a support for the use of this plant in traditional medicine and its further investigation.

• 한국물환경학회지
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• 제33권1호
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• pp.34-39
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• 2017

Under a corrosive environment, electrodes that are applied in the water-treatment system need not only very high electrochemical activity for fast reactions, but also high durability for cost saving. Therefore, the fabrication condition of iridium electrodes was examined to produce a more durable iridium electrode in this study. Tantalum was selected as a binder to enhance the durability of the iridium electrode. Investigation of the weight ratio between the catalyst and the binder to improve electrochemical activity was performed. Also, to compare the effect of the different coating amounts of the catalyst, the results of CV (Cyclic Voltammetry) and EIS (Electrochemical Impedance Spectroscopy) were discussed. Furthermore, an ALT(Accelerated Lifetime Test) was designed and applied to the electrodes to determine the conditions for highly durable electrode fabrication.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 춘계학술대회 논문집
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• pp.567-568
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• 2010

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2000년도 춘계학술대회
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• pp.149-161
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• 2000

This study investigated the management environment of medium and small business by examining the role of medium and small business in national economics, the change in management condition, and the problems in quality and technique. Also we analyzed problems in the past quality control activity of our medium and small business, and examined the driving direction and introduction method of QM. And to understand the effect of manager's concern in quality management to observe the quality system before and after introduction of QM. A target for this investigation is the medium and small business which has introduced QM through ISO 9000.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2003년도 춘계학술대회
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• pp.195-201
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• 2003

This study investigated the management environment of medium and small business by examining the role of medium and small business in national economics, the change in management condition, and the problems in Qualify and technique. Also we analyzed problems in the past quality control activity of our medium and small business, and examined the driving direction and introduction method of QM. And to understand the effect of manager's concern in quality management to observe the quality system before and after introduction of QM. A target for this investigation is the medium and small business which has introduced QM through ISO 9000.

• 한국환경보건학회지
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• 제12권1호
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• pp.25-38
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• 1986

This paper was intented to charily the cause of an increase of serum guanase activity in rats following injection of $CCI_4$. The cause of increasing serum guanase was focused on the change of guanase activities in both serum and liver, and additionally, these results were compared with the previously known alanine aminotransferase (ALT). Concomitantly the microscopic investigation on the histologic changes, and the determination of lipid peroxides of liver were combined in this experiment for a correlation to observe that the activity of guanase would be effected by the various degree of hepatic injury induced by $CCI_4$. The serum levels of guanase were increased about 2 fold in the fatty change stage (3-12 days), 5.2 fold representing the peak value in necrosis stage (21days), 4.5 fold in early cirrhosis stage (48 days), and 2 fold in severe cirrhosis stage (92 days). These changes of serum guanase activity showed similar patterns to those of ALT activity and lipid peroxides in liver cell. The changes of liver guanase activities showed an increase, whereas ALT activities in liver were markedly decreased. It is likely that the increase of serum guanase activity is based on the excess leaking of guanase into blood by the result of accelerated enzyme synthesis in liver cell of $CCI_4$ intoxicated rats. In addition, the possibility could not be ruled out, however, that the increase of serum guanase activity would be caused by the alteration of membrane permeability.