• Korean Journal of Soil Science and Fertilizer
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• v.23 no.1
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• pp.8-14
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• 1990

Retardation and hydrodynamic dispersion coefficient necessary for model of water and solute movement in a soil were determined for horizontal soil column with different initial soil water conditions. The soil columns were compacted with sandy loam soil. The bulk density was $1,350+50kg/m^3$, and initial water contents were 0.05, 0.08 and 0.14. Advancement of 0.05% $CaSO_4$ solution was used as the standard and advancements of 0.5% KCl, $CaCl_2$ and $KH_2PO_4$ were compared. Retardation of non-reactive $Cl^-$ was related with the initial soil water content, ${\theta}n$, as ${\theta}/({\theta}-{\theta}n)$, and anion exclusion was ignored. Retardations of active $K^+$, $Ca^{{+}{+}}$ and $H_2PO_4{^-}$ were related as 1/(R+1) $^*{\theta}/({\theta}-{\theta}n)$, in which R was retardation coefficient. Measured R was 0.64 for $K^+$, 0.80 for $Ca^{{+}{+}}$ and 2.6 for $H_2PO_4{^-}$, respectively. Calculated R using Langmuir adsorption isotherm showed fair degree of applicability. Soil water diffusivity, $D({\theta}),m^2/sec$, calculated for different initial water content showed unique function as $$log(D({\theta}))=13.448{\theta}-9.288$$ Hydrodynamic dispersion coefficient of $Cl^-$ above soil water content 0.36 was similar to soil water diffusivity and decreased to near self diffusion coefficient at soil water content near 0.2. Those of $K^+$, $Ca^{{+}{+}}$ $H_2PO_4{^-}$ at soil water content of 0.38 were $5.5{\times}10^{-6}$, $2.4{\times}10^{-6}$ and $7.1{\times}10^{-7}m^2/sec$ and decreased rapidly with decreasing soil water content lower than 0.36.

• Journal of the Korean Society of Earth Science Education
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• v.13 no.1
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• pp.90-99
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• 2020

The purpose of this study is to investigate the difference in science class ability, science pedagogy achievement and class evaluation factors according to elementary pre-service teacher's gender. Also, the correlation between science pedagogy achievement and science instructional ability was examined. Finally, the evaluation factors applied to the evaluation of science instruction according to male and female gender of elementary pre-service teachers were examined. This study was conducted from september 2019 to december 2019 for 88 elementary pre-service teachers attending P University of Education in Pusan metropolitan city. Among these 88 students, 32 elementary pre-service students were male, 56 were female. The conclusions of this study are as follows. First, as a result of analyzing the science instructional ability according to genders of elementary pre-service teachers, female elementary pre-service teachers showed statistically significant higher scores in science class ability compared to male elementary pre-service teachers. Second, as a result of analyzing the achievement of elementary science pedagogy according to gender of elementary pre-service teachers, female showed statistically significant higher scores for elementary science pedagogy than that of male. Third, as a result of analyzing the correlation between science instructional ability and elementary science pedagogy achievement, there was no statistically significant difference. This result can be applied both side of male and female. Fourth, both male and female pre-service teachers had various instructional evaluation factors, among which the linguistic factors of the instruction were used most frequently as criteria for instructional evaluation.

• Journal of the Mineralogical Society of Korea
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• v.6 no.2
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• pp.57-79
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• 1993

Chuncheon nephrite, which was formed by the polymetasomatic alteration of dolomitic marble, can be classified into pale green, green, dark green, and grey types on the basis of their occurrence, mineralogical and textural characteristics. The nephrites consist obiefly of fibrous or hairlike(length/width ratio>10) cryptocrystalline(crystal width < $2{\mu}m$) tremolite, and include less amounts of micro-crystalline diopside, calcite, clinochlore, and sphene as impurities. The oriented and rather curved crystal aggregate, of nephritic tremolite are densely interwoven, resulting in a massive-fibrous texture which may explain the characteristic toughness of nephritic jade. The characteristic greenish color of the nephrite may be preferably related to Fe rather than Cr and Ni. However, the variation of color and tint in the Chuncheon nephrite also depends on the mineralogical and textural differences such as crystallinity, texture, and impurities. The chemical composition of the nephritic tremolite is not stoichiometric and rather dispersed especially in the abundances of Al, Mg, and Ca. Al content and Mg/Ca ratio for the nephritic tremolite are slightly increased with deepening in greenish color of the nephrite. Fe content in the nephritic tremolite is generally very low, but comparatively richer in the dark green nephrite. In nephritic tremolite, wide-chain pyriboles are irregularly intervened between normal double chains, forming a chain-width disorder. Most nephritic tremolites in the Chuncheon nephrite show various type of chain-width defects such as triple chain(jimthompsonite), quintuple chain (chesterite), or sometimes quadruple chain in HRTEM observations. The degree of chain-width disorder in the nephritic tremolite tends to increase with deepening in greenish color. Triple chain is the most common type, and quadruple chain is rarely observed only in the grey nephrite. The presence of pyribole structure in the nephritic tremolite is closely related to the increase of Al content and Mg/Ca ratio, a rather dispersive chemical composition, a decrease of relative intensity in (001) XRD reflection, and an increase in b axis dimension of unit cell. In addition, the degree and variation of chain-width disorder with nephrite types may support that an increase of metastability was formed by a rapid diffusion of Mg-rich fluid during the nephrite formation.

• Journal of The Korean Association For Science Education
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• v.34 no.5
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• pp.499-510
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• 2014

The purpose of this research is to understand interactive learning during docent-led tours in a science museum focusing on scaffolding. We developed a scaffolding framework by collating the work of other researchers in related fields. The results show that scaffolding included three dimensions: purpose, interaction, and domain. The purpose dimension, divided into six categories, is related to the intention of the scaffolder and what the scaffolding are for: strategic, social, procedural, conceptual, verbal, and metacognitive. The interaction dimension reflects students' interaction with the scaffolder in two ways: dynamic (situation specific) and static (planned in advance). The domain dimension is related to two contents: domain-general and domain-specific (such as science). The scaffolding framework was applied to dynamic interactions between docents and visitors. The data was collected from elementary school students' family visits with the guidance of two docents at the Seodaemun Museum of Natural History. The data collected consisted of surveys, interviews, video-recordings, and transcripts. The analysis shows that five guiding contexts and scaffolding phases were recognized; 1) strategic scaffolding in a poorly illustrated exhibit; 2) conceptual scaffolding in a thoroughly explanative exhibit; 3) verbal scaffolding in misleading interpretation; 4) procedural scaffolding in a manipulative exhibit; and 5) metacognitive scaffolding with inaccurate content. In addition, the results show that the docents used the dynamic and static scaffolding synthetically so that the docent-led tour was effective. In conclusion, this study presents the usefulness of understanding visitors' science learning through the scaffolding framework, as well as the how docents can scaffold actively.

• Journal of Sericultural and Entomological Science
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• v.26 no.2
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• pp.11-15
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• 1984

To save the labour reguired for separation of copulated moth during egg Production, some of the chemicals available at the market were on screen test for easy separation of copulated moth of silkworm. The obtained results are summarized as following. 1. In a separation ratio of copulated moth along with a treating time, TCTFE(Trichloro-trifluoroethane) completely separated the copulated moth in 10 minutes. The combinations of TCTFE plus Acetone (87.5 : 12.5 V/V) and TCTFE plus Acetic acid (50 : 50 V/V) take 25minutes for the complete separation of copulated moth. Use of Acetic acid solution only makes 100% separation of copulated moth in one hour and foully minutes and non$.$treatment shows only 47.5% of separation in three and half hours. On the other hand. There is no statistical significance between TCTFE Plus Acetone and control in the egg productivity. 2. The combination of TCTFE Plus Acetone (87.5 : 12.5 V/V) does not infuluence the egg productivity of the moth, showing 443 grains for an average number of egg per moth out of which 417 grains are for the number of fertilized eggs while control shows 452 grains for an avarage number of egg/moth and 428 grains for the number of fertilized eggs. However a sing1e use of TCTFE and Acetic acid shows less egg productivity and number of ferilized eggs per moth, respectively as compared to those of the control. In particular, a single use of acetic acid makes an increase of number of non-egg prodncible moth and it seems to be brought due to a chemical damage. 3. In a rearing test of the egg laid by the chemical treated moth, there are no differences among the treatments in all of the useful characters of the larvae; larval duration, survival rate, cocoon yield, single cocoon weight, single cocoon shell weight and cocoon shell ratio. In these regards, it is recognized that TCTFE can be practically used for the separation of copulated moth and the combination of TCTFE and Acetone promote its efiectiveness on the separation of copulated moth.

• Journal of the Korean Society of Earth Science Education
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• v.10 no.2
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• pp.104-121
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• 2017

The purpose of this study is to identify the status of the science museum reflected in the exhibition, and develop and apply Nature of Science(NOS) education programs based on the science museum exhibition. The analyse tool was developed to understand the NOS in the science museum. The researchers recognized the nature of science reflected in four exhibition halls in Korea. Based on the analysis, we developed the NOS education program. NOS education programs were developed and applied to supplement the NOS that appears to be limited to scientific exhibitions based on the prior analysis of science exhibition. The results of the study were as follows. First, we analyzed the nature of science reflected in the exhibition of two main science museums, and it was mostly implicit and most were to understand the relationship among STS(Science-Technology-Society). And also we analyzed the NOS reflected in the exhibition of two national history museum, and it was also mostly implicit and most were about the way of how to find out the knowledge, inference. Second, in order to supplement the NOS of the science museum, we developed the NOS education program based on the exhibits. After applying it to the science museum, we conducted a qualitative study. As a result, there was a positive change only in the aspects of NOS (science is tentative, science is from creativity and imaginative, science is the produce of social and culture, science is from the scientific method) that reflected explicitly. The conclusions derived from this study are as follows : For the cultivation of science in the scientific museum, various factors are needed depending on the theme of the science museum. Also, it is helpful to actively implement the NOS educational programs that utilize the exhibit. Therefore, the exhibit planners' and developers' competencies are critical to develop explicit NOS education programs in its expertise.

• Journal of the Korean Society of Food Culture
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• v.6 no.4
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• pp.393-401
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• 1991

In order to compare the food consumption pattern of college girls on weekday and Sunday, the food intake of college girls in a district of Pusan city was analyzed through the factor analysis method. The principal results are as follows. 1. The amount of food intake on Sunday was generally larger than the average values of the food intake on weekday except for soybean & products, meats and beverage. 2. As for correlation coefficients among the intake of each food group, on weekday, positive correlation was noted among rice, potatoes, soybean & products and sea-weeds, fish & shells and fat & oil. And confectionery & sugar showed also a positive correlation to bread, while, on Sunday, vegetables, sea-weeds and meats showed a positive correlation to rice, and other cereals and eggs showed a positive correlation to bread & noodles, too. As for the relationship among rice and bread & noodles, a negative correlation was noted both on weekday and Sunday. 3. As for the factor analysis of the food intake on weekday through the correlation matrix, in the first factor, soybean & products, fat & oil, sea-weeds, rice and fish & shells showed comparatively large factor load, and in the second factor, meats, kimchi, vegetables, soybean & products, fruits and fish & shells showed large factor load. Here the first factor showed the Korean dietary life and the second factor showed subsidiary food (control nutrient) factor. In case of the food intake on Sunday, in the first factor, rice, meats, sea-weeds, soybean & products and vegetables showed large factor load, and in the second factor, fish & shells, vegetables, fat & oil, fruits and rice showed large factor load. Accordingly, the first factor and the second factor were considered to show Korean dietary pattern. 4. Nutrient intake on weekday and Sunday was substantially sufficient to RDA except for energy and iron.

• Magazine of the Korean Society of Agricultural Engineers
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• v.13 no.1
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• pp.2162-2176
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• 1971

From the ancient times our forefathers settled down in this peninsular and cultivated the hills and waste-lands into fields. Instead of fertilizing the lands they moved to find other fertile lands and lived a feudal life of agriculture and various machines played a main role in the land reclamation. The best method of land clearing, the time and efficiency in the operation and the effect of growing crops should sysematically analized prior to the time of 3rd Five-year Economic Development(1972-1976) in order to cultivated 210,000 ha of waste-land or the modernization of our country. The present study was investigated to find out a new working-system of mechanical land clearing and development of fertile soil. The results are as follows: 1) The land reclamation in natural slope is much more encourageable in land clearing and farming when the slope is below ten grades than bench terrace. 2) Weeds were mixed with soil in the land clearing work in order to supply organic materials and to make soil swollen instead of burning of just removing. 3) The equipments such as bulldozers, harrows, power tillers and so on should be prepared in order to do a systematic work in the land clearing. 4) The work of pulling-up roots is dependent upon the forms of roots spreading under the ground. The work of the pulling-up the straight roots was most difficult. 5) The land clearing work of the wrinkled style blocks was easy in pulling up roots and in the time of first plowing. The harrowing work could also be simply done. 6) The amount of soil carried was $240m^3/10a$, 15.6% increased amount from the standard block, while the required time of clearing work was 2 hours 15 minutes 45 seconds/10a, the one third of time required for the standard block. 7) The time disc harrowing work increased 50%, or 15 minutes/10a compared to the harrowing work required in the cultivated soil. 8) The time of rotary tilling increased 2.4 times or 1 hour 47 minutes 43 seconds/10a compared to the time required in the cultivated soil. 9) The reclamed land should be fertilized according to the soil quality, especially added fertilizer should be more than 1,200kg/10a, limes 20kg/10a. In order to produce added fertilizer grass fields should be needed. 10) The experiment of pasture growing is now progressing and therefore the effect of land clearing and the degree of developed soil will be investigated before long.

• Journal of Sasang Constitutional Medicine
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• v.11 no.1
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• pp.201-220
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• 1999

We got these results after studying about modification of Gejitang(桂枝湯) that showed on sympton and prescription about Soumin(少陰人). 1. There are totally eleven prescriptions related to Gejitang appeared on Dongyi-Soose-Bowon(東醫壽世保元). Among them, one is prescription of Danguisayoktang(當歸四逆湯) in prescription of Discussion of Cold Induced Disorder(傷寒論) and another is Gejibujatang(桂枝附子湯) in Won-Myung dynasty period(元明時代). There are nine prescriptions in LeeJae-Ma(李濟馬)'s pre-scription and we can see there are many prescriptions used prescriptions related to Gejitang for Mang Yang(亡陽). 2. Pre-scriptions related to Gejitang has seven prescriptions in Extra-disease(表病證), and two prescriptions in Intra-disease(裏病證) which are analyzed as modified prescription from Gejitang. 3. Although 藿香正氣散, 香蘇散, 芎歸香蘇散, 八物君子湯 etc. are not modified prescriptions of Gejitang, We can see that its are brought up to be on the same with alternative remedy of Gejitang in each step of symptoms. 4. Symptoms are exactly classified in Soumin, the prescription which is used in different symptoms of diseases is similar in raw materials. It's because the remedy of Acending and Descending(升降) is used under the same purpose that maintain Yangnan Qi(陽暖之氣). 5. We could realize that Panax gienseng(人蔘), Cinnamomum Cassia(肉桂) and Aconitum Carrnichali(附子) are commonly important to reinforce Yangnan Qi because the more disease got worse, the more patient lost Yangnan Qi on both Extra-disease and Intra-disease in the Soumin's disease.

• Journal of The Korean Association For Science Education
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• v.34 no.7
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• pp.613-624
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• 2014

The aim of this study is to explore why Korean 4th graders' interest in science was not connected to career aspirations in science using the perspective of science identity. Forty-five students with a high interest in science but with low science-related aspirations have been chosen from 488 elementary school students who have completed a questionnaire exploring students' interest and career aspirations in science. Among them, 19 who have received parental permission participated in in-depth interviews examining students' science identities (interest, competence, and recognition by others in science) and their experiences and perceptions of science-related activities. The results showed that most students have limited or situational interest in science, a gap between the perception of their competence in science and their competence for a science-related career, and negative recognition by others in science. Also, participants' science identities and low aspirations for a science-related career constrained their attention and participation in science-related activities. Students' negative science identities and low aspirations for science-related careers were based on the high standards of science-related careers. It seems that these erroneous perceptions and expectations led them to differentiate themselves from students pursuing science-related careers, as well as to perceive that their interest, competence, and recognition by others in science were not enough to pursue a science-related career. This study has implications for understanding the current condition of young students with low aspirations for science careers and exploring desirable objectives and strategies to promote activities to raise their aspirations for science-related careers.