• The Korean Journal of Ecology
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• v.10 no.1
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• pp.7-16
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• 1987

The content of Pb and Cd in the soil, producer, 1st consumer and 2nd consumer by the distance from two highway with different construction years and traffic volumes was measured from 1984 through 1986. The result was compared with that of a control in Yangsu-ri near Mt. Unak, Namyangju-gun, Kyunggi-do. The producers in the area of Yangjae-done are composed of 27 species of floras with Glycine soja being the dominant species while those in Shingal 20 species, with Leesia japonica being the dominant species. The faunas in the former area include 37 families and 69 species, with insects being dominant. In the area of Yangjae-dong, the biomass by trophic levels increased from the ration of 1/400 between producer and 1st consumer to the ratio of 1/10 between 1st consumer and 2nd consumer. The Pb content of soil, producer, 1st consumer and 2nd consumer in Yangjae-done near the Kyungbu highway with traffic jam has the sigingacant difference of 1% level at the vicinity of 10 meters and it is the same with that of Shingal area nearthe Youngdong highway with relatively sparse traffic except for the 2nd consumer. In case of cadmium content, the 1st and 2nd consumer has 1% signigicant difference near the Kyungbu highway and other trophic levels have no diference. Besides, the content of Pb and Cd at the site 1, 2 and 3 within the range of 100 meters from the two highways has 1% significant difference from that of a control while the site 4 has no difference.

• Proceedings of the Korean Society of Crop Science Conference
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• 2019.04a
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• pp.132-132
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• 2019

• Journal of Biosystems Engineering
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• v.28 no.1
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• pp.1-10
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• 2003

A computer simulation was carried out to determinate the optimum capacity of bulk type trailer which is used as a tractor attachment. Soil physical properties. such as soil moisture content. bulk density, soil hardness and soil texture were measured in the 10 major rice production area for computer simulation. Mathematical model which include soil physical properties and vehicle factor was used for computer simulation. Most of the soil texture of the investigated area was silty loam. Soil moisture content ranged between 30 and 40% mostly. Soil bulk density was in the range of 1.500 to 1.700 kg/㎥. Soil hardness ranged between 1 to 18 kg/$\textrm{cm}^2$. Soil hardness incorporate the effects of many soil physical properties such as moisture content texture and bulk density, and so the range of soil hardness was greater than any other physical properties. The capacity of bulk type trailer was above 3000 kg$_{f}$ fer the most of the investigated area. and mostly in the range of 4000 to 6000 kg$_{f}$ depending upon the slip. But for the soft soil area such as Andong and Namyang. tractor itself had mobility problem and showed minus trailer capacity for some places. For this area. the capacity of bulk type trailer ranged between 1000 and 2000 kg$_{f}$ mostly so bulk type trailer should be designed as a small capacity compared to the other area.ared to the other area. area.

• Applied Chemistry for Engineering
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• v.5 no.5
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• pp.878-888
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• 1994

In order to investigate the fracture behavior of ABS terpolymer under the tension and impact load, varing the content of rubber, molecular weight of SAN, content and kinds of lubricant, tension speed, the mechanical properties were measured and SEM pictures of fracture area were taken. Under the tension, the tensile strength increased as rubber content and lubricant content decreased, while molecular weight and tension speed increased. The deformation of area near fracture site did not occur as rubber content, tension speed and molecular weight decreased and liquid lubricant was used. And in the shape of fracture seemed phase seperation. Under the impact load, the notched izod impact strength increased as rubber content, molecular weight, ambient temperature and lubricant content increased. In the SEM picture, the strength was high white the fracture surface was small.

• School Mathematics
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• v.14 no.2
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• pp.233-253
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• 2012

The purpose of the study investigate mathematics content knowledge(MCK) of prospective teachers in differential area. 70 prospective teachers were asked to perform six questions based on Cho's MCK (2010, 2011). The results show that depending on whether they experience any teacher education program, the level of prospective teachers' mathematics content knowledge may vary. In particular, prospective teachers struggled with an unfamiliar problem situations. We also found that prospective mathematics teachers have some difficulty in solving problem about the use of mean value theorem and derivative.

• Journal of Distribution Science
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• v.12 no.7
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• pp.63-75
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• 2014

Purpose - This study analyzes topics discussed in the International Journal of Consumer Studies through a content analysis, to reveal the impact of cross-cultural management in consumer research. Research Design, Data, and Methodology - The International Journal of Consumer Studies has the highest impact factor among international consumer journals, and was chosen for research. This study investigated 712 articles, covering a ten-year period. Results - A total of 82 articles were found to be related to cross-cultural management, out of 712 articles. This shows a need for improvement in the area of cross-cultural management, and implies that the discipline of cross-cultural management will continue to have a significant impact on consumer studies. Conclusions - While content analyses have been conducted in the area of consumer research in the past, a comparative content analysis in the International Journal of Consumer Studies is unprecedented. This study offers insights on the comparative analysis of general articles and articles related to cross-cultural management, which will be useful reference points for future global markets and fields in distribution and consumer research.

• Journal of The Korean Society of Agricultural Engineers
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• v.48 no.3
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• pp.3-8
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• 2006

The fractions of nitrogen were investigated in the soils of reclaimed and natural tidelands of southwest coastal area of Korea. The content of total-N varied to ranged form 619 to 5,534 mg/kg dry weight with a mean value of 1,857 mg/kg. The order of different fractions of nitrogen was as follows: Acid non-extractable-N > uncounted-N > acid extractable-N > ammonia-N > nitrate-N. The content of ammonia-N, acid extractable-N, and acid non-extractable-N showed highly negative correlations with pH. The content of acid extractable-N and ammonia-N showed highly positive correlation with clay content.

• Journal of the Korea Society of Computer and Information
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• v.22 no.12
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• pp.87-93
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• 2017

The purpose of this study is to design and develop of digital contents to improve computational thinking in the online education environment. First, we planned the design and development of contents with 19 experts of Software education. Digital content was designed from the point of view of improving the educational quality and the quality of contents for the improve of computing thinking. The content type is classified into the SW education area; computer science, programming, physical computing, convergent computing, computing thinking, and software education that improves the computing thinking. And we designed 45 learning programs for each SW education area. Designed learning contents were developed in 464 lessons to suit the online education environment. The content validity of the proposed content was verified by the expert group and the average CVI value was over .83. Through this, we could analyze that the developed contents will help learners to expand their computing thinking.

• Journal of Korean Academy of Nursing
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• v.27 no.1
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• pp.96-108
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• 1997

The purpose of this study was to determine the effect of endurance training prior to occurrence of muscle atrophy on the mass, myofibrillar protein content and fiber crossectional area of atrophied hindlimb muscles of rats. Adult female Wistar rats were trained prior to occurrence of muscle atrophy induced by hindlimb suspension. Training began on the 1st day for 10min /day at 15m /min on a 0% grade, training exercise increased daily in time and intensity so that by the 4th week rats were running 60min /day, at 34m /min on a i3.5% grade. Wet weight and relative weight of soleus, plantaris and gastrocnemius muscle decreased significantly after seven days of hindlimb suspension. Wet weight and relative weight of soleus tended to increase and that of plantaris and gastrocnemius tended to decrease in the exercise group as compared to the control group. Myofibrillar protein content of soleus and gastrocnemius tended to increase and that of plantaris tended to decrease in the endurance trained group as compared to the control group. Fiber crossectional area of Type I, II fiber in soleus and plantaris muscle tended to increase in the exercise group as compared to the control group. Wet weight and relative weight of soleus. plantaris and gastrocnemius decreased significantly, myofibrillar protein content of soleus, plantaris and gastrocnemius increased in hindlimb suspended rats following endurance training as compared to the control group. There was no change in fiber type percentage and crossectional area of type I and II fiber in soleus muscle and that of type I and IIfiber in plantaris muscle decreased in the hindlimb suspended rats following endurance training as compared to the control group. Wet weight and relative weight of soleus and plantaris tended to increase, that of gastrocnemius increased significantly, myofibrillar protein content of soleus and plantaris muscle increased significantly and that of gastrocnemius tended to increase in the hindlimb suspended rats following endurance training as compared to sedentary rats following endurance training. Crossectional area of type I fiber of soleus muscle tended to increase. that of type I fiber of plantaris muscle increased significantly and that of type II fiber tended to increase in hindlimb suspended rats following endurance training as compared to sedentary rats following endurance training. The results suggest that endurance training prior to occurrence of muscle atrophy can attenuate the decrease of mass, myofibrillar protein content and fiber crossectional area induced by hindlimb suspension.

• Journal of the Korean Society of Earth Science Education
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• v.9 no.3
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• pp.269-275
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• 2016

This study is conducted to search about changing earth science contents influenced by the scientific literacy from the 7th curriculum to the 2015 revised curriculum. Earth science area is divided into astronomy, geology, meteorology and oceanography contents. Among the elements of scientific literacy, the contents were analyzed focusing on STS elements. In the astronomical and meteorological content areas, there were aspects of scientific literacy in all periods from the 7th to the 2015 revised curriculum. Except for the 2007 revised curriculum in the geological area and the 7th curriculum in the oceanographic content area, the aspects of scientific literacy appeared at all times. It is emphasized the usefulness of science and technology in the astronomical content area and the use of science in everyday life in geological and meteorological content area. In the oceanographic content area, it is emphasized that content of science related social issue such as resource shortage and environmental pollution. This study can be extended to the fields of physics, chemistry and life science, we suggest to inquire the scientific literacy as a integrated science.