• Journal of Preventive Medicine and Public Health
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• v.21 no.2 s.24
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• pp.307-319
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• 1988

In order to determine the contents of lead, cadmium and zinc, the tissues of the crussian carp, Carassius carassius, collected from the middle streams of the Nakdong river were examined. During the dry season from 8 to 15, March, 1987, six loci were selected to sample the fish and river water; five of them were the midstreams of the Nakdong river i. e., the vicinities of the Andong dam, the Nakdong bridge, the Waegwan bridge, Gangjung and Gaepori, the other one was the Kumho river around the Paldal bridge(see Fig. 1). The microanalyses of lead and cadmium contents were undertaken by the atomic absorption spectrophotometer(Model IL-551) connected with CTF-IL 655, while that of Zinc by the flame method with IL551 only. The contents of lead and cadmium in water sampled from Gaepori distant from about 30km downward from the junction with the Kumho river were about 1.5 times higher than those from Gangjung distant about 0.5km upward from the junction, and the content of zinc from Gaepori was slightly higher than that from Gangjung. However, the contents of lead and cadmium in water sampled from Gaepori were three fifth of those from the vicinity of Paldal bridge far about 2km upperward from the junction. In the other words, the contents of lead and cadmium in the samples from the vicinity of the Paldal bridge were about 2.5 to 3 times higher than those from the Gangjung and 5 times higher than those from the Andong dam. The contents of the heavy metals in the tissues of Carassius carassius were relatively consistent to those of the aquatic environments where the fish were collected, with higher contents in the tissues of the crussian carp collected from the vicinity of Gaepori and the Paldal bridge which were so much polluted than in those from other loci in upper stream from the junction. And the contents of lead and cadmium in tissues were positively correlated with the age of the fish, however, that of zinc was not. The contents of lead in bone of crussian carp from the vicinity of the Paldal bridge in the group of 0-1 year old fish were similar to those of 4-5 years old fish from Gaepori, and higher than those of 3-4 years old fish collected from the upper stream of the junction. It is likely that fishing from Gaepori and the paldal bridge is not recommended, and all the industrial producers have to pay intensive attention to the water pollution due to the sewage disposal.

• Korean Journal of Weed Science
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• v.14 no.2
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• pp.120-127
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• 1994

To establish an efficient herbicide screening method for purple nutsedge(Cyperus rotundus) control, its sprouting characteristics, tuber production and responses on several herbicides were investigated under greenhouse condition. The tubers stored at $4^{\circ}C$ after sterilization with the diluted prochloraz(Spotac) solution showed higher sprouting than the non-sterilized did. The harvested tubers were not dormant, and the sterilized tubers which stored at low temperature had a sprouting capability of about 80% after 6 months. If the fresh weight of purple nutsedge tubers was decreased to below 48%, they could not sprout. However, the tubers soaked in water and then stored at low temperature could sprout by 88% even 6 months later. Sprouting and initial growth of tuber were much better at $35^{\circ}C$-day/$25^{\circ}C$-night than at 30/$20^{\circ}C$ or 25/$15^{\circ}C$. The half-sected tubers, which were prepared by setting the intact tuber of above 1.2g latitudinally, were shown similar initial growth to the intact but those sected crucifically were not. These results suggest that the half-sected tuber itself can be used as a material on herbicide screening. About 1000 tubers could be harvested when 10 tubers planted in a pot($56{\times}35{\times}16cm$) filled with the artificial soil were cultivated in greenhouse of $35^{\circ}C$-day/$25^{\circ}C$-night for 3 months(April-July, 1993). Chlorimuron, Bentazon and Norflurazon were selected as the standards for the screening because of providing relatively effective control on purple nutsedge in both soil-surface and foliar spray treatment.

• Korean Journal of Microbiology
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• v.50 no.4
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• pp.345-350
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• 2014

The aim of this study was to investigate the effect of high temperature on the viability of probiotic organisms (Bacillus subtilis, Lactobacillus plantarum, and Saccharomyces cerevisiae) mixed with animal feed under controlled conditions by simulating a farm feed bin in the summer. Following inoculation of probiotics into the feed, the pH and probiotic viability were monitored during an 8-day incubation at room temperature. Sterile and non-sterile feeds displayed different patterns of pH changes, with increased pH in non-sterile feed at 2 days, but a pattern of decreasing pH at 4 days. The viabilities of S. cerevisiae and B. subtilis after mono/co-inoculation were maintained without substantial changes during the incubation, whereas L. plantarum viability tended to decline. In both non-sterile and sterile feeds, the probiotics were maintained or grew without any antagonistic effects. Probiotic viability was also tested upon a shift to high temperature ($60^{\circ}C$). There was no distinct change in pH between sterile and non-sterile feeds after the temperature shift. L. plantarum and S. cerevisiae could not survive at the high temperature, whereas B. subtilis displayed normal growth, and it inhibited the growth of contaminant microbes. Fungal growth was not observed in non-sterile feed 2 days after supplementation with B. subtilis. Therefore, heat resistant B. subtilis could be safely used in feed bins to inhibit microbial contamination, even at high temperatures. The prevention of elevated temperature in feed bins is necessary for the utilization of L. plantarum and S. cerevisiae during the summer season.

• Journal of Korean Home Economics Education Association
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• v.21 no.1
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• pp.89-106
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• 2009

The purpose of this study was to investigate the perspectives on curriculum of secondary school home economics(HE) teachers, the HE teacher efficacy level, and the correlation between their perspectives on HE curriculum and the HE teacher efficacy. A questionnaire survey was carried out to the 500 HE teachers from middle and high schools across the nation, 215 questionnaires were used in the final analysis. The findings of this study were as follows: First, most of HE teachers had the biggest interest in interpretative perspective and some teachers had a interest in critical perspective. On the other hand, a few teachers only had a interest in technical curriculum perspective. Second, HE teachers who worked in the big cities tended to be more interested in interpretative perspective than those who worked in small cities. HE teachers from 25 to 40 years olds tended to be more interested in critical perspective than those who were more than 50 years old. Also, HE teachers with less than 15 years of experience tended to be more interested in critical perspective than those who had worked for more than 15 years. Third, the average of the HE teacher efficacy level was 3.69. The efficacy level of studying support was the highest. Then came class support, environment support, instruction strategy, and demands alternation in order. Fourth, there was moderate correlation between the interpretative perspective on curriculum of middle and high school HE teachers and teacher efficacy level in comparison with other curriculum perspectives.

• Korean Journal of Health Education and Promotion
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• v.18 no.1
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• pp.109-125
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• 2001

The purpose of this study was to provide the basic data for establishing school education environment protection measures, on the basis of comparing and analyzing the realities and students' recognition degree of the environment and hygiene around the middle and high schools located in the rural areas. These study data were investigated by the self-administered questionnaires, taking as subject the 805 students in the middle and high schools located rural areas. And the results were as follows: First, as the result of having investigated the distribution degree of harmful environment within the purification zone around schools, it was found out that students responded: within the purification zone around the middle school, there were cartoon rooms (46.2％), electronic game rooms (45.9％), and singing rooms (45.0％). within the purification zone around the high school, there were electronic game rooms (46.3％), singing rooms (42.3％), billiard halls (41.4％), PC rooms (40.1 ％), and Soju-room (35.2％). Secondly, as having analyzed student's recognition degree of the harmful environment around the school, it was found out that middle school students responded that sexual utensils-treating shops (3.74 points) were most harmful, and next corrupted bathhouses (3.52 points), and Soju-room (3.47 points), and high school students also responded relating to harmfulness in a similar sequence. Thirdly, in case of students' recognition degree of the harmful environment around the school according to general characteristics, 1) girl students had a higher ratio of recognition that the environment around the school was harmful than boy students (p〈0.001). 2) groups of students whose living standard was high had a higher ratio of recognition that the environment around the school was harmful than groups of students whose living standard was low (p〈0.05). 3) groups of students whose school was located near the park or the residential street had a higher degree of recognition that the environment around the school was harmful than groups of students whose school was located near the factory or the shopping area (p〈0.01). 4) groups of students whose school was located near the park or the residential street had a higher degree of recognition that the environment around the school was harmful than groups of students whose school was located near the amusement area or the shopping area (p〈0.05). Fourthly, 1) relating to the harmful shops where they experienced most highly the behavior of drinking and smoking, middle school students responded that they did so in the electronic game room (22.5％) and high school students did so in the singing room (31.4％), and high school students had a very high experience ratio of drinking and smoking, compared with middle school students (p〈0.001). 2) relating to the harmful shops where they could get in contact with lewd articles, both of middle school students (5.3％) and high school students (8.3％) responded that they could do so in the video room. 3) relating to the harmful shops where they experienced unsound opposite sex acquaintance, both of middle school students (5.8％) and high school students (16.6％) responded that they did so most highly in hotels, and high school students had a remarkably high experience ratio of unsound opposite sex acquaintance, compared with middle school students (p〈0.05). 4) relating to the harmful shops where they experienced violence, middle school students responded that they did so in the electronic game room (14.0％) and then in the singing room (3.7％), and high school students responded that they did so in the electronic game room (9.3％), the nightclub (4.6％), Soju-room (4.1 ％), and high school students had a remarkably high experience ratio of violence, compared with middle school students (p〈0.05). 5) relating to the harmful places where they experienced drugs both of middle school students (0.8％) and high school students (2.4％) responded that they did so in the hotels. Fifthly, when going to the harmful shops, students had the experience of being guided and regulated roughly 1 time - 2 times, and middle school students (16.4％) and high school students (16.7％) had almost similar experience ratios of being guided and regulated. Conclusively, there was a limit in controlling the environment and purification zone only by legal regulations and institutional controls, the self-control purification effort for the school and the surrounding environment was required greatly, in order to protect students from harmful environment. In addition, the constant study to establish the educational environment purification measures must be carried out.

• KEPCO Journal on Electric Power and Energy
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• v.6 no.3
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• pp.305-313
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• 2020

The use of cable tunnels for electric power transmission as well as their construction in difficult conditions such as in subsea terrains and large overburden areas has increased. So, in order to efficiently operate the small diameter shield TBM (Tunnel Boring Machine), the estimation of advance rate and development of a design model is necessary. However, due to limited scope of survey and face mapping, it is very difficult to match the rock mass characteristics and TBM operational data in order to achieve their mutual relationships and to develop an advance rate model. Also, the working mechanism of previously utilized linear cutting machine is slightly different than the real excavation mechanism owing to the penetration of a number of disc cutters taking place at the same time in the rock mass in conjunction with rotation of the cutterhead. So, in order to suggest the advance rate and machine design models for small diameter TBMs, an EPB (Earth Pressure Balance) shield TBM having 3.54 m diameter cutterhead was manufactured and 19 cases of full-scale tunneling tests were performed each in 87.5 ㎥ volume of artificial rock mass. The relationships between advance rate and machine data were effectively analyzed by performing the tests in homogeneous rock mass with 70 MPa uniaxial compressive strength according to the TBM operational parameters such as thrust force and RPM of cutterhead. The utilization of the recorded penetration depth and torque values in the development of models is more accurate and realistic since they were derived through real excavation mechanism. The relationships between normal force on single disc cutter and penetration depth as well as between normal force and rolling force were suggested in this study. The prediction of advance rate and design of TBM can be performed in rock mass having 70 MPa strength using these relationships. An effort was made to improve the application of the developed model by applying the FPI (Field Penetration Index) concept which can overcome the limitation of 100% RQD (Rock Quality Designation) in artificial rock mass.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.1
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• pp.43-56
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• 2012

The purpose of this study was to propose management strategies through aesthetic landscape assessments for landscape units in the Han River riparian(HRR) area. First, this research reclassified the HRR into "natural," "artificial," "agricultural," and mixed landscape types and selected 37 representative case areas(about $1km{\times}1km$). This study found 71 landscape units in consideration of topography and land surface classification. Landscape assessment consisted of landscape quality and landscape integration assessment. The criteria for assessing landscape quality were "naturalness," "interest," "uniqueness," and "landscape function." "Landscape quality" was ranked into five grades using a matrix. The landscape integration assessment consisted of an inner integration assessment in each landscape unit and outer integration assessment among landscape units. As a result of the field study, case sites were found to have 4,288 landscape units and an area of $42.8km^2$. The forest area was found to have the most space with $11,580,905m^2$(27.1%), while the wet lands had just $52,348m^2$(0.1%). In the landscape quality assessment, about 30.5% of the total area consisted of landscape units that scored highest in "naturalness". In the landscape integration assessment, about 39.3% of the total area consisted of landscape units which scored highest in "integration", denoting visual interrelation and harmony. The existence of disparities in landscape quality in accordance with the form of the landscaping was determined using a Oneway ANOVA, with "naturalistic" landscaping scoring the highest and "artificial" landscaping scoring lowest. This study may contribute to making the HRR area a more ecologically sound and visually attractive landscape space. It is recommended that the aesthetical and ecological value of the landscape unit should be assessed simultaneously in the future.

• The Journal of Engineering Geology
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• v.18 no.4
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• pp.471-482
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• 2008

This study was carried out to investigate the contamination characteristics of surface water, soil water and groundwater around and in antimony waste landfill site in Wonsung-ri, Yeonki-kun, Chungnam. The waste disposed in the study was excavated and transported to the other site in several years ago. For this study, we collected 35 water samples including groundwater, soil water and surface in the study site and also collected 2 groundwater samples from a comparison site. The data of chemical analysis of soil water samples show the antimony concentration of $48.75{\sim}74.81\;ppb$, which is much higher than groundwater in a comparison site and is highly excess than regulation level for a drinking water of some advanced countries. A relatively high antimony concentration was detected in three stream water samples nearby landfill site and two groundwater samples. Fe and Mn contents in soil water and stream water were measured as maxium 6.5 mg/L and 7.3 mg/L, respectively. Although other heavy metals of water samples in the study site are higher concentration than water sample of comparison site, their absolute levels are lower than regulation level for a drinking water. The chemical data of water samples are plotted widely from Ca - $HCO_3$ type to Ca - ($Cl +SO_4+NO_3$) type. Some groundwater show high contents of potassium and nitrate, which would come from fertilizer and sewage. Conclusively, some heavy metals including antimony have been still remained under the soil surface of the landfill site in the past. These metals have leaked out into nearby stream and groundwater system, and threaten the ecology, crops and the health of residents in this site. Therefore, the government have to prepare the strategy to prevent the diffusion of heavy metals into aquatic environment and have to process the reclamation work for contaminated site. It is also necessary to make a regulation level of the antimony concentration for a drinking water and soil environment in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.55 no.2
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• pp.144-150
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• 2010

The agricultural techniques of environmental friendly using the green manure crops have been required recently more to have the safety agricultural products and to reduce the use of fertilizers and agricultural chemicals. The utilization of green manure crops related closely to cropping system would be very important. The purposes of this study are both to investigate the effects of green manure crops of hairy vetch, legume, and rye, gramineae, and to compare the effects between them in rice cultivation. The hairy vetch and rye were treated as green manure crops into paddy soil at 10 days before the rice transplanting. The plant height was increased gradually from the maximum tillering to the heading growth stage, showing that it was the highest with treatment of conventional cultivation in 2007 and the highest with hairy vetch in 2008. The number of tillers was higher with treatment of hairy vetch and hairy vetch+rye than those with the conventional cultivation. Dry weight was also higher with hairy vetch than that with the conventional, while it was lower clearly in rye than those in hairy vetch and conventional. According to the high tilller number and spikelet number per panicle out of the yield components relatively, the yield of rough rice was increased to about 6% and 8% in 2007 and 2008, respectively, comparing with the yield in the conventional cultivation. Based on these results, the hairy vetch would be a good green manure crop in rice cultivation.

• Archives of design research
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• no.16
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• pp.41-51
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• 1996

A matter of primary concern about all design is concentrated on how to create more valuable things to allow people to live an affluent life. However, it is very difficult to achieve the goal because every design work is changed in accordance with given situatio ns. In this sense, it is significant to study on biodesign because it can be both a basic principle and a fudamantal index to show the way of new design direction. Accordingly, the main purpose of the thesis is to catch every meaning of bio-design and to close analyze its factors in order to generate more fresh ideas and put them into practice. The thesis is composed of five Chapters: Introduction, Background of bio-design, Principle of bio-design, Practice of bio-design, and Conclusion. In Introduction, the purpose and background of the study are presented. I n Chapter 2, source of design orgin, vernacular design, and design for life are researched. In Chapter 3, organic order. the survial of the fittest, and subjective & objective are considered. In Chapter 4, hi-tech & hi-touch, criteria of problem -solving, and harmony with nature are searched. In Conclusion, some suggestive words on the study are mentioned.