• Analytical Science and Technology
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• v.13 no.4
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• pp.403-411
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• 2000

This study described a method of thermoluminescence dating of pottery shards using subtraction method. TL measurement was achieved using two different types of samples prepared by quartz inclusion method and fine-grain technique. Fine grains (size range: $5-10{\mu}m$) were separated by suspending grounded pottery samples into acetone solution and sedimentation quantitatively. In quartz inclusion method quartz grains in the size range of 90 to $125{\mu}m$ diameter were obtained by extracting the quartz crystals embed in the pottery shards and etching them with 1.0 M HF solutions. The archaeological dose of both the quartz and fine grains was determined from the dose calibration curves obtained from sequential irradiation of $^{137}Cs$ gamma and $^{241}Am$ alpha source to the samples and TL measurement of natural samples, in which the alpha dose of 4.60 Gy for the Packjae pottery was obtained using subtraction method. Annual alpha dose rates ($3.05{\pm}0.11$ mGy/yr.) were determined by the analysis of U, Th contents in the pottery shards and evaluation of the values with Bell's equation. Dividing the alpha dose accumulated in the pottery shards by the annual alpha dose rate, we found age of approximately $1508{\pm}80$ years B.P. (AD. ca. 492 yr.) for the Packjae pottery. It matches well with the archeological age estimate (middle of 5th century) within 10 percent uncertainty and thereby conforms the age of the pottery sample.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.4
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• pp.143-150
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• 2009

Deicing salt is used to melt snow and ice on the road for traffic safety during the winter season, which accumulates in the roadside vegetation and induces visible injuries. The damage may accelerate particularly when it coincides with early spring leaf out. In order to better understand the response mechanisms, C. kousa (3-year-old) was irrigated twice prior to leaf bud in a rhizosphere with solutions of 0.5, 1.0, and 3.0% calcium chloride ($CaCl_2$) concentration, that were made by using an industrial $CaCl_2$ reagent practical deicing material in Seoul. Physiological traits of the mature leaves were progressively reduced by $CaCl_2$ treatment, resulting in reductions of total chlorophyll contents, chlorophyll a:b, photosynthetic rate, quantum yield, stomatal conductance, $F_V/F_M$, and NPQ. On the contrary, light compensation point and dark respiration were increased at high $CaCl_2$ concentration. A decrease in intercellular $CO_2$ concentration by stomatal closure first resulted in a reduced photosynthetic rate and then was accompanied by low substance metabolic rates and photochemical damage. Based on the reduction of physiological activities at all treatments ($CaCl_2$ 0.5%, 1.0%, and 3.0%), C. kousa was determined as one of the sensitive species to $CaCl_2$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.2
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• pp.1176-1187
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• 2014

In Contemporary residential area, especially apartment commplex, crime affect the quality of life and sustainability of cities. So our interest is an all-time high in the role that planning processes and the design of the physical environment can play in reducing the opportunity for crime. The purpose of this study try to find the possibility of application of CPTED in Urban Apartment Complex. Recently, as increase of residencial density, diverse and new types of crime are increasing in urban apartment complex. It is the current of times which demand our serious consideration. This research focused on crime reduction through the physical environmental control methods. And the concepts and contents of CPTED are studied and the case studies of developed countries are surveyed. For groping in the practical application, researched into the case study of apartment blocks in medium sized city, Cheongju. Also Local crime prevention initiatives require partnership working, both between professionals and with local communities. The result of this study has implicated, increasing importance on daily safety issue in urban life and examining the possibility of applying crime prevention and reduction program and systems.

• Korean Journal of Food Science and Technology
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• v.42 no.2
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• pp.240-245
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• 2010

Brown rice of Korea and China was irradiated at doses ranging from 0 to 15 kGy to verify the identification properties of viscosity measurement by determining the relationship between starch content and specific parameters. The starch contents of brown rice were 71.52 and 64.58% for rice of Korea and China, respectively. Additionally, a higher starch content was associated with a higher viscosity. The viscosity and the corresponding specific parameters decreased significantly as the irradiation dose increased, and these changes were influenced by the spindle speed (50, 150, 300 rpm), with a higher effect being observed at lower speeds. The determination coefficients ($R^2$) describing the relationship between irradiation dose and viscosity values ranged from 0.9423 to 0.9567 in Korean samples and from 0.9119 to 0.9387 in Chinese samples. The viscosity and the corresponding specific parameters enabled identification of the non-irradiated and irradiated brown rice from 30 unknown samples with an accuracy of 90%. Based on these findings, the viscosity and specific parameters can be applied as an additional tool for screening of irradiated brown rice.

• The Korean Journal of Food And Nutrition
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• v.27 no.1
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• pp.31-42
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• 2014

This study was conducted to evaluate the effect of gamma irradiation (0.4, 0.6, 0.8, 1 and 1.5 kGy) on the microbiological, physicochemical and sensory qualities of imported orange during storage at $3^{\circ}C$ for 60 days. Total aerobic bacteria and yeast/mold counts in non-irradiated oranges were 3.59 and 3.75 log CFU/g, and those counts in irradiated oranges at 1.5 kGy were decreased by 1.75 and 2.26 log CFU/g, respectively. Moreover, those counts were decreased significantly according to a dose-dependent manner after gamma irradiation. The pH revealed no significant difference between the control and irradiated samples; however, titratable acidity was decreased significantly according to a dose-dependent manner and storage time. The vitamin C contents were decreased significantly according to a dose-dependent manner and storage time after gamma irradiation. Further, sensory evaluation testing revealed no significant difference between the control and irradiated samples, except 1.5 kGy. Samples irradiated at 1.5 kGy had the lowest values in color, sweetness, sourness, flavor, texture and overall acceptance. The results suggest that gamma irradiation was effective for ensuring microbiological safety; however, irradiated oranges at 1 and 1.5 kGy did not have good physicochemical and sensory qualities. Therefore, we can use the sample irradiated at 0.4~0.6 kGy as optimum-dose to be minimize on quality changes.

• Resources Recycling
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• v.21 no.1
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• pp.17-29
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• 2012

potential assessment of converting closed non sanitary landfills into sustainable landfill through the reclamation works(= landfill mining project) of illegal landfill discovered in land development site using Sustainable Landfill Reclamation system(SLR-system) was investigated. The SLR system had treatment capacity of 91.4 $m^3/hr$ (130.61 ton/hr) in condition of 28.0% of water content. Recovery ratio and purity of sorted soil were 98.9% and 99.66%, respectively. Sorted combustibles were 91.8% and 92.0%, respectively. Especially, high heating value (HHV) and low heating value(LHV) of combustibles were 4,282kcal/kg and 3,636 kcal/kg, respectively, in considering the energy content and recovery ratio of combustibles. Therefore, combustibles separated from landfill site have higher value than Fluff RDF standard value(3,500kcal/kg) of MOE. RDF can be produced with combustibles by 84.43%. Averaged size and organic foreign matter content of the sorted soil were less than 035mm and 0.31 %(VN), respectively. In addition, concentration of all contents of hazardous matters containing soils met safety standards. Therefore, it is possible to be recycled as refilling and cover materials to rebuild Sustainable landfills by 98.42%.

• Elastomers and Composites
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• v.38 no.3
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• pp.227-234
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• 2003

Silicone composites for high voltage insulator (HVI SC) were prepared by adding aluminum trihydrate(ATH) treated by surface treatment agent to base silicone compound at the ratio oi 100:20, 100:40, 100:60, 100:80, and 100:100, respectively And also, ATH was treated by various surface treatment agents, such as stearic arid, acryl silane, and vinyl silane under compounding process. Mechanical properties and electrical properties were investigated for the various contents of ATH and surface-treatment agents. Mechanical properties such as tensile strength, elongation, and tear strength decreased as the load of ATH increased. Volume resistivity, AC break down strength, and tracking resistance for HVI SC containing ATH treated by vinyl silane were better than those for HVI SC containing ATH treated by other surface treatment agents, such as stearic acid and acryl silane. Polymer-filler interaction of silicone composites according to surface treatment agents was studied by measuring bound rubber contend(BR). From the experimental results, BR of silicone composite containing ATH treated with vinyl silane was higher than that of the others. The degree of rule for silicone composite was investigated using Rheometer. Maximum torque of silicone composites contaning ATH treated with vinyl silane was higher than that of silicone composite contaning ATH treated with other surface agents.

• Food Science and Preservation
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• v.12 no.4
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• pp.355-360
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• 2005

This study was carried out to research the use of tar colors in children's favorite foods such as candies, soft drinks, chewing gums, cereals, and ice bars in order to acquire basic data on food safety. The tar colors were simultaneously analyzed by high performance liquid chromatography (HPLC). The contents of tar colors in candies, soft drinks, gums, cereals, and ice bars were maximum 74.10 mg/100 g, 5.96 mg/100 g, 35.70 mg/100 g, 20.10 mg/100 g, and 4.93 mg/100 g, respectively. In addition, every tar colors except for Indigo carmine (B2) and Fast Green FCF (G3) among permitted tar colors were used in foods and more than two kinds of tar colors were used in most cases. From the results, only types of tar colors for foods were regulated, but the amount was not regulated.

• Food Science and Preservation
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• v.18 no.3
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• pp.302-309
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• 2011

This study was performed to analyze the physicochemical and sensory properties of Acanthopanacis cortex and Aralia elata according to their blanching conditions and thawing methods. In terms of their Hunter colors, the A. cortex and A. elata that were blanched without adding salt to them for 7 min and 4 min, respectively, had the highest L values. The chlorophyll content (148.7 mg%) of A. cortex that was blanched with 1% salt for 4 min was higher than those of the other samples, and the chlorophyll content of A. elata was 32.4 mg% when it was blanched for 4 min without salt addition. The sensory test results showed the highest overall preference for the sample that was blanched without salt for 4 min among all the samples. The Hunter color of A. cortex did not significantly differ with different thawing methods, but the value of A. elata that was thawed in a microwave oven was higher than those of the other samples. The chlorophyll contents of A. cortex and A. elata that were thawed in a microwave oven were the highest among all the samples. As for the overall preference for the samples according to the thawing method, A. cortex and A. elata scored highest in the case of thawing at $25^{\circ}C$ and in a microwave oven, respectively.

• Journal of the Korean Society of School Health
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• v.18 no.1
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• pp.1-14
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• 2005

Purpose: The purpose of this study was to identify the needs of health education in students, their parents and teachers in the elementary, middle and high schools and the current situation of health education class. Method: The subjects of this study were a total of 9450 persons including students, their parents and teachers from 279 schools throughout the country. They were selected through convenient sampling. Data were analyzed through $\chi^2$-test and ANOVA. Result: Students, their parents and teachers replied that 18 dimensions of health education class (DHEC) are necessary. The four DHEC - healthier life style, sex education, mental health and safety education - showed high educational needs in students, their parents, and teachers. High school students had higher educational need of 'symptom management for daily living' than elementary and middle school students. Students, their parents and teachers in elementary school had higher educational needs of 17 DHEC than those in middle and high school. The percentages of schools with health education class taught by health teachers were 99.2%, 75.5% and 66.0% respectively in elementary, middle and high schools. Health education was given mainly using physical education classes at elementary schools, and creative class hours at middle and high schools. In general, health education took 1-3 hours per week at elementary schools, and less than an hour at middle and high schools. Conclusion: Therefore, based on the results, systematic health education class should begin from elementary school to meet the need of health education in students, their parents and teachers, and further study should be made on the number of hours required and the amount of contents of 18 DHEC.