• Economic and Environmental Geology
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• v.38 no.4 s.173
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• pp.463-479
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• 2005

The Sr and Pb isotopic ratios and chemical composition were measured for atmospheric bulk deposition samples collected in the Jeonju, Gunsan and Namweon areas over a period of one year. Acidity of deposition ranged pH $4\~7$ with little higher in dry season, and around pH 5.0 in rainy season. The EC and TDS of rainy season was low showing dilution effect, and increased during dry season. Sulfate $(SO_4)\;and\;NO_3$ are atmospheric aerosols largely of anthropogenic origin in winter. Sodium was concentrated in winter deposition, Ca was concentrated in spring to summer deposition. Namweon has lower EC and TDS than those of other, and Jeonju has higher. Namweon was concentrated in $HCO_3$ and Cunsan was concentrated in Cl. Aluminium, Cu, and Zn show good correlation index with TDS, indicating of their origin atmospheric. $^{87}Sr/^{86}Sr$ ratios of bulk deposition ranged from 0.7109 to 0.7128. The isotopic variations are correlated with mixing of isotopic compositions of local soils, road deposit and biogenic aerosol. In order to constrain further the origin of aerosols in rainwater, it will be necessary to collect additional Sr isotopic data for aerosols. Lead isotope ratios for all areas were similar and belonged to Pb isotope ratios of Seoul's aerosols, but little different with Beijing's aerosols. It showing that Pb in the Korea mainly derived from the gasoline combustion, not exclusively from the Beijing.

• Economic and Environmental Geology
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• v.50 no.3
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• pp.215-224
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• 2017

Arsenic (As) is known to be the most toxic element and frequently detected in groundwater environment. Inorganic As exists as arsenite [As(III)] and arsenate [As(V)] in reduced and oxidized environments, respectively. It has been reported that the toxicity of arsenite is much higher than that of arsenate and furthermore arsenite shows relatively higher mobility in aqueous environments. For this reason, there have been numerous researches on the process for oxidation of arsenite to arsenate to reduce the toxicity of arsenic. In particular, photooxidation has been considered to be simple, economical, and efficient to attain such goal. This study was conducted to evaluate the applicability of naturally-occurring goethite as a photocatalyst to substitute for $TiO_2$ which has been mostly used in the photooxidation processes so far. In addition, the effects of several factors on the overall performance of arsenite photocatalytic oxidation process were evaluated. The results show that the efficiency of the process was affected by total concentration of dissolved cations rather than by the kind of those cations and also the relatively higher pH conditions seemed to be more favorable to the process. In the case of coexistence of arsenite and arsenate, the removal tendency by adsorption onto goethite appeared to be different between arsenite and arsenate due to their different affinities with goethite, but any effect on the photocatalytic oxidation of arsenite was not observed. In terms of effect of humic acid on the process, it is likely that the higher concentration of humic acid reduced the overall performance of the arsenite photocatalytic oxidation as a result of competing interaction of activated oxygen species, such as hydroxyl and superoxide radicals, with arsenite and humic acid. In addition, it is revealed that the injection of oxygen gas improved the process because oxygen contributes to arsenite oxidation as an electron acceptor. Based on the results of the study, consequently, the photocatalytic oxidation of aqueous arsenite using goethite seems to be greatly feasible with the optimization of process.

• Korean Journal of Environmental Agriculture
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• v.21 no.1
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• pp.50-56
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• 2002

This experiment was carried out to obtain some information about overwintering, physiological and ecological characteristics of apple snails. Another purpose of this experiment was to characterize an appetite for rice plants by apple snails and to elucidate their choice of fresh green ones (vegetables, some other crops, weeds in rice fields). The freshwater snails were found with higher population at sites abundant organic compounds such as plant debris and at regions with high temperature. They also prefer calcium-rich water. This is a naturally occurring process. Apple snails were exceptionally veil-adapted to the south regions of Korea, especially Janghang, Jangseong and Haenam, even if the temperature of winter season is cold below 0$^{\circ}C$. Apple snails were not very selective in their food choice and eat almost everything available in their environment. A snail have something called a radula in its mouth for grinding up its food. A apple snail also chews on fruits and young succulent plant barks. In case of reproduction. apple snails deposit about 157$\sim$784 (average of 321 eggs) milky white to pale orange colored eggs above the waterline. In approximately every 22.4 seconds a new egg appears. The total time needed to deposit a egg mass varies from 58 minutes$\sim$4 hours 13 minutes. Apple snails reproduct actively from May to June and from September to October. An appetite of apple snails for rice plants was the different depending on their size and glowing stage for rice plants. Apple snails had a great appetite of rice plants as well as dropwort, tomato, cabbage, radish, aquatic plants etc. They preferred to eat young rice plants and drastically quit eating rice plants of over 40 cm in height. Thus considering the food preference of apple snail for various plants including rice, they were thought to be a potentially strong predator in fields, especially, at regions with warmer winter.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.2
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• pp.40-55
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• 2015

This study aims to evaluate the efficiency of the forest experience center for children led by the local community as experiential management for forest kindergarten education. For this, an importance and performance analysis was conducted on the forest experience center for children in Geumcheon-gu, which, of the 12 forest experience center for kids in Seoul, is the only one led by the local community. The questionnaire sheet for the analysis consisted of a total of 36 questions, 20 about place facility areas and 16 about management program areas(including 6 questions about the management led by the local community). The questionnaire survey was done during the period between January 12th and January 19th, 2015. The participants in the survey consisted of 15 forest education specialists and 50 teachers from 19 kindergartens who participated in the forest experience program. The number of questionnaire sheets collected and used for analysis was 13 copies and 43 copies, respectively. The mean values of importance and performance on the place facility areas were 4.07 and 3.78 for forest education specialists, and 4.16 and 3.84 for kindergarten teachers, respectively. The mean values of importance and performance regarding the management program area were 4.38 and 4.16 for forest education specialists, and 4.40 and 4.00 for kindergarten teachers, respectively. Both groups evaluated the place facility areas lower than the management program areas. They also evaluated performance lower than importance. In place facility area, 'accessibility', 'safety' and 'connectivity to forest trail', 'loose parts' and 'safety facilities' were required to 'keep up the good work', because they showed higher importance and performance in place facility areas. Even though most items of management as led by the local community including 'forest experience activity support' were evaluated as 'important', some, including 'effort for local revitalization', were evaluated as low in performance. However, as they were evaluated as higher in importance, if they pursue 'concentrate here', it is expected that they will be evaluated as higher in performance. In addition, considering that program areas including 'forest education specialist's role' are labeled under the management led by the local community, it reflected a positive evaluation. As a result, management led by the local community is efficient as a management system for the forest experience center for children in an experiential forest kindergarten education. Going forward, if this management system is durable in 'keep up the good work' and 'concentrate here', the forest experience center for children led by the local community will be an alternative for an effective experiential forest kindergarten education.

• Korean Security Journal
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• no.27
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• pp.129-159
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• 2011

Physical security has always been an extremely important facet within the security arena. A comprehensive security plan consists of three components of physical security, personal security and information security. These elements are interrelated and may exist in varying degrees defending on the type of enterprise or facility being protected. The physical security component of a comprehensive security program is usually composed of policies and procedures, personal, barriers, equipment and records. Human beings kept restless struggle to preserve their and tribal lives. However, humans in prehistoric ages did not learn how to build strong house and how to fortify their residence, so they relied on their protection to the nature and use caves as protection and refuge in cold days. Through the history of man, human has been establishing various protection methods to protect himself and his tribe's life and assets. Physical security methods are set in the base of these security methods. Those caves that primitive men resided was rounded with rock wall except entrance, so safety was guaranteed especially by protection for tribes in all directions. The Great Wall of China that is considered as the longest building in the history was built over one hundred years from about B.C. 400 to prevent the invasion of northern tribes, but this wall enhanced its protection function to small invasions only, and Mongolian army captured the most part of China across this wall by about 1200 A.D. European lords in the Middle Ages built a moat by digging around of castle or reinforced around of the castle by making bascule bridge, and provided these protections to the resident and received agricultural products cultivated. Edwin Holmes of USA in 20 centuries started to provide innovative electric alarm service to the development of the security industry in USA. This is the first of today's electrical security system, and with developments, the security system that combined various electrical security system to the relevant facilities takes charging most parts of today's security market. Like above, humankind established various protection methods to keep life in the beginning and its development continues. Today, modern people installed CCTV to the most facilities all over the country to cope with various social pathological phenomenon and to protect life and assets, so daily life of people are protected and observed. Most of these physical security systems are installed to guarantee our safety but we pay all expenses for these also. Therefore, establishing effective physical security system is very important and urgent problem. On this study, it is suggested methods of establishing effective physical security system by using system integration on the principle of security design about effective security system's effective establishing method of physical security system that is increasing rapidly by needs of modern society.

• Korean Journal of Heritage: History & Science
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• v.53 no.2
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• pp.110-139
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• 2020

Reclamation is the act of creating new lands by constructing dikes in offshore tidal flats to utilize them for various purposes, including the establishment of farmland to secure food for an increasing population. Based on the fact that reclamation has resulted in drastic changes in the environmental, economic, social, and cultural aspects of land expansion and development, population movement, and the formation of cities since ancient times, I reviewed the value of reclamation sites and addressed the issue of how to preserve and utilize them. "Reclamation culture" refers collectively to the recognition and concept system, behavior styles, and cultural products created by changes in the environment, and the tangible, intangible, and natural heritage generated directly and indirectly by reclamation is defined as "reclamation cultural heritage". It shows that the historical background of reclamation accords with prevailing trends, and that the reclamation sites possess cultural heritage value due to their historical, academic, and scarce characteristics. Numerous reclamation cultural heritage sites at the Gwangwhal and Gyehwa dikes are on the verge of being destroyed, with their original function having ended after the construction of Saemangeum Sea Wall. I propose measures to preserve these under the principle that utilization is based on the basic premise of conservation. First of all, modern and contemporary reclamation sites must necessarily be designated and managed as registered cultural properties, local cultural heritage, future heritage, and agricultural heritage. In particular, as it has been confirmed that reclamation sites created after the Goryeo and Joseon dynasties and the 1950s have not been designated as cultural heritage sites. It is necessary to review the characteristics and values of such reclamation sites through a full survey of national reclamation data. Effective and sustainable utilization of reclamation cultural heritage, which has not been acknowledged in the past due to its close relationship with our lives, is necessary to search for hidden stories found within that heritage, to organize governance for the efficient use of reclamation resources, and to build a museum to collect and display the history and culture of the reclaimed areas. Finally, through links with countries with experience in reclamation, we will be able to cope jointly with international issues such as those pertaining to society, culture, and environment, and would be able to implement various projects to further the advancement of human beings.

• Korean Journal of Food Science and Technology
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• v.49 no.4
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• pp.430-437
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• 2017

The protective effect of Pteridium aquilinum on high glucose-induced cytotoxicity was examined in vitro to investigate the relationship between diabetic condition and neuronal dysfunction. The ethyl acetate fraction of P. aquilinum (EFPA), with total phenolic content of 265.08 mg gallic acid equivalent/g, showed higher 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)/2,2-diphenyl-1-picrylhydrazyl radical scavenging activities and lipid peroxidation inhibitory effect than any other fraction. In addition, EFPA showed a significant reduction in the inhibitory effect on ${\alpha}$-glucosidase activity ($IC_{50}$ value=$205.26{\mu}g/mL$) compared to the acarbose positive control. The anti-oxidative effect in PC12 cells, protective effects on high glucose-induced oxidative stress in neuronal cells, and neurotoxicity were measured using 2',7'-dichlorofluorescin diacetate, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazoliumbromide, and lactate dehydrogenase assays, respectively. EFPA showed conspicuous inhibitory effect on cellular reactive oxygen species production and neuronal cell apoptosis. Finally, kaempferol-3-glucoside was identified as the main phenolic compound of EFPA using high performance liquid chromatography.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.28 no.2
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• pp.109-117
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• 2010

This study conducts a case analysis based on the Olympic Forest Park in Beijing, which is specially designed for the 2008 Beijing Olympic Games. The construction of the Olympic Forest Park not only comprises the design philosophy of city parks and forest parks, but also applies Chinese traditional design elements. This study, first, researches on the design concepts of city parks in the context of traditional landscape architecture elements from both physical and cultural perspectives. The author studies the related materials including the"General Introduction of the Beijing Olympic Forest Park Landscape Plan", and employs the approaches of site investigation and user survey and interview, to analyze the cognition and preference degree of the various traditional design elements displayed in the Olympic Forest Park. To quantize the survey data on the Olympic Forest Park, this study uses the spss(v17.0) software to run a frequency analysis and presents detailed demographic, frequencies and means analyses. The author then reaches the conclusion on the preference degree of the various Chinese traditional design elements in the Olympic Forest Park. According to the analysis result, the elements that appear with the highest frequencies are mountains and waters, traditional garden plants and artistic conception. The most favorable elements are in sequence traditional garden architecture, traditional garden philosophical thinking and artistic conception. The Olympic Forest Park in Beijing is constructed on the basis of multiple design elements, comprising Chinese traditional design elements and the historical axis. As an exemplification of contemporary city park that reflects the variation of age and development of society, the Olympic Forest Park offers the reference for the selection of traditional design elements in the future schemes of city parks. However, due to the difficulty in gathering materials about the Forest Park and the limitations on the location and time constrain of the survey, there exists lack of sufficiency that could be improved in the future.

• Journal of Oral Medicine and Pain
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• v.34 no.2
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• pp.169-177
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• 2009

Recently it is very interesting that the plant extracts use to prevent or treat the oral diseases. The present study was performed to observe the antibacterial effect on S. gordonii Challis, S. gordoii G9B, S. mutans GS5, S. sobriuns 6715, E. faecalis ATCC 4083, A. actinomycetem Y4, P. gingivalis A7A1-28, P. gingivalis W83, Pr. intermedia ATCC 25611, F. nucleatum KTCT 2488, C. albicans ATCC 18804 of Artemisa capillaris THUNB employing the viable cell counts. The results were as follows: 1. Minimum inhibitory concentration(MIC) and Minimum bactericidal concentration(MBC) of extracts of Artemisa capillaris THUNB for P. gingivalis A7A1-28, P. gingivalis W83, and Pr. intermedia ATCC 25611, which are the pathologic bacteria of periodontal diseases, was observed under 2%. 2. MIC of extracts of Artemisa capillaris THUNB for P. gingivalis A7A1-28 was determined to be 1.2% and MBC was determined to be 2.0% respectively. 3. MIC of extracts of Artemisa capillaris THUNB for P. gingivalis W83 was determined to be 1.4% and MBC was determined to be 2.0% respectively. 4. MIC of extracts of Artemisa capillaris THUNB for Pr. intermedia ATCC 25611 was determined to be 1.2% and MBC was determined to be 2.0% respectively. The overall results indicate that Artemisa capillaris THUNB used for this study has a strong antibacterial activity against P. gingivalis A7A1-28, P. gingivalis W83, and Pr. intermedia ATCC 25611, which are the periodontopathic bacteria. Therefore, the extracts of Artemisa capillaris THUNB can be used as a candidate for prevention and therapeutic agent against periodontal diseases.

• Korean Journal of Remote Sensing
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• v.14 no.1
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• pp.53-68
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• 1998

Observation of hydrometeors' behavior in the atmosphere is important to understand weather and climate. By conventional observations, we can get the distribution of water vapor at limited number of points on the earth. In this study, the precipitable water has been estimated from the split window channel data on GMS-5 based upon the technique developed by Chesters et al.(1983). To retrieve the precipitable water, water vapor absorption parameter depending on filter function of sensor has been derived using the regression analysis between the split window channel data and the radiosonde data observed at Osan, Pohang, Kwangiu and Cheju staions for 4 months. The air temperature of 700 hPa from the Global Spectral Model of Korea Meteorological Administration (GSM/KMA) has been used as mean air temperature for single layer radiation model. The retrieved precipitable water for the period from August 1996 through December 1996 are compared to radiosonde data. It is shown that the root mean square differences between radiosonde observations and the GMS-5 retrievals range from 0.65 g/$cm^2$ to 1.09 g/$cm^2$ with correlation coefficient of 0.46 on hourly basis. The monthly distribution of precipitable water from GMS-5 shows almost good representation in large scale. Precipitable water is produced 4 times a day at Korea Meteorological Administration in the form of grid point data with 0.5 degree lat./lon. resolution. The data can be used in the objective analysis for numerical weather prediction and to increase the accuracy of humidity analysis especially under clear sky condition. And also, the data is a useful complement to existing data set for climatological research. But it is necessary to get higher correlation between radiosonde observations and the GMS-5 retrievals for operational applications.