• The Korean Journal of Food And Nutrition
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• v.25 no.3
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• pp.564-569
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• 2012

Selenium was initially considered toxic to humans, but it was then discovered that selenium is essential for normal life processes. Selenium plays important roles in antioxidants. It is expected that chitosan microcapsules containing nano-selenium will be able to be used as a key material in bio-medical and cosmetic applications. The high concentration of chitosan derivatives guarantees increased antioxidative activity. Both inorganic and organic forms of selenium can be nutritional sources. The antioxidant properties of selenoproteins help prevent cellular damage from free radicals. The objective of this experiment was to study the antioxidative activity of chitosan nano-selenium. Our experiments were divided into five groups, in the presence of various concentrations(0.1%, 0.3%, 0.5%, 0.7%, and 0.9%) of chitosan. We performed an assessment of the antioxidant properties and cytotoxicity of respective concentrations of chitosan nano-selenium. The antioxidant activity was examined by the free radical scavenging activity on 1,1-diphenyl-2-picrylhydrazyl(DPPH) assay. The cytotoxicity effect was measured by means of 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay. As a result, the electron donating abilities of 0.1%, 0.3%, 0.5%, 0.7%, and 0.9% of chitosan nano-selenium exhibited effective andioxidant scavenging activity at 12.5 ${\mu}g/m{\ell}$ against DPPH radicals. 0.3% chitosan nano-selenium did not show cytotoxicity on human keratinocytes. In general, the cytotoxicity of 0.1% and 0.9% chitosan nano-selenium showed the lowest effects. Though low cytotoxicity of 0.5% and 0.7% chitosan nano-selenium exhibited 29.67% and 38.4% against human keratinocytes on adding 100 ${\mu}g/m{\ell}$ and 50 ${\mu}g/m{\ell}$, respectively, cell vitality was recovered with 200 ${\mu}g/m{\ell}$. These findings support the notion that chitosan nano-selenium may be useful as a new active ingredient source for bioactive compounds.

• Journal of Korean Home Economics Education Association
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• v.32 no.3
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• pp.161-177
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• 2020

This research aims to identify the relevance of 'Adolescence consumption' units to ESD(Education for Sustainable Development), and to analyze the unit's inquiry tendency through the Romey analysis method. The assessment criteria in association with ESD developed in the previous literature were summarized and established to set up an analysis framework consisted of 11 key points including environmental perspective (natural resources, climate change/disaster prevention and mitigation, and sustainable rural and urban systems), economic perspective (corporate sustainability, market economy, and poverty gap mitigation), and socio-cultural perspective (human rights/peace/human protection, cultural diversity and understanding, health/safety, civic engagement, and management of nation). With this framework, the learning contents of 'adolescence consumption life' unit in twelve middle school Home Economics textbooks were analyzed including the texts, images/illustrations/tables/graphs, and activities. The analysis revealed that the core elements of the 'market economy' and 'management of nation' from the economic perspective were presented in three different formats: texts, images/illustrations/tables/graphs, and activities. However, relatively insufficient contents were presented in terms of health/safety, civic engagement, sustainable rural and urban systems, and corporate sustainability, and thus, development of textbooks dealing with various ESD contents is neededrecommended. Additionally, most textbooks' texts and images/illustrations/tables/graphs tend to be authoritative, while activities and assignments exhibited an inquiry tendency. It is advisable to incorporate a wider variety of ESD-related content in Home Economics classes and creatively employ inquiry-based learning activities for the development of pro-sustainable-development consumption values and behavioral tendencies among young students.

• Journal of the Korean Institute of Landscape Architecture
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• v.38 no.4
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• pp.11-24
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• 2010

The main focus of this research is the establishment of a systemic evaluation model based on objective evaluation indices, which are drawn to assess the experiencing of nature and recreational value at the level of the district unit. First of all, as a result of a literature review, a total of 10 indices can be drawn including vegetation structure, pavement rate, and hemeroby to evaluate an assessment of natural experiences and recreational value. Also, as a result of expert survey analysis, all evaluation index items were above 4.4, which is a high importance average. Hemeroby and unique landscape factor items in particular were above 5.8, which is very high. In addition, as a result of implementing a factor analysis to classify evaluation indices according to characteristics, three factors arise: 'landscape structure and quality of natural experience', 'typical availability', and 'quality of aesthetic and visual sense.' Based on the above survey analysis results, the 'quality of aesthetic and visual sense' was the highest, at 3.510. The classification 'landscape structure and quality of natural experience' was the lowest, at 3.035. A systemic value evaluation model was established by comprehensively analyzing these results. To verify the validity of the evaluation model drawn, real sites are selected and applied. First of all, as a result of a biotope types classification of sites, biotope type groups are classified into a total of 13 including the stream biotope while its subordinate biotope types are classified into a total of 61 groups. Lastly, as a result of biotope value evaluation, which was a previously established evaluation model, there are a total of 16 types including vegetation-abundant natural rivers and small-scale woodlands near forests in grade I. There are 9 types in grade II, 8 in grade III, 8 in grade IV, 19 in the least-valuable grade V.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.2
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• pp.357-367
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• 2018

Recent earthquakes in Gyeongju and Pohang have raised interest in liquefaction in South Korea. Liquefaction, which is a phenomenon that excessive pore pressure is generated and the shear strength of soil is decreased by repeated loads such as earthquakes, causes severe problems such as ground subsidence and overturning of structures. Therefore, it is necessary to identify and prepare for the possibility of liquefaction in advance. In general, the possibility of liquefaction is quantitatively assessed using the Liquefaction Potential Index (LPI), but it takes a lot of time and effort for performing site response analysis which is essential for the liquefaction evaluation. In this study, a simple method to evaluate the liquefaction potential without executing the site response analysis in a downtown area with a lot of borehole data was proposed. In this simple method, the correlation between the average shear wave velocity of the target location ground and the LPI divided by thickness of liquefiable layer was established. And the applicable correlation equation for various rock outcrop accelerations were derived. Using the 104 boreholes information in Seoul, the correlation equation between LPI and the shear wave velocity (ground water level: 0m, 1m, 2m, 3m) is obtained and the possibility of liquefaction occurrence in Seoul and Gyeongju is evaluated. The applicability of the proposed simple method was verified by comparing the LPI values calculated from the correlation equation and the LPI values derived using the existing site response analysis. Finally, the distribution map of LPI calculated from the correlation was drawn using Kriging, a geostatistical technique.

• Journal of Wetlands Research
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• v.16 no.4
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• pp.303-318
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• 2014

Baseflow gives a significant contribution to stream function in the regions where climatic characteristics are seasonally distinct. In this regard, variable baseflow can make it difficult to maintain a stable water supply, as well as causing disruption to the stream ecosystem. Changes in land use can affect both the direct flow and baseflow of a stream, and consequently, most other components of the hydrologic cycle. Baseflow estimation depends on the observed streamflow in gauge watersheds, but accurate predictions of streamflow through modeling can be useful in determining baseflow data for ungauged watersheds. Accordingly, the objectives of this study are to 1) improve predictions of SWAT by applying the alpha factor estimated using RECESS for calibration; 2) estimate baseflow in an ungauged watershed using the WHAT system; and 3) evaluate the effects of changes in land use on baseflow characteristics. These objectives were implemented in the Gapcheon watershed, as an ungauged watershed in South Korea. The results show that the alpha factor estimated using RECESS in SWAT calibration improves the prediction for streamflow, and, in particular, recessions in the baseflow. Also, the changes in land use in the Gapcheon watershed leads to no significant difference in annual baseflow between comparable periods, regardless of precipitation, but does lead to differences in the seasonal characteristics observed for the temporal distribution of baseflow. Therefore, the Guem River, into which the stream from the Gapcheon watershed flows, requires strategic seasonal variability predictions of baseflow due to changes in land use within the region.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.4
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• pp.357-368
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• 2008

On July 31, 2008, the Government issued the construction and operation permit for the first low and intermediate level radioactive waste disposal facility in the Republic of Korea. In this paper, the fundamental regulatory framework, regulatory requirements and technical standards of the disposal facility are introduced, and the phased review process adopted for evaluation of the safety of the facility is briefly described. The Atomic Energy Act sets forth a stepwise regulatory framework for the whole life-cycle of the disposal facility such as siting, design, construction, operation, closure and institutional control. More detailed regulatory requirements and technical standards are stipulated in the subsequent regulations of the Atomic Energy Act and a series of Notices issued by the Ministry of Eduction, Science and Technology. The Korea Institute of Nuclear Safety, as entrusted by the Ministry under the Atomic Energy Act, conducted safety review on the disposal facility, and evaluated the compliance with relevant criteria in all technical elements(i.e. siting and structural safety, radiological environmental impact, operational safety, systems and components, quality assurance, and total systematic performance assessment, etc.). The overall safety review process can be phased into inception phase, initial review phase, main review phase and completion phase. The review results were reported to and deliberated by the five Sub-committees of the Special Committee on Nuclear Safety, and then reported to the Ministry. The Ministry issued the construction and operation permit of the disposal facility through the deliberation of the review results by the Nuclear Safety Commission. Hereafter, the safety of the repository will be reassured by a series of subsequent regulatory inspections and reviews under the Atomic Energy Act. In addition, the licensee's continuous implementation of the "Safety Promotion Plan" may also enhance the long-term safety of the repository and contribute to build-up the confidence of the safety case.

• Journal of Food Hygiene and Safety
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• v.25 no.1
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• pp.49-58
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• 2010

The objectives of this study were to investigate the microbial contamination levels on food service in university and to provide the information of microbial contamination to improve food safety. A total of 288 samples were collected during summer and winter season between 2006 and 2008 from 4 food services located in the university in Western Gyeongnam and were used to detect sanitary indicator bacteria [aerobic plate count (APC), coliform, and Escherichia coli] and pathogenic bacteria (Staphylococcus aureus, Salmonella spp.). As a result, APC and coliform for hand and kitchen utensils which are used often by the employee were detected at high levels of 1.1~5.5 and 1.3~5.3 log CFU/($100\;cm^2$, hand), respectively. The contamination levels of APC and coliform in cooked foods and drinking water were 0.8~6.4 and 1.3~5.0 log CFU/(g, mL), respectively. Especially, the cooked foods showed the highest contamination for APC (2.1~6.4 log CFU/g) and coliform (1.0~5.0 log CFU/g). We think the reason that the cooked foods may be contaminated with APC and coliform on cooking process by using employee's hand and kitchen utensils. Moreover, S. aureus for hand and kitchen utensils was detected at levels of 2.8~3.0 and 2.0~2.3 log CFU/(g, hand), but Salmonella spp. was not detected. According to the above results, contamination levels of the samples were mostly decreased irrespective of summer and winter season. The results obtained indicated that it is necessary to periodic monitoring for microorganism contamination and education about personal and environmental hygiene to employee for ensuring food safety of food service in university.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.4
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• pp.307-316
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• 2010

Complex terrain refers to irregular surface properties of the earth that influence gradients in climate, lateral transfer of materials, landscape distribution in soils properties, habitat selection of organisms, and via human preferences, the patterning in development of land use. Complex terrain of mountainous areas represents ca. 20% of the Earth's terrestrial surface; and such regions provide fresh water to at least half of humankind. Most major river systems originate in such terrain, and their resources are often associated with socio-economic competition and political disputes. The goals of the TERRECO-IRTG focus on building a bridge between ecosystem understanding in complex terrain and spatial assessments of ecosystem performance with respect to derived ecosystem services. More specifically, a coordinated assessment framework will be developed from landscape to regional scale applications to quantify trade-offs and will be applied to determine how shifts in climate and land use in complex terrain influence naturally derived ecosystem services. Within the scope of TERRECO, the abiotic and biotic studies of water yield and quality, production and biodiversity, soil processing of materials and trace gas emissions in complex terrain are merged. There is a need to quantitatively understand 1) the ecosystem services derived in regions of complex terrain, 2) the process regulation occurred to maintain those services, and 3) the sensitivities defining thresholds critical in stability of these systems. The TERRECO-IRTG is dedicated to joint study of ecosystems in complex terrain from landscape to regional scales. Our objectives are to reveal the spatial patterns in driving variables of essential ecosystem processes involved in ecosystem services of complex terrain region and hence, to evaluate the resulting ecosystem services, and further to provide new tools for understanding and managing such areas.

• Journal of Dairy Science and Biotechnology
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• v.34 no.4
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• pp.255-262
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• 2016

This study was conducted to investigate the difficulties of dairy farms in practicing 6th industrialization and methods for overcoming these difficulties. A qustionnaire survey was carried out to examine the present states of farms, recognition of the farmstead milk-processing market situation, possibility of farmstead milk processing for reducing the raw milk surplus, assessment of government policies, and difficulties dairy farmers confront in realizing the 6th industrialization. Farm sizes, types, and human resources organizations varied between farms. Most farmers were producing yogurt and/or fresh (string or barbecue) cheeses, which were marketed through 'Visit and Purchase' channel. Farmers who answered the questionnaire were relatively positive about the current situation of farmstead milk processing, expecting to be involved in the disposal of excess raw milk. Nevertheless, they responded negatively about current relevant policies, citing the main difficulties caused by 'excessive regulation'. Other barriers to successful '6th industrialization' are difficulties in marketing and lack of funds. Approximately 19% of dairy farms practicing the '6th industrialization' use automatic milking system (AMS) and 38.46% of dairy farmers whose milking depends on conventional milking system intend to introduce AMS in the future. Positive expectations of AMS adoption were mostly related to 'lack of time and labor', 'exhibiting for tourism', and 'succession of dairying'.

• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.2
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• pp.132-142
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• 2010

Characteristics of meteorological elements were analyzed at Hwagae and Agyang where are the representative areas of Hadong green tea cultivation in Korea. An automatic weather monitoring system (AWS) and a simple data log were employed to measure meteorological data such as temperature, relative humidity, precipitation, and wind direction and speed for 2009. The annual average air temperature of Hwagae and Agyang was 14.5 and 14.2, respectively, showing the warmest month in August ($25.4^{\circ}C$ for Hwagae and $24.9^{\circ}C$ for Agyang) and the coldest month in January ($0.3^{\circ}C$ for Hwagae and $0.2^{\circ}C$ for Agyang). Annual average of daily temperature difference (= daily maximum temperature - daily minimum temperature) was $11.3^{\circ}C$ for Hwagae and $11.1^{\circ}C$ for Agyang. Hwagae and Agyang had 62.7% and 65.3% of the annual average relative humidity, respectively. Annual precipitation was 1387 mm for Hwagae and 1793 mm for Agyang of which were higher of 605mm for Hwagae and 835 mm for Agyang compared to that in 2008. Majority of precipitation occurred between May and August, attributing 77.6% for Hwagae and 76.6% for Agyang to the annual precipitation. The annual total sunshine duration was 2054.3 hrs in Hwagae with the longest monthly sunshine duration in May (235.1 hrs) and the shortest monthly sunshine duration in July (102.5 hrs). Dominant wind direction changed seasonally from northwesterly wind in fall and winter to southeasterly wind in spring and summer. The annual average wind speed was 1.5 m $s^{-1}$ with the highest monthly wind speed of 2.0 m $s^{-1}$ in December and the lowest monthly wind speed of 1.1 m $s^{-1}$ in February. It is expected that continuous observation and assessment of meteorological data will improve our understanding of optimal environmental conditions for green tea cultivation and be used for developing models of green tea cultivation in the Hadong area.