• Korean Journal of Environmental Agriculture
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• v.16 no.4
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• pp.295-303
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• 1997

To investigate the transformation characteristics of nitrogen and carbon from cow manure compost amended in soil under different moisture conditions, dynamics of nitrogen and carbon were determined periodically for 15 weeks of aerobic incubation at room temperature during July${\sim}$November, 1996. Cow manure compost matured with mixing saw dust was amended with the 4 ratios (0, 2, 4, 6%(wt/wt)) in Ap horizon soil, which collected from green house in Yesan, Chungnam. Moisture was controlled with 0.2, 0.3, 0.4, and 0.5 of mass water conte nt (${\theta}$m) to air dried soil, and water loss was compensated at every sampling. During incubation, soil pH was decreased continuously, that was caused by hydrogen generated from nitrification of ammonium nitrogen. And pH became higher with inclining cow manure compost amendment and water treatment, that meaned the increase of mineralization of organic-N to $NH_4\;^+-N$. Total nitrogen was reduced with increasing water content, but total carbon showed the contrast tendency with that of nitrogen. Therefore, C/N ratio slightly decreased in the low water condition (${\theta}$m 0.2) during incubation, but increased continuously in high water condition over ${\theta}$m 0.4. As a result, it was assumed that soil fertility is able to be reduced in the high water content over available water content. Nitrate transformation rate increased lasting in the low water content less than ${\theta}$m 0.3. Itdropped significantly in the first $2{\sim}3$ weeks of incubation over ${\theta}$m 0.4. In particular, nitrate was not detected in ${\theta}$m 0.5 of water content after the first $2{\sim}3$ weeks. In contrast, ammonium transformation was inclined with increasing water treatment. Nitrogen mineralization rate, which calculated with percentage ratio of (the sum of ex.$NH_4\;^+-N$ and $NO_3\;^--N$)/total nitrogen, was continuously increased in the low water content of ${\theta}$m 0.2 and 0.3. But it saw the different patterns in high water content over ${\theta}$m 0.4 that was drastically declined in the initial stage and then gradually inclined . From the above results, nitrogen transformation patterns differentiated decisively in water content between ${\theta}$m 0.3 and 0.4 in soil. Thus, it is very important for the maintain of suitable soil water content to enhance fertility of soil amended with manure compost. However, excess treatment of manure compost might enhance the possibility of contamination of small watershed and ground water around agricultural area.

• Journal of Animal Environmental Science
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• v.18 no.2
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• pp.111-122
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• 2012

Establishment of the LFQC (Liquid Fertilizer Quality Certification) system is very urgent issue for recycling livestock manure as renewable resources in Korea faced with environmental problem of manure application to land due to intensive livestock farming. In this study, we investigated relevant laws and regulations on livestock manure fertilizer, certifications of eco-friendly agricultural products, government policies on livestock manure management to establish reasonable direction of Korean LFQC (Liquid Fertilizer Quality Certification) system. As a result from this study, the liquid fertilizers in 'LFQC' system could be classified as three levels according to the usage patterns in field; 1st. Individual Farm Level (IFL), 2nd. Joint Farm Level (JFL), and 3rd. Commercial Level (CML). And finally, we found some characteristics in 'Main Level-Grading Factors' of liquid fertilizer such as fertilizing value, harmfulness, stability, uniformity, economic effect, storage potential, commercial value, functionality. Those items were considered to be the key factors for the establishment of 'LFQC' system. More research on 'Evaluation Standards' for concrete guideline and on the 'Main Level-Grading Factors' be needed to complete Korean LFQC system.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.34 no.4
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• pp.14-25
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• 2016

This study aims to investigate what flowering plant Jeongjo loved, the attitudes and the reasons, and their implications. The study method was to investigate the contents and meaning in the historical records and to describe their interpretation. Jeongjo's life was consistent with very abstinent life style. His food, clothing and shelter were simple, and he did not show the interests in music, various arts and craft, women, and so on. He did not even show his interest in the flowers and plants of fairyland, beautiful flowers and plants. Jeongjo knew various kinds of flowers, and he was proficient in artistic expressions such as literature or painting with flower material. Due to this kind of attitude, there were few cases to demonstrate his taste on the specific flowering plant. The only one that Jeongjo revealed as his favorite flower was the pomegranate. However, the pomegranate was not the simple flowering plant as the subject of enjoying to Jeongjo. The pomegranate has the meaning of indicator plant to indicate the season of rice farming. Therefore, he made it to be the intermediary to indicate the farming season, which counted a few. Besides, Jeongjo who was threatened by the trials of assassination to him in his early throne period utilized 5,600 pomegranate flowerpots as the barricade of his shelter by arraying them with the type of stone piles in $B{\bar{a}}zh{\grave{e}}nt{\acute{u}}$(八陣圖). The use of Jeongjo's pomegranate flowerpots was not related to the visual utilization like ornament at all, which was very unique case. From multiple records, it was found that the pomegranate was the flower to be with Jeongjo in his period of reign. It is remarkable that the reason why Jeongjo kept pomegranate for a long time like this had the difference from enjoying practice on the ordinary flowering plant. This study has the limitation to be conducted depending on the Korean translated data. Further studies are required according to the translation performance of new historical records.

• Korean Journal of Social Welfare Studies
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• v.49 no.2
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• pp.125-157
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• 2018

In the reality that the seriousness and concern about the youth problem is increasing, this study focuses on the vision plan project supporting the NEET youth in the social welfare field. Therefore, this study analyzed how the social workers recognized the NEET problem before participating in the project, what difficulties they experienced in the process of the project, and how they coped with these difficulties. The results of the study are as follows. Social workers were saddened by the seriousness of the youth problem before their participation, but they recognized that there was no way to solve it and many social workers were not fully aware of the youth or NEET issues. In this context, in the course of running a project with NEET youth, social workers experienced difficulties due to the nature of the NEET youth, difficulty in forming a relationship with NEET youth, and difficulties for young people not to spend time in the program. And social workers also faced difficulties due to the lack of know-how in the project, difficulties in operating the center alone, and difficulty in achieving employment goals. In the process of coping with these difficulties, social workers have actively sought, persuaded and supported the NEET youths to participate in the project, adapted the time, place and method to the youth, and removed the stigmatization element in the project. They also worked closely with local residents, local institutions and municipalities, formed networks, and changed the viewpoint of providing work experience rather than getting young people, but seeing long-term outcome. As a result, social workers have experienced not only individual change but also social welfare organization, field, community and local institutional change. Based on these results, this study suggested that the social welfare practice field should provide various activities in the process of supporting the youth gap year policy. In addition, this study suggests that the social workers play a role in connecting various actors rather than suppliers when working with young people, and that the social welfare field should expand the scope of project to include youth.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.2
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• pp.101-107
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• 2005

To investigate the effect of pyroligneous acid liquor (PAL) on the maturity of pig manure compost, PAL was treated to the compost piles. The treatments included applications of 100 and 300 times diluted PAL in addition to the control. The compost piles were stirred in three times at the 1st, 10th, and 25th day of composting. Temperature in the compost pile of control treatment increased from 28 to $60^{\circ}C$ within 10 days and remained nearly at the level until 30th day, then it began to decrease. On the other hand, temperature of the PAL-100 and PAL-300 treatments reached 65 to $70^{\circ}C$ within 8 days and became stabilized until 30th day, then the temperature decreased to about $28^{\circ}C$. However, the temperature of control was stabilized approximately at the 40th day. Initially, the pH of control treatment dropped from 8.2 to slightly above pH 8.0 during 4th day, but that of the PAL-100 treatment declined to 7.8. Among treatments, pH value of PAL-100 treatment was the lowest, which was about 7.3 after becoming stabilization. Also the germination index (GI) was increased at all treatments. The C/N ratio range of PAL-100 treatment was better balanced than others and was at 24.3. Moreover the round paper chromatogram of extracted solution of compost of PAL-100 treatment was the sharpest and clearest among treatments. The GI values of control, PAL-100, and PAL-300 in 60 days of composting were about 108, 120, and 118 in germination test using chinese cabbage, respectively. It can be concluded that the addition of diluted PAL solution is effective in composting of pig manure.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.347-352
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• 2011

Environment-friendly agriculture (EFA) are aimed to reduce use of chemical inputs as possible the recycling of resources and the environment while preserving the local resources in the long term to ensure a constant productivity and profitability for producing safe food. This study was conducted to investigate characteristics on soil environment at paddy field of environment-friendly agriculture regions (EFARs) in Honam area. Survey point of EFARs Chungnam, Jeonbuk and Jeonnam, rice bran farming method in two districts, rice bran + snail farming method in eight districts, snail farming method in five districts and ducks farming method in three districts a total of 18 districts were selected. Annual of farming method, friendly-environment certification, amount of applied fertilizer, and history of cultivation to the farm household were surveyed. The content of available phosphate and silicate among the soil chemical properties in EFA paddy field were a little lower than optimum level, and those of agricultural methods fertilized with rice bran were a little lower than those of others. Hardness among the soil physical properties in EFA paddy field were a little lower than conventional practices, and that of agricultural methods fertilized with rice bran were a little lower than those of others. We showed fertilizer recommendation dose about soil nutritional shortages according to fertilization prescriptions index by crops.

• Journal of Korean Society of Forest Science
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• v.110 no.3
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• pp.406-418
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• 2021

This study was conducted to evaluate optimal storage techniques for bare root plants and container seedlings of Quercus variabilis and Zelkova serrata in order to maintain high quality of seedlings until planting. Refrigerated storage treatments were given at two temperatures (-2℃ [freezing] and 2℃ [cooling]) for nine different durations (0, 15, 30, 60, 120, 180, 240, 300, and 360 days after storage). We analyzed total nonstructural carbohydrate (TNC) content and measured shoot moisture content (SMC) during the storage stage and survival rate (SR) and dry weight during the planting stage of seedlings. The TNC content and SMC of the seedlings of the two species decreased with an increase in storage duration. The TNC content of seedlings rapidly decreased after 180~240 days of storage. The TNC reduction rate in the freezing treatment was lower than that in the cooling treatment. Also, with an increase in the storage duration of the two species, the SMC reduction rate in the cooling treatment increased in comparison with that in the freezing treatment. In both the species, the SR after planting decreased rapidly after 60 days of cooling storage and 180 days of freezing storage, respectively. The SR after planting was less than 60% when the TNC content for both the species dropped below 20 mg g^-1. In addition, the SR was lower than 80% when SMC measured before storage decreased by approximately 30% and 20% for Q. variabilis and Z. serrata, respectively. Our results suggest that cooling (1~2℃) storage is recommended for a short-term period (2 months or less), whereas freezing (-2~-4℃) storage is suitable for longer periods (2~6 months). These optimal storage techniques, allied with seedling harvesting and handling systems, will improve the quality of seedling production in nursery stages and increase seedling growth performances in plantations.

• Journal of Korea Port Economic Association
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• v.36 no.4
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• pp.17-30
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• 2020

In the shipping industry, it is essential to engage in the preemptive prediction of freight rate volatility through market monitoring. Considering that freight rates have already started to fall, the loss of shipping companies will soon be uncontrollable. Therefore, in this study, factors affecting the freight rates of bulk carriers, which have relatively large freight rate volatility as compared to container freight rates, were quantified and analyzed. In doing so, we intended to contribute to future shipping market monitoring. We performed an analysis using a vector error correction model and estimated the influence of six independent variables on the charter rates of bulk carriers by Handy Size, Supramax, Panamax, and Cape Size. The six independent variables included the bulk carrier fleet volume, iron ore traffic volume, ribo interest rate, bunker oil price, and Euro-Dollar exchange rate. The dependent variables were handy size (32,000 DWT) spot charter rates, Supramax 6 T/C average charter rates, Pana Max (75,000 DWT) spot charter, and Cape Size (170,000 DWT) spot charter. The study examined charter rates by size of bulk carriers, which was different from studies on existing specific types of ships or fares in oil tankers and chemical carriers other than bulk carriers. Findings revealed that influencing factors differed for each ship size. The Libo interest rate had a significant effect on all four ship types, and the iron ore traffic volume had a significant effect on three ship types. The Ribo rate showed a negative (-) relationship with Handy Size, Supramax, Panamax, and Cape Size. Iron ore traffic influenced three types of linearity, except for Panamax. The size of shipping companies differed depending on their characteristics. These findings are expected to contribute to the establishment of a management strategy for shipping companies by analyzing the factors influencing changes in the freight rates of charterers, which have a profound effect on the management performance of shipping companies.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.1
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• pp.187-198
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• 2019

The purpose of this study is to seek ways of utilizing TLBMC by understanding business model of social ventures that are accompanied by social and environmental as well as economic missions. In order to achieve this, business models from economic, environmental and social perspectives will be analyzed, and we seek to enhance sustainability of social venture entrepreneurs. As the analysis tool, TLBMC(Triple Layered Business Model Canvas) expands upon the business model canvas that is widely utilized and recognizes economical terms. The TLBMC is proposed by Joyce, A., & Paquin, R. L.(2016) to help achieve a holistic view with horizontal and vertical associations. The study tries to overcome limitations of previous studies and observe a variety of economic, environmental, and social perspectives that social ventures should have with the TLBMC. As a result, it has the following implications; Firstly, creating separate social, environmental and economic business model canvas helps a business to have a holistic approach. Secondly, it was found that social venture characteristics of environmental and social perspectives were applied in practice. Lastly, we have established experience data on social venture business model. This study focuses on the opinions, the meanings and the subjective views of the participants. As a result, conclusions are drawn by the researchers ' assertions and has limitations as a research on case studies. However, this study will help people who are preparing or studying social ventures to have economic, environmental, and social perspectives. Also, redefinition of the direction and value of entrepreneurs operating social ventures, such as vision and mission, will help clarify the roles and responsibility of organizations. As a fundamental step for future empirical studies, this study could be the base for social venture business model studies.

• Journal of Life Science
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• v.29 no.6
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• pp.688-696
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• 2019

This study investigated changes in triglyceride and cholesterol synthesis and tyrosinase activity induced by ice plant (Mesembryanthemum crystallinum L.) extract, which cannot be stored for long periods of time due to its high moisture content when it was fermented to improve its storage stability. The accumulation of triglyceride and cholesterol in HepG2 cells inhibited the accumulation with a relatively large magnitude in n-butanol and aqueous fractions that generally have high polarity, however, changes in inhibition potency due to the fermentation were not significant. As for the effect to inhibit tyrosinase activity, when L-tyrosine was used as a substrate, the inhibitory activity was the highest for the aqueous fraction at $60.58{\pm}4.03%$ and $63.35{\pm}4.35%$, before and after fermentation, respectively, which amounted to 72% of that of the positive control group (arbutin, $100{\mu}g/ml$). In addition, when L-3,4-dihydroxyphenylalanine (L-DOPA) was used as a substrate, the inhibitory activity was also found the highest for the aqueous fraction at $56.85{\pm}1.57%$ and $59.38{\pm}1.74%$, before and after fermentation, respectively, which amounted to at least 88% of that in the positive control (kojic acid, $100{\mu}g/ml$). Overall, the activity of the fermented ice plant extract was similar or a little higher compared to that of the one without fermentation, indicating that fermentation can be a good approach to improve the storage stability of the ice plant.