• Korean Journal of Environmental Agriculture
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• v.38 no.3
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• pp.119-123
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• 2019

BACKGROUND: Estimation of soil nitrogen supply is essential to manage nitrogen fertilization in arable land. In Korea, nitrogen fertilization is recommended based on the soil organic matter content because it is difficult to assess nitrogen (N) mineralization of upland soils directly. In this study, the relationship between soil organic matter (SOM) content and N mineralization was investigated to explore the limitation of using SOM in predicting soil N mineralization. METHODS AND RESULTS: Soil samples from the 0 to 10 cm depth were collected from 18 individual pepper cultivated fields in Tae-an and Chung-yang provinces before fertilization. N mineralization in the soils was quantified using incubation for 70 days at $30^{\circ}C$. The mineralizable soil N (MSN) was positively correlated with SOM, and the relation equation between MSN and SOM was '$MSN(kg\;10a^{-1})=0.2933{\ast}SOM(g\;kg^{-1})+0.0897$ ($r^2=0.6224$, p<0.001)'. However, the differences of N mineralization among the soils with the similar concentrations of soil organic matter were about 3 to 4.6 times, suggesting that the other soil factors such as total N concentration or EC should affect N mineralization. CONCLUSION: We concluded that SOM alone could not reflect the capacity of soil to supply N that is used for recommendation of N fertilization rate. Therefore, other soil properties should be considered to improve N fertilization management in arable land for sustainable agriculture.

• Economic and Environmental Geology
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• v.54 no.4
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• pp.427-439
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• 2021

On the base of the aggregate extraction statistics, this study tried to analyse the demand and supply of aggregate resources of each local government and provide directions for the stable and sustainable supply and demand of aggregate resources in the future. In 2019, aggregates were produced in 148 cities, about 65% of the 229 cities of Korea, but in 7 metropolitan cities with 74 local governments, only 19 cities developed the aggregate. It means that aggregate extraction is taking place in almost all regions in Korea. Sand and gravel were produced in 110 districts and 132 districts, respectively. By aggregate source, river aggregates were extracted in 4 local governments, land aggregates in 42 local governments, forest aggregates in 75 local governments, crushed aggregates in 105 local governments, and washing aggregates in 15 local governments. In other words, 81 district in Korea have not extracted land-based aggregate at all. 71 local governments produced only one type of aggregate, and 55 local governments developed two types of aggregate, and 22 local governments developed more that three types of aggregate. In 2019, the leading producing local government were, in descending order of volume, Ulju-gun, followed by Hwaseong-si, Cheongju-si, Pocheon-si, Paju-si, Yongin-si, Gimhae-si, Gwangju-si in Gyeonggi-do. 41 local governments have developed aggregates of more than 1 million m³, and the combined production of the 41 cities accounted for about 70% of national total. This shows that the aggregate extraction trend of local governments is becoming larger and more concentrated.

• Korean Chemical Engineering Research
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• v.61 no.4
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• pp.496-504
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• 2023

Countries worldwide are striving to find new sources of sustainable energy without carbon emission due to the increasing impact of global warming. With the advancement of the fourth industrial revolution on a global scale, there has been a substantial rise in energy demand. Simultaneously, there is a growing emphasis on utilizing energy sources with minimal or zero carbon content to ensure a stable power supply while reducing greenhouse gas emissions. In this comprehensive overview, a comparative analysis of carbon reduction policies of government was conducted. Based on international carbon neutrality scenarios and the presence of remaining thermal power generation, it can be categorized into two types: "Rapid" and "Safety". For the domestic scenario, the projected power demand and current greenhouse gas emissions in alignment with "The 10th Basic Plan for Electricity Supply and Demand" was examined. Considering all these factors, an overview of the current status of carbon neutrality technologies by focusing on the energy sector, encompassing transitions, hydrogen, transportation and carbon capture, utilization, and storage (CCUS) was offered followed by summarization of key technological trends and government-driven policies. Furthermore, the central aspects of the domestic carbon reduction strategy were proposed by taking account of current mega trends in the energy sector which are highlighted in international scenario analyses.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.137.2-137.2
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• 2010

With current real economic growth of more than 10% per year, the Chinese energy consumption is rapidly increasing. Coal supply consists of the vast majority of China's total energy consumption requirements in 2008. China, the largest energy consumer, is expected to be heavily dependent on coal for future power generation, too (IEA,2009). A growing concern on global warming, on the other hand, drives Chinese government to declare her commitment to the reduction of CO2 emission by 2020. In this paper, China's energy market is examined for the current and future primary energy mix. Coal is found to be the biggest part accounting for 68.7% of total primary energy consumption while coal-fired power accounts for over 80% of the total power generation. The importance of Clean Coal Technology is being discussed based on the findings of the importance of coal in China's economy and its sustainable development. Among the technologies involved, a brief investigation of IGCC(Integrated Gasification Combined Cycle) technology with a review on current IGCC projects in China are provided from the perspective of environmental benefits. Studies on regional Chinese power market is also conducted. It is found that the regulated power tariff in electricity system makes the power suppliers suffer from financial loss and changes in the electricity price system is under serious consideration by Chinese government. Even though Chinese power market system causes difficulties of commercialization for IGCC technology, the potential benefits will be high due to China's huge requirements of power generating capacity and its heavy reliance on coal if the electricity price system can be changed smoothly.

• Journal of Forest and Environmental Science
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• v.29 no.1
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• pp.15-28
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• 2013

Protected area based ecotourism is now the most interesting topic to the nature lover and policy maker throughout the world because of its linkage with economic benefits, protected area management and biodiversity conservation. Based on this premise our study explores the visitors' perception on the recreational potential of Kaptai National park and its potentiality in ecotourism development in Bangladesh. The field survey was carried out both in holidays and non-holidays of the week from the late winter season in 2009 to the spring season in 2010. A total of 118 visitors were interviewed with the help of a semi-structured questionnaire. Study findings revealed that about 62% male constitute the visitors group with the maximum number of visitors in the age of between 15-25 years (35.59%). The tourists were very much attracted by boat riding (93.22%) followed by scenic beauty of Rampahar-Sitapahar (85.59%). A major portion of about 57.14% tourists wished to visit the park within a year because they got a lot of pleasure from Natural and green environment (86.44%) followed by boating on Kaptai Lake (85.59%). Most of the visitors (36%) were happy about existing facilities but defined some problems such as tour guiding facility, food and drinking water supply, etc. About 71% and 66% respondents perceived that Kaptai National Park made them to be concerned and protective of nature and supports and sustains local ecosystem respectively and 43% respondents agreed that Kaptai National Park ensures the social equity and involve local people in ecotourism which are the most important elements of sustainable ecotourism. The present study results also predict that the park might be a good recreational area for enjoying with family members and group of friends through proper management and promoting the relationships among tourism, local people and biodiversity conservation.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.7
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• pp.951-960
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• 2018

Hanwoo cattle are an important food source in Korea and their supply can have a major impact on meat availability for Korean consumers. The Hanwoo population was 1.8 million head in 2005 and gradually increased to 2.6 million in 2015. Per capita beef consumption has also increased, to 11.6 kg per year in 2015, and is expected to continue to increase. Because intramuscular fat percentage is a critical contributor to meat quality, Hanwoo cattle are fed a high-energy corn-based diet for long fattening periods. Long fed diet causes significant alterations in fat percentage in the loin muscle and other areas of the carcass. However, these long feeding periods increase feeding costs and beef prices. Recently, there has been increased Korean consumer demand for lean beef which has less fat, but is tender and priced more reasonably. These consumer demands on the Korean beef industry are driving differing beef production systems and also changes to the beef grading methodology. Korean government has made a significant investment to select bulls with favorable production traits using progeny testing. Progeny tested bull semen has been disseminated to all Hanwoo farmers. A beef traceability system has been employed for all cattle breeds in Korea since 2009. Hanwoo cattle are ear-marked with a 12-digit identification number from birth to slaughter. This number allows traceability of the management history of individual cattle, and also provides information to consumers. Traceability including management information such as herd, farm, year of birth, and carcass data can determine estimated breeding values of Hanwoo. For a sustainable Hanwoo industry, research scientists in Korea have attempted to develop feeds for efficient fattening periods and precision feeding systems based on genetic information for Hanwoo cattle. These initiatives aim to Korean consumer demands for beef and provide more precision management in beef production in Korea.

• Korean Journal of Construction Engineering and Management
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• v.4 no.4 s.16
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• pp.96-105
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• 2003

Technical improvement and the growth of the Internet environment make the market segmental of the manufacturing industry. These social trends have had an effect on the housing market, and the housing market changed from the supplier-oriented to the consumer-oriented. In recent years the occupants' needs for the apartment is diversified and complicated. But the existing mass housing supply method has many problems. It couldn't satisfy the dwellers' various needs and couldn't reflect overall expected life span either. In order to realize the sustainable building & environment, the research for the open housing system is actively performed. Finally the custom-built apartment which imported the concept of the open housing is constructed. But after running the custom-built apartment, several problems are revealed. Therefore the purpose of this study is to analyze the problems and then suggest the improving methods for a custom-built apartment.

• Membrane Journal
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• v.24 no.2
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• pp.88-99
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• 2014

Demand for water is increasing due to rapid population growth and increased industrial activities. Membrane technologies have attracted most attention as a promising advanced technology for the supply of sustainable water resources. Chemical and structural properties of polyamide membranes, one of the most widely used membranes in water treatment plant, has been reported to be affected by residual chlorine dissolved in water after chlorine disinfection. This paper focuses on the chlorine speciation at various solution pHs and change of surface properties/performance of polyamide membranes due to the chlorine exposure.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.5
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• pp.1079-1085
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• 2012

Many researchers worldwide have been making a lot of effort to find sustainable clean energy source to replace the current fossil fuels. However, solar energy is considered as the ultimate energy solution to supply the world total power consumption. Light can be used for lighting, heating, wired and wireless communications, etc. Moreover, even light-driven motors which can directly convert optical energy into kinetic energy are studied recently. In this paper, we analyze optical energy delivery through multi-core optical fibers. Our estimation shows that an optical power of 2 kW can be transmitted through a multi-core fiber and an optical power of >10 MW can be transmitted through a bundle of optical fibers with a diameter of several centimeters. It seems competitive compared with the electric power delivery through a copper cable.

• Journal of Korean Society of Rural Planning
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• v.13 no.3
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• pp.103-110
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• 2007

Land development policy in Korea, characterized by its supply-oriented policy, has driven rapid economic development. However, it has a negative impact on the natural environment across the country. Especially, as the introduction of quashi-farmland system with the deregulation of agricultural land development in the late 1990s, numerous unfavorable landscape features such as road, motels and apartment have emerged in the rural area. As those interfered irreversible rural landscapes have been expanded, the demand for well preserved rural landscapes have been increased. The objectives of this study, thus, is to suggest the mitigations between the land development and conservation of natural landscape. As such, this study examines the recognition of current rural landscape management status through 118 students with two groups of landscape architecture majored (50 people) and non-landscape majored (68). Both group express the negative impression of current rural landscape management system in general and they pointed out the major landscape problems are caused from inappropriate land use. However, in detail those two groups respond differently, for example, the first group selected the damaged landscape is the second cause of the landscape problem, while the other group selected the poorly maintained settlements. Based on the analysis of the survey, this study suggests 3 recommendations in order to improve the sustainable rural landscape as establishing the proper rural land use planning system, building local governments' capacity to actively participate in the rural landscape management, and preparing the landscape management plans considering area distinctive characteristics.