• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.6
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• pp.485-492
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• 2008

To propose proper vessel characteristics for sustainable fisheries in Korean waters, we analyzed the fishing capacity, scale efficiency and utilization of large pair-trawl vessels based on the database of catch, effort and vessel characteristics (gross tonnage and engine power) in 1990 by applying data envelopment analysis (DEA). The input factors were gross tonnage, horse power and days operated; whereas the output factor was expected catch by vessel characteristics. The optimal vessel types, selected based on the input-oriented technical efficiency and gross tonnages, was 100 GT with engine power <600 HP. The output-oriented unbiased estimate of capacity utilization (CD) decreased with increasing vessel tonnage. For the same tonnage vessels, the CD decreased with increasing engine power.

• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.269-274
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• 2008

Nowaday, The Sustainable Development about global environment is the most important subject. In urban environment, a variety of the nature energy utilization such as the solar energy are the most efficient solution to solve this issue. One of these efficient, solutions, a photovoltaic system using sunlight has been introduced to the building with an advantage such as cost-effective, safe for using and good for environment friendly in light with energy utilization. Recently, many of the apartment housings are built in domestic country. The apartment buildings have been constructed since early of 1970's. now apartment is taking over 50% out of entire housing in korea. The apartment housing applying to a photovoltaic system has been extensively studied in the foreign country but our county runs short. So, It was necessary to technical development of PV application which is suitable in Korean house culture. The objective of this study is to develop the building integrated PV application method for apartment building.

• Journal of Industrial Technology
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• v.26 no.A
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• pp.189-197
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• 2006

Water shortage as well as water control problems including urban flood and drought have led to developing technologies for rainwater utilization in order to provide a sustainable water supply. However, relatively few works have been done to improve the water quality during rainwater utilization. Therefore, in this study, the characteristics of rainwater were examined in terms of pollutant concentrations and outflow rate. A experimental rain and roof model($1m{\times}1m$) were produced to evaluate wash-off properties of pollutants. And rainfall intensity were standardized in 10 mm/hr, a experimental model roof catchment surface were coated in $TiO_2$ photocatalyst. Samples of runoff rainwater collected from a experimental model were analyzed for physicochemical parameters such as Turbidity, Suspended Solid, EC. The results show that the first flush of rainwater contains substantial amount of contaminants that potentially pollute the whole rainwater. Surface treatment of roof catchment area using $TiO_2$ photocatalyst allowed a better runoff property of rainwater because of its improved hydrophilicity.

• Advances in concrete construction
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• v.9 no.6
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• pp.589-596
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• 2020

In an effort to find alternate, environment friendly and sustainable building materials, the scope of possible utilization of iron slag (I-sand), generated as a by-product in iron and steel industries, as fine aggregates in reinforced cement concrete (RCC) made with manufactured sand (M-sand) is examined in this manuscript. Systematic investigations of the physical, mechanical, microstructural and durability properties of I-sand in comparison with RCC made with M-sand have been carried out on various mix designs prepared by the partial/full replacement of I-sand in M-sand. The experimental results clearly indicate the possibility of utilizing iron slag for preparing RCC in constructions without compromising on the property of concrete, durability and performance. This provides an alternate possibility for the effective utilization of industrial waste, which is normally disposed by delivering to landfills, in building materials which can reduce the adverse environmental effects caused by indiscriminate sand mining being carried out to meet the growing demands from construction industry and also provide an economically viable alternative by reducing the cost of concrete production.

• Knowledge Management Research
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• v.16 no.1
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• pp.21-54
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• 2015

A bunch of management studies have repeatedly revealed that the extent of knowledge sharing across organization contributes significantly to the firm's sustainable competitiveness. However, in reality, it is a hard fact that we must admit that many individuals working in competitive situations always feel reluctant to share knowledge. Especially, positive and negative emotions play an important role in changing individual' s intentions about knowledge sharing and knowledge utilization as well. Intention about knowledge sharing is usually hindered by in-group rivalries. Also employees feel negative in sharing their knowledge with colleagues when they expect to receive little support and recognition in return after doing that. These considerations point out the importance of individual's knowledge sharing and the role of knowledge management in order to assure competitiveness. Considering these facts, the main purpose of this study is to investigate why people is willing or unwilling to share their knowledge with others and utilize the knowledge in the competitive context where potential rivalry is still expected. In answering these research issues, we analyzed 258 valid questionnaires garnered from online community where a number of people has been actively interacting with registered members to share crucial knowledge about sensitive issues. Results revealed that the proposed research issues are adequately solved with significant statistical results.

• KIPS Transactions on Software and Data Engineering
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• v.9 no.8
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• pp.235-242
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• 2020

In order to promote digital transformation of our agricultural and rural communities in the wake of the fourth industrial revolution and prepare for the upcoming artificial intelligence era, it is necessary to establish a system and system that can collect, analyze and utilize necessary quality data. To this end, we will investigate and analyze problems and issues felt by various stakeholders such as farmers and agricultural officials, and present strategic measures to revitalize big data, which must be decided in order to promote digital transformation of our agricultural and rural communities, such as expanding big data platforms for joint utilization, establishing sustainable big data governance, and revitalizing the foundation for big data utilization based on demand.

• Journal of Energy Engineering
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• v.15 no.2 s.46
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• pp.96-106
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• 2006

Among several different hydrogen production technologies, solar hydrogen system for water splitting is the only clean and sustainable energy supplier. Hydrogen production by water-splitting utilizing solar energy has attracted considerable interest since the pioneering work of Honda and Fujishima in 1979, who discovered that water can be photo-electrochemically decomposed into hydrogen and oxygen using a semiconductor ($TiO_2$) electrode under UV irradiation. Most efforts to utilize solar ray lead to explore visible responding photocatalysts, PEC cells and other fusion technology like bio-photocatalytic conversion. In this paper, photon utilization technologies for water splitting have been briefly reviewed except solar thermal utilization technology.

• Journal of Korean Society of Rural Planning
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• v.25 no.1
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• pp.11-20
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• 2019

The purpose of this study was to analyze the status of conservation and management of KIAHS(Korea's Important Agricultural Heritage System) by focusing on which of the conceptual and institutional characteristics and stakeholder activities, and to suggest improvement plans. The results were summarized as follows, first, insiders prioritize financial support and participate in plan execution and activities. Second, rural utilization and traditional agricultural succession activities and support are deficient. Third, administrators (intermediary) focuses primarily on KIAHS designation; ordinance enactment, manpower recruitment and other structural considerations are lacking. Fourth, the role of administrators (intermediary) is limited to operational funding and facility management support at the enforcement and activity stage. Fifth, outsiders besides visitors, such as the public or business enterprises, lacked participation methods. For the sustainable KIAHS, municipality must perceive agricultural heritage as a resource and recognize the importance, and treat it accordingly. The establishment of local-led conservation activities and movements must be considered in an enhanced investigation and excavation stage. The complementary policies that ensure continual support from experts from the first investigation and excavation stage to the final monitoring stage are necessary. The standards and regulations are necessary to achieve parity between conservation and maintenance of agricultural heritage, and its utilization.

• Journal of Korean Society of Water and Wastewater
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• v.34 no.6
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• pp.403-410
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• 2020

The difficulty of securing freshwater sources is increasing with global climate change. On the other hand, seawater is less affected by climate change and regarded as a stable water source. For utilizing seawater as freshwater, seawater desalination technologies should be employed to reduce the concentration of salts. However, current desalination technologies might accelerate climate change and create problems for the ecosystem. The desalination technologies consume higher energy than conventional water treatment technologies, increase carbon footprint with high electricity use, and discharge high salinity of concentrate to the ocean. Thus, it is critical to developing green desalination technologies for sustainable desalination in the era of climate change. The energy consumption of desalination can be lowered by minimizing pump irreversibility, reducing feed salinity, and harvesting osmotic energy. Also, the carbon footprint can be reduced by employing renewable energy sources to the desalination system. Furthermore, the volume of concentrate discharge can be minimized by recovering valuable minerals from high-salinity concentrate. The future green seawater desalination can be achieved by the advancement of desalination technologies, the employment of renewable energy, and the utilization of concentrate.

• Advances in concrete construction
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• v.13 no.4
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• pp.291-305
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• 2022

The present investigation deals with the production of the innovative lightweight fly ash angular aggregates (FAA) first time in India using local class 'F' fly ash, its characterization, and exploring the potential for its utilization as alternative coarse aggregates in structural concrete applications. Two types of aggregates are manufactured using two different kinds of binders. The manufacturing process involves mixing fly ash, binder, and water, followed by the briquetting process, sintering and crushing them into suitable size aggregates. Tests are conducted on fly ash angular aggregates to measure their physical properties such as crushing value, impact value, specific gravity, water absorption, bulk density, and percentage of voids. Study shows that the physical parameters are significantly enhanced as compared to commercially available fly ash pellets (FAP). The developed FAA are used in concrete vis-à-vis conventional granite aggregates and FAP to determine their compressive, split tensile and flexural strengths. Although being lightweight, the strength parameters for concrete containing FAA are well compared with conventional concrete. This might be due to the high pozzolanic reaction between fly ash angular aggregates and cement paste. Also, RCC beams are cast and the load-deflection behaviour and ultimate load carrying capacity signify that FAA can be suitably used for RCC construction. Hence, the utilization of fly ash as angular aggregates can reduce the dead load of the structure and at the same time serves as a solution for fly ash disposal and mineral depletion problem.