• International Journal of Railway
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• v.1 no.2
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• pp.37-44
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• 2008

Safe, fast, efficient and effective railway is a main factor of economic development level of every country. This paper uses the DEA method to evaluate and compare the efficiency of 12 Regions of RAI. In addition, we introduce the reference(s) unit(s) for every inefficient region, and determine the amount of input decrease and/or output increase need to become them efficient. Findings indicate that in 2006, 4 regions of 12 are in Constant Return to Scale (CRS) status and 7 of them in Variable Return to Scale (VRS), and the average efficiency is 0.730 and 0.888, respectively. In other words, RAI works 27 percent under its capacity. More over results indicate that Hormozgan, Khorasan, Tehran and Isfahan Regions have the most efficiency respectively. The results show that the 8 regions, have been working in Increaser Return to Scale and 4 reminder Regions in Decrease Return to Scale. According to this results, we submit the suitable suggestion for improve the efficiency of the inefficient regions.

• Proceedings of the KSRS Conference
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• v.1
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• pp.360-363
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• 2006

The red tide related with Cochlodinium Polykrikoides bloom has been frequently occurred around the South Sea of Korea and caused the economic loss in the coastal breeding grounds. The outbreak scale was usually change by physical, biological and environmental condition at each years. Relatively large-scale red tide occurred in 1995, 1997, 1999, 2001, 2002 and 2003 through spatial scale, duration and maximum density. Compared the scale of red tide with physical condition around the South Sea, the lower coastal temperature on August around the South Sea corresponded with the large scale red tide. By serial oceanographic investigations on August in the South Sea and estimated wide area temperature information by satellite, SSTA around the South Sea and wide area was negative when the outbreak of red tide was large scale. From the results of temperature difference between surface and 30m layers, the occurrence of enormous red tide has a tendency when the temperature gradient around the seasonal thermocline was weakened. Larger Kuroshio volume transport in the upstream was also corresponded with the large scale red tide.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.9
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• pp.1326-1330
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• 2001

This study analyzed the lowest production cost and the greatest profit to be obtained from marketing hogs to determine the optimal operation scale for family-owned farrow-to-finish farms. Data were collected from 39 farrow-to-finish farms with 500 to 5,000 inventories for two consecutive years, and treated with GLM and quadratic regression models using the REG procedure. Analysis results indicated that farms capable of marketing 2,933 and 3,286 hogs annually had the lowest production cost and the greatest profit, respectively. Further analysis attributed the lowest production cost or the highest return in farms with an optimal scale of 3,000 to a higher survival rate of the herd, as well as lower expenses in veterinary medicine, labor, utilities and fuel, transportation, and depreciation. A similar feed conversion efficiency was observed for all the farms studied. Obviously, the cost efficiencies were associated with the economy of the operation scale of hog production until it reached 3,000 hogs marketed annually for a family-run unit. Beyond the optimal scale of 3,000 hogs, good stockmanship was more difficult to maintain and the herd management deteriorated as increasing mortality confirms. It is conclude that, unless advanced management is applied, the operation scale should not expand beyond 3,000 hogs.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.09a
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• pp.303-310
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• 2003

Small-scale models have been frequently used for experimental evaluation of seismic performance because of limited testing facilities and economic reasons. However, there are not enough studies on similitude law for analogizing prototype structures accurately with small-scale models, although conventional similitude law based on geometry is not well consistent in the inelastic seismic behavior. When fabricating prototype and small-scale model of reinforced concrete structures by using the same material, added mass is demanded from a volumetric change and scale factor could be limited due to size of aggregate. Therefore, it is desirable that different material is used for small-scale models. Thus, a modified similitude law could be derived depending on geometric scale factor and equivalent modulus ratio. In this study, compressive strength tests are conducted to analyze equivalent modulus ratio of micro-concrete to normal-concrete. Equivalent modulus ratios are divided into elastic, weak nonlinear and strong nonlinear phases, which are based on ultimate strain level. Therefore, an algorithm adaptable to the pseudodynamic test, considering equivalent three phase similitude law based on seismic damage levels, is developed. In addition, prior to tile experiment, it is verified numerically if tile algorithm is applicable to the pseudodynamic test.

• Journal of Energy Engineering
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• v.18 no.3
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• pp.175-190
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• 2009

This study examines the influence of scale economy, technology, financing capability and market competition on economic performance by value chain in Korean solar energy companies, using the multiple logistic regression analysis. The current profit ratio is analyzed to have been positively affected by financing capability, while negatively by market competition. The scale economy and technology are analyzed to have no statistical significance on the economic performance. The current profit ratio for companies creating higher value in the sourcing process is negatively affected by technology while positively by financial capability. The one in the manufacturing process is affected positively by technology and financing capability, and the one in the marketing process is affected positively by financing capability while negatively by market competition. The implications of this study are as follows: Korean solar energy industry is recommended i) to establish the specific innovation system for technology development, ii) to set up advanced financial system, iii) to carry out the fractal system, the manufacturing system through the network of the firms owning core competence per value chain.

• Transactions of the Korean hydrogen and new energy society
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• v.25 no.2
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• pp.173-182
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• 2014

Dimethyl ether (DME) is a new clean fuel as an environmentally-being energy resources. DME has similar characteristics to those of LPG and can be substituted Diesel fuel. KOGAS has investigated and developed new innovative DME synthesis process from synthesis gas with KOGAS's own technologies. KOGAS had finished the construction of 10ton/day DME demonstration plant in 2008, we have established the basic design of commercial plant which can produce 3,000ton/day DME. Specifically, an economic model for a commercial DME project will be presented. It accounts for all the major cost factors that are considered in a commercial scale project as the model input for performing cash flow analysis, after which key economic indicators are produced including the internal rate of return (IRR), net present value (NPV). Sensitivity analysis is performed to identify dominant cost factors to the project economics and quantify their impact. The inputs to the economic analysis will be based on representative cost factors from the commercial-scale design of KOGAS' direct DME process supplemented by literature data. Case study results will be presented based on recent commercialization projects.

• The Korean Journal of Community Living Science
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• v.28 no.4
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• pp.653-667
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• 2017

The purpose of this study were to investigate the socio-economic impacts of urban-to-rural migration on the rural community and to identify the factors influencing rural residents' recognition of the socio-economic impacts of urban-to-rural migration on the rural community. For the purpose, this study analyzed Korea Rural Economic Institute's rural residents survey(2016), using multiple regression model. The main finding of this study were as follows: Positive social impacts of urban-to-rural migration on rural community were (1) contributing to community sustainability through population growth, (2) contributing to securing agricultural human resources, and others. Negative social impacts of urban-to-rural migration on rural community were (1) increasing unnecessary complaints and deepening distrust, (2) weakening of community consciousness, and others. Positive economic impacts of urban-to-rural migration on rural community were (1) increasing the value of residents' property, (2) contributing to local finance through increased local tax revenue, and others. Negative economic impacts of urban-to-rural migration on rural community were (1) difficulty of scaling farmland due to small-scale farming, (2) land shortage caused by rising land prices, and (3) fierce competition to secure labor force. According to the multiple regression analysis, the major factors influencing rural residents' recognition of the socio-economic impacts of urban-to-rural migration were (1) villagers' general attitude toward urban-to-rural migrants, (2) urban-to-rural migrants' community participation, (3) age, and (4) fitness of village in urban-to-rural migration.

• Journal of Agricultural Extension & Community Development
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• v.9 no.1
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• pp.29-41
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• 2002

The purpose of this study was to explore socio-economic effects of participation in weekend farming. This study was carried out through review of literature and descriptive survey. The data for the study were gathered from 135 randomly sampled urban people who participated in the weekend farming activity. Small scale weekend farming activity of the urban people led them to better quality of life in terms of educational and socio-economic conditions. The major findings of the study were as follows; 1) Weekend farming supplied fresh vegetables to participating urban households, however, showed relatively low economic effects. 2) Participating urban people have experienced new relationships with other participants and could better understood their family members of weekend farming activity. 3) Participating urban people responded that they could improve their quality of life through weekend farming activity. 4) Weekend farming activity proved to be a useful educational experience for children and youth.

• The Journal of Asian Finance, Economics and Business
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• v.5 no.3
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• pp.157-167
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• 2018

This research aims to generalize the conceptual basis of precariousness of employment, study the factors and scale of unsustainable of employment in the countries of the Eurasian Economic Union (EAEU). The concept of precariousness of employment is formed in social and economic studies about 40 years ago, but objective and subjective conditions and forms of unsustainable employment existed before. This study proposes a classification of forms of precariousness of employment on 16 criteria: the duration and timing of agreements, contract terms, the nature of income; the degree of labor autonomy; the level of formality; the level of openness; the level of vulnerability; the conditions of growth of qualification; the level of flexibility; the level of stability; regularity; the severity of the danger of work; in relation to the workplace; the quality of employment, the level of social security. In this research highlighted factors (globalization, demography, migration, structure factors, shadow and informal economy, social development and living standards, unemployment), and systematized certain trends of precariousness of employment, channels and means, forms of manifestation. The empirical analysis identified of the labor potential of the Eurasian countries and new quantitative estimates of the levels of unsustainable employment in the Eurasian Economic Space.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.4
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• pp.559-567
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• 2011

This paper deals with an economic evaluation of domestic low-temperature water electrolysis hydrogen production. We evaluate the economic feasibility of on-site hydrogen fueling stations with the hydrogen production capacity of 30 $Nm^3/hr$ by the alkaline and the polymer electrolyte membrane water electrolysis. The hydrogen production prices of the alkaline water electrolysis, the polymer electrolyte membrane water electrolysis, and the steam methane reforming hydrogen fueling stations with the hydrogen production capacity of 30 $Nm^3/hr$ were estimated as 18,403 $won/kgH_2$, 22,945 $won/kgH_2$, 21,412 $won/kgH_2$, respectively. Domestic alkaline water electrolysis hydrogen production is evaluated as economical for small on-site hydrogen fueling stations, and we need to further study the economic evaluation of low-temperature water electrolysis hydrogen production for medium and large scale on-site hydrogen fueling stations.