• Progress in Superconductivity
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• v.12 no.2
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• pp.75-81
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• 2011

We report on the progress that has been made in developing $MgB_2$ superconducting wires and tapes for commercialization and research efforts. A number of techniques have been developed to overcome the obstacle posed by the poor critical current density ($J_c$) of pristine $MgB_2$. Chemical doping has proved to be the effective way to modify and enhance the superconducting properties, such as the $J_c$ and the irreversibility field ($B_{irr}$). More than 100 different types of dopants have been investigated over the past 8 years. Among these, the most effective dopants have been identified to be SiC and malic acid ($C_4H_6O_5$). The best results, viz. a $B_{irr}$ of 22 T and $J_c$ of $30,000\;A{\cdot}cm^{-2}$ at 4.2 K and 10 T, were reported for malic acid doped $MgB_2$ wires, which matched the benchmark performance of commercial low temperature superconductor wires. In this work, we discuss the progress made in $MgB_2$ conductors over the past few years at the University of Wollongong, Hyper Tech Research, Inc., and Ohio State University.

• The Journal of Fisheries Business Administration
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• v.40 no.3
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• pp.189-205
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• 2009

This study is aimed to analyze the economic feasibility comparison of the extruded pellets and moist pellets on the Oliver flounder culture farms in Jeju Island. In order to do this, we selected 2 farms (M and S farms) in Jeju Island as a sample. In the study, various analyses including productivity analysis, cost structure analysis, profitability and economic feasibility analysis by feed type were conducted for two sample farms of Oliver flounder culture. The results of economic analysis by feed type on the Oliver flounder culture can be summarized as follows; First, there were not significant differences in productivity by feed type. Second, results of the profitability analysis on farm M by feed type showed the profitability was estimated to be 15.52% and 9.83% in EP and MP, respectively. In addition, the profitability of farm S was estimated to be 28.37% and 33.72% in EP and MP, respectively. Third, results of the economic analysis on farm M by feed type indicated that an internal rate of return(IRR) was 8% and 7% and a benefit-cost ratio was shown to be 1.64 and 1.11 in EP and MP, respectively. Furthermore, the economic analysis of farm M by feed type showed that an IRR was 19% and 24% and a benefit-cost ratio was calculated to be 1.4 and 1.51 in EP and MP, respectively. In summary, it is especially emphasized that economic valuation is not related to feed types (EP and MP). Finally, in order to improve the economic feasibility, it should be more focused on the efficient business management of the Oliver flounder aquaculture.

• Ocean and Polar Research
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• v.31 no.2
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• pp.167-176
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• 2009

Cobalt-rich manganese crusts on seamounts have received an increasing amount of attention as future resources for Co, Ni, Cu, and Mn. A dearth of detailed information regarding the relevant distribution characteristics, mining technologies, and ore processing technologies, however, has precluded potential evaluations of the technical and economic advantages of these crusts. In the past 4 years, Korea has undertaken a survey of the cobalt-rich manganese crusts in and around the Magellan Seamount and Mid-Pacific Mountains. This paper introduces the preliminary feasibility study of the distribution features and R&D results centered around the development of the cobalt-rich manganese crusts. The evaluation model was developed by modifying the model for the manganese nodules. In addition to considering the geological and geophysical differences between the manganese nodules and the cobalt-rich manganese crusts, an ore dressing subsystem was installed in the model. The mining subsystem is composed of a self-propelled collector--a pipeline with submersible hydraulic pumps for crust lifting. The smelting and chlorine leach method was selected for metallurgical processing. The production scales were established at 2,500t/y of cobalt metal. The production of three metals--cobalt, nickel, and copper--was considered in terms of metallurgical processing. The economic feasibility analyses demonstrated that the payback period was 11.4 years, the NPV was 36M$, and the IRR was 9.6% with the economic factors in the case of a cobalt price of US$ 25/lb. It was also demonstrated in this study that the payback period was 8.6 years, the NPV was 154M$, and the IRR was 14.0% in the case of a cobalt price of US$ 30/lb. This indicates that the approach under consideration appears to offer greater potential given the predicted metal prices.

• Journal of Sericultural and Entomological Science
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• v.10
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• pp.81-88
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• 1969

This study was carried out to investigate the effects of the cocoon cooking by infra red ray heater established in to the cocoon boiling machine. The results were summarized as follows. 1. According to the cocoons, the non bave end breaking percentage of cocoons was increased to 5∼9％ in spring and 2∼10％ in autumn. 2. There was no significant in the raw silk percentage. 3. The irradiation effect by the number of infra-red ray heater was different, namely, the raw silk percentage of the excellent cocoons was increased in case of 1 Kwatt irradiation, and that of the inferior cocoons was increased in the 2 Kwatt irradiation. 4. Reeling efficiency was showed to 14％ maximum and 3％ minimum(index).

• Korean Chemical Engineering Research
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• v.54 no.4
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• pp.501-509
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• 2016

The economic feasibility of a commercial indirect liquefaction process with the co-gasification process of petroleum coke which has been recognized as hazardous waste because of high sulfur content and bituminous coal and sub-bituminous coal mixtures was assessed. The 2,000 ton/day scale indirect liquefaction process including co-gasification, clean up, Fischer-Tropsch conversion and so on was assumed and used to analyze economical efficiencies with various conditions. Financial data from previous studies were modified and used and economical sensitivities with various mixture ratios were evaluated in this study. As a result, economic values of petroleum coke were superior than those of coals because of increasing sulfur sale. Also, mixtures with petroleum coke and bituminous coal was more favorable that those with petroleum coke and sub-bituminous coal due to lower moisture content. In case of sub-bituminous coal, the mixture ratio with petroleum coke had to be over 40wt% for the IRR of mixture to surpass 10%.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.69.2-69.2
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• 2011

The discovery of dark energy from Type Ia supernovae (SN Ia) is based on the implicit assumption that the look-back time evolution of SN Ia luminosity, after light-curve corrections, would be negligible. A strong support for this assumption was the apparent insensitivity of SN Ia distances across the host galaxy morphologies. However, Hicken et al. 2009 (H09) shows a systematic difference in the Hubble residual (HR) of $0.144{\pm}0.070$ mag between the E-S0 and Scd/Sd/Irr galaxies, after light-curve corrections. If true, this indicates that the light-curve fitters used by the SN Ia community can not correct for the population age (and therefore the evolution) effect. In order to confirm this, we have combined nearby SN Ia samples and the first-year SDSS-II SN Survey. The SNANA package was used for analyzing SN Ia light-curve, both for the MLCS2k2 and SALT2 fitters. We find a systematic difference in the HR of $0.10-0.13{\pm}0.030$ mag between E-S0 and Scd/Sd/Irr galaxies, which is in agreement with the result of H09, but now at the 3-5 ${\sigma}$ level. Considering the significant difference in the mean age of stellar population between these morphological types, the difference in the HR reported here suggests that the evolution effect of SN Ia luminosity should be considered in the cosmological application of SN Ia data.

• Plant Journal
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• v.9 no.1
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• pp.36-42
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• 2013

In this study, repowering scenarios are analyzed and evaluated from the economical point of view on a case by case basis. Based on the result of evaluation, the IRR indicates 2.34% on single 750 MW LNG combined cycle unit, 3.56% on 500 MW sub-bituminous PC units and 2.31% on 200 MW circulating fluidized bed combustion units, resulting in not reaching 7% rate of discount rate and being concluded uneconomical. However, proposes that it is most economical and feasible to repower power plant into 750 MW LNG combined cycle unit as long as the economic feasibility can be improved and it is necessary for old anthracite power plant to be repowered than rebuilt under the circumstances of lacking power supply.

• Korean Journal of Agricultural Science
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• v.25 no.2
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• pp.293-309
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• 1998

This study is aimed at identifying the decision making criteria as B/C ratio, IRR and NPV based on the expected benefits and costs of the land utilization and promotion projects which have implemented to improve agricultural structure under WTO system. To carry out the objectives of the study, Sinseok project area located at Dangjin district, Chungnam province was selected. Sinseok project area has 306.2 ha of paddy area with 172 farm households. The project area will be operated by the 33 specialized farm households after completion of the project which will have 20 years of economic life. After completion of the project, farm size will be increased from 1.8ha to 9.3ha. Land intensity of the project area will be increased by 10%. Increase of land productivity and cost saving due to the labor saving technology as farm mechanization will be expected. According to the survey results, the annual amount of production cost savings per farm was estimated 3.884million won and increased total farm income was expected about 43.8million won per year. The total expexted project benefits was expected 174million won per year. The project costs to promote land utilization and structural change consisted of handling charges, and direct payment for land movility. The decision making criteria representing economic feasibility of the project such as B/C ratio, NPV and IRR were estimated 2.49, 483million won and 30% respectively when the cut-off rate was taken into account 10%. In conclusion, the land utilization and promotion project proppeled by the Korean Government under the agricultural land law is considered economically feasible from the view points of expected project benefits and costs. Accordingly the project have to be implemented more strongly under the G't financial support considering WTO and UR negociation which were aimed at achieving the free trade and improvement of international competitiveness of farm products.

• Korean Journal of Agricultural Science
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• v.25 no.2
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• pp.310-320
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• 1998

This study is aimed at identifying the socio-economic effects of storage of ginger in artificial caves. The gingers stored in artificial caves in Seochun, 12 sampled areas, were surveyed to get information on the socio-economic effects. The surveyed data were processed by TSP, Qbasic and B/C Ratio computer programs and analyzed the decision making criteria such as B/C ratio, NPV and IRR. The socio-economic effects of the storages of the gingers are as follows. 1. The storage benefits per ton was showed as 184,050won. 2. Considering 10% of the opportunity cost of capital, the uper limits of investments for the cave storages was analyzed as 6,784 thousand won for ginger. 3. The investment of the natural cave storages was revealed economically feasible considering the decision making criteria as B/C ratio = 1.33, NPV = 35.059 thousand won and IRR = more than 100%. The other socio-economic effects of the ginger storages was expected as ; 1. The cave storages will contribute to increase consumer's and producer's welfare through the control of supply and demand and price stability. 2. Long-term storage of ginger without damaging quality and grades will be made on account of the storage conditions as relatively low temperature, high humidity and indifferent affects from the outside climate. 3. Utilization of the underground space, the caves, for storage will maximize the land use and the sustainable environment considering the mountainous area, two third of the total national land area. 4. Construction costs of the underground storage facilities as caves are cheaper than the ground storage facilities by 15 to 20% in general. In conclusion, the underground space like natural and artificial caves are considered the most suitable for storage of ginger on account of the storage conditions as temperature, humidity and blocking the sun light. Accordingly a study on convenient utilization of new development of artificial caves should be made considering transportation and input-output of the farms. Financial support of the government should be institutionally rearranged for the successful implementation of storing farm products like ginger in natural and man-made caves.

• Korean Journal of Agricultural Science
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• v.44 no.3
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• pp.451-461
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• 2017

Korean agriculture has recently focused on the 6th dimension of industrialization, which includes the functions of healing and care. The green care and healing business is one of the most representative models, satisfying modern consumers' needs for care or healing in rural agricultural environments. Many studies have shown physical and social benefits from green care and healing, but studies regarding economic performance are rarely found. The present study aimed to analyze the economic feasibility of different green care and healing farm complexes proposed in recent domestic research, with various possible combinations of business scenarios. The results show that most of the scenarios are economically feasible as B/C (benefit-cost ratio) and IRR (internal rate of return) are 1.19 and 8.53%, respectively, under scenario 1. This study also performed a break-even analysis for providing more flexible decision-making information. Overall, scenario 1 from green care and healing site and scenario 4 from green care and healing cluster are found to be superior to the other scenarios in terms of B/C and IRR. The scenarios in this study reflect the domestic farms or complexes which have similar functions of care or healing. Therefore, the results of this study provide information on practical policies and business implications in making decisions on the specific size and operational patterns when adopting green care and healing complexes by central or local governments and private sectors in the future.