• KIPS Transactions on Computer and Communication Systems
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• v.9 no.4
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• pp.83-88
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• 2020

In Solar-powered wireless sensor networks(SP-WSN), the battery is periodically charged, so the best use of harvested energy is more important, rather than minimizing energy consumption. Meanwhile, as is well known, the reliability of communication between sensor nodes is very limited due to the resource-constraint of sensor nodes. In this paper, we propose an advanced FEC (forward error correction) scheme which can give SP-WSN more reliability for communication. Firstly, the proposed scheme uses energy modeling to calculate the amount of surplus energy which can be utilized for extra operations, and then determines the number of additional parity bits according to this amount of surplus energy. At the same time, link quality modeling calculates the optimal parity bits for error recovery in the current data communication environment. Finally, by considering these two parity sizes, it is possible to determine the optimal parity size that can maximize the data reliability without affecting the node black out. Performance verification was performed by comparing the amount of data collected at the sink and the number of outage nodes with other schemes.

• The Journal of Fisheries Business Administration
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• v.22 no.2
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• pp.53-74
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• 1991

Interest on ocean environment has increased with the development of industrialized activities. Public marine resorces are defined broadly to include fish stocks, beaches, marine waters, recreational fishing, biota, waterfowls, shorebirds, seabirds and marine mammals But, it is not easy to analyze compensation for injury to publicly owned marine resources because the claimants do not exist clearly and the economic methodology of damage on public goods is not developed fully. This paper introduces basic idea of welfare economic theory and environmental legislation to the research question : How the economics and law can be applied to the case of damage on publicly owned marine resource. The paper discusses the concepts of willingness to pay (WTP) and willingness to accept (WTA). It is accepted generally that WTA is correct concept of welfare change in the case of damaged public goods. Four methods (compensating variation, equivalent variation, compensating surplus, equivalent surplus of measuring welfare changes are compared. Compensating variation(CV) is the best measure of welfare changes are compared. Compensating variation(CV) is the best measure of welfare changes caused by environmental damage. Vartia (1983) showed CV could be measured from the ordinary demand function using the differential equations. This paper also provides an overview of the emerging U.S. and Korea legal system for compensation for natural resource damages, with particular emphasis on U.S. legal system under Comprehensive Environmen-tal Response Compensation and Liability Act (CERCLA). These regulations are to include two different types of standardized procedures for assessing natural resources injury : Type A or simplified assessment techniques for small releases ; and Type B protocols that would include detailed and extensive assessment methodologies for major releases. Type A procedures are specified by Natural Resources Damage Assessment Model for Coastal and Marine Environment (NRDAM/CME) of the U.S. CERCLA provides a legal 'legitimization for the use of economic-based nonmarket valuation in the courts and have introduced appropriate and accurate nonmarket valuation methods based on willingness to-pay for damage assessment. By briefly reviewing economic theory and environmental legislation, we hope to help provide a better understanding of the compensation process and the economics of publicly owned marine resources in the U.S. and to integrate the economics and law of natural resources valuation into a single comprehensive package in Korea.

• Journal of Families and Better Life
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• v.22 no.2
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• pp.97-107
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• 2004

The purposes of this study were compare the leisure attitudes, leisure activities, and leisure constraint among three different generations - teenagers, adults, and elderly adults. Data were obtained from a Questionnaire completed by both male and female lived metropolitan, and aged over 13. Using the factor analysis, this study classified the types of leisure attitudes. The leisure attitude was divided to 4 factors - reducing stress, self-realization, family activity, and surplus time. In order to compare the attitudes, activities, and constraints of leisure among three different generations, ANOVA was used The findings of this study are as follows: First, there were significant differences between teenager group and the others. The teenagers (n=107) recognized the leisure as a mechanism of reducing stress, or as just surplus time. They liked sports, computer games, travels, and reading books, but were not likely to like leisure activities shared with family members. Their leisure constraints were significantly larger than those of the other groups. Teenagers' constraints of time, money, and skills could be leisure barriers. Second, adults group (n=123) attached importance to the family leisure activities. They liked to spend time with their family members, but they seemed to be relatively passive in most types of leisure activities. They like to read newspapers and magazines, and to participate in religious activities. Third, elderly adults' (n=86) purpose of leisure activities was to improve the health condition, and to develop relationships with their friends. They liked sports such as swimming and aerobic dance, travels, religious activities and community service activities. Their good health condition and economic resources could decrease the leisure constraints.

• Journal of Embryo Transfer
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• v.16 no.3
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• pp.245-250
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• 2001

This study was performed to evaluate whether vitrification method using ethyle glycol and eletron microscopic (EM) grid could be used far the cryopreservation of human oocytes in ART program. Surplus oocytes were obtained from consented IVF patients. These surplus human oocytes were frozen with our vitrification method, Oocytes were exposed to 1.5M ethylene glycol (EG) in DPBS far 2,5 minutes, followed by 5.5M EG plus 1.0M Sucrose in DPBS for 20 seconds. Then oocytes were transferred onto the EM grid and the grid was plunged into LN2 for storage. For thawing, oocytes containing EM grid were sequentially transferred in 1.0M, 0.5M, 0.25M, 0.125M and 0 M sucrose in DPBS solution at the intervals of 2.5 minutes. Thawed and survived oocytes were provided for ICSI. Embryos from vitrified oocytes were transferred to uterus of the patient on 4 to 5 days after ovulation in natural cycles of on 15 to 17 day of hormone replacement cycles. A total of 370 oocytes from 26 patients were thawed and 159 (43.0%) of them survived. One hundred thirty four oocytes (84.3%) were fertilized normally and 126 pre-embryos were transferred to 26 patients, resulting in 5 clinical pregnancies. The pregnancy rate per transfer was 19.2% and implantation rate was 4.0%. Among the five pregnant, 4 patients delivered 4 healthy babies and the one patient was 32-week ongoing pregnancy. From this results, vitrification using ethylene glycol as cryoprotectant and EM grid is a rapid and simple method that can be effectively applied for the cryopreservation of human oocytes in ART program.

• Fashion & Textile Research Journal
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• v.13 no.2
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• pp.269-278
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• 2011

This study aims at setting up productive capacity which can be usefully utilized for work management of apparel manufacturers. So as to achieve this goal, an apparel manufacturing company which has been operated by miniline system in Seoul was selected. Standard time and man-hour were calculated to create the accurate productive capacity by observing and measuring a work flow included cutting, sewing and finishing processes. And the result is as following. The standard time for each process was presented as cutting process 47004.5s, sewing process 671050.5s and finishing process 22426.3s. And 15284.4ms was computed as total procession man-hour per day of the manufacturer which is organized of 16 people. Also, the procession man-hour for each process was revealed as cutting process 396.7ms(2.6%), sewing process 14509.3ms(94.9%) and finishing process 378.5ms(2.5%). +Surplus was found in the productivity for each process included the cutting process(outshell, lining and seam process), the sewing process(preparation and arrangement process) and the finishing process. But, additional man-hour 52436.18ms was required because the productive capacity was calculated as -surplus(-13.9%) in the sewing process(part and assembly process). Therefore, a work schedule was planned based on the previous result. However, loading can be ideal when a capacity and a load become '0'. The object company should find the way to reduce allowance(26.25%) of the sewing process through reconstruction of consciousness and improvement in functions with analyzing works of operators. Also, they need to consider an additional supplement of the personnel.

• Proceedings of the Safety Management and Science Conference
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• 2005.11a
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• pp.569-579
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• 2005

International capital movement has made progress at global liberalization of finance and foreign exchange, international monetary norm changing into floating exchange rate system, easiness of collection of information and trade at improvement of information communication technology from early of 1970's. Results of empirical test for relation between foreign exchange rate or various determination factors of foreign exchange rate and interest rate are followed by next sentences. First, according to relation between foreign exchange rate and interest rate, correlation for each of variables after OECD entrance is increased. 'But, long-term & short-term interest rate is affected by Hanbo & Kia's bankruptcy, continuous large scale coporates bankruptcy and crisis of foreign exchange. Therefore, financial instability is occured. If portfolio investment fund has been inflow as it is mollified by continuous shortage of foreign exchange and fall of country's credit rating, it is expected to have positive effect for long-term & short-term interest rate from appreciation of won against dollar. Second, results from relation between determination factor of foreign exchange rate and interest rate are followed by next sentences. If surplus of current account and goods account is continued, yield of corporate bond is to be stable. But, margin of surplus is expected to diminish after second quarter 98, and difference between external and domestic interest (after adjusting foreign exchange rate) is to be diminished. And if net inflows of foreign investor's fund (stock and bond) is diminished, it is to have negative effect for yield of corporate bond. According to foreign investor's investment movement of previous years, hedge fund were stayed at least during two years in Mexico. It means that sudden capital outflow is not to be happened at Korea.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.6 no.4
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• pp.173-194
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• 2011

This paper analyzes quantitative economic effect of accuracy improvement in location based services. This analysis is motivated from the situation that Korea Communications Commission is preparing the notification for 'location accuracy standard.' The analysis includes three level of impacts. Firm level analyzes the impact on revenue of firms. Social level additionally includes consumers' surplus in LBS industry. Lastly, economywide level includes ripple effects to another industries, which uses input-output analysis. The result of analysis shows that the economic value reaches to considerable amount and cost-benefit ratio is considerably high. The consumers' surplus is much larger than revenue increase. This result supports the intuition that many of location based services are for public interest and that the services have much externalities among firms and consumers. This means that the role of government is very important in the execution of accuracy improvement.

• Journal of Microbiology and Biotechnology
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• v.9 no.2
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• pp.140-146
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• 1999

When methanol was the sole carbon source, Methylobacterium organophilum NCIB 11278, a facultative methylotroph, accumulated Poly-$\beta$-hydroxybutyrate (PHB) as 59% (w/w) of dry cell weight under potassium limitation, 37% under sulfate limitation, and 33% under nitrogen limitation. Based on a stoichiometric analysis of PHB synthesis from methanol, it was suspected that PHB synthesis is accompanied by the overproduction of energy, either 6-10 ATP and 1 $FADH_2$ or 6 ATP and 3 NADPH to balance the NADH requirement, per PHB monomer. This was confirmed by observation of increased intracellular ATP levels during PHB accumulation. The intracellular ATP with limited potassium, sulfate, and ammonium increased to 0.185, 0.452, and 0.390 $\mu$moles ATP/g Xr (residual cell mass) during PHB accumulation, respectively. The intracellular ATP level under potassium limitation was similar to that when there was no nutrient limitation and no PHB accumulation, 0.152- 0.186 $\mu$moles ATP/g Xr. We propose that the maximum PHB accumulation observed when potassium was limited is a result of the energy balance during PHB accumulation. Microorganisms have high energy requirements under potassium limitation. Enhanced PHB accumulation, in ammonium and sulfate limited conditions with the addition of 2,4-dinitrophenol, which dissipates surplus energy, proves this assumption. With the addition of 1 mM of 2,4-dinitrophenol, the PHB content increased from 32.4% to 58.5% of dry cell weight when nitrogen limited and from 15.1 % to 31.0% of dry cell weight when sulfate limited.

• Journal of Digital Convergence
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• v.15 no.10
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• pp.113-121
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• 2017

Korea is a country that needs trade. Because it lacks natural resources but has excellent skills and manpower. Trade balance means 'profit from the process of buying and selling various goods and services in many abroad countries'. If the export amount of Korea is more than the import amount, it is called the trade surplus. The purpose of this study is to find trends and future directions of exports and imports over the last 210 months for the US, China, Japan, United Kingdom which have large trade with Korea, Since 2000, China's exports have grown more than 800%. However, in the case of the US and Japan, there is a steady increase rate of around 200% without any major change. In order for Korea to increase exports for the surplus of trade balance, it seems that the increase in exports to the US and Japan as well as the increase in exports to China are more important. Since the rate of growth has been declining slightly due to the decline in exports of auto makers to China since 2014, we need a strategy to prepare for this.

• The Journal of Society for e-Business Studies
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• v.5 no.1
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• pp.135-158
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• 2000

In recent years, many retail businesses jumped on the Internet auction bandwagon and paid substantially high fees to learn and develop proper business strategies for this new environment. Unlike what most businesses in the real world presume, this research shows that discriminatory-price ascending-bid auctions in a digital economy might be not very beneficial for the sellers on the Internet, if sellers sell the identical digital products through both a typical posted-price market and an auction. Using an extensive technology infrastructure along with suitable incentives and rules for market agents, we found that a discriminatory-price ascending-bid auction, which is the most popular auction mechanism on the Internet, serves consumers better than it does the sellers or producers in the digital economy. That is, the average prices for digital goods in these auctions are substantially lower than the prices in a posted-price market. This shows that it is not so wise for sellers to jump on the bandwagon of Internet auctions, if there is a market place with posted-price mechanisms which sells comparable items, or if a seller does not have special advantages or strategies in this new market institution. Electronic market mechanisms provide powerful means of understanding and measuring consumer characteristics including willingness-to-pay and other demographics for sellers or producers. Many concern that sellers may extract the entire surplus from the market by using customization on the Internet, thus consumers will be worse off in this digital economy. We found that these sellers who can customize their products and prices fail to capture the whole consumers surplus and cannot exercise a monopoly. One major explanation for this phenomenon is that the competition among the sellers prohibits them from charging prices according to customers demand for each product, where switching from one seller to another is not so difficult for the customers, and reselling products among the buyers are prohibited.