• Journal of Preventive Medicine and Public Health
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• v.19 no.2 s.20
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• pp.281-292
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• 1986

Infection by hepatitis B virus is one of the major health problems of this nation. HBsAg positive rates of general population and school children were known to be as about 8 percent and 3.9 to 5.9 percent respectively. To study the incidence rate of hepatitis B infection in school children of rural area, author had examined 475 school children of relatively isolated agricultural area for baseline prevalence of hepatitis B virus serologic markers and followed up 415 school children during 10 months to determined the frequency of serologic conversion. The major results are summarized as followings: 1) Among the 278 susceptible children who were followed up, 26 had seroconversion for HBsAg or Anti-HBs. Therefore, the cumulative incidence rate during 10 months is estimated 9.4%. 2) The incidence rate of hepatitis B infection tends to increase with age (6-9yrs: 3.2%, 10-14yrs: 9.5%, 15-17yrs: 18.9%), and the incidence rate in male (13.0%) was higher than in female (5.7%). 3) The incidence rates of hepatitis B virus infection were not different statistically among three economic classes (The rates of lower, middle and higher class were 11.8%, 7.1% and 10.5%.). 4) The incidence rates of hepatitis B virus infection were not different statistically between visitors and non-visitors of clinic or hospital, dental clinic, persons received IV and not received IV, and persons with familial history and without familial history of liver diseases. Therefore all of these factors were not identified as risk factor of hepatitis B virus infection. And the transmissibility within the class of school was not recognized, too. 5) Among the 25 children who were HBsAg positive when enrolled, 15 (60%) were still HBsAg positive, who were identified as chronic carrier 15 of 415 school children were chronic carriers, then chronic carrier rate was estimated 3.6%, and there was no difference between sexes. 6) Of 38 children who had been Anti-HBs positive when enrolled, 5 (13.2%) lost Anti-HBs. Therefore, the loss rate of Anti-HBs per year is estimated to be 15.8%.

• Horticultural Science & Technology
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• v.19 no.2
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• pp.170-173
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• 2001

Postharvest diseases developed on harvested products result in a great economic loss. The objective of this research was to develop a chemical treatment to control major postharvest pathogens including Botrytis cinerea and Penicillium expansum in the cold storage room. Acetic acid ($2.4mg{\cdot}L^{-1}$, $4.8mg{\cdot}L^{-1}$) inhibits spore germination and mycelial growth of B. cinerea and P. expansum on PDA at room temperature ($25^{\circ}C$) and low temperature ($2^{\circ}C$). Fumigation of cold storage room with $SO_2$ ($5g{\cdot}m^{-3}$) gas or gaseous acetic acid ($4.8g{\cdot}m^{-3}$) prior to operation greatly reduced population of fungi in the cold storage room.

• Journal of agriculture & life science
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• v.46 no.5
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• pp.65-72
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• 2012

Salmonellosis is a widespread bacterial zoonosis that commonly causes enterocolitis and foodborne poisoning leading to an extensive economic loss in domestic animal industry. Considerably, the emergence of multidrug resistant strains of Salmonella spp. induces further severe problems affecting public health. The present report was designated to investigate the antibacterial efficacies of three common disinfectants including an oxidizing compound disinfectant (OXC), a triple salt (TS) and a quaternary ammonium compound (QAC) against Salmonella typhimurium subjected to the preliminary changes of drug temperature. All solutions of three disinfectants were pre-incubated at different temperature (22, 37 and $63^{\circ}C$) for 1 h prior to exposure to bacteria. The disinfectants and bacteria were diluted with distilled water (DW), hard water (HW) or organic matter suspension (OMS) according to treatment condition. Under the DW condition, the disinfectant efficacy of the QAC at $63^{\circ}C$ was higher than that of $22^{\circ}C$. Furthermore, under HW diluent the disinfectant efficacy of the TS pre-warmed at both of 37 and $63^{\circ}C$ were increased compared to that of $22^{\circ}C$. Considerably, the efficacy of pre-warmed QAC at both of 37 and $63^{\circ}C$ under the OMS diluent were higher than that of $22^{\circ}C$. Conclusively, prewarming at higher temperatures have positive effects on the stability of the antibacterial efficacies of TS and QAC.

• International Area Studies Review
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• v.12 no.2
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• pp.27-53
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• 2008

This paper investigates factors determining the level of nontraditional activities at banks around the world. Specifically, the paper examines what kinds of firm-specific and country-specific characteristics determine the level of noninterest income using a comprehensive multi-country database. This paper focuses beyond the traditional U.S. based analyses and provides detailed asset-liability management practices of banks around the world.The findings suggest that banks' size and loan loss provision, explicit deposit insurance, banking restriction, banking freedom ranking of respective countries, the extent of state and foreign ownership, governance, and transparency of the country have positive effects on the level of nontraditional activities. Greater dependence on traditional lending and financing, market based economy, and multiple bank supervisory bodies in the country have negative associations with noninterest income. The economic development of country however affects the extent of the relationship.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2012.05a
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• pp.586-591
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• 2012

The solution of maintenance decision support system for the gas turbine engine, which is currently operating in GUNSAN combined cycle power plant, was developed and is consist of online monitoring module, periodic performance trending module, optimal compressor washing interval analysis module and hot component management module. Also, GUI platform was applied to this solution for the user to monitoring the analyzed result of engine performance condition and then to make a decision of the consequent maintenance action. In online condition monitoring module, the performance degradation of engine is provided by the analysis of difference between the real time measurement data compared to exist engine performance. The optimal compressor washing interval module produced the washing interval of maximum net profit value by researching the maintenance expense and the loss profit value corresponds to the performance degradation with economic assessment algorithm. Thus, this solution support the user to enable the optimal maintenance and operation of gas turbine engine with overall analysis of engine condition and main information.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.21 no.5
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• pp.119-125
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• 2021

As the electricity grid systems has been intelligent with the development of ICT technology, power consumption information of users connected to the grid is available to acquired and analyzed for the power utilities. In this paper, the energy theft problem is solved by feature selection methods, which is emerging as the main cause of economic loss in smart grid. The data preprocessing steps of the proposed system consists of five steps. In the feature selection step, features are selected using analysis of variance and mutual information (MI) based method, which are filtering-based feature selection methods. According to the simulation results, the performance of support vector machine classifier is higher than the case of using all the input features of the input data for the case of the MI based feature selection method.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.5
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• pp.644-651
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• 2021

Viral hemorrhagic septicemia virus (VHSV) is a fish pathogen responsible for causing enormous economic loss to the aquaculture industry not only in Korea but worldwide. Thus, it is necessary to identify natural compounds that can be used to control the spread of VHSV. In this study, the anti-VHSV activities of five catechol derivatives, i.e., catechol, pyrogallol, 3-methyl catechol, veratrole, and 3-methyl veratrole-extracted from green tea-were assessed. The antiviral activities of these derivatives were found to be dependent on their structure, i.e., the hydroxyl or methoxyl group and their substituent groups-on the benzene ring. Catechol, pyrogallol, and 3-methyl catechol exhibited relatively high 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities than veratrole, and 3-methyl veratrole. Moreover, 3-methyl catechol harboring a methyl substituent group increased the viability of the virus-infected cells and resulted in a 2.86 log reduction in the gene copies of VHSV N (per mL) in real-time PCR analysis. In conclusion, the catechol derivatives harboring hydroxyl groups in their benzene ring exhibited higher antioxidant activities than those harboring the methoxyl groups. However, catechol derivatives with a methyl group at the 3'-position of the benzene ring exhibited higher antiviral activity than those harboring a hydroxyl group. To our knowledge, this is the first study to evaluate the relationship between the structure and the anti-VHSV activity of catechol derivatives.

• Journal of Microbiology and Biotechnology
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• v.31 no.8
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• pp.1088-1097
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• 2021

Grouper nervous necrosis virus (GNNV) infection causes mass grouper mortality, leading to substantial economic loss in Taiwan. Traditional methods of controlling GNNV infections involve the challenge of controlling disinfectant doses; low doses are ineffective, whereas high doses may cause environmental damage. Identifying potential methods to safely control GNNV infection to prevent viral outbreaks is essential. We engineered a virus-binding bacterium expressing a myxovirus resistance (Mx) protein on its surface for GNNV removal from phosphate-buffered saline (PBS), thus increasing the survival of grouper fin (GF-1) cells. We fused the grouper Mx protein (which recognizes and binds to the coat protein of GNNV) to the C-terminus of outer membrane lipoprotein A (lpp-Mx) and to the N-terminus of a bacterial autotransporter adhesin (Mx-AIDA); these constructs were expressed on the surfaces of Escherichia coli BL21 (BL21/lpp-Mx and BL21/Mx-AIDA). We examined bacterial surface expression capacity and GNNV binding activity through enzyme-linked immunosorbent assay; we also evaluated the GNNV removal efficacy of the bacteria and viral cytotoxicity after bacterial adsorption treatment. Although both constructs were successfully expressed, only BL21/lpp-Mx exhibited GNNV binding activity; BL21/lpp-Mx cells removed GNNV and protected GF-1 cells from GNNV infection more efficiently. Moreover, salinity affected the GNNV removal efficacy of BL21/lpp-Mx. Thus, our GNNV-binding bacterium is an efficient microparticle for removing GNNV from 10‰ brackish water and for preventing GNNV infection in groupers.

• The Journal of Fisheries Business Administration
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• v.52 no.1
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• pp.1-22
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• 2021

This study aims to face common threats from the depletion of fish resources, the decline of production and employment as well as the increase of life risk in East Sea Rim countries, North Korea, South Korea, Japan and Russia due to the Chinese fishing fleets entering East Sea. The recent competition in fishing among fishing vessels and fleets of national origin operating in the East Sea has induced a significant change in the ecological landscape of the fishing fleets cluster while having influenced production and employment in the fishing industries of South Korea and Japan as well as life threat on the fishermen in North Korea. It seems that the population organizational ecological theory can be applied to this change. It can be seen as the isomorphism of the selection process over the exclusive economic zone (EEZ) to avoid the environment in which these North Korean fishing vessels are pushed against the Chinese fleet in the North Korean part of the East Sea. To resolve the fishery disputes or conflict in the common waters in East Sea, first of all, Chinese fishing fleets will be required to put international pressure so as to solve the unfairness of the illegal fishing and overfishing by the International Fishery Organization or the UN violations of the sanctions against North Korea selling fishing rights to China. Although it is not easy for South Korea to cooperate with North Korea in the short term, South Korea will be able to support the fishery infrastructure in North Korea in the mid- to the long-term to prevent the loss of innocent lives for their fishermen and to raise their incomes.

• The Journal of Health Technology Assessment
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• v.6 no.2
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• pp.123-132
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• 2018

Objectives: Maternal morbidity and mortality are important healthcare issues. However there have been few studies on cost of illness (COI) from maternal disorders. This study aimed to estimate the COI due to maternal disorders in Korea. Methods: By reviewing previous studies and consulting expert we determined the scope of maternal disorders. We operationally defined maternal disorders as maternal hemorrhage, maternal sepsis, hypertensive disorders of pregnancy, obstructed labor, and abortion for maternal disorders. The reference period of this study is the year 2015. Main source of data were the National Health Insurance Service claims data, cause of death statistics from the Korea National Statistical Office, and the Korea Health Panel study. We classified the total costs into direct and indirect costs. The direct costs cover healthcare costs and non-healthcare costs. The indirect costs consist of productivity losses due to morbidity and premature death. Results: The cost of maternal disorders in 2015 was 229.7 billion won. The direct and indirect costs of maternal disorders were 165.2 billion won and 64.5 billion won respectively. The largest cost item for maternal disorders was healthcare cost (138.3 billion won, 60.2%). By age groups, the COI in 30-39 years old women were the highest (165.1 billion won, 71.9%). Abortion was the disorder with the highest COI among maternal disorders (71.9 billion won, 31.3%). Conclusion: The COI due to maternal disorders in Korea is quite substantial. Economic burden of maternal disorder increased when being compared with the year 2012 data despite the continued low birth rate in Korea. Therefore, it is necessary to continuously monitor the social costs of the maternal disorders in Korea.