• Korean journal of applied entomology
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• v.58 no.3
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• pp.203-207
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• 2019

Bemisia tabaci (Hemiptera: Aleyrodidae) is one of the major insect pests causing economic damages to over 900 different crops in the world. Especially, B. tabaci JpL (L. japonica) is known as a species living only in Japan and Korea so far, and mainly in Lonicera japonica and specific plant species. This study was conducted to investigate the occurrence and spread of B. tabaci JpL on Jeju Island in 2019. Of the total 25 areas surveyed, 1,003 individuals of B. tabaci JpL adults were collected from 24 L. japonica and one Conyza sumatrensis. All populations identified belonged to the JpL species. The result of this study showed that the population of B. tabaci JpL has increased at very high speeds to date compared to the previous reports in Korea.

• Journal of Veterinary Clinics
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• v.36 no.1
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• pp.15-22
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• 2019

Highly pathogenic avian influenza (HPAI) is among the top infectious disease priorities in Korea and the leading cause of economic loss in relevant poultry industry. An understanding of the spatial epidemiology of HPAI outbreak is essential in assessing and managing the risk of the infection. Though previous studies have reported the majority of outbreaks occurred clustered in what are preferred to as densely populated poultry regions, especially in southwest coast of Korea, little is known about the spatial distribution of risk areas vulnerable to HPAI occurrence based on geographic information system (GIS). The main aim of the present study was to develop a GIS-based risk index model for defining potential high-risk areas of HPAI outbreaks and to explore spatial distribution in relative risk index for each 252 Si-Gun-Gu (administrative unit) in Korea. The risk index was derived incorporating seven GIS database associated with risk factors of HPAI in a standardized five-score scale. Scale 1 and 5 for each database represent the lowest and the highest risk of HPAI respectively. Our model showed that Jeollabuk-do, Chungcheongnam-do, Jeollanam-do and Chungcheongbuk-do regions will have the highest relative risk from HPAI. Areas with risk index value over 4.0 were Naju, Jeongeup, Anseong, Cheonan, Kochang, Iksan, Kyeongju and Kimje, indicating that Korea is at risk of HPAI introduction. Management and control of HPAI becomes difficult once the virus are established in domestic poultry populations; therefore, early detection and development of nationwide monitoring system through targeted surveillance of high-risk spots are priorities for preventing the future outbreaks.

• Journal of Ginseng Research
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• v.43 no.1
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• pp.10-19
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• 2019

Background: Frequent overdose of paracetamol (APAP) has become the major cause of acute liver injury. The present study was designed to evaluate the potential protective effects of ginsenoside Rk1 on APAP-induced hepatotoxicity and investigate the underlying mechanisms for the first time. Methods: Mice were treated with Rk1 (10 mg/kg or 20 mg/kg) by oral gavage once per d for 7 d. On the 7th d, allmice treated with 250mg/kg APAP exhibited severeliverinjury after 24 h, and hepatotoxicitywas assessed. Results: Our results showed that pretreatment with Rk1 significantly decreased the levels of serum alanine aminotransferase, aspartate aminotransferase, tumor necrosis factor, and interleukin-$1{\beta}$ compared with the APAP group. Meanwhile, hepatic antioxidants, including superoxide dismutase and glutathione, were elevated compared with the APAP group. In contrast, a significant decrease in levels of the lipid peroxidation product malondialdehyde was observed in the ginsenoside Rk1-treated group compared with the APAP group. These effects were associated with a significant increase of cytochrome P450 E1 and 4-hydroxynonenal levels in liver tissues. Moreover, ginsenoside Rk1 supplementation suppressed activation of apoptotic pathways by increasing Bcl-2 and decreasing Bax protein expression levels, which was shown using western blotting analysis. Histopathological observation also revealed that ginsenoside Rk1 pretreatment significantly reversed APAP-induced necrosis and inflammatory infiltration in liver tissues. Biological indicators of nitrative stress, such as 3-nitrotyrosine, were also inhibited after pretreatment with Rk1 compared with the APAP group. Conclusion: The results clearly suggest that the underlying molecular mechanisms in the hepatoprotection of ginsenoside Rk1 in APAP-induced hepatotoxicity may be due to its antioxidation, antiapoptosis, anti-inflammation, and antinitrative effects.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.1
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• pp.138-146
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• 2019

LoRa LPWAN network system uses a license-exempt wireless communication system and implements data measurement through the integrated sensor based on Mems and wireless communication of existing measurement sensors. This system has superior technological / economic superiority using existing network and long distance communication compared to existing wireless measurement system, and secured economical efficiency by minimizing system construction equipment compared to wired measurement system. It is confirmed that the economical efficiency can be reduced by 41% compared to the conventional wired metering system. Since the LoRa LPWAN network system is excellent in terms of maintenance and operation, if installed in many bridges in Korea in the future, it will be developed as an excellent system in the maintenance of bridges. Etc.), and plant field (fire safety, etc.).

• Nuclear Engineering and Technology
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• v.51 no.2
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• pp.631-640
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• 2019

Thorium ($^{232}Th$) is four times more abundant than uranium in nature and has become a new important source of energy in the future. This is due to the ability of thorium to undergo the bombardment of neutron to produce uranium-233 ($^{233}U$). The aim of this study is to investigate the production cost of thorium oxide ($ThO_2$) resulted from the thorium extraction process. Four main parameters were studied which include raw material and chemical cost, total capital investment, direct cost and indirect cost. These parameters were justified to obtain the final production cost for the thorium extraction process. The result showed that the raw material costs were $63,126.00 - $104,120.77 (0.5 ton), $126,252.00 - $178,241.53 (1.0 ton), and $1,262,520.00 - $1,782,415.33 (10.0 tons). The total installed equipment and total cost investment were estimated to be approximately $11,542,984.10 and $13,274,431.715 respectively. Hence, the total costs for producing 1 kg $ThO_2$ were $6829.79 - $6911.78, $3540.95 - $3592.94, and $501.18 - $553.17 for 0.5, 1.0, and 10.0 tons respectively. The result concluded that with higher mass production, the cost of 1 kg $ThO_2$ would be reduced which in this scenario, the lowest production cost was $$501.18kg^{-1}$-$$553.17kg^{-1}$ for 10.0 tons of $ThO_2$ production.

• Journal of the Korean Society for Environmental Technology
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• v.19 no.6
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• pp.514-527
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• 2018

This study formed a scenario to improve a water quality by expecting and analyzing a water quality of Jeollabuk-do Seomjingang water system, so calculated a result. As a result, it was analyzed that a water quality is improved at 15.32 % of the maximum BOD, 7.17 % of T-N, and 62.86 % of T-P according to domestic and livestock cut amount by reinforcing discharge water of sewage disposal plant and improving pollutant management plans. It was analyzed that supplementing various cut plans such as establishment of efficient cut plans, plans to decrease pollution loading amount, plans to increase sewage disposal efficiently, pollutant decrease through an expansion of sewage disposal area, and energy recovery from animal dung of Total Pollutant Load Management System, and developing a study on more efficient improvement plans of water quality by considering natural increase and economic development are efficient in an improvement in a water quality.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.10
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• pp.1302-1309
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• 2021

Recently, the Korean Government announced the Korean New Deal as a national development strategy to overcome the economic recession from the pandemic crisis and lead the global action against structural changes. In the Korean New Deal, the Green New Deal related with the energy aims to achieve net-zero emissions and accelerates the transition towards a low-carbon and green economy. To this end, the government plans to promote an increased use of renewable energy in the society at large. This paper introduces a binary power generation using unused low-grade thermal energy to accelerate the transition towards a low-carbon and green economy and examines a control system based on Neural Network which is capable maintenance at low-cost by an unmanned automated operation in actual power generation environment. It is expected that the realization of binary power generation accelerates introduction of renewable energy along with solar and wind power.

• Journal of Digital Convergence
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• v.17 no.11
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• pp.501-508
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• 2019

Today, home gardening is in the spotlight. Therefore, the necessity of developing a new type of gardening product was raised according to the consumer's desires. This study, the contents were developed using sparrows, a helper who helped the bean rat's grain-cracking task among the characters of 'kongjwi patjwi'. The cultural contents convergence product is a lid production that is used at the end of the plant support. The fabrication method was designed using UG NX program after design research, and after printing by 3D polyjet method, mold was made and cast into silicon and resin. Through product manufacturing, we could confirm the public's interest in the possibility of new products and creativity. In the future, it is expected that the development of products incorporating cultural contents through various cultural archetypes will be activated, contributing to the enhancement of economic added value and national brand value.

• Journal of Korean Society on Water Environment
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• v.27 no.3
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• pp.349-356
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• 2011

This study, which evaluated the contribution of the real economic value and system in the Nakdong River Basin, estimated the emergy analysis for environmental accounting of the TMDL program. And an environmental accounting for TMDL is evaluated before and after adopting TMDL program respectively. The value of emergy after adopting the TMDL was 7.90 E+20 sej/yr. Although the real yield of the river after governmental investment was high (before: 9.7118 E+20 sej/yr and after: 9.7224 E+20 sej/yr), the effects of improvement was not great, in terms of an investment cost. The benefit/cost ratio resulted from environmental accounting has decreased from 1.493 to 1.230 due to the cost of managing treatment facilities. The method of improving water quality in the Nakdong River Basin by the TMDL program should be changed into an ecological treatment facilities using resources efficiently from a control of water quality depending on expansion of the wastewater treatment facilities and advanced treatment plant using high cost and non-renewable energies.

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.585-590
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• 2011

The purpose of this research is to suggest economic feasibility of cultivating Acer Mono by using profitability analysis to forest owners. To achieve this research objective, forest owner household survey with intensive cultivating has been conducted about a sap production on its age of tree. And input costs and sap production costs are calculated with silvicultural system from plant to regeneration cutting. Total income is the sum of its sap sales and thinning and regeneration cutting. The method of profitability analysis was used on the NPV(Net Present Value) and IRR(internal rate of return). Finally, when 3% discount rate is applied, NPV is about 59,436 thousand won and IRR value is 9.22% at this point. This result, therefore, proves that cultivating Acer Mono is economical feasibility to forest owners.