• Research in Plant Disease
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• v.12 no.3
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• pp.231-234
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• 2006

The influences of powdery mildew caused by Sphaerotheca fusca were assessed on cucumber to verify the economic injury level and yield response. Based on the relation of disease severity and yield response, economic threshold was determined by grading the disease severity of powdery mildew. Yield loss simulation due to damage of powdery mildew was conducted by defoliation of lower cucumber leaves in two seasons. The minimum number of leaves was 10 in spring season and 13 in autumn season which made no distinct difference on cucumber yield. The whole yields of cucumber was reduced as the disease severity was increased. Therefore occurrence of powdery mildew have a negative effect on cucumber yield. The regression equation between disease severity and yield loss showed Y=-57.237x+6143.1, $R^2=0.9628$. This equation suggests the disease severity of economic threshold is 17.6%, which is 3% reduction point of yield based on yield and economic relations. These results suggest that application of fungicide should be needed when 1 or 2 leaves of cucumber are infected by powdery mildew in the growing season.

• The Korean Journal of Pesticide Science
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• v.18 no.3
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• pp.175-180
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• 2014

This study was carried out to determine the economic injury level and economic threshold level on beet (Beta vulgaris L.) infested with Spoladea recurvalis in the plastic greenhouse condition in 2010. The second instar larvae of S. recurvalis were inoculated with 7 different density levels on the each 10 beet plants as a replication. Injury levels of beet leaves and density of S. recurvalis were increased with the inoculation density of S. recurvalis. However, yield and marketable commodity of beet were decreased. Linear relationship between the percent yield reduction (Y) of beet leaves and different infestation densities of S. recurvalis (X) was estimated by the following equation Y = 1.226x + 3.36. Based on the relationships between the densities of S. recurvalis larvae and yield index of beet leaves, the number of second instar larvae which caused 5% loss of yield, economic threshold level was estimated as 1.1 larvae/10 plants for the planting 10 days. The percent yield reduction (Y) of beet roots infested with different densities of S. recurvalis (X) estimated by the following equation Y = 1.537x + 1.4634 after inoculation for 10 days at 3rd harvesting of leaves. Based on the relationships between the densities of S. recurvalis larvae and yield index of beet roots, the number of second instar larvae which caused 5% loss of yield, economic threshold level was estimated as 6.4 larvae/10 plants for the planting 10 days.

• Proceedings of the KIEE Conference
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• 2002.07b
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• pp.1316-1318
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• 2002

A methodology for reliability and economic analysis of wind embedded electric power system is presented in this paper. This is done by evaluating the reliability index, loss of load expectation (LOLE), for the power system with and without integration of wind system in the overall electric power system. Economic analysis of the wind energy embedded electric system is done in terms of conventional fuel saving assessment due to the use of wind power generation units.

• Journal of the military operations research society of Korea
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• v.28 no.1
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• pp.136-149
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• 2002

The UAV(Unmanned Aerial Vehicle) offers numerous benefits to the military. The benefits it can provide are to perform an operation without loss of life and economic life cycle cost. This clearly showed us the benefits of using UAVs in the operation, especially in politically hostile and sensitive areas. While the American military first used UAVs, it is Israel that has used them best in real situations. In this paper, it is summarized the types and the OPCONs (Operational Concept) of UAVs and the values. Looking at the technology trends, and it is showed the benefits of UAV in the economic side feasibility, to emphasis on the future values of the UAVs as a newly emerging weapon systems.

• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.36-38
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• 1993

This study considers the economic aspect of the distribution automation system, which is the decision-making criteria of the electric utilities for the investment. The feeder automation candidate region is divided into two types of the urban and the rural. The total investment cost of the feeder automation for each type is estimated. The annual cost, is also estimated, by finding the fixed charge rate. To compare the annual cost and the economic effect cost, for the investment decision-making, the costs are quantitatively estimated on the following effects : the manpower replacement, the outage cost saving, the main transformer utilization improvement, the feeder utilization improvement, and the line loss reduction.

• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.192-194
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• 1993

This paper presents an efficient method for determining the economic dispatch of thermal generator using an alternative Jacobian matrix considering system constraints. The transmission loss is approximately expressed as a funtion of generating powers and the generalized generation factor. From this expression, the Jacobian matrix is formulated and solved by the Newton Raphson Method. In this method, the economic dispatch problem is solved rapidly without calculating the penalty factor. The proposed method has fast convergency characteristic and good accuracy. The feasibility of this method is demonstrated by means of examples.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.5
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• pp.94-99
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• 2015

Prediction algorithm of the energy storage system in accordance with the load pattern can cause economic loss in case of a failure prediction. In addition, algorithm that uses TOU(Time of Use) based on the revelation by the power electric charge which covers most simply is an inefficient operation because it is only for the purpose of reducing the peak power. In this paper, we introduced a non-prediction algorithm with a conventional TOU in order to solve this problem operating the energy storage system economic and efficient.

• East Asian Economic Review
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• v.27 no.2
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• pp.115-143
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• 2023

In this paper, we address how the monetary authority should react to financial market status and exchange rate movements in a small open economy New Keynesian model with financial frictions due to asymmetric information between savers and borrowers. We show that the small economy with financial frictions is more susceptible to the exogenous shocks under the fixed exchange rate regime than under the flexible exchange regime. The small economy experiences a more prolonged and deeper economic recession under the fixed exchange rate regime than under the flexible exchange rate regime. The monetary policy taking into account external finance premium is better than the interest rate rule without considering the financial market status.

• Structural Engineering and Mechanics
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• v.85 no.4
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• pp.461-468
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• 2023

Edible coatings are one of the most innovative methods to preserve the quality and increase the shelf life of fresh fruits and vegetables. A successful edible coating should have a barrier against gases, especially oxygen and water vapor, and have good surface characteristics. Today, chitosan coating is widely used due to its properties, such as non-toxic, biodegradable, and biocompatibility. Is. Coating the surface of fruits and vegetables with chitosan increases shelf life due to reducing weight loss and reducing respiration rate and also reduces decay due to its antimicrobial and anti-fungal effect. This work discusses the effect of using chitosan coating containing chamomile extract to increase fresh vegetables'shelf life. In addition to increasing the shelf life of vegetables, this method can be used as a solution for the economic management of human resources. The results of this method confirm the successful synthesis of these nanoparticles, and the results of applying this food coating on vegetables have been successful. They have increased the shelf life of vegetables such as basil and spinach.

• Korean Journal of Agricultural Science
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• v.49 no.4
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• pp.737-747
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• 2022

The purpose of this study is to analyze farmers' perceptions of Greenhouse Gas Reduction Projects and identify factors influencing participation in the projects. To achieve the research objective, a survey was conducted and a probit model was adopted for the empirical analysis. The results showed that farmers do not participate in the projects due to a lack of education and promotion and due to economic loss. It also showed that the frequency of training and technical guidance learning, degree of recognition of the need for efforts to reduce greenhouse gases, and the level of recognition of the projects concerned have a positive impact on the willingness to participate in the projects. Meanwhile, participation in agricultural environment conservation programs has a negative impact on it. Enhancement of education and promotion as well as economic support (direct payment, R&D) would be useful to raise the willingness to participate in the projects.