• Journal of Korean Society for Atmospheric Environment
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• v.28 no.6
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• pp.675-687
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• 2012

Applying an external electric field across air filter media is one of methods to improve the filtration performance. Metal wire meshes have been commonly used as electrodes situated on both sides of a thick filter pad. For a thin filter medium a short circuit, known as the biggest drawback for applying an external electric field to air filter, can occur at the closest point between electrodes. In this study several types of insulated meshes were prepared by coating #50 meshes with a dielectric material, Nylon 66, and the filtration property of air filter was evaluated at the presence of external electric field using those insulated meshes as electrodes and compared with that of filters using bared meshes. The collection efficiency of tested filter was increased from 78% to 95% for singly charged 100 nm particles by application of external electric field. As a result, there was no significant difference in collection efficiency between filters with insulated and bared electrodes. Similar results could be also seen from the tests using polydisperse particles. Finally, through this study, we found that the insulation of mesh electrodes doesn't affect the filtration performance of fibrous air filter under external electric field.

• Journal of Korean Society on Water Environment
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• v.28 no.5
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• pp.663-668
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• 2012

The feasibility of enhancing biological nutrient removal from an industrial wastewater was tested with food waste leachate and sugar liquid waste as external carbon sources. Long term influences of adding external carbon sources were investigated to see how the biological nutrient removal process worked in terms of the removal efficiency. The addition of the external carbons led to a significant improvement in the removal efficiency of nutrients: from 49% to approximately 76% for nitrogen and from 64% to around 80% for phosphorus. Approximately, 20% of the removal nitrogen was synthesized into biomass, while the remaining 80% was denitrified. Though the addition of external carbon sources improved nutrient removal, it also increased the waste sludge production substantially. The optimal observed BOD/TN ratio, based on nitrogen removal and sludge production, was around 4.0 in this study.

• KIEAE Journal
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• v.16 no.3
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• pp.103-112
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• 2016

Recently, many New Han-oks have been constructing in all over the country to popularize as a type of green house. But, achievement of thermal performance of external wall is still the very important issue to become popular. Purpose: The purpose of this study is to verify the thermal performance level of modern New Han-ok through Temperature Difference Ratio inside(TDRi) analysis at corners of the external wall in Han-ok. Method: To achieve this goal, measurements were carried out in 12 Han-oks(experimental mock-up(1), exhibition Han-ok(1), happy village Han-oks(10)) by taking a infra-red thermography using thermal video system. Following are analysis items about connection joint between wall and wood columns of external wall conditions; the part between external wall and external wall(2D), external wall and ceiling(or floor)(2D), 2 external walls and ceiling(or floor)(3D) and so on. Result: It was analyzed that the probability of condensation at most of connection joint appear high and TDRi of 3D corners is higher than that of 2D corners in general. It means that the development of construction techniques about connection joint between wood columns and external wall is still required. The results of this study may be used to improve the construction technology of new Han-ok and as a basis for the specifying the desired thermal comfort environment of dwelling.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.3
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• pp.37-44
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• 2012

In this paper, the application of robust fuel gauge algorithm in the external environment to general fuel gauge system is proposed. The proposed fuel gauge system is composed of two modules which are Moving Average Filter (MAF) and Inclination Filter (IF). They are used to show correctly the amount of fuel in the external environment which are curve road, slope or acceleration/deceleration driving. In parallel, verification and validation processes using Software In the Loop Simulation (SILS) in personal computer and Hardware In the Loop Simulation (HILS) similar to actual vehicle environments are established. Through this research, it turned out to be possible to operation of gauge become correct of external environment.

• Journal of the Korean Institute of Educational Facilities
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• v.15 no.2
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• pp.4-15
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• 2008

The purpose of this study was to evaluate the characteristics of daylighting environment in classroom of an school building due to the external shading devices such as fixed louvers, light shelves and exterior venetian blinds. In this study, we have made a field research with regard to the facade design in classroom of an school building. And we have made a classification of external shading devices considering the design parameters. Finally, through RADIANCE simulation, we have calculated the spatial distribution of illuminance, uniformity ratio of illuminance and daylight factors. The results of this study will provide the building designer with the basic daylighting performance data at early design stages.

• International Journal of Computer Science & Network Security
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• v.22 no.11
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• pp.51-56
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• 2022

The main purpose of the study is to analyze the features of ensuring the financial and economic security of the state in an aggressive external environment. The concept of financial and economic security should contain the priority goals and objectives of ensuring security, ways and methods to achieve them, adequately reflecting the role of finance in the socioeconomic development of the state. Its content is designed to coordinate nationwide actions in the field of security at the level of individual citizens, business entities, industries, sectors of the economy, as well as at the regional, national and international levels. The methodology includes a number of scientific and theoretical methods of analysis. Based on the results of the study, the key aspects of the system for ensuring the financial and economic security of the state in an aggressive external environment were identified.

• Asia Marketing Journal
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• v.17 no.3
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• pp.73-103
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• 2015

According to Resource Dependence theory, an organization's behavior and strategy is affected by external resources. An organization has diverse resources interacting with environment. Because organization cannot focus on all those resources, it concentrates on its critical resources. In market environment, firm responds to other firms by controlling their internal critical resources or manages interdependency with environment to get market share. Thus Firm should choose best behavior and strategy when internal and external resources are change. When new brand enters, incumbents might change their strategy to protect their market share depending on critical value. More precisely, incumbents sharing market with entrant respond, but incumbents having competitive internal resources do not. In this article, we study incumbent's responses to a new brand entry and long-term effect. We show that how incumbents change their price strategy in reaction to the new brand' entry and also show these responses vary depending on interdependency of internal resources and external environments and ownership.

• KIEAE Journal
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• v.2 no.4
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• pp.21-26
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• 2002

Modem architecture represent a great capitalistic, polishing, high-technology image to the public by design. As a result, glass architecture which show 'transmittance' in desinging play a leading part, consequently a role of machine is increasing in controlling an internal environment of building. These movement look like assisting an universal standard building disregarding a each nation's climate peculiarity, if glass building is applied by a proper external shading device. the shading device has a great effect on the reduction of cooling load energy, this research to propose the proper designing scheme of the fixed external shading device. The effect of proper external shading device on the cooling load is evaluated by the numeric simulation.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.793-808
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• 2009

This paper presents procedure and prediction method of internal and external stabilities when designing D.C.M, with main factors to be considered, such as chemical reaction of additive, physical properties of stabilized body and mixing strength. Results show that through case studies, a design unconfined compressive strength of stabilized body (hereafter referred to as 'compressive strength') directly depends on the quantity of cement, which is decided by laboratory test, and the compressive strength enormously affects internal and external stabilities. So laboratory mixing test to obtain the compressive strength for design allowable stress should be given careful considerations.

• Human Ecology Research
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• v.60 no.4
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• pp.497-505
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• 2022

This study aims to examine the mediating role of peer attachment between affective school environments and the problematic behaviors of children using data from the Panel Study on Korean Children 10th wave (2017). Descriptive statistics, reliability analysis, correlation analysis, multiple regression analysis, Sobel test, and bootstrapping versification were performed using SPSS 28.0 and Process Macro 28.0. The results indicate that controlled and rigid school environments were negatively associated with peer attachment and positively associated with both internal and external behavior problems. Furthermore, peer attachment was negatively associated with both internal and external behavioral problems. Peer attachment completely mediated the link between affective school environments and internal behavioral problems, and partially mediated the link between affective school environments and external behavioral problems. These results show the important role of supportive and democratic school environments regarding peer attachment.