• Journal of Korean Society for Atmospheric Environment
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• v.16 no.4
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• pp.327-338
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• 2000

complexity in atmospheric environment coupled with shoreline and complex terrain often causes local variations of meteorology that are distinct from those representative over larger surrounding area, These kinds of local variations are less significant in usual long-term environmental impact analyses dealing with continuous plume. The variations could however be crucial in predicting dispersion of toxic substance released in a relatively small area for a short duration. In the present paper the effects of spatial and temporal resolution of diagnostic wind field on the dispersion of the released substance are investigated by using a puff model. A hypothetical release scenario assumes that a substance is released from a location in the Yochon Industrial Estate and passively dispersed within a few-kilometer distance for an hour. The results show that diagnostic analysis could resolve more spatial variations to some extent by employing smaller grid size. The peak concentrations and puff trajectories obtained from spatially -and/or tmeporally -varing diagnostic wind field are found appreciably different from those obtained from uniform wind field. Attention to high-resolution wind field in the both spatial and temporal spaces is called in the consequence analysis of toxic substance release.

• Journal of Auto-vehicle Safety Association
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• v.11 no.1
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• pp.23-29
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• 2019

Recently, use of composite materials has been increasing for body structures and chassis parts in the car industry because of weight reduction effect and excellent mechanical thermal characteristics. However, application of composite materials in brake system is very difficult because it is hard to obtain enough brake performance due to low heat storage capacity of the composite materials. In this paper, we will present new carbon ceramic composite disc with high flow characteristic. To obtain this characteristic, new vent structures were designed by using ARIZ method and substance-field model analysis. The flow effect of these vent structures on the brake performance was verified by pugh matrix and cooling test. The test results show improvement of cooling performance up to $30^{\circ}C$. Finally, These results will improve brake the reliability of the brake performance for the high performance vehicles and electric vehicles.

• Journal of Magnetics
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• v.20 no.3
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• pp.252-257
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• 2015

This paper investigates the concept and implementation of an energy harvesting device using a ferrofluid sloshing movement to generate an electromotive force (EMF). Ferrofluids are often applied to energy harvesting devices because they have both magnetic properties and fluidity, and they behave similarly to a soft ferromagnetic substance. In addition, a ferrofluid can change its shape freely and generate an EMF from small vibrations. The existing energy harvesting techniques, for example those using piezoelectric and thermoelectric devices, generate minimal electric power, as low as a few micro-watts. Through flow analysis of ferrofluids and examination of the magnetic circuit characteristics of the resultant electromagnetic system, an energy harvester model based on an electromagnetic field generated by a ferrofluid is developed and proposed. The feasibility of the proposed scheme is demonstrated and its EMF characteristics are discussed based on experimental data.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.27
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• pp.183-213
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• 2005

This study is achieving overseas investment to be kept and manages important position in business scope because Korean Company achieves business in major market in world and goes forward. under proposition that development(foreign direct investment) previous engagement can not but differ with advanced nation enterprise's model in over sea direct investment achievement. Grasp ramification(pattern change substance) of overseas direct investment since the 1990 to korean manufacture Firm(enterprise). Seek political consultation by analyzing change of factor and investment decision factor by year in dimension by industry investment winter season by year affecting in oversea direct investment and was attained in purpose to verify existent theory's explanation power connected with investment previous engagement. This is that can develop and procure competitive advantage of enterprise peculiarity by making overseas direct investment adversely with existent theory that can make foreign country direct investment though there is high position of enterprise characteristic's competitive advantage and move of knowledge and information is important in korean firm's overseas direct investment in globalization roadbed in at least own field through change and renovation establish experiment model under proposition that should grope more active previous engagement than advanced nation enterprise and arranged subject of study if it is korean's firm that wish to become universal guidance enterprise. and examine trend of direct investment and actual conditions invested first in the foreign countries as examples by investment department, by investment industry inside of investment scale etc..., establish korean firm's invest area selection and decision and investment very important person and effect analysis Circumstance-model that is based in strategic adaptedness by year. Circumstance-variable have influenced how in overseas direct investment and decision and what variable will be considered first in over sea direct investment did Empirical analysis in here after

• The Journal of the Korea Contents Association
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• v.22 no.1
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• pp.99-115
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• 2022

In this study, domestic academic journal papers on tax compliance, tax consciousness, and faithful tax payment (hereinafter referred to as "tax compliance") were comprehensively analyzed from an interdisciplinary perspective as a representative research topic in the field of tax science. To achieve the research purpose, topic modeling technique was applied as part of text mining. In the flow of data collection-keyword preprocessing-topic model analysis, potential research topics were presented from tax compliance related keywords registered by the researcher in a total of 347 papers. The results of this study can be summarized as follows. First, in the keyword analysis, keywords such as tax investigation, tax avoidance, and honest tax reporting system were included in the top 5 keywords based on simple term-frequency, and in the TF-IDF value considering the relative importance of keywords, they were also included in the top 5 keywords. On the other hand, the keyword, tax evasion, was included in the top keyword based on the TF-IDF value, whereas it was not highlighted in the simple term-frequency. Second, eight potential research topics were derived through topic modeling. The topics covered are (1) tax fairness and suppression of tax offenses, (2) the ideology of the tax law and the validity of tax policies, (3) the principle of substance over form and guarantee of tax receivables (4) tax compliance costs and tax administration services, (5) the tax returns self- assessment system and tax experts, (6) tax climate and strategic tax behavior, (7) multifaceted tax behavior and differential compliance intentions, (8) tax information system and tax resource management. The research comprehensively looked at the various perspectives on the tax compliance from an interdisciplinary perspective, thereby comprehensively grasping past research trends on tax compliance and suggesting the direction of future research.

• Korean Journal of Biological Psychiatry
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• v.20 no.2
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• pp.54-60
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• 2013

Objectives The purpose of this study is to find the influential clinical and physical characteristics which affect apnea-hypopnea index (AHI) in suspected obstructive sleep apnea (OSA) patients. Methods We evaluated the comprehensive factors including sleep related symptoms, clinical scales, medical history, substance use, and anthropometric data of the 119 participants who complained of the symptoms of OSA. All the participants underwent attended-full night laboratory polysomnography. The correlation and multiple regression analysis were conducted to find the influential and predictive factors of AHI. Results A multiple linear regression model 1 showed that higher AHI was associated with higher body mass index (BMI)(p < 0.001) and higher frequency of observed apnea (p = 0.002). In multiple linear regression model 2, AHI was associated with higher BMI (p < 0.001) and loudness of snoring (p = 0.018). Conclusions The present preliminary results suggest that BMI and observed apnea are most influential factors that affect AHI in suspected OSA patients. In the future study we will design the prediction formula for the OSA and AHI, which is useful in the clinical medical field.