• Journal of Communications and Networks
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• v.5 no.4
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• pp.290-302
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• 2003

Ultra wide band (UWB) radio has recently attracted increased attention due to its expected unlicensed operation, and potential to provide very high data rates at relatively short ranges. In this article we briefly describe some main candidate multiple access and modulation schemes for UWB communications, followed with their power spectral density calculation and properties. We also present some illustrative capacity results, and provide a discussion of the impact of network topology on multiple access capacity.

• Asia pacific journal of information systems
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• v.11 no.1
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• pp.25-43
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• 2001

The evolution of EDI has opened the flexible and efficient way for business to conduct a greater portion of the routine buyer-seller business activities online. This study focuses on the role of factors that change the innovation characteristics for implementation success of EDI. Three factors promotional efforts, proactive implementation strategy, and provision of technical expertise are proposed to affect EDI implementation success, as these factors directly influence three general and most important attributes of innovation relative advantage, compatibility, and complexity respectively. Hypotheses indicate that promotional efforts, proactive implementation strategy, and provision of technical expertise directly affect EDI implementation success that is represented by three variables volume, depth, and diversity. A structural equation modeling approach(LISREL) is used to analyze data from EDI adopters. The results show that proactive implementation strategy and provision of technical expertise positively affect implementation success of EDI. Given the significant impact of the wide spread use of the EDI system, this study offers quite useful insights on the factors facilitating innovation characteristics under which EDI can be successfully diffused in organizations.

• Journal of Environmental Impact Assessment
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• v.20 no.2
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• pp.199-205
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• 2011

The Saemangeum embankment construction have changed the flowing on the topography of the coastal marine environment. However, the variety of ecological factors are changing from outside of Saemangeum embankment area. The ecosystem of various marine organisms have led to changes by sea surface temperature. The aim of this study is to monitoring of sea surface temperature(SST) changes were measured by using thermal infrared satellite imagery, MODIS and Landsat. The MODIS data have the high temporal resolution and Landsat satellite data with high spatial resolution was used for time series monitoring. The extracted informations from sea surface temperature changes were compared with the dyke to allow them inside and outside of Saemangeum embankment. The spatial extent of the spread of sea water were analyzed by SST using MODIS and Landsat thermal channel data. The difference of sea surface temperature between inland and offshore waters of Saemangeum embankment have changed by seasonal flow and residence time of sea water in dyke.

• Journal of the Korean Society of Safety
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• v.27 no.3
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• pp.176-181
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• 2012

In this research the 2009 spring occurred during forest fire ImSil and research destination GyeongJu has been selected. Research in the field of the target time exploratory Boundary Data through after air photos, satellite photos and topographic map by using the combustion area was calculated. 2009 March 1-forest fire occurs on the day of the weather information and weather changes wildfire in the check in any affected. Study research destination of combustion is ImSil 161 ha, GyeongJu 270.93 ha. The impact of the weather-temperature dry weather forest fires this favorable situation to occur and the wind directions and the spread of the mountain wind speed was less impact has no arguments.

• Journal of Environmental Impact Assessment
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• v.21 no.1
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• pp.133-142
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• 2012

Convection Current Circulation System(CCCS) in stratified reservoir controls development of anaerobic condition and algal bloom during summer. In order to increase the CCCS effectiveness, we analyze diverse design parameters to make optimize the flow pattern in reservoir. In this study, we interpret the internal flow with installation and operation condition of CCCS based on CFD in reservoir. Design variables of CCCS is reservoir depth, stratification strength, distance of between CCCS and so on. Since reservoir depth and stratification strength in variables is depending on natural phenomenon, we evaluated current circulation effect by distance of CCCS and proposed the optimal design condition using CFD simulation. Flow and diffusion changes in water body was assessed by temperature and dye test. Changes in water floor temperature at 40m intervals was slowly descending over 37 hours. Dye diffusion simulation at 60m intervals, the radius of the spread between two devices were overlapped after 12 hours.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.10
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• pp.159-164
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• 2021

The COVID-19 pandemic has widely spread and has become a global problem. The pandemic has had a negative impact on most countries and on the global economic growth. In the real estate and housing market, the impact of the pandemic has directly disrupted the supply of raw materials and human resources. In case of Vietnam, the real estate and housing markets are increasingly becoming important contributors to Vietnam's economy, with a combined contribution of approximately 6% to the GDP of the country. Also, the pandemic has negatively affected the real estate in Vietnam. Using a sample data of 220 home, apartment and real estate buyers in the period of April 2020 to Apr 2021 in Nam Tu Liem and Cau Giay districts, Hanoi, the research results demonstrate that the area of the house, the number of beds, and the location of the land show a positive influence on the real estate price. Meanwhile, the distance from the land to the center of the district has a negative effect on the price, which means that the further away a land is from the center, lower is its price.

• Journal of Environmental Impact Assessment
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• v.12 no.3
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• pp.199-209
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• 2003

The withdrawal method for protecting the uncontaminated part from the spread of contaminants was suggested by a simultaneous equation. The formulation of them is based upon the build up of the ridge part between the contaminated and uncontaminated parts that resulted from the efficient use of barrier wells. The quality in the withdrawn groundwater depends upon the heads at wells no. 5 and 6. The determination of pumping rates and qualities with changing the heads at wells no. 5 and 6 should be given by considering the demand for water use and the capacity and cost for removing the contained contaminants. The results of this study should be used in taking a plan for supplying water use as well as preventing the spread of contaminants from some known contaminated sources.

• PNF and Movement
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• v.16 no.3
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• pp.441-449
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• 2018

Purpose: This study aimed to compare the impact of proprioceptive neuromuscular facilitation leg patterns emphasizing hallux abduction (PNF-LPHA) on the intrinsic foot muscles of participants with hallux valgus (HV) using the toe-spread-out exercise (TSO). Methods: The present study recruited 12 individuals with HV. All the participants voluntarily agreed to participate in the study after hearing explanations of its purpose and process. All participants performed the TSO, PNF-LPHA 1, and PNF-LPHA 2. The participants' abductor hallucis (AbH), adductor hallucis (AdH), extensor hallucis longus (EHL), and flexor hallucis brevis (FHB) activity was measured, and the ratio of AbH:AdH was measured during the three interventions using electromyography. Additionally, the participants' AbH thickness was measured by ultrasonography. An intraclass correlation coefficient (ICC) was used to verify the intra-rater reliability of ultrasonography at rest and during contraction. Results: The intra-rater reliability was excellent at rest and during contraction ($ICC_{3,1}=0.90$ and $ICC_{3,1}=0.83$, respectively). There were no statistically significant differences in the activity of the AbH, the ratio of AbH: AdH, and the thickness of AbH between the TSO and PNF-LPHA2 groups. Additionally, EHL activity was significantly higher in the PNF-LPHA2 group than in the TSOgroup. Conclusion: PNF-LPHA 2 can be recommended as a method to optimize AbH and EHL activity, the ratio of AbH:AdH, and the thickness of AbH in individuals with HV.

• Korean Journal of Occupational Health Nursing
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• v.32 no.4
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• pp.215-224
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• 2023

Purpose: This study uses data from the 12th~17th Korea Welfare Panel (2017~2022) to analyze changes in depression scores due to the COVID-19 outbreak and the factors that influenced depression scores according to employment type. Methods: The difference in depression scores according to employment types before COVID-19 (12th~14th) and after COVID-19 (15th~17th) was analyzed. A fixed-effect model analysis was conducted before and after the occurrence of COVID-19. Results: After the outbreak of COVID-19, job satisfaction and family life satisfaction influenced the depression scores of regular wage workers. After the outbreak of COVID-19, annual income, health status, and satisfaction with family life affected the depression scores of non-regular wage workers. After the outbreak of COVID-19, leisure life satisfaction and family relationship satisfaction influenced the depression scores of self-employed. Self-esteem played a role as a control variable in lowering the depression scores of regular and non-regular workers, but did not play a role as a control variable for self-employed. Conclusion: Rather than the direct impact of infectious diseases such as COVID-19, social and economic changes resulting from policies implemented to prevent the spread affect workers' depression, and the impact varies depending on the type of employment. When implementing policies to prevent the spread of infectious diseases in the future, policies that take employment type into consideration rather than uniform policies should be prepared, and measures for mental health also need to be prepared.

• Asia pacific journal of information systems
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• v.25 no.1
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• pp.119-141
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• 2015

With the rapid spread of social media, video-sharing social media like YouTube has emerged as a consumption and distribution channel for entertainment goods such as music videos and movie trailers. In tourism research, there has been a lot of research of how the visual media such as movies and soap operas induced tourism. However, no studies have attempted to examine the role of social media as a music consumption channel and its impact on tourism. Expanding a body of media-induced tourism, we analysed the impact of video-sharing social media on music-induced tourism with a case of Korean pop music and inbound tourism to Korea. Developing a Web-crawler, we collected YouTube users' comments data on 166 Korean pop music video clips which were released from 2009 to 2012 with over 1 million view counts. Controlling many of the determinants of tourism and analysing country-by-country impact of YouTube comments with the panel data, we found that engagement of Korean pop music video clips on YouTube is a significant predictor for the flow of inbound tourists to Korea.