• Journal of Environmental Health Sciences
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• v.27 no.4
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• pp.63-71
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• 2001

PM 2.5/ samples were measured at two sites, Hadan(suburban site) and Anrak (roadside site) in Busan area. PM 2.5/ sampling was performed for 24-hour intervals by the FH9.5 particulate sampler. Aerosol samples were collected on PTFE filter. A total of 60 particulate samples were collected, dad samples were measured for Particulate mass concentration, metallic elements (Cr, Mn, Ni. Cu. Se, Fe, Pb, and Zn) and waer-soluble elements (C $l^{[-10]}$ , N $O_{3}$$^{[-10]}$ ,S $O_{4}$$^{2-}$, N $H_{4}$$^{+}$, $Ca_{2}$$^{+}$, $Mg_{2}$$^{+}$ and $^{+}$.Mass concentration in Hadan ranged 24.23~57.12 $\mu\textrm{g}$/㎥ and 60.22~72.12 $\mu\textrm{g}$/㎥m Yellow Sand Events. Major cations in Hadan and Anrak site is N $H_{4}$$^{+}$and N $a^{+}$ respectively. SO42$^{[-10]}$ was the abundant specie in the PM 2.5 fraction for Hadan site an dAnrak site. Hadan site showed igher concentration in S $O_{4}$$^{2.1}$ and N $H_{4}$ $^{+}$ In Anrak site the concentration of S $O_{4}$/sip 2-/and N $a^{+}$ was higher than other ions Prominent metallic elements were Fe and Pb in two sites. Principal component analysis showed that main source of PM 2.5 aerosol particles was non-metal related source which was resulted in relating elements as Cr, Ni, and Pb at Hadan site, Anrak site also has resulted PM2.5 aerosol paricles source, which was related its element like Zn, and Ni,. The SAS package analysis also showed that long-range transport effect at Hadan area due to Yellow Sand Event by the prevailing weaterlies.ling weaterlies.

• Journal of Information Technology Applications and Management
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• v.21 no.3
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• pp.35-52
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• 2014

This study aims to examine how the relationship with an information source affects people to perceive credibility of online information. We developed a conceptual framework that explained how people perceived information credibility when they were familiar with the information source and/or when the information source seemed credible. We then compared the models in two different contexts, namely, online review and social media sites, to examine differences. We surveyed 136 online social media users with their online shopping experiences. Among our eight hypotheses, three (H6: the personality similarity between an information provider and an information seeker enhances the perceived credibility of the former; H7: the credibility of an information provider produces a much stronger mediating effect in review sites than in social media sites; H8: the familiarity of an information seeker with an information provider produces a stronger mediating effect in social media sites than in review sites) are fully supported and four (H1: the credibility of an information provider has a positive influence on the perceived credibility of the online information; H2: the familiarity of an information seeker with an information provider has a positive influence on the perceived credibility of the online information; H3: the goal similarity between an information provider and an information seeker enhances the perceived familiarity of the latter with the former; H5: the personality similarity between an information provider and an information seeker enhances the perceived familiarity of the latter with the former) are partially supported. The hypothesis of H4: the goal similarity between an information provider and an information seeker enhances the perceived credibility of the former is rejected. The result confirms that credibility of information is strongly mediated by credibility of information source than familiarity with information source in online review sites and vice versa in social media sites.

• Journal of the Korean Geotechnical Society
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• v.23 no.11
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• pp.27-37
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• 2007

Downhole seismic method is very economic and easy to operate because it uses only one borehole and simple surface source to obtain the shear wave velocity profile of a site. In this study, automatic shear wave source was developed for efficient downhole seismic testing. This source is motor-spring type and easy to control. It can lessen the labor of operator and the working time. Moreover, it can provide better and repetitive signals for data interpretation. By combining developed automatic source with automatic receiver system, PC based data acquisition system, advanced managing program, and semi-automatic downhole performing system were constructed. Through comparison test with manual source, advantages of automatic source were verified. Constructed semi-automatic downhole testing system including automatic shear wave source was applied to the soft soil site. The applicability and reliability were verified and the importance of automating testing system for obtaining reliable result was emphasized.

• The Journal of Information Systems
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• v.20 no.4
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• pp.1-22
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• 2011

This study addressed trust to collective intelligence for explaining the affecting factors to the intention to use of collective intelligence by dividing the object of trust into a Web site and an information source group. We explored the factors affecting user's continuance intention toward collective intelligence in the view off trust building. We made a well-structured survey of our proposed model and gained 205 cases. We analyzed the proposed research model empirically using partial least square method. The findings are summarized as follows. First, all key factors (relevance, timeless, completeness, understandability) composing of collective intelligence quality have a positive and significant impact on confirmation. Second, confirmation has a significant impact on trust toward a Web site, as well as toward an information source group. The last is that trust toward a Web site influences on continuance intention, whereas trust toward an information source group doesn't.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.09a
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• pp.36-45
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• 2003

Sensitivity analyses for several seismic source models were studied. For the area sources, the hazard is steeply decreasing with the source-to-site distance. Hazard is decreasing when the area of the source is increasing with fixed annual rate. For the fault sources, the fault length, distance from a site and dip angle of near fault show very sensitive effect to seismic hazard. But the various magnitude-rupture length relationships show effect to seismic hazard slightly. For the fault source with small magnitude, the exponential model is preferred rather than the characteristic model to the magnitude-recurrence law.

• The Journal of the Korea Contents Association
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• v.21 no.9
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• pp.609-621
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• 2021

This study investigates the effect of types of usual source of care on medication adherence among the elderly. Using the Korea Health Panel Survey in 2017, this study includes 3,623 elderly people 65 years of age or older taking prescription drugs for treatment of chronic diseases. The type of usual source of care was considered in three aspects: whether having a usual source of care or not, whether having a regular site only or having a regular site and doctor, size of the regular site. The types of usual source of care are heavily associated with medication adherence. Compared to those who have no usual source of care, those who have a regular site only are 1.4 times, and have both regular site and doctor are 1.8 times more likely to comply with the medication guidelines, respectively. The finding shows usual source of care has a positive effect in improving medication adherence of the elderly. The results can provide an evidence for policies for effective management of chronic diseases and efficient use of medical resources.

• Journal of Global Scholars of Marketing Science
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• v.14
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• pp.17-37
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• 2004

This research is speak that is tendencious in comprehension of external consumer information search behavior using on-line external information source to consumers who use on-line that is used as corporations' main strategic means. That is, classify consumer groups which was atomized according to type inflict consumer's information search knowledge level and shopping value study which use on-line, and decision factors of information search that these groups can influence a difference or each group which use information sources grasped what it is. Result that investigate information search knowledge level difference about study finding on-line information source utilization used mainly portal site, comparison site, auction site. And, utilization shopping pursuit value group used information source by portal site, auction site, niche shopping mall site and hedonic shopping pursuit value group used information source by portal site, auction site, shopping mall site. It confirmed that all variables(i.e. consumer-based variable and web site-based variable) are influencing variously in on-line external information search types. Finally, we proposed different way to erect strategic model about consumers that use on-line with study finding that see.

• Geomechanics and Engineering
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• v.4 no.1
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• pp.1-18
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• 2012

The spatial variation of ground motion in Kolkata Metropolitan District (KMD) has been estimated by generating synthetic ground motion considering the point source model coupled with site response analysis. The most vulnerable source was identified from regional seismotectonic map for an area of about 350 km radius around Kolkata. The rock level acceleration time histories at 121 borehole locations in Kolkata for the vulnerable source, Eocene Hinge Zone, due to maximum credible earthquake (MCE) moment magnitude 6.2 were generated by synthetic ground motion model. Soil investigation data of 121 boreholes were collected from the report of Soil Data Bank Project, Jadavpur University, Kolkata. Surface level ground motion parameters were determined using SHAKE2000 software. The results are presented in the form of peak ground acceleration (PGA) at rock level and ground surface, amplification factor, and the response spectra at the ground surface for frequency 1.5 Hz, 3 Hz, 5 Hz and 10 Hz and 5% damping ratio. Site response study shows higher PGA in comparison with rock level acceleration. Maximum amplification in some portion in KMD area is found to be as high as 3.0 times compared to rock level.

• Earthquakes and Structures
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• v.17 no.6
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• pp.557-566
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• 2019

The evaluation of the seismic hazard for a given site is to estimate the seismic ground motion at the surface. This is the result of the combination of the action of the seismic source, which generates seismic waves, the propagation of these waves between the source and the site, and site local conditions. The aim of this work is to evaluate the sensitivity of dynamic response of extended structures to spatial variable ground motions (SVGM). All factors of spatial variability of ground motion are considered, especially local site effect. In this paper, a method is presented to simulate spatially varying earthquake ground motions. The scheme for generating spatially varying ground motions is established for spatial locations on the ground surface with varying site conditions. In this proposed method, two steps are necessary. Firstly, the base rock motions are assumed to have the same intensity and are modelled with a filtered Tajimi-Kanai power spectral density function. An empirical coherency loss model is used to define spatial variable seismic ground motions at the base rock. In the second step, power spectral density function of ground motion on surface is derived by considering site amplification effect based on the one dimensional seismic wave propagation theory. Several dynamics analysis of a curved viaduct to various cases of spatially varying seismic ground motions are performed. For comparison, responses to uniform ground motion, to spatial ground motions without considering local site effect, to spatial ground motions with considering coherency loss, phase delay and local site effects are also calculated. The results showed that the generated seismic signals are strongly conditioned by the local site effect. In the same sense, the dynamic response of the viaduct is very sensitive of the variation of local geological conditions of the site. The effect of neglecting local site effect in dynamic analysis gives rise to a significant underestimation of the seismic demand of the structure.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.14 no.3
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• pp.221-230
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• 2002

In this study, in-situ performance test of an air source heat pump which has a arted capacity of 10 RT is carried out. Since test conditions, such as indoor and outdoor air conditions cannot be controlled to satisfy the standard test conditions, experiments are done with the inlet air conditions as they exist. To estimate the performance for other conditions, he heat pump is modeled with a small number of selected parameters. The values of the parameters are determined from the few measurements measured on-site during normal operation. A simulation program is developed to calculate cooling capacity and power consumption t any other operating conditions. The simulation results are in good agreement with the experiment. This study provides a method of an on-site performance diagnosis of an air source heat pump.