• Nuclear Engineering and Technology
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• v.52 no.7
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• pp.1545-1556
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• 2020

Recently, the International Commission on Radiological Protection (ICRP) has developed the Mesh-type Reference Computational Phantoms (MRCPs) for adult male and female to overcome the limitations of the current Voxel-type Reference Computational Phantoms (VRCPs) described in ICRP Publication 110 due to the limited voxel resolutions and the nature of voxel geometry. In our previous study, the MRCPs were used to calculate the dose coefficients (DCs) for idealized external exposures of photons and electrons. The present study is an extension of the previous study to include three additional particles (i.e., neutrons, protons, and helium ions) into the DC library by conducting Monte Carlo radiation transport simulations with the Geant4 code. The calculated MRCP DCs were compared with the reference DCs of ICRP Publication 116 which are based on the VRCPs, to appreciate the impact of the new reference phantoms on the DC values. We found that the MRCP DCs of organ/tissue doses and effective doses were generally similar to the ICRP-116 DCs for neutrons, whereas there were significant DC differences up to several orders of magnitude for protons and helium ions due mainly to the improved representation of the detailed anatomical structures in the MRCPs over the VRCPs.

• Journal of the Korean Society of Groundwater Environment
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• v.6 no.2
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• pp.87-94
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• 1999

This study is providing Modified DRASTIC Model to which lineament density and land use are added as additional factors using geographic infomation system(GIS). and then to evaluate groundwater contamination potential of Pyungtek-Gun area in Kyunggi-Do. In this study. the reason for using additional factors is because. in case of lineament density. when we consider that most of aquifer is bedrock aquifer in hydrogeologic environment of the Korea, lineament is very important to flow of groundwater and contamination material. and because land use can reflect indirectly impact of point or non_point source in study area. For statistical analysis. vector coverage per each factor is converted to grid layer and after each correlation coefficient between factors, covariance, variance. eigenvalue and eigenvector by principal component analysis of 3 direction. are calculated. correlation between factors is analyzed. Also after correlation coefficients between general DRASTIC layer and rated lineament density layer and between general DRASTIC layer and rated land use layer are calculated. final modified DRASTIC Model is constructed by using them with each weighting. when modified DRASTIC Model was compared with general DRASTIC Model, comtamination potential in modified DRASTIC Model is fairly detailed and consequently. vulnerable area which has high contamination potential could be presented concretly.

• Korean Journal of Occupational Health Nursing
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• v.27 no.1
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• pp.36-47
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• 2018

Purpose: This study aimed to examine the effects of interpersonal relationship ability, job stress, and stress coping type on the turnover intention of nurses in the early stage of their careers. Methods: Data were collected from 136 early stage nurses from two general hospitals and one tertiary hospital in Chungbuk province. An early stage nurse was defined as the nurse with a work experience of 3 to 36 months. The collected data were analyzed using independent t-test, one-way ANOVA, Mann-Whitney U test, Person's correlation coefficient, and stepwise multiple regression. Results: It was seen that turnover intention had a negative correlation with interpersonal competency (r=-.20, p=.020) and a positive correlation with job stress (r=.56, p<.001). Job stress due to work over load, inadequate compensation and working environment, interpersonal relationship ability, and length of clinical career were significant factors influencing turnover intention (p<.05). These variables explained for 50.4% of the variance in turnover intention. Conclusion: It is necessary to develop an interpersonal relationship ability improvement program to decrease turnover intention among early stage nurses by helping them to successfully adapt to their job. Moreover, it is important to bring about continuous improvements in terms of provision of adequate workload and appropriate rewards, and creation of a suitable work environment to reduce the job stress of early stage nurses.

• Journal of Information Display
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• v.3 no.1
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• pp.6-10
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• 2002

We have synthesized a new green Ir(III) complex fac-tris-(3-methyl-2-phenyl pyridine)iridium(III) $Ir(mpp)_3$ and fabricated phosphorescent polymer light-emitting device using it as a triplet emissive dopant in PVK. $Ir(mpp)_3$ showed absorption centered at 388 nm corresponding to the $^1MLCT$ transition as .evidenced by its extinction coefficient of the order of $10^3{\cdot}$ From the PL and EL spectra of the $Ir(mpp)_3$ doped PVK film, the emission maximum was observed at 523 nm, due to the radiative decay from the $^3MLCT$ state to the ground state, confirming a complete energy transfer from PVK to $Ir(mpp)_3$. The methyl substitution has probably caused a red shift in the absorption and emission spectrum compared to $Ir(mpp)_3$. The device consisting of a 2 % doped PVK furnished 4.5 % external quantum efficiency at 72 $cd/m^2$ (current density of 0.45 $mA/cm^2$ and drive voltage of 13.9 V) and a peak luminance of 25,000 $cd/m^2$ at 23.4 V (494 $mA/cm^2$). This work demonstrates the impact of the presence of a methyl substituent at the 3-position of the pyridyl ring of 2-phenylpyridine on the photophysical and electroluminescence properties.

• Korean Journal of Adult Nursing
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• v.29 no.1
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• pp.41-50
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• 2017

Purpose: The purpose of this study was to identify and compare the factors influencing attitude toward one's own aging among Korean middle-aged adults and the elderly. Methods: A cross sectional study was performed with a total sample of 70 middle-aged adults and 64 elderly reside in two metropolitan areas. Data were collected from August 2015 to November 2015 using the Perceived Health Status Scale, the Health Locus of Control Scale and the Attitude Toward own Aging (ATOA) Scale. The statistics used include percentage, t-test, Pearson's correlation coefficient, and multiple regression. Results: Mean age for each age group were about 52 and 76 years old for middle-aged adults and the elderly respectively. A considerable proportion of all participants reported a negative attitude toward aging. Perceived health status was the common factor influencing attitude toward one's own aging in both age groups. Middle-aged adults identified presence of chronic illness and internal health locus of control as important factors. In contrast, the elderly reported that education and others-dependent health locus of control such as powerful others had a significant impact on ATOA. Each regression model explained 31% and 55% of the total variance of ATOA among middle-aged adults and among the elderly. Conclusion: Both middle-aged adults and the elderly with low perceived health status are at risk of negative ATOA's. The type health locus of control need to be identified and utilized based on individuals' tendency to improve positive ATOA. That is, middle-aged adults might need reinforcement of their self-will whereas the elderly might need enhancement of social support and network of family and healthcare providers.

• Journal of the Korean Society for Railway
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• v.14 no.3
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• pp.203-210
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• 2011

This study formulates the theoretical wheel-set model to evaluate wheel-climbing derailments of rolling stock due to collision, and verifies this theory with dynamic simulations. The impact forces occurring during collision are transmitted from a car body to axles through suspensions. As a result of combinations of horizontal and vertical forces applied to axles, rolling stock may lead to derailment. The derailment type will depend on the combinations of the horizontal and vertical forces, flange angle and friction coefficient. According to collision conditions, the wheel-lift, wheel-climbing or roll-over derailments can occur between wheel and rail. In this theoretical derailment model of wheelset, the wheel-climbing derailment types are classified into Climb-over, Climb/roll-over, and pure Roll-over according to derailment mechanism between wheel and rail, and we proposed the theoretical conditions to generate each derailment mechanism. The theoretical wheel-set model was verified by dynamic simulations.

• Ecology and Resilient Infrastructure
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• v.5 no.3
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• pp.145-155
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• 2018

In a monsoonal climate, the soil seed bank can play an important role in plant regeneration after the severe annual floods that disturb above-ground vegetation within the riparian zone. To investigate the relationship between the soil seed bank and vegetation, we measured the species composition of the soil seed bank and the extant above-ground vegetation in six major plant communities (Artemisia selengensis, Miscanthus sacchariflorus, Persicaria nodosa, Phalaris arundinacea, Phragmites japonica, and Rorippa palustris) in the Cheongmicheon Stream, Korea. A total of 21 species germinated from the floodplain soil seed banks. The most diverse seed bank (21 species) was found in the A. selengensis community, wheres the lowest number of species was found in the R. palustris community (2 species). Most soil seed banks were composed of annuals (90%), exceptions being Rumex crispus and Artemisia princeps, which are perennial ruderals. The similarity of species composition between the soil seed bank and above-ground vegetation was low with Sorensen's similarity indices averaging 29% (range 12 - 42%). Crucially, existing dominant perennials of the extant vegetation including A. selengensis, M. sacchariflorus, P. japonica and P. arundinacea were absent from the soil seed bank. In conclusion, the soil seed banks of the floodplains of the Cheongmicheon Stream were mainly composed of viable seeds of ruderal plants, which could germinate rapidly after severe flood disturbance. The soil seed bank may, therefore, be useful for the restoration of the early succession stages of riparian vegetation after flood disturbances.

• Physical Therapy Korea
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• v.17 no.2
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• pp.33-42
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• 2010

The aim of this study was to investigate correlations of the Trunk Control Test (TCT), Postural Assessment Scale for Stroke (PASS-TC), and Trunk Impairment Scale (TIS) and to compare the TCT, PASS-TC, TIS and its subscales in relation to balance, gait and functional performance ability after stroke. Sixty-two stroke patients attending a rehabilitation program participated in the study. Trunk control was measured with the use of TCT, PASS-TC, TIS balance (Berg Balance scale; BSS), gait ability (10 m walk test), functional performance ability (Tuned Up and Go Test TUG) and the mobility part of the Modified Barthel index (MBI), Fugl Meyer-Upper/Lower Extremity ($FM-U{\cdot}L/E$), The scatter-plot (correlation coefficient) was composed for the total scores of the TCT, PASS-TC, and TIS. The multiple regression analysis was performed to evaluate the impact of trunk control on balance, gait, and functional performance ability. Twenty eight participants (45.2%) and twenty participants (32.3%) obtained the maximum score on the TCT and PASS-TC respectively; no subject reached the maximum score on the Trunk Impairment Scale. There were significant correlations between the TIS and TCT (r=.38, p<.01), PASS-TC (r=.30, p<.05), TCT and PASS-TC (r=.59, p<.01). Stepwise multiple regression analysis showed that the BBS score (${\beta}=.420{\sim}.832$) had slightly more power in predicting trunk control than the $FM-U{\cdot}L/E$. TIS-dynamic sitting balance, TUG and the MBI-mobility part. This study 치early indicates that trunk control is still impaired in stroke patients. Measures of trunk control were significantly related with values of balance, gait and functional performance ability. The results imply that management of trunk rehabilitation after stroke should be emphasized.

• Korea Journal of Hospital Management
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• v.19 no.2
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• pp.73-88
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• 2014

Objective: This research investigates how to increase the quality of medical service and supply high quality of medical service to patients. By using Kano Model theory we examines what medical service attributes the hospital would be conducted preferentially for patient's satisfaction and provides informations of management strategies for hospitals. Method: To study patients' perception of medical service quality, first we performed pilot test to derive 30 medical service attributes. With 30 medical service attributes, we conducted survey of 300 subjects who have experienced medical services in 6 months. To examine patients' conception of medical services, a modified Kano's questionnaire using 5 scale is applied. Finally we calculated SI(Satisfaction index) and DI(Dissatisfaction index) and PCSI(Potential Customer Satisfaction Improvement) index with Kano's Model analysis results. Key Findings: We found that the quality of medical service categorized in 15 one-dimensional elements, 9 must-be elements and 6 indifferent elements. Moreover the attribute of gives prompt services and have patient's best interest at heart scored the highest SI, whereas the attributes of accurate and precise medical service, exact records, enough explanation and polite attitudes are the highest score of DI. And also good explanation of the bill scored the highest PCSI. In this study findings indicate that while medical service providers try to increase patients' satisfaction by improving hospital's environments, patients' perception of trust and good interpersonal relationships with medical service providers have strong and positive impact on patients' satisfaction.

• Geomechanics and Engineering
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• v.20 no.1
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• pp.19-28
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• 2020

The spatial variability of geotechnical properties can lead to the uncertainty of settlement for frozen soil foundation around the oil pipeline, and it can affect the stability of permafrost foundation. In this paper, the elastic modulus, cohesion, angle of internal friction and poisson ratio are taken as four independent random fields. A stochastic analysis model for the uncertain settlement characteristic of frozen soil foundation around an oil pipeline is presented. The accuracy of the stochastic analysis model is verified by measured data. Considering the different combinations for the coefficient of variation and scale of fluctuation, the influences of spatial variability of geotechnical properties on uncertain settlement are estimated. The results show that the stochastic effects between elastic modulus, cohesion, angle of internal friction and poisson ratio are obviously different. The deformation parameters have a greater influence on stochastic settlement than the strength parameters. The overall variability of settlement reduces with the increase of horizontal scale of fluctuation and vertical scale of fluctuation. These results can improve our understanding of the influences of spatial variability of geotechnical properties on uncertain settlement and provide a theoretical basis for the reliability analysis of pipeline engineering in permafrost regions.