• 한국산업보건학회지
• /
• 제22권1호
• /
• pp.42-51
• /
• 2012

Objectives: To compare the exposure level of extremely low frequency (ELF) magnetic fields among semiconductor workers, shipyard welders and office workers. Methods: To measure the ELF magnetic field concentration, EMDEX LITE (Enertech, USA) were used and monitored for eight hours continuously. Five companies handling the electric and magnetic field (EMF) source were investigated, which the exposure groups were classified into three groups: semiconductor workers, welders, and office workers. Welder group was chosen as a high exposed group and office group as a low exposed group. Results: The arithmetic mean (${\pm}SD$) and geometric mean (GSD) of personal exposure level of semiconductor workers were 0.73 (${\pm}1.33$) ${\mu}T$, 0.43 (2.88) ${\mu}T$, respectively. The ceiling value ranged between 0.18 and 123.2 ${\mu}T$. Welders were exposed high with the arithmetic mean value of 3.46 (${\pm}\;13.46$) ${\mu}T$ and geometric mean value of 0.45 (4.70) ${\mu}T$, respectively, and ceiling value range of 75.5~129.6 ${\mu}T$. The exposure levels of office workers were low compared to other exposed groups; the arithmetic mean 0.05 (${\pm}0.13$) ${\mu}T$, geometric mean 0.03 (2.38) ${\mu}T$ and ceiling value range 0.37~3.35 ${\mu}T$. This study revealed statistically significant differences of the mean ELF magnetic field exposure doses among three groups (p < 0.01). Conclusions: The average ELF magnetic field exposure doses of semiconductor workers were much higher than those of office workers in control group, but were lower than those of welders in high exposure group.

• 한국병원경영학회지
• /
• 제19권3호
• /
• pp.11-28
• /
• 2014

This study, targeting Korean tertiary hospitals and general hospitals, aims to analyze how value chain model in health and medical institution suggested by Duncan and else influences on hospital management. A survey was conducted to verify the actual proof analysis of this study model. 880 questionnaires were distributed to entire 88 hospitals and 739 copies were returned from 76 hospitals. This study mainly consists of three steps to analyze the effect value chain activity has on management performance of general hospitals. For the first step, we analyzed the effects service delivery activity has on management performance. For the second step, we analyzed the effects service support activity has on management performance and for the third, we analyzed the effects interaction between service delivery activity and service support activity has on management performance. The main results of this study are as follows. First, in terms of the management performance of scale, the factors which influenced on daily charge of outpatient were service activity before treatment, at the moment of treatment and value chain activity, while more important factors in daily charge of inpatient were organizational culture, organizational structure and value chain activity. In terms of management performance of quality, the factors which influenced on the first medical examination rate of outpatient were service activity before, at the moment of and after treatment, while activity at the moment of treatment, organizational structure, and value chain activity which is interaction were more important factors in average length of stay. In terms of non-financial performance, the management performance factors which influenced on job satisfaction were service activity at the moment of, after the treatment and value chain activity, while organizational culture, strategy resources and value chain activity which is interaction were more important factors in job commitment. Secondly, all the service support activity, service delivery activity and value chain activity had statistically significant effect on management performance. Among the three factors, service support activity had relatively high effect than others.

• 한국응용과학기술학회지
• /
• 제28권1호
• /
• pp.6-9
• /
• 2011

Step feed process was analyzed stoichiometrically for the optimal operation conditions in this study. In case of optimal operation conditions, minimum R (sludge recycling) value, r (internal recycling ratio) value, and n (influent allocation ratio) value for the step feed process to acquire the maximum TN removal efficiency were identified by theoretical analysis. Maximum TN removal efficiency, based on stoichiometric reaction, can be obtained by controlling n value for the step feed process.

• 한국주거학회논문집
• /
• 제7권2호
• /
• pp.1-7
• /
• 1996

This study was designed to examine the effects of housing values on housing satisfaction model. The empirical model of this study was based on the Goulart(1982). Data were collected through questionnaire survey, and the sample consisted of 285 households in Kimhae. Housing values were grouped into four clusters : the health and convenience value, the personal and social value, the location value, and the economic value. The major findings were that 1) the concordance between values and the actual housing conditions contributes significantly to the prediction of housing astisfaction, and 2) the control variables including sociodemographic and economic characteristics and housing values themselves did not directly influence on housing satisfaction.

• 한국환경보건학회지
• /
• 제5권1호
• /
• pp.61-65
• /
• 1978

To investigate the phytoplankton distribution effected by polluted water, this research was carried out at eight sampling places in Tae-jun and one sampling place in Kang-kyong during the period from May 10 to July 25, 1977. The results are as follows. 1) The range of water temperature was 21.0~36.0$\circ$C (May 10~July 25), and pH value was in the range of 3.5~11.0. 2) BOD was generally high (140~432mg/l) 3) At the places where BOD was high, dominant species were Aphanocapsa rivularis, Microcystis aeruginosa and Oscillatoria sp. belonging to Cyanophyta, Chlorella sp. belonging to Chlorophyta, Euglena sp. belonging to Euglenophyta, and Navicula exqua and Navicula sp. belonging to Chrysophyta. 4) At the places where the range of pH value was 3.5~3.8 and the range of BOD value was 134~148mg/l, observable species were Scenedesmus ellipsoideus and Pandorina morurn belonging to Chlorophyta, Navicula exqua belonging to Chrysophyta and Euglena sp. belonging to Euglenophyta. 5) At the places where the range of pH value was 9.0~11.0 and the range of BOD value was 214~220mg/l, a few observable species were Scenedesmus carinatus, Scenedesmus ellipsoideus, Scenedesmus bijuga and Scenedesmus obundance belonging to Chlorophyta.

• 보건의료산업학회지
• /
• 제8권2호
• /
• pp.89-100
• /
• 2014

The purpose of this study was to reveal association between medical service quality, consumer satisfaction, service value and customer loyalty. Medical service quality was composed of physical quality, personal quality, technical quality, procedural quality. We thought these factors affect to the consumer satisfaction, service value and customer loyalty. For this study, 221 dental patients in Busan and Ulsan are participated in this study. The data were analyzed with descriptive statistics, t-test, ANOVA, pearson's correlation coefficients, and stepwise multiple regression analysis with SPSS 18.0 program. In conclusion, we obtained the next results. First, the influencing factor in consumer satisfaction were physical quality(${\beta}$=.519), personal quality(${\beta}$=.262), procedural quality(${\beta}$=.110), adjusted $R^2$=.537. Second, the influencing factor in service value were physical quality(${\beta}$=.253), personal quality(${\beta}$=.251), technical quality(${\beta}$=.210), procedural quality(${\beta}$=.136), adjusted $R^2$=.401. Third, the influencing factor in customer loyalty were personal quality(${\beta}$=.343), physical quality(${\beta}$=.302), procedural quality(${\beta}$=.148), adjusted $R^2$=.398. As dental patients' desire to medical service quality becomes diversified, the analysis result is considered to help the future dental service management.

• Journal of Magnetics
• /
• 제22권2호
• /
• pp.227-233
• /
• 2017

The purpose of this study was to evaluate the effects of X-ray photon energy, tissue density, and the kernel essential for image reconstruction on the image quality by measuring HU and noise. Images were obtained by scanning the RMI density phantom within the CT device, and HU and noise were measured as follows: images were obtained by varying the tube voltages, the tube currents and eight different kernels. The greater the voltage-dependent change in the HU value but the noise was decreased. At all densities, changes in the tube current did not exert any significant influence on the HU value, whereas the noise value gradually decreased as the tube current increased. At all densities, changes in the kernel did not exert any significant influence on the HU value. The noise value gradually increased in the lower kernel range, but rapidly increased in the higher kernel range. HU is influenced by voltage and density, and noise is influenced by voltage, current, kernel, and density. This affects contrast resolution and spatial resolution.

• 대한방사선기술학회지:방사선기술과학
• /
• 제42권2호
• /
• pp.119-130
• /
• 2019

Positron emission tomography (PET) is widely used imaging modality for effective and accurate functional testing and medical diagnosis using radioactive isotopes. However, PET has difficulties in acquiring images with high image quality due to constraints such as the amount of radioactive isotopes injected into the patient, the detection time, the characteristics of the detector, and the patient's motion. In order to overcome this problem, we have succeeded to improve the image quality by using the dynamic image reconstruction method based on singular value decomposition. However, there is still some question about the characteristics of the proposed technique. In this study, the characteristics of reconstruction method based on singular value decomposition was estimated over computational simulation. As a result, we confirmed that the singular value decomposition based reconstruction technique distinguishes the images well when the signal - to - noise ratio of the input image is more than 20 decibels and the feature vector angle is more than 60 degrees. In addition, the proposed methode to estimate the characteristics of reconstruction technique can be applied to other spatio-temporal feature based dynamic image reconstruction techniques. The deduced conclusion of this study can be useful guideline to apply medical image into SVD based dynamic image reconstruction technique to improve the accuracy of medical diagnosis.

• 식품보건융합연구
• /
• 제7권4호
• /
• pp.1-11
• /
• 2021

The purpose of this study is to investigate the ramen selection attributes of consumers. This research assigned taste, price, quantity, design, and brand as selection attributes, all of which have already been verified by previous studies as selection attributes when purchasing processed foods. A total of 500 questionnaires were issued, and the survey results were analysed to ensure validity and reliability. A Structural Equation Model was used to test the hypotheses of the study. Based on the analysis, taste, price, quantity, design, and brand had a statistically significant effect on satisfaction. Furthermore, satisfaction had a statistically significant effect on repurchase intention. Among the selection attributes (taste, price, quantity, design, and brand), only price had a statistically significant effect on repurchase intention. However, the influence of the selection attributes on satisfaction varied depending on the consumer's consumption value. In order to analyse the moderating effect of consumption value, the respondent group was divided into a hedonism group and pragmatism group, and analysed. It empirically proved that the hedonistic value-oriented group valued taste, and the practical value-oriented group valued price the most. This study empirically verified the relationship between ramen selection attributes and consumption value, and provided corresponding theoretical and practical implications.

• 웰빙융합연구
• /
• 제6권1호
• /
• pp.17-22
• /
• 2023

Purpose: VOCs (volatile organic compounds) are all the organic compounds that react with solar rays and increase the concentration of ozone in the troposphere and are partially also known as carcinogens. The adsorption using activated carbon is usually applied to remove VOCs. Research design, data and methodology: The 20 places of surface coating facilities were selected to evaluate the emission amount of VOCs in Seoul. In addition, the removal efficiency of VOCs in 25 places of automobile coating facilities was evaluated. Results: The average emission amount of VOCs was 10.903 kg/hr from automobile coating facilities, while 3.520 kg/hr from other surface coating facilities. The removal efficiency in adsorption with the combustion catalytic process has the mean value of 87.9% and the regeneration efficiency of activated carbon has the mean value of 95.0%. Conclusions: The removal efficiency in adsorption with the biofiltration process has the mean value of 89.8% and the regeneration efficiency of activated carbon has the mean value of 94.8%. The removal efficiency in the plasma catalyst process has the mean value of 79.3%.