• Journal of Korean Society of Environmental Engineers
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• v.29 no.7
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• pp.778-782
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• 2007

This study investigated the dechlorination mechanisms of TCE by Fe(II) associated with cement. Batch slurry experiments were peformed to investigate the behaviors of selected ions; Fe(II), Fe(III), $Ca^{2+}$, $SO_4^{2-}$ in cement/Fe(II) system. The kinetic experiments of TCE in cement/Fe(II) systems showed that injected Fe(II) was mostly sorbed on cement within 0.5 day and 90% of injected 200 mM sulfate was sorbed on cement within 0.5 day when $[TCE]_0$ = 0.25 mM and $[Fe(II)]_0$ = 200 mM. The kinetic experiments of TCE in hematite/CaO/Fe((II) systems were conducted for simulation of cement/Fe(II) system. Calcium oxide that is one of the major components in cement hydration reactions or has a reactivity in limited conditions. Hematite assumed the ferric iron oxide component of cement. The reactivities observed in hematite/CaO/Fe(II) system were comparable to those reported for cement/Fe(II) systems containing similar molar amounts of Fe(II). The behavior of Fe(II) and $SO_4^{2-}$ sorbed on solid phase at an early stage of reaction in hematite/CaO/Fe(II) system was similar to that of cement/Fe(II) system. Ferric ion was released from hematite at an early period of reaction at low pH. The experimental evidence of kinetic test using hematite/CaO/Fe(II) system implies that the reactive reductant is a mixed-valent Fe(II)-Fe(III) mineral, which may be similar to green rust. Fe(II) sorbed on cement can be converted to new mineral phase having a reactivity such as Fe(II)-Fe(III) (hydr)oxides in cement/Fe(II) systems.

• Archives of design research
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• v.18 no.2 s.60
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• pp.155-164
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• 2005

Home-service robots need to have sufficient spatial information about the surroundings for interacting with human intelligently and performing services efficiently. It is very important to investigate the efficient interaction style that supports map building task through human-robot collaboration. We first analyzed map building task with a cleaning robot and drew 4 design factors and tentative solutions, including map building procedure (task-preferred procedure/space- preferred procedure), LCD display installation (robot/robot+remote control), navigation method (push type/pull type), feedback modality(GUI/GUI+TTS). The design factors and tentative solutions were defined as independent variables and levels. This research investigated how those variables affect to the human task performance and behavior in map building tast. 8 kinds of experiment prototypes were built and usability test among 16 house wives was conducted for acquiring empirical data. As the experiment result, in terms of map building procedure, space-preferred procedure indicated better task performance than task-proffered procedure as we expected. For the LCD display installation factor, remote control with LCD display indicated higher task performance and subjective satisfaction. In robot navigation method, it was very difficult to find a significant difference between push type and pull type which contrary to our expectation. In fact, push type indicated higher subjective satisfaction. Also in feedback modality, we have acquired negative feedback an additional TTS operation guidance. It seems that robot's autonomy before achieving spatial information is rudiment condition which means users are just interacting with a mobile appliance. Thus they prefer remote-control-based interaction style in robot map building process as they used in traditional appliance control.

• The Journal of Engineering Geology
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• v.30 no.3
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• pp.237-251
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• 2020

This study examined structural analysis of supports in tunnel and displacement and underground stress of tunnel by measurement, in order to evaluate the performance of high-strength lattice girders developed as a substitute for H-profiles. According to the three-dimensional nonlinear structural analysis results of the tunnel support, the load and displacement relationship between the H-profiles and the high-strength lattice girders showed almost the same behavior, and the maximum load of the high-strength lattice girders were 1.0 to 1.2 times greater than the H-profiles. By the results of the three-dimensional tunnel cross-section analysis of the supports, the axial force was occurred largely in the lower left and right sides of the tunnel, and showed a similar trend to the field test values. In the results of the measurement of the roof settlement and rod extension, the final displacement of the steel arch rib (H-profile) and high-strength lattice girder section in tunnel was converged to a constant value without significant difference within the first management standard of 23.5 mm. According to the results of underground displacement measurement, the final change amount of the two support sections showed a slight displacement change, but converged to a constant value within the first management standard of 10 mm. By the results of measurement of shotcrete stress and steel arch rib stress, the final change amount of the two support sections showed a slight stress change, but converged to a constant value within the first management standard of 81.1 kg/㎠ and 54.2 tonf.

• Journal of Biomedical Engineering Research
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• v.25 no.4
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• pp.253-259
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• 2004

in this study, we developed a Monte Carlo imaging simulation code written by the visual C$\^$++/ programing language for design optimization of a digital X-ray imaging system. As a digital X-ray imaging system, we considered a Gd$_2$O$_2$S(Tb) scintillator and a photosensor array, and included a 2D parallel grid to simulate general test renditions. The interactions between X-ray beams and the system structure, the behavior of lights generated in the scintillator, and their collection in the photosensor array were simulated by using the Monte Carlo method. The scintillator thickness and the photosensor array pitch were assumed to 66$\mu\textrm{m}$ and 48$\mu\textrm{m}$, respertively, and the pixel format was set to 256 x 256. Using the code, we obtained X-ray images under various simulation conditions, and evaluated their image qualities through the calculations of SNR (signal-to-noise ratio), MTF (modulation transfer function), NPS (noise power spectrum), DQE (detective quantum efficiency). The image simulation code developed in this study can be applied effectively for a variety of digital X-ray imaging systems for their design optimization on various design parameters.

• Journal of Pharmaceutical Investigation
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• v.35 no.3
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• pp.179-185
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• 2005

Acebrophylline is a compound produced by salifying ambroxol with theophylline-7 -acetic acid. After acebrophylline administration, the salt splits into these two components which feature a peculiar pharmacokinetic behavior, an adequate ambroxol and a low theophylline-7-acetic acid serum levels. The purpose of the present study was to evaluate the bioequivalence of two acebrophylline capsules, Surfolase (Hyundai Pharm. lnd. Co., Ltd.) and Burophil (Kuhnil Pharm. Co., Ltd.), according to the guidelines of the Korea Food and Drug Administration (KFDA). The release of ambroxol from the two acebrophylline formulations in vitro was tested using KP VIII Apparatus II method with various dissolution media (pH 1.2, 4.0, 6.8 buffer solution and water). Twenty eight healthy male subjects, $23.25{\pm}1.43$ years in age and $64.82{\pm}6.77$ kg in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After two capsules containing 100 mg as acebrophylline were orally administered, blood was taken at predetermined time intervals and the concentrations of ambroxol in serum were determined using HPLC with electrochemical detector (ECD). The dissolution profiles of two formulations were similar at all dissolution media. In addition, the pharmacokinetic parameters such as $AUC_t$, $C_{max}$ and $T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t$, $C_{max}$ and untransformed $T_{max}$. The results showed that the differences between two formulations based on the reference drug Surfolase, were -1.64, -3.33 and -0.92% for $AUC_t$, $C_{max}$ and $T_{max}$, respectively. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log 0.8 to log 1.25 $(e.g., \;log\;0.93{\sim}log\;1.05\;and\;log\;0.88{\sim}log\;1.05$ for $AUC_t$, and $C_{max}$, respectively). Thus, the criteria of the KFDA bioequivalence guideline were satisfied, indicating Burophil capsule was bioequivalent to Surfolase capsule.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.12
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• pp.6973-6979
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• 2014

To mitigate global warming and climate change, many countries are investing massively on the development of CCS technology, which is assumed to be the key technology to reduce $CO_2$ emissions. CCS technology is comprised of the capture, transport, and storage processes. During the capture process, impurities other than $CO_2$ are inevitably flowed into the $CO_2$ stream. In the present study, corrosion characteristics of a phosphate coated tube for $CO_2$ transportation was investigated with a $CO_2$ stream composed of $CO_2$, $H_2O$, $SO_2$, and $NO_2$. The test specimen was a phosphate coated steel tube, which was filled with $CO_2$ stream with the impurities mentioned above. SEM-EDS analysis is conducted to investigate the corrosion behavior. The results showed that although the H2O concentration did not exceed the solubility limit, corrosion occurred in the specimen, which has an inflow of $SO_2$ or $NO_2$. This suggests that the $SO_2$, $NO_2$ and $H_2O$ concentration should be strictly controlled. These results suggest that the $SO_2$ and $NO_2$ concentration should be controlled below 175ppm and 65ppm, respectively.

• Korean Journal of Psychosomatic Medicine
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• v.14 no.1
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• pp.53-61
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• 2006

Objectives: This study was designed to evaluate difference of the alexithymia between panic patients and normal controls by examination of the relationships between different components of the alexithymia construct and level of anxiety and depression in panic patients and normal controls. Methods The subjects were 167 patients who met DSM-IV criteria for panic disorder and 110 normal controls. They drew up symptom checklists and self-rating scales, and were measured by Anxiety Disorders Interview Schedule-Panic attack & Agoraphobia(ADIS-P & A), Korean version of Toronto Alexithymia Scale (TAS-20K), Spielberger State-Trait Anxiety Inventory-State & Trait (STAI-S & T), Beck Depression Inventory (BDI), and Revised Anxiety Sensitivity Index (ASI-R). For statistical analysis, we performed t-test to compare the sociodemographic characteristics and the scores of self reported scales between panic patients and normal controls. Pearson correlation was performed between TAS-20K and it's subfactors, STAI-S & T, ASI-R and BDI in panic patients and normal controls. And stepwise multiple regression analysis was preformed to explain results of correlation analysis for alexithymia. Results: The panic patients reported more significant alexithymic (p<0.001), more difficulty identifying feeling (p<0.001) and describing feeling (p=0.001) than normal controls. Futhermore, panic patients were more significant anxious, sensitive to anxious feeling and depressive than normal controls. Moreover, the alexithymia of panic patients was explained by trait-anxiety $({\Delta}R^2=0.255)$ and anxiety sensitivity $({\Delta}R^2=0.062)$, that of normal controls was predicted by depression $({\Delta}R^2=0.144)$ and anxiety sensitivity $({\Delta}R^2=0.033)$ Conclusion: The panic patients reported more anxious and sensitive to anxious feeling, and these symptoms predict alexithymia in panic patients. However, the alexithymia of normal controls was explained by depression more than anxiety sensitivity, and such a result isn't consistent with previous studies and this may be mainly due to difference of the homogeneity in object of the studies.

• Journal of dental hygiene science
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• v.14 no.2
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• pp.158-166
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• 2014

This study is trying to grasp the stress of the male high school students and the correlation between the stress according to the oral health important cognitive and self-rated oral health status and number of brushing, emphasizing the need for the education of oral health important, providing the basic data in order to accomplish correctly until the enhance of oral health-related quality of the oral health correct behavior. From May to July 2013, a self administered survey was conducted by the selected by convenience sampling from subjects of two high school located in Chungcheongnam-do 1, 2 grade. The SPSS PASW Statistics 18.0 and Amos 5.0 program had been used for the statistical data analysis. The study results were as follow: 1) Among five areas of stress, the stress of school life was the highest as 2.11 points and the stress of home problem was the lowest as 1.51 points; 2) The significance analysis results between the five areas of stress according to the stress of latent variable and the oral health-related quality of life all showed the significant difference (p<0.001). 3) Oral health-related quality of life was higher as oral health important and self-rated oral health status positive. Furthermore oral health-related quality of life was higher as number of brushing increased; 4) Fit Measures test result of stress, academic level, and family economic level model all showed more than 0.9 in goodness of fit index (GFI), adjusted GFI, normed fit index and root mean square residual and root mean square error of approximation values is all estimated less than 0.1, so it showed good model. From this study, it can be concluded that there is the correlation between stress and oral health-related quality of life.

• Child Health Nursing Research
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• v.5 no.1
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• pp.38-47
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• 1999

This study is the study on health promoting behaviors of 6th grade students according to sex. The purpose of this study is to find the difference in the value of health in their lives among 6/sup th/ grade students according to sex, to examine the differences in practicing health promoting behaviors, and to determine the correlation between the practice of health promoting behaviors and the characteristics of these students. The subjects of this study were 177 6/sup th/ grade students who were randomly selected from two elementary schools in Taegu City. The tools used to measure health promoting behaviors were the measuring utility for practicing health promoting behaviors developed by Kyung-Suk Ki (1983) and the utility for the values of health in lives developed by Wallston, Maides and Wallston and translated by Gin Yoon (1989). The data collected were analyzed with t-test, Pearson correlation coefficient, and descriptive statistics using SPSS program. The results of the present study were as follows : 1) According to the results of the value placed in health in their lives, the number of students who placed health high in their lives was 69 boys (75%) and 64 girls (75.3%). 2) According to the results obtained from comparing the degree of practicing health promoting behaviors according to sex, in the field of personal hygiene and daily habits, the girls showed a higher degree of practice with 3.26±0.33 and the boys, 3.05±0.45(t=-3.484, p=0.001) : and in the field of contagious diseases, the girls scored significantly higher with 3.40±0.39 than the boys with 2.99±0.54(t=-2.363, p=0.019). In the filed of preventing accidents, the girls showed a meaning high significant result with 3.16±0.46 than the boys with 2.99±0.54(t=-2.362, p=0.019). When the results from the total questions in the field of health promoting behaviors were compared, the girls showed a meaningfully high correlation with 3.19±0.28 than the boys with 3.07±0.36(t=-2.601, p=0.010). Thus, the results showed that the girls, compares with the boys, practice more behaviors of personal hygiene & daily habits, prevention of communicable diseases, and prevention of accidents. 3) According to the results of the relationship between the subjects’ characteristics and their health promoting behaviors according to set in the case of the boys, they showed a meaningful positive correlation with health promoting behaviors and the current status of health (r=0.266, p=0.005). Thus, for the boys, as their health status was better, the more health promoting behaviors they showed. In the case of the girls, the meaningful variables had a correlation with the health promoting behaviors were the number of extra-curricula activities(r=0.182, p=0.047) and the birth order(r=-0.192, p=0. 024). In overall regardless of sex, the health status (r=0.188, p=0.006) and birth order(r=-0.149, p=0.024) showed a meaningful correlation with practicing health promoting behaviors. With the above results, we suggest the following proposals. 1) In elementary children of lower and upper classmen as applied with the current school age, developing a utility to measure health promoting behaviors is needed since the physical, emotional and intellectual development of these children exist. 2) According to the results of this study, developing a program for health promotion is needed in 6/sup th/ grade students.

• Journal of Korean Academy of Nursing
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• v.8 no.2
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• pp.89-102
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• 1978

Owing to the development of modern science, prolonging man's life, the sudden increase of population and betterment of the standard of living has increased health needs. In order to fulfill these health needs, more active plans for developing health should be made. Health education is one of the methods at hand that can improve the health behavior of the community and the individual through the contact of individuals with their groups. Proper understanding of the characteristics of the sampled group and participation of individuals within the community for the development of their health plan are needed for efficient health education. This study was attempted for the purpose of presenting some data helpful for pre-paring the fundamentals of a health education plan that can improve personal health maintenance practice of a community through efficient health education by investigating the relationship between the response of subjects to personal health maintenance practice and selected decisive factors in personal health maintenance practice. The subjects for this study were a systematic sample of 120 housewives selected from 600 housewives from B Zone Apt. Younhi-3-Dong in Seoul. Data was collected for 4 days from May 16th to May 19th, 1578 through personal interviews with questionnaires by well trained interviewers. Percentage, t-test and stepwise multiple regression analysis by use of EDPS were employed for statistical analysis. Results of this study can be summarized : 1. General characteristics of subjects Subjects over 20 and below 40 years of age formed 62.5% of the toed and the rest were subjects of 40 years and upward. 76.7% of the subjects have less than 4 children. 51.3% of the subjects had completed at least the senior high school course. 2. The response of subjects to personal health maintenance practice. Ratios of personal health maintenance practice to the maximum score for each category are as follows; 84.1% in the category of population and family planning, which was the highest ratio; 82.4% in the prevention of accidents; 68.0% in control of communicable disease; 67.8% in personal health care and habits of daily life, 64.3% in mental health and 52.5% in control of parasites, which was the lowest. 3. The response of subjects to selected decisive factors. in personal health maintenance practice. The arithmetic mean of the score for each decisive factor was as follows: the mutual relation between family members marked 18.33, which is under 73,3% of the maximum score; the degree of interest in health marked 34.48, 70.0% of the maximum score: the degree of utilization and demand for health care facilities marked 25.79 or 64.5% of the maximum score and health maintenance of the family marked 11.58, 43.6% of the maximum score. 4. The relationship between personal health maintenance practice and general characteristics of subjects. 1) There was a significant difference in the numbers of children. (t = 1.83, d.f. =117, p< 0.1) 2) There was a significant difference in the contact rates with mass-media, (t = 5.02, d.f. = 118, p< 0,05) 5. The multiple correlation between personal health maintenance practice and their selected decisive factors. 1) The factor“the degree of interest in health”could account for personal health maintenance practice in 43.6% of the sample. (R = 0.6602, R²= 0,4359, F = 91.1678, p< 0.001) 2) When the factor,“health maintenance of family”is added to this, it accounts for 51.2% of personal health maintenance practice. (R = 0.7158, R²= 0.5124, F = 61.4653, p< 0.001) 3) When the factor,“mutual relations between family members”is also included, it accounts for 53.7% of personal health maintenance practice. (R = 0.7324, R²= 0.5365, F = 44.7509, p< 0.001) 4) When the factor, “the degree of utilization and demand for health care facilities”is included, it accounts for 55.1% of personal health maintenance practice. (R = 0.7421, R²= 0.5507, F = 35.2430, p< 0.001).