• The Journal of Korean Society for Radiation Therapy
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• v.21 no.2
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• pp.83-88
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• 2009

Purpose: Cone beam computed tomography (CBCT) using an on board imager (OBI) can check the movement and setup error in patient position and target volume by comparing with the image of computer simulation treatment in real.time during patient treatment. Thus, this study purposed to check the change and movement of patient position and target volume using CBCT in IMRT and calculate difference from the treatment plan, and then to correct the position using an automated match system and to test the accuracy of position correction using an electronic portal imaging device (EPID) and examine the usefulness of CBCT in IMRT and the accuracy of the automatic match system. Materials and Methods: The subjects of this study were 3 head and neck patients and 1 pelvis patient sampled from IMRT patients treated in our hospital. In order to investigate the movement of treatment position and resultant displacement of irradiated volume, we took CBCT using OBI mounted on the linear accelerator. Before each IMRT treatment, we took CBCT and checked difference from the treatment plan by coordinate by comparing it with the image of CT simulation. Then, we made correction through the automatic match system of 3D/3D match to match the treatment plan, and verified and evaluated using electronic portal imaging device. Results: When CBCT was compared with the image of CT simulation before treatment, the average difference by coordinate in the head and neck was 0.99 mm vertically, 1.14 mm longitudinally, 4.91 mm laterally, and 1.07o in the rotational direction, showing somewhat insignificant differences by part. In testing after correction, when the image from the electronic portal imaging device was compared with DRR image, it was found that correction had been made accurately with error less than 0.5 mm. Conclusion: By comparing a CBCT image before treatment with a 3D image reconstructed into a volume instead of a 2D image for the patient's setup error and change in the position of the organs and the target, we could measure and correct the change of position and target volume and treat more accurately, and could calculate and compare the errors. The results of this study show that CBCT was useful to deliver accurate treatment according to the treatment plan and to increase the reproducibility of repeated treatment, and satisfactory results were obtained. Accuracy enhanced through CBCT is highly required in IMRT, in which the shape of the target volume is complex and the change of dose distribution is radical. In addition, further research is required on the criteria for match focus by treatment site and treatment purpose.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.1
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• pp.1-10
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• 2012

Digital Forecast of the Korea Meteorological Administration (KMA) represents 5 km gridded weather forecast over the Korean Peninsula and the surrounding oceanic regions in Korean territory. Digital Forecast provides 12 weather forecast elements such as three-hour interval temperature, sky condition, wind direction, wind speed, relative humidity, wave height, probability of precipitation, 12 hour accumulated rain and snow, as well as daily minimum and maximum temperatures. These forecast elements are updated every three-hour for the next 48 hours regularly. The objective of this study was to construct Forest Fire Danger Rating Systems on the Korean Peninsula (FFDRS_KORP) based on the daily weather index (DWI) and to improve the accuracy using the digital forecast data. We produced the thematic maps of temperature, humidity, and wind speed over the Korean Peninsula to analyze DWI. To calculate DWI of the Korean Peninsula it was applied forest fire occurrence probability model by logistic regression analysis, i.e. $[1+{\exp}\{-(2.494+(0.004{\times}T_{max})-(0.008{\times}EF))\}]^{-1}$. The result of verification test among the real-time observatory data, digital forecast and RDAPS data showed that predicting values of the digital forecast advanced more than those of RDAPS data. The results of the comparison with the average forest fire danger rating index (sampled at 233 administrative districts) and those with the digital weather showed higher relative accuracy than those with the RDAPS data. The coefficient of determination of forest fire danger rating was shown as $R^2$=0.854. There was a difference of 0.5 between the national mean fire danger rating index (70) with the application of the real-time observatory data and that with the digital forecast (70.5).

• The Journal of the Korea Contents Association
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• v.14 no.6
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• pp.108-118
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• 2014

The purpose of this study is to develop a relationship of measuring method for the social security network and verify its validity and reliability and apply it to investigate the due to security life satisfaction. This study is based by setting general residents of Seoul in 2013 and using the stratified cluster random sampling method to analyze a total amount of 203 examples. The measuring methods for the social security network was developed through document research, conceptual definition and drafting the survey, experts' conference, preliminary inspection and original examination, verification of the validity and reliability of the survey. An experts' conference took pace to verify the validity of the survey, and 6 factors were extracted through exploratory factor analysis crime prevention design, street CCTV facilities, volunteer neighborhood patrol, local government security education, police public peace service, private security service. The conclusion are the following. Collected data was analyzed based on the aim of this study using SPSSWIN 18.0, and practice frequency analysis, F test, factor analysis, reliability analysis, correlation analysis, multiple regression analysis. First, the validity of the social security network measurement is very high. Thus, the factors constituting the social security network were found to be crime prevention design, street CCTV facilities, volunteer neighborhood patrol, local government security education, police public peace services, and private security services, and the crime prevention design factor was found to be most explanatory. Second, the reliability of the social security network measurement is very high. Thus, the correlation between the questions and the sector, the questions and the social security net was very high, and the internal consistency showed a Cronbach's${\alpha}$ value of over 0.865. Third, the establishment of a social security network had the biggest effect on people in their forties. Thus, when the crime prevention design, street CCTV facilities, local government security education, police public peace services are systematically established, the social anxiety of citizens was reduced.

• Journal of Venture Innovation
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• v.3 no.1
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• pp.1-26
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• 2020

The purpose of this study is to explore the factors affecting rural experience by applying the unified push-pull-mooring model. The theoretical model is an unified PPM model that introduces new variables based on PPM. The pull factor of the newly introduced variables were reconstructed based on the Schmitt's Experience model and ServQual model. The hypothesis is set as follows. The push factor will have a negative effect on experience satisfaction and the pull factor(experience attributes, service quality)will have a positive effect on experience satisfaction. Also, mooring factors will have a negative effect on experience satisfaction. The research model of this study was tested by structural equation model based on 314 effective questionnaire data. Service quality had a positive effect on experience satisfaction. Mooring factors have a negative effect on experience satisfaction. Push factor and experience attributes factor were analyzed to have a no significance effect on experience satisfaction. These results theoretically test that the mooring factors also have an important effect on the experience satisfaction in the rural experience. Based on the Schmitt's Experience model and ServQual model introduced as a pull factor, the proposed unified PPM model proved to be a useful analysis framework. In practice, it was able to provide implications on what factors should be strategically and marketingly focused to activate the 6th industry experience.This study examined the impact of start-up education and mentoring on the intentions of business start-up, and verified through empirical analysis whether self-efficacy and resilience were mediated between them. The study surveyed 178 people in their 20s to 50s. The result analysis used the IBM SPSS Statistics 21.0 Statistical Package Program. The analysis performed a regression analysis for factor analysis, correlation analysis, and hypothesis verification. Empirical Research Results. First, it was confirmed that start-up education and mentoring affect on the intentions of business start-up. Second, study shows self-efficacy and resilience has an affect on the intentions of business start-up. Third, start-up education and mentoring affect on self-efficacy and resilience. Fourth, self-efficacy and resilience have been proven to be mediated when entrepreneurship education and mentoring affect on the intentions of business start-up. The results of the research proved that start-up education and mentoring provides and acts as a major role in improving the entrepreneurs' willingness when preparing a start-up. Furthermore, the study also shows the importance of start-up education and mentoring as a proactive variable to promote their will to start-up business. In addition, it was confirmed that the self-efficacy investigated in the preceding study translated into the will to start a business. It was particularly meaningful in that it tested the role of resilience, which was mainly studied in new variables, education and psychology.

• Journal of Technologic Dentistry
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• v.31 no.3
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• pp.35-45
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• 2009

This survey study was conducted on dental technician school students in April 2008 to investigate the effects of smoking on oral health. 110 male and 39 female students were surveyed and cross analysis was performed to examine the relationship between oral health status and smoking-related and oral health maintenance characteristics of smoking and non-smoking group. T-test and one-way ANAVA was used to analyze the average difference verification of two independent samples(smoking group and non-smoking group) and followings are the results. In general characteristics, 74 male students(74.7%) and 25 female(25.3%) students smoked and the percentage of male students were higher in smoking group. Regarding class grade, 2nd-year students(37 students, 37.4%) and 1st-year students(18 students, 36.0%) took the highest percentage of smoking and non-smoking group, respectively. Concerning the experience of drinking, smoking group consumed more alcoholic beverages(94 students, 94.9%) With respect to the frequency of between-meal consumption, respondents who eat between-meal once or twice smoked more. Respecting preferences of sweet food, respondents who enjoyed sweet food smoked more. Concerning smoking characteristics, many of smoking group had been smoked fo a long time(two to five years) and it was worrisome. About the amounts of smoking, 50 respondents(52.6%) of smoking group smoked 20 cigarettes a day with the highest proportion. With regard to the awareness of harmfulness, 70 respondents(70.7%) considered smoking as very harmful and showed that smoking group were aware of its harmfulness but it was habitualized. Respecting smokers in family members, father was more common as smokers(58 respondents, 58.6%) in family and showed that the influence of father. Main reasons of poor periodontal health were alchoholic consumption, smoking, and oral parafunctional habit(57 respondents, 56.7%) in smoking group and neglect of oral hygiene(21 respondents, 42.0%) in non-smoking group. With regard to the scaling, 80 respondents of smoking group(80.8%) didn't received scaling and showed that more oral health education was required. Regarding the periodontal status, non-smoking group was $1.26{\pm}0.44$, respondents who received scaling was $1.43{\pm}0.50$, respondents who regularly floss was $1.50{\pm}0.52$, respondents who brush more than three times a day was $1.38{\pm}0.49$ and had better periodontal health. Bleeding during tooth brushing was more frequent in smoking group ($1.51{\pm}0.70$). Regarding mouth order, non-smoking group was $2.34{\pm}0.62$, after scaling was $2.02{\pm}0.76$, patients who regularly floss was $1.50{\pm}0.52$, patients who brush more than three times a day was $1.81{\pm}0.87$. Concerning the experience of dental caries treatment, smoking group was $1.20{\pm}0.40$, patients who do not floss was $1.30{\pm}0.46$, patients who brush once a day was $1.29{\pm}0.45$. With regard to dental prosthesis, non-smoking group was $3.78{\pm}1.62$, patients who received scaling was $1.43{\pm}0.50$, patients who regularly floss was $1.40{\pm}0.51$, patients who brush more than three times a day was $1.24{\pm}0.43$. From these results, oral health education and smoking has correlation and more oral health education needs to be carried out to educate students with non-health related majors about harmfulness of smoking on oral health. Also more study are required.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.4
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• pp.488-498
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• 2007

The purposes of this study were to: a) provide evidences concerning the effects of emotional leadership b) examine the impacts of emotional leadership on employee-related variables, 'job satisfaction', 'organizational commitment', 'organizational performance' and 'turnover intention', and c) identify a conceptual framework underlying emotional leadership. A survey was conducted from August 23 to November 3, 2005 to collect data from mid-level managers in food service company headquarters (N=219). Statistical analyses were completed using SPSS Win (12.0) for descriptive, reliability, factor and correlation analyses and AMOS (5.0) for confirmatory factor analysis and structural equation modeling. The main results of this study were as follows. First, the managers gave the highest point to their leaders in the emotional leadership competence 'organizational awareness : reading the currents, decision networks, and politics at the organizational level' and gave the lowest point in the emotional leadership competence 'influence: wielding effective tactics for persuasion'. Second, the means of job satisfaction was above the midpoint (3 points). Employees' job satisfaction with 'coworkers' was relatively high. However, the extents of satisfaction with 'payroll' 'promotion', and 'work environment' were relatively low. Third, the organizational commitment was above the midpoint (3 points). In the organizational commitment, 'loyalty' factor was higher than 'commitment' factor. Fourth, the means of organizational performance was above the midpoint. The highest organizational performance variable was 'internal efficiency; trying to reduce cost' and the lowest organizational performance variable was 'internal fairness ; equitable treatment and all are treated with respect with no regard to status and grade'. Fifth, most respondents intended on 'thinking of quitting ; towards turnover process'. Sixth, the test of hypothesis using structural equation modeling found that emotional leadership produced p[Isitive effects on job attitude and job performance. Emotional leadership enhanced job satisfaction and organizational commitment, and in turn, employees' attitude positive effects on organizational performance; emotional leadership also had a direct impact on organizational performance

• Journal of the Korean Geotechnical Society
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• v.19 no.6
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• pp.71-84
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• 2003

The metallic shell of soil-steel structures are so weak in bending moment that it should sustain the applied load by the interaction of the backfill soil around the structures. The shell can be subjected to excessive bending moment during side backfilling or under live-load when the soil cover is less than the minimum value. The current design code specifies the allowable deformation and Duncan(1979) and McGrath et al.(2001) suggested the strength analysis methods to limit the moments by the plastic capacity of the shell. However, the allowable deformation is an empirically determined value and the strength analysis methods are based on the results of FE analysis, hence the experimental verification is necessary. In this study, the full-scale tests were conducted on the high-profile arch to investigate its behaviors during backfilling and under static live-loads. Based on the measurements, the allowable deformation of the tested structure could be estimated to be 1.45% of rise, which is smaller than the specified allowable deformation. The comparison between the measurements and the results of two strength analyses indicate that Duncan underestimates the earth-load moment and overestimates the live-load moment, while McGrath et al. predicts both values close to the actual values. However, as the predicted factors of safeties using two methods coincide with the actual factor of safety, it can be concluded that both methods can predict the structural stability under live-loads adequately when the cover is less than the minimum.

• Science of Emotion and Sensibility
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• v.13 no.1
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• pp.1-10
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• 2010

This study is about what process and methodology could make UI designer be able to achieve the interface which considers user's mental model through implementing corporate line-up model, when people design an interface between product of multi-function printer and user. The most important concern of UI designers who are dealing with an interface between product and user is how they can make product system image match user's mental model so that users can utilize products without any confusion and discomfort. If concept model which designers bring up and mental model which users expect and recognize could be of one accord, then users can feel ease of use toward products. The understanding and observation for user behavior and use pattern is prerequisite to develop user-centered interface between product and user. However, UI designers do design interface from their own perspective and assumption in many business areas, and users do not react as designers assumed and intended in many cases or examples. This study is to find inappropriate system images against users' mental model on basic function of multi-function printer, and the relationship of system image and user's mental model is diagramed to build up a hypothesis. The hypothesis from this study is validated through evaluation of domestic and international users. In addition, two suggestions to improve usability problems revealed from user test are proposed. The optimal solution is designed based on the result of user evaluation and consideration of many user environments, and then it is implemented to line-up product. In conclusion, this study considers how UI designers can create system image which is close to user's mental model.

• Journal of Korean Society of Transportation
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• v.22 no.3 s.74
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• pp.145-157
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• 2004

The cycle length design model of the Korean traffic responsive signal control systems is devised to vary a cycle length as a response to changes in traffic demand in real time by utilizing parameters specified by a system operator and such field information as degrees of saturation of through phases. Since no explicit guideline is provided to a system operator, the system tends to include ambiguity in terms of the system optimization. In addition, the cycle lengths produced by the existing model have yet been verified if they are comparable to the ones minimizing delay. This paper presents the studies conducted (1) to find shortcomings embedded in the existing model by comparing the cycle lengths produced by the model against the ones minimizing delay and (2) to propose a new direction to design a cycle length minimizing delay and excluding such operator oriented parameters. It was found from the study that the cycle lengths from the existing model fail to minimize delay and promote intersection operational conditions to be unsatisfied when traffic volume is low, due to the feature of the changed target operational volume-to-capacity ratio embedded in the model. The 64 different neural network based cycle length design models were developed based on simulation data surrogating field data. The CORSIM optimal cycle lengths minimizing delay were found through the COST software developed for the study. COST searches for the CORSIM optimal cycle length minimizing delay with a heuristic searching method, a hybrid genetic algorithm. Among 64 models, the best one producing cycle lengths close enough to the optimal was selected through statistical tests. It was found from the verification test that the best model designs a cycle length as similar pattern to the ones minimizing delay. The cycle lengths from the proposed model are comparable to the ones from TRANSYT-7F.

• Analytical Science and Technology
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• v.25 no.3
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• pp.178-189
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• 2012

As phthalates classified as toxic to reproduction category 2 and endocrine disrupting chemicals were more strictly regulated as Substances of Very High Concern (SVHC) for authorization in under EU REACH and considered as priority substances in RoHS II, standardization of phthalate testing method is now being proposed in IEC 62321 of IEC TC 111 and the 2nd revision of KS M 1991 is also finished. In order to assist standardization activities related to phthalating testing, solvent extraction part of existing national standards were compared and verified. Recovery of DEHP (diethylhexyl phthalate) from PVC (polyvinyl chloride) by Soxhlet extraction increased in the order of methanol, toluene, dichloromethane and hexane from 46.9% to 95.3% as measured by GC-MS. Optimum extraction time was verified to be 6 hours using hexane. Recovery of DBP (dibutyl phthalate), BBP (butylbenzyl phthalate), and DEHP from different matrixes such as PVC, nitro cellulose, ABS (acrylonitrile butadiene styrene). and EPDM(ethylene propylene diene monomer) rubber were evaluated to be more than 90% up to 99%. The detection limits of phthalates in solvent extraction followed by GC-MS analysis were 0.08~0.3 ${\mu}g/mL$ in solution and 8~30 mg/Kg in polymeric samples. GC-MS analyses of phthalates were carried out using different solvent extraction based on the EN 14372, ASTM D 7083, Japanese test method (MHLW 0906-4) and KS M 1991, proving that equivalent recoveries ranging from 98%~99% were obtained. DBP and DEHP were detected in three consumer products such as a child toy, a power cable and manicure with the amount of 22~1,910 mg/kg.