• Journal of Energy Engineering
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• v.17 no.3
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• pp.167-174
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• 2008

Line source model is commonly used in analyzing the data obtained from thermal response test to estimate the effective soil formation thermal conductivity. In the application of line source model some part of initial data must be ignored in order to achieve more accurate result. The period of time for this initial data is called initial ignoring time(IIT) in this paper. However there has been no definite rule in determining this initial ignoring time. Therefore line source model requires experienced analyzer to select the useful data, which is somewhat subjective. One method often suggested is the calculation of IIT with non dimensional time $\tau=5$. However, this is a very theoretical result derived from a system of perfect line source model, which is somewhat different from the real system. A new method to determine IIT is presented in this study. This method requires error estimation first and IIT can be decided from the results of error estimation. This method is applied in the analysis of field test data and shows better result than the one obtained from the method using non dimensional time mentioned above as shown in Table 2.

• Journal of dental hygiene science
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• v.13 no.2
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• pp.142-150
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• 2013

The aim of this study was to analyze the factors related to self-reported halitosis. This study performed a questionnaire survey, targeting at 450 adults who lived in Seoul and Gyeonggi area. Main results of this study were as followings. Relationships between socio-demographic characteristics and halitosis showed no significant difference. Relationships between subjective oral health and halitosis, the groups that were treated dental prosthesis, aware of periodontal disease and dry mouth symptoms reported more halitosis (p<0.05). The group that brushed teeth less than twice a day, did not brush teeth after having a snack, and had frequent sweet treat reported more halitosis (p<0.05). The group that more experienced limitation, discomfort, discomfort reported more halitosis (p<0.05). Based on the results derived as above, the self-reported halitosis was shown to be related to periodontal disease, dry mouth, oral hygiene care and quality of life. Therefore, it is considered that preventing periodontal disease and oral dryness as well as reinforcing the oral hygiene care will contribute to prevention of halitosis and enhancement of quality of life.

• Archives of design research
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• v.20 no.3 s.71
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• pp.97-106
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• 2007

This study examines whether the reinforcement theory could be effectively applied to teaching assistant robots between a robot and a student in the same way as it is applied to teaching methods between a teacher and a student. Participants interacted with a teaching assistant robot in a 3 (types of robots: positive reinforcement vs. negative reinforcement vs. both reinforcements) by 2 (types of participants: honor students vs. backward students), within-subject experiment. Three different types of robots, such as 'Ching-chan-ee' which gives 'positive reinforcement', 'Um-bul-ee' which gives 'negative reinforcement', and 'Sang-bul-ee' which gives both 'positive and negative reinforcement' were designed based on the reinforcement theory and the token reinforcement system. Subjective impressions and preferences were measured according to the types of robots and the types of participants. Participants preferred the positive reinforcement robot most, and the negative reinforcement robot least. Regarding the number of stimulus, in case of the negative reinforcement robot for honor students, the less the stimulus is, the more positive the impressions toward the robot are. The findings demonstrate that the reinforcement interaction is important and effective factor which determines children's preferences and impressions for teaching assistant robots. The results of this study can be implicated as an effective guideline to interaction design of teaching assistant robots.

• Korean Journal of Construction Engineering and Management
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• v.8 no.1 s.35
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• pp.66-77
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• 2007

With the electricity industry structure reformation of the government in April, 2001, Korea Power Electric Corporation was divided in to Korea water power nuclear power and 5 thermal power plant. After, various delivery method is introduced and applied for active profit creation according to the competition between each development companies for the public company privatization. However, the current situation does not satisfy the project participant by selecting the delivery method without reflecting the business goal and project characteristics of power plant construction business. The objective of this study is to research the influencing factors that should be considered to select the delivery method in thermal power construction business and develop a standard of selection of appropriate delivery method through questionnaire and interviews to establish a model to select the delivery method that fits the business goal of the subject of delivery. In the future, if the delivery method selection model suggested in this study is applied, it is expected to select the appropriate delivery method of power plant construction business by effectively reflecting the business goal, characteristics and demand of the delivery subject, and characteristics of the construction business apart from the existing customary practices that decided the delivery method dependent on the subjective and experience based judgement.

• Journal of the Korea Society of Computer and Information
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• v.25 no.7
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• pp.17-25
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• 2020

Based on the successful use of chatbot technology, this study examined what business values each company is creating. The chatbot service contributes to improving the productivity of the company by helping to answer or respond to the questions of employees inside the company or customers. And in the field of education, Instead of instructor, AI technology responds the questions and feedback of the students to reduce the work of the instructor. In the field of commerce, offline stores provide convenient and new purchasing experiences to customers by providing product purchasing services through artificial intelligence speakers and personalization service. Although chatbot service is creating business value in some business cases, it is still limited to the process of a specific company, and the spread rate is still slowing because the service scope, convenience, and usefulness are not greater than expected. Therefore, some chatbot development service providers is providing an integrated development platform to improve usability, Chatbots have the features and advantages of providing convenience instead of answering human questions. However, there is a disadvantage that the level of communication can be lowered by reducing various human subjective views and giving mainly objective answers. Through this study, we will discuss the characteristics, advantages and disadvantages of chatbot services by comparing them.

• Tuberculosis and Respiratory Diseases
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• v.59 no.1
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• pp.62-68
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• 2005

Background : The clinical results of a Natural stent in patients with a benign tracheobronchial stenosis were examined by comparing the clinical outcomes and complications of those patients who underwent Dumon and Natural stenting in the management of benign airway stenosis. Methods : The medical records of 94 patients (39 Dumon and 55 Natural stent) with a benign tracheobronchial stenosis were reviewed and analyzed. Results : Post-tuberculous stenosis was the leading indication for airway stenting (74%), which was followed by post-intubation stenosis (21%). After intervention, the dyspnea had improved among those patients who underwent Dumon (90%) and Natural (86%) stenting. After stabilizing the dyspnea, the stent could be successfully removed in half of the patients who underwent both Dumon (54%) and Natural (49%) stenting. During the 42 month follow-up period, the complication rate was similar in those patients who underwent Dumon and Natural stenting: migration (46% vs 53%), granulation tissue formation (36% vs 49%), mucostasis (21% vs 16%) and restenosis (51% vs 36%). Conclusion : The clinical results of Natural airway stent was similar to those of Dumon stent in the management of benign tracheobronchial stenosis.

• Journal of Korean Home Economics Education Association
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• v.16 no.3
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• pp.115-129
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• 2004

We investigated the prevalence of eating disorder risk group and its relationship with Physique status and eating behavior among high school students in Daejeon. In May - June 2002, 350 students were sampled from 6 high schools in Daejeon by multi-stage cluster sampling and assessed with self-completing questionnaires. We used the Korean version of Eating Attitude test(EAT-26) to screen eating disorder risk group. and other instruments to screen physique status and eating behavior. The response rate was 91%(total 320) and numbers of female students were 167(52.2%) and male students were 153(47.8%). Average age was 16.0${\pm}$0.35 years, and average body-mass index(BMI) and PIBW(Percent Ideal Body Weight) were 20.9${\pm}$3.3 Kg/m2 and 102${\pm}$4.2% in male students, 20.2${\pm}$3.7 Kg/m2 and 98${\pm}$7.2% in female students(p<0.0001). Over 50% of the subjects were dissatisfied with their body shape; the degree of dissatisfaction with body shape was higher in those who believed themselves to be fat. Mean score of EAT-26 was higher in female students (10.78${\pm}$7.36) than male students(6.07${\pm}$4.39)(p<0.0001). The prevalence of high risk eating disorder group was 2.6% in male students, 11.4% in female students(p<0.0001). Eating behavior was better in female students than male(p<0.0001). Eating behavior was significantly higher in eating disorder risk group in both sex. Therefore eating disorder symptomatology was highly prevalent among high school students in Daejeon. And this symptomatology has a more close relationship with physique status and eating behavior in female students.

• Journal of Dental Rehabilitation and Applied Science
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• v.32 no.2
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• pp.109-116
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• 2016

Purpose: The aim of this study was to evaluate correlations between denture satisfaction and various factors related to patients' and wearing dentures. Materials and Methods: Total 43 edentulous patients were recalled and they were wearing complete dentures fabricated more than one year ago. For patients' subjective assessment, the questionnaire based on the various literatures was developed and applied to patients for data acquisition. In addition, correlations were evaluated between subjective assessment and denture satisfaction score. For statistical analysis, Spearman correlation coefficient, multiple regression analysis, Mann-whitney U test and Kruskal-Wallis test were used to found out what the most considerable factors to denture satisfaction score (P < 0.05). Results: Denture satisfaction score of maxilla was higher than mandible (P < 0.05). In functional aspects, maxillary denture were received a favorable evaluation. Especially fit and pain causing were highly correlated to satisfaction. Gender, age, using period, visiting times after manufacturing denture were unrelated to satisfaction. But previous experience was related to denture satisfaction. Conclusion: Denture satisfaction was determined by a combination of various factors related to patients.

• Journal of Korea Water Resources Association
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• v.33 no.3
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• pp.315-330
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• 2000

The GIUH (Geomorphologic Instantaneous Unit Hydrograph) is to be applied to the ungauged or insufficiently gauged basins. For tIris purpose, an accurate estimation of the charactenstlc velocity is one very important part, but any proper method for this has not been developed yet. In case that we have enough rainfall and runoff clata, the estimation of the characteristic velocity may be an easy job, but it is out of the purpose of the GIUH. Remindmg that the purpose of GIUH the characterisbc veloclty should be estimated based on the geomorpholog1c analysis and also be snnple for easy apphcation. In tIris research analysis cmd application of the GruH was given to several sub-basins in Wi-stream river basin, Gono, Donggok and Hyoryung. After deriving the characteristic velocity througn a optimizatlOn process with real data, it is compared w1th several velOCIties der1ved from geOlnoI1Jhoclimatic instantaneous unit hydrograph theory and several other concentration time formulae. The estimated charactenstic velocities using Kerby, Kim, KInematic Wave, and Brasby- Williams formulae found to g1ve the appropriate results. Hmvever, as the Kerby, and the Kinematic Wave require user's decision of the IvIanning's n value, the K1m and the Braby-Williams seem to be more applicable and recommended as characteristic velocity formula.

• The Journal of the Korea Contents Association
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• v.12 no.11
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• pp.258-266
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• 2012

This study was conducted to investigate the differences between smokers and non-smokers' oral hygiene and college students' smoking awareness. The survey was carried out based on the 260 college students enrolled in four-year universities located in Kyungbuk, Daegu, Gangwon-do. Collected date used the SPSS 17.0 to perform the frequency and cross-analysis. 1. The daily smoking amounts of less than half pack and the smoking duration of more than 1 year and less than 3 years were to be the highest. The initiation of smoking was triggered by the curiosity and the proximal social environment. The reason of smoking was to relieve stress and habitual smoking respectively. 2. There was a significant difference between smokers and non-smokers' tooth brushing time, regular dentist visit, recent dental admission, the purpose of dental visits, scaling and oral health education. 3. There was a significant difference between smokers and non-smokers' awareness of oral hygiene in the subjective oral hygiene status. 4. There was a significant difference between smokers and non-smokers' awareness towards the impact of second-hand, after meal and one or two cigarette smoking. Based on the above results, smokers lack the awareness of smoking and oral hygiene compared to non-smokers. Therefore, the activation and the development of programs for the smoking and oral hygiene education targeting college students are considered to be necessary.