• Journal of Korean society of Dental Hygiene
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• v.17 no.2
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• pp.181-191
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• 2017

Objectives: The objective of the study was to investigate the use of dental hygiene devices in Korean adolescents. Methods: The study subjects were 70,362 adolescents in 800 schools who completed the 2015 Korean Youth Risk Behavior Web-based survey. Dependent variables included usage of dental floss, interdental brushes and mouthwash solutions. Independent variables included demographic characteristics of the subjects, health state and behaviors, and oral health behaviors and experience of oral diseases. Results: The related factors of usage of dental hygiene devices included gender, where females showed higher usage (OR=1.10) compared to males, father and mother's level of education where usage was higher in above university graduates (OR=1.20, OR=1.14) compared to less than high school graduation, economic status where usage was higherin high and middle (OR=1.93, OR=1.26) compared to low, vigorous physical activity where usage was higher in those who responded yes (OR=1.35) compared to no, subjective weight recognition where usage was higher in normal (OR=1.07) compared to under weight, sleep time where usage was higher in enough (OR=1.12) compared to not enough, number of toothbrushing (day) where usage was higher in 2 times or over 3 times (OR=1.35, OR=1.75) compared to below 1, oral health education experience (OR=1.10), sealant experience (OR=1.17) and scaling experience (OR=1.45) where usage was higher in those who responded yes compared to no, school where usage was lower in high school (OR=0.64) compared to middle school, residential type where usage was lower in rural area (OR=0.74) compared to metropolitan area, living form where usage was lower in other (OR=0.77), compared to with family, smoking (OR=0.93), and alcohol drinking (OR=0.90) where usage was lower in those who engage in the activities compared to those who didn't, BMI where usage was lower in normal (OR=0.87) and over weight (OR=0.98) compared to under weight. Conclusions: To expand the use of dental hygiene devices in the adolescents, it is necessary to improve the continuing education program for need and motivation of dental hygiene device usage.

• Korean Journal of Environmental Agriculture
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• v.23 no.1
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• pp.1-6
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• 2004

The seeding sources and concentration of ammonia on anaerobic digestion were investigated by batch culture bioreactors. The sources of seeding on anaerobic digestion were from swine wastewater collection pit of a hog raising farm and from anaerobic digestion sludge of a municipal sewage treatment plant. The inhibition of ammonia on anaerobic microorganisms was initiated at ammonia concentration of $1,500\;mgNH_4-N/L$ and it's effect was increased by increased by increasing ammonia concentration up to $3,500\;mgNH_4-N/L$ regardless the sources of seeding as evidenced by decreases in COD removal efficiencies and biogas yields. The inhibition occurred to not only methanogens but also acidogens since the concentration of volatile fatty acids was maintained at 50 mg/L The COD removal efficiency and biogas yield were Maintained constantly while increasing ammonia concentration up to $3,500\;mgNH_4-N/L$ when swine wastewater collection pit was used as a seeding; however, those were decreased while increasing ammonia concentration when anaerobic digestion sludge was used as a seeding. The results indicate that the seeding acclimated to high concentrations of ammonia for long time was easy in adaptation to high ammonia concentration and less subjective to ammonia inhibitory effects.

• Journal of Korean Foot and Ankle Society
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• v.20 no.3
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• pp.126-130
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• 2016

Purpose: The aim of this study was to evaluate the result of extraarticular dorsal closing wedge osteotomy in Freiberg's disease. Materials and Methods: Between February 2012 and July 2014, total 10 patients who underwent dorsal closing wedge osteotomy and followed up more than 1 year were selected for inclusion. Average age was 16.3 years, and average follow-up period was 15.5 months. The diagnosis was made using magnetic resonance imaging of those with a limitation in walking or usual activity due to pain in the metatarsal head. During operation, we removed loose body, and synovectomy was done. Osteotomy at the metatarsal neck and fixation with Kirschner wire were performed. X-ray was taken to check shortening of 2nd metatarsal and bone union. Moreover, we checked the active range of motion of 2nd metatarsophalangeal joint before and after surgery. At the last follow-up, the shortening of metatarsal, American Orthopaedic Foot and Ankle Society (AOFAS) score, visual analogue scale (VAS), and patient's subjective satisfaction were evaluated. Results: According to the Smillie's stage, there were 3 cases of stage II, 4 cases of stage III, and 3 cases of stage IV. Average bone union time on the osteotomy site was 8 weeks. Average shortening of metatarsal was 2.53 mm. Average AOFAS score improved significantly from 56.9 to 82.8 points at final follow-up (p<0.05), and average VAS score also improved significantly from 6.4 to 1.4 points at final follow-up (p<0.05). Average active range of motion at metatarsophalangeal joint improved from $28.0^{\circ}$ preoperatively to $46.5^{\circ}$ at the final follow-up. Other complications, such as metatarsalgia and arthritis, were not found; however, there was 1 case of delayed union with no symptom. Conclusion: In Freiberg's disease, dorsal closing wedge osteotomy is recommended for the improvement of clinical symptoms and range of motion.

• Journal of Environmental Impact Assessment
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• v.25 no.2
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• pp.141-154
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• 2016

This study was conducted laying the focus on finding the mutual action between the substantial ecological value and economic system in the national land, and calculating the environmental carrying capacity and sustainability of the national land using the emergy synthesis. Particularly, this study pays attention watchfully to the reality that the analytic framework to analyze sustainability is not arranged well, as the concept of sustainable development considering environmental carrying capacity, which becomes a widely discussed topic today, is defined differently according to the subjective views of respective researchers, and the situation which needs in-depth evaluation on the interaction between nature and economy which becomes the fundamental of sustainable development. This study also aims at groping for correct direction for the national land development by calculating the environmental carrying capacity and index value which is appropriate to the national land and providing the framework for preparing the policy to induce the sustainable use and management of the national land. The concept of emergy synthesis which is used for the evaluation of environmental carrying capacity and sustainability in the national land, as in this case, can notify the information on current situation of the national land as well as explain how the national land transforms according to time pass (the role of information synthesis), and gives knowledge if the national land policies advances toward the direction of sustainable development (the role of policy evaluation and observation). Emergy synthesis also can take role for selecting best policy on the process of decision making on the exploitation of the national land (the role on the process of decision making).

• The Korean Journal of Applied Statistics
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• v.33 no.3
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• pp.321-334
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• 2020

The US Federal Reserve (Fed) has decided to cut interest rates. When we look at the expression of the FOMC statements at the time of policy change period we can understand that Fed has been communicating with markets through a change of word selection. However, there is a criticism that the method of analyzing the expression of the decision sentence through the context can be subjective and limited in qualitative analysis. In this paper, we evaluate the signaling effect of FOMC statements based on previous research. We analyze decision making characteristics from the viewpoint of text mining and try to predict future policy trend changes by capturing changes in expressions between statements. For this purpose, a decision tree and neural network models are used. As a result of the analysis, it can be judged that the discrepancy indicators between statements could be used to predict the policy change in the future and that the US Federal Reserve has systematically implemented policy signaling through the policy statements.

• Journal of Korean Society of Transportation
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• v.21 no.1
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• pp.103-113
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• 2003

This paper shows alternative route search and preference route search for the traffic route search, and proposes the use of the fuzzy non-additive controller by the application of AHP(analytic hierarchy process). It is different from classical route search and notices thinking method of human. Appraisal element, weight of route is extracted from basic of the opinion gathering for the driving expert and example of route model was used for the finding of practice utility. Model evaluation was performed attribute membership function making of estimate element, estimate value setting, weight define by the AHP, non additive presentation of weight according to $\lambda$-fuzzy measure and Choquet fuzzy integral. Finally, alternative route search was possible to real time traffic route search for the well variable traffic environment, and preference route search showed reflection of traffic route search disposition for the driver individual. This paper has five important meaning. (1)The approach is similar to the driver's route selection decision process. (2)The approach is able to control of route appraisal criteria for the multiple attribute. (3)The approach makes subjective judgement objective by a non additive. (4)The approach shows dynamic route search for the alternative route search. (5)The approach is able to consider characteristics of individual drivers attributed for the preference route search.

• Science of Emotion and Sensibility
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• v.11 no.1
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• pp.39-56
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• 2008

Previous studies of music, user interface, and human-computer interaction have used sounds which include musical structure rather than real music. This study investigated whether real music affects objective and perceived usability. Silence, sound, and music conditions were compared in experiment 1 (kimchi refrigerator) and 2 (remote controller for air conditioner). Participants' performances of reaction time and accuracy, and the degree of subjective satisfaction were analyzed. The results showed that main effects on task performances were not different significantly; however, perceived usability of music condition was better than sound condition, which was better than silence condition. It means that musical user interface improves perceived usability while not interfering task performance. This study provides a basis of emotional and aesthetic effects of music in home appliances design, and can be applied to studies for the blind. More specific guideline for the musical user interface can be drafted if further studies consider more various tasks, context, musical structure and types for the appliances.

• Korean Journal of Head & Neck Oncology
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• v.19 no.2
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• pp.164-169
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• 2003

Background and Objectives: The reconstruction is very important in Head and neck cancer surgery to repair the defect created by resection of tumors, to enable successful wound healing, to restore function and to provide acceptable cosmesis. The radial forearm free flap has been the most useful reconstructive flap because it provides a moderate amount of thin, pliable, relatively hairless skin and comparatively simple to do with minimal morbidity. The aims of this study is to estimate the outcome of the reconstruction with radial forearm free flap with the several factors in 140 head and neck cancer cases in our hospital for last 10 years. Materials and Methods: Retrospective review of the records of 140 patients underwent resection of the head and neck tumors and reconstruction with a radial forearm free flap from 1993 to 2003. The age, sex of the patients, Primary site, the complication of donor and recipient site, flap survival rate, median time to start diet, patient subjective symtoms about swallowing and articulating and the fact of revision reconstructive surgery were analyzed. Results: In primary pathologic site, 56 cases were oral cavity cancers, 44 cases, oropharyngeal cancers and 22 cases, hypopharyngeal cancers. Flap survival rate was 93.6% (13 leases). On donor site, wound dehiscence, hematoma, sensory change and infection were noted and on recipient site, most common complication were fistula and wound dehiscence. The complication rate of recipient's site was 19.1 % and donor site, 3.5%. In 118 cases (84.3%), the patients could take all kinds of food. Swallowing difficulty were noted in 22 cases 05.7%). In 5 cases, there was articulation difficulty but most of patients except patients having total laryngectomy (18 cases) couldn't have any difficulty in articulation and speaking. Conclusion: We conclude that the radial forearm free flap is the most appropriate reconstructive material for treating the defect in head and neck reconstruction.

• Science of Emotion and Sensibility
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• v.12 no.1
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• pp.77-86
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• 2009

A comfort evaluation of car seat clothing has been proposed for high comforts interior seat clothing. Car seat covers have received wide spread attention due to their man-machine interface working. And then, it will be necessary for measurements on delicate basic mechanical-properties, which closely relate with human touch feeling of its materials. In this research, we have utilized $KES-FB^{(R)}$(Kawabata Evaluation System) series, $^ST300{(R)}$ analogue softness tester and friction tester for measurement a physical properties. In order to consider both kansei and physical properties on interior seat covers, we firstly have established subjective words of judgement for the seat covers. Secondly, related them to the objective measurement of physical properties. Each kansei-language has clearly defined as 'Softness', 'Elasticity', 'Volume' and 'Stickiness' for the adjectives of leather car seat covers. These technical terms have correlated to physical properties in other words, h (mm), bending moment ($gf^*$cm/cm), To-Tm (mm) and ${\mu}$. At this time, fuzzy logic has utilized to predict the value of kansei language through physical values. On the basis of this result, finally it is possible to predict quality index of car seat covers using neural networks technique. In short, we develop a quality evaluation system of car seat clothing combining four physical quantities with kansei engineering.

• Korean Journal of Construction Engineering and Management
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• v.11 no.4
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• pp.22-31
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• 2010

Because the estimated cost at early stage has great influence on decisions of project owner, the importance of early cost estimation is increasing. However, it depends on experience and knowledge of the estimator mainly due to shortage of information. Those tendency developed into case-based reasoning(CBR) method which solves new problems by adapting previous solution to similar past problems. The performance of CBR model is affected by attribute weight, so that its accurate determination is necessary. Previous research utilizes mathematical method or subjective judgement of estimator. In order to improve the problem of previous research, this suggests CBR schematic cost estimation method using genetic algorithm to determine attribute weight. The cost model employs nearest neighbor retrieval for selecting past case. And it estimates the cost of new cases based on cost information of extracted cases. As the result of validation for 17 testing cases, 3.57% of error rate is calculated. This rate is superior to accuracy rate proposed by AACE and the method to determine attribute weight using multiple regression analysis and feature counting. The CBR cost estimation method improve the accuracy by introducing genetic algorithm for attribute weight. Moreover, this makes user understand the problem-solving process easier than other artificial intelligence method, and find solution within short time through case retrieval algorithm.