• The Journal of the Korean dental association
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• v.58 no.3
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• pp.169-179
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• 2020

The purpose of this study was to investigate the principal reasons for primary teeth extractions and the tooth type extracted in children. 1159 patients were selected in this study. Dental records and radiographs were reviewed and age, gender, medical history, type of tooth extracted and the reasons for extraction were collected. The data were statistically analyzed using Chi-square test. Total 2078 primary teeth were extracted. Central incisors(34.1%) were most frequently extracted. Extractions due to physiological mobility(77.5%) were the most frequent followed by caries(13.8%), orthodontic(3.9%), trauma(1.7%). Reason for the extraction was different according to age (p = 0.000), but there was no difference according to gender (p = 0.109). While extractions due to physiological mobility predominated overall, reason for extraction was different according to the tooth type. There was no previous treatment in 54.6% of primary teeth extracted due to caries. Excluded physiological mobility, caries are the most common reason for extraction of primary teeth. The importance of preventive care should be emphasized in order to preserve primary teeth and improve children's oral health.

• Journal of the Korea Safety Management & Science
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• v.20 no.3
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• pp.21-26
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• 2018

This paper describes result of a study on safety against a fire of charging cable for mobile phone for vehicle. Combustion on the USB cable in the car was happened while driving. Gas coming from the burning USB cable could be a reason which can make a secondary car accident since the driver also can be embarrassed while driving. In order to prevent a secondary car accident connected on the road, to research a reason why USB cable can emit gas and be burned in charging. We did simulation test with abnormal fault condition for the electronic component on the board in the USB cable. So we get the result from abnormal fault condition simulation test, for instance, shorted test for output terminal of 8 pin switch, shorted test for chip resistor after thermal aging in the condition $25^{\circ}C$, 93 % RH during 48 hours. To analysis the result of all test, Combustion on the USB cable was not the 8 pin but other electrical component such as a chip resistor. Therefore we guess that the reason for USB cable combustion in charging in a car was not 8 pin and a LED but another defective component.

• Journal of the Korea Fashion and Costume Design Association
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• v.19 no.1
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• pp.15-25
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• 2017

The purpose of this study was to investigate the effect of sports shoes benefit pursuit on purchase reason, purchase evaluative criteria, and purchase information resource of high school girls. The data were collected between June 2016 from 287 high school girls in their's, living in Seoul, Daejeon, Gwangju, Daegu, Busan, and Changwon. The data have been analyzed by using SPSS program. The methods of factor analysis, reliability, and regression have been adopted for the data analysis. The results of this study were as followings: The factors of sports shoes benefit pursuits consisted of four dimensions of fashion-pursuit, brand-pursuit, convenience-pursuit, and economy-pursuit. The factors of purchase reasons consisted of three dimensions of syntony, recreation, and economic utility. The factors of purchase evaluative criteria consisted of three dimensions of management, aesthetic appreciation, and symbolism. The factors of purchase information resource consisted of two dimensions of media and human. Sports shoes benefit pursuits had an influence on purchase reasons, purchase evaluative criteria, and purchase information resources. In particular, the fashion-pursuit of Sports shoes benefit pursuits had a great influence on purchase reasons. The brand-pursuit of Sports shoes benefit pursuits had a great influence on purchase evaluative criteria and purchase information resources. It is highly expected that this study is used as the useful sources of sports Shoes industry.

• Archives of design research
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• v.12 no.2
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• pp.53-62
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• 1999

The modern is image age, and The visually expressed symbols have much influence on individuals or enterprises and have an effect on the variety of individual and the innovation of management. Espacially, the symbols carry on the axis composing total image. According to the reason of positive & negative five elements, this paper analysised and studied the meaning of symbol design which analysis the thoughtful, abstract and formal meaning. This is the most fundmental elements and principals and means the good symbol composed harmoniously the positive & negative five elements give good image. Namely, the symbols of the Eum & Yan which applied the philosophical reason of the Orient thought became good image. The lively elements of design composed the reason of Eum & Yang have effect on auspicious and upgrade one step to the dimension of symbol design. The purpose of this paper analysises and understands the meaning of symbol was composed the positive & negative five elements. In the point of view of modern design. the overlOOking elements of the symbol(line, form, space etc) reminded and established the new model which the new idea approached by the thought of the positive & negative five elements.

• Journal of Korean Classical Literature and Education
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• no.16
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• pp.237-272
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• 2008

In this thesis I aim at investigating at the distinctive characteristic of homesickness in written by Hong sun-hag and the mean of the distinctive characteristic. The result as follow. The aspect of homesickness in the Yeonhaengnok : The first, the traveler express the reason that cause the homesickness. The reason that cause the homesickness is various. The second, the traveler express the emotional conflict between worry about the family and ambition of travel in Yeonhaengsanmun. The third, the traveler express the reason that cause the homesickness and yearn for his home. The traveler express the individual experience connected with the family in Yeonhaengsanmun, the universal experience connected with the family in Yeonhaenghansi. The distinctive characteristic of homesickness in the and the mean of the distinctive characteristic : The first, the aspect of homesickness in the is all aspect of homesickness. The author of synthesizes homesickness. The second, the scenery rouse the traveler' homesickness and the traveler expresses homesickness by the empathy to the scenery. The mean of expressing by the scenery is that the expression succeed the 17th century Yeonhaenggasa. The third, the traveler concretely expresses his inner world. The mean of concretely expressing the inner world is that the expression is related to the realism of expressing the inner world.

• The Korean Journal of Emergency Medical Services
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• v.22 no.3
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• pp.177-187
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• 2018

Purpose: The purpose of the study was to investigate the causes of non-transport in 119 ambulance services and to describe the difference in response time according to the reason for non-transport. Methods: This study analyzed 42,415 non-transport cases out of 123,158 cases using prehospital care reports in a metropolitan city. The Kruskal-Wallis test and the Wilcoxon-Mann-Whitney test were used to 6,857 cases for which time was recorded. Results: Non-transportation in 20${\bigcirc}{\bigcirc}$ comprised 33.1% of all ambulance services. The reason for non-transport were other reasons (25.5%), cancellation (23.8%), and moving to other vehicles (21.7%). There were differences in ambulance service times according to the reasons for non-transport. The activation interval was the longest (2.68 minutes) in the absence of the patient, and the response interval was the shortest (4.96 minutes) among the cancelled case. The total interval was the shortest time (21.97 minutes) in the cancellation cases and the longest time among the death cases (32.23 minutes). Conclusion: It is important to suggest the direction of development of emergency services by identifying the reasons for non-transport by ambulance services and describing the response time according to the reason for non-transport.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.123-124
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• 2021

Recently, the danger of fine dust has emerged worldwide. In general, fine dust refers to particulate matter less than 10㎛ and ultrafine dust less than 2.5㎛, and according to the announcement by HEI (Health Impact Research Institute) in 2015, the concentration of ultrafine dust in Korea is the second highest among OECD member countries. It was investigated. In this study, an experiment was conducted to analyze how the diatomaceous earth substitution rate affects the strength characteristics of the permeable block. As the replacement rate of diatomaceous earth increased, the strength decreased. The reason why the strength decreases with the use of diatomaceous earth is that the strength of the hardened body decreases as the structure of the hardened body becomes less dense as the amount of diatomaceous earth increases, and the reason that the strength decreases as the replacement rate of diatomaceous earth increases is the reason for the absorption performance of diatomaceous earth. Therefore, it is judged that a void was generated inside the hardened body while water was absorbed and then evaporated or discharged in the matrix, and accordingly, the strength decreased.

• East Asian mathematical journal
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• v.39 no.4
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• pp.455-478
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• 2023

Expectations and interests in blended learning are increasing as universities respond to the educational flow of transition to e-lernring. This study tried to explore and understand the meaning of and the properties of blended instruction. In addition, through the literature review, this study was to find out how bleanded learning affected in teaching and learning situation. Particularly, it was to find out students' preference to the type of blended instruction. Those types are the mixed of or the unique of class instruction(off line), on line, and recorded instruction. To investigate learners' preference to the type of the instruction and also the reason of the preference, in this study, the 27 undergraduate students of the fourth grade in the major of mathematics education in the C university located in G area. By the result, most students preferred the mixed type of instruction involving off line and recorded instruction. The reason is that they could attend to the class while participating in the group activity positively and understand the content through the communication in depth and the instructor's feedback. Because of this reason, they did not prefer to the only one type insturction such as the recorded type.

• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.409-419
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• 2016

The purpose of this study is to examine the differences of selecting coffee shop and type of coffee according to the reason for the visit. The proposed model was empirically tested by using survey data collected from 209 university students in Seoul and Gyeonggi Province. SPSS has been used to preform this analysis. The study found six reasons for visiting Coffee shops which are convenience, social contact, psychological factor, economic factor, mental factor, and habitual visit. As we gorup these six reasons into three groups, students who visit coffee shops according to economic or habitual factor consider more on 'diversity of coffee'. And students who visit coffee shops according to convenience or habitual factor consider more on 'kindness of worker'. And last group who visit coffee shops according to social factor consider more on 'moderate price of coffee'. The reason why the reason for the visit and the attributes of selecting Coffee Shop are not meaningful to the type of coffee which students chose is that most of students tend to choose certain type such as Americano. And this also result from the traditional managements which don't have enough effort or the differentiation about the variety of menu.

• Journal of Dental Rehabilitation and Applied Science
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• v.35 no.3
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• pp.143-152
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• 2019

Purpose: The aim of this study is to investigate the characteristics of patients and teeth referred to a university dental hospital for endodontic problem. Materials and Methods: From January, 2017 to December, 2018, patients who were referred to a university dental hospital for endodontic problem were collected from clinical records. A total of 1171 patient records were analyzed. The status of the referred teeth was divided into three groups according to whether they were treated endodontically based on radiographs and clinical records at the time of referred visit. Results: 69.9% of the referred teeth were maxillary and mandibular first and second molars. The average time from referral to actual visit is 9.03 days and 65.6% of the case referred with referring letter. The most primary reasons of referral were persistent clinical symptom (pain, swelling, and sinus tract) (37.9%), diagnosis difficulty (16.7%), blockage of canal space (13.8%) and difficult tooth anatomy (11.4%). In the case of referral before endodontic treatment, the most primary reason of referral was failure to make a proper diagnosis. If the teeth were referred in the middle of endodontic treatment, the most primary reason of referral was persistent clinical symptom and blockage of canal space. In the case of referral after root canal filling, the most primary reason of referral was persistent clinical symptom. Conclusion: In the case of molars, the rate of persistent clinical symptom and blockage of canal space were the most primary reason of referral, and the rate of apical surgery and management of trauma was high in the case of anterior teeth.