국소의치용 티타늄의 피로도 및 물리적 성질에 관한 연구

김학선,김광남,장익태 서울大學校 齒科大學 1993 齒大 論文集 Vol.17 No.2

Elicitation of design factors through big data analysis of online customer reviews for washing machines

김학선,노유정 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.6

The volume of online consumer-generated content, such as opinions, personal feelings, and design requirements continually increases. However, the analysis of the large quantity of data available is not systematic, and customers’ opinions and requirements are not properly utilized in product design. In this study, big data on customers’ experience with front loading washers, represented by reviews and ratings on the BestBuy website, were collected and used to analyze the relationship between the customers’ experience and the associated satisfaction by using text analytics. Words related to customer satisfaction that occurred frequently in the reviews were extracted, and the most significant words among them were selected as inputs for finding the major factors relevant to washer design by performing factor analysis. The influence of each factor was quantitatively estimated through linear regression analysis. This shows that the quantitatively elicited customer information from the big data can provide insights for new washing machine design.

ZigBee 기술 동향

김학선 한국정보통신설비학회 2005 한국정보통신설비학회 세미나 Vol.2005 No.1

[선생님, 우리 선생님] 영아의 짝궁 길들이기

김학선 샘터사 1999 월간 샘터 Vol.30 No.3

마이크로파 중합에 의한 의치상 레진의 물리적 성질에 관한 연구

김학선,김광남,장익태,Kim, Hak Sun,Kim, Kwang Nam,Chang, Ik Tae 대한치과보철학회 1990 대한치과보철학회지 Vol.28 No.2

The purpose of this study was to investigate the physical propertise and determine whether three were any differences in the amount of porosity of the denture base resins cured by microwave irradiation and conventional water bath heating. The resins used in this study were K-33 resin and Acron MC resin. The properties selected were transverse strength, Knoop hardness, and density. A ten-power eyepiece and scanning electron microscope(Magnification of ${\times}$ 30and ${\times}$150)were used to examine the specimens for porosity. Through analyses of the data from this study, the following conclusions were obtained. 1. Microwave energy can be effectively use dtopolymerize poly(methylmethacrylate) denture base resins. 2. In the transverse strength, K-33 resin cured by microwave irradiation was the first highest, water bath cured K-33 resin the second, microwave cured Acron MC resin the third, water bath cured Acron MC resin the fourth. 3. In the Knoop hardness, K-33 resin cured by microwave irradiation was the first hardest, water bath cured K-33 resin the second, water bath cured Acron MC resin the third, microwave cured Acron MC resin the the fourth. 4. No significant difference was found between the density of resin denture bases polymerized by either method. 5. K-33 resin showed the most porosity for the microwave curing. But there was no significant difference in the Acron MC resin and other curing method.

Comparison of Surgical Outcomes in Thoracolumbar Fractures Operated with Posterior Constructs Having Varying Fixation Length with Selective Anterior Fusion

김학선,Seung Yup Lee,Ankur Nanda,Ju Young Kim,박진오,문성환,이환모,김호중,Huan Wei,문은수 연세대학교의과대학 2009 Yonsei medical journal Vol.50 No.4

Purpose: Surgical treatment in the case of thoracolumbar burst fractures is very controversial. Posterior instrumentation is most frequently used, however, but the number of levels to be instrumented still remains a matter of debate. Materials and Methods: A total of 94 patients who had a single burst fracture between T11 and L2 were selected and were managed using posterior instrumentation with anterior fusion when necessary. They were divided into three groups as follows; Group I (n = 28) included patients who were operated by intermediate segment fixation, Group II (n = 32) included patients operated by long segment fixation, and Group III (n = 34) included those operated by intermediate segment fixation with a pair of additional screws in the fractured vertebra. The mean follow-up period was twenty one months. The outcomes were analyzed in terms of kyphosis angle (KA), regional kyphosis angle (RA), sagittal index (SI), anterior height compression rate, Frankel classification, and Oswestry Disability Index questionnaire. Results: In Groups II and III, the correction values of KA, RA, and SI were much better than in Group I. At the final follow up, the correction values of KA (6.3 and 12.1, respectively) and SI (6.2 and 12.0, respectively) were in Groups II and III found to be better in the latter. Conclusion: The intermediate segment fixation with an additional pair of screws at the fracture level vertebra gives results that are comparable or even better than long segment fixation and gives an advantage of preserving an extra mobile segment. Purpose: Surgical treatment in the case of thoracolumbar burst fractures is very controversial. Posterior instrumentation is most frequently used, however, but the number of levels to be instrumented still remains a matter of debate. Materials and Methods: A total of 94 patients who had a single burst fracture between T11 and L2 were selected and were managed using posterior instrumentation with anterior fusion when necessary. They were divided into three groups as follows; Group I (n = 28) included patients who were operated by intermediate segment fixation, Group II (n = 32) included patients operated by long segment fixation, and Group III (n = 34) included those operated by intermediate segment fixation with a pair of additional screws in the fractured vertebra. The mean follow-up period was twenty one months. The outcomes were analyzed in terms of kyphosis angle (KA), regional kyphosis angle (RA), sagittal index (SI), anterior height compression rate, Frankel classification, and Oswestry Disability Index questionnaire. Results: In Groups II and III, the correction values of KA, RA, and SI were much better than in Group I. At the final follow up, the correction values of KA (6.3 and 12.1, respectively) and SI (6.2 and 12.0, respectively) were in Groups II and III found to be better in the latter. Conclusion: The intermediate segment fixation with an additional pair of screws at the fracture level vertebra gives results that are comparable or even better than long segment fixation and gives an advantage of preserving an extra mobile segment.

호텔종사원의 감정노동이 이직의도에 미치는 영향: 감정소진의 매개효과와 직무열의의 조절효과

김학선,안창숙,채주아,전재균 경성대학교 산업개발연구소 2024 산업혁신연구 Vol.40 No.4

This study aims to analyze the impact of emotional labor on turnover intention among hotel employees, focusing on the mediating role of emotional exhaustion and the moderating effect of job engagement. Emotional labor is a common phenomenon in the hotel industry, where employees frequently need to suppress or regulate their emotions during interactions with customers. The study categorizes emotional labor into surface acting and deep acting to examine their distinct effects. The findings indicate that surface acting increases emotional exhaustion, which in turn raises turnover intention. In contrast, deep acting helps reduce emotional exhaustion and subsequently lowers turnover intention. Emotional exhaustion plays a crucial mediating role between emotional labor and turnover intention, as the depletion of emotional energy directly influences employees' intention to leave the organization. Furthermore, the study investigates whether job engagement moderates the relationship between emotional labor and emotional exhaustion. Employees with high job engagement experience relatively lower emotional exhaustion from surface acting, suggesting that job engagement acts as a buffer, mitigating the negative effects of emotional labor. Highly engaged employees are more immersed in their work and, therefore, are less affected by the adverse impacts of emotional labor. This study emphasizes the need for organizational efforts to manage emotional labor and alleviate emotional exhaustion in the hotel industry, offering practical strategies to reduce turnover rates and improve organizational performance.

고속 신호처리를 위한 스위치드 커패시터 회로 설계에 관한 연구 ( A Study on the Design of Switched Capacitor Building Block for High-Speed Signal Processing )

김학선,김경월,이형재 한국통신학회 1992 한국통신학회 학술대회논문집 Vol.11 No.1

숲에서 유아의 흙 놀이 과정 분석

김학선 한국홀리스틱융합교육학회 2017 홀리스틱융합교육연구 Vol.21 No.2

이 연구는 숲이라는 환경 속에서 매일 흙을 이용하여 자유롭게 놀이하는 유아의 흙 놀이 과정을 분석하는 데 목적을 두었다. 연구대상은 I시에 소재한 매일형 숲반으로 만4세 11명, 만5세 9명으로 총 20명이다. 2016년 3월 3일(목)부터 12월 21일(수)까지 연구자가 매일 유아들의 일과 속으로 들어가 참여관찰을 하였다. 수집된 자료를 분석한 결과 유아들의 흙 놀이 과정은 ‘인식하기’, ‘적응하기’, ‘목적 있는 놀이하기’, ‘자연물 추가하기’, ‘함께 확장하기’의 단계로 범주화 되었다. 이를 구체적으로 살펴보면, ‘인식하기’는 유아가 흙의 존재를 인식하는 단계이고, ‘적응하기’는 유아가 흙을 파고, 담고, 옮기는 등의 행동이 반복적으로 이루어지는 단계이다. ‘목적 있는 놀이하기’는 유아가 의미를 정해놓고 흙 놀이를 하는 단계이며, ‘자연물 추가하기’는 숲에 있는 다양한 자연물을 추가하여 흙 놀이를 하는 단계이다. 마지막으로 ‘함께 확장하기’는 유아들이 자연스럽게 역할을 나누어 통합적으로 흙 놀이를 진행시키는 단계이다. 이와 같은 결과는 유아의 흙놀이가 일정한 단계를 거쳐 자연스럽게 다른 유아들과의 통합적 놀이로 확장되기 때문에 자유로운 흙 놀이가 진행될 수 있는 환경이 제공되어야 함을 시사하고 있다. The purpose of this study was analyzing processes of the children’s free soil play as they perform their daily activities in the forest. Ethnographic research as the method of the study was used, as the researcher analyzed 20 children with ages of 4 to 5 by participatory observation of the daily activities of 'I Grand Park Forest class' from March to december, 2016. The results of free soil play process were analyzed are summarized below. The children's soil playing is five processes ; ‘Recognize’, ‘Adapt’, ‘Play with purpose’, ‘Adding a natural product’, ‘Expand together'. If you look at it concretely, ‘Recognize’ is a step of the children recognizes the existence of the soil. ‘Repeat ' is the repetition of the behavior of the children, such as dig, put in and move of the soil, etc. ‘Play with purpose' means playing with the purpose when the children plays. 'Adding a natural product' is a step in the process of adding a variety of natural objects in the forest. Lastly, 'Extension of playing' is a step in the process of allowing childrens to play naturally and proceed with soil play. as a result, children who enjoy soil play naturally expand into integrated play, so there should be an environment where free soil play can be played.

프랜차이즈 및 대리점의 육계 공급업체 선정에 영향을 미치는 요인에 관한 연구

김학선,정안성,신동훈 한국산업경제학회 2019 산업경제연구 Vol.32 No.2

The purpose of this study is to reconstruct the supplier selection criteria suitable for the broiler industry and to test the factors influencing the broiler supplier selection for the franchisees and agent purchasing managers. In addition, a study was conducted to demonstrate what factors among broker supplier selection factors affect overall supplier satisfaction. As a result of the validity and reliability analysis of broiler supplier selection factors, broiler supplier selection was summarized as supply factor, price factor, quality factor, salesperson factor, and brand factor. The purchasing manager considered the supply factor as the most important factor when selecting the broiler supplier, followed by the price factor, the salesperson factor, the quality factor, and the brand factor. The results of verifying the difference in the importance of broiler supplier selection factors according to general characteristics of purchasing managers and surveyed companies are as follows. First, 'supply factors' and 'salesperson factors' showed no significant difference in selection of broiler vendors according to general characteristics of purchasing managers and surveyed companies. Second, 'price factor', 'quality factor' and 'brand factor' showed significant difference in selection of broiler supplier according to general characteristics of purchaser and surveyed companies. The results of the multiple linear regression analysis were as follows to examine the effect of the importance of the factors considered in the selection of broiler supplier to the satisfaction of the purchasing managers. 'Quality factor', 'salesperson factor', and 'brand factor' of the broiler suppliers were found to affect the satisfaction. The results of this study are basic data on factors influencing the selection of suppliers for broiler buyers and we hope that broiler vendors will use them to establish effective business directions and strategies based on the analysis results. 본 연구의 목적은 육계산업에 적합한 공급업체 선정기준을 재구성하고, 프랜차이즈 및 대리점 구매담당자를 대상으로 육계 공급업체 선정에 영향을 미치는 요인이 무엇인지를 실증하는 것이다. 또한, 육계 공급업체 선정요인 중 어떠한 요인이 전체 공급업체 만족도에 영향을 미치는지를 실증하는 연구를 진행하였다. 육계 공급업체 선정요인에 대한 타당도 및 신뢰도 분석을 실시한 결과, 육계 공급업체를 선정하는 요인은 공급요인, 가격요인, 품질요인, 영업담당자요인, 브랜드요인으로 요약되었다. 구매담당자가 육계 공급업체를 선정할 때 공급요인을 가장 중요하게 고려하는 것으로 나타났고, 그 다음으로 가격요인, 영업담당자요인, 품질요인, 브랜드요인 순으로 중요하게 고려하는 것으로 나타났다. 구매담당자 및 조사대상업체의 일반적 특성에 따라 육계 공급업체 선정요인의 중요도 차이를 검증한 결과는 다음과 같다. 첫째, ‘공급요인’, ‘영업담당자요인’은 구매담당자 및 조사대상업체의 일반적 특성에 따라 육계 공급업체 선정시 중요도 차이가 없는 것으로 나타났다. 둘째, ‘가격요인’, ‘품질요인’, ‘브랜드요인’은 구매담당자 및 조사대상업체의 일반적 특성에 따라 육계 공급업체 선정시 중요도 차이가 있는 것으로 나타났다. 조사대상업체 구매담당자의 육계 공급업체 선정시 고려하는 요인에 대한 중요도가 만족도에 미치는 영향을 살펴보기 위해 다중선형회귀분석을 실시한 결과, 육계 공급업체의 ‘품질요인’, ‘영업담당자요인’, ‘브랜드요인’에 대한 중요도가 만족도에 영향을 미치는 것으로 나타났다. 본 연구결과는 육계 구매담당자가 공급업체를 선정하는데 영향을 받는 요인이 무엇인지에 대한 기초적인 자료로써, 분석결과를 토대로 육계 공급업체가 효과적인 사업 방향 및 전략을 수립하는데 활용하기를 기대한다.