• Title/Summary/Keyword: Stepwise 회귀분석

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Surface roughness prediction with a full factorial design in turning (완전요인계획에 의한 선삭가공시 표면거칠기 예측)

  • Yang, Seung-Han;Lee, Young-Moon;Bae, Byong-Jung
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.1 no.1
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    • pp.133-140
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    • 2002
  • The object of this paper is to predict the surface roughness using the experiment equation of surface roughness, which is developed with a full factorial design in turning. $3^3$ full factorial design has been used to study main and interaction effects of main cutting parameters such as cutting speed, feed rate, and depth of cut, on surface roughness. For prediction of surface roughness, the arithmetic average (Ra) is used, and stepwise regression has been used to check the significance of all effects of cutting parameters. Using the result of these, the experimental equation of surface roughness, which consists of significant effects of cutting parameters, has been developed. The coefficient of determination of this equation is 0.9908. And the prediction ability of this equation was verified by additional experiments. The result of that, the coefficient of determination is 0.9718.

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Ecological Variables Affecting Library Satisfactions of Mothers of Early School-age Children (학령초기 아동 어머니의 도서관 이용만족도에 영향을 미치는 생태학적 변인 탐색)

  • Sang Eun Lee;Naya Choi
    • Journal of the Korean Society for Library and Information Science
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    • v.57 no.1
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    • pp.233-261
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    • 2023
  • Drawing on Bronfenbrenner's ecological system, the study explored the effect of the ecological variables affecting library satisfaction for mothers of early school-age children. The study used the eighth wave(2015) of Panel Study on Korean Children and conducted correlation analysis, multiple regression analysis, hierarchical regression analysis, and stepwise regression analysis. Researchers selected ecological variables for each ecological system based on previous studies. Results showed that mothers had moderate satisfaction with libraries, and their satisfaction with libraries was affected by library accessibility, satisfaction with public services, type of residence, children's reading time, and supportiveness of parenting policy. The study showed that external factors such as family, community, and policies could affect library satisfaction along with internal factors in the sociocultural context. The study suggested a possible practical implication for library policy.

Evaluation of the major sources of atmospheric pollution in jilin city by regression diagnostics (대기 오염이 암에 의한 사망률에 미치는 영향에 관한 연구)

  • 한지농;우치수
    • The Korean Journal of Applied Statistics
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    • v.2 no.2
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    • pp.47-51
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    • 1989
  • We study by stepwise regression method, the influence which atmospheric pollution in Jilin City has on the rate of death accorrding to cancer. The extremes are discovered and we know that $SO_2$ and smoking are important factors too.

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Effect of Career Commitment and Professionalism of Perioperative Nurses on the Organizational Commitment (수술실 간호사의 경력몰입과 전문직관이 조직몰입에 미치는 영향)

  • Yoon, Kesook
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.15 no.12
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    • pp.7193-7203
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    • 2014
  • This study examined the career commitment and professionalism of perioperative nurses and their impact on the organizational commitment. The subjects were 315 perioperative nurses who were attending the annual conference of the Korean Association of Perioperative Nurses. The data was analyzed by descriptive statistics, ANOVA, and stepwise multiple linear regression using the SPSS/PC 18.0 program. The average level of organizational commitment of the nurses was $3.04{\pm}.42$, whereas the level of career commitment and professionalism were $2.89{\pm}0.67$ and $3.04{\pm}0.29$, respectively. Both factors were found to be influencing factors on the organizational commitment. These variables explained 37.3% of the variance of organizational commitment, and the career commitment (${\beta}$=0.395) was a more influential factor than the professionalism (${\beta}$=0.298).

Fault-Causing Process and Equipment Analysis of PCB Manufacturing Lines Using Data Mining Techniques (데이터마이닝 기법을 이용한 PCB 제조라인의 불량 혐의 공정 및 설비 분석)

  • Sim, Hyun Sik;Kim, Chang Ouk
    • KIPS Transactions on Software and Data Engineering
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    • v.4 no.2
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    • pp.65-70
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    • 2015
  • In the PCB(Printed Circuit Board) manufacturing industry, the yield is an important management factor because it affects the product cost and quality significantly. In real situation, it is very hard to ensure a high yield in a manufacturing shop because products called chips are made through hundreds of nano-scale manufacturing processes. Therefore, in order to improve the yield, it is necessary to analyze main fault process and equipment that cause low PCB yield. This paper proposes a systematic approach to discover fault-causing processes and equipment by using a logistic regression and a stepwise variable selection procedure. We tested our approach with lot trace records of real work-site. A lot trace record consists of the equipment sequence that the lot passed through and the number of faults for each fault type in the lot. We demonstrated that the test results reflected the real situation of a PCB manufacturing line.

Analysis of Knowledge Community for Knowledge Creation and Use (지식 생성 및 활용을 위한 지식 커뮤니티 효과 분석)

  • Huh, Jun-Hyuk;Lee, Jung-Seung
    • Journal of Intelligence and Information Systems
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    • v.16 no.4
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    • pp.85-97
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    • 2010
  • Internet communities are a typical space for knowledge creation and use on the Internet as people discuss their common interests within the internet communities. When we define 'Knowledge Communities' as internet communities that are related to knowledge creation and use, they are categorized into 4 different types such as 'Search Engine,' 'Open Communities,' 'Specialty Communities,' and 'Activity Communities.' Each type of knowledge community does not remain the same, for example. Rather, it changes with time and is also affected by the external business environment. Therefore, it is critical to develop processes for practical use of such changeable knowledge communities. Yet there is little research regarding a strategic framework for knowledge communities as a source of knowledge creation and use. The purposes of this study are (1) to find factors that can affect knowledge creation and use for each type of knowledge community and (2) to develop a strategic framework for practical use of the knowledge communities. Based on previous research, we found 7 factors that have considerable impacts on knowledge creation and use. They were 'Fitness,' 'Reliability,' 'Systemicity,' 'Richness,' 'Similarity,' 'Feedback,' and 'Understanding.' We created 30 different questions from each type of knowledge community. The questions included common sense, IT, business and hobbies, and were uniformly selected from various knowledge communities. Instead of using survey, we used these questions to ask users of the 4 representative web sites such as Google from Search Engine, NAVER Knowledge iN from Open Communities, SLRClub from Specialty Communities, and Wikipedia from Activity Communities. These 4 representative web sites were selected based on popularity (i.e., the 4 most popular sites in Korea). They were also among the 4 most frequently mentioned sitesin previous research. The answers of the 30 knowledge questions were collected and evaluated by the 11 IT experts who have been working for IT companies more than 3 years. When evaluating, the 11 experts used the above 7 knowledge factors as criteria. Using a stepwise linear regression for the evaluation of the 7 knowledge factors, we found that each factors affects differently knowledge creation and use for each type of knowledge community. The results of the stepwise linear regression analysis showed the relationship between 'Understanding' and other knowledge factors. The relationship was different regarding the type of knowledge community. The results indicated that 'Understanding' was significantly related to 'Reliability' at 'Search Engine type', to 'Fitness' at 'Open Community type', to 'Reliability' and 'Similarity' at 'Specialty Community type', and to 'Richness' and 'Similarity' at 'Activity Community type'. A strategic framework was created from the results of this study and such framework can be useful for knowledge communities that are not stable with time. For the success of knowledge community, the results of this study suggest that it is essential to ensure there are factors that can influence knowledge communities. It is also vital to reinforce each factor has its unique influence on related knowledge community. Thus, these changeable knowledge communities should be transformed into an adequate type with proper business strategies and objectives. They also should be progressed into a type that covers varioustypes of knowledge communities. For example, DCInside started from a small specialty community focusing on digital camera hardware and camerawork and then was transformed to an open community focusing on social issues through well-known photo galleries. NAVER started from a typical search engine and now covers an open community and a special community through additional web services such as NAVER knowledge iN, NAVER Cafe, and NAVER Blog. NAVER is currently competing withan activity community such as Wikipedia through the NAVER encyclopedia that provides similar services with NAVER encyclopedia's users as Wikipedia does. Finally, the results of this study provide meaningfully practical guidance for practitioners in that which type of knowledge community is most appropriate to the fluctuated business environment as knowledge community itself evolves with time.

Association analysis between sports talent test scores and KOSTASS scores (스포츠영재성 검사 항목과 코스타스 점수간의 연관성 분석)

  • Park, Cheol-Yong;Lee, Mi-Sook
    • Journal of the Korean Data and Information Science Society
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    • v.22 no.1
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    • pp.57-64
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    • 2011
  • The Korea Sport Talent Search System (KOSTASS) can easily assess potential of Korean youth in 23 sport events and to identify sports talents who have high potential in track-and-field, swimming and gymnastics. The purpose of present study was to analysis relationship between sports talent test scores and KOSTASS scores. Physique, physical fitness, motor ability and physiological tests including skeletal age were administrated. Data of 201 elementary students who aged 7 to 12 living in Seoul area were collected. For pure association analysis, Pearson correlation coefficient and partial correlation coefficient are used and stepwise regression analysis is used for selecting important sports talent test scores. The results show that skeletal age, weight, chest circumference, 50-meter run, and half-squat jump have relatively low impact on six KOSTASS scores. The KOSTASS program would contribute to identify talented youth in sports among Korean youth population and success for international sports competition.

Comparisons of the Pan and Penman Evaporation Trends in South Korea (우리나라 증발접시 증발량과 Penman 증발량 추세 비교분석)

  • Rim, Chang-Soo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.5B
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    • pp.445-458
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    • 2010
  • The effects of geographical and climatic factors on annual and monthly pan and Penman evaporation were analyzed. 52 climatological stations were selected and trend analyses were performed. Furthermore, cluster analysis and multiple linear regression analysis were performed to understand the effects of geographical and climatic factors on pan and Penman evaporation. Based on stepwise multiple linear regression analysis, annual pan evaporation is proved to be mainly controlled by urbanization as geographical factor, and annual pan evaporation is also controlled by temperature, relative humidity, wind speed, and solar radiation as climatic factor. Especially wind speed is considered to be most significant climatic factor which affects pan evaporation. Meanwhile, Penman evaporation is not affected by geographical factors but it is affected by climate factors such as temperature, relative humidity, wind speed, and solar radiation except precipitation. Furthermore, the study results show that only proximity to coast affects pan evaporation trend on July; however, geographical and climatic factors do not affect pan evaporation trends in annual basis and monthly basis (January, April, and October). On the other hand, Penman evaporation trends were not affected by geographical factors in annual and monthly basises.

The Relationship Among Domain-General Creativity, Linguistic Intelligence, Korean Language Grade and Linguistic Creativity of Elementary School Student (초등학생의 일반창의성, 언어지능, 국어성적과 언어창의성 간의 관계연구)

  • Park, Jung-Hwan;Hong, Mi-Sun;Lew, Kyoung-Hoon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.8
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    • pp.3760-3767
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    • 2013
  • The purpose of this study is to investigate the relationship among domain-general creativity, linguistic intelligence, Korean language grade and linguistic creativity of elementary school student. And to confirm the relative predictive power of domain-general creativity variables in predicting elementary school students' linguistic creativity. The instruments used in this study were 'TTCT', 'Essay writing' and 'Linguistic intelligence ' and school grade of Korean language. Self-reported response data on these instruments from 338, 4th grade elementary school students in Seoul were analyzed. The data were analyzed with descriptive statistics, Pearson correlations, multiple stepwise regression analysis and ANOVA by using SPSS 18.0. The major results of this study were as follows; First, the correlations among domain-general creativity, Korean language grade and linguistic creativity were significant. Second, Abstractness of title were the best predictor of linguistic creativity in elementary school students.

Acoustic parameters for induced emotion categorizing and dimensional approach (자연스러운 정서 반응의 범주 및 차원 분류에 적합한 음성 파라미터)

  • Park, Ji-Eun;Park, Jeong-Sik;Sohn, Jin-Hun
    • Science of Emotion and Sensibility
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    • v.16 no.1
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    • pp.117-124
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    • 2013
  • This study examined that how precisely MFCC, LPC, energy, and pitch related parameters of the speech data, which have been used mainly for voice recognition system could predict the vocal emotion categories as well as dimensions of vocal emotion. 110 college students participated in this experiment. For more realistic emotional response, we used well defined emotion-inducing stimuli. This study analyzed the relationship between the parameters of MFCC, LPC, energy, and pitch of the speech data and four emotional dimensions (valence, arousal, intensity, and potency). Because dimensional approach is more useful for realistic emotion classification. It results in the best vocal cue parameters for predicting each of dimensions by stepwise multiple regression analysis. Emotion categorizing accuracy analyzed by LDA is 62.7%, and four dimension regression models are statistically significant, p<.001. Consequently, this result showed the possibility that the parameters could also be applied to spontaneous vocal emotion recognition.

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