• 제목/요약/키워드: Exogenous Variable

검색결과 103건 처리시간 0.023초

철도관제사의 사고유발 요인에 관한 탐색적 구조분석 (An Exploratory Structural Analysis of the Accident Causing Factors in Railway Traffic Controllers)

  • 김경남;신택현
    • 한국시뮬레이션학회논문지
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    • 제27권1호
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    • pp.119-126
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    • 2018
  • 본 연구는 철도관제사의 인적오류를 유발하는 요인이 무엇인지를 AMOS 구조방정식 모형을 활용하여 탐색적으로 검증하려는 목적에서 시도되었다. 관제사와 관련된 문헌연구를 토대로 피로와 스트레스를 외생변인, 정보처리과정에서의 오류(인지, 기억, 저장 및 실행오류)를 내생변인, 그리고 종속변인으로 책임사고와 아차사고를 설정하였다. 여러 기관의 현직관제사 201명의 설문을 분석한 결과, '스트레스 ${\rightarrow}$ 기억오류 ${\rightarrow}$ 저장오류 ${\rightarrow}$ 아차사고 ${\rightarrow}$ 책임사고'의 인과관계 고리가 성립한다는 것을 발견하였다. 이 같은 연구결과는 인적오류와 관련하여 관제사의 사고 저감을 위해서는 그 선행요인인 스트레스를 효과적으로 관리하여 정보처리과정에서의 기억 및 실행오류를 저감시킬 필요가 있다는 것을 시사한다.

홀로식사와 대사증후군의 관련성: 구조방정식 모형을 이용한 위험요인 분석 (Association between Eating Alone and Metabolic Syndrome: A Structural Equation Modeling Approach)

  • 송수연;정윤희
    • 대한영양사협회학술지
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    • 제25권2호
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    • pp.142-155
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    • 2019
  • The aim of this study was to construct and test a structural equation model for the risk factors of metabolic syndrome in Korean adults. The structural equation model hypothesizes that eating alone and feeling depressed is a risk factor for metabolic syndrome. The data of this study were obtained from the Sixth Korea National Health and Nutrition Examination Survey which was cross-sectional data from the representative national survey. A total of 4,013 subjects replied to the survey item of lifestyle and completed the physical examinations among adults aged 19 years or older in South Korea was in 2015. The structural model in this study was composed of four latent variables: eating alone, depression, negative health behavior, and metabolic syndrome. Two variables, the rate of eating alone and depression, were exogenous variables. Negative health behavior was both a mediating variable and endogenous variable, and metabolic syndrome was the final endogenous variable. The data were analyzed using the Maximum Likelihood method and bootstrapping. The structural model was appropriate for the data based on the model fit indices. The results of this study can be summarized as follows: Eating alone is a direct risk factor of metabolic syndrome in Korean women. Depression can mediate metabolic syndrome through negative health behaviors. Negative health behavior had a direct impact on metabolic syndrome in both men and women. This study may be a guideline for interventions and strategies to reduce the incidence of metabolic syndrome in Korean adults.

여성의 체중조절행위 모형 구축 (A Study on the Development of Weight Controlling Health Behavioral Model in Women)

  • 전연숙;이종렬;박천만
    • 보건교육건강증진학회지
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    • 제23권4호
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    • pp.125-153
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    • 2006
  • This study was intended to describe women's weight controlling by creating a hypothetic model on the weight adjustment behavior and by examining a cause and effect relationship, and to contribute to countermeasures for practicing their promotion of health and improving the quality of life through creating a predictable model. The subject of study was women who utilize the beauty shop located in Seoul, Busan and Daegu and the study period was 12 weeks from July 10 to September 30 in 2004. Gathered 1093 person's general specialty related with weight adjustment and analyzed covariance to prove the hypothesis using statistics compiled from authentic sources. Also proved coincidence of the hypothetical model. Exogenous variables of the hypothetical model are composed of recognition of her body shape, fatness level, age, stress, and self-respect. Endogenous variables are health- control mind, recognized health state, self-efficacy, intention, and behavior of weight adjustment. There were 5 measured variables for exogenous variable(x). There were 8 measured variable(y) for exogenous variable. And coincidence $x^2=297.38$, standard $x^2(x^2/df)=7.08$, GFI=0.962, AGFI=0.917, NFI=0.875, TLI=0.794, CFI=0.889, RMSEA=0.075. The result of hypothesis had an epoch-making record that 20 out of 27 hypothesis was proved positive way. Generally weight adjustment has been highly seen in housewives, the married and the old age. Health control mind seems to be high as fatness level, age, and self-respect are high and low stress. Recognized health state is high as age and self-respect are high and low stress. However, it is not much related with recognition of her body shape and fatness level. If age, self-respect, health control mind, recognized health state and self-efficacy are high intention of behavior is also high, but intention of behavior has no relation with recognition of her body shape, fatness level and stress. If fatness level, age, self-respect, health control mind, recognized health state and self-efficacy and intention of behavior are high, execution of weight adjustment will be high. However, recognized health state and stress has no influence for weight adjustment. To increase the coincidence of hypothesis and take a simple model I modified a model and then I got the coincidence $x^2=215.62$, standard $x^2(x^2/df)=6.34$, GFI=0.970, AGFI=0.931, NFI=0.902, TLI=0.901, CFI=0.915, RMSEA=0.070. This result is a bit better than original hypothetical model's so that this model might be more suitable. In this modification model, the factors of weight adjustment seems to be high according to this order self-efficacy, recognized health state, age, intention, health control mind, self-respect, fatness level and stress. With this result I suggest ; 1. Enforcement of IR that everybody can be controlled weight adjustment herself and continuous education, which is related with regular habit (food, exercise, restriction of a favorite food and behavior training etc.) is also needed. 2. Because self-efficacy is influenced to execution of weight adjustment specific program which can increase self-efficacy should have to develop and we need to utilize it to take care of herself. 3. To protect fatness and be active weight adjustment the peculiar program including the concept of self-respect, recognized health state, health control mind and intention must be developed and not only women but also all of people should be educated. 4. This hypothetical model is forecasting women's weight adjustment behavior and can be utilized for fundamental data to increase those people's health.

정맥주사용 수액의 개방후 시간경과에 따른 오염도에 관한 실험연구 (A Study on the Relationship Between Length of Time and Contamination in Open Intravenous Solutions)

  • 김일원
    • 대한간호학회지
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    • 제16권1호
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    • pp.67-80
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    • 1986
  • The use of intravenous solutions for fluid replacement has become an integral part of patient care, This widespread use of intravenous solutions has increased the risk of contamination that can lead to septicemia and phlebitis. The literature regarding contamination of in use intravenous solutions recommends a standard 24-hour time limit on the use of these fluids. But the desings of these studies did not incorporate a time variable related to contamination. In other studies, however, time was a manipulated variable: but data regarding the onset of contamination were conflicting. Because published reports conflict with regard to a time standard related to the use of intravenous therapy, additional empirical data are needed upon which to base the standards of care regulating use of intravenous therapy. This study investigated rate of contamination in simulated in-use intravenous solutions to obtain data from which to recomend a standard time period for the administration of intravenous solutions. In this study samples were drawn from 60 bottles of 5% D/W solution at predetermined time intervals over 48 hours and samples were inoculated to Thio-glychollate Broth. After 10 days' culturing in that Broth, samples were cultured on blood agar plates for 18∼48 hours to determine the rate of contamination. was found at all time Period, regardless of the presence or absence of nurse's gloving in the preparation of fluids, the location in which the experimentations were performed, the contamination level of surrounding air, or the length of time during which solutions were opened. Data from this study support the use of a 48-hour time period on which to base the standard involved in ready-to-use simple intravenous solutions without additives. In emergency departments and critical care areas where intravenous solutions are prepared in advance, the suggested time standard supported by the data generated from this study is 48 hours, not 24 hour. Data from this study support a 24-hour time standard for changing in-use intravenous solutions when the contamination results from the manipulation of intravenous infusion system by hospital personnel, or from some other exogenous sources during administration. Because contamination that does occur within 48 hours in intravenous solutions must be introduced from some exogenous sources, further empirical studies based on the identification of sources of contamination and factors that affect the rate of contamination, are needed to investigate the currently employed standard of intravenous therapy and to provide the patient with more efficient and safer intravenous thereapy.

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다변량 시계열 모형을 이용한 컨테이너선 시장 분석 (Analysis of Container Shipping Market Using Multivariate Time Series Models)

  • 고병욱;김대진
    • 한국항만경제학회지
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    • 제35권3호
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    • pp.61-72
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    • 2019
  • 본 연구는 컨테이너 해운산업의 경쟁력 제고와 발전을 위해 다변량 시계열 모형을 이용한 컨테이너선 시장의 실증적 분석에 기초하여 컨테이너 해운시장의 동태적 움직임에 대한 전략을 제시하고자 했다. 분석 방법론으로는 벡터자기회귀모형(VAR), 벡터오차수정모형(VECM) 등의 다변량 시계열 모형을 사용했다. 실증분석을 위해 컨테이너선 시장의 연간 운송량, 선박량, 운임 자료를 활용했다. 분석 결과에 따르면, 가장 외생적 변수인 운송량 변수가 전체 컨테이너선 시장의 동태적 움직임에 가장 큰 영향을 미친다는 것을 확인할 수 있었다. 이러한 실증분석 결과에 기초하여 본 논문은 선박 투자, 운임 예측, 선사의 전략 수립 등에 대한 시사점을 제시했다. 선박 투자와 관련해서는 해운시장의 외생 변수인 운송량이 운임 불확실성에 가장 큰 비중을 차지하고 있기 때문에 미래 운임수입 흐름에 기반한 프로젝트 금융 보다는 운항 선주의 재무적 안정성을 강조하는 기업 금융 방식이 컨테이너선 투자의 위험관리에 적합하다는 것을 알 수 있다. 운임예측과 관련해서는 미래 예측대상 시점의 변수 값을 사용하는 단순 회귀 예측에 비해 과거의 값만으로 예측값을 도출할 수 있는 VAR 모형 또는 VECM 모형이 보다 현실성이 있다는 점을 살피고 있다. 마지막으로 선사의 전략 수립과 관련하여 시황과 연계한 원리금 상환 계약과 화주와의 운송 계약 도입을 권고하고 있다.

스마트폰의 사용 용이성과 유용성이 전환장벽과 고객충성도에 미치는 영향 (Effects of Ease of Use and Usefulness of Smart Phones on Switching Barrier, Customer Loyalty)

  • 이진춘
    • 한국산업정보학회논문지
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    • 제16권5호
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    • pp.115-126
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    • 2011
  • 본 연구는 한국이동통신시장에서 새로운 제품과 서비스인 스마트폰이 도입됨에 따라 용이성과 유용성이 전환장벽, 고객만족과 고객충성도에 미치는 영향을 분석하는데 초점을 두었다. 본 연구는 용이성을 외생변인으로 하고, 유용성, 전환장벽, 고객만족과 고객충성도를 내생변인으로 하여, 변인 간의 영향관계를 파악하는 구조방정식모형을 설계하였다. 본 연구에서는 기술수용 모형에서 유래한 용이성과 유용성을 도입하여 품질과 고객만족 관계를 연결하여 그 영향관계를 분석하였다.본 연구에서는 스마트폰의 사용 용이성과 유용성이 미치는 영향관계 경로를 6개 가설로 구축하여 검정하였다. 가설검정을 위해서 452명을 대상으로 설문조사를 실시하여 자료를 수집하였으며, AMOS19와 SPSS19를 이용하여 실증분석을 하였다. 검정결과는 다음과 같다. 첫째, 스마트폰 용이성과 유용성은 전환장벽에 유의한 영향을 미치고 있었다. 둘째, 용이성은 유용성에 유의한 영향을 미치고 있으며, 셋째, 유용성은 고객만족에 유의한 큰 영향을 주고 있었다.

상호작용효과에 의한 고령자 사고 추가발생비용 추정에 대한 연구 (A Study of the Estimation of Additional Costs on the Car Accident for Senior People Due to Interaction Effects)

  • 윤병조
    • 도시과학
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    • 제6권2호
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    • pp.59-72
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    • 2017
  • Studies on the calculation of accident costs include the approach on calculating damage costs covering all accidents regardless of first or secondary party and the one calculating damage costs generated by a single victim. These two approaches have a limitation of considering a subject for costs analysis as a single entity. In addition, research on estimating the interaction effects caused in the relationship between diverse traffic accident features and factors remains inadequate since most studies focused on calculating costs incurred in a single entity such as a victim, damaged building, or social organization in charge of managing car accident. This study intends to identify the expected range of old age where a specific interaction effect would remain, compare accidents between old age section and the entire age section, and discover an exogenous variable to be applied in accident drop effects in senior people and reduced benefits by calculating and testing additional accident costs in case the first party and the second party all pertain to the senior age section. By classifying the entire accidents caused by old drivers according to the types of cars, significant coefficients representing the influence that affects car accidents according to the characteristics are calculated and set them as the representative variables by selecting top variable in accordance with from low to high order. Furthermore, characteristics on five age groups such as a group of over 65 and less than 70, a group of over 70 and less than 75, a group of over 75 and less than 80, a group of over 80 and less than 85, and a group of over 85 are elicited and compared them with these preselected accident characteristics variables, thereby identifying what changing effects come out.

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CCTV융합채널의 마케팅믹스가 대리점 행태에 미치는 영향분석 (Effects of Marketing Mix on Behavior of Authorized Dealers in the Korean CCTV Converging Channels)

  • 이진춘
    • 디지털융복합연구
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    • 제13권4호
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    • pp.89-100
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    • 2015
  • 본 연구는 우리나라 CCTV융합채널 업계에서 마케팅믹스의 특성이 브랜드 이미지, 대리점 지각, 전환장벽과 대리점의 충성도에 미치는 영향을 분석하는데 초점을 두고 있다. 본 연구는 마케팅 믹스요인을 외생요인으로 하고 브랜드 이미지, 대리점 지각, 전환장벽을 매개변인으로 하고, 대리점 충성도를 결과변인으로 하는 구조방정식모형으로 구축하였다. 본 연구에서는 8개의 가설을 설정하고, 전국의 191개 업체를 대상으로 설문조사하여 얻은 자료를 AMOS20과 SPSS20을 이용하여 분석하였다. 그 결과, 마케팅 믹스 중 제품공급과 가격이 브랜드 이미지에 유의한 영향을 미쳤으며, 광고만이 대리점 지각에 영향을 미치고 있음이 나타났다.

의류상품 소비에 있어서 가격수용성의 상호관련변수 (Correlates of Price Acceptability of Apparel Products)

  • 이규혜
    • 한국의상디자인학회지
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    • 제10권3호
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    • pp.127-136
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    • 2008
  • The main focus of the study resides in antecedents of price acceptability. Levels of acceptable price may be related to the consumers' perception on reasonable or expected price. Price acceptability is known to have several psychological antecedents. One of the antecedents to price acceptability reported by prior researches is price-quality inference, a tendency to correlate high price to excellence in quality. In addition, price-conscious consumers are likely to show lower level of price acceptability level. Another well-known antecedent is sale proneness. Sales-prone consumers may relate price of apparel products to product quality information. Moreover, it was reported that involved consumers should be more concerned with the products to its price and thus should have higher levels of price acceptability. A conceptual model with price consciousness, sale proneness and product involvement as the exogenous variable, price-quality inference and price acceptability as the endogenous variable was developed for the empirical study. Measures of research variables were developed based on previous studies. Questionuaires from 298 respondents were analyzed for the study. The average age of respondents was 27. About 60% of the respondents were married and about 65% of them had college degrees. Empirical results supported all of the hypothesized relationships. Price consciousness had significant negative influence on price-quality inference and price acceptability. Sale proneness significantly influenced price-quality inference, while apparel involvement had significant impact on price-quality inference and price acceptability. Price-quality affected price acceptability significantly. This study generated a framework to help scholars understand antecedents of price acceptability of apparel products. Price has been shown to playa dual role in consumer's perceptions, either positively or negatively. Price consciousness played a negative role, and product involvement had a positive role in evoking higher level of price acceptability. This study also suggests additional source of positive, yet indirect role of price, sale proneness. This study also affirmed the importance of price-quality inference in arousing higher level of price acceptability.

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우울증을 매개로 한 청소년의 자살구상에 관한 가족 및 학교환경의 경로분석 모델 (Path Model for the Family and School Environment Affecting Adolescent Suicidal Ideation Mediated by Depression)

  • 전영주
    • 대한가정학회지
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    • 제39권1호
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    • pp.151-167
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    • 2001
  • This study tests the path model which examines how the variables of past and present family dynamics, school adjustment, filed life events affect the adolescents'depression which in tum influencing their suicidal ideation. In the path model, the exogenous varialbes were negative parenting experience in childhood, maladjustment history of the family (e.g., alcohol, divorce), present parent-adolesecent communication, school adjustment, filed life events were used, whereas the adolescent depression was used as the mediated variable. The endogenous variable was the adolescent suicidal ideation. The respondents of the survey were 635 adolescent who were 1st and 2nd grade of high school located in Seoul and Busan. Using SPSS for Windows, the path analysis was done for male and female adolescents separately, since female adolescents were found to report significantly higher degree of depression and suicidal ideation then were male adolescents. The results of the path analysis were as followings. First, for both the male and female adolescents, depression was the strongest predictor of their suicidal ideation. Also, school adjustment strongly affected the adolescents'depression as well as their suicidal ideation. Meanwhile, filed life events indirectly influenced the suicidal ideation only through the depression. Second, for the male adolescents, negative parenting experience in childhood affected both the depression and suicidal ideation, while the parent-adolescent communication directly affected the suicidal ideation. Third, for the female adolescents, maladjustment family history and negative parenting experience did not affect their depression, but the suicidal ideation. Meanwhile, parent-adolescent communication was a significant predictor of female adolescents'suicidal ideation as well as their depression. In conclusion, discussion on different path of male and female adolescents'suicidal ideation was provided.

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