• 제목/요약/키워드: Quantitative Methodology

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실차 운행정보를 활용한 온실가스 배출지표 분석 방법에 대한 연구 (A Study on the Analysis Method of Emission Intensity of GHGs utilizing Real World Vehicle Driving Information)

  • 김용범;김필수;한용희;이헌주;장영기
    • 한국기후변화학회지
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    • 제7권1호
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    • pp.19-29
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    • 2016
  • In this study, the emission intensity calculation method of GHGs was developed by considering the characteristics of the models and time series. The telematics device was installed on the car (OBD-II) to collect information on the operation conditions from each sample vehicle of public authorities. Based on emission intensity of GHGs, it presented a methodology of quantitative comparison of GHGs emission by vehicles. Collected driving information of vehicle was used for operating characteristics analysis of the target vehicle, and it was confirmed different operating characteristics through comparison of the results and previous study. GHGs emission intensity were analyzed considering characteristics of vehicle type by passenger car, van, cargo, and considering characteristics of the time series by summer, winter, and intermediate. From the analysis result, it was calculated GHGs emission intensity based on mileage ($g\;CO_2\;eq./km$) and operating time ($g\;CO_2\;eq./sec$).

완전분해 점검을 통한 장기운영 전투기 전기배선시스템의 신뢰성분석 (EWIS Reliability Analysis of Aging Fighter Aircraft through Teardown Inspection)

  • 이호용
    • 한국항공운항학회지
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    • 제26권4호
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    • pp.116-121
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    • 2018
  • According to the incresement of aging aircraft, Republic of Korea Air Force (RoKAF) conducted a teardown inspection of aircraft's EWIS (electrical wiring interconnection system) to determine the status of deterioration and the influence of failure occurrences due to it. The inspected aircraft were the retired fighter jets that had been used for more than 40 years. By analyzing defect type and the defect tendency, RoKAF can establish the necessary measures for the usage extension of their fleet and furthermore, the analysis results can be used as a basic data for the preparation of it's aircraft aging. EWIS inspection was done throughout careful visual inspection technique by removing all the ducts and pipes located in the fuselage and wings. For the aircraft wiring where no damage was found, the elongation tests were performed to determine the deterioration of wiring according to the location of the aircraft. The connectors, which is the main cause of intermittent failure, were completely disassembled and inspected for internal damage such as corrosion, abrasion, and traces of foreign objects. The detected defects were classified into 4 severity levels based on the type of damage, and the classified defects were weighted according to the criticality which may affects to it's system to establish the action plan.

A combined experimental and numerical study on the plastic damage in microalloyed Q345 steels

  • Li, Bin;Mi, Changwen
    • Structural Engineering and Mechanics
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    • 제72권3호
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    • pp.313-327
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    • 2019
  • Damage evolution in the form of void nucleation, propagation and coalescence is the primary cause that is responsible for the ductile failure of microalloyed steels. The Gurson-Tvergaard-Needleman (GTN) damage model has proven to be extremely robust for characterizing the microscopic damage behavior of ductile metals. Nonetheless, successful applications of the model on a given metal type are limited by the correct identification of damage parameters as well as the validation of the calculated void growth rate. The purpose of this study is two-fold. First, we aim to identify the damage parameters of the GTN model for Q345 steel (Chinese code), due to its extensive application in mechanical and civil industries in China. The identification of damage parameters is facilitated by the well-suited response surface methodology, followed by a complete analysis of variance for evaluating the statistical significance of the identified model. Second, taking notched Q345 cylinders as an example, finite element simulations implemented with the identified GTN model are performed in order to analyze their microscopic damage behavior. In particular, the void growth rate predicted from the simulations is successfully correlated with experimentally measured acoustic emissions. The quantitative correlation suggests that during the yielding stage the void growth rate increases linearly with the acoustic emissions, while in the strain-hardening and softening period the dependence becomes an exponential function. The combined experimental and finite element approach provides a means for validating simulated void growth rate against experimental measurements of acoustic emissions in microalloyed steels.

의료서비스 마케팅 국내 연구동향 분석 (Analysis of research trends in healthcare service marketing)

  • 김우진;김지만;신재용;김태현;이상규
    • 한국병원경영학회지
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    • 제24권1호
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    • pp.21-35
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    • 2019
  • Purposes: This study examines academic research trends and the change of patterns by analyzing researches related to healthcare service marketing from 1988 to 2016. Methodology: As research subjects, a total of 486 published articles were selected. It's to analyze them by dividing into research topics, methods and data by classifying the period into 1988-1999, 2000-2009, 2010-2016. Findings: From 1988 to 2016, 486 research articles on healthcare service marketing were published in academic journals. Research on healthcare service marketing has steadily increased. Most of the articles were about service quality, satisfaction, revisitation, and reuse. 452 research articles were quantitative research. Generally questionnaire surveys were used. Practical Implications: We suggest future research directions on the basis of the status of research on healthcare service marketing for the last 30 years.

실험계획법을 이용한 입구덕트 스프레이의 습식 세정 효율 변화효과 분석 연구 (Quantitative Analysis of the Impact of Inlet Duct Spray on Scrubbing Efficiency using Experimental Design)

  • 이민우;김현호;구준모
    • 한국분무공학회지
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    • 제24권1호
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    • pp.8-14
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    • 2019
  • The purpose of this study is to develop a packing-free wet scrubber to prolong the maintenance interval compared with the conventional packed bed wet scrubbers with which frequent operation stops are unavoidable to clean the packing materials. The main- and interaction-effects were quantitatively analyzed by regression analysis for the measured ammonia scrubbing data from the experiments prepared by experimental design. The scrubbing efficiency of the newly developed wet scrubber was found to be over 95% under the condition of flue gas flow rate of 90CMM and liquid-to-gas ratio $2l/m^3$ for all considered trials of experimental design. The interaction effect between the inlet duct spray and the filter was found to be important, which controls the droplet growth due to the droplet collisions between the duct- and scrubbing tower-spray. The presented methodology to analyze the impacts of operational and design factors on the scrubber efficiency showed potential for applications to optimize the future flue gas abatement process in semiconductor plants.

간호대학생의 임상실습 시 의사소통 경험에 대한 현상학적 연구 (A Phenomenological Study on the Experiences of Nursing Students' Communication in Clinical Nursing Practicum)

  • 김동희;송효빈;손해경
    • 의료커뮤니케이션
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    • 제13권2호
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    • pp.195-204
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    • 2018
  • Background: Unlike traditional quantitative study, this qualitative study is designed to understand and explore the experiences of nursing students's communication in clinical nursing practicum. Methods: Participants were 15 nursing students from a university in Seoul who were selected by purposive sampling. They had been participated in clinical nursing practicum more than one semester. Data were collected through in-depth interviews and observation from May 29, 2017 to June 8, 2017. Collected data were analyzed by Colaizzi's phenomenological methodology. Results: As a result, 5 theme clusters were derived as follows: 1) the modeling of communication, 2) treatment as a student nurse, 3) respect as a nurse, 4) trauma after communication, and 5) sympathy in communication. This study identified the desire for nursing professionalism, psychological difficulties as negative emotionality, as well as positive emotionality of nursing students in clinical practicum. Conclusion: We should consider a nursing curriculum to prepare and improve the communication of nursing students before participating in clinical practicum. The concrete and systematic communication education would be useful for nursing students to participate clinical practicum effectively.

On a New Index for Research Assessment

  • Farid, Farid O.
    • Journal of Information Science Theory and Practice
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    • 제9권3호
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    • pp.56-75
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    • 2021
  • We introduce a new research assessment measure, called the research excellence index. The measure, which we denote by RE-index, accurately assesses the research performance of a researcher. The methodology used in deriving the RE-index tackles many of the flaws of popular research performance indicators such as publication counts, citation counts, and the h and g indices. A dataset is introduced, which takes advantage of the wide coverage of Scopus and the Library of Congress, and, at the same time, deals with the Scopus database depth problem. For an academic publication x, a prestige-type and length scores are assigned, and if x is published in an academic periodical publication J, the stature of J is identified through a quartile score. The three scores are used to assign a value score to every academic publication, and cited academic publications are given citation scores that encompass both cases of including and excluding self-citations. The foregoing scores are used to derive another set of scores measuring the combined qualitative and quantitative aspects of the creative work, citations of creative work, informative work and citations of informative work of a researcher. The scores take into consideration co-authorship. From these scores, two versions of the RE-index for a researcher are derived, covering the cases of including and excluding self-citations. The new measure is calculated for two mathematicians.

지역사회경험학습(Community Based Learning: CBL) 기반 대학 통일관광경영 수업 모듈 개발 (Unification Tourism Management Class Module Developed by Community Based Learning(CBL))

  • 우은주;박은경;김영국
    • 아태비즈니스연구
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    • 제11권3호
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    • pp.261-271
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    • 2020
  • Purpose - This study was to establish a unified tourism management class for university students based on Gangwon-do. Community based learning(CBL) was applied to provide a tangible and intangible resource of tourism resources the theoretical approaches and the actual experiences of the community. Design/methodology/approach - In order to design a unified tourism management module, this study applied qualitative research and quantitative research methods to collect information on the direction of the module. the study conducted in-depth interviews and then an online survey. Findings - According to the results of the study, the main parts should include necessity of unification, inter-Korean tourism, inter-Korean cooperation, inter-Korean economy, and international relations. Research implications or Originality - The overall composition of the unification tourism management class should be designed as the unification tourism management theory to acquire the subject knowledge, the field trip to the border area for experiential learning, and the assignment of the field study task to understand the community.

How Much does Job Autonomy Matter for Job Performance of Chinese Supervising Engineers: A Quantitative Study

  • CUI, Nan;XIAO, Shu-Feng
    • 동아시아경상학회지
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    • 제9권3호
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    • pp.71-82
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    • 2021
  • Purpose - The purpose of this study is to examine the intermediary role of job satisfaction between job autonomy and job performance and whether the process was adjusted based on the work context. Research design, data, and methodology - This study was conducted by sample survey method on 334 supervising engineers. Data analysis methods were frequency analysis, confirmatory factor analysis, reliability analysis, correlation analysis, and structural equation model analysis. Result - The results of this study suggest that: (1) after controlling for age, position, and working years, job autonomy had a significant positive impact on job performance, (2) job autonomy can not only directly affect job performance but also indirectly affect performance through job satisfaction, (3) job satisfaction has an intermediary effect on job autonomy and job performance, and (4) the relationship between job autonomy and job satisfaction is moderated by the work context, and the result showed a negative moderating effect. Conclusion - This study suggests that job autonomy significantly improves job performance, and the higher job autonomy a supervising engineer has, the more satisfied they are with their work, thus enriching the precursor research on dynamic changes in job performance. When the working environment is poor, supervisors are more sensitive to the perception of job autonomy and have a stronger impact on job satisfaction and performance.

The Relationship between Coolness, Perceived Value and Value Creation: An Empirical Study of Fashion Distribution

  • Truong, Nguyen Xuan;Ngoc, Bui Hoang;Phuong, Pham Thi Lan
    • 유통과학연구
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    • 제19권9호
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    • pp.101-111
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    • 2021
  • Purpose: This study discusses and discovers the important role of fashion product coolness in affecting consumers' perceived value and consumers' value creation behavior. Accordingly, fashion product coolness exerts a direct effect on perceived value while perceived value has a direct impact on value creation. Besides, fashion product coolness has an indirect effect on value creation through perceived value. Research design, data, and methodology: This study adopts the quantitative research approach by cross-sectional technical on a sample of 319 respondents in Vietnam. PLS-SEM has been used to analyze the survey data. Results: The result indicates that the proposed direct and indirect effects are significant. Specifically, utilitarian "coolness" and hedonic "coolness" have positive impacts on perceived value. The perceived value poses an impact on consumers' value creation behavior, including customer lifetime value and influencer value. Finally, the perceived value links utilitarian "coolness", hedonic "coolness" with customer lifetime value and influencer value. Conclusions: Fashion distribution is playing an increasingly important role in the retail sector of the economy. Fashion distribution activities are greatly influenced by the perceived value of consumers. The findings are supposed to strengthen the beliefs of fashion brands and retailers in the promotion of value creation and consumers' perceived value in the field of fashion distribution.