• Title/Summary/Keyword: Path-analysis

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Transfer Path Analysis on the Passenger Car Interior Noise (승용차 실내소음의 전달경로 해석)

  • 지태한;최윤봉
    • Journal of KSNVE
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    • v.9 no.1
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    • pp.97-102
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    • 1999
  • Structure-borne noise is an important aspect to consider during the design and development of a vehicle. In this work. it was desired to identify the primary paths associated with structure-borne noise generated from the engine and front suspension. An experimental source-path-receiver model was used to characterize the system. A variety of primary sources such as engine. tires or exhaust system generate vibrations of the inner surfaces of the passenger compartment of a vehicle which subsequently radiate noise. The source was characterized by the force acting at the engine-to-body interface. and the path was characterized by pressure over force FRF's. The excitation forces were indirectly determined using dynamic stiffness of rubber mount or the system accelerance matrix. Through these analysis, path contribution diagram which is well expressed primary noise path is obtained.

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Patient Safety Management Activities of Korean Nurses: A Meta-Analytic Path Analysis (국내 간호사의 환자안전관리활동에 대한 메타경로분석)

  • Jeong, Seohee;Jeong, Seok Hee
    • Journal of Korean Academy of Nursing
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    • v.52 no.4
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    • pp.363-377
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    • 2022
  • Purpose: This study aimed to test a hypothetical model of Korean nurses' patient safety management activities using meta-analytic path analysis. Methods: A systematic review, meta-analysis, and meta-analytic path analysis were conducted following the PRISMA and MOOSE guidelines. Seventy-four studies for the meta-analysis and 92 for the meta-analytic path analysis were included. The R software program (Version 3.6.3) was used for data analysis. Results: Four variables out of 49 relevant variables were selected in the meta-analysis. These four variables showed large effect sizes (ESr = .54) or median effect sizes (ESr = .33~.40) with the highest k (number of studies) in the individual, job, and organizational categories. The hypothetical model for the meta-analytic path analysis was established using these variables and patient safety management activities. Twelve hypothetical paths were set and tested. Finally, the perception of the importance of patient safety management and patient safety competency directly affected patient safety management activities. In addition, self-efficacy, the perception of the importance of patient safety management, patient safety competency, and patient safety culture, indirectly affected patient safety management activities. Conclusion: Self-efficacy, the perception of the importance of patient safety management, patient safety competency, and the organization's patient safety culture should be enhanced to improve nurses' patient safety management activities.

A Study on Employment Path of Vocational Instructors Using Sequential Analysis (순차분석을 활용한 직업능력개발훈련교사의 입직경로 분석)

  • Kim, Min-Jeong;Lee, Young-Min
    • The Journal of the Korea Contents Association
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    • v.21 no.10
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    • pp.78-89
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    • 2021
  • This study aims to identify the employment path of vocational instructors using sequential analysis. By grasping the employment path in detail, the study presents implications for implementing support measures for systematic preparation for employment. In particular, the study presents the relationship of the vocational instructor's employment path in stages through frequency analysis, conversion probability analysis, significance test, and conversion status diagram of each employment path. For the analysis, the survey results of the vocational instructors working at private vocational training institutions were used. In conclusion, (i) as for the frequency of past experience for employment as a vocational instructor, the share of work experience, teaching training, and teaching experience was large. (ii) In the employment path stage, work experience, teaching training, and teaching experience had the greatest influence on the transition to the later stage. (iii) The prominent employment path for vocational instructors was "work experience-teaching experience-teaching training." Based on the conclusions, the study proposes a plan for systematic employment of vocational instructors.

Transfer Path Analysis and Estimation of the Road Noise for the Driving Vehicle (주행 차량의 로드 노이즈 예측을 위한 각 입력원의 기여도 평가)

  • Yang, In-Hyung;Jeong, Jae-Eun;Yoon, Ji-Hyun;Oh, Jae-Eung
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.20 no.11
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    • pp.1071-1077
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    • 2010
  • The reduction of the vehicle interior noise has been the main interest of noise and vibration harshness(NVH) engineers. A passenger vehicle has various and complicated transmission paths of sound and vibration. In order to identify the mechanism of transfer path, estimation of excitation force and exact modeling of transfer path are required. This paper presents method for estimating the noise source contribution on the road noise of the vehicle in a multiple input system where the input sources may be coherent with each other. And vector synthesis technique is employed to identify the characteristics of road noise and its transmission to vehicle compartment through noise and vibration analysis. Vibration reduction efficiency of each transfer path is evaluated by comparing individual vector components obtained virtual simulation.

Transfer Path Analysis of the Vehicle Interior Noise according to Excitation Existence or not (차량 가진원 유무에 따른 실내소음의 전달경로 분석에 대한 연구)

  • Park, Jong-Ho;Lee, Sang-Kwon
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2011.04a
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    • pp.365-370
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    • 2011
  • Structure-bone noise is an important aspect to consider during the design and development of a vehicle. Reduction of structure-bone noise of the compartment in a vehicle is an important task in automotive engineering. Many methods which analyze transfer path of noise have been used for structure-bone noise. The existing method to measure of frequency response function of transfer path has been tested by removing a source. This Paper presents an experimental analysis about Transfer Path Analysis of the vehicle interior noise according to Excitation or not. To identify these points of difference, experiment were conducted through an experimental test using simulation vehicle.

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A Study on the Visibility Analysis Model for the Ward of General Hospital Considering Nurse's Circulation (종합병원 병동부 간호 이동 동선을 고려한 가시 특성 분석 모델에 관한 연구)

  • Kim, Seo-Yeong;Kweon, Jihoon
    • Journal of the Regional Association of Architectural Institute of Korea
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    • v.20 no.6
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    • pp.71-80
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    • 2018
  • The path and visibility of nurses in general hospital wards have been treated as architectural planning factors. However, the analysis approach of existing studies shows limitations that only fixed physical elements are considered without considering the behavior of users using space. Consider factors for analysis of ward and models based on this study model. Select a case hospital to apply the analysis technique and conduct the nurse questionnaire and route survey of the hospital. Establish a framework for analysis model applied with the path of nurse movements. The analysis model applies to the case hospital. The analysis results are aggregated to derive design suggestion for reference to the spatial improvement of the ward. Visible visibility to observe the bedside in the nursing station, visibility to observe the beds in the nurse's path, and visibility to observe patients moving in the nurse's path were derived from visual access frequency and exposure frequency. The survey of nurses' movements at the site allowed the nurses to calculate the distance required to move. Reflecting the path of nurse movement, a model was presented for a comprehensive analysis of nursing distance and nursing visibility, which could lead to improvement in the observation and visibility of nurses and the layout of patient rooms or day rooms.

Contribution Analysis of Simulated Pass-by Data using Operational Transfer Path Analysis

  • Lohrmann, Martin;Kluiber, Florian
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2010.05a
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    • pp.123-125
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    • 2010
  • As the exterior noise emitted by a vehicle is getting more and more attention, simulated pass-by measurements become more important. This well established method provides information about the total noise emitted by the vehicle. For a vehicle manufacturer it is not only interesting to know about the total noise but also to know how this total exterior noise is composed of different contributions, such as for example the contribution of the engine, the intake or exhaust system. Transfer path analysis (TPA) provides a separation of these contributions for each of the pass-by microphones alongside the track. Presented is a method for fast and efficient determination of the contributions of multiple sources using operational transfer path analysis (OTPA). The calculation of the transfer characteristics between the reference measurement points on the vehicle and the corresponding response points of both microphone lines are carried out while operation of the vehicle. As result of the contribution analysis from operational transfer path analysis, the characteristic noise level as function of the covered distance is displayed for all individual sound sources, thus providing in depth information for sound quality engineering.

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Path Analysis of Factors Limiting Crop Yield in Rice Paddy and Upland Corn Fields (벼와 옥수수 재배 포장에서 경로분석을 이용한 작물 수확량 제한요인 분석)

  • Chung S. O.;Sudduth K. A.;Chang Y. C.
    • Journal of Biosystems Engineering
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    • v.30 no.1 s.108
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    • pp.45-55
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    • 2005
  • Knowledge of the relationship between crop yield and yield-limiting factors is essential for precision farming. However, developing this knowledge is not easy because these yield-limiting factors are interrelated and affect crop yield in different ways. In this study, data for grain yield and yield-limiting factors, including crop chlorophyll content, soil chemical properties, and topography were collected for a small (0.3 ha) rice paddy field in Korea and a large (36 ha) upland corn field in the USA, and relationships were investigated with path analysis. Using this approach, the effects of limiting factors on crop yield could be separated into direct effects and indirect effects acting through other factors. Path analysis provided more insight into these complex relationships than did simple correlation or multiple linear regression analysis. Results of correlation analysis for the rice paddy field showed that EC, Ca, and $SiO_2$ had significant (P<0.1) correlations with rice yield, while pH, Ca, Mg, Na, $SiO_2,\;and\;P_2O_5$ had significant correlations with the SPAD chlorophyll reading. Path analysis provided additional information about the importance and contribution paths of soil variables to rice yield and growth. Ca had the highest direct effect (0.52) and indirect effect via Mg (-0.37) on rice yield. The indirect effect of Mg through Ca (0.51) was higher than the direct effect (-0.38). Path analysis also enabled more appropriate selection of important factors limiting crop yield by considering cause-and-effect relationships among predictor and response variables. For example, although pH showed a positive correlation (r=0.35) with SPAD readings, the correlation was mainly due to the indirect positive effects acting through Mg and $SiO_2$, while pH not only showed negative direct effects, but also negatively impacted indirect effects of other variables on SPAD readings. For the large upland Missouri corn field, two topographic factors, elevation and slope, had significant (P<0.1) direct effects on yield and highly significant (P<0.01) correlations with other limiting factors. Based on the correlation analysis alone, P and K were determined to be nutrients that would increase corn yield for this field. With the help of path analysis, however, increases in Mg could also be expected to increase corn yield in this case. In general, path analysis results were consistent with published optimum ranges of nutrients for rice and com production. We conclude that path analysis can be a useful tool to investigate interrelationships between crop yield and yield limiting factors on a site-specific basis.

The study for effectiveness of golf skills to adjust average score using path analysis in 2010 PGA (2010 미국프로골프협회 자료를 활용한 경로분석을 통한 경기력의 평균타수에 미치는 영향력 비교)

  • Min, Dae-Kee
    • Journal of the Korean Data and Information Science Society
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    • v.22 no.1
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    • pp.65-71
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    • 2011
  • Path analysis is a useful method to find out direct or indirect effects between variables. Compared to regression analysis for studying the casual relationship, this method has a good advantage. In this study, I want to figure out direct or indirect relationships between golf skills and adjust average scores using path analysis. To analyze data, I applied AMOS in SPSS and collected data in 2010 PGA.

A Study on Country and Brand Image of Foreign Automobile Products - A Focus on Path Analysis of U. S and Japanese Brands - (외국 자동차 제품의 국가이미지와 브랜드이미지에 대한 연구 - 미국과 일본 브랜드의 경로분석을 중심으로 -)

  • Seo, Min-Kyo;Lee, Chun-Su
    • International Commerce and Information Review
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    • v.9 no.1
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    • pp.23-41
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    • 2007
  • This paper research the country image, the brand image, consumers' performances and the brand royalty with the path analysis on foreign automobile brands. Our empirical study testify the reliability analysis, the factor analysis and the path analysis with above variables by SPSS 12.0 and AMOS 4.0. The result of this research is that hypotheses H1, H3, H5 were significantly supported, whereas, hypotheses H2, H4 were rejected in the samples of American automobile. and in the samples of Japanese automobile, it was clearly revealed that hypotheses H2, H3, H4 were significantly supported, whereas, hypotheses H1, H5 were rejected. So, in Korean market, we should focus on the brand image strategy more than the country image to make the brand royalty with American automobile products. whereas, Japanese automobile products, another strategy is recommended.

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