• Title/Summary/Keyword: frequency and correlation analysis

Search Result 2,822, Processing Time 0.03 seconds

Studies on the vibrational modal analysis of solid woods for the violin making II, Effect of annual ring width and cutting direction on the resonant frequency of the bridges (바이올린용 소재의 진동모드 해석에 관한 연구 -제2보. 소재 연륜폭 및 절삭방향이 브릿지의 공진주파수에 미치는 영향)

  • Chung Woo-Yang
    • Journal of the Korea Furniture Society
    • /
    • v.16 no.1
    • /
    • pp.17-23
    • /
    • 2005
  • European maple is famous for the optimum solid wood for making bridge which is the most important part in violin acoustics. This study was carried out to investigate the variation of main features, i. e. annual ring width and cutting direction of costly imported violin bridge blanks and to examine the effect of these features of the blanks on the vibrational characteristics of bridge blanks. Imported violin bridge blanks had somewhat large variation in major macroscopical and physical properties and there was little relationship between annual ring density and weight of maple blanks. Resonant frequency of violin bridge blanks had some positive correlation with weight, however, damping having negative relationship with frequency was seldom affected by any physical properties of the maple blanks. Deviation from the radial cutting of tail side(ray direction from top toward feet on the edge of bridge blank) lowered the resonant frequency. Consequently, weight and ray direction should be taken for the critical quality decisive factors(QDF) of incoming bridge blanks by not only inspectors also luthiers who tune the bridge by shaping and are responsible for the final timbre quality of this complicate instrument.

  • PDF

A study on the Relationships of Core-Self Evaluation, Work-Family Facilitation, Job Satisfaction and Turnover Intention (핵심자기평가(CSE)와 일-가족 지원, 직장만족 그리고 이직의도의 관계 연구)

  • Choi, Hyun-Jung
    • Culinary science and hospitality research
    • /
    • v.17 no.4
    • /
    • pp.219-237
    • /
    • 2011
  • This study aims to investigate the effect of core-self evaluation on work-family facilitation(work to family facilitation, family to work facilitation), job satisfaction and turnover intention among non-regular workers in Korean food service industry. In order to examine the hypothesized relationships, frequency analysis, confirmatory factor analysis, reliability analysis, correlation analysis and covariance structure analysis were performed using SPSS(10.0) and AMOS(4.0). The results showed that core-self evaluation had a significantly positive effect on both of work to family facilitation and family to work facilitation. In the case of relationship between work-family facilitation and job satisfaction, only family to work facilitation had a positive effect on job satisfaction while there was no evidence of a significant relationship from work to family facilitation to job satisfaction. Additionally, job satisfaction had a significantly negative effect on turnover intention. The article concluded with managerial implications for managerial and future research directions.

  • PDF

A Text Mining Analysis on Students' Perceptions about Capstone Design: Case of Industrial & Management Engineering (텍스트 마이닝을 활용한 캡스톤 디자인에 관한 학생 인식 탐색: 산업경영공학 사례)

  • Wi, Gwang-Ho;Kim, Yun-jin;Kim, Moon-Soo
    • Journal of Engineering Education Research
    • /
    • v.25 no.5
    • /
    • pp.85-93
    • /
    • 2022
  • Capstone Design, a project-based learning technique, is the most important curriculum that clarifying major knowledge and cultivating the ability to apply through the process of solving problems in the industrial field centered on the student project team. Accordingly, various and extensive studies are being conducted for the successful implementation of capstone design courses. Unlike previous studies, this study aimed to quantitatively analyze the opinions that recorded the experiences and feelings of students who performed capstone design, and used text mining methodologies such as frequency analysis, correlation analysis, topic modeling, and sentiment analysis. As a result of examining the overall opinions of the latter period through frequency analysis and correlation analysis, there was a difference between the languages used by the students in the opinions according to gender and project results. Through topic modeling analysis, 'topic selection' and 'the relationship between team members' showed an increase in occupancy or high occupancy, and topics such as 'presentation', 'leadership', and 'feeling what they felt' showed a tendency to decreasing occupancy. Lastly, sentiment analysis has found that female students showed more neutral emotions than male students, and the passed group showed more negative emotions than the non-passed group and less neutral emotions. Based on these findings, students' practical recognition of the curriculum was considered and implications for the improvement of capstone design were presented.

A Study on the Architectural Planning for Space for Stay in the Ward Based on the Analysis of User Behavior - Chronic Patient Ward in Korea Workers' Compensation Hospital (이용자 행태 분석을 통한 병동부 체류 공간에 관한 건축계획 연구 - 근로복지공단병원 병동부 공용공간을 중심으로)

  • Son, Jihye;Yang, Naewon
    • Journal of The Korea Institute of Healthcare Architecture
    • /
    • v.22 no.3
    • /
    • pp.35-44
    • /
    • 2016
  • Purpose: This study is focus on investigation of user's spontaneous behavior in the public space of ward where chronic patients are hospitalized. Methods: The notion and necessity of social healing environment is analyzed by literature review. User's location and behaviour are investigated for analyzing behavior by visiting the six wards. Results: The result 1) Stay is main behavior of users. 2) The frequency of stay is high in the place where are planned as the dayroom, the program room and the balcony. 3) In the corridor, the users are staying around court and single side corridor. And the users who are staying in the ward planned middle corridor and double corridor are spreaded all over the corridor. As the result of the analysis of correlation between frequency of user for stay and area of public space, 4) The area of the dayroom, the program room and the balcony is bigger, the frequency of users are higher. 5) There is no correlation between area of corridor and frequency of users. 6) When the density of user is highest in the place for stay, one person occupied $1.96m^2$. Implications: Hereafter the public space, which social healing environment is considered, is planned, this study could suggest the directions of architectural planning about area.

A Study on the Management Satisfaction to Cook (중간관리자와 조리사에 대한 만족도의 관련성에 관한 연구)

  • 진양호;김숙희
    • Culinary science and hospitality research
    • /
    • v.3
    • /
    • pp.83-122
    • /
    • 1997
  • The purpose of this study is to inquire management satisfaction factors of cook, and to grope for the correlation of career, number of cook, income, and education. To attain the purpose of this study, questionnaire was developed through pilot test. Questionnaire scale was adopted 5 point. The SPSS package was utilized for the analyses of questionnaire. The method was Frequency analysis and Chi Square analysis. The results obtained from the above data-based analysis are concentrated on management satisfaction to cook, and management recruiting method.

  • PDF

A study on the correlation between self-perceived oral health status and periodontal diseases in elderly Koreans (한국 노인의 본인인지 구강건강상태와 치주질환 관련성)

  • Jung, Eun-Seo;Lee, Kyeong-Hee
    • Journal of Korean society of Dental Hygiene
    • /
    • v.17 no.6
    • /
    • pp.1135-1145
    • /
    • 2017
  • Objectives: The objective of the study was to review the correlation between self-perceived oral health status and periodontal diseases in elderly Koreans, using data from the $6^{th}$ (2nd year) Korea National Health and Nutrition Examination Survey (2014). Methods: The subjects for this study were a total of 1,454 elderly people aged 65 years or older who responded to the health questionnaires of the $6^{th}$ (2nd year) Korea National Health and Nutrition Examination Survey conducted in 2014. Their general characteristics were analyzed using frequency analysis, while a cross-tabulation analysis (${\chi}^2-test$) was performed to understand the correlation with periodontal diseases. To clarify any effect of self-perceived oral health status on periodontal diseases, the selected variables were controlled and subsequently analyzed according to the logistic regression analysis. Results: In terms of the difference between elderly people with periodontal disease and those without periodontal disease, higher prevalence rates of periodontal diseases were found in women, those of younger age, those with lower educational and income levels, those with poorer subjective oral health status, those in the presence of chewing discomfort, those who had a toothbrushing frequency of twice per day, and/or those who had received no oral examination over the previous one year. Regarding the effect of self-perceived oral health status on periodontal diseases, 1.78-fold and 1.74-fold higher prevalence rates of periodontal diseases were shown with poorer subjective oral health status and in the presence of chewing discomfort, respectively. Conclusions: Based upon the results above, it is considered that a better understanding of self-perceived oral health status is necessary for a healthy life of the elderly. Furthermore, constant relevant studies and effective prevention programs intended to moderate the progress of or prevent periodontal diseases in the elderly in communities should be performed and implemented for the sake of better quality of life and oral health.

Prediction of Deficiency Pattern in Diabetic Patients Using Multi-frequency Bioimpedance Resistance (다주파수 생체임피던스 저항을 이용한 당뇨병 환자의 허증 변증 예측)

  • Kim, Kahye;Kim, Seul Gee;Cha, Jiyun;Yoo, Ho-Ryong;Kim, Jaeuk U.
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.36 no.3
    • /
    • pp.94-99
    • /
    • 2022
  • The discovery of biomarkers related to pattern identification (PI), the core diagnostic theory of Korean medicine (KM), is one of the methods that can provide objective and reliable evidence by applying PI to clinical practice. In this study, 40 diabetic patients and 41 healthy control subjects recruited from the Korean medicine clinic were examined to determine the human electrical response related to the deficiency pattern, a representative pattern of diabetes. Qi-Blood-Yin-Yang deficiency pattern scores, which are representative deficiency patterns for diabetes mellitus, were obtained through a questionnaire with verified reliability and validity, and the human electrical response was measured non-invasively using a bioimpedance meter. In ANCOVA analysis using gender as a covariate, the 5 kHz frequency resistance and 5-250 kHz frequency reactance were significantly lower in the diabetic group than in non-diabetic control group. In addition, the multiple regression analysis showed a positive correlation (R2=0.11~0.19) between the Yang deficiency pattern score and resistance value for the diabetic group; the correlation was higher at higher frequencies of 50kHz (R2=0.18) and 250kHz (R2=0.19) compared to 5kHz(R2=0.11). In contrast, there was no such significant association in the control group. It implies that bioimpedance resistance measured at finite frequencies may be useful in predicting Yang deficiency, which is closely related to diabetic complications by reflecting the decrease in body water content and metabolism. In the future, large-scale planned clinical studies will be needed to identify biomarkers associated with different types of PI in diabetes.

Wavelet-based automatic identification method of axle distribution information

  • Wang, Ning-Bo;Ren, Wei-Xin;Chen, Zhi-Wei
    • Structural Engineering and Mechanics
    • /
    • v.63 no.6
    • /
    • pp.761-769
    • /
    • 2017
  • Accurately extracting the axle distribution information of a passing vehicle from bridge dynamic responses experiences a key and challenging step in non-pavement bridge weigh-in-motion (BWIM). In this article, the wavelet transformation is adopted and the wavelet coefficient curve is used as a substitute for dynamic response. The driving frequency is introduced and expanded to multi-axle vehicle, and the wavelet coefficient curve on specific scale corresponding to the driving frequency is confirmed to contain obvious axle information. On this basis, an automatic method for axle distribution information identification is proposed. The specific wavelet scale can be obtained through iterative computing, and the false peaks due to bridge vibration can be eliminated through cross-correlation analysis of the wavelet coefficients of two measure points. The integrand function that corresponds to the maximum value of the cross-correlation function is used to identify the peaks caused by axles. A numerical application of the proposed axle information identification method is carried out. Numerical results demonstrate that this method acquires precise axle information from the responses of an axle-insensitive structure (e.g., girder) and decreases the requirement of sensitivity structure of BWIM. Finally, an experimental study on a full-scale simply supported bridge is also conducted to verify the effectiveness of this method.

Survey of the correlation between work injuries and job satisfaction in Logistics Center and ways to improve work satisfaction (물류센터 작업질환과 직무만족간 상관성 조사 및 개선방안)

  • Kim, Ki-Hong;Shin, Seung-Jun;An, Kyui-In;Nam, Seung-Don;Kang, Kyung-Sik
    • Journal of the Korea Safety Management & Science
    • /
    • v.13 no.4
    • /
    • pp.25-33
    • /
    • 2011
  • Workers in logistics centers also are exposed to serious musculoskeletal disorders the same as workers in general manufacturing due to operating forklifts and other labor duties. The frequency of these work related injuries decreases, workers' job satisfaction In addition, it causes many employees questioning a job change, which is regarded as the primary factor which drops the productivity. In this paper, we conducted a survey ti perceive the correlation between work related injuries in the fields of distribution centers and job satisfaction. Furthermore we made statistical analysis with our findings. The results of our analysis showed that the frequency of work related injuries due to workers' repetitive loading and unloading work is the primary factor which lowers job satisfaction. In order to improve aforementioned problem we propose first of all loading and unloading on pallet basis, second of all automation and computerization of logistics systems, and third of all ensurinf sufficient break time.

Mixed Noise Cancellation by Independent Vector Analysis and Frequency Band Beamforming Algorithm in 4-channel Environments (4채널 환경에서 독립벡터분석 및 주파수대역 빔형성 알고리즘에 의한 혼합잡음제거)

  • Choi, Jae-Seung
    • The Journal of the Korea institute of electronic communication sciences
    • /
    • v.14 no.5
    • /
    • pp.811-816
    • /
    • 2019
  • This paper first proposes a technique to separate clean speech signals and mixed noise signals by using an independent vector analysis algorithm of frequency band for 4 channel speech source signals with a noise. An improved output speech signal from the proposed independent vector analysis algorithm is obtained by using the cross-correlation between the signal outputs from the frequency domain delay-sum beamforming and the output signals separated from the proposed independent vector analysis algorithm. In the experiments, the proposed algorithm improves the maximum SNRs of 10.90dB and the segmental SNRs of 10.02dB compared with the frequency domain delay-sum beamforming algorithm for the input mixed noise speeches with 0dB and -5dB SNRs including white noise, respectively. Therefore, it can be seen from this experiment and consideration that the speech quality of this proposed algorithm is improved compared to the frequency domain delay-sum beamforming algorithm.