• 제목/요약/키워드: frequency and correlation analysis

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주파수분석법에 의한 치매환자와 정상인의 뇌파특성 비교 (Comparison of EEG Characteristics between Dementia Patient and Normal Person Using Frequency Analysis Method)

  • 장윤석;박규칠;한동욱
    • 한국전자통신학회논문지
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    • 제9권5호
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    • pp.595-600
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    • 2014
  • 요즘 우리 사회는 급속히 고령화 사회로 변화되고 있다. 고령화 사회에서는 치매에 대하여 잘 아는 것이 매우 중요한 일이다. 따라서 본 연구는 기본적으로 치매환자로부터 측정한 EEG 신호의 특성을 파악하는 것을 목표로 한다. 먼저 그것을 위하여 치매환자와 정상인의 EEG 특성을 구분하기 위하여 두 그룹의 자발 EEG 신호를 분석하였다. EEG 신호는 16개의 전극으로 계측하였고, 그 신호들은 주파수대역으로 분류하여 분석하였다. 보다 선명한 EEG 신호로 처리하기 위해서는 2개의 채널 간에 상호상관함수를 적용하였다. 그 결과, 치매환자와 정상인의 EEG 신호의 특성은 분명히 다르다는 사실을 확인할 수 있었다.

한국농수산대학 신입생 자기소개서의 텍스트 마이닝과 연관규칙 분석 (1) (Text Mining and Association Rules Analysis to a Self-Introduction Letter of Freshman at Korea National College of Agricultural and Fisheries (1))

  • 주진수;이소영;김종숙;신용광;박노복
    • 현장농수산연구지
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    • 제22권1호
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    • pp.113-129
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    • 2020
  • 본 연구는 2020년 한농대 입학생의 비정형 텍스트인 자소서에서 의미 있는 정보 혹은 규칙을 추출하기 위하여 고교 재학 중 '학업 및 학습경험'과 '교내 활동'을 기술한 두 개 문항에 대하여 텍스트 마이닝에 의한 토픽 분석과 연관성 분석을 하였다. 모집 전형을 구분하지 않은 텍스트 마이닝 분석 결과에서 '학업 및 학습 경험' 항목과 관련된 주요 키워드는 '공부', '생각', '노력', '문제', '친구' 등의 순으로 많이 나타났으며, '교내 활동' 항목과 관련된 주요 키워드는 '활동', '생각', '친구', '동아리', '학교' 등의 순으로 빈도가 높게 나타났다. 그러나 도시 인재 전형과 농수산 인재 전형 신입생들의 키워드 빈도 순위는 두 항목 모두 전형 특성에 따른 약간의 차이를 나타냈다. 빈도 분석에 결과는 빈도수 상위 50위까지의 키워드를 워드 클라우드로 시각화하여 키워드를 알기 쉽게 표현하였다. 연관 분석은 apriori() 함수를 사용하였으며 적정한 계산을 위하여 support(지지도)와 confidence(신뢰도)의 기준값을 항목별로 설정하였다. 먼저 '학업' 항목에 대한 연관 규칙은 46개를 추출하였으며, 그 가운데 {공부} => {생각}, {성적} => {공부} 및 {과목} => {공부} 등의 규칙에서 높은 연관성을 볼 수 있었다. 이 규칙을 바탕으로 매개체 역할의 키워드를 평가하는 관계 중심성 평가와 노드에 연결된 edge의 수에 따라 중요도를 파악하는 연결 중심성 평가에서는 '생각', '공부', '노력', '시간' 등의 키워드가 중심적인 역할을 하는 정보를 획득하였다. 다음으로 '교내 활동' 항목에서는 45개의 연관 규칙을 생성하여 {활동} => {생각}, {동아리} => {활동} 등의 규칙에서 높은 연관성을 볼 수 있었으며, 관계 중심성 평가와 연결 중심성 평가에서는 '생각', '활동', '학교', '시간', '친구' 등의 키워드가 중심 키워드라는 결과를 얻었다. 다음 연구에서는 자소서의 나머지 두 개의 문항 '배려·나눔·협력·갈등관리' 항목과 한농대 '지원동기와 향후 진로계획' 항목을 분석한다. 분석에는 '키워드의 빈도'에 '문서 빈도의 역수'를 곱하여 주로 다량의 문서에서 핵심어를 추출하는 TF-IDF(Term Frequency-Inverse Document Frequency) 분석을 추가한다.

로하스 의식이 로하스 큐티클 관리에 미치는 영향 (A Study on the Influences of LOHAS Consciousness on LOHAS Cuticle Management)

  • 조윤희;김순심
    • 한국의상디자인학회지
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    • 제14권2호
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    • pp.215-227
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    • 2012
  • This study aims to analyze the influences of LOHAS cuticle management, which based on LOHAS consciousness among customers using nail art shops and removes only Cuticle layer without Eponychium, on the preference and expected value of service quality. Further, it tackles how above related variables have important bearing on reuse intention. A survey was conducted only with customers over the age of 20 in Seoul, Daejeon and Daegu areas in terms of LOHAS consciousness. For the collected 389 data, frequency analysis, t-test, ANOVA, correlation analysis and multiple regression analysis were carried out by using SPSS 18.0 Version statistical package. The results are as follows. First, according to the results, it shows high positive correlation between LOHAS cuticle management based on the consciousness of LOHAS, and LOHAS cuticle management preference, tendency and willingness to transfer toward it. Second. it is proven that LOHAS consciousness tend to be possessed in older age groups, married and a professional employee layers and this LOHAS motivated groups showed high LOHAS cuticle management preference, inclination and intention of a change in management. Lastly, the reuse intention is mostly affected by experience and preference of LOHAS cuticle management. There is negative correlation between reuse intention and experience in blooding and pain during care service. Higher interest in preference of LOHAS cuticle management has highly influenced positive link with the repurchase intention.

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응급구조학전공 학생의 병원 임상실습 만족도에 영향을 미치는 요인 (Influencing Factors on the Satisfaction of the Paramedic Students in Clinical Training)

  • 박소미;최은숙
    • 한국응급구조학회지
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    • 제16권1호
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    • pp.91-101
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    • 2012
  • Purpose: This study aims to assess the influencing factors on the level of satisfaction with clinical training and to provide basic data for more efficient clinical training. Method: The study was conducted on 402 paramedic students who have experienced clinical training from September 6 until October 12 in 2011. The questionnaires consisted of 40 questions. We used SPSS 18.0 frequency analysis, technical statistics, t-test, ANOVA, Pearson's correlation coefficients and multiple regression analysis. Result: 1. The level of satisfaction with clinical training showed significant difference between the frequency (F=8.837, p=.000) and clinical training managers (F=5.418, p=.001). 2. The level of satisfaction with clinical training showed the strongest positive correlation with the satisfaction of clinical training hospitals (r=.694, p=.000). 3. Multiple regression analysis revealed the most powerful predictor for satisfaction with clinical training was the satisfaction level of clinical training hospitals(48.2%) and the frequency of clinical training experiences(.8%), the preparation before the clinical training(5.4%), the total duration of clinical training(.7%), and the satisfaction of emergency department education(1.0%). These five variables accounted for 56.1% of the satisfaction of clinical training among paramedic students. Conclusion: As student's satisfaction of the clinical training increases, the quality of paramedics is expected to improve in the future. As a result, the future paramedics can be nurtured to be highly skilled in on-the-scene emergency situations after graduation.

승용차의 진동해석모델 개발 (Development of the Vibration Analysis Model of Passenger Car)

  • 권순기
    • 한국소음진동공학회논문집
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    • 제21권4호
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    • pp.291-298
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    • 2011
  • According to the developments of automobile industry, the technology to enhance noise, vibration and harshness(NVH) performance has been studying in a point of view of ride comfort and quietness. Especially the use of computer aided engineering(CAE) simulation tools such as finite element(FE) analysis allows engineers to efficiently evaluate NVH performance. This paper presents the method to bulid FE models for full vehicle including engine, transmission. suspension and steering system, also to evaluate vibration performance of full vehicle. The full vehicle model, which is discussed, is correlated with the result of the frequency response measurement in the case of the car shake performance for high speed driving.

스플리터 단면형상변화에 따른 플라스틱 유량계의 유동진동특성 (Fluidic oscillation characteristics of plastic flow meter with the variation of cross-sectional shape of splitters)

  • 이성희
    • Design & Manufacturing
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    • 제15권2호
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    • pp.56-62
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    • 2021
  • In this study, design technology of a non-mechanical flow meter using fluidic oscillation generated during the fluid flow in the chamber was investigated. To with respect to design a splitter, which is the most important factor in fluid oscillation, a transient flow simulation analysis was performed for three types of shapes and changes in inlet flow velocity. The oscillation characteristics with respect to the time in each case were compared, and it was confirmed that the SM03 model was the best among the presented models. In addition, the FFT analysis of the fluid oscillation results for the SM03 model was used to obtain a linear correlation between the flow velocity change and the maximum frequency, and a frequency of 20.957 (Hz/m/s) per unit flow velocity was obtained. Finally, injection molding simulation and molding experiment of the chamber with the designed splitter were performed.

Analysis of Relationship between Construction Accidents and Particulate Matter using Big Data

  • Lee, Minsu;Jeong, Jaewook;Jeong, Jaemin;Lee, Jaehyun
    • 국제학술발표논문집
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    • The 9th International Conference on Construction Engineering and Project Management
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    • pp.128-135
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    • 2022
  • Because construction work is conducted outdoors, construction workers are affected by harmful environmental factor. Especially, Particulate Matter (PM10) is one of the harmful environmental factors with a diameter of 10㎍/m3 or less. When PM10 is inhaled by human, it can cause fatal impact on the human. Contrary to the various analyses of health impact on PM10, the research on the relationship between construction accidents and PM10 are few. Therefore, this study aims to conduct the relative frequency analysis which find out the correlation between construction accidents and PM10, and the modified PM10 grade is suggested to expect accidents probability caused by PM10 in the construction industry. This study is conducted by four steps. i) Establishment of the database; ii) Classification of data; iii) Analysis of the Relative Frequency of accidents in the construction industry by PM10 concentration; iv) Modified PM10 groups to classify the impact of PM10 on accident. In terms of frequency analysis, the most accidents were occurred in the average concentration of PM10 (32㎍/m3). However, we found that the relative frequency of accident was increased as the concentration of PM10 increased. This means the higher PM10 concentration can cause more accidents during construction. In addition, PM10 concentration was divided as 6 groups by the WHO, but the modified PM10 grade by the relative frequency on accident was suggested as 3 groups.

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A clinical study of alveolar bone quality using the fractal dimension and the implant stability quotient

  • Lee, Dae-Hyun;Ku, Young;Rhyu, In-Chul;Hong, Jeong-Ug;Lee, Cheol-Woo;Heo, Min-Suk;Huh, Kyung-Hoe
    • Journal of Periodontal and Implant Science
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    • 제40권1호
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    • pp.19-24
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    • 2010
  • Purpose: It has been suggested that primary implant stability plays an essential role in successful osseointegration. Resonance frequency analysis (RFA) is widely used to measure the initial stability of implants because it provides superior reproducibility and non-invasiveness. The purpose of this study is to investigate whether the fractal dimension from the panoramic radiograph is related to the primary stability of the implant as represented by RFA. Methods: This study included 22 patients who underwent dental implant installation at the Department of Periodontology of Seoul National University Dental Hospital. Morphometric analysis and fractal analysis of the bone trabecular pattern were performed using panoramic radiographs, and the implant stability quotient (ISQ) values were measured after implant installation using RFA. The radiographs of 52 implant sites were analyzed, and the ISQ values were compared with the results from the morphometric analysis and fractal analysis. Results: The Pearson correlation showed a linear correlation between the ISQ values of RFA and the parameters of morphometric analysis but not of statistical significance. The fractal dimension had a linear correlation that was statistically significant. The correlation was more pronounced in the mandible. Conclusions: In conclusion, we suggest that the fractal dimension acquired from the panoramic radiograph may be a useful predictor of the initial stability of dental implants.

산부의 분만 자신감 결정요인에 관한 연구 (Factors Influencing Self Confidence during Delivery in Laboring Women)

  • 이미경
    • 여성건강간호학회지
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    • 제11권1호
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    • pp.20-26
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    • 2005
  • Purpose: The purpose of this study was to understand self confidence during delivery in laboring women and to identify the factors influencing self confidence for delivery. Method: The participants of the study were 166 women who were admitted to a delivery room at C hospital in Seoul from July 1 to October 31, 2002. Data was collected using a structured questionnaire, self confidence scale, anxiety scale, knowledge of childbirth scale and graphic rating scale. The data was analyzed by the SPSS PC+ program. For the analysis of collected data, frequency analysis, Pearson's correlation, multiple linear regression analysis and stepwise selection method was used. Result: Self confidence during delivery had negative correlation coefficients with anxiety, and positive correlation coefficients with endurance of pain, husband support during pregnancy, age and parity. Anxiety was the highest factor influencing self confidence for delivery(40.0%). Endurance of pain, husband support during pregnancy and age accounted for 49.0% of self confidence in laboring women. Conclusion: The factors influencing self confidence during delivery were anxiety, endurance to pain, husband support during pregnancy and age. Further studies need to be done to identify interventions for overcoming on anxiety, promoting endurance of pain, and increasing husband support during pregnancy.

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초등학생의 인터넷 중독과 VDT 증후군 및 건강행위 간의 관련성 (The Relationship with Internet Addiction, VDT Syndrome and Health Behavior of Elementary School Students)

  • 이경란;황미혜
    • 한국학교ㆍ지역보건교육학회지
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    • 제9권2호
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    • pp.65-80
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    • 2008
  • Objectives: To identify the relationship between the internet addition of elementary school students, and their health behavior and VDT syndrome, and thereby to detect the impact of internet addiction on the health behavior of elementary school students, to get the basic information necessary to develop a prevention program for internet addiction and to plan for VDT syndrome prevention program. Methods: We conducted this study during the period from jun 27, 2007 through July 8, 2007. The subjects of this study were 416 children whose grades were in 4th through 6th grades of elementary schools located in the city A in Kyung Pook Providence. Data were obtained from self-rating questionnaires. The questionnaires were composed of Korean Internet Addiction Self-examination on Internet Use Patterns (K-scale), Health Behavior Profile, VDT Syndrome, and general characteristics. We used t-test, AVOVA with Ducan method for Post-hoc comparison in means comparison between groups, $X^2$-test for frequency analysis and Pearson's correlation coefficient. We used SPSS/PC(12.0 ver) program and the LISREL 8.53 Win program for covariance structural analysis. Results: Major results were as follows. 1. The internet addiction propensity distribution based on the distribution of scores were investigated according to the self diagnosis scale on internet addiction. 6.5% of them were high risk user group, 14.4% were potential risk users and 79.1% of them were common user groups. 2. Internet addictions by sex, internet use duration, frequency (days/week), time(hours/day), purpose, position, brightness of internet, attitude of parents and frequency of conversation of family members were statistically significant(p<0.01). 3. There was a statistically significant difference in VDT syndrome according to internet addiction groups(p<0.001) besides ocular symptoms, dry mouth and GI troubles. 4. The health behavior score was the lowest in high risk user group(p<0.001). There were significant differences between internet addiction groups in personal hygiene and habits of daily living(p<.002), the prevention of accidents(p<.002), the practice concerned with the prevention of infectious disease(p=.002), and mental health(p<.001). 5. There was also a significant negative correlation between internal addiction and health profile(r=-0.365, p<0.01) and a significant positive correlation between internal addiction and VDT syndrome(r=0.331, p<0.01). 6. As the result of structural model analysis, internet use time(/day), days of internet use(/1week), conversation frequency among family members, degree of brightness of internet use had significant direct effects on internet addiction. Conclusions: The results will help the development of an effective intervention program for the prevention and treatment of internal addiction by clarifying the effect of the internal addiction upon elementary school students' VDT syndrome and health behavior.

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