• 제목/요약/키워드: frequency and correlation analysis

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식이섭취조사방법과 조사일수에 따른 한국 젊은 여성의 영양소 섭취 수준의 비교 (Comparison of the Levels of Nutrient Intakes by Different Dietary Methods and Days of Dietary Studies Among Young Females in Korea)

  • 오세영
    • Journal of Nutrition and Health
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    • 제29권9호
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    • pp.1021-1027
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    • 1996
  • This study examined the patterns of nutrient intakes measured by 1-, 3-, 7-day recalls and records as well as food frequency questionnaire among 59 females volunteers enrolled in the university in Seoul, Korea. Over a 4 month period, a modified Willett food frequency questionnaire was administered once, and a 24-hour dietary recall was conducted 12 times and a weighted dietary record 14 times. From these 12 recalls and 14 records, 1-, 3-, 7-day data were randomly selected. For energy and 11 nutrients, group mean intakes derived from food frequency questionnaire were higher than from recalls and records. Group mean intakes from recalls and records showed little differences depending on days of dietary studies and dietary methods. Measures of agreement were calculated by weighted kappa and intraclass correlation coefficient values calculated for quintile categories while comparing to the results of 26 days recalls and records. Weighted kappa values ranged from 0.11 for riboflavin to 0.36 for vitamin C for and 1-day recall, and from 0.21 for iron to 0.31 for energy for the 1-day record. Weighted kappa values were increased as the number of days of dietary studies increased (0.34-0.57 for the 3-day recalls, 0.27-0.50 for the 3-day records, 0.50-0.68 for the 7-day recalls, and 0.50-0.65 for the 7-day records). Weighted kappa values for food frequency questionnaire were higher than the 1-day data, but lower than the 3-and-7day data(0.34 for energy, 0.31 for iron and 0.22 for vitamin C). Intraclass correlation coefficients ranged from 0.21 for vitamin A to 0.57 for calcium. The degrees of agreement by different methods and days of dietary study are lower in our study compared to agreement by different methods and days of dietary study are lower in our study compared to those in previously published studies for Western populations, partly due to the differences of data analysis methods as well as of dietary patterns between those samples and ours.

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781MHz 대역에서 안테나 상관도를 고려한 개선된 MIMO 채널 특성 분석 방법 (Enhanced Analysis Method of MIMO Channel Characteristics with Antenna Correlation at 781MHz)

  • 정명원;정영준;백정기
    • 한국인터넷방송통신학회논문지
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    • 제13권3호
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    • pp.17-24
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    • 2013
  • 본 논문은 781MHz 대역에서 안테나 상관도를 고려한 MIMO 채널 측정을 통해, 측정 데이터를 분석하고 채널 특성을 도출하였다. 상기 주파수 대역은 DTV 시스템에서 이동통신 주파수로 할당이 예정된 대역이다. 781MHz 주파수 대역은 900MHz 이동통신 시스템의 채널특성이 일정부분 유사하지만, 상당히 다른 부분이 있음을 기존 연구를 통해 증명하였다. 또한, 안테나의 상관도를 고려할 경우 신호전달 과정에 대한 보다 정확한 예측을 위해서는 채널 특성 연구가 필요하다. 기존 DTV 방송과 혼신을 피하기 위하여 측정은 제주도 인근 도심지역에서 채널사운더와 $4{\times}4$ 안테나로 채널특성을 측정하였다. 측정된 데이터를 바탕으로 도심지역에서 안테나 상관도를 고려한 채널특성을 도출하였다.

한국 성인의 식사 빈도에 따른 심혈관대사질환 위험도와 식사 질의 매개효과 : 국민건강영양조사 제7기 자료 (Mediating Effects of Diet Quality between Meal Frequency and Cardiometabolic Risk among Korean Adults: Data from the 7th Korea National Health and Nutrition Examination Survey (KNHNES))

  • 조유미;이경숙
    • 중환자간호학회지
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    • 제16권2호
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    • pp.67-80
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    • 2023
  • Purpose : The 2020 Dietary Guidelines Advisory Committee specifically noted that meal frequency is associated with risks for cardiovascular disease, type 2 diabetes, and all-cause mortality, although the current evidence on meal frequency is conflicting. As meal frequency itself is affected by various factors, the aim of the study was not only to examine its relationships with cardiometabolic risk but also to identify the mediating effects of dietary quality. Methods : This study used a descriptive correlational design. In all 8,141 healthy adults participated in the study. Measurements included meal frequency, cardiometabolic risk, and diet quality. Data were analyzed using descriptive statistics, Pearson's correlation coefficient analysis, and process macro bootstrapping model 4. Results : The meal frequency was 3.52±0.61 times per day, the risk of cardiovascular metabolic diseases was 0.01±0.61 points, and the diet quality was 62.08±13.87 points. In mediation analysis, the effect of meal frequency on cardiometabolic risk score was completely mediated by diet quality. Conclusion : Improved diet quality in healthy adults should be considered when designing meal frequency interventions aimed at reducing their cardiometabolic risk, as the effect of meal frequency support on cardiometabolic risk was found to be mediated by diet quality.

유아의 구강보건관리에 영향을 미치는 요인에 관한 연구 (A Study on the Factors which affect the Oral Health Care of Infants)

  • 김설악
    • 한국학교보건학회지
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    • 제8권2호
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    • pp.315-326
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    • 1995
  • This study was performed to find variables which affect oral health care of infants. The subjects were 439 infants and their mothers who live in suburban area. Oral examinations for the infants were conducted and the questionnairs were given to infants' mothers. Toothbrushing frequency, oral hygiene score, the percentage of filled teeth among decayed teeth, and dental treatment experience of infants were used as dependent variable, respectively. Demographic, socio-economic variables and the other variables which might affect oral health care of infants were used as independent variables. Correlation analysis and analysis of variance were used for the independent variables of toothbrushing frequency, oral hygiene score, and the percentage of filled teeth among decayed teeth of infant. Chi-Square and Student's t-test were used for the dependent variables of dental treatment experience of infant. The obtained results were as follows; 1. Toothbrushing frequency of mother and internal locus of oral control of mother were the factors which affect toothbrusing frequency of infants. 2. Oral health belief of mother was the factor which affect oral hygiene score of infants. 3. Age of infant was the factor which affect the percentage of filled teeth among decayed teeth. 4. Age of infant and educational level of infant's mother were the factors which affect the infants' consumption of dental treatment.

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슈트용 직물의 스치는 소리와 물성간의 관계 (Relationship between Rustling Sounds and Physical Properties of Suiting fabrics)

  • 조길수;이은주
    • 한국감성과학회:학술대회논문집
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    • 한국감성과학회 1999년도 춘계학술발표논문집 논문집
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    • pp.271-276
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    • 1999
  • This study was carried out to investigate the relationship between sound color and physical propertiessuiting fabrics. Rustling sounds of 23 suiting fabrics by sound generator developed for this study were recorded and analysed through FFT analysis. Three sound color factor(ΔL Δf. LPT) were obtained.Physical properties of specimens were measured by KES-FB. Level range(L) showed significant correlation with tensile resilience(RT) and thickness (T). Frequency difference(Δf) showed significant correlation with tensile linearity(LT), shear properties(G, 2HG, 2HG5), compressional energy(WC), and weight(W). Total sound pressure (LPT) showed significant correlation with elongation at maximum load (EM), tensile linearity(LY), and tesile energy(WT). By stepwise regression LPT was found to be explained by EM, MIU, RC, LT significantly.

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Wavenumber correlation analysis of satellite magnetometer observations

  • Kim, Jeong-Woo;Kim, Won-Kyun;Kim, Hye-Yun
    • 대한자원환경지질학회:학술대회논문집
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    • 대한자원환경지질학회 2000년도 춘계공동학술발표회
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    • pp.311-313
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    • 2000
  • Identifying anomaly correlations between data sets is the basis for rationalizing geopotenial interpretation and theory. A procedure between the two or more geopotential data sets. Anomaly features that show direct, inverse, or no correlationsbetween the data may be separated by applying filters in the frequency domains of the data sets. The correlation filter passes or rejects wavenumbers between co-registered data sets based on the correlation coefficient between common wavenumbers as given by the cosine of their phase difference. This study includes as example of Magsat magnetic anomaly profile that illustrates the usefulness of the procedure for extracting correlative features between the sets.

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가정식사 대용식(HMR) 제품 유형별 재구매 의도와 소비자 태도 구성개념간의 구조적 관련성 검증 (The Structural Correlation between Consumer's Attitudes and Intention of Repurchase of Home Meal Replacement (HMR) according to the Product Categories)

  • 정라나;이해영;양일선
    • 대한지역사회영양학회지
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    • 제12권3호
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    • pp.344-351
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    • 2007
  • The purposes of this study were to analyze the consumer inclination to convenience towards HMR in order to verify the structural correlation of the actual state of consumption, and to analyze consequently, the direct or indirect effects among 'frequency of using,' 'preference', 'satisfaction', and 'intention to repurchase'. The subjects were adults in their twenties or older who had used HMRs and lived in Seoul and Gyeonggi Province in Korea. Random sampling of 550 subjects, who were distributed a questionnaire from March 12 to 30, 2005. A total of 451 questionnaires were returned (the return rates were 82%). The main results of this study were as follows : Regarding the types of HMR, 'Ready to eat' had higher preference (3.31), satisfaction (3.33) and 'intention to purchase it again' (3.38) than those of 'Ready to heat' and 'Ready to end-cook.' Consumer inclination to convenience towards HMR was analyzed in order to verify the structural correlation of the actual state of consumption, and consequently, the direct or indirect effects among 'frequency of using,' 'preference', 'satisfaction', and 'intention to repurchase' were analyzed. The gross effect of 'frequency of using' on 'intention to repurchase' was 0.435, the gross effect of preference on 'intention to purchase it again' was 0.659, and the gross effect of satisfaction on 'intention to purchase it again' was 0.772 for 'Ready to eat.' The gross effect of 'frequency of using' on 'intention to repurchase' was 0.448, the gross effect of preference on 'intention to repurchase' was 0.556, and the gross effect of satisfaction on 'intention to repurchase' was 0.654 for 'Ready to heat.' The gross effect of 'frequency of using' on 'intention to repurchase' was 0.432, the gross effect of preference on 'intention to repurchase' was 0.494, and the gross effect of satisfaction on 'intention to repurchase' was 0.608 for 'Ready to end-cook.' To summerize the above results, there was a difference of the structural correlation among component concepts of the actual state of consuming according to the criteria of HMR. Thus, it implied that differentiated sales strategies were needed according to the criteria of HMR.

부정합된 최대 상관값을 이용한 초기 동기 임계치 결정 기법 (Threshold detection technique for code acquisition using maximum mismatched correlation value)

  • 유영환;김종헌;강성철;강창언
    • 한국통신학회논문지
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    • 제21권7호
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    • pp.1803-1813
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    • 1996
  • This paper describes an automatic threshold decision using a maximum mismatched correlation value in the direct sequence spread spectrum (DS-SS) system. For received PN codes with different single-to-noise ratio (SNR), this scheme is able to detect a desired threshold value in the search mode, i.e. a maximum mismstched correlation value, so that value is utilized as a threshold for the verification mode. Performance of the proposed scheme in both the additive white gaussian noise (AWGN) and frequency-selective Rayleigh fading channels is analyzed through the Monte Carlo simulation. And hardware implementation of this scheme using a DSP processor is demonstrated. The proposed acquisition shceme is compared to the conventional constant threshold (CT) scheme, and significant improvement of performance is shown. Analysis of system performance in the verification mode is presented, and key quantities such as the false alarm probability and the detection probability are derived in a AWGN channel.

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종합병원 중간관리자의 역량군별 중요도 인식과 수행수준 차이 및 요인분석 (Analysis of the Factors and the Differences in the Awareness about the Capability Groups of the Mediator Manager in General Hospital and the Level of Performance)

  • 김희숙;조우현;김영훈;김태현
    • 한국병원경영학회지
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    • 제16권3호
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    • pp.92-114
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    • 2011
  • The study has its purpose on providing basic resource to enforce the capability of the middle managers by examining the level of performance and the level of awareness about the capabilities of the managers and by understanding the significance of the difference and the reasons for the differences. The source of the study was 195 survey questionnaires that were carried out to the managers of the 9 general hospitals and the method of the analysis was the frequency analysis, analysis of the credibility, matching to sample T-test, independent sample T-test, dispersion analysis, correlation analysis, and multiple linear regression analysis using accumulated variables. The followings are the main result of the study. First, the difference between the level of awareness about the capabilities and the level of performance of the mediator managers in general hospitals had high capability in change management. The following orders were: competence in achievement and behavior, competence in management, competence in recognition, competence in influence, competence in individual effectiveness, and competence in personal relationship service. Second, as the result of the relation analysis in order to understand the correlation between awareness and performance of the mediator managers, everything had significant positive correlation. In the study about the level of importance, the cognitive capability and the management capability had the highest correlation with the correlation number of 0.88. In the study about the level of performance, the cognitive capability, individual capability, and the management capability had the highest correlation with the correlation variable number of 0.79. Third, as the result of studying the reason for the difference between the level of the awareness capability and the level of the performance, lack of the support recognition compensation in the organization level, inappropriate work environment, limit in the regulation were found as the highest reason in the order. As the result of the study, it was concluded that the creation of the efficient capability estimation model and the securement of the system that estimate the capability of the managers should be carried out in order to enforce the capability of the mediator managers in general hospitals.

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Harmonics(배음)와 Formant Bandwidth(포먼트 폭)를 이용한 음성특성(音聲特性)과 사상체질간(四象體質間)의 상관성(相關性) 연구(硏究) (A Study on the Correlation Between Sasang Constitution and Sound Characteristics Used Harmonics and Formant Bandwidth)

  • 박성진;김달래
    • 사상체질의학회지
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    • 제16권1호
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    • pp.61-73
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    • 2004
  • This study was prepared to investigate the correlation between Sasang constitutional groups and voice characteristics using voice analysis system(in this study, CSL). I focused on the voice characteristics in terms of harmonics, Formant frequency and Formant Bandwidth. The subjects were 71 males. I classified them into three groups, that is Soeumin group, Soyangin group and Taeumin group. The classification method of Constitution used two ways, QSCCII(Questionnarie for the Sasang Constitution Classification II) and Interview with a specialist in Sasang Constitution. So 71 people were categorized into 31 Soeumin(people), 18 Soyangin(people) and 22 Taeumin(people). Pitch is approximately similar to the fundamental frequency(F0) in voices. Shimmer in dB gives an evaluation of the period-to-period variability of the peak-to-peak amplitude within the analyzed voice sample. FFT(Fast Fourier Transform) method in CSL can display sampled voices into harmonics. H1 is the first peak and h2 is the second peak in the harmonics. The amplitude difference of h1 and h2(h1-h2) can be explained as the speaker's phonation type, And Formant frequency and bandwidth can be explained as the speaker's vocal tract. So I checked the harmonics and Formant frequency and Bandwidth as the voice parameters. First I have captured /e/ voices from all subjects using microphone. And then I analyzed /e/ voices with CSL. Power Spectrum and Formant History is the menu in the CSL which can display harmonics and Formant frequency and bandwidth. The results about the correlation between Sasang Constitutional Groups and voice parameters are as follows; 1. There is no significant amplitude difference of harmonics(h1-h2) among three groups. 2. There is the significant difference between Soeumin Group and Soyangin Group in Formant Frequency 1 and Formant Bandwidth 1(p<0.05). Any other parameters have no significance. I assume that Soyangin Group has clearer and brighter voice than Soeumin Group according to the Formant Bandwidth difference. And I think its result has coincidence with the context of "Dongyi Suse Bowon" and "Sasangimhejinam".

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