• 천문학회보
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• 제39권2호
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• pp.83.2-83.2
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• 2014

Flare and rotational variabilities induced by stellar activity are important for studying the effect of magnetic fields on the evolution of red dwarf stars. The level and frequency of magnetic activity in these stars have a different aspect at every moment of the observations due to the effect of age-rotation relation. The use of both tracers is thus essential to have a relatively homogeneous set of stellar activity data for statistical studies. The archival light curves and imaging data of the open cluster M37 taken by MMT 6.5m telescope were used for this work. In order to achieve much more accurate photometric precisions and also to make the most efficient use of the data, the entire imaging database were re-analyzed with our new time-series photometry technique and carefully calibration procedures. Based on the new light curves, we study, for the first time, a variety of aspects of those two variabilities in red dwarfs and their relation to magnetic activity. In this talk, we present all observational evidences that support the idea that the strength of magnetic activity is closely connected with the rotation rate of a star and its evolutionary status (age-activity-rotation paradigm). In conclusion, we suggest future directions to improve our understanding of stellar activity in cool stars with photometric time-series data.

• 한국학교보건학회지
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• 제31권3호
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• pp.196-202
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• 2018

Purpose: The purpose of this study was to analyze the relationship between physical activity and energy drinks consumption in Korean Adolescents. Methods: This study was a secondary data analysis using statistics from the 2017(13th) Korea Youth Risk Behavior Web-based Survey. The variables used in the study were physical activity, energy drinks consumption and socio-demographic characteristics such as gender, academic achievement, household economic status and weekly allowance. The data were analyzed by $x^2$ test and multinominal logistic regression and the results were presented in percentage. Results: As the number of days engaging in moderate and vigorous physical activities increased, the response that they consume energy drinks 'more than 5 times a week' also increased. The subjects who participated in a 'moderate' or 'high' level of moderate physical activity consumed 1.4 times more energy drinks than those who do not participate in physical activity. And the subjects who engaged in a 'low' or 'moderate' level of vigorous physical activity consumed about 1.3 times more energy drinks than those who don't work out. Conclusion: As the level and intensity of physical activity increased, the number and frequency of energy drinks consumption increased. The results of this study can be used as basic data for intervention programs to reduce energy drinks consumption and promote proper physical activity.

• Physical Therapy Rehabilitation Science
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• 제11권4호
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• pp.535-545
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• 2022

Objective: This study was conducted to identify predictive factors of physical activity in total hip arthroplasty patients, and to provide basic data for the developing physical activity promotion program for total hip arthroplasty patients. Design: Descriptive correlational research. Methods: Data were collected from August 2017 to May 2018. Surveys were distributed to 60 patients in a G university hospital located at J city, Gyeongsangnam-do. Data were analyzed by frequency, mean, standard deviation, t-test, ANOVA, Pearson's correlation coefficient, multiple regression analysis using SPSS 24 Win program. Results: The variables affecting the 4-week physical activity after discharge were age (β=.07), residence after discharge (β=-.22), cerebrovascular disease (β=-.13), mental and behavioural disease (β=-.11), taking antibiotic (β=-.26), walking ability (β=.41), nutritional status (β=.25), depression (β=.05). The eight variables accounted for 39.4% in the 4-week physical activity (F=4.49 p=.001). The variables affecting the 8-week physical activity after discharge were age (β=.06), waking ability (β=.34), nutritional status (β=.20), exercise self-efficacy (β=.05), depression (β=-.05). The six variables accounted for 28.0% in the 8-week physical activity (F=4.58, p<.001). Conclusions: The walking ability in discharge important to improve the physical activity, there is a need to develop an program to improve walking ability before discharge, in total hip arthroplasty. There is a need to develop a physical activity program to consistently participate in a community.

• 대한전기학회논문지:시스템및제어부문D
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• 제51권1호
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• pp.32-38
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• 2002

This paper describes a development of a portable physical activity monitoring system using two accelerometers to quantify physical activity. The system hardware consists of two piezoresistive accelerometers, amplifiers with gain of 30, lowpass filters with cut-off frequency of 15Hz, offset control circuits, one-chip microcontroller and flash memory card. In order to evaluate the performance of the system we acquired 3 channel data at 32 sample/sec from body-fixed accelerometers in chest and right upper leg. And then the acquired data were processed by MatLab on personal computer. We tried to distinguish not only fundamental actions which are steady-state activities such as standing, sitting, and lying but also dynamic activities with walking, up a stairway, down a stairway, and running. Five subjects participated the evaluation process which compare the video data with the measured data. As a result, the activity classification rate of 90.6% on average was obtained. Overall results showed that the steady-state activities could be classified from the low component of 3-axis acceleration signal and dynamic activities could be distinguished from frequency analysis using wavelet transform and FFT. Finally, we could find that this system can be applied to acquire and analyze the static and dynamic physical activity data.

• 실천공학교육논문지
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• 제16권4호
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• pp.577-585
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• 2024

This study analyzed the relationship between GPS-based physical activity patterns and mental health using Kaggle Student Life data. Data were collected over a 10-week period from 48 students at Dartmouth College through Android smartphones and included GPS, dark, and phone lock data, and measures such as the Patient Health Questionnaire-9 (PHQ-9), Loneliness Scale, the Positive and Negative Affect Schedule (PANAS), and Perceived Stress Scale. Using latitude and longitude data obtained from GPS measurements, various physical activity indicators were calculated, including the total distance traveled, average distance traveled, average distance traveled in the morning, average distance traveled in the afternoon, average distance traveled in the evening, and average distance traveled in the middle of the night. Pearson's correlation analysis was performed to explore the relationship between GPS-based physical activity patterns and mental health. The study results indicated a significant negative correlation between the average distance traveled in the afternoon and PHQ-9 scores. Results indicated that the higher the afternoon activity, the lower the depressive symptoms. There was a positive correlation be-tween the PANAS-Pos score and the average distance traveled in the evening, indicating that positive emotions tended to increase as evening activities increased. This finding suggests a relationship between physical activity at specific times and mental health.

• 대한안전경영과학회지
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• 제3권2호
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• pp.145-154
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• 2001

This paper deals with Activity Analysis Method that is important procedure in Activity Based Costing System Implementation. There are many existing Activity Analysis Method, for example Interview, Questionnaire, Specialist Discussion and Work Measurement. Activity Analysis Data gained through this method has high reliability but this method bring about high cost. In case that certain company needs a strategic costing system, Activity Analysis Method which has high reliability will be need. But, if companies want the costing system as a internal decision making tool only, they need to design the ABC system fast and cheaply. This paper explains that Activity Analysis using existing finn material is good alternatives. So, this paper show the feasibility of Activity Analysis using existing firm material with comparing between job description, job specification information and Activity Analysis information.

• International Journal of Advanced Culture Technology
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• 제10권4호
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• pp.361-368
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• 2022

This study seeks to determine the research trend of late adolescents by utilizing big data. Also, seek for research trends related to activity participation, treatment, and mediation to provide academic implications. For this process, gathered 1.000 academic papers and used TF-IDF analysis method, and the topic modeling based on co-occurrence word network analysis method LDA (Latent Dirichlet Allocation) to analyze. In conclusion this study conducted analysis of activity participation, treatment, and mediation of late adolescents by TF-IDF analysis method, co-occurrence word network analysis method, and topic modeling analysis based on LDA(Latent Dirichlet Allocation). The results were proposed through visualization, and carries significance as this study analyzed activity, treatment, mediation factors of late adolescents, and provides new analysis methods to figure out the basic materials of activity participation trends, treatment, and mediation of late adolescents.

• 한국도서관정보학회지
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• 제54권1호
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• pp.167-190
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• 2023

본 연구는 활동이론을 이론적 틀로 활용하여 연구데이터 큐레이션 모델을 분석한 문헌 연구로, 활동이론에서 사용하는 활동의 구성 요소들을 바탕으로 여러 연구데이터 큐레이션 모델을 분석했을 뿐만 아니라 연구데이터 큐레이션 활동을 수행하는데 있어서 도서관계에서 논의가 필요한 현안을 분석하였다. 그리고 이를 기반으로 새로운 연구데이터 큐레이션 개념 모델을 제안하였다. 본 연구는 기존에 제안된 5개의 디지털 큐레이션 생애주기모델이 어떻게 구성되어 있는지 분석하고 각각의 모델에서 산발적으로 제시되는 활동요인들을 분석하여 공통요인을 추출하고 새로운 모델로 통합하여 새로운 연구데이터 큐레이션 개념 모델을 제안하였다. 또한, 도서관 및 리포지토리에서 연구데이터 큐레이션 활동을 수행함에 있어서 고려해야 할 6가지의 현안들을 분석하고 논의하였다. 본 연구에서 제안되는 연구데이터 큐레이션 개념 모델은 총 10단계로 이루어져 있으며, 각 활동의 단계에서 고려해야 할 실천적 문제와 모순을 포함하고 있다.

• 한국산학기술학회논문지
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• 제13권11호
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• pp.5337-5344
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• 2012

본 연구는 지역사회에 거주하는 55세 이상의 건강한 집단과 뇌졸중 집단의 보유 활동 및 수준을 분석하고 후속 연구를 위한 집단 특이성을 알아보고자 하였다. 연구 자료 수집을 위하여 한국형 활동분류카드를 사용하였고, 기술통계 방법을 이용하여 건강한 집단과 뇌졸중 집단에서 활동보유수준을 확인하였으며, 스피어만 상관계수를 이용하여 일반적 정보와의 활동보유수준의 상관성을 분석하였고, 다중회귀분석을 사용하여 활동 보유 수준에 영향을 미치는 변인을 분석하였다. 건강한 집단의 구성원들이 수행하는 활동들이 뇌졸중 집단에서는 감소함를 확인할 수 있었으며, 상관관계 분석과 회귀분석 시 건강한 집단과 뇌졸중 집단에서 활동보유수준과 대상자의 일반적 정보간에 통계학적으로 유의미한 변인이 달랐다. 결과를 통하여 55세 이상의 건강한 집단과 뇌졸중 집단에서 활동보유수준과 집단별 특이성을 확인할 수 있었으며 결과 자료에 기초하여 해당 집단의 활동 참여 조정과 대치 시에 기초 자료로 사용할 수 있을 것이다.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2001년도 춘계학술대회 논문집
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• pp.74-80
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• 2001

The estimation of recurrence interval for fault activity and earthquake is an important input parameter for seismic hazard assessment. In this study, the methods of recurrences interval estimation were reviewed and tentative calculation was performed for age dating data which have uncertainty. Age dating data come from previous studies of Ulsan fault system which is a well developed lineament in the southeastern part of korean Peninsula. Age dating for fault gouges, parent rocks, Quaternary sediments and veins were carried out by several researchers through various methods. Recurrence interval for fault activity was estimated on the basis of the age dating data of minor fault gouge and sediments during past 3Ma. The estimated recurrence interval was about 430-500 ka. Exact estimation of recurrence interval for fault activity need to compile more geological data and fault characteristics such as fault length, amount of displacement, slip rate and accurate fault movement age. In the future, the methods and results of fault recurrence interval estimation should be considered for establishing the criteria for domestic active fault definition.