• Title/Summary/Keyword: Long-range Correlation

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Relationships of Activities of Daily Living and Body Image with Quality of Life in Stroke Patients: Mediating Effects of Interpersonal Relations (뇌졸중 환자의 일상생활 수행능력, 신체상이 삶의 질에 미치는 영향: 대인관계 매개효과 중심)

  • Kim, Minju;Park, Hyomin
    • Journal of muscle and joint health
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    • v.28 no.2
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    • pp.183-191
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    • 2021
  • Purpose: This study was conducted to identify factors associated with stroke patients' quality of life (QOL) and examine the mediating effects of interpersonal relations in the relationships of activities of daily living (ADL) and body image with QOL. Methods: In this study, 160 stroke patients were recruited from an outpatient clinic of a university hospital and rehabilitation clinic of a long-term care hospital. Participants completed a questionnaire which included sociodemographic characteristics, ADL, body image, interpersonal relation, and QOL. Descriptive statistics, t-tests, ANOVA, Pearson's correlation coefficients, multiple regression analysis, and process macro mediation analysis were conducted using SPSS. Results: The mean scores were 91.01 (range 6~100) for ADL, 61.19 (range 40~79) for body image, 87.53 (range 29~123) for interpersonal relations, and 186.67 (range 71~243) for QOL. Multiple regression analyses showed that ADL, body image, interpersonal relations, and participation in group activities after stroke were significantly associated with QOL among stroke patients (p<.05). There were no mediating effects of interpersonal relations in the relationships of ADL and body image with QOL (p>.05). Conclusion: This study showed that there is a need for physical, psychological, and social recovery to improve the QOL of stroke patients.

Comparison of physical fitness according to body mass index of Chinese college students (중국 대학생의 체질량지수에 따른 체력 비교)

  • Chen, Fu;Kim, Jung-Hyun;Kim, Ok-ja
    • Journal of Korean Physical Therapy Science
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    • v.28 no.3
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    • pp.53-65
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    • 2021
  • Background: The purpose of this study was to a comparison of physical fitness according to the body mass index (BMI) of Chinese college students. Design: Cross-sectional study. Methods: According to the BMI, the research objects are divided into four types: underweight, normal weight, overweight, and obesity. This research took 26,976 college students who participated in Jiujiang College. It examines BMI, 50m, vital capacity, standing long jump, sitting forward bend, sit-up (female), pull-up (male), 800m (female), 1000m (male) which is to research the correlation between different BMI and other indicators. Results: The physical qualities of students with normal weight are significantly better than those with other BMI groups. Pearson correlation analysis showed that male BMI was positively correlated with vital capacity (r=0.07, p<0.01), 50m (r=0.15, p<0.01) and 1000m (r=0.14, p<0.01), and negatively correlated with standing long jump (r=-0.12, p<0.01), sitting forward bend (r=-0.06, p<0.01) and pull-up (r=-0.13, p<0.01); Female BMI was positively correlated with vital capacity (r=0.03, p<0.01), 50m (r=0.21, p<0.01) and 800m (r=0.18, p<0.01), and negatively correlated with standing long jump (r=-0.07, p<0.01), sitting forward bend (r=-0.11, p<0.01) and sit-up (r=-0.10, p<0.01). Conclusion: Overweight and underweight will affect the physical quality of college students. Students should keep their BMI within the normal range for their health.

A Study on Optimal Hydrophone Arrangement for The Direction Finding of High Speed Moving Target in Underwater (수중에서 고속 기동하는 표적의 방위 탐지를 위한 최적의 청음기 배치 연구)

  • Han, Min-Su;Choi, Jae-Yong;Kang, Dong-Seok;Son, Kweon;Lee, Phil-ho
    • Journal of the Korea Institute of Military Science and Technology
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    • v.20 no.3
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    • pp.369-375
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    • 2017
  • One of good DF(Direction Finding) methods is based on TDOA(Time Difference of Arrival) estimation when finding underwater moving target. For small DF error, high time resolution A/D(Analog-to-digital) conversion board and long baseline are needed. But the result of sea trial about close-range and high speed moving target, spatial correlation coefficient and appeared poor properties below 0.3 when hydrophone arrangement are separated over 6 ${\lambda}$ because of underwater fading channel. And we also find out that the distance between hydrophone should be under 4 ${\lambda}$ apart to take advantage of spatial correlation coefficient gain and performance of DF in underwater moving channel environments.

Elimination of environmental temperature effect from the variation of stay cable force based on simple temperature measurements

  • Chen, Chien-Chou;Wu, Wen-Hwa;Liu, Chun-Yan;Lai, Gwolong
    • Smart Structures and Systems
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    • v.19 no.2
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    • pp.137-149
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    • 2017
  • Under the interference of the temperature effect, the alternation of cable force due to damages of a cable-stayed bridge could be difficult to distinguish. Considering the convenience and applicability in engineering practice, simple air or cable temperature measurements are adopted in the current study for the exclusion of temperature effect from the variation of cable force. Using the data collected from Ai-Lan Bridge located in central Taiwan, this work applies the ensemble empirical mode decomposition to process the time histories of cable force, air temperature, and cable temperature. It is evidently observed that the cable force and both types of temperature can all be categorized as the daily variation, long-term variation, and high-frequency noise in the order of decreasing weight. Moreover, the correlation analysis conducted for the decomposed variations of all these three quantities undoubtedly indicates that the daily and long-term variations with different time shifts have to be distinguished for accurately evaluating the temperature effect on the variation of cable force. Finally, consistent results in reducing the range of cable force variation after the elimination of temperature effect confirm the validity and stability of the developed method.

Application of SDAHL-74 Watershed Model to a Long Term Runoff Analysis in the Mountainous Watershed (산지유역에 대한 USDAHL-74 유역수문모형의 장기유출 해석적용)

  • 권순국;고덕구
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.29 no.2
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    • pp.53-63
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    • 1987
  • Due to their wide range of application, deterministic comprehensive hydrologic models using digital computers have been developed in all countries of the world and researches are being undertaken for their appropriate applications. The aim of this study has been to demonstrate the practical implementation of a physically based distributed hydrologic model, the USDAHL-74 model and to investigate its ability to simulate the long term estimate of water balance quantities in a Korean mountainous watershed. Application of the model to Dochuk watershed indicates the following results. 1.Since the USDAHL-74 model includes all the major components of the hydrologic cycle in agricultural watersheds, thus is comprehnsive, the model seems to have a wide range of application from the fact that simulation results obtained are not only runoff volumes m various time units but their spatial variation as well as even soil moisture within the watershed. 2.An approximate calibration to determine the parameter values in the model using various data obtained from D0chuk shed shows that the simulation error of yearly runoff volume is only 0.6 % and a correlation coefficient between observed daily runoff volume and simulated one is 0.91 in all calibrated period.3.As a verification test of the model, runoff volumes are simulated using 1986 year data without changing the parameter values determined by 1985 year data. The tests show that the USDAHL-74 model is a flexible tool and that realistic production to simulate the long term estimate of runoff in Korean mountainous watershed could be obtained using only a short period of calibration.4. Despite of the encouraging results, there still remain minor problems concerning the practical application of the model to improve the result of simulations. Some of these are the small descrepancies between observed and simulated daily runoff volume appeared in the vicinity of peaks and the recession of1 the daily hydrographs and the model performance for the frozen ground and melting process in the model. 5. Alough the use of parameter with physical significance and the ability to improve calibrations on the basis of physical reasoning represents advantages in the simulation for ungaged watersheds, further researches are needed to use the USDAHL-74 mode to simulate runoff in ungaged watersheds.

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A Study on Continuous long-term Wave Observation using Remote Monitoring System (원격모니터링을 이용한 연속파랑관측에 관한 연구)

  • Shin, Bumshick
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.1
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    • pp.654-659
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    • 2018
  • In this study, continuous long-term observation is implemented with an ocean radar. Ocean radar conducts remote observation (combined) with ground-based radars, which enable a series of simultaneous observations of an extensive range of the coast with high frequency. An ocean radar for continuous long-term observation is operated at Samcheok on the east coast of Korea. Samcheok experienced tsunami damage in recent years and is the location of a nuclear power plant. In order to examine the reliability of the ocean radar, a pressure-type wave gauge, ultrasonic wave gauge, and ocean buoy are installed for the purpose of data comparison and verification. The ocean radar used in this study is an array-type HF-RADAR named WERA (WavE RAdar). The analysis of the data obtained from continuous long-term observations showed that the radar observations were in agreement with more than 90% of the wave data collected within a 25 km range from the center of two sites. Less than 1% of the entire observation data was unmeasured by the time series analysis. As a result of comparing the radar data with the direct observations made by the wave gauge, it was inferred that the RMS deviation is less than 20cm and the correlation coefficient was in the range of 0.84 ~ 0.87. Moreover, supported by such observations, a comprehensive monitoring system is being developed to provide the public with real-time reports on waves and currents via the internet.

Evaluation on Expectation of Deflection of Floor Damping Materials Subjected to Long-Term Load (장기하중을 받는 바닥완충재의 처짐 예측 평가)

  • Kim, Jung-Min;Hong, Yoon-Ki;Kim, Jin-Koo;Lee, Jung-Yoon
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.20 no.4
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    • pp.19-26
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    • 2016
  • Floor damping materials used in floating floor system to diminish the floor noise have been made with low density and dynamic stiffness. Owing to this low density and dynamic stiffness, the deflection in these materials under long-term loading and cracking of the floor finishing mortar in the floating floor system may occur. This paper presents the results of long-term loading effects on the deflection of different types of floor damping materials. The experimental program involved the long-term loading tests for 490 days loading period on sixteen specimens. Specimens were classified as DM1(Damping Materials) to DM8, depending upon the four main parameters; types, bottom shapes and densities of floor damping materials and amount of loading. Results indicated that the long-term deflection of all specimens of damping materials remained unchanged after 200 days at all loading amounts, except the specimens made up of Polystrene, in which long-term deflection remained unchanged after 160 days at 250 N load and 100 days 500 N load. In this paper, two types of correlation expressions were shown in the deflection range prior to the range where deflection remained constant; two analyses by ISO 20392 and linear regression. In comparison of two analyses and experimental results on the difference of deflection of 16 specimens, the difference of deflection was below 0.4 mm in those analyses in case of that total deflection was below 10 mm. Restrictively, it was judged that the analysis for the deflection of specimens made up of Polystrene is more appropriate using ISO 20392.

Comparing Physical and Thermal Environments Using UAV Imagery and ENVI-met (UAV 영상과 ENVI-met 활용 물리적 환경과 열적 환경 비교)

  • Seounghyeon KIM;Kyunghun PARK;Bonggeun SONG
    • Journal of the Korean Association of Geographic Information Studies
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    • v.26 no.4
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    • pp.145-160
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    • 2023
  • The purpose of this study was to compare and analyze diurnal thermal environments using Unmanned Aerial Vehicles(UAV)-derived physical parameters(NDVI, SVF) and ENVI-met modeling. The research findings revealed significant correlations, with a significance level of 1%, between UAV-derived NDVI, SVF, and thermal environment elements such as S↑, S↓, L↓, L↑, Land Surface Temperature(LST), and Tmrt. In particular, NDVI showed a strong negative correlation with S↑, reaching a minimum of -0.52** at 12:00, and exhibited a positive correlation of 0.53** or higher with L↓ at all times. A significant negative correlation of -0.61** with LST was observed at 13:00, suggesting the high relevance of NDVI to long-wavelength radiation. Regarding SVF, the results showed a strong relationship with long-wave radiative flux, depending on the SVF range. These research findings offer an integrated approach to evaluating thermal comfort and microclimates in urban areas. Furthermore, they can be applied to understand the impact of urban design and landscape characteristics on pedestrian thermal comfort.

A Study on the Linear Array Beamforming by Cross Correlation Matrix (상호상관 행렬을 이용한 선배열 빔형성 기법 연구)

  • 황수복;이성은
    • The Journal of the Acoustical Society of Korea
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    • v.20 no.7
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    • pp.31-36
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    • 2001
  • Passive sonar system forms the various beams in any desired directions to obtain the improvement in Signal-to-Noise (S/N) ratio, bearing detection and localization of targets, and the attenuation of interferences from other directions. The improvement of beamforming is very important to detect modern underwater targets as noise reduction technology leads to considerably low-level acoustic emissions in the long range in complex environmental sea. In this paper, we proposed the spatial cross correlation beamforming (SCCBF) algorithm using cross correlation matrix of individual hydrophone pairs of linear array sensors. By the theoretical analysis and simulation, the proposed SCCBF is demonstrated that its performances compared to conventional beamforming (CBF) output can be obtain above 3dB of array gain and about half of beam width represented the bearing accuracy in target detection. Also, this paper presents sea test result of linear passive sonar system that the proposed algorithm implemented.

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An Analysis of Long-Term Variation of PM10 Levels and Local Meteorology in Relation to Their Concentration Changes in Jeju (제주지역 미세먼지의 장기변동 및 농도변화에 관한 국지기상 분석)

  • Park, Yeon-Hee;Song, Sang-Keun;Lee, Soo-Jeong;Kim, Suk-Woo;Han, Seung-Bum
    • Journal of Environmental Science International
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    • v.25 no.1
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    • pp.107-125
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    • 2016
  • Long-term variations of $PM_{10}$ and the characteristics of local meteorology related to its concentration changes were analyzed at 4 air quality sites (Ido-dong, Yeon-dong, Donghong-dong, and Gosan) in Jeju during two different periods, such as PI (2001-2006) and PII (2007-2013), over a 13-year period. Overall, the long-term trend of $PM_{10}$ was very slightly downward during the whole study period, while the high $PM_{10}$ concentrations in PII were observed more frequently than those in PI. The concentration variations of $PM_{10}$ during the study period was clarified in correlation between $PM_{10}$ and meteorological variables, e.g. the low (high) $PM_{10}$ concentration with large (small) precipitation or high (low) radiation and in part high $PM_{10}$ concentrations (especially, Donghong-dong and Gosan) with strong wind speed and the westerly/northwesterly winds. This was likely to be caused by the transport effect (from the polluted regions of China) rather than the contribution of local emission sources. The $PM_{10}$ concentrations in "Asian dust" and "Haze" weather types were higher, whereas those in "Precipitation", "Fog", and "Thunder and Lighting" weather types were lower. The contribution of long-range transport to the observed $PM_{10}$ levels in the urban center (Ido-dong, Yeon-dong, and Donghong-dong), if estimated by comparison to the data of the background site (Gosan), was found to explain about 80% (on average) of its input.