• Title/Summary/Keyword: Power Spectral Density Function

Search Result 132, Processing Time 0.021 seconds

Characteristic Radial Pulse Properties of Elderly Females according to Sasang Constitution-based Health Level (고령자 여성의 체질건강수준에 따른 맥파 특성 연구)

  • Kim, Jae Uk;Bae, Jang Han;Ku, Bon Cho;Jeon, Young Ju;Kim, Keun Ho;Kim, Jong Yeol;Kim, Young Min
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.26 no.6
    • /
    • pp.970-975
    • /
    • 2012
  • In Sasang constitutional medicine, doctors diagnose and treat patients according to their Sasang consitutition (SC) type. In this work, by a clinical test with a radial pulse tonometer, we investigated radial pulse properties which were significant in distinguishing unhealthy subjects from healthy subjects for each SC type. We measured radial pulse properties on left and right Gwan locations with a pulse tonometer for 299 elderly female subjects of age of 50 years old or above. We used a newly developed SCAT system to determine subjects' SC types. Subjects' health levels of either healthy or unhealthy were determined independently by two Korean medical doctors. To investigate the statistical differences, we used either of Student's t-test or Mann-Whitney U test depending on the normality of distribution of test statistic. For TE type, unhealthy subjects were characterized with significant increases in heart rate, systolic to diastolic period, pulse depth, while they showed significant decreases in width of pulse in normal direction, pulse area in diastolic period, and high harmonic components (6th, 7th) of power spectral density. For SE type, unhealthy subjects were characterized with significant increases in pulse pressure and pulse depth, while no significant differences were found for SY type. We investigated the characteristic differences in radial pulse properties due to change in health levels on each SC type for elderly females. Pulse variables which were significantly different between healthy subjects and unhealthy subjects were found to vary between SC types. For TE type subjects, many variables were found significant at the left Gwan location, which is in support of the theory of hyperactive liver functioning for TE type. Irrespective of the constitution, the related changes in the pulse properties due to worsened health level were in support of elevated blood flow amount in compensation with weakened blood circulatory function.

Dynamic Load Allowance of Highway Bridges by Numerical Dynamic Analysis for LRFD Calibration (LRFD 보정을 위한 동적해석에 의한 도로교의 동적하중허용계수)

  • Chung, Tae Ju;Shin, Dong-Ku;Park, Young-Suk
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.28 no.3A
    • /
    • pp.305-313
    • /
    • 2008
  • A reliability based calibration of dynamic load allowance (DLA) of highway bridge is performed by numerical dynamic analysis of various types of bridges taking into account of the road surface roughness and bridge-vehicle interaction. A total of 10 simply supported bridges with three girder types in the form of prestressed concrete girder, steel plate girder, and steel box girder is analyzed. The cross sections recommended in "The Standardized Design of Highway Bridge Superstructure" by the Korean Ministry of Construction are used for the prestressed concrete girder bridges and steel plate girder bridges while the box girder bridges are designed by the LRFD method. Ten sets of road surface roughness for each bridge are generated from power spectral density (PSD) function by assuming the roadway as "Average Road". A three dimensionally modeled 5-axle tractor-trailer with its gross weight the same as that of DB-24 design truck is used in the dynamic analysis. For the finite element modeling of superstructure, beam elements for the main girder, shell elements for concrete deck, and rigid links between main girder and concrete deck are used. The statistical mean and coefficient of variation of DLA are obtained from a total of 100 DLA results for 10 different bridges with each having 10 sets of road surface roughness. Applying the DLA statistics obtained, the DLA is finally calibrated in a reliability based LRFD format by using the formula developed in the calibration of OHBDC code.