• Journal of Acupuncture Research
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• v.31 no.3
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• pp.7-18
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• 2014

Objectives : The purpose of this study is to find parameters to compare the effects of Sa-Am acupuncture with large intestine tonifying and sedating on radial pulse in healthy subjects. Methods : Sixty healthy subjects participated in this study, divided into large intestine tonifying acupuncture group, large intestine sedating acupuncture group and control group. Radial pulse was measured by 3 dimensional pulse imaging system(DMP-3000) before, right after, 30 minutes after and 60 minutes after acupuncture at Cun, Guan, and Chi in the acupuncture group and in the control group at the same time points. Results : 1. Angle of main peak and magnitude of fourier component significantly changed by integrated analysis of Cun, Guan and Chi. 2. Amplitude of H1, Pulse Power volume / min, elasticity, AIx / HR, Frequency and magnitude of fourier component significantly changed by analysis of Cun, Guan, and Chi. Conclusions : The effect of Sa-Am acupuncture with large intestine tonifying and sedating in healthy human may be observed on time, amplitude, pulse area, augmentation index and fourier components parameters. The parameters analysed in this study may be used to differentiate the effects between Sa-Am acupuncture with large intestine tonifying and sedating on radial pulse. Further studies on the effects of Sa-Am acupuncture using radial pulse are needed.

• Journal of Acupuncture Research
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• v.30 no.4
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• pp.1-14
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• 2013

Objectives : The purpose of this study is to investigate the effects of Sa-Am spleen-tonifying acupuncture on radial pulse in healthy human subjects. Methods : Forty healthy human subjects participated in this study, divided into acupuncture group and control group. Radial pulse was measured by 3 dimensional pulse imaging system(DMP-3000) before, right after, 30 minutes after and 60 minutes after acupuncture in the acupuncture group. The subjects in the control group didn't received acupuncture but took a rest and then the radial pulse was measured at the same time points as the acupuncture group. The parameters were analyzed by gender, measuring location, and measuring time point. However the time related parameters exceptionally were analyzed without distinction of measuring location. Results : 1. T, variance of period, T2/T, T4/T, (T-T4)/T, T4/(T-T4), and W significantly changed after acupuncture. 2. Pressure, amplitude of H1, amplitude of H2, Amplitude of H4 and pulse energy significantly changed after acupuncture. 3. Pulse area, systolic pulse area and diastolic pulse area significantly changed after acupuncture. 4. Elasticity, AIx and AIx/HR significantly changed after acupuncture. Conclusions : The effect of Sa-Am spleen-tonifying acupuncture in healthy human may be observed on time, amplitude, pulse area and augmentation index. Further studies on the effects of Sa-Am acupuncture using radial pulse are needed.

• Steel and Composite Structures
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• v.20 no.2
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• pp.227-249
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• 2016

The objective of this work is to present a zeroth-order shear deformation theory for free vibration analysis of functionally graded (FG) nanoscale plates resting on elastic foundation. The model takes into consideration the influences of small scale and the parabolic variation of the transverse shear strains across the thickness of the nanoscale plate and thus, it avoids the employ use of shear correction factors. Also, in this present theory, the effect of transverse shear deformation is included in the axial displacements by using the shear forces instead of rotational displacements as in available high order plate theories. The material properties are supposed to be graded only in the thickness direction and the effective properties for the FG nanoscale plate are calculated by considering Mori-Tanaka homogenization scheme. The equations of motion are obtained using the nonlocal differential constitutive expressions of Eringen in conjunction with the zeroth-order shear deformation theory via Hamilton's principle. Numerical results for vibration of FG nanoscale plates resting on elastic foundations are presented and compared with the existing solutions. The influences of small scale, shear deformation, gradient index, Winkler modulus parameter and Pasternak shear modulus parameter on the vibration responses of the FG nanoscale plates are investigated.

• Journal of Families and Better Life
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• v.10 no.2
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• pp.19-36
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• 1992

The purpose of this paper is to analyze empirically the tendency of household consumption expenditure according to the change of social and economical condition, and the factor which influences consumption expenditure of urban household. The data used in analysis are time-series. The data are statistic form Urban Household Economy Survey published by the Economic Planning Board, dating form the first quarter of 1970 to the fourth quarter of 1989. The income of household and consumption expenditure materials were deflated as consumer price index to exclude the influence of prices and the influence of household composition are considered to deflated as the size of the household under assumption of homogeneity. The consumption expenditure items were categorized to 12 relatively large range items. The time-series data were analyzed by using the Two Stage Least Squares and the Ordinary Least Squares. The following is the result of analysis. 1) Rather than the income increase of previous years. the average income increase for two years influences more significantly on consumption expenditure of household. In the case of influence on consumption expenditure for each item by increase in disposable income, such categories as furniture and utensils. clothing and footwear, housing, medical care, culture and recreation, and transportation and communication have significant influence. 2) Among consumption expenditure categories, the increasing factors were furniture and utensils, and clothing and footwear. And the decreasing factors were housing, medical care, culture and recreation ,and transportation and communication. The relative prices, however, had significant influence on categories such as housing, furniture and utensils, medical care , culture and recreation, and transportation and communication and all of them were the decreation factors. 3) Among with changes of social and economical conditions, miscellaneous showed the highest increase in marginal propensity to consume and foods was the lowest. Also culture and recreation and housing brought up a great change of the income elasticity of demand.

• Smart Structures and Systems
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• v.20 no.6
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• pp.709-728
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• 2017

This disquisition proposes a nonlocal strain gradient beam theory for thermo-mechanical dynamic characteristics of embedded smart shear deformable curved piezoelectric nanobeams made of porous electro-elastic functionally graded materials by using an analytical method. Electro-elastic properties of embedded curved porous FG nanobeam are assumed to be temperature-dependent and vary through the thickness direction of beam according to the power-law which is modified to approximate material properties for even distributions of porosities. It is perceived that during manufacturing of functionally graded materials (FGMs) porosities and micro-voids can be occurred inside the material. Since variation of pores along the thickness direction influences the mechanical and physical properties, so in this study thermo-mechanical vibration analysis of curve FG piezoelectric nanobeam by considering the effect of these imperfections is performed. Nonlocal strain gradient elasticity theory is utilized to consider the size effects in which the stress for not only the nonlocal stress field but also the strain gradients stress field. The governing equations and related boundary condition of embedded smart curved porous FG nanobeam subjected to thermal and electric field are derived via the energy method based on Timoshenko beam theory. An analytical Navier solution procedure is utilized to achieve the natural frequencies of porous FG curved piezoelectric nanobeam resting on Winkler and Pasternak foundation. The results for simpler states are confirmed with known data in the literature. The effects of various parameters such as nonlocality parameter, electric voltage, coefficient of porosity, elastic foundation parameters, thermal effect, gradient index, strain gradient, elastic opening angle and slenderness ratio on the natural frequency of embedded curved FG porous piezoelectric nanobeam are successfully discussed. It is concluded that these parameters play important roles on the dynamic behavior of porous FG curved nanobeam. Presented numerical results can serve as benchmarks for future analyses of curve FG nanobeam with porosity phases.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.3
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• pp.102-113
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• 2017

A new index for the buckling strength of non-structured plates is proposed. The external work or the deformation energy caused by the external loads or the boundary displacement controled by a load parameter is calculated along an equilibrium path of the member under consideration. If the second variation of the energy with respect to the parameter loses its positiveness, it defined as the limit of the stability. In contrast to the current method given in codes where the stability limit is evaluated by using only representative internal forces, the evaluation of the stability limit is always consistent even with the change of the distribution of the internal forces on the boundary. If the elasticity is concerned, the result from this proposed approach becomes identical to that from the classical methods.

• Advances in nano research
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• v.7 no.4
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• pp.249-263
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• 2019

In the current paper, an exact solution method is carried out for analyzing the thermo-mechanical vibration of curved FG nano-beams subjected to uniform thermal environmental conditions, by considering porosity distribution via nonlocal strain gradient beam theory for the first time. Nonlocal strain gradient elasticity theory is adopted to consider the size effects in which the stress for not only the nonlocal stress field but also the strain gradients stress field is considered. It is perceived that during manufacturing of functionally graded materials (FGMs) porosities and micro-voids can be occurred inside the material. Material properties of curved porous FG nanobeam are assumed to be temperature-dependent and are supposed to vary through the thickness direction of beam which modeled via modified power-law rule. Since variation of pores along the thickness direction influences the mechanical and physical properties, porosity play a key role in the mechanical response of curved FG nano-structures. The governing equations and related boundary condition of curved porous FG nanobeam under temperature field are derived via the energy method based on Timoshenko beam theory. An analytical Navier solution procedure is utilized to achieve the natural frequencies of porous FG curved nanobeam supposed to thermal loading. The results for simpler states are confirmed with known data in the literature. The effects of various parameters such as nonlocality parameter, porosity volume fractions, thermal effect, gradient index, opening angle and aspect ratio on the natural frequency of curved FG porous nanobeam are successfully discussed. It is concluded that these parameters play key roles on the dynamic behavior of porous FG curved nanobeam. Presented numerical results can serve as benchmarks for future analyses of curve FG nanobeam with porosity phases.

• Steel and Composite Structures
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• v.49 no.4
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• pp.361-380
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• 2023

A size dependent bending behavior of piezoelectrical flexoelectric layered perforated functionally graded (FG) composite nanobeam rested on an elastic foundation is investigated analytically. The composite beam is composed of regularly cutout FG core and two piezoelectric face sheets. The material characteristics is graded through the core thickness by power law function. Regular squared cutout perforation pattern is considered and closed forms of the equivalent stiffness parameters are derived. The modified nonlocal strain gradient elasticity theory is employed to incorporate the microstructure as well as nonlocality effects into governing equations. The Winkler as well as the Pasternak elastic foundation models are employed to simulate the substrate medium. The Hamiltonian approach is adopted to derive the governing equilibrium equation including piezoelectric and flexoelectric effects. Analytical solution methodology is developed to derive closed forms for the size dependent electromechanical as well as mechanical bending profiles. The model is verified by comparing the obtained results with the available corresponding results in the literature. To demonstrate the applicability of the developed procedure, parametric studies are performed to explore influences of gradation index, elastic medium parameters, flexoelectric and piezoelectric parameters, geometrical and peroration parameters, and material parameters on the size dependent bending behavior of piezoelectrically layered PFG nanobeams. Results obtained revealed the significant effects both the flexoelectric and piezoelectric parameters on the bending behavior of the piezoelectric composite nanobeams. These parameters could be controlled to improve the size dependent electromechanical as well as mechanical behaviors. The obtained results and the developed procedure are helpful for design and manufacturing of MEMS and NEMS.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.4
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• pp.27-39
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• 2023

Purpose : The aim of this study was to identify the influence of transient isokinetic exercise on cardiac autonomic modulation and muscle properties in healthy male subjects. Methods : Twenty-eight healthy males underwent isokinetic exercise of both knee joints using a Biodex systems 3 isokinetic dynamometer with an angular velocity of 60 °/sec. The changes in activity of the autonomic nervous system, as determined by heart rate variability (HRV), and in muscle properties were evaluated at three times: pre-exercise, immediately post-exercise, and 10 min post-exercise. Results : The time domain analysis of HRV revealed significant changes in the beat count and mean and minimal heart rate (HR) measured at pre-exercise, immediately post-exercise, and 10 min post-exercise (p<.001). The beat count and mean HR were markedly increased immediately post-exercise compared to pre-exercise, but then significantly decreased at 10 min post-exercise (p<.001). All parameters of the frequency domain were significantly altered by isokinetic exercise (p<.01). The low frequency/high frequency (LF/HF) ratio, as an index for the sympathovagal balance, was elevated by exercise and remained at a similarly high level at 10 min post-exercise (p<.01). The muscle properties of rectus femoris were changed as follows: Muscle tone and stiffness were significantly increased between pre-exercise and immediately post-exercise (p<.001), and between pre-exercise and at 10 min post-exercise (p<.001). Whereas, the elasticity showed no significant change. Conclusion : These results demonstrated that transient isokinetic exercise could induce changes in cardiac autonomic control and muscle properties. In particular, up-regulation of LF/HF ratio after exercise signifies thus enhanced sympathetic modulation by isokinetic exercise. Therefore, it is needed to understand the cardiovascular risks that may arise during isokinetic exercise for providing the basic evidence to establish appropriate isokinetic exercise protocols as effective rehabilitation exercises.

• Korean Journal of Radiology
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• v.21 no.9
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• pp.1045-1054
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• 2020

Objective: This study aimed to evaluate the diagnostic value of combining the quantitative parameters of shear wave elastography (SWE) and superb microvascular imaging (SMI) to breast ultrasound (US) to differentiate between benign and malignant breast masses. Materials and Methods: A total of 200 pathologically confirmed breast lesions in 192 patients were retrospectively reviewed using breast US with B-mode imaging, SWE, and SMI. Breast masses were assessed based on the breast imaging reporting and data system (BI-RADS) and quantitative parameters using the maximum elasticity (Emax) and ratio (Eratio) in SWE and the vascular index in SMI (SMI_VI). The area under the receiver operating characteristic curve (AUC) value, sensitivity, specificity, accuracy, negative predictive value, and positive predictive value of B-mode alone versus the combination of B-mode US with SWE or SMI of both parameters in differentiating between benign and malignant breast masses was compared, respectively. Hypothetical performances of selective downgrading of BI-RADS category 4a (set 1) and both upgrading of category 3 and downgrading of category 4a (set 2) were calculated. Results: Emax with a cutoff value of 86.45 kPa had the highest AUC value compared to Eratio of 3.57 or SMI_VI of 3.35%. In set 1, the combination of B-mode with Emax or SMI_VI had a significantly higher AUC value (0.829 and 0.778, respectively) than B-mode alone (0.719) (p < 0.001 and p = 0.047, respectively). B-mode US with the addition of Emax, Eratio, and SMI_VI had the best diagnostic performance of AUC value (0.849). The accuracy and specificity increased significantly from 68.0% to 84.0% (p < 0.001) and from 46.1% to 79.1% (p < 0.001), respectively, and the sensitivity decreased from 97.6% to 90.6% without statistical loss (p = 0.199). Conclusion: Combining all quantitative values of SWE and SMI with B-mode US improved the diagnostic performance in differentiating between benign and malignant breast lesions.