• Journal of Advanced Marine Engineering and Technology
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• v.25 no.6
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• pp.1195-1202
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• 2001

The flow characteristics in a bifurcated duct are investigated experimentally. Physical properties such as mean velocity vectors, mean x-y stress distributions, mean vorticity and total pressure distributions are Obtained for three different Reynolds numbers(578, 620, 688) Using PIV measurements and CFD analysis. Also, three different rates of discharge Q=26.11 l/min, Q=28.11 $\ell$/min, Q=31.17 $\ell$/min) were selected foy experimental conditions. The results of this study would be useful to the engineer in designing the flow systems for heating, ventilation, air conditioning and wastewater purification plants.

• Physical Therapy Korea
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• v.13 no.4
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• pp.71-78
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• 2006

This study examined the effects of socket flexion angle in trans-tibial prosthesis on stump/socket interface pressure. Ten trans-tibial amputees voluntarily participated in this study. F-socket system was used to measure static and dynamic pressure in stump/socket interface. The pressure was measured at anterior area (proximal, middle, and distal) and posterior area (proximal, middle, and distal) in different socket flexion angles ($5^{\circ}$, $0^{\circ}$, and $10^{\circ}$). Paired t-test was used to compare pressure differences in conventional socket flexion angle of $5^{\circ}$ with pressures in socket flexion angles of $0^{\circ}$ and $10^{\circ}$ (${\alpha}$=.05). Mean pressure during standing in socket flexion angle of $10^{\circ}$ decreased significantly in anterior middle area (19.7%), posterior proximal area (10.4%), and posterior distal area (16.3%) compared with socket flexion angle of $5^{\circ}$. Mean pressure during stance phase in socket flexion angle of $0^{\circ}$ increased significantly in anterior proximal area (19.3%) and decreased significantly in anterior distal area (19.7%) compared with socket flexion angle of $5^{\circ}$. Mean pressure during stance phase in socket flexion angle of $10^{\circ}$ decreased significantly in anterior proximal area (19.6%) and increased significantly in anterior distal area (8.2%) compared with socket flexion angle of $5^{\circ}$. Peak pressure during gait in socket flexion angle of $0^{\circ}$ increased significantly in anterior proximal area (23.0%) compared with socket flexion angle of $5^{\circ}$ and peak pressure during gait in socket flexion angle of $10^{\circ}$ decreased significantly in anterior proximal area (22.7%) compared with socket flexion angle of $5^{\circ}$. Mean pressure over 80% of peak pressure ($MP_{80+}$) during gait in socket flexion angle of $0^{\circ}$ increased significantly in anterior proximal area (23.9%) and decreased significantly in anterior distal area (22.5%) compared with socket flexion angle of $5^{\circ}$. $MP_{80+}$ during gait in socket flexion angle of $10^{\circ}$ decreased significantly in anterior distal area (34.1%) compared with socket flexion angle of $5^{\circ}$. Asymmetrical pressure change patterns in socket flexion angle of $0^{\circ}$ and $10^{\circ}$ were revealed in anterior proximal and distal region compared with socket flexion angle of $5^{\circ}$. To provide comfortable and safe socket for trans-tibial amputee, socket flexion angle must be considered.

• Journal of Korean Academy of Nursing
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• v.39 no.2
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• pp.270-278
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• 2009

Purpose: This study was performed to find out the effects of lidocaine or 8.4% sodium bicarbonate mixed with rocuronium on mean arterial pressure, heart rate and withdrawal movement. Methods: Data collection was performed from December 15, 2006 through May 31, 2007. Seventy-five patients with American Society Anesthesiologist (ASA) physical status I & II, under general anesthesia, were randomly assigned to 1 of 3 groups: R group (RG) received rocuronium 0.6 mg/kg; RL group (RLG), rocuronium 0.6 mg/kg mixed with 2 mL of 2% lidocaine; RS group (RSG), rocuronium 0.6 mg/kg with the same volume of 8.4% sodium bicarbonate. Mean arterial pressure, heart rate and withdrawal movement were observed from its injection until 5 min after endotracheal intubation. Results: The incidence of withdrawal movement with its corresponding injections was 72%, 40% and 4% in RG, RLG and RSG, respectively (p<.001). Score of withdrawal movement was the lowest in RSG of all groups (p<.001). While mean arterial pressure (p=.011) in RSG decreased significantly, and heart rate (p=.003) in RG increased more with its injection than before induction of anesthesia. Conclusion: Administration of the equivalent volume of 8.4% sodium bicarbonate with rocuronium is more effective than that of lidocaine with rocuronium compared with rocuronium only, in preventing withdrawal movement and in stabilizing mean arterial pressure and heart rate.

• Wind and Structures
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• v.23 no.4
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• pp.367-383
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• 2016

The influence mechanism of mean value components, noted as $P_0$, on POD applications for complete random fields $P_C(t)$ and fluctuating random fields $P_F(t)$ are illustrated mathematically. The critical philosophy of the illustration is introduction of a new matrix, defined as the correlation function matrix of $P_0$, which connect the correlation function matrix of $P_C(t)$ and $P_F(t)$, and their POD results. Then, POD analyses for several different wind pressure fields were presented comparatively as validation. It's inevitable mathematically that the first eigenmode of $P_C(t)$ resembles the distribution of $P_0$ and the first eigenvalue of $P_C(t)$ is close to the energy of $P_0$, due to similarity of the correlation function matrixs of $P_C(t)$ and $P_0$. However, the viewpoint is not rigorous mathematically that the first mode represents the mean pressure and the following modes represent the fluctuating pressure when $P_C(t)$ are employed in POD application. When $P_C(t)$ are employed, POD results of all modes would be distorted by the mean value components, and it's impossible to identify $P_0$ and $P_F(t)$ separately. Consequently, characteristics of the fluctuating component, which is always the primary concern in wind pressure field analysis, can only be precisely identified with $P_0$ excluded in POD.

• Korean Journal of Community Nutrition
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• v.17 no.6
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• pp.737-751
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• 2012

The purpose of this study was to assess sodium and potassium intakes and urinary excretion of adults in Busan and to evaluate the relationship of urinary sodium/potassium excretion (UNa/UK) to the status of anthropometric, blood pressure, urine analysis, and nutrient intake of subjects. Nutrient intake by 24-h recall, 24-h UNa/UK were measured with 87 adults aged 20-59 yrs (42 men and 45 women). The mean intakes of sodium and potassium were 3915.4 mg and 3093.9 mg, respectively. The mean 24-h UNa/UK was 3457.0/1680.4 mg. UNa showed significant positive correlations with sodium intake (p < 0.001, p < 0.001), sodium/potassium ratio (p < 0.001, p < 0.01), UK (p < 0.001, p < 0.001), and UNa/UK ratio (p < 0.05, p < 0.01) in men and women and with age, BMI, systolic blood pressure (SBP) and diastolic blood pressure in women (p < 0.05, p < 0.05, p < 0.05, p < 0.05). The UK showed significant positive correlations sodium intake (p < 0.001, p < 0.001), UNa (p < 0.001, p < 0.001) in men and women and with sodium density in men (p < 0.001) and with age, intakes of protein and potassium in women (p < 0.01, p < 0.05, p < 0.05). Mean SBP was lowest in the second quartile and highest in the fourth quartile of UNa. Mean UNa in the second, third, and fourth quartiles were 2821.1 mg, 3621.3 mg, and 5456.4 mg, respectively. Mean SBP in the second, third, and fourth quartiles were 115.8 mmHg, 120.7 mmHg, and 125.9 mmHg, respectively. Based on the results, UNa was related to sodium intake, UK, and SBP. We conclude that nutritional education for the reduction of high sodium intake is needed in the general population to prevent and control adverse blood pressure levels.

• Journal of Korean Academy of Nursing
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• v.19 no.3
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• pp.285-298
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• 1989

This study investigated the effect of changing position from supine to standing upright on the circulation of young men and women. Healthy men and women ranging from age of 18 to 24 were examined. Two minutes before standing, the baseline heart rate and blood pressure were measured. Heart rate and blood pressure were recorded immediately and at every minute for 10 minutes after standing upright. Differences in heart rate and blood pressure between supine and standing upright position were evaluated. The results were summarized as follows : 1. Heart rate increased significantly immediately and at every minute for 10 minutes after standing upright. 2. Systolic blood pressure increased significantly immediately and at every minute for 4 minutes after standing upright. 3. Diastolic and mean blood pressure increased significantly immediately and at every minute for 10 minutes after standing upright. 4. Pulse pressure immediately and at every minute for 10 minutes after standing upright was significantly narrower than that of supine position. 5. There was no significant difference of heart rate between men and women after standing upright. 6. Systolic and diastolic blood pressure of men after standing upright was significantly greater than those of women. From these results, it may be concluded that heart rate, systolic, diastolic and mean blood pressure and pulse pressure increase after standing upright, and systolic and diastolic blood pressure in men is greater than those of women after standing upright.

• The Korean Journal of Pain
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• v.14 no.1
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• pp.32-36
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• 2001

Background: There is no reliable objective test for the diagnosis of myofascial pain syndromes. The aim of this study was to evaluate the usefulness of a pressure algometer for the diagnosis of the trigger points and for the evaluation of the treatment in myofascial pain syndromes (MPS). Methods: Twenty female patients with clinical MPS of shoulder were included in this study. Pressure pain thresholds were measured by a pressure algometer at three different sites including the trapezius, supraspinatus and infraspinatus before, and then the 1st, 3rd and 7th days after TPI. Results: Mean pressure pain thresholds were lower in patients with MPS in than normal volunteers in all the examined skeletal muscles. Mean pressure pain thresholds in patients with MPS were increased significantly after TPI in all the examined skeletal muscles. Conclusions: Pressure algometer can be used as relatively objective diagnostic tool for locating trigger points and to quantify the effect of TPI in MPS. However, more investigation is necessary.

• Transactions on Electrical and Electronic Materials
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• v.9 no.1
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• pp.38-43
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• 2008

Using an arterial pressure-volume (APV) model, we performed an analysis of the conventional blood pressure estimation method using an oscillometric sphygmomanometer with computer simulation. Traditionally, the maximum amplitude algorithm (MAA) has been applied to the oscillation waveforms of the APV model to obtain the mean arterial pressure and the characteristic ratio. The estimation of mean arterial pressure and characteristic ratio was significantly affected by the shape of the blood pressure waveforms and the cutoff frequency of high-pass filter (HPF) circuitry. Experimental errors result from these effects when estimating blood pressure. To determine an algorithm independent of the influence of waveform shapes and parameters of HPF, the volume oscillation of the APV model and the phase shift of the oscillation with fast Fourier transform (FFT) were tested while increasing the cuff pressure from 1 mmHg to 200 mmHg (1 mmHg/s). The phase shift between ranges of volume oscillation was then only observed between the systolic and the diastolic blood pressures. The same results were obtained from simulations performed on two different arterial blood pressure waveforms and one hyperthermia waveform.

• Wind and Structures
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• v.24 no.2
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• pp.145-169
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• 2017

The auxiliary structures of a high-rise building, such as balconies, ribs, and grids, are usually much smaller than the whole building; therefore, it is difficult to simulate them on a scaled model during wind tunnel tests, and they are often ignored. However, they may have notable effects on the local or overall wind loads of the building. In the present study, a series of wind pressure wind tunnel tests and high-frequency force balance (HFFB) wind tunnel tests were conducted on rigid models of an actual super high-rise building with vertical ribs protruding from its facades. The effects of the depth and spacing of vertical ribs on the mean values, fluctuating values and the most unfavorable values of the local wind pressure coefficients were investigated by analyzing the distribution of wind pressure coefficients on the facades and the variations of the wind pressure coefficients at the cross section at 2/3 of the building height versus wind direction angle. In addition, the effects of the depth and spacing of vertical ribs on the mean values, fluctuating values and power spectra of the overall aerodynamic force coefficients were studied by analyzing the aerodynamic base moment coefficients. The results show that vertical ribs significantly decrease the most unfavorable suction coefficients in the corner recession regions and edge regions of facades and increase the mean and fluctuating along-wind overall aerodynamic forces.

• Journal of the Korean Society of Industry Convergence
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• v.2 no.2
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• pp.115-124
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• 1999

The interaction of weak normal shock wave with turbulent boundary layer in a supersonic nozzle was investigated experimentally by wall static pressure measurements and by schlieren optical observations. The lime-mean flow in the interaction region was classified into four patterns according to the ratio of the pressure $p_k$ at the first kink point in the pressure distribution of the interaction region to the pressure $p_1$ just upstream of the shock. It is shown for any flow pattern that the wall static pressure rise near the shock foot can be described by the "free interaction" which is defined by Chapman et al. The ratio of the triple point height $h_t$ of the bifurcated shock to the undisturbed boundary layer thickness ${\delta}_1$ upstream of the interaction increases with the upstream Mach number $M_1$, and for a fixed $M_1$, the normalized triple point height $h_t/{\delta}_1$ decreases with increasing ${\delta}_1/h$, where h is the duct half-height.