• Title/Summary/Keyword: Mean peak pressure

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A Study on Self-Esteem and Urinary Symptoms in Women with Urinary Incontinence (요실금환자의 골반근육운동에 따른 자아존중감과 배뇨증상에 관한 연구)

  • Lee Young-Hee;Kim Sun-Are
    • Journal of Korean Academy of Fundamentals of Nursing
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    • v.9 no.3
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    • pp.360-369
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    • 2002
  • Purpose: The purpose of this study was to help enhance the quality of life for women with urinary incontinence. Self-esteem, urinary symptoms, peak pressure and duration in seconds for vaginal contraction after pelvic muscles exercise were examined. Method: One-group pretest-posttest design was employed participants were 27 married women from G city. The instrument for this study were : the self-esteem scale developed by Rosenberg(1965). the Urinary Symptom Questionnaire, a subjective measurement of urinary incontinence, developed by Jackson et al.(1996) and the Perineometer used as an objective measurement of peak pressure and duration in seconds. Result: 1. Self-esteem showed significant improvement after the exercise (t=-3.832, p= .001). 2. Comparison of results before the pelvic muscles exercise and after showed that there was a statistically significant difference for several urinary symptoms including enuresis (t=2.833, p=.009), frequency of incontinence (t=2.964, p= .006), incontinence volume (t=2.280, p= .031), incontinence before getting to the restroom (t=3.035, p= .006), incontinence with no reason or feeling (t= 3.051, p= 005) burning sensation (t= 2.132, p=.043), and a sense of residual urine (t=2.267 p=.032). The mean scores showed improvement in the urinary symptoms of management of incontinence (M=$0.04{\pm}0.22$), daily frequency of incontinence management (M=$0.13{\pm}0.85$), urinary control (M=$0.15{\pm}0.86$), running to the restroom (M=$0.15{\pm}0.60$) incontinence caused by coughing or physical activities (M=$0.19{\pm}0.57$) and hesitancy (M=$0.07{\pm}0.55$). Overall urinary symptoms decreased significantly (t =3.073. p= .007). 3. Peak pressure showed an increase from a mean of $24.26{\pm}16.20mmHg$ before the exercise to a mean of $28.63{\pm} 17.79mmHg$ after (t=-2.399, p=.024). Duration in seconds also increased from a mean of $6.00{\pm}4.95sec$ to $9.15{\pm}5.83sec$ (t=-4.400, p= 000). Conclusion: These findings suggest that pelvic muscle exercise serves to decrease urinary problems, improve self-esteem and increase peak pressure and duration in seconds.

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Analysis of the Pressure Distribution for Press Shoe considering Partially Changed Curvature of Bearing Surface

  • Park, Sang-Shin;Park, Young-Ha;Lee, Young-Ze;Han, Man-Cheol
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2002.10b
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    • pp.123-124
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    • 2002
  • A press shoe is an element of a machine for squeezing water from wood pulp in the field of manufacturing paper. This is used to compress the pulp enveloped by felt sheet with a large roller. The squeezing force is made by hydraulic pressure. The press shoe has a mechanism similar to a partial hydrostatic bearing. The pressure profile between press shoe and roller affects their squeezing ability, and partial peak pressure can tear the wet pulp. The curvature of the surface of press shoe varies to reduce the peak pressure and increase the mean pressure simultaneously. Therefore, the prediction of pressure distribution considering partially changed curvature of hydrostatic bearing is very important for designing the press shoe. In this study, the difference formulation of Reynolds' equation for partial hydrostatic bearing is by direct numerical method and a computer program to calculate the pressure distribution is developed. We investigate the effect of partially changed curvature of bearing surface on the pressure distribution. Other design parameter for hydrostatic bearing such as depth of pocket and relative velocity are also studied.

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Analysis of the Pressure Distribution for Press Shoe considering Partially Changed Curvature of Bearing Surface

  • Park, Sang-Shin;Park, Young-Ha;Lee, Young-Ze;Han, Man-Cheol
    • KSTLE International Journal
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    • v.3 no.2
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    • pp.90-94
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    • 2002
  • A press shoe is an element of a machine for squeezing water from wood pulp in the field of manufacturing paper. This is used to compress the pulp enveloped by felt sheet with a large roller. The squeezing farce is made by hydraulic pressure. The press shoe has a mechanism similar to a partial hydrostatic bearing. The pressure profile between press shoe and roller affects their squeezing ability, and partial peak pressure can tear the wet pulp. The curvature of the surface of press shoe varies to reduce the peak pressure and increase the mean pressure simultaneously, Therefore, the prediction of pressure distribution considering partially changed curvature of hydrostatic bearing is very important far designing the press shoe. In this study, the difference formulation of Reynolds equation far partial hydrostatic bearing is derived by direct numerical method and a computer program to calculate the pressure distribution is developed. We investigate the effect of partially changed curvature of bearing surface on the pressure distribution. Other design parameter far hydrostatic bearing such as depth of pocket and relative velocity are also studied.

Effect of fuel injection timing and pressure on the combustion and spray behavior characteristics of diesel fuel for naval vessel (연료분사시기와 압력이 함정용 디젤연료의 분무 및 연소특성에 미치는 영향)

  • Lee, Hyung-min
    • Journal of Advanced Marine Engineering and Technology
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    • v.39 no.9
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    • pp.911-917
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    • 2015
  • The objective of this work focuses on the analysis of injection rate and macroscopic spray behavior characteristics with injection pressures as well as combustion and exhaust emission characteristics with injection timing and injection pressure by using a common rail single-cylinder diesel engine. The injection rate was measured by applying the Bosch method, and macroscopic spray behavior characteristics were analyzed with a constant-volume vessel and a high-speed camera. In addition, combustion and emission characteristics were analyzed in a common-rail single-cylinder diesel engine with precise control of fuel injection timing and pressure. For injection pressures of 30MPa and 50MPa, the injection rate was higher at 50 MPa, and the spray development (penetration) was also higher in the same elapsed time. The peak in-cylinder pressure and rate of heat release showed a tendency to decline as injection timing was delayed, and the peak in-cylinder pressure and rate of heat release were slightly higher for higher injection pressures. Higher injection pressures also reduced the mean effective pressure, while the indicated mean effective pressure and torque increased as injection timing was delayed to TDC. Nitrogen oxides had a peak level at injection timings of $BTDC20^{\circ}$(30MPa) and $BTDC15^{\circ}$(50MPa); carbon monoxide emissions were reduced by delaying injection timing from $BTDC30^{\circ}$.

Characteristics of Intraoral Air Pressure, Airflow in Relation to Phonatory Efficiency in Cleft Palate Speakers

  • Baek, Jin-A;Shin, Hyo-Keun
    • Proceedings of the KSLP Conference
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    • 2003.11a
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    • pp.147-147
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    • 2003
  • Recent aerodynamic and acoustic studies of VPI(velopharyngeal insufficiency) are non-invasive and safety, therefore, many researchers have used it to diagnose the hyper/hyponasality and articulation disorders of cleft palate patients. The purpose of this study was to estimate mainly the oropharyngeal air pressure and over all air flow in cleft lip and palate patients. The pressure-collecting catheter was positioned in the oropharyngel cavity around tongue base. Twelve adult control group and three cleft lip & palate patients were participated to this experimentation. Aerophone II was used to measure peak air flow, mean air flow, phonatory airflow, phonatory efficiency and resistance. The results were as follows: 1) Airflow of cleft lip & palate patients group were higher than those of control group. Fricative sounds /s/ and /s'/ showed the statistic significance of mean airflow and volume data. 2) Intraoral air pressure of cleft lip & palate patients was lower than those of control group.

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Effects of different wind deflectors on wind loads for extra-large cooling towers

  • Ke, S.T.;Zhu, P.;Ge, Y.J.
    • Wind and Structures
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    • v.28 no.5
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    • pp.299-313
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    • 2019
  • In order to examine the effects of different wind deflectors on the wind load distribution characteristics of extra-large cooling towers, a comparative study of the distribution characteristics of wind pressures on the surface of three large cooling towers with typical wind deflectors and one tower without wind deflector was conducted using wind tunnel tests. These characteristics include aerodynamic parameters such as mean wind pressures, fluctuating wind pressures, peak factors, correlation coefficients, extreme wind pressures, drag coefficients and vorticity distribution. Then distribution regularities of different wind deflectors on global and local wind pressure of extra-large cooling towers was extracted, and finally the fitting formula of extreme wind pressure of the cooling towers with different wind deflectors was provided. The results showed that the large eddy simulation (LES) method used in this article could be used to accurately simulate wind loads of such extra-large cooling towers. The three typical wind deflectors could effectively reduce the average wind pressure of the negative pressure extreme regions in the central part of the tower, and were also effective in reducing the root of the variance of the fluctuating wind pressure in the upper-middle part of the windward side of the tower, with the curved air deflector showing particularly. All the different wind deflectors effectively reduced the wind pressure extremes of the middle and lower regions of the windward side of the tower and of the negative pressure extremes region, with the best effect occurring in the curved wind deflector. After the wind deflectors were installed the drag coefficient values of each layer of the middle and lower parts of the tower were significantly higher than that without wind deflector, but the effect on the drag coefficients of layers above the throat was weak. The peak factors for the windward side, the side and leeward side of the extra-large cooling towers with different wind deflectors were set as 3.29, 3.41 and 3.50, respectively.

Determination of Minimal Pressure Support Level During Weaning from Pressure Support Ventilation (압력보조 환기법으로 기계호흡 이탈시 최소압력보조(Minimal Pressure Support) 수준의 결정)

  • Jung, Bock-Hyun;Koh, Youn-Suck;Lim, Chae-Man;Lee, Sang-Do;Kim, Woo-Sung;Kim, Dong-Soon;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.2
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    • pp.380-387
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    • 1998
  • Background: Minimal pressure support(PSmin) is a level of pressure support which offset the imposed work of breathing(WOBimp) developed by endotracheal tube and ventilator circuits in pressure support ventilation While the lower applied level of pressure support compared to PSmin could induce respiratory muscle fatigue, the higher level than PSmin could keep respiratory muscle rest resulting in prolongation of weaning period during weaning from mechanical ventilation PSmin has been usually applied in the level of 5~10 cm$H_2O$, but the accurate level of PSmin is difficult to be determinated in individual cases. PSmin is known to be calculated by using the equation of "PSmin = peak inspiratory flow rate during spontaneus ventilation$\times$total ventilatory system resistance", but correlation of calculated PSmin and measured PSmin has not been known. The objects of this study were firstly to assess whether customarily applied pressure support level of 5~10 cm$H_2O$ would be appropriate to offset the imposed work of breathing among the patients under weaning process, and secondly to estimate the correlation between the measured PSmin and calculated PSmin. Method : 1) Measurement of PSmin : Intratracheal pressure changes were measured through Hi-Lo jet tracheal tube (8mm in diameter, Mallinckroft, USA) by using pulmonary monitor(CP-100 pulmonary monitor, Bicore, USA), and then pressure support level of mechanical ventilator were increased until WOBimp was reached to 0.01 J/L or less. Measured PSmin was defined as the lowest pressure to make WOBimp 0.01 J/L or less. 2) Calculation of PSmin : Peak airway pressure(Ppeak), plateau airway pressure(Pplat) and mean inspiratory flow rate of the subjects were measured on volume control mode of mechanical ventilation after sedation. Spontaneous peak inspiratory flow rates were measured on CPAP mode(O cm$H_2O$). Thereafter PSmin was calculated by using the equation "PSmin = peak inspiratory flow rate$\times$R, R = (Ppeak-Pplat)/mean inspiratory flow rate during volume control mode on mechanical ventilation". Results: Sixteen patients who were considered as the candidate for weaning from mechanical ventilation were included in the study. Mean age was 64(${\pm}14$) years, and the mean of total ventilation times was 9(${\pm}4$) days. All patients except one were males. The measured PSmin of the subjects ranged 4.0~12.5cm$H_2O$ in 14 patients. The mean level of PSmin was 7.6(${\pm}2.5\;cmH_2O$) in measured PSmin, 8.6 (${\pm}3.25\;cmH_2O$) in calculated PSmin Correlation between the measured PSmin and the calculated PSmin is significantly high(n=9, r=0.88, p=0.002). The calculated PSmin show a tendancy to be higher than the corresponding measured PSmin in 8 out of 9 subjects(p=0.09). The ratio of measured PSmin/calculated PSmin was 0.81(${\pm}0.05$). Conclusion: Minimal pressure support levels were different in individual cases in the range from 4 to 12.5 cm$H_2O$. Because the equation-driven calculated PSmin showed a good correlation with measured PSmin, the application of equation-driven PSmin would be then appropriate compared with conventional application of 5~10 cm$H_2O$ in patients under difficult weaning process with pressure support ventilation.

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Pressure Fluctuations on Tapered and Setback Tall Buildings (비정형 초고층 건물의 변동 풍압)

  • Kim, Yong-Chul;Kanda, Jun;Tamura, Yukio;Yoon, Sung-Won
    • Journal of Korean Association for Spatial Structures
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    • v.13 no.1
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    • pp.97-104
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    • 2013
  • Recent tall buildings tend to have unconventional shapes as a prevailing, which is effective for suppressing across-wind responses. Suppression of across-wind responses is a major factor in tall building projects, and the so called aerodynamic modification method is comprehensively used. The purpose of the present study is to investigate the pressure fluctuations on tapered and setback tall buildings, including peak pressures, power spectra and coherences through the synchronous multi-pressure sensing system techniques. And flow measurements around the models were conducted to investigate the condition of vortex shedding. The results show that by tapering and setback, different distributions of mean pressure coefficients at leeward surface were found, which is caused by the geometric characteristics of the models. And the power spectra of wind pressures at sideward surface become wideband and the peak frequencies are different depending on heights, which makes the correlation near the Strouhal component low or even negative. The differences in shedding frequencies were also confirmed by the flow fields around the models.

An Aerodynamic and Acoustic Analysis of the Breathy Voice of Thyroidectomy Patients (갑상선 수술 후 성대마비 환자의 기식 음성에 대한 공기역학적 및 음향적 분석)

  • Kang, Young-Ae;Yoon, Kyu-Chul;Kim, Jae-Ock
    • Phonetics and Speech Sciences
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    • v.4 no.2
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    • pp.95-104
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    • 2012
  • Thyroidectomy patients may have vocal paralysis or paresis, resulting in a breathy voice. The aim of this study was to investigate the aerodynamic and acoustic characteristics of a breathy voice in thyroidectomy patients. Thirty-five subjects who have vocal paralysis after thyroidectomy participated in this study. According to perceptual judgements by three speech pathologists and one phonetic scholar, subjects were divided into two groups: breathy voice group (n = 21) and non-breathy voice group (n = 14). Aerodynamic analysis was conducted by three tasks (Voicing Efficiency, Maximum Sustained Phonation, Vital Capacity) and acoustic analysis was measured during Maximum Sustained Phonation task. The breathy voice group had significantly higher subglottal pressure and more pathological voice characteristics than the non breathy voice group. Showing 94.1% classification accuracy in result logistic regression of aerodynamic analysis, the predictor parameters for breathiness were maximum sound pressure level, sound pressure level range, phonation time of Maximum Sustained Phonation task and Pitch range, peak air pressure, and mean peak air pressure of Voicing Efficiency task. Classification accuracy of acoustic logistic regression was 88.6%, and five frequency perturbation parameters were shown as predictors. Vocal paralysis creates air turbulence at the glottis. It fluctuates frequency-related parameters and increases aspiration in high frequency areas. These changes determine perceptual breathiness.

The Peak Systolic Pressure-End Systolic Volume Index Relation in Patients with Coronary Artery Disease Using Radionuclide Gated Blood Pool Scintigraphy (관상동맥질환에서 심장풀스캔을 이용한 최고수축기혈압-수측기말용적곡선의 분석)

  • Kim, Byung-Tae;Koong, Sung-Soo;Bom, Hee-Seung;Chung, June-Key;Park, Young-Bae;Lee, Myung-Chul;Lee, Young-Woo;Koh, Chang-Soon
    • The Korean Journal of Nuclear Medicine
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    • v.21 no.2
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    • pp.175-182
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    • 1987
  • For measurement of ventricular performance, ejection fraction (EF) has gained wide acceptance. But EF is influenced not only by changes in muscle function but also by changes in cardiac loading conditions. In case of valvular heart disease which is variable in loading conditions, EF cannot be reliable as an index of myocardial contractility. The end systolic pressure (ESP)-end systolic volume (ESV) relation, howver, is known to represent myocardial contractility, independent of changes in loading conditions. Similar results can be obtained by using peak-systolic pressure (PSP) instead of ESP. To evaluate the utility of the peak systolic pressure-end systolic volume index (PSP-ESVI) relation as an index of myocardial function, we measured $PSP&ESVI$ in 19 partents with coronary artery disease before $(PSP_1\;&\;ESVI_1)$ and after $(PSP_2\;&\;ESVI_2)$ sublingual administration of nitroglycerin. PSP was measured with standard mercury sphygmomanometer during gated blood pool scintigraphic study. ESVI was measured by count derived method after attenuation correction. $PSP_2\;&\;ESVI_2$ measurement was started when the fall of PSP was greater than 5 mmHg after 7-14 minutes post-administration of nitroglycerin. Mean values $({\pm}S.D.)$ of $PSP_1\;&\;ESVI_1$ was $124.9({\pm}20.7)mmHg\;&\;59.4({\pm}39.9)ml/M^2$. Mean values $({\pm}S.D)$ of $PSP_2\;&\;ESVI_2$, was $113.2({\pm}19.9)mmHg\;&\;37.5({\pm}26.1)ml/M^2$. There was a significant difference between mean values of $PSP_1\;&\;PSP_2$, (p<0.01), and mean values of $ESVI_1\;&\;ESVI_2$, (p<0.01). $PSP_1-PSP_2/ESV_1-ESVI_2,\;PSP_1/ESVI_1$ and EF were in the range of 0.14-5.19 mmHg/ml/$M^2$, 0.67-7.68 mmHg/ml/$M^2$ and 10.8%-74.5% respectively. $PSP_1-PSP_2/ESVI_1-ESVI_2$, and EF showed exponential correlation (r=0.85, P<0.01). The correlation coefficient between $PSP_1/ESVI_1$ and EF was 0.73(p<0.01). With the above results, we suggest that $PSP_1-PSP_2/ESVI_1-ESVI_2$, and $PSP_1/ESVI_1$, can be used as an index of myocardial function.

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