• Title/Summary/Keyword: volume function

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Effect of Hemodialysis on Left and Right Ventricular Volume and Function (말기신질환에서 혈액투석에 따르는 좌우심실용적 및 기능변화에 관한 연구)

  • Han, Jin-Suk;Koh, Chang-Soon
    • The Korean Journal of Nuclear Medicine
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    • v.19 no.2
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    • pp.43-50
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    • 1985
  • With the improvement of hemodialysis, the course of the disease in patient with endstage renal disease has been clearly improved. Nevertheless, among several shortcomings to our present mode of renal replacement therapy, cardiovascular complications have been the leading cause of morbidity and mortality. Several factors such as anemia, arteriovenous shunting of blood, intermittent extracorporeal circulation and hypertension may be contributing. But little is known about the quantitative cardiac hemodynamic characteristics occurred during hemodialysis. The purpose of this study is to observe the sequential hemodynamic changes before, during and after the hemodialysis and to investigate reliable parameters in the detection of ventricular dysfunction. In the present study, equilibrium radionuclide cardiac angiography was performed and left and right ventricular volume indices, ejection phase indices of both ventricular, performance were measured in the 16 stable patients with chronic renal failure treated with maintenance hemodialysis sequentially i.e. before, during (early and late phase) and after the hemodialysis. The results obtained were as follows; 1) The indices of the left ventricular function were not changed during the hemodialysis but increased after the hemodialysis. 2) The indices of the right ventricular function(EF, SVI) were significantly decreased in the early phase (15, 30 minutes after starting extracorporeal circulation) but recovered after the hemodialysis. 3) The ratio of right ventricular to left ventricular ejection fraction was significantly decreased in the early phase and the lung volume indices were significantly increased at the same phase. As a conclusion, hemodialysis improves left ventricular function maybe due to increased contractility, and effects on the right ventricular function maybe due to the increased lung volume in the early phase of hemodialysis.

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The Effects of Abdominal Muscle Strengthening Exercise on Abdominal Muscle Strength and Respiratory Function in Stroke Patients (배근 강화운동이 뇌졸중 환자의 배근력 및 호흡기능에 미치는 영향)

  • Kang, Taewook;Jung, Juhyeon
    • Journal of The Korean Society of Integrative Medicine
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    • v.7 no.4
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    • pp.13-21
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    • 2019
  • Purpose : The purpose of this study was to investigate the effect of abdominal muscle strengthening exercise on abdominal muscle strength and respiratory function in stroke patients. Methods : The subjects were 14 stroke patients (10 males, 4 females) hospitalized at W rehabilitation hospital in Busan City and randomly assigned to 7 exercise groups and 7 control groups. Exercise was performed in combination with an upper and lower extremity pattern of proprioceptive neuromuscular facilitation. Measurements of abdominal muscle strength and respiratory function were made before intervention and 4 weeks after intervention. Abdominal muscle strength was assessed using a digital manual dynamometer, and respiratory function was assessed by spirometry. The collected data were analyzed with a paired t-test and independent t-test and the significance level was set as α =.05. Results : The results showed that applying abdominal muscle strengthening exercise to stroke patients showed a significant increase in abdominal muscle strength and a significant difference between groups (p<.05). Maximal-effort expiratory spirogram (MES) readings were significantly increased in forced vital capacity (FVC), and forced expiratory volume in one second (FEV1), in the exercise group, and there were a significant differences between the groups in terms of FEV1 (p<.05). Slow vital capacity (SVC) was significantly increased in vital capacity (VC), tidal volume (TV), inspiratory reserve volume (IRV), and expiratory capacity (EC), and there were significant differences between the groups in VC, TV, expiratory reserve volume (ERV), EC, and inspiratory capacity (IC) (p<.05). Conclusion : Abdominal muscle strengthening exercise was effective in the abdominal muscle strength of stroke patients, and it was confirmed to have a positive effect on the enhancement of respiratory function. Therefore, it seems that exercise programs for stroke patients with respiratory weakness should include abdominal muscle strengthening exercises.

Comparison of Posture on Respiratory Function in the Stroke Patients according to Changes of Position (뇌졸중 환자의 자세변화에 따른 폐기능비교)

  • Seo, Kyo-Chul;Lee, Sung-Eun;Lee, Jeon-Hyeong;Kim, Kyoung
    • Journal of the Korean Society of Physical Medicine
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    • v.6 no.4
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    • pp.381-389
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    • 2011
  • Purpose : The purpose of this study was to compare the respiratory function in the different body position of the stroke patients. Methods : Twenty patients with stroke patients group(M:12, F:8) and twenty control group(M:12, F:8) were participated in experiment. Strokes patients group and control group were assessed according to position changes(supine position, $45^{\circ}$ sitting position, $90^{\circ}$ sitting position) using pulmonary function(vital capacity, inspiratory capacity, tidal volume, expiratory reserve volume, inspiratory reserve volume). Results : These findings suggest that supine position in stroke group and control group were significant difference in IC, VC, IRV, ERV(p<.05). $45^{\circ}$ lean sitting position in stroke group and control group were significant difference in IC, VC, ERV(p<.05). 90 sitting position in stroke group and control group were significant difference in VC, IRV, ERV(p<.05). In comparison of two groups, strokes group was more low pulmonary function than normal group. Conclusion : This study showed pulmonary function was more high normal groups than stroke groups. And $90^{\circ}$ sitting position was high pulmonary function than supine position, $45^{\circ}$ lean sitting position. Thus it indicates that the functions will be suggest the objective data of patients with strokes for respiratory function.

Dynamic analysis of non-symmetric FG cylindrical shell under shock loading by using MLPG method

  • Ferezghi, Yaser Sadeghi;Sohrabi, Mohamad R.;MosaviNezhad, Seyed M.
    • Structural Engineering and Mechanics
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    • v.67 no.6
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    • pp.659-669
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    • 2018
  • The Dynamic equations in the polar coordinates are drawn out using the MLPG method for the non-symmetric FG cylindrical shell. To simulate the mechanical properties of FGM, the nonlinear volume fractions for radial direction are used. The shape function applied in this paper is a form of the radial basis functions, by using this function all the requirements for an effective and suitable shape function are established. Hence in this study, the multiquadrics (MQ) radial basis functions are exploited as the shape function governing the problem. The MLPG method is combined with the the Newmark time approximation scheme to solve dynamic equations in the time domain. The obtained results by the MLPG method to be verified are compared with the analytical solution and the FEM. The obtained results through the MLPG method show a good agreement in comparison to other results and the MLPG method has high accuracy for dynamic analysis of the non-symmetric FG cylindrical shell. To demonstrate the capability of the present method to dynamic analysis of the non-symmetric FG cylindrical shell, it is analyzed dynamically with different volume fraction exponents under harmonic and rectangular shock loading. The present method shows high accuracy, efficiency and capability to dynamic analysis of the non-symmetric FG cylindrical shell with nonlinear grading patterns.

Optimal Volume Estimation for Non-point Source Control Retention Considering Spatio-Temporal Variation of Land Surface (지표면의 시공간적 변화를 고려한 비점오염원 저감 저류지 최적용량산정)

  • Choi, Daegyu;Kim, Jin Kwan;Lee, Jae Kwan;Kim, Sangdan
    • Journal of Korean Society on Water Environment
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    • v.27 no.1
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    • pp.9-18
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    • 2011
  • In this study the optimal volume for non-point source control retention is estimated considering spatio-temporal variation of land surface. The 3-parameter mixed exponential probability density function is used to represent the statistical properties of rainfall events, and NRCS-CN method is applied as rainfall-runoff transformation. The catchment drainage area is divided into individual $30m{\times}30m$ cells, and runoff curve number is estimated at each cell. Using the derived probability density function theory, the stormwater probability density function at each cell is derived from the rainfall probability density function and NRCS-CN rainfall-runoff transformation. Considering the antecedent soil moisture condition at each cell and the spatial variation of CN value at the whole catchment drainage area, the ensemble stormwater capture curve is established to estimate the optimal volume for an non-point source control retention. The comparison between spatio-temporally varied land surface and constant land surface is presented as a case study for a urban drainage area.

MIXED VOLUMES OF A CONVEX BODY AND ITS POLAR DUAL

  • Chai, Y. D.;Lee, Young-Soo
    • Bulletin of the Korean Mathematical Society
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    • v.36 no.4
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    • pp.771-778
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    • 1999
  • In this paper, we obtain some geometric inequalities for mixed volumes of a convex body and its polar dual. We also develop a lower bound of the product of quermassintegral of a convex body and its polar dual and give a lower bound for the product of the dual quermassintegral of any index of centrally symmetric convex body and that of its polar dual.

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ROUGH ISOMETRY, HARMONIC FUNCTIONS AND HARMONIC MAPS ON A COMPLETE RIEMANNIAN MANIFOLD

  • Kim, Seok-Woo;Lee, Yong-Han
    • Journal of the Korean Mathematical Society
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    • v.36 no.1
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    • pp.73-95
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    • 1999
  • We prove that if a given complete Riemannian manifold is roughly isometric to a complete Riemannian manifold satisfying the volume doubling condition, the Poincar inequality and the finite covering condition at infinity on each end, then every positive harmonic function on the manifold is asymptotically constant at infinity on each end. This result is a direct generalization of those of Yau and of Li and Tam.

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The Numerical Study on the Cavitation (Cavitation 현상에 관한 수치적 연구)

  • Chang Seonyong;Lee Changjin
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2004.10a
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    • pp.126-131
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    • 2004
  • A numerical code for cavitation is developed based on pressure-based algorithm. The k-\varepsilon$ model (with wall function) is used for turbulence, and volume transport equation is used for cavitation model. The compressibility is not considered for the flow field is low speed.

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Calculation of Stress Intensity Factors Using the Mixed Volume and Boundary Integral Equation Method (혼합 체적-경계 적분방정식법을 이용한 응력확대계수 계산)

  • Lee, Jung-Ki;Lee, Hyeong-Min
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.7
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    • pp.1120-1131
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    • 2003
  • A recently developed numerical method based on a mixed volume and boundary integral equation method is applied to calculate the accurate stress intensity factors at the crack tips in unbounded isotropic solids in the presence of multiple anisotropic inclusions and cracks subject to external loads. Firstly, it should be noted that this newly developed numerical method does not require the Green's function for anisotropic inclusions to solve this class of problems since only Green's function for the unbounded isotropic matrix is involved in their formulation for the analysis. Secondly, this method takes full advantage of the capabilities developed in FEM and BIEM. In this paper, a detailed analysis of the stress intensity factors are carried out for an unbounded isotropic matrix containing an orthotropic cylindrical inclusion and a crack. The accuracy and effectiveness of the new method are examined through comparison with results obtained from analytical method and volume integral equation method. It is demonstrated that this new method is very accurate and effective for solving plane elastostatic problems in unbounded solids containing anisotropic inclusions and cracks.

A Correlation of Testicular Size with Testicular Function in Non-Obstructive Infertile Male (비폐쇄성 남성불임증환자의 고환용적과 고환기능)

  • Myong, Sun-Chul;Kim, In-Gyu;Kim, Sae-Chul
    • Clinical and Experimental Reproductive Medicine
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    • v.18 no.1
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    • pp.107-111
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    • 1991
  • The testicular volume measured by a Prader orchidometer was compared with sperm count in semen, the levels of serum FSH, LH, testosterone, prolactin, estradiol and progesterone in 59 nonobstructive infertile men. 1. The causes of infertility were primary hypogonadisms in 50 patients (35 unknown, 9 Klinefelter syndromes, 6 varicocels) and secondary hypogonadism in 9 (5 isolated FSH deficiencies, 1 hyperprolactinerriia, 3 pituitary hypogonadisms). 2. Decreased levels of serum FSH (less than 4 mIU/ml) did not correlate with testis volume but increased level of serum FSH (more than 20 mIU/ml) were mostly noted in the testis less than 10ml. 3. Decreased level of serum testosterone (less than 3 ng/ml) were distinguishably noted in the atrophied testis less than 5 ml. 4. There was no correlation between the testicular volume and the levels of serum prolactin, estradiol, and progesterone. Coclusively, testicular volume less than 11 ml suggests poor spermatogenesis, but normal testicular volume dose not nessarily rule out poor spermatogenesis. Function of Leydig cell is relatively well preserved in atrophied testis of 5 to 10 ml comparing with that of seminiferous tubule.

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