• Title/Summary/Keyword: volume function

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Optimization of a Pin Fin with inside Fluid (based on Fixed Fin Volume) (내부유체를 가진 Pin Fin의 최적화 (고정된 핀 체적 기준))

  • Kang, Hyung-Suk
    • Journal of Industrial Technology
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    • v.29 no.B
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    • pp.3-7
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    • 2009
  • A cylindrical pin fin with inside fluid is optimized based on fixed fin volume by using the one dimensional analytic method. Heat loss from the fin and the pin fin radius for fixed fin volume is presented as a function of the fin length. Temperature variation of the fin with the variation of ambient and inside fluid convection characteristic numbers and fin base thickness is listed. The maximum heat loss at the practical fin length and corresponding optimum fin length and radius are presented as a function of fin base thickness, inside convection characteristic number, fin volume and ambient convection characteristic number. One of the results shows that the optimum pin fin shape becomes relatively fatter as the fin volume increases.

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Design Method of Multi-Stage Gear Drive (Volume Minimization and Reliability Improvement) (다단 기어장치의 설계법(체적 감소 및 신뢰성 향상))

  • Park, Jae-Hee;Lee, Joung-Sang;Chong, Tae-Hyong
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.16 no.4
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    • pp.36-44
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    • 2007
  • This paper is focused on the optimum design for decreasing volume and increasing reliability of multi-stage gear drive. For the optimization on volume and reliability, multi-objective optimization is used. The genetic algorithm is introduced to multi-objective optimization method and it is used to develop the optimum design program using exterior penalty function method to solve the complicated subject conditions. A 5 staged gear drive(geared motor) is chosen to compare the result of developed optimum design method with the existing design. Each of the volume objective, reliability objective, and volume-reliability multi-objectives are performed and compared with existing design. As a result, optimum solutions are produced, which decrease volume and increase reliability. It is shown that the developed design method is good for multi-stage gear drive design.

NEW TECHNIQUE IN THE USE OF VIBRO-ACOUSTICAL RECIPROCITY WITH APPLICATION TO THE NOISE TRANSFER FUNCTION MEASUREMENT

  • Ko, K.H.;Kook, H.S.;Heo, S.J.
    • International Journal of Automotive Technology
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    • v.7 no.2
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    • pp.173-177
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    • 2006
  • A noise transfer function(NTF) is the frequency response function between an input force applied to an exterior point of a vehicle body and the resultant interior sound pressure usually measured at the driver's ear position. It represents the measure of noise sensitivity for the output force transmitted to the joints between the body and chassis. The principle of vibro-acoustic reciprocity is often utilized in the measurement of NTF. One difficulty in using the volume source is that most of the previously proposed methods require the knowledge of the volume velocity of the acoustic source in advance. A new method proposed in the present work does not require any calculation related with the volume velocity of the acoustic source, but still yields even more accurate results both in the amplitude and phase of the NTF. In the present work, the new method is applied to obtain NTF data for a midsize sedan.

Analysis of the Chest Expansion and Pulmonary Function in the 20s men Obesity according to Position Change (20대 남성 비만인의 자세에 따른 가슴우리 확장과 폐기능 특성분석)

  • Kim, Hyeun-Ae;Seo, Kyo-Chul;Yim, Sang-Yoan;Kim, Hee-Tak;Kim, Kyoung
    • Journal of the Korean Society of Physical Medicine
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    • v.6 no.3
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    • pp.247-256
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    • 2011
  • Purpose : The purpose of this study were to determine whether changes of position might effect the chest expansion and pulmonary function of the 20s men obesity. Methods : Thirty subjects with obesity(M:30, % fat>25.0) and thirty normal subjects(M:30, % fat<24.9) were participated in experiment. Subjects were assessed according to position changes(supine position, $45^{\circ}$ lean sitting position, $90^{\circ}$ sitting position) using chest length(chest length for resting, chest expansion) and pulmonary function (Tidal volume, Inspiratory capacity, Vital capacity, Inspiratory reserve volume, Expiratory reserve volume) by the CardioTouch 3000S(BIONET, USA). Repeated measure ANOVA was used to compare each region data of chest length and pulmonary function according to changes of position with obesity and normal subjects. Results : These findings suggest that the obesity can be appear to low chest expansion and pulmonary function than normal subjects on position method. In comparison of three experimental position, supine position was more low. Conclusion : This study showed position of the obesity appear low chest expansion and function of pulmonary volume than normal subjects, and thus it indicates that the pulmonary function of the obesity will be suggest objective respiratory data through the exercise program.

Moderate hypofractionated image-guided thoracic radiotherapy for locally advanced node-positive non-small cell lung cancer patients with very limited lung function: a case report

  • Manapov, Farkhad;Roengvoraphoj, Olarn;Li, Minglun;Eze, Chukwuka
    • Radiation Oncology Journal
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    • v.35 no.2
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    • pp.180-184
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    • 2017
  • Patients with locally advanced lung cancer and very limited pulmonary function (forced expiratory volume in 1 second $[FEV1]{\leq}1L$) have dismal prognosis and undergo palliative treatment or best supportive care. We describe two cases of locally advanced node-positive non-small cell lung cancer (NSCLC) patients with very limited lung function treated with induction chemotherapy and moderate hypofractionated image-guided radiotherapy (Hypo-IGRT). Hypo-IGRT was delivered to a total dose of 45 Gy to the primary tumor and involved lymph nodes. Planning was based on positron emission tomography-computed tomography (PET/CT) and four-dimensional computed tomography (4D-CT). Internal target volume (ITV) was defined as the overlap of gross tumor volume delineated on 10 phases of 4D-CT. ITV to planning target volume margin was 5 mm in all directions. Both patients showed good clinical and radiological response. No relevant toxicity was documented. Hypo-IGRT is feasible treatment option in locally advanced node-positive NSCLC patients with very limited lung function ($FEV1{\leq}1L$).

The Effect of Dynamic Neuromuscular Stabilization (DNS) on the Respiratory Function of Subjects with Forward Head Posture (FHP)

  • Bae, Won-Sik
    • Journal of the Korean Society of Physical Medicine
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    • v.16 no.3
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    • pp.55-64
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    • 2021
  • PURPOSE: The purpose of this study was to apply dynamic neuromuscular stabilization (DNS) to subjects with forward head posture (FHP) and to compare its effects on respiratory function as against the conventional neck stabilization exercise and neck stretching and extensor strengthening exercises. METHODS: The whole-body posture measurement system was used to measure the degree of FHP, and a spirometer and a respiratory gas analyzer were used to measure the respiratory function. After the intervention was completed, the changes over time were analyzed in the DNS group, the neck stabilization exercise group, and the neck stretching and extensor strengthening exercise group. The inter-group difference in the changes was also analyzed. A repeated ANOVA was performed to compare the respiratory function according to the period between the three groups, and the least significant difference (LSD) method was used for the post hoc test. RESULTS: After the 6-week exercise period, respiratory functions, such as forced vital capacity (FVC), forced expiratory volume for 1 second (FEV1), forced expiratory volume for 1 sec/forced vital capacity (FEV1/FVC), maximum oxygen intake (VO2max), and the volume of expired gas (VE), significantly improved according to the period (p < .05), but no inter-group differences were found. CONCLUSION: DNS is an effective training method, and can be applied along with neck stabilization exercise and neck stretching and extensor strengthening exercises, which are widely used in clinical practice, to people with FHP who cannot directly perform neck exercises to improve their respiratory function.

Prediction of Radiative Heat Transfer in a Three-Dimensional Gas Turbine Combustor with the Finite-Volume Method (유한체적법에 의한 복잡한 형상을 갖는 3차원 가스터빈 연속기내의 복사열 전달 해석)

  • Kim, Man-Yeong;Baek, Seung-Uk
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.20 no.8
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    • pp.2681-2692
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    • 1996
  • The finite-volume method for radiation in a three-dimensional non-orthogonal gas turbine combustion chamber with absorbing, emitting and anisotropically scattering medium is presented. The governing radiative transfer equation and its discretization equation using the step scheme are examined, while geometric relations which transform the Cartesian coordinate to a general body-fitted coordinate are provided to close the finite-volume formulation. The scattering phase function is modeled by a Legendre polynomial series. After a benchmark solution for three-dimensional rectangular combustor is obtained to validate the present formulation, a problem in three-dimensional non-orthogonal gas turbine combustor is investigated by changing such parameters as scattering albedo, scattering phase function and optical thickness. Heat flux in case of isotropic scattering is the same as that of non-scattering with specified heat generation in the medium. Forward scattering is found to produce higher radiative heat flux at hot and cold wall than backward scattering and optical thickness is also shown to play an important role in the problem. Results show that finite-volume method for radiation works well in orthogonal and non-orthogonal systems.

The effect of Corni Fructus on renal function

  • Jeong, Myung-Kum;Yang, Ki-Sook
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.385.2-385.2
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    • 2002
  • Cornus officinalis has been used as protective drug for liver and kidney function. In order to evaluate the effect on renal function of Corni Fructus. We measured urine volume, chemical parameters(urea nitrogen. creatinine, uric acid). electrolytes($Na^{+}$, $K^{+}$, $Cl^{-}$) in serum and urine. Furosemide showed significant urine volume. serum and urine parameters, but Corni Fructus showed normal level parameters by dose increasing in rats.

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A Study on the Effect of Time Lapse After Position Change and Abdominal Band on Pulmonary Function in the Cervical Cord Injuries (척수손상 환자의 자세 변화 후 시간경과와 복대사용이 폐기능에 미치는 영향)

  • Lee, Jae-Ho;Park, Chang-Il;Chon, Joong-Sun
    • Physical Therapy Korea
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    • v.4 no.3
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    • pp.17-33
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    • 1997
  • The objective of this study was to identify pulmonary functional variations in relation to postural changes, lapse after changing position, and the use of abdominal band in the cervical cord injured. The subjects of this study were 19 quadriplegic patients who had been admitted to the department of the Rehabilitation Hospital, College of Medicine, Yousei University, from April, 1997 through May 3, 1997. A spiroanalyzer was used to measure pulmonary function in supine, standing, time after changing position, and recording to the position, application method, and tightness of the abdominal band. The data were analyzed by the repeated measure one-way ANOVA, and Wilcoxon signed rank test. The findings were as follows: 1. All phase of the patients' pulmonary function improved significantly in supine posture in contrast to standing (vital capacity by $0.46{\ell}$ and expiratory reserve volume by $0.09{\ell}$). 2. The longer the time lapsed from supine posture to standing, the patient's expiratory reserve volume, maximum ventilation volume, vital capacity, and forced expiratory volume increased. 3. When the patient lay in supine position, the maximum ventilation volume, vital capacity, and the forced vital capacity increased then the center line of the abdominal band was placed along iliac crest; on the other hand, when the patient was standing, placing the bottom line of the abdominal band along iliac crest increased the maximum ventilation volume, vital capacity, and forced expiratory volume. 4. In placing the abdominal band in the patients, leaving space between the top and bottom lines of the band helped increased in maximum ventilation volume, vital capacity, and forced vital capacity for patient in supine as well as in standing. 5. When placing the abdominal band to patients in supine posture, reducing the length of the band by 2.5% along the patient's waist line increased the patients' vital capacity, while reducing the length by 10% to patients in standing increased the maximum ventilation volume. The abdominal band should be placed in such a way that the bottom part of the band should be more tightly fastened while leaving enough room for a hand to be placed in between the body and the band for the top part of the hand. It should also be noted that in a supine position, the bottom line of the band should be placed along the iliac crest, while in standing, the center line should be placed along the iliac crest. The length of the band should also be reduced by 2.5% of the waist line in supine position, and in standing, the length should be reduced by 10%. It should also be noted that the pulmonary function of the patients should be measured at least 10 minutes after one position change.

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Effects of vasopressin administration in the oral cavity on cardiac function and hemodynamics in rats

  • Fukami, Hayato;Sunada, Katsuhisa
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.22 no.1
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    • pp.11-18
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    • 2022
  • Background: The vasoconstrictive effect of epinephrine in local anesthetics affects the heart, which leads to hesitation among dentists in injecting local anesthetics into patients with cardiovascular disease. Due to its vasoconstrictive effects, the present study investigated the effects of vasopressin administration on cardiac function in rats. Methods: Experiment 1 aimed to determine the vasopressin concentration that could affect cardiac function. An arterial catheter was inserted into the male Wistar rats. Next, 0.03, 0.3, and 3.0 U/mL arginine vasopressin (AVP) (0.03V, 0.3V, and 3.0V) was injected into the tongue, and the blood pressure was measured. The control group received normal saline only. In Experiment 2, following anesthesia infiltration, a pressure-volume catheter was placed in the left ventricle. Baseline values of end-systolic elastance, end-diastolic volume, end-systolic pressure, stroke work, stroke volume, and end-systolic elastance were recorded. Next, normal saline and 3.0V AVP were injected into the tongue to measure their effect on hemodynamic and cardiac function. Results: After 3.0V administration, systolic blood pressures at 10 and 15 min were higher than those of the control group; they increased at 10 min compared with those at baseline. The diastolic blood pressures at 5-15 min were higher than those of the control group; they increased at 5 and 10 min compared with those at baseline. The preload decreased at 5 and 10 min compared to that at baseline. However, the afterload increased from 5 to 15 min compared with that of the control group; it increased at 10 min compared with that at baseline. Stroke volume decreased at 10 and 15 min compared with that of the control group; it decreased from 5 to 15 min compared with that at baseline. Stroke work decreased from 5 to 15 min compared with that of the control group; it decreased from 5 to 15 min compared with that at baseline. Conclusion: Our results showed that 3.0 U/mL concentration of vasopressin resulted in increased blood pressure, decreased stroke volume and stoke work, decreased preload and increased afterload, without any effect on myocardial contractility.