• Title/Summary/Keyword: Volume Curve

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Estimating the Stand Structure Index Based on Lorenz Curve (Lorenz곡선(曲線)에 근거(根據)한 임분구조지수추정(林分構造指數推定))

  • Lee, Woo-Kyun
    • Journal of Korean Society of Forest Science
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    • v.86 no.2
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    • pp.158-166
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    • 1997
  • This study presents the method to quantify the stand structure diversity or homogeneity. Gadow's dbh differentiation(Durchmesserdifferenzierung) is introduced which quantifies the horizontal stand structure by the ratio of the dbh between subject tree and neighbour trees. And new stand structure diversity index based on Lorenz curve, which is made by ratio of tree number and basal area or volume by dbh class, is presented. The horizontal stand structure index based on Lorenz curve has a value from 0 to 1 as Gadow's index, and approximates to 1 if the stand structure has high diversity. In the comparative analysis for performance, the new stand structure index based on Lorenz curve is considered to compare with the Gadow's index for describing the stand structure.

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Revised AMC for the Application of SCS Method (SCS 유효우량 산정방법 적용을 위한 선행토양함수조건의 재설정(장평유역을 중심으로))

  • Park, Cheong-Hoon;Yoo, Chul-Sang;Kim, Joong-Hoon
    • Proceedings of the Korea Water Resources Association Conference
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    • 2005.05b
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    • pp.578-582
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    • 2005
  • In this study, the conceptual foundation and development process of the Antecedent soil Moisture Condition(AMC) in SCS runoff curve number method are reviewed. Although the runoff volume is very sensitive with AMC condition, the AMC class limits developed in SCS(1972) are used in rainfall-runoff analysis without careful consideration. Tn this study, following the SCS curve number development process, rainfall-runoff characteristics of the Jang-Pyung subbasin subject to the Pyung-Chang River basin are analyzed to evaluate the reasonability of the AMC class limits at present. The New AMC class limits are proposed by the sensitive analysis of the antecedent rainfall - curve number value. As a result, the classification value of AMC-I with II is 22mm of antecedent 5-day rainfall amount, and the classification of AMC-II with III is 117mm in growing season. When the New AMC class limits are applied to Jang-Pyung subbasin, AMC probability distribution shows that the AMC-II has increased remarkably even though the AMC-I has a little higher value. But the AMC-III has the smallest one. According to the conceptual basis of the curve number method, the AMC probability distribution, the New AMC class limits adopted, gives reasonable results.

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On the Volumetric Balanced Variation of Ship Forms (체적 밸런스 선형변환방법에 대한 연구)

  • Kim, Hyun-Cheol
    • Journal of Ocean Engineering and Technology
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    • v.27 no.2
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    • pp.1-7
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    • 2013
  • This paper aims at contributing to the field of ship design by introducing new systematic variation methods for ship hull forms. Hull form design is generally carried out in two stages. The first is the global variation considering the sectional area curve. Because the geometric properties of a sectional area curve have a decisive effect on the global hydrodynamic properties of ships, the design of a sectional area curve that satisfies various global design conditions, e.g., the displacement, longitudinal center of buoyancy, etc., is important in the initial hull form design stage. The second stage involves the local design of section forms. Section forms affect the local hydrodynamic properties, e.g., the local pressure in the fore- and aftbody. This paper deals with a new method for the systematic variation of sectional area curves. The longitudinal volume distribution of a ship depends on the sectional area curve, which can geometrically be controlled using parametric variation and a variation that uses the modification function. Based on these methods, we suggest a more generalized method in connection with the derivation of the lines for a new design compared to those for similar ships. This is the so-called the volumetric balanced variation (VOB) method for ship forms using a B-spline modification function and an optimization technique. In this paper the global geometric properties of hull forms are totally controlled by the form parameters. We describe the new method and some application examples in detail.

Effect of thoracic cage mobilization on respiratory function, spinal curve and spinal movement in patients with restrictive lung disease

  • Wang, Joong San
    • Journal of International Academy of Physical Therapy Research
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    • v.7 no.2
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    • pp.1006-1010
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    • 2016
  • This study aimed to examine the effects of thoracic cage mobilization on the respiratory function, spinal curve and spinal movement in patients with restrictive lung diseases. The subjects were ten community-dwelling elderly with a restrictive lung diseases when measured using a spirometer($FEV1/FVC{\leq}65%$, FVC<80%). They received an intervention over an eight-week period: three times a week and for 30 minutes a day. SPSS for Windows(ver. 19.0) was used to analyze all the collected data. Independent t-tests were used to examine changes before and after the intervention. The study's results showed statistically significant improvement(p<.05) in forced expiratory volume in 1 second(chage rate: .$24{\pm}.25$), thoracic curve(chage rate: $-2.50{\pm}2.76$), lumbar curve(chage rate: $-.80{\pm}1.32$), thoracic flexion(chage rate: $2.10{\pm}1.52$), thoracic extension(chage rate: $-2.00{\pm}1.25$), lumbar flexion(chage rate: $2.40{\pm}3.13$) and lumbar extension(chage rate: $-1.30{\pm}1.42$). The results of this study suggest that the thoracic cage mobilization contribute to improve pulmonary function in patients with restrictive lung disease.

Transabdominal Ultrasound Assessment of the Polycystic Ovary Syndrome (다낭난소증후군 진단시 복식 초음파의 유용성에 관한 연구)

  • Jeong, Kyung-Ah;Lee, Woon-Jeong;Chung, Hye-Won
    • Clinical and Experimental Reproductive Medicine
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    • v.36 no.4
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    • pp.255-263
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    • 2009
  • Objective: The objective of the study was to determine the diagnostic performance of transabdominal ultrasound by receiver operating characteristic (ROC) curve analysis, in order to evaluate the usefulness in establishing the diagnosis of polycystic ovary syndrome (PCOS). Methods: Questionnaires were given to 8,793 reproductive women reviewed at Ewha Womans University Mokdong hospital. Ultrasound examinations were performed in 701 women with a transabdominal transducer. Transabdominal ultrasounds were performed in 185 normal control women (normal menstruation without hyperandrogenism or PCO morphology) and 248 PCOS patients according to National Institutes of Health (NIH) PCOS diagnosis criteria. ROC curves were calculated for ovarian volume and follicle number. Results: In normal control group, the mean age were $23.64{\pm}4.26$ years old and the mean ovarian volume and follicle number were $6.03{\pm}1.89\;cm^3$ and $6.49{\pm}1.93$, respectively. The ovarian volume showed an area under the ROC curve (AURC) of 0.761. A ovarian volume decision threshold >$9\;cm^3$ had a sensitivity of 51.0% and a specificity of 91.4% for the diagnosis of PCOS. The follicle number showed an AURC of 0.733. A follicle number decision threshold ${\geq}9$ had a sensitivity of 54.9% and a specificity of 87.0% for the diagnosis of PCOS. A follicle number decision threshold ${\geq}10$ had a sensitivity of 53.2% and a specificity of 90.4%. A follicle number and a ovarian volume did not have a high diagnostic power for screening for PCOS. Conclusion: Our results suggest that transabdominal ultrasound assessment is not effective for the detection of PCOS in young women of reproductive age.

Development of Stem Analysis Program(Stemwin1.0) for Windows (Windows용 수간석해(樹幹析解) 프로그램(Stemwin1.0)의 개발(開發))

  • Lee, Joon-Hak;Lee, Woo-Kyun;Seo, Jeong-Ho
    • Journal of Korean Society of Forest Science
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    • v.90 no.3
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    • pp.331-337
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    • 2001
  • This study was performed to develope stem analysis program(Stemwin1.0) which can be used in PC with MS-Windows operating system. Stemwin1.0 uses width of annual tree ring measured with 1/100mm unit, and calculate increments of several growth factors such as DBH, height and volume with various methods. Mean DBH can be calculated by arithmetic and quadratic mean methods. Height can be estimated by parallel line, line extending and height curve methods. Volume can be estimated by Huber, Smalian, and Spline functions. Not only Total growth, Mean Annual Increment(MAI) and Current Annual Increment(CAI) of growth factors, but also merchantable volume and height, form factor, growth rate, and merchantable volume rate are automatically calculated. Stemwin1.0 can also output accurate stem taper curve with various scale, and prepare stem taper data(diameter at different disk heights) for statistical analysis for deriving stem taper model. Stemwin1.0 can export output data and graph to Excel for more compatible use of it.

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Effect of Betamethasone on the Pulmonary Pressure-Volume Curve in Unilateral Pneumonectomized Rabbits (Betamethasone이 일측폐장절제 가토폐장의 압력-용적곡선에 미치는 영향)

  • Lee, Young-Man;Lee, Suck-Kang
    • The Korean Journal of Physiology
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    • v.17 no.1
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    • pp.23-28
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    • 1983
  • In order to clarify the effect of steroid on the pulmonary pressure-volume curve in the pneumonectomized rabbit, the right side pneumonectomy was performed under general anesthesia with pentobarbital sodium and the remaining lung was excised on the fifth day after surgery. The intrapulmonic pressure in the excised left lung was measured at 20, 25, and 30 ml lung volume during inflation and deflation period. In the steroid treated group, the intrapulmonic pressure at 20, 25, and 30 ml lung volume during inflation was significantly decreased compared with intrapulmonic pressure of the control group. But in the pneumonectomy group the decreasing tendency of the pressure was observed. During deflation, the intrapulmonic pressure at 25 ml and 20 ml was not significantly different from the control group in pneumonectomy and steroid treated pneumonectomy group. And the lung weight was measured in each experimental group and also the lung weightbody weight ratio(L/B) was calculated. The lung weight was significantly increased in both pneumonectomy and steroid treated pneumonectomy group. Calculated L/B was increased significantly in both group. Above results suggest that steroid increases the secretion of pulmonary surfactant or affects the catabolic effect on protein metabolism of connective tissue in lung parenchyma.

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Numerical Study of Forced Convection Nanofluid in a U-Bend Tube (U-밴드 관 내부 나노유체의 강제대류에 관한 수치적 연구)

  • Jo, Sung-Won;Choi, Hoon-Ki;Park, Yong-Gap
    • Journal of Convergence for Information Technology
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    • v.12 no.3
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    • pp.141-150
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    • 2022
  • Fluid flow and thermal characteristics of laminar nanofluid(water/Al2O3) flow in a circular U-bend tube have been studied numerically. In this study, the effect of Reynolds number and the solid volume fraction and the impact of the U-bend on the flow field, the heat transfer and pressure drop was investigated. Comparisons with previously published experimental works on horizontal curved tubes show good agreements between the results. Heat transfer coefficient increases by increasing the solid volume fraction of nanoparticles as well as Reynolds number. Also, the presence of the secondary flow in the curve plays a key role in increasing the average heat transfer coefficient. However, the pressure drop curve increases significantly in the tubes with the increase in nanoparticles volume fraction.

The development of engine analyzer (엔진아나라이져의 개발)

  • 이재순;임성식;이용규
    • Journal of the korean Society of Automotive Engineers
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    • v.11 no.6
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    • pp.89-96
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    • 1989
  • Engine analyzer is developed with the aids of personal computer, A/D converter, interfacing signal transducer and data processing computer programs. The objective of this development are that it should firstly be produced at the resonable low price compared with imported one taking advantage of using existing personal computer and printer, and it should also give good quality of performance. For the attainment of this objective, A/D converter should have been developed to meet the price limit of the equipment. The experiment is performed in a 4 cycle 4 cylinder gasoline engine by this analyzer, and all the information which are necessary for the combustion analysis can be obtained through the processing of the pressure data that are stored in the computer. These are pressure-volume curve, pressure-crank angle curve, the rate of pressure rise and heat release versus crank angle curve etc. With this developed experimental system of resonable price, it will be considered that more easy way of engine data pick-up and processing is possible.

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The Effects of Resin Ratio and Bed Depth on the Performance of Mixed-bed Ion Exchange at Ultralow Solution

  • Yoon, Tae-Kyung;Lee, Gang-Choon;Noh, Byeong-Il
    • Journal of Environmental Science International
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    • v.18 no.6
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    • pp.595-601
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    • 2009
  • The effects of the cation-to-anion resin ratio and bed depth on ion exchange performance of mixed-bed were studied at ultralow solution concentration. Breakthrough curves were experimentally obtained for NaCI solution as functions of resin ratio and bed depth. The bed depth affects the pattern of the sodium breakthrough curve but not the chloride breakthrough curve in beds because of the selectivity difference. Resin selectivity determines the shape of breakthrough curves, Some sodium and chloride breakthrough curves crossed at a point as a function of resin ratio. The lower cation-to-anion resin ratio showed the higher effluent concentration or treated volume of the crossover point regardless of the total resin weight.