• Title/Summary/Keyword: Partial volume effect

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The effect of aprotinin for hemostasis in open heart surgery (개심술시 Aprotinin의 지혈효과에 대한 고찰)

  • 홍민수
    • Journal of Chest Surgery
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    • v.26 no.10
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    • pp.749-752
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    • 1993
  • The 26 patients were randomly selected among patients who underwent valve replacement from February 1992 through September 1993 at National Medical Center. They were divided into two groups, one control group[n=13], the other aprotinin group[n=13]. The aprotinin group recieved 15000 KIU/kg aprotinin in the CPB priming volume and 35000 KIU/kg aprotinin intravenously during operation. We checked preoperative and postoperative hemoglobin, platelet, prothrombin time, activated partial thromboplastin time, creatinine phosphokinase and lactic dehydrogenase. There was no difference in the patient`s above clinical parameters between both groups. The platelet count in both groups decreaced after operation. These findings demonstrated that the effectiveness of aprotinin was not associated with platelet number but probably associated with a protection of platelet function and a prevention of hyperfibrinolysis. The intraoperative and postoperative blood loss and requirement of blood were significantly reduced in aprotinin group.

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A Study on the Sensory and Texture Characteristics of Bread with Roasted Soybean Powder (볶은 콩가루 첨가량을 달리하여 제조한 식빵의 관능적 기계적 특성 연구)

  • 정해옥;임상선;정복미
    • Korean journal of food and cookery science
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    • v.13 no.3
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    • pp.266-271
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    • 1997
  • The effect of partial replacement of flour with roasted soybean powder (0, 5, 10, 15, 20%) was examined by sensory and instrumental analyses of the bread. There were no significant changes in specific loaf volume up to 10% of replacement. Although the hardness of the bread increased with increasing storage time at higher replacement, there were no differences in springiness and cohesiveness compared with control. The yellow color of the soybean powder was reflected in the bread, however, it did not affect the preference. Overall, the bread with 10-15% soybean powder suggested to be acceptable.

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The investigation of Magnetohydrodynamic nanofluid flow with Arrhenius energy activation

  • Sharif, Humaira;Khadimallah, Mohamed A.;Naeem, Muhammad Nawaz;Hussain, Muzamal;Mahmoud, S.R.;Al-Basyouni, K.S.;Tounsi, Abdelouahed
    • Advances in nano research
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    • v.10 no.5
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    • pp.437-448
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    • 2021
  • In this article, an analytically and numerically 3D nanoliquid flow by a porous rotatable disk is presented in the presence of gyrotactic microorganisms. The mathematical model in the form of partial differential system is transmuted into dimensionless form by utilizing the appropriate transformation. The homotopy analysis approach is applied to attain the analytic solution of the problem. The effect of promising parameters on velocity distribution, temperature profile, nanoparticles volume fraction and motile microorganism distribution field are evaluated through graphs and in tabular form. The existence of Brownian motion and thermophoresis impacts are more proficient for heat transfer enhancement. Further the unique features like heat absorption/generation and energy activation are also examined for the present flow problem. The obtained results are compared with the earliear investigation to check the accuracy of present model.

Nonlinear oscillations of a composite microbeam reinforced with carbon nanotube based on the modified couple stress theory

  • M., Alimoradzadeh;S.D., Akbas
    • Coupled systems mechanics
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    • v.11 no.6
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    • pp.485-504
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    • 2022
  • This paper presents nonlinear oscillations of a carbon nanotube reinforced composite beam subjected to lateral harmonic load with damping effect based on the modified couple stress theory. As reinforcing phase, three different types of single walled carbon nanotubes distribution are considered through the thickness in polymeric matrix. The non-linear strain-displacement relationship is considered in the von Kármán nonlinearity. The governing nonlinear dynamic equation is derived with using of Hamilton's principle.The Galerkin's decomposition technique is utilized to discretize the governing nonlinear partial differential equation to nonlinear ordinary differential equation and then is solved by using of multiple time scale method. The frequency response equation and the forced vibration response of the system are obtained. Effects of patterns of reinforcement, volume fraction, excitation force and the length scale parameter on the nonlinear responses of the carbon nanotube reinforced composite beam are investigated.

Use of Adaptive Meshes in Simulation of Combustion Phenomena

  • Yi, Sang-Chul;Koo, Sang-Man
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1996.06b
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    • pp.285-309
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    • 1996
  • Non oxide ceramics such as nitrides of transition metals have shown significant potential for future economic impact, in diverse applications in ceramic, aerospace and electronic industries, as refractory products, abrasives and cutting tools, aircraft components, and semi-conductor substrates amid others. Combustion synthesis has become an attractive alternative to the conventional furnace technology to produce these materials cheaply, faster and at a higher level of purity. However he process os highly exothermic and manifests complex dynamics due to its strongly non-linear nature. In order to develop an understanding of this process and to study the effect of operational parameters on the final outcome, numerical modeling is necessary, which would generated essential knowledge to help scale-up the process. the model is based on a system of parabolic-hyperbolic partial differential equations representing the heat, mass and momentum conservation relations. The model also takes into account structural change due to sintering and volumetric expansion, and their effect on the transport properties of the system. The solutions of these equations exhibit steep moving spatial gradients in the form of reaction fronts, propagating in space with variable velocity, which gives rise to varying time scales. To cope with the possibility of extremely abrupt changes in the values of the solution over very short distances, adaptive mesh techniques can be applied to resolve the high activity regions by ordering grid points in appropriate places. To avoid a control volume formulation of the solution of partial differential equations, a simple orthogonal, adaptive-mesh technique is employed. This involves separate adaptation in the x and y directions. Through simple analysis and numerical examples, the adaptive mesh is shown to give significant increase in accuracy in the computations.

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A Study of Total Dose in Intensity Modulation Radiation Therapy (선량강도 조절법을 이용한 방사선치료에서 총선량에 관한 고찰)

  • 김성규
    • Progress in Medical Physics
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    • v.11 no.1
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    • pp.85-90
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    • 2000
  • In radiation therapy, the effects of radiation are decided total dose, total treatment times and number of radiation dose fractions. We considered that total dose, total treatment times and number of radiation dose fractions in intensity modulation radiation therapy(IMRT) infuence tumor cell killing. The goal of three dimensional conformal radiation therapy(3DCRT) in radiation therapy is to conform the partial distribution of the prescribed radiation dose to the precise 3D configuration of the tumor, and at the same time, to minimize the dose to the surrounding normal tissues. To optimize treatment volume of tumor, treatment volume will be same tumor volume. All IMRT compare to conventional treatment plus boost IMRT when total dose irradiated 75 - 90 Gy. Because of biological effect, total dose are decreased 12.5 - l5Gy in all IMRT.

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An experimental and analytical study into the strength of hooked-end steel fiber reinforced HVFA concrete

  • Shariq, M.;Pal, S.;Chaubey, R.;Masood, A.
    • Advances in concrete construction
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    • v.13 no.1
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    • pp.35-43
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    • 2022
  • The experimental investigations into hooked-end round steel fibers (HSF) effect on the age-dependent strengths of high volume fly ash (HVFA) concrete is studied. The concrete was prepared with class F fly ash used as partial cement replacement varied from 0% to 70% on an equal weight basis. Two percentages of HSF (i.e., 0.5% and 1.5% by volume fraction) of 50 mm length were added in plain, and 50% fly ash concrete mixes. The compressive and flexural tensile strength was determined at 7, 28, 56, and 90 days. The strength results of fly ash concrete mixes with and without steel fibers were compared with the plain concrete strength. The test results indicated that the strength of fly ash concrete is comparable with the plain concrete strength and further increases with an increase in the percentage of steel fibers. The maximum flexure strength of HVFA concrete is found with 0.5% steel fibers. It is concluded that the HVFA concrete with steel fibers of 50 mm length can effectively be used in concrete construction. The analytical models are proposed to predict the age-dependent compressive and flexural tensile strength of HVFA concrete with and without HSF. The compressive and tensile strength of HVFA concrete with HSF can be predicted using these models when the 28-day compressive strength of plain concrete is known. The present study will be helpful in the design and construction of reinforced and pre-stressed concrete structures made with HVFA and HSF.

A study of an oyster monthly forecasting model using the structural equation model approach based on a panel analysis

  • Sukho Han;Seonghwan Song;Sujin Heo;Namsu Lee
    • Korean Journal of Agricultural Science
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    • v.49 no.4
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    • pp.949-961
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    • 2022
  • The purpose of this study is to build an oyster outlook model. In particular, by limiting oyster items, it was designed as a partial equilibrium model based on a panel analysis of a fixed effect model on aquaculture facilities. The model was built with a dynamic ecological equation (DEEM) system that considers aquaculture and harvesting processes. As a result of the estimation of the initial aquaculture facilities based on the panel analysis, the elasticity of the remaining facility volume in the previous month was estimated to be 0.63. According to Nerlove's model, the adjustment coefficient was interpreted as 0.31 and the adjustment speed was analyzed to be very slow. Also, the relative income coefficient was estimated to be 2.41. In terms of elasticity, it was estimated as 0.08% in Gyeongnam, 0.32% in Jeonnam, and 1.98% in other regions. It was analyzed that the elasticity of relative income was accordingly higher in non-main production area. In case of the estimation of the monthly harvest facility volume, the elasticity of the remaining facility volume in the previous month was estimated as 0.53, and the elasticity of the farm-gate price was estimated as 0.23. Both fresh and chilled and frozen oysters' exports were estimated to be sensitive to fluctuations in domestic prices and exchange rates, while Japanese wholesale prices were estimated to be relatively low in sensitivity, especially to the exchange rate with Japan. In estimating the farm-gate price, the price elasticity coefficient of monthly production was estimated to be inelastic at 0.25.

The Effect of Lipo-PGE1 on the Viability of Injected Adipose Tissue on Mouse Model (Lipo-PGE1이 이식된 지방 생존에 미치는 영향)

  • Oh, Eui-Sun;Jung, Ji-Eun;Lew, Dae-Hyun
    • Archives of Plastic Surgery
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    • v.37 no.5
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    • pp.526-530
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    • 2010
  • Purpose: With the recent recognition of the importance of soft-tissue fillers, fat grafting has been assumed an increasingly important role as both an adjunctive and a primary procedure in aesthetic and reconstructive surgery. The main problem in achieving long-term soft-tissue augmentation is partial absorption of the injected fat and hence the need for overcorrection and re-injection. The purpose of this study is to improve the viability of the injected fat by the use of Lipo-PGE1. Methods: Human adipose tissue, obtained by suctionassisted lipectomy, was re -injected into the subcutaneous layer in the scalp of ICR mice. Lipo-PGE1 ($0.5{\mu}g$/kg) was injected intravenously in experimental group for 7 days from the operation day and saline was injected in control group. There were 5 animals in each group. The animals were euthanized 4 weeks after the procedure. Graft weight and volume were measured and histologic evaluation was performed. Result: Histologic analysis demonstrated significantly less cyst formation and less inflammatory reaction in the group treated with Lipo-PGE1. No significant difference was found between the groups regarding graft volume or the other histologic parameters investigated. Significant differences were demonstrated in microvascular density count. Conclusion: Less cyst formation, less inflammation, more angiogenesis indicating improved quality of the injected fat can be obtained by the addition of Lipo-PGE1. Further studies of various dosages of Lipo-PGE1 and their long-term effect are required before these encouraging results could be applied clinically.

THE EFFECT OF MONOMER TO POWDER RATIO ON POLYMERIZATION SHRINKAGE-STRAIN KINETICS OF POLYMER-BASED PROVISIONAL CROWN AND FIXED PARTIAL DENTURE MATERIALS

  • Kim, Sung-Hun
    • The Journal of Korean Academy of Prosthodontics
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    • v.45 no.6
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    • pp.735-742
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    • 2007
  • Statement of problem. Although a number of previous investigations have been carried out on the polymerization shrinkage-strain kinetics of provisional crown and fixed partial denture (FPD) materials, the effect of the changes of liquid monomer to powder ratio on its polymerization shrinkage-strain kinetics has not been reported. Purpose. The purpose of this study was to investigate the influence of liquid monomer to powder ratio of polymer-based provisional crown and FPD materials on the polymerization shrinkage-strain kinetics. Material and methods. Chemically activated acrylic provisional materials (Alike, Jet, Snap) were investigated. Each material was mixed with different liquid monomer to powder ratios by volume (1.0:3.0, 1.0:2.5, 1.0:2.0, 1.0:1.5, 1.0:1.0). Time dependent polymerization shrinkage- strain kinetics of all materials was measured by the bonded-disk method as a function of time at $23^{\circ}C$. Five recordings were taken for each ratio. The results were statistically analyzed using one-way ANOVA and the multiple comparison Scheffe test at the significance level of 0.05. Trends were also examined by linear regression. Results. At 5 minutes after mixing, the polymerization shrinkage-strains of all materials ranged from only 0.01% to 0.49%. At 10 minutes, the shrinkage-strain of Alike was the highest, 3.45% (liquid monomer to powder ratio=1.0:3.0). Jet and Snap were 2.69% (1.0:2.0) and 1.58% (1.0:3.0), respectively (P>0.05). Most shrinkage (94.3%-96.5%) occurred at 30 minutes after mixing for liquid monomer to powder ratio, ranging from 1.0:3.0 to 1.0:1.0. The highest polymerization shrinkage-strain values were observed for the liquid monomer to powder ratio of 1.0:3.0. At 120 minutes after mixing, the shrinkage-strain values were 4.67%, 4.18%, and 3.07% for Jet, Alike, and Snap, respectively. As the liquid monomer to powder ratio increased, the shrinkage-strain values tend to be decreased linearly (r=-0.769 for Alike, -0.717 for Jet, -0.435 for Snap, $r^2=0.592$ for Alike, 0.515 for Jet, 0.189 for Snap; P<0.05). Conclusion. The increase of the liquid monomer to powder ratio from 1.0:3.0 to 1.0:1.0 had a significant effect on the shrinkage-strain kinetics of polymer-based crown and FPD materials investigated. This increased the working time and decreased the shrinkage-strain during polymerization.