• Title/Summary/Keyword: kinetic models

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The study of the possibility Emergency Landing for LSA in Marado (마라도에서의 경량항공기 비상착륙 가능성에 대한 연구)

  • Shin, Dai-Won;Lee, Gi-Moung
    • Journal of the Korean Society for Aviation and Aeronautics
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    • v.24 no.3
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    • pp.19-25
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    • 2016
  • In this study, we surveyed the Marado status of the availability of emergency runway for the LSA, through site visits. For the future progress Marado flight tour operation, for LSA of 4 models with respect to just in case there was an emergency situation analysis of the availability of emergency runway. We analyzed the problems of the sloping runway with the changing elements for the kinetic and potential energy. The Bingo and CH-650 models of LSA are usability emergency runway of Marado for take-off and landing. But the AT-4 and CTLS models of LSA are limited or impossible to use emergency runway of the Marado.

Study on the numerical models of turbulent dispersion of solid particles in a two-phase turbulent jet flow (이상난류제트 유동에서 고체입자 난류확산의 수치모델에 관한 연구)

  • 양선규;최영돈
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.11 no.1
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    • pp.1-18
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    • 1987
  • Prediction performances by Einstein's equation of diffusivity, Peskin's model, Three-Equation model, Four-Equation model and Algebraic Stress Model, have been compared by analyzing twophase (air-solid) turbulent jet flow. Turbulent kinetic energy equation of dispersed phase was solved to investigate effects of turbulent kinetic energy on turbulent diffusivity. Turbulent kinetic energy dissipation rate of particles has been considered by solving turbulent kinetic energy dissipation rate equation of dispesed phase and applying it to turbulent diffusivity of dispersed phase. Results show that turbulent diffusivity of dispersed phase can be expressed by turbulent kinetic energy ratio between phases and prediction of turbulent kinetic energy was improved by considering turbulent kinetic energy dissipation rate of dispersed phase for modelling turbulent diffusivity. This investigation also show that Algebraic Stress Model is the most promising method in analyzing gas-solid two phaes turbulent flow.

Evaluation of Bacterial Transport Models for Saturated Column Experiments

  • Ham, Young-Ju;Kim, Song-Bae;Kim, Min-Kyu;Park, Seong-Jik
    • Journal of The Korean Society of Agricultural Engineers
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    • v.48 no.7
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    • pp.55-63
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    • 2006
  • Bacterial transport models were evaluated in this study to determine the suitable model at describing bacterial transport in saturated column experiments. Four models used in the evaluation were: advective-dispersive equation (ADE) + equilibrium sorption/retardation (ER) + kinetic reversible sorption (KR) (Model I), ADE + two-site sorption (Model 2), ADE + ER + kinetic irreversible sorption (KI) (Model 3), ADE + KR + KI (Model 4). Firstly, analyses were performed with the first experimental data, showing that Model 4 is appropriate for describing bacterial transport. Even if Model 1 and 2 fit well to the observed data, they have a defect of not including the irreversible sorption, which is directly related to mass loss of bacteria. Model 3 can not properly describe the tailing observed in the data. However, further analysis with the second data indicates that Model 4 can not describe retardation of bacteria, even if the sorption-related parameters are varied. Therefore, Model 4 is modified by incorporating retardation factor into the model, resulting in the improved fitting to the data. It indicates that the transport model, into which retardation, kinetic reversible sorption, and kinetic irreversible sorption are incorporated, is suitable at describing bacterial transport in saturated column experiments. It is expected that the selected transport model could be applied to properly analyze the bacterial transport in saturated porous media.

Adsorption of methylene blue from an aqueous dyeing solution by use of santa barbara amorphous-15 nanostructure: Kinetic and isotherm studies

  • Alizadeh, Reza;Zeidi, Amir
    • Advances in environmental research
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    • v.6 no.2
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    • pp.113-125
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    • 2017
  • Santa Barbara Amorphous-15(SBA-15) nanoparticles were utilized as the inexpensive and effective adsorbents to remove methylene blue dye from the aqueous solution.SBA-15 was created by Zhao et al method. Infrared spectroscopy, X-ray diffraction and scanning electron microscopy (SEM) were used for the evaluated physical properties of SBA-15. The results of diffraction X-ray indicated that was the crystalline structure for it. Also IR spectroscopy indicated was a silica the whole structure of the groups and SEM image verify the structure of relatively identical particles size of SBA-15. Factors affecting adsorption including the amounts of adsorbent, pH and contact time were investigated by a SBA-15 nanomaterial design. The extent of dye removal enhanced with increasing initial dye concentration and pH from 4 to 10. The higher percentage adsorption were obtained under optimum conditions of variables (sorbent dose of 200 mg/liter, initial MB concentration 10 mg/liter, initial pH of 10 and temperature of $25^{\circ}C$). Maximum adsorption happened after the 2 hour and the kinetic processes of the dyes adsorption were described by applying the pseudo-first-order and the pseudo-second-order and the relatively High correlation with the kinetic Ellovich models. It was found that the pseudo-second-order models kinetic equation described the data of dye adsorption with a good correlation (R2>0.999) which indicated chemisorption mechanism. Freundlich and Langmuir adsorption models were investigated in conditions of variables (adsorbent dose 0.01 gr/liter, MB concentration 10, 20, 30 mg/liter, pH of 4, 7, 10, contact time 90 min and temperature of $27^{\circ}C$). The adsorption data were represented by Langmuir isotherm model. These values are higher than the adsorption capacities of some other adsorbents that have recently been published in the literature.

Review of the Existing Relative Biological Effectiveness Models for Carbon Ion Beam Therapy

  • Kim, Yejin;Kim, Jinsung;Cho, Seungryong
    • Progress in Medical Physics
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    • v.31 no.1
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    • pp.1-7
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    • 2020
  • Hadron therapy, such as carbon and helium ions, is increasingly coming to the fore for the treatment of cancers. Such hadron therapy has several advantages over conventional radiotherapy using photons and electrons physically and clinically. These advantages are due to the different physical and biological characteristics of heavy ions including high linear energy transfer and Bragg peak, which lead to the reduced exit dose, lower normal tissue complication probability and the increased relative biological effectiveness (RBE). Despite the promising prospects on the carbon ion radiation therapy, it is in dispute with which bio-mathematical models to calculate the carbon ion RBE. The two most widely used models are local effect model and microdosimetric kinetic model, which are actively utilized in Europe and Japan respectively. Such selection on the RBE model is a crucial issue in that the dose prescription for planning differs according to the models. In this study, we aim to (i) introduce the concept of RBE, (ii) clarify the determinants of RBE, and (iii) compare the existing RBE models for carbon ion therapy.

A Prototyping Method for Kinect Facade Design: Focusing on the Role of BIM and the Interaction between Digital and Analog Models (프로토타이핑 기법에 의한 키네틱 외피의 설계: 디지털-아날로그 모델의 상호작용과 BIM의 역할을 중심으로)

  • Kim, Do-Young;Kim, Sung-Ah
    • Journal of KIBIM
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    • v.5 no.1
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    • pp.16-24
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    • 2015
  • The kinetic façade system is an interactive building envelope which is adaptive to environmental condition by transforming the behaviour of its components. The design process of kinetic façade system calls for a novel approach. It needs to support designers to adopt technologies from multidisciplinary fields such as physical computing and robotics. In this paper, prototyping method is introduced as a useful technique for implementing kinetic façade systems. In order to incorporate prototyping method into architectural design process, two aspects are investigated in digital design studio: (1) The interactions between digital and analogue environments (2) The role of traditional design tools. Furthermore, the role of BIM is investigated by analyzing two aspects.

Estimation of Kinetic Parameters of Nonenzymatic Browning Reaction Using Equivalent Time at Reference Temperarture with Linearly Increasing Temperature Profile (정속가열(定速加熱)조건에서 표준온도상당시간(相當時間)을 이용한 비효소적 갈색화 반응의 동력학 파라미터 추정(推定))

  • Cho, Hyung-Yong;Kwon, Yun-Joong;Kim, In-Kyu;Pyun, Yu-Ruamg
    • Korean Journal of Food Science and Technology
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    • v.25 no.2
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    • pp.178-184
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    • 1993
  • The procedure using equivalent time at reference temperature has been assessed for the estimation of kinetic parameters with experimental data. Kinetic studies of nonenzymatic browning reaction in model and food system were carried out with linearly increasing temperature method. These kinetic parameters, n, $k_{ref}$ and $E_a$ of the systems were evaluated from original data in one step by nonlinear least square regression. The one step procedure yielded efficiently accurate parameter estimation. Computer simulated data with the kinetic models were well consistent with experimental data (average correlation coefficient=0.96).

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Kinetics and Equilibrium Study on β-glucosidase under High Hydrostatic Pressure (고압에서 β-glucosidase 반응속도론 및 평형에 관한 연구)

  • Han, Jin Young;Lee, Seung Ju
    • Food Engineering Progress
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    • v.15 no.3
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    • pp.214-220
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    • 2011
  • $\beta$-Glucosidase enzyme reaction under high hydrostatic pressure was investigated in terms of physical chemistry. A model substrate (p-nitrophenyl-${\beta}$-D-glucopyranoside(pNPG)) was used, and the pressure effects on the enzymatic hydrolysis (pNPG${\rightarrow}$pNP) at 25 MPa, 50 MPa, 75 MPa, and 100 MPa were analyzed. Two parts of the reaction such as kinetic and equilibrium stages were considered for mathematical modelling, and their physicochemical parameters such as forward and inverse reaction constants, equilibrium constant, volume change by pressure, etc. were mathematically modeled. The product concentration increased with pressure, and the two stages of reaction were observed. Prediction models were derived to numerically compute the product concentrations according to reaction time over kinetic to equilibrium stages under high pressure condition. Conclusively, the $\beta$-Glucosidase enzyme reaction could be activated by pressurization within 100 MPa, and the developed models were very successful in their prediction.

Fabrication of Iron Oxide Nanotubes by Anodization for Phosphorus Adsorption in Water (양극산화 공정을 이용한 Iron Oxide Nanotubes의 제조 및 수중 인 흡착)

  • Lee, Won-Hee;Lim, Han-Su;Kim, Jong-Oh
    • Journal of Korean Society of Water and Wastewater
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    • v.30 no.6
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    • pp.691-698
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    • 2016
  • This study was carried out to investigate the characterization of iron oxide nanotubes (INTs) by anodization method and applied adsorption isotherms and kinetic models for phosphate adsorption. SEM analysis was conducted to examine the INTs surface formation. Further XRD and XPS analysis were performed to observe the crystal structure of INTs before and after phosphate adsorption. AFM analysis was conducted to determine of Fe foil surface before and after anodization. Phosphate stock solution for adsorption experiment was prepared by $KH_2PO_4$. The batch experiment was conducted using 20 ml phosphate stock solution and $40cm^3$ of INTs in 50 ml conical tube. Adsorption isotherms were applied Langmuir and Freundlich models for adsorption equilibrium test of INTs. Pseudo first order and pseudo second order models were applied for interpretation of adsorption rate by reaction time. The determination coefficient ($R^2$) values of Langmuir and Freundlich models were 0.9157 and 0.8876 respectively.

Equilibrium, kinetic and thermodynamic studies of the adsorption of acidic dye onto bagasse fly ash

  • Shouman, Mona A.;Fathy, Nady A.;El-Khouly, Sahar M.;Attia, Amina A.
    • Carbon letters
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    • v.12 no.3
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    • pp.143-151
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    • 2011
  • Bagasse fly ash (BFA) is one of the important wastes generated in the sugar industry; it has been studied as a prospective low-cost adsorbent in the removal of congo red (CR) from aqueous solutions. Chemical treatment with $H_2O_2$ was applied in order to modify the adsorbability of the raw BFA. Batch studies were performed to evaluate the influence of various experimental parameters such as dye solution pH, contact time, adsorbent dose, and temperature. Both the adsorbents were characterized by Fourier-transform infrared spectrometer, energy-dispersive X-ray spectrophotometer and nitrogen adsorption at 77 K. Equilibrium isotherms for the adsorption of CR were analyzed by Langmuir, Freundlich and Temkin models using non-linear regression technique. Intraparticle diffusion seems to control the CR removal process. The obtained experimental data can be well described by Langmuir and also followed second order kinetic models. The calculated thermodynamic parameters indicate the feasibility of the adsorption process for the studied adsorbents. The results indicate that BFA can be efficiently used for the treatment of waste water containing dyes.