• The Korean Journal of Applied Statistics
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• v.19 no.3
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• pp.555-564
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• 2006

Friedman rank-sum multiple comparison procedure is often applied to nonparametric multiple comparison method under randomized block design. Since this method does not use between-block information, we propose, in this paper, nonparametric multiple comparison procedures employing aligned method suggested by Hedges and Lehmann(1962) under randomized block design. The proposed procedure and Friedman procedure are compared by Monte Carlo simulation study.

• Applied Chemistry for Engineering
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• v.21 no.5
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• pp.505-508
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• 2010

The characteristics of desorption reaction for spent activated carbon produced from the manufacture of other chemical products in Shiwha/Banwal industrial complex were investigated. TGA (Thermogravimetric Analyzer) was used to study for characteristics of desorption and kinetics. Then Friedman method and Freeman-carroll method were used to find the activation energy and the order of reaction. Activation energy by Friedman method was 24.82~46.49 kJ/moL. And then activation energy and order of reaction by Freeman-carroll method were 8.77~32.26 kJ/moL and 0.11~1.69.

• Korean Chemical Engineering Research
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• v.48 no.6
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• pp.752-756
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• 2010

Desorption reaction characteristics of the used activated carbons collected from painting process in Shiwha/Banwal industrial complex were investigated. Thermogravimetric analyzer was used to investigate the desorption characteristics. Activation energies and reaction orders for desorption reaction characteristics of used activated carbons were estimated by employing Friedman method and Freeman-Carroll method. In the used activated carbons collected from painting process, it was found that the activation energies were 20.6~43.2 kJ/mol in Friedman method and 12.3~26.5 kJ/mol in Freeman-carroll method, and reaction orders were 0.1~1.7.

• Korean Chemical Engineering Research
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• v.50 no.3
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• pp.551-555
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• 2012

Desorption reaction characteristics of the commercial activated carbons which were used for the removal of industrial odorants were investigated. BET specific surface area was analyzed to investigate the chemicophysical property of activated carbon. Adsorptivity of activated carbon was estimated by iodine number. Thermogravimetric analyzer (TGA) was used to investigate the desorption characteristics. Activation energies and reaction orders for reaction characteristics according to adsorption and desorption of activated carbons were estimated by employing the Friedman method and Freeman-Carroll method. Adsorptivity of reprocessed activated carbons were significantly lower than that of fresh activated carbons. In this study, it was found that the activation energies were 15.9~23.4 kJ/mol in Friedman method and 22.7~33.8 kJ/mol in Freeman-Carroll method.

• Korean Chemical Engineering Research
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• v.47 no.6
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• pp.676-682
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• 2009

Devolatilization of the Refuse Derived Fuel(RDF) which is produced at WonJu in Korea was characterized in air atmosphere with variation of heating rate(10, 20 and $30^{\circ}C/min$) in TGA. The results of TG Analysis have shown that the pyrolysis and char combustion of the RDF occurred in the range of $350{\sim}700^{\circ}C$ depending on the heating rate. Activation energy of the RDF which was determined by using Friedman and Ozawa-Flynn-Wall method was in the range of 14.44~18.40 kcal/mol. Also, reaction order(n) and pre-exponential factors(A) were 1.219 and $3.02{\times}10^5$ by using Friedman method, respectively. In order to find out the devolatilization mechanism of the RDF, twelve solid-state mechanisms defined by Coats Redfern Method were tested. The results of the Coats Redfern Method have shown that chemical reaction is the effective mechanism by comparison with the value of the activation energy which was derived from the Friedman and Flynn-Wall-Ozawa method and correlation coefficient from twelve solid-state mechanisms of Coats Redfern Method. The solid state decomposition mechanism of the RDF was found to be a decelerated $F_1$ type, random nucleation with one nucleus on the individual particle.

• Journal of the Korean Institute of Gas
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• v.1 no.1
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• pp.120-126
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• 1997

The thermal decomposition of low density polyethylene(LDPE) and $25\%{\~}48\%$ chlorinated polyethylene(CPE) were studied using a dynamic thermogravimetry in the stream of nitrogen gas with 20ml/min. The mathematic method, differential (Friedman) and Integral (Ozawa) method were used to obtain value of activation energy of decomposition energy on the reaction. The activation energies evaluated by the above methods agree with each other very well. The maximum average activation energy calculated was 71.71kcal/mol. The thermal decomposition of LDPE and CPE were considered to be carried out by main chain scission and the thermogravimetric trace curve agree with the theoretical equation.

• Elastomers and Composites
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• v.34 no.2
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• pp.135-146
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• 1999

The thermal degradation kinetics of SBR and tire were studied using a conventional thermogravimetric analysis in the stream nitrogen at a heating rate of 5, 10, 15, $20^{\circ}C/min$, respectively. Thermogravimetric curves and their derivatives were analyzed using various analytical methods to determine the kinetic parameters. The degradation of the SBR and tire was found to be a complex process which has multi-stages. The Friedman method gave average activation energies for the SBR and tire of 247.53kJ/mol and 230.00kJ/mol, respectively. Mean-while, the Ozawa method Eave 254.80kJ/mol and 215.76kJ/mol. It would appear that either. Friedman's differential method or Ozawa's integral method provided satisfactory mathematical approaches to determine the kinetic parameters for the degradation of the SBR and tire. Approximately 86% and 55% of oil products were obtained at a final temperature of $700^{\circ}C$ and a heating rate of $20^{\circ}C/min$ for the SBR and tire respectively.

• 한국연소학회:학술대회논문집
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• 2015.12a
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• pp.219-222
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• 2015

The kinetic analysis of energetic materials using Differential Scanning Calorimetry (DSC) is proposed. Friedman Isoconversional method is applied to DSC experiment data and AKTS software is used for analysis. The frequency factor and activation energy are extracted as a function of product mass fraction. The extracted kinetic scheme does not assume multiple chemical steps to describe the response of energetic materials; instead, multiple set of Arrhenius factors are used in describing a single global step. The proposed kinetic scheme has considerable advantage over the standard method based on One-Dimenaionl Time to Explosion (ODTX). Reaction rate and product mass fraction simulation are conducted to validate extracted kinetic scheme. Also a slow cook-off simulation is implemented for validating the applicability of the extracted kinetics scheme to a practical thermal experiment.

• Journal of the Korean Society of Propulsion Engineers
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• v.19 no.1
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• pp.33-41
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• 2015

The kinetic analysis of energetic materials using Differential Scanning Calorimetry (DSC) is proposed. Friedman Isoconversional method is applied to DSC experiment data and AKTS software is used for analysis. The proposed kinetic scheme has considerable advantage over the standard method based on One-Dimenaionl Time to Explosion (ODTX). Reaction rate and product mass fraction simulation are conducted to validate extracted kinetic scheme. Also a slow cook-off simulation is implemented on $B/KNO_3$ for validating the applicability of the extracted kinetics scheme to a practical thermal experiment.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.547-553
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• 2017

Thermal analysis of three energetic materials used in pyroelectric device was performed using Differential Scanning Calorimetry (DSC). The theoretical method for extracting the reaction rate equation of energetic materials using DSC experimental data is proposed and the reaction rate extraction is performed. The results of the DSC were analyzed by the conversion method such as Friedman. Activation energy and frequency factor according to mass fraction were extracted to complete the reaction rate equation. The extracted reaction rate equation has a form that represents the entire chemical reaction process, not the assumption that the chemical reaction process of the high energy material is a main step in several stages. It has considerable advantages in terms of theoretical and accuracy as compared with the chemical reaction rate form extracted through conventional thermal analysis experiments. Using the derived reaction rate equation, we predicted the performance change of three energetic materials operating on actual storage condition over 20 years.