• Journal of Applied Reliability
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• v.16 no.3
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• pp.238-244
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• 2016

Purpose: Domestic electric railway Regenerative Energy Storage System seriously affects the maintenance cost of the total operating expenses of nearly 60% of the total LCC (Life Cycle Cost) due to high dependence on foreign Leading company. Therefore by developing the system, it is important to lower the maintenance cost in the domestic supply. This study about the capacitor Reliability test and the purpose of this study is development electric railway Regenerative Energy Storage System. Methods: In case of, having a close relation between the temperature and the reaction rate, Accelerated Model was known that according to Arrhenius' law of chemical activity. If you apply this formula in using allowable temperature range of the capacitor can induce the Arrhenius empirical formula used in much Manufacture Fields. We evaluate the capacitors Leading company through the Arrhenius model. in order to providing a base for the localization of Ultra Capacitor. Conclusion: In this paper, we conducted a reliability test. And it was performed by the accelerated life test and Cycle Test with temperature and C-rate. and then MTBF and B10 life are estimated by analyzing the accelerated life test result. This is thought to need detailed study applying complex stress than about whether it matches the actual behavior in electric railway.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.5
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• pp.505-511
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• 2014

The EPDM(ethylene-propylene diene monomer) rubbers used for manufacturing engine radiator hoses can be degraded by locally generated electrical stress in addition to thermal and mechanical stresses. This study presents an accelerated life prediction of the EPDM rubber under electrochemical stresses using the Arrhenius formula under various aging temperatures($60^{\circ}C$, $80^{\circ}C$, and $100^{\circ}C$). The modified life prediction formula considers the relationship between the gradient($E_a/R$) and the Arrhenius constant(C). The effects of tensile strain(5%, 10%) on the life of these rubbers were investigated. The aging temperature influences EPDM rubber life, and tensile strain was predicted. It was confirmed that the modified life prediction was within the data deviation level of the test.

• Textile Coloration and Finishing
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• v.29 no.3
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• pp.155-161
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• 2017

In CPB(Cold-Pad-Batch) dyeing, the rubber of the padder roll is influenced by the heat, chemical and mechanical influences and thus aging of the padder roll rubber occurs. This study presents an accelerated thermal aging test of the CPB padder roll rubber with strong alkali conditions. Using Arrhenius formula of the various property values for the various aging temperatures($80^{\circ}C$, $90^{\circ}C$, $100^{\circ}C$) of the padder roll, the accelerated life predictions could be calculated. The threshold value of the property was set at different values. The hardness was set at the point where 5% degradation occurs based on the actual use conditions, and the tensile strength was set at the point where 50% degradation occurs based on the general life prediction standards. From the results of the different physical properties at differing temperatures, the Arrhenius plot could be obtained. Through the usage of the Arrhenius Equation, significant duration expectation could be predicted, and the chemical aging behavior of the CPB padder roll could be found at the arbitrary and actual temperatures.

• Bulletin of the Korean Chemical Society
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• v.7 no.1
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• pp.29-35
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• 1986

An empirical formula for semiconductive metal oxides is proposed relating nonstoichiometric value x to a temperature or an oxygen partial pressure such that experimental data can be represented more accurately by the formula than by the well-known Arrhenius-type equation. The proposed empirical formula is log x = A + $B{\cdot}1000/T\;+\;C{\cdot}$exp$(-D{\cdot}1000/T)$ for a temperature dependence and $log\;{\times}\;=a\;+b{\cdot}log\;Po_2\;+\;c{\cdot}$exp$(-d{\cdot}log\;Po_2)$ for an oxygen partial pressure dependence. The A, B, C, D and a, b, c, d are parameters which are evaluated by means of a best-fitting method to experimental data. Subsequently, this empirical formula has been applied to the n-type metal oxides of $Zn_{1+x}O,\; Cd_{1+x}O,\;and\;PrO_{1.8003-x}$, and the p-type metal oxides of $CoO_{1+x},\; FeO_{1+x},\;and\;Cu_2O_{1+x}$. It gives a very good agreement with the experimental data through the best-fitted parameters within 6% of relative error. It is also possible to explain approximately qualitative characters of the parameters A, B, C, D and a, b, c, d from theoretical bases.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.24 no.1
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• pp.13-16
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• 2018

Powdered infant formula is susceptible to oxidation in the presence of oxygen. Even though the product is usually packaged in nitrogen atmosphere, the oxygen ingress through the package layer may occur in case of flexible pouches and affects the oxidation of the product. $O_2$ barrier of the package is thus important variable to protect the product from oxidative deterioration. $O_2$ barrier property was investigated for aluminum-laminated small pillow packs of $3.5{\times}17.5cm$. Storage temperature and combination of primary and secondary packages were evaluated as variables affecting the barrier for conditions of empty pouch flushed with nitrogen. Apparent oxygen transmission rate of the primary package exposed to air was $2.32{\times}10^{-3}mL\;(STP)\;atm^{-1}\;d^{-1}$ at $30^{\circ}C$ and its temperature dependence could be explained by activation energy of $28.5kJ\;mol^{-1}$ in Arrhenius relationship. The additional secondary package of nylon/PE film containing 20 primary packages was ineffective in modulating package $O_2$ transmission and was only marginally helpful when combined with oxygen scavenger. The same was true in suppressing the product oxidation when the primary package was filled with 14 g of the formula.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.739-742
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• 2000

Nanostructured ZnS thin films were grown on the slide glass substrate by the chemical bath deposition using an aqueous so1ution Of ZnSO$_4$and CH$_3$CSNH$_2$at 95$^{\circ}C$. The average grain sizes of the ZnS thin film estimating from the Debye-Scherrer formula are 4.8 nm. The optical transmittance edge of the ZnS thin films (4.0 eV) was shifted to the shelter wavelength compared with that of the bulk ZnS (3.67 eV) due to the quantum size effects. The ZnS thin films showed a strong photoluminescence intensity and a sharp emission band from 410 to 480 nm 3t room temperature. The PWHM of photoluminescence peak was about 40 nm. For the viloet(410 nm) and blue(480 nm) emission of the ZnS thin films, the temperature dependence can be described by an Arrhenius equation with an activation energy of 168 and 157 meV, respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.332-339
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• 2020

This study was a prior study to establish the shelf life of bulletproof helmets, considered the aging factor of bulletproof helmets. To estimate the aging factor of bulletproof helmets, we established a hypothesis that the 'temperature' factor would have the greatest impact on the shelf life of the bulletproof helmet, considering the environmental treatment of the American army's bulletproof helmet's materials. To verify the hypothesis, high temperature acceleration environmental treatment of bulletproof helmets was performed, and the Arrhenius formula was applied to calculate the shelf life. The study result confirmed the negative correlation between bulletproof performance and high temperature, and the influence of temperature as an aging factor was not significant by deriving life by using the Arrhenius model. The limitation of this study is that we couldn't obtain enough samples due to the specificity (miliary supplies) of the test subjects. However, given that the life-related research on bulletproof helmets has not been carried out, this research has great implications and could be used as a reference for improving the Korean Army's bulletproof helmet specifications.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.4
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• pp.70-83
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• 1997

We made a selection of engine operating conditions in the natural aspiration type diesel engine as load and speed. The effects on the power, smoke emission and cylinder pressure characteristics of these variations in operating conditions were observed experimentally. Also, the smoke emission was predicted by using the Arrhenius equation and empirical equation of the smoke emission was made. At the same time, the correlations, between the combustion and smoke emission characteristic were examined. From the above results, it is clear that to prevent power dropping and to decrease exhaust fume whin the conditions are changed, one should improve the intake system. To do this, the best way is to lower the air-fuel mixing ratio. We found that the parameters of the indicated mean effective pressure, maximum pressure and its location and combustion duration, etc. change the motion in accordance with the conditions described above. Also, we found that the variation of the pressure cycle comes from an amplified variation of the early part of process. From the analysis of comparing combustion and exhaust fume, the exhaust fume is produced at the latter time of combustion and decreased when the combustion ratio is higher. Also, we developed a special formula which can predict the exhaust fume value according to the engine load and speed.

• Elastomers and Composites
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• v.31 no.1
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• pp.33-42
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• 1996

NR, NBR, and CR rubber were prepared by mixing filler in various ratios. Their vulcanization characteristics and thermal properties were studied. Vulcanization characteristics were investigated using cure curve that had been obtained from oscillating disk rheometer study. The Arrhenius law is known to describe the relationship between cure time and temperature of most elastomers. Curing could be done by the addition of sulfur, peroxides, and proper acceleratores. The optimum cure time that affects desirable values of modulus and tensile strength of the vulcanizate is taken as t90 as measured by a rheometer. Rubbers were cured in the rheometer at temperatures ranging from $130^{\circ}C\;to\;180^{\circ}C$ in order to check the validity of the curing system used. A linear relationship between ln(ts2) and ln(t90) was found for all elastomers. The term sensitivity has been used to describe the relationship between a change of ts2 to the corresponding change of t90 due to an increment of temperature. This is related to the formula of the compound.

• Journal of the Korean Society of Tobacco Science
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• v.18 no.2
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• pp.150-159
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• 1996

In this study, to obtain the basic data for the optimum moisture control system, moisture adsorption characteristics, adsorption isotherms models for water and surface physical characteristics of burley and flue-cured tobacco were investigated. By the hypothesis' the phenomenon of moisture adsorption of tobacco is the same as the first order reaction, the wetting constant (k) and equilibrium moisture content were obtained. And activation energy, frequency factors were also calculated by applying its data to Arrhenius equation. The Kamei's empirical formula of moisture adsorption isotherms showed the best agreement with the experimental data and its correlation coefficient (r) was 0.997. It can be seen that specific surface area of burley is 157 m2/g, that of flue-cured is 152 m2/g, -△H1 of adsorbed monolayer is 45,972 J/mol, 45,486 J/mol, respectively, and the condensation heat (40,595 J/mol) being caught in adsorbed multilayer is less than that of monolayer.