• Title/Summary/Keyword: Arrhenius law

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Studies on the Drying Methods of Sea Foods 2. Fixed-Bed Drying of Cuttlefish (수산식품의 건조방법에 관한 연구 2. 갑오징어의 고정층건조)

  • HUR Jong-Wha
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.15 no.3
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    • pp.207-210
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    • 1982
  • For the removal of initial water content in cuttlefish, the effects of fixed-bed drying condition on the drying rate were investigated, with following results. 1. The drying rate of cuttlefish dried at fixed-bed condition was also faster than that at natural convection type or hot air dryer.2. By controlling air temperature and its direction to cut-and-peeled sample the drying time can be reduced to 2 hrs. 3. Shirai's equation and Arrhenius' law were applicable to fixed-bed dried cuttlefish. Drying rate constant (k) by Shirai's equation, and Arrhenius' plot were as shown in Table 3, 4 and Fig.3, respectively.

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An Accelerated Degradation Test of Nuclear Power Plants Communication Cable Jacket (원자력 발전소용 통신케이블 자켓의 가속열화시험)

  • Jung, Jae Han;Kim, Yong Soo
    • Journal of Korean Society for Quality Management
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    • v.45 no.4
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    • pp.969-980
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    • 2017
  • Purpose: The purpose of this study was to estimate the lifetime, and verify the target lifetime at steady state temperature, of communication cable jackets used in nuclear power plants. Method: This study was completed according to test and analysis methods required by international standards. After measuring the residual elongation(%) of specimens at specific points in time with the accelerated degradation test, average failure time of each temperature was computed. Thus, the activation energy could be derived by applying the temperature-Arrhenius law to estimate cable jacket lifetime at steady state temperature. Results: The cable jacket lifetime was estimated as 363.8 years assuming a normal nuclear power plant operating temperature of $90^{\circ}C$. Conclusion: To ascertain stable operating conditions for a nuclear power plant, accelerated degradation tests were performed according to the Arrhenius law for components of the nuclear power plants. The lifetime was estimated from the degradation data collected during the accelerated degradation test.

Oxidation Study on the Fabrication of Fe-36Ni Oxide Powder from Its Scrap

  • Yun, Jung Yeul;Park, Man Ho;Yang, Sangsun;Lee, Dong-Won;Wang, Jei-Pil
    • Journal of Powder Materials
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    • v.20 no.1
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    • pp.48-52
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    • 2013
  • A study of oxidation kinetic of Fe-36Ni alloy has been investigated using thermogravimetric apparatus (TGA) in an attempt to define the basic mechanism over a range of temperature of 400 to $1000^{\circ}C$ and finally to fabricate its powder. The oxidation rate was increased with increasing temperature and oxidation behavior of the alloy followed a parabolic rate law at elevated temperature. Temperature dependence of the reaction rate was determined with Arrhenius-type equation and activation energy was calculated to be 106.49 kJ/mol. Based on the kinetic data and micro-structure examination, oxidation mechanism was revealed that iron ions and electrons might migrate outward along grain boundaries and oxygen anion diffused inward through a spinel structure, $(Ni,Fe)_3O_4$.

Life-Time Prediction of HNBR Diaphragm in Oil Reservoir (유압구동장치 동력원용 고무 다이아프램 저유기의 수명 예측 연구)

  • Kim, Sol A
    • Journal of Drive and Control
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    • v.18 no.2
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    • pp.32-37
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    • 2021
  • The piston reservoir is mainly used in hydraulic blow-down system for aerospace engineering. The reservoir is heavy due to both hydraulic cylinder and piston in pressurization. The positive expulsion tank with rubber diaphragm has been mostly applied propellant and fuel tank at low pressure to satellites. To reduce weight, the reservoir that can be used at high pressure with rubber diaphragm was developed. In this research, the prediction of life-time for the rubber diaphragm was implemented through an accelerated life test, as a part of development of new reservoir. Also, the diaphragm was stored in an temperature chamber at the same condition as and operation with hydraulic oil. As a result, the life-time for a rubber diaphragm was successfully evaluated via Arrhenius law and Time-Temperature Superposition based on failure times over temperatures in the accelerated test.

Effect of Temperature Change on the Respiration Characteristics of Vegetables

  • Kawagoe, Yoshinori;Seo, Yasuhisa;Oshita, Sei-Ichi;Sagara, Yasuyuki
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1996.06c
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    • pp.947-952
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    • 1996
  • The effect of fluctuating temperature on the respiration of vegetables has been investigated. Spinach was selected as the experimental material because of its high respiratory activity and kept under the condition that temperature changed alternately at low and high levels every 4 hours. The low-high level temperature combination was set in $1-10^{\circ}C,{\;}1-20^{\circ}C{\;}and{\;}1-30^{\circ}C$. Respiration was evaluated in terms of quantity of $CO_2$ evolved from spinach. The evolution rate of $CO_2$ was determined by a change in its concentration. The evaluation rate of $CO_2$ followed closely the temperature change. In the temperature combinations at $1-10^{\circ}C{\;}and{\;}1-20^{\circ}C$, the relationship between $CO_2$ evolution rate and temperature was found to be able to express by Arrhenius law, while at $1-30^{\circ}C$, it did not obey the law.

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A Study on Reliability Test of Super-Capacitor for Electric Railway Regenerative Energy Storage System (전동차 회생에너지 저장 시스템용 슈퍼커패시터의 신뢰성시험에 관한 연구)

  • Lee, Sang-Min;Kim, Nam
    • 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.

A Basic Study on Fatigue Fracture Model at Elevated Temperatures by the Dimensional Analysis Method (차원해석법에 의한 고온피로 파괴 모델의 기초적 연구)

  • 서창민;김영호;권오헌
    • Journal of Ocean Engineering and Technology
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    • v.6 no.1
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    • pp.105-112
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    • 1992
  • The main purpose of this study is to derive a law of fatigue crack growth rate in the region of elastic or elasto-plastic fracture mechanics at elevated temperatures through the application of dimensional analysis. An equation of elasto-plastic fatigue crack growth rate at elevated temperatures appeared a new Arrhenius type equation containing J-integral range and absolute temperature. The elastic or elasto-plastic crack growth rate equation shows a fairly good agreement with the experimental results for Cr-Mo-V rotor steel and Hastelloy-X alloy in the comparatively wide temperature ranges.

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가속수명시험을 통한 신뢰성보험요율 추정 - 합금무계목인발강관의 사례를 중심으로 -

  • Hong, Yeon-Ung;Jeong, Yeong-Hun
    • 한국데이터정보과학회:학술대회논문집
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    • 2004.04a
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    • pp.1-5
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    • 2004
  • In this paper, we calculate the premium rate of reliability insurance policy for T11 composite metreial under the assumption of Weibull physics of failure and Arrhenius law. We also describe the performance factors which have an effect on failure characteristics of wiper motors. The maximum likelihood estimates of shape parameter and scale parameter are obtained by using interval censored real data of sample sizes 6 using MINITAB.

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TRAFFIC FLOW MODELS WITH NONLOCAL LOOKING AHEAD-BEHIND DYNAMICS

  • Lee, Yongki
    • Journal of the Korean Mathematical Society
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    • v.57 no.4
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    • pp.987-1004
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    • 2020
  • Motivated by the traffic flow model with Arrhenius looka-head relaxation dynamics introduced in [25], this paper proposes a traffic flow model with look ahead relaxation-behind intensification by inserting look behind intensification dynamics to the flux. Finite time shock formation conditions in the proposed model with various types of interaction potentials are identified. Several numerical experiments are performed in order to demonstrate the performance of the modified model. It is observed that, comparing to other well-known macroscopic traffic flow models, the model equipped with look ahead relaxation-behind intensification has both enhanced dispersive and smoothing effects.

Finite Element Analysis of Rubber Extrusion Forming Process (고무 압출성형 공정에 대한 유한요소 해석)

  • Ha, Yeon-Sik;Cho, Jin-Rae;Kim, Tae-Ho;Kim, Jun-Hyoung
    • Proceedings of the KSME Conference
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    • 2007.05a
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    • pp.762-767
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    • 2007
  • As a macromolecule material, melted rubber flow shows characteristics of shear thinning fluid. The dynamic viscosity of this rubber fluid is influenced by temperature and shear strain rate. In this study, the numerical simulation of rubber extrusion forming process has been performed using commercial CFD code, Polyflow. Power-law model considering the effect of shear rate is used for the computer simulation of this non-Newyonian flow. Also Non-isothermal behavior is considered as Arrhenius-law model. Distributions of velocity and temperature are predicted through the simulation.

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