• Title/Summary/Keyword: Equivalent Area

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Development of Wear Model concerning the Depth Behaviour

  • Kim, Hyung-Kyu;Lee, Young-Ho
    • KSTLE International Journal
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    • v.6 no.1
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    • pp.1-7
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    • 2005
  • Wear model for predicting the vehaviour of a depth is considered in this paper. It is deduced from the energy and volume based wear models such as the Archard equation and the workrate model. A new parameter of the equivalent depth ($D_e$= wear volume /worn area) is considered for the wear model of a depth prediction. A concenpt of a dissipated shear energy density is accommodated for in the suggested models. It is found that $D_e$ can distinguish the worn area shape. A cubic of $D_e$($D_e^3$) gives a better linear regression with the volume than that of the maximmum depth $D_{max}e$($D_{max}^3$) does. Both $D_{max}$ and $D_e$ are used for the presently suggested depth-based wear model. As a result, a wear depth profile can be simulated by a model using $D_{max}$. Wear resistance from the concern of an overall depth can be identified by the wear coefficient of the model using $D_e$.

New Approaches to Ultrasonic Classification and Sizing of Flaws in Weldments (초음파시험에 의한 용접결함의 종류판별과 크기산정의 새로운 기법)

  • 송성진
    • Journal of Welding and Joining
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    • v.13 no.4
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    • pp.132-146
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    • 1995
  • Flaw classification(determination of the flaw type) and flaw sizing (prediction of the flaw shape, orientation and sizing parameters) are very important issues in ultrasonic nondestructive evaluation of weldments. In this work, new techniques for both classification and sizing of flaws in weldments are described together with extensive review of previous works on both topics. In the area of flaw classification, a methodology is developed which can solve classification problems using probabilistic neural networks, and in the area of flaw sizing, a time-of-flight equivalent(TOFE) sizing method is presented.

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JSize: A Java Equivalent of the UNIX size program (JSize: 유닉스의 size에 대응하는 자바 등가 프로그램)

  • 양희재
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2003.10a
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    • pp.548-551
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    • 2003
  • JSize is a Java equivalent of the Unix size program. The Unix size program analyses an executable file and estimates the size of code and data segment when the file is loaded on memory. Likewise, JSize analyze a Java class file and estimates the size of class area when the file is loaded on memory. This paper presents the principles necessary to estimate the class area size with the information obtained from a class file. An experimental result is included to show the accuracy of estimation the JSize provides.

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Characteristics of film bulk acoustic resonators(FBAR) filters design with varying configuration of resonator (다양한 공진기 형태에 따른 압전박막필터 설계 및 특성)

  • Jong, Jung-Youn;Kim, Yong-Chun;Kwon, Sang-Jik;Kim, Kyung-Hwan;Yoon, Seok-Jin;Choi, Hyung-Wook
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2003.11a
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    • pp.275-278
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    • 2003
  • The aim of the study is to scrutinize the relationship between the area of resonance and center frequency with varying thickness by analyzing the characteristics of 2-port resonator. This was done through ideal design using Leach model equivalent model modified Mason model equivalent circuit for the application of bandpass filter high-frequency band with resonator Moreover, through the design of ladder-type BPF, we were able to observe changes in bandwidth, resonation, out-of-band rejection depending on the number and area of resonator.

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Comparison of the Equivalent Dose of the Lens Part and the Effective Dose of the Chest in the PET/CT Radiation Workers in the Nuclear Medicine Department (핵의학과 PET/CT실 방사선작업종사자의 수정체 부위의 등가선량과 흉부의 유효선량의 측정 비교)

  • Son, Sang-Joon;Park, Jeong-Kyu;Jung, Dong-Kyung;Park, Myeong-Hwan
    • Journal of radiological science and technology
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    • v.42 no.3
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    • pp.209-215
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    • 2019
  • Comparison of the effective dose of the chest and the equivalent dose of the lens site in the radiation workers working at four medical institutions with the PET / CT room located in one metropolitan city and province from April 1 to June 30, 2018 Respectively. Radioactive medicine were measured at the time of dispensing and at the time of injection. In this experiment, the average dispensing time per patient was 5.7 minutes and the average injection time was 3.1 minutes. The equivalent dose at the lens site was $0.78{\mu}Sv/h$ for 1 mCi, and the effective dose for chest was $0.18{\mu}Sv/h$ per 1 mCi. The equivalent dose at the lens site during injection was $0.88{\mu}Sv/h$ per mCi and the effective dose of chest was $0.20{\mu}Sv/h$ per mCi. The daily effective dose of the chest was $0.9{\pm}0.6{\mu}Sv$ and the equivalent dose of the lens site was $3.6{\pm}1.4{\mu}Sv$ during daily dosing for 20 days. The effective dose of the chest during the day was $0.6{\pm}0.5{\mu}Sv$ and the equivalent dose of the lens was $2.2{\pm}1.0{\mu}Sv$. At the time of dispensing, the equivalent dose of the lens was $0.187{\pm}0.035mSv$, the effective dose of the chest was $0.137{\pm}0.055mSv$, the equivalent dose of the lens was $0.247{\pm}0.057mSv$, and the effective dose of the monthly chest was $0.187{\pm}0.021mSv$. As a result of the corresponding sample test, the equivalent dose and the effective dose of the chest, the effective dose of the chest, the effective dose of the chest, the effective dose of the chest, The equivalent dose of the lens and the effective dose of the chest were statistically significant (p<0.05) with a significance of 0.000. However, there was no statistically significant difference (p>0.05) between the equivalent dose and the effective dose of the chest, the equivalent dose of the lens at the time of injection, and the effective dose of the chest at 0.138 and 0.230, respectively.

Examination of validation for equivalent gas to replace natural gas (천연가스를 모사하는 등가가스의 유효성 검토)

  • Kim, Jong-Min;Lee, Seungro;Lee, Chang-Eon
    • Journal of Energy Engineering
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    • v.22 no.2
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    • pp.128-135
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    • 2013
  • In order to estimate the combustion characteristics and the gas interchangeability for natural gas with various compositions per each production area, equivalent gas are using to replace natural gas. It is known that an equivalent gas has the same the heating value, the compression factor, the relative density, CO emission and the burning velocity as the original natural gas. However, it is not reported that the flame shape and thermal efficiency and NOx emission by real gas appliance. In this study, equivalent gas was examined the validation to replace natural gas. The CO emission the burning velocity and the flame temperature were reconfirmed, and the flame shape, the NOx emission and the thermal efficiency were numerically and experimentally investigated. As results, there was not a large difference between natural gas and equivalent gas. This result demonstrated that there was no problem using equivalent gas to replace natural gas.

A Study on the Synthesis of $Mn_3O_4$ and the Decomposition and Adsorption of $CO_2$ ($Mn_3O_4$의 합성과 $CO_2$ 분해 및 흡착에 관한 연구)

  • Kim Seung-Ho;Park Young-Goo;Ko Jae-Churl
    • Journal of the Korean Institute of Gas
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    • v.4 no.2 s.10
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    • pp.27-32
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    • 2000
  • In this study, $Mn_3O_4$ was synthesized by the different equivalent ratios using solution of $MnCL_2 {\cdot} 4H_2O$ and NaOH. We have investigated the crystal structure and surface area by XRD, BET Method, studied on the decompositon and adsorption of carbon dioxide with synthesized $Mn_3O_4$. As the results, we surveyed that main peak was $Mn_3O_4$, some Peaks were $MnO_2$ and $Mn_5O_8$ The specific surface area was ranged from $13.92m^2/g$ to $32.33m^2/g$. The decomposition of $CO_2$ was observed by the differential equivalent ratios at $450^{\circ}C$. $CO_2$ was well decomposed at equivalent ratio of 0.75. The amount of chemisorption of $CO_2$ was ranged from 2.885 to 19.628cc/g. Optimal equivalent ratio was 1.00 for the chemisorption of $CO_2$.

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Mapping of Liquefaction Potential in Songdo Reclamied Land (송도매립지역의 액상화 구역도 작성)

  • Kim, Sung-Hwan
    • Journal of the Society of Disaster Information
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    • v.14 no.3
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    • pp.296-304
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    • 2018
  • Purpose: This study was carried out to evaluate the liquefaction potential of the land reclamation area in Incheon by using the ProShake program for long frequency Hachinohe seismic wave and short frequency Ofunato seismic waves to interpret ground response. Method: The interpretation results and the Modified Seed and Idriss method were used to evaluate the liquefaction potential. The liquefaction potential index which proposed by Iwasaki was calculated to be used as a guide line to represent the liquefaction evaluation results at the given location. The equivalent liquefaction factor of safety presented by Kang(1999) was used as a quantitative index to draw up the mapping of liquefaction potential. Results: This paper presents the mapping of liquefaction potential for the Incheon seaside reclamation area using both the liquefaction potential index and the equivalent liquefaction factor of safety. Conclution: As a result, the mapping of liquefaction based on the liquefaction potential index and equivalent liquefaction factor of safety shows similar distribution pattern.

Flow Symmetry Breaking Effect According to Instability in Annular Combustor Part.I : Characteristics of Nozzle Arrangement (환형연소기에서 불안정성에 따른 유동적인 대칭성파괴 효과 Part I : 노즐 배치의 특성)

  • Huido Lee;Keeman Lee
    • Journal of the Korean Society of Propulsion Engineers
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    • v.26 no.6
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    • pp.62-73
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    • 2022
  • This research proposes a method to control combustion instability in a gas turbine combustor having an annular combustor form and compares the effect of flow symmetric braking through nozzle arrangement and the corresponding change in equivalent ratio. To this end, the symmetry breaking effect was confirmed through mode analysis of FFT, Time signal, and phase trajectory. In addition, the unstable area and the stable area were identified through mode analysis, and this was shown on the contour map. The present research shows that instability occurs when the equivalent ratio and the arrangement of the nozzles are symmetry or when the nozzles are continuously arranged, but if the arrangement and equivalent ratio are not symmetry, the combustion instability decreases dramatically even if the difference in the equivalent ratio is small.

Computation of equivalent material properties of woven fabric composites using homogenization technique (균질화기법을 이용한 WFC의 등가물성치 산출)

  • Jang, Ji-hyun;Yoon, Min-woo;Lee, Jin-hee
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.22 no.3
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    • pp.588-594
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    • 1998
  • Reliable three-dimensional models of woven fabric composites had scarcely been proposed for their geometric complexity. Simplified models, mostly one- or two-dimensional, currently used are not considered effective enough because of their oversimplifications. In this paper, the equivalent thermal conductivities and elasticity properties of woven fabric composites are computed using homogenization technique. The computational results show that the strength and thermal conductivity linearly increase with fiber volume fraction and that the variations of undulation of fibers has little effect on equivalent material properties. Homogenization technique is proved useful in the study of woven fabric composites and may find a lot more applications in the area.