• Title/Summary/Keyword: Degradation model

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Motion Image Restoration by Inverse Filtering (역 필터링을 이용한 이동물체 영상복원)

  • 김영우;유광렬;이대영
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.12 no.2
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    • pp.176-188
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    • 1987
  • This paper presents a method for Digital Image Motion Restoration by inverse filtering. In order to onstruct optimal Restoration filter, We exactly have to model the degradation process, and therefrom, derive the inverse filter which has inverse charateristics of the degradation model. An Image taken from object which moves fast, is o suffer blurring. it can be modeled by integration process mathematically and analyzed to convolve a rectangular window over an image. in this paper, We analyzed it in the frequency domain, and studied a method for motion restoration using inverse filter has a directional Sinc property.

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Storage lifetime estimation of detonator in Fuse MTSQ KM577A1 (기계식 시한 신관 KM577A1용 기폭관 저장수명 예측)

  • Chang, Il-Ho;Park, Byung-Chan;Hwang, Taek-Sung;Hong, Suk-Whan;Back, Seung-Jun;Son, Young-Kap
    • Journal of Korean Society for Quality Management
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    • v.38 no.4
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    • pp.504-511
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    • 2010
  • A fuze detonator comprising star shells is an important device so that its failure usually leads to failure of the shells. In this paper, accelerated degradation tests of RD1333 (lead azide) using temperature stress were performed, and then degradation data of explosive power for the detonator were analyzed to predict the storage lifetime of detonator. Degradation data analysis to estimate the storage lifetime is based on a distribution-based degradation process. Statistical distribution parameters of explosive power degradation measures at each time were estimated for each temperature level, and then reliability of the detonator for each accelerated temperature level was estimated using both time-varying distribution parameters and critical level of explosive power. Arrhenius model was applied to estimate storage lifetime of the detonator under the field temperature condition. Accelerated distribution-based degradation analysis to estimate storage lifetime is explained in detail, and estimation results are compared to field data of storage lifetime in this paper.

Degradation of p-nitrophenol by Gamma Irradiation

  • Lee, O Mi;Kim, Tae-Hun;Yu, Seungho;Jung, In-ha;Lee, Myunjoo
    • Journal of Radiation Industry
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    • v.5 no.4
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    • pp.353-357
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    • 2011
  • Degradation of p-nitrophenol has been carried out using only gamma irradiation or gamma irradiation with $H_2O_2$ or $Na_2S_2O_8$. Effects of different operating parameters such as initial concentration ($50mg\;l^{-1}$, $100mg\;l^{-1}$, $200mg\;l^{-1}$, $300mg\;l^{-1}$, $400mg\;l^{-1}$, $500mg\;l^{-1}$ and $600mg\;l^{-1}$) on the extent of degradation has been investigated. At 5 kGy, $50mg\;l^{-1}$ p-nitrophenol was completely degraded, and the radiolytic degradation of p-nitrophenol was described by the pseudo-first-order kinetic model. The combination of gamma irradiation with $H_2O_2$ or $Na_2S_2O_8$ leads to an enhanced effect, which remarkably increased the degradation efficiency of p-nitrophenol and TOC removal. However, at high $H_2O_2$ concentration, the efficacy of p-nitrophenol degradation is reduced because ${\cdot}OH$ radicals are scavenged by $H_2O_2$ and $Na_2S_2O_8$.

Inelastic analysis of RC beam-column subassemblages under various loading histories

  • You, Young-Chan;Yi, Waon-Ho;Lee, Li-Hyung
    • Structural Engineering and Mechanics
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    • v.7 no.1
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    • pp.69-80
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    • 1999
  • The purpose of this study is to propose an analytical model for the simulation of the hysteretic behavior of RC (reinforced concrete) beam-column subassemblages under various loading histories. The discrete line element with inelastic rotational springs is adopted to model the different locations of the plastic hinging zone. The hysteresis model can be adopted for a dynamic two-dimensional inelastic analysis of RC frame structures. From the analysis of test results it is found that the stiffness deterioration caused by inelastic loading can be simulated with a function of basic pinching coefficients, ductility ratio and yield strength ratio of members. A new strength degradation coefficient is proposed to simulate the inelastic behavior of members as a function of the transverse steel spacing and section aspect ratio. The energy dissipation capacities calculated using the proposed model show a good agreement with test results within errors of 27%.

A Numerical Analysis on the Shear and Hydraulic behavior of Single Rock Joint with Roughness (거칠기를 고려한 단일 절리의 전단, 수리적 거동에 대한 수치해석)

  • 이희석;이연규
    • Proceedings of the Korean Society for Rock Mechanics Conference
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    • 2000.09a
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    • pp.117-128
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    • 2000
  • The development of proper joint model, which can describe real phenomena exactly and still can be used easily, is one of the most important element for the analysis of the mechanical and hydraulic behavior of discontinuous rock mass. In this study, an elasto-plastic constitutive model of joint behavior considering asperity degradation was extended with the concept of first and second order asperities. The proposed model was implemented to numerical code with discrete finite joint element. The parametric study with the various asperity angles and degradation coefficients showed that the model can reproduce the shear behavior of typical rough joints well. Results of laboratory monotonic and cyclic shear tests were compared with those of numerical tests to validate the model. The hydraulic model considering the relations between gouge production and aperture was introduced to the mechanical model. In an attempt to examine the performance of the model, comparative numerical test was conducted. Permeability between joint surfaces increased rapidly at the first stage, but became nearly constant with increasing shear displacement due to gouge production and uniform variation of aperture distribution.

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Bio-degradation of Phenol in Wastewater by Enzyme-loaded Membrane Reactor: Numerical Approach

  • Barbieri, Giuseppe;Choi, Seung-Hak;Scura, Francesco;Mazzei, Rosalinda;Giorno, Lidietta;Drioli, Enrico;Kim, Jeong-Hoon
    • Membrane Journal
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    • v.19 no.1
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    • pp.72-82
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    • 2009
  • A mathematical model was written for simulating the removal of phenol from wastewater in enzyme-loaded membrane reactor (EMR). The numerical simulation program was developed so as to predict the degradation of phenol through an EMR. Numerical model proves to be effective in searching for optimal operating conditions and creating an optimal microenvironment for the biocatalyst in order to optimize productivity. In this study, several dimensionless parameters such as Thiele Modulus (${\phi}^2$, dimensionless Michaelis-Menten constant ($\xi$), Peclet number (Pe) were introduced to simplify their effects on system efficiency. In particular, the study of phenol conversion at different feed compositions shows that low phenol concentrations and high Thiele Modulus values lead to higher reactant degradation.

Analysis of Non-Linear Behavior in Silty Sand (실트질 모래지반의 비선형 거동특성 분석)

  • Lee, Kyung-Sook;Kim, Hyun-Ju;Lee, Jun-Hwan
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.1159-1166
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    • 2005
  • In the present study, a series of laboratory tests with sands of different silt contents, are conducted and methods to assess non-linear behaviors based on in-situ test results are proposed. Modified hyperbolic stress-strain model is used to analyze non-linearity of silty sands in terms of non-linear degradation parameters f and g as a function of silt contents and relative density $D_R$. Stress-strain relationship results were obtained from a series of triaxial tests on sands containing different amounts of silt. Initial shear modulus which was applied to normalize modulus degradation of silty sands were determined based on the resonant column test results. From the laboratory test results, it was observed that, as the relative density increases, values of f decrease and those of g increase. Cone resistance $q_c$ for silty soil condition used in the triaxial tests were estimated based on the cavity expansion analysis. A suggestion to make an estimation of degradation parameters f and g as a function of fine contents is addressed in terms of cone resistance $q_c$ .

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CO2 Emission, Energy Consumption and Economic Development: A Case of Bangladesh

  • Islam, Md. Zahidul;Ahmed, Zaima;Saifullah, Md. Khaled;Huda, Syed Nayeemul;Al-Islam, Shamil M.
    • The Journal of Asian Finance, Economics and Business
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    • v.4 no.4
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    • pp.61-66
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    • 2017
  • Environmental awareness and its relation to the development of economy has garnered increased attention in recent years. Researchers, over the years, have argued that sustainable development warrants for minimizing environmental degradation since one depends on the other. This study analyzes the relationship between environmental degradation (carbon emission taken as proxy for degradation), economic growth, total energy consumption and industrial production index growth in Bangladesh from year 1998 to 2013. This study uses Vector Autoregression (VAR) Model and variance decomposition of VAR to analyze the effect of these variables on carbon emission and vice-versa. The findings of VAR model suggest that industrial production and GDP per capita has significant relationship with carbon emission. Further analysis through variance decomposition shows carbon emission has consistent impact on industrial production over time, whereas, industrial production has high impact on emission in the short run which fades in the long run which is consistent with Environmental Kuznets Curve (EKC) hypothesis. Carbon emission rising along with GDP per capita and at the same time having low impact in the long run on industrial index indicates there may be other sources of pollution introduced with the rise in income of the economy over time.

Photomineralisation of Reactive Black 5 with ZnO using Solar and UV-A Light (태양광과 UV-A 빛 하에서 ZnO 을 이용한 Reactive Black 5의 광분해작용)

  • Amisha, S.;Selvam, K.;Sobana, N.;Swaminathan, M.
    • Journal of the Korean Chemical Society
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    • v.52 no.1
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    • pp.66-72
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    • 2008
  • The photocatalytic degradation of a textile diazo dye in aqueous solution has been investigated under Solar and UV-A light. The effect of various parameters such as concentration of dye, amount of catalyst and pH on the degradation of dye has been studied. Addition of hydrogen peroxide, ammonium persulphate and isopropanol strongly influences the degradation rate. Kinetic analysis of photodegradation reveals that the degradation follows approximately pseudo first order kinetics according to the Langmuir-Hinshelwood model. Carbon dioxide, nitrate and sulphate ions have been identified as mineralisation products. The photocatalyst ZnO was found to be more efficient in UV-A light than in Solar light.

Salinosporamides A and B Inhibit Proteasome Activity and Delay the Degradation of N-end Rule Model Substrates

  • Shin, Seung Kyun;Bang, Dae In;Choi, Won Hoon;Kim, Seong-Hwan;Oh, Dong-Chan;Lee, Min Jae
    • Bulletin of the Korean Chemical Society
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    • v.34 no.5
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    • pp.1425-1428
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    • 2013
  • The proteasome, which is highly evolutionarily conserved, is responsible for the degradation of most short-lived proteins in cells. Small-molecule inhibitors targeting the proteasome's degradative activity have been extensively developed as lead compounds for various human diseases. An exemplified molecule is bortezomib, which was approved by FDA in 2003 for the treatment of multiple myeloma. Here, using transiently and stably expressed N-end rule model substrates in mammalian cells, we evaluated and identified that salinosporamide A and salinosporamide B effectively inhibited the proteasomal degradation. Considering that a variety of proteasome substrates are implicated in the pathogenesis of many diseases, they have the potential to be clinically applicable as therapeutic agents.