• 제목/요약/키워드: Modification factor

검색결과 668건 처리시간 0.028초

단주교각 강박스교량의 거동계수 (Behavior Factor of a Steel Box Bridge with Single Column Piers)

  • 박준봉;김종수;국승규
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2002년도 춘계 학술발표회 논문집
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    • pp.228-235
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    • 2002
  • As the response spectrum method generally used in the earthquake resistant design is a linear method, the nonlinear behavior of a structure is to be reflected with a specific factor. Such factors are provided in the "Design Criteria for Roadwaybridges"as response modification factors and in the Eurocode 8, Part 2 as behavior factors. In this study a 5-span steel box bridge with single column piers is selected and the behavior factor is determined. The linear time history analyses are carried out with a simple linear model, where the nonlinear behavior of piers leading to the ductile failure mechanism is considered as predetermined characteristic curves.

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탄소성 단자유도 구조물에 대한 연성계수의 통계적 분석 (Statistical Study of Ductility Factors for Elastic Perfectly Plastic SDOF Systems)

  • 강철규;최병정
    • 한국지진공학회논문집
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    • 제7권2호
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    • pp.39-48
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    • 2003
  • 반응수정계수의 핵심구성요소인 연성계수에 대하여 통계적 분석을 수행하였다. 연성계수의 체계적인 산정을 위하여 총 1,860개의 지진기록을 수집하였다. 수집된 지진기록을 지반 전단파의 평균속도에 따라 4가지로 분류하고, 탄소성 이력거동을 가지는 단자유도 구조물에 대하여 비탄성 스펙트럼을 작성하였다. 작성된 비탄성 스펙트럼으로부터 연성계수를 구하고, 변위연성비, 토질조건, 규모 및 진앙거리가 연성계수에 미지는 영향을 분석하였다. 토질 조건별로 평균연성계수를 구하고, 산정된 연성계수의 산포도를 검토하기 위하여 변동계수를 산정하였다.

Demand response modification factor for the investigation of inelastic response of base isolated structures

  • Cheraghi, Rashid Eddin;Izadifarda, Ramezan Ali
    • Earthquakes and Structures
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    • 제5권1호
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    • pp.23-48
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    • 2013
  • In this study, the effect of flexibility of superstructures and nonlinear characteristics of LRB (Lead Rubber Bearing) isolator on inelastic response of base isolated structures is investigated. To demonstrate the intensity of damage in superstructures, demand response modification factor without the consideration of damping reduction factor, demand RI, is used and the N2 method is applied to compute this factor. To evaluate the influence of superstructure flexibility on inelastic response of base isolated structures, different steel intermediate moment resisting frames with different heights have been investigated. In lead rubber bearing, the rubber provides flexibility and the lead is the source of damping; variations of aforementioned characteristics are also investigated on inelastic response of superstructures. It is observed that an increase in height of superstructure leads to higher value of demand RI till 4-story frame but afterward this factor remains constant; in other words, an increase in height until 4-story frame causes more damage in the superstructure but after that superstructure's damage is equal to the 4-story frame's. The results demonstrate that the low value of second stiffness (rubber stiffness in LRBs) tends to show a significant decrease in demand RI. Increase in value of characteristic strength (yield strength of the lead in LRBs) leads to decrease in the demand RI.

여중·고생들의 교복변형행동에 따른 외모에 대한 태도와 신체만족 (Attitudes toward Appearance and Body Satisfaction according to Uniform Modification Behavior of Middle and High School Girls)

  • 박은희;조현주
    • 패션비즈니스
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    • 제19권4호
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    • pp.168-182
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    • 2015
  • The purpose of this study is to classify students' attitudes towards uniform modification and analyze their subjective experience regarding appearance, and body satisfaction. Questionnaires were administered to 369 middle and high school girls living in Deagu Metropolitan City. Frequency, factor analysis, reliability analysis, correlation analysis, ${\chi}^2$-test, and t-test are all used for data analysis. Our findings are as follows. Two hundred thirty students (62.3%) agreed to modify their school uniforms to express their personalities and follow fashion trends. Motives for uniform modification had to do with social life, physical attractiveness, and practicality. Attitudes toward appearance are found to be shaped by appearance internalization, active management of appearance, appearance needs, social recognition, and conformity. The motives for uniform modification reveal a significant correlation with attitudes toward appearance. Uniform modification satisfaction differed depending on sub-variables of attitude toward appearance(active management of appearance, personalized appearance needs, social recognition, and body satisfaction, such as satisfaction with height and BMI). There was a significant difference in expression of intention for future plastic surgery depending on body image.

Interference Suppression Using Principal Subspace Modification in Multichannel Wiener Filter and Its Application to Speech Recognition

  • Kim, Gi-Bak
    • ETRI Journal
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    • 제32권6호
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    • pp.921-931
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    • 2010
  • It has been shown that the principal subspace-based multichannel Wiener filter (MWF) provides better performance than the conventional MWF for suppressing interference in the case of a single target source. It can efficiently estimate the target speech component in the principal subspace which estimates the acoustic transfer function up to a scaling factor. However, as the input signal-to-interference ratio (SIR) becomes lower, larger errors are incurred in the estimation of the acoustic transfer function by the principal subspace method, degrading the performance in interference suppression. In order to alleviate this problem, a principal subspace modification method was proposed in previous work. The principal subspace modification reduces the estimation error of the acoustic transfer function vector at low SIRs. In this work, a frequency-band dependent interpolation technique is further employed for the principal subspace modification. The speech recognition test is also conducted using the Sphinx-4 system and demonstrates the practical usefulness of the proposed method as a front processing for the speech recognizer in a distant-talking and interferer-present environment.

Oxidative Modification of Neurofilament-L Induced by Endogenous Neurotoxin, Salsolinol

  • Kang, Jung-Hoon
    • Bulletin of the Korean Chemical Society
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    • 제32권9호
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    • pp.3421-3424
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    • 2011
  • The endogenous neurotoxin, 1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline (salsolinol), has been considered a potential causative factor for the pathogenesis of Parkinson's disease (PD). In this study, we examined oxidative modification of neurofilament-L (NF-L) induced by salsolinol. When disassembled NF-L was incubated with salsolinol, the aggregation of protein was increased with the concentration of sasolinol. The formation of carbonyl compound was obtained in salsolinol-mediated NF-L aggregates. This process was protected by free radical scavengers, such as N-acetyl-L-cysteine and glutathione. These results suggest that the aggregation of NF-L is mediated by salsolinol via the generation of free radicals. We also investigated the effects of copper ion on salsolinol-mediated NF-L modification. In the presence of copper ions, salsolinol enhanced the modification of NF-L. We suggest that salsolinol might be related to abnormal aggregation of NF-L which may be involved in the pathogenesis of neurodegenerative diseases and related disorders.

Automatic Contrast Enhancement by Transfer Function Modification

  • Bae, Tae Wuk;Ahn, Sang Ho;Altunbasak, Yucel
    • ETRI Journal
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    • 제39권1호
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    • pp.76-86
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    • 2017
  • In this study, we propose an automatic contrast enhancement method based on transfer function modification (TFM) by histogram equalization. Previous histogram-based global contrast enhancement techniques employ histogram modification, whereas we propose a direct TFM technique that considers the mean brightness of an image during contrast enhancement. The mean point shifting method using a transfer function is proposed to preserve the mean brightness of an image. In addition, the linearization of transfer function technique, which has a histogram flattening effect, is designed to reduce visual artifacts. An attenuation factor is automatically determined using the maximum value of the probability density function in an image to control its rate of contrast. A new quantitative measurement method called sparsity of a histogram is proposed to obtain a better objective comparison relative to previous global contrast enhancement methods. According to our experimental results, we demonstrated the performance of our proposed method based on generalized measures and the newly proposed measurement.

교량의 지진거동에 미치는 영향인자에 관한 연구 (A Study of influence factors on the bridge seismic behavior)

  • 최종만;국승규;김준범;정동원
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2005년도 학술발표회 논문집
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    • pp.372-379
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    • 2005
  • The earthquake resistant design concept allows the nonlinear behavior of structures under the design earthquake. Therefore the response spectrum method provided in most codes introduces the response modification factors to consider the nonlinear behavior in the design process. For bridges, the response modification factors are given according to the ductility as well as the redundancy of piers. In this study, among influence factors on the nonlinear seismic behavior, the randomness of artificial accelerograms simulated with different durations, the pier ductility represented by the inelastic behavior characteristic curve and the regularity represented by pier heights are selected. The influence of such factor on the seismic behavior is investigated by comparing response modification factors calculated with the nonlinear time step analysis.

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혼합 위상 정보를 이용한 TTS 합성음 생성 알고리즘 (Speech Synthesis Algorithm Using Mixed Phase Information for TTS Systems)

  • 권철홍;이민규
    • 음성과학
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    • 제8권4호
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    • pp.35-43
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    • 2001
  • New speech synthesis algorithms capable of flexible prosody (especially F0) modification are desired for a high quality TTS system. TD-PSOLA is the most popular synthesis algorithm. The algorithm shows very high quality when F0 modification is limited. However, the quality degradation due to pitch epoch detection error becomes severe as the F0 modification factor becomes large. On the other hand, the vocoder framework is very flexible in F0 manipulation. The synthesized speech quality from the vocoder is far from natural human speech and suffers from buzziness. To remedy the buzzy quality from the vocoder and make more natural synthetic speech, we propose a mixed phase vocoder.

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지방부 도로구간의 사고수정계수 개발에 관한 연구 (A Study for Accident Modification Factors for Rural Road Segments)

  • 오주택;황정원
    • 한국도로학회논문집
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    • 제15권6호
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    • pp.113-123
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    • 2013
  • PURPOSES : Although numerous researches have been studied to reveal accident causations for road intersections, there are still many research gaps for road segments. It is mainly because of difficulty of data and lack of analytical method. This study aims to study accident causations for rural road segments and develop accident modification factors for safety evaluation. The accident modification factors can be used to improve road safety. METHODS : Methods for developing AMF are diverse. This study developed AMFs using accident prediction models and selected explanatory variables from the accident models. In order to select final AMFs, three different methods were applied in the study. RESULTS : As a result of the study, many AMFs such as horizontal curves or vertical curves were developed and explained the meanings of the results. CONCLUSIONS : This study introduced meaningful methods for developing significant AMFs and also showed several AMFs. It is expected that traffic or road engineers will be able to use the AMFs to improve road segment safety.