• 제목/요약/키워드: Work Response

검색결과 2,090건 처리시간 0.038초

Using harmonic class loading for damage identification of plates by wavelet transformation approach

  • Beheshti-Aval, S.B.;Taherinasab, M.;Noori, M.
    • Smart Structures and Systems
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    • 제8권3호
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    • pp.253-274
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    • 2011
  • In this paper, the harmonic displacement response of a damaged square plate with all-over part-through damage parallel to one edge is utilized as the input signal function in wavelet analysis. The method requires the properties of the damaged plate, i.e., no information about the original undamaged structure is required. The location of damage is identified by sudden changes in the spatial variation of transformed response. The incurred damage causes a change in the stiffness or mass of the plate. This causes a localized singularity which can be identified by a wavelet analysis of the displacement response. In this study via numerical examples shown by using harmonic response is more versatile and effective compared with the static deflection response, specially in the presence of noise. In the light of the obtained results, suggestions for future work are presented and discussed.

중주파수 응답해석을 위한 축소 기법 (Model Order Reduction for Mid-Frequency Response Analysis)

  • 고진환
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2009년도 정기 학술대회
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    • pp.135-138
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    • 2009
  • Most of the studies use model order reduction for low frequency (LF) response analysis due to their high computational efficiency. In LF response analysis, one of model order reduction, algebraic substructuring (AS) retains all LF modes when using the modal superposition. However, in mid-frequency (MF) response analysis, the LF modes make very little contribution and also increase the number of retained modes, which leads to loss of computational efficiency. Therefore, MF response analysis should consider low truncated modes to improve the computational efficiency. The current work is focused on improving the computational efficiency using a AS and a frequency sweep algorithm. Finite element simulation for a MEMS resonator array showed that the performance of the presented method is superior to a conventional method.

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Positive and negative regulation of the Drosophila immune response

  • Aggarwal, Kamna;Silverman, Neal
    • BMB Reports
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    • 제41권4호
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    • pp.267-277
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    • 2008
  • Insects mount a robust innate immune response against a wide array of microbial pathogens. The hallmark of the Drosophila humoral immune response is the rapid production of anti-microbial peptides in the fat body and their release into the circulation. Two recognition and signaling cascades regulate expression of these antimicrobial peptide genes. The Toll pathway is activated by fungal and many Gram-positive bacterial infections, whereas the immune deficiency (IMD) pathway responds to Gram-negative bacteria. Recent work has shown that the intensity and duration of the Drosophila immune response is tightly regulated. As in mammals, hyperactivated immune responses are detrimental, and the proper down-modulation of immunity is critical for protective immunity and health. In order to keep the immune response properly modulated, the Toll and IMD pathways are controlled at multiple levels by a series of negative regulators. In this review, we focus on recent advances identifying and characterizing the negative regulators of these pathways.

Seismic response and retrofitting proposals of the St. Titus Chruch, Heraklion, Crete, Greece

  • Tzanakis, Michael J.;Papagiannopoulos, George A.;Hatzigeorgiou, George D.
    • Earthquakes and Structures
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    • 제10권6호
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    • pp.1347-1367
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    • 2016
  • The purpose of this work is to investigate the seismic behavior of St. Titus Church in Heraklion, Crete, Greece as well as the need of its seismic retrofitting. A numerical model of the Church is constructed using shell finite elements and it is then seismically examined using response spectrum and linear time-history analyses. Effects of soil-structure interaction have been also taken into account. The Church without retrofit is expected to exhibit extensive tensile failures and many compressive ones. Aiming to maintain the architectural character of the structure as well as to increase its seismic resistance, a retrofitting procedure involving injection of cement grout in conjunction with reinforced concrete jacketing to the internal side of the masonry walls is proposed. A numerical implementation of the proposed seismic retrofitting is performed and its effect is evaluated by response spectrum and linear time-history analyses. From the results of these analyses, it is shown that compressive failures are eliminated while only few tensile failures of local character take place.

The effects of work environment monitoring organization's analysts' equipment and chemical substance incident response to the safety management awareness

  • Park, Hyun-A;Choi, Seo-Yeon;Rie, Dong-Ho
    • 한국컴퓨터정보학회논문지
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    • 제22권5호
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    • pp.97-103
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    • 2017
  • In this paper, we propose a method to investigate the safety consciousness of a analyst incident response. This study conducted a statistical survey on 154 analysts who hired as expert in environment monitoring organizations in South Korea. The results of the analyses showed that respondents had good awareness on the equipment incident response and complied with laboratory safety regulations very well. Secondly, respondents were aware of the importance in the order of equipment incident response, an analytical laboratory incident response, and the cause of a chemical substance associated incident in an analytical laboratory in regarding the regulation compliance for creating a safe laboratory environment and the securement of laboratory safety. Therefore, (it was identified that) it would be necessary to create a safe environment and integrate a safety management system.

Multi-time probability density functions of the dynamic non-Gaussian response of structures

  • Falsone, Giovanni;Laudani, Rossella
    • Structural Engineering and Mechanics
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    • 제76권5호
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    • pp.631-641
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    • 2020
  • In the present work, an approach for the multiple time probabilistic characterization of the response of linear structural systems subjected to random non-Gaussian processes is presented. Its fundamental property is working directly on the multiple time probability density functions of the actions and of the response. This avoids of passing through the evaluation of the response statistical moments at multiple time or correlations, reducing the computational effort in a consistent measure. This approach is the extension to the multiple time case of a previously published dynamic Probability Transformation Method (PTM) working on a single evolution of the response statistics. The application to some simple examples has revealed the efficiency of the method, both in terms of computational effort and in terms of accuracy.

직장 내 성희롱과 관련변인 분석 (Sexual Harassment at Work and Related Variables)

  • 김경신;김정란
    • 한국가정과학회지
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    • 제2권2호
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    • pp.1-16
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    • 1999
  • The purposes of this research were to find the general trends of sexual harassment at work and to investigate the differences of related variables. The data were obtained through 321 employee living in Kwangju. The major findings were as follows : 1) 53.0% of respondents reported that they had experienced the offence of sexual harassment at work at least once. And 57.9% of respondents reported that they had experienced the victimization of sexual harassment at work at least once. 2) The most apparent response of victimization at work was ‘anger’. And the most frequent coping behavior was ‘smiling or joking’. 3) The offence style of sexual harassment was different by sex, men's marriage, and sex-role attitude. The victimization style of sexual harassment was different by sex, job, women rate in workplace, attitude toward sexual harassment, and sex-role attitude.

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중소 병원 간호사들의 업무상 손상경험에 영향을 미치는 요인파악 (Factors Associated with Work-Related Injuries of Nurses in Small and Medium Sized Hospitals)

  • 황지인;황은정
    • 간호행정학회지
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    • 제16권3호
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    • pp.306-313
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    • 2010
  • Purpose: This study was conducted to examine the factors associated with work related injuries of nurses in small and medium sized hospitals. Method: A cross-sectional survey was conducted with nurses in eight hospitals from October 2007 to January 2008. A questionnaire was designed to collect information on nurses' work related injuries, and individual and job related characteristics. The response rate was 65.1%. Data from 294 nurses were analyzed. Multiple logistic regression analysis was performed to determine factors associated with work related injuries. Result: Of the 294 nurses, 19.1% (n=56) responded as having at least one injury during their job performance. The logistic regression analysis revealed that the significant factors influencing work related injuries were job satisfaction, stress recognition, and hospital's location. Nurses with a higher job satisfaction were less likely to experience work related injuries (OR=0.58). Nurses with a higher stress recognition (OR=2.57) and those working at hospitals in metropolitan cities (OR=3.28) were more likely to experience work related injuries. Conclusions: The result of this study indicated that a substantial proportion of nurses in small and medium sized hospitals had experienced injuries related to nursing job. Interventions to prevent work related injuries among nurses should take into account the job satisfaction, stress recognition, and hospital characteristics.

2자유도 제어기를 이용한 CNC볼엔드밀링 공정에서 절삭력과 위치의 동시제어 (Simultaneous Control of Cutting Force and Position Using Two Degree-of- Freedom Controller in CNC Ball-end Milling Process)

  • 양호석;심영복;이건복
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2002년도 춘계학술대회 논문집
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    • pp.536-542
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    • 2002
  • There are two important variables in machining process control, which are feed and cutting speed. In this work, a two degree-of-freedom controller is designed and implemented to achieve on-line cutting force control and position control based on the modelling of cutting process dynamics which are established through step response test. Two schemes are proposed and implemented. The first is feed control under the constant spindle speed and spindle speed control under the constant feed speed. The second is a simultaneous control of feed and spindle speed. The last performs a position control under the constant cutting force. Those are confirmed to work properly. Especially the latter shows a faster response.

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CNC 볼엔드밀링 공정에서 2자유도 제어기를 이용한 절삭력 제어 (Cutting Force Control Using A Two Degree-of-Freedom Controller in Ball-end Milling Processes)

  • 양호석;심영복;이건복
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2002년도 춘계학술대회 논문집
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    • pp.219-224
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    • 2002
  • There are two important variables in machining process control, which are feed and cutting speed. In this work, a two degree-of-freedom controller is designed and implemented to achieve on-line cutting force control based on the modelling of cutting process dynamics which are established through step response test. Two schemes are proposed and implemented. The first is feed control under the constant spindle speed and spindle speed control under the constant fled speed. The second is a simultaneous control of feed and spindle speed. Those are confirmed to work properly. Especially the latter shows a faster response and we'll be evaluated to pare away workpiece by simultaneous control of position and cutting farce sooner or later.

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