• 제목/요약/키워드: Feedback Relationship

검색결과 349건 처리시간 0.025초

Controlling the Depth of Microchannels Formed during Rolling-based Surface Texturing

  • Bui, Quang-Thanh;Ro, Seung-Kook;Park, Jong-Kweon
    • 한국생산제조학회지
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    • 제25권6호
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    • pp.410-420
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    • 2016
  • The geometric dimension and shape of microchannels that are formed during surface texturing are widely studied for applications in flow control, and drag and friction reduction. In this research, a new method for controlling the deformation of U channels during micro-rolling-based surface texturing was developed. Since the width of the U channels is almost constant, controlling the depth is essential. A calibration procedure of initial rolling gap, and proportional-integral PI controllers and a linear interpolation have been applied simultaneously to control the depth. The PI controllers drive the position of the pre-U grooved roll as well as the rolling gap. The relationship between the channel depth and rolling gap is linearized to create a feedback signal in the depth control system. The depth of micro channels is studied on A2021 aluminum lamina surfaces. Overall, the experimental results demonstrated the feasibility of the method for controlling the depth of microchannels.

MODELING OF HUMAN INDUCED CO2 EMISSION BY ASSIMILATING GIS AND SOC10-ECONIMICAL DATA TO SYSTEM DYNAMICS MODEL FOR OECD AND NON-OECD COUNTRIES

  • Goto, Shintaro
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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    • pp.3-8
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    • 1998
  • Using GIS and socio-economical data the relationship between human activities and global environmental change Is Analysed from the view point of food productivity and CO2 emission. Under the assumption that the population problem, the food problem and global warming due to energy consumption can be stabilized through managing land use, impacts of human activities such as consumption of food, energy and timber on global environment changes, and global population capacity are Analysed using developed system dynamics model in the research. In the model the world is divided into two groups: OECD countries and the others. Used global land use data set Is land cover map derived from satellite data, and potential distribution of arable land is estimated by the method of Clamor and Solomon which takes into consideration spatial distribution of climate data such as precipitation and evapotranspiration. In addition, impacts of CO2 emission from human activities on food production through global warming are included in the model as a feedback. The results of the analysis for BaU scenario and Toronto Conference scenario are similar to the results of existing models. From the result of this study, the human habitability in 2020 is 8 billion people, and CO2 emission in 2020 based on BaU Scenario and on Toronto Scenario is 1.7 and 1.2 times more than the 1986's respectively. Improving spatial resolution of the model by using global data to distribute the environmental variables and sauce-economical indices is left for further studies.

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환형 가스터빈 연소기에서 네트워크 모델을 이용한 연소불안정 해석 (Combustion Instability Analysis Using Network Model in an Annular Gas Turbine Combustor)

  • 표영민;윤명곤;김대식
    • 한국추진공학회지
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    • 제22권3호
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    • pp.72-80
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    • 2018
  • 연소불안정 현상은 연소기 내부에서 열발생 섭동과 음향 압력 섭동 사이의 피드백 관계로부터 도출된다. 특히 항공용 엔진에 대한 배출 가스 규제가 강화되면서, 환형 연소기에서의 연소불안정 연구에 대한 관심이 크게 증가하고 있다. 본 연구에서는 환형연소기에서 다양한 음향 모드를 계산할 수 있는 열음향 네트워크 모델을 개발 및 사용하였고, 이때 연소 모델은 화염전달함수를 적용하였다. 이와 같은 네트워크 모델을 사용하여 벤치마킹한 환형연소기의 실험데이터와 비교 분석하여 연소불안정 해석을 진행하였다.

참여의사결정과 대인신뢰가 생산성에 미치는 영향 (Participative Decision Making and Interpersonal Trust Effects on the Productivity)

  • 정기호;황종호;홍순복
    • 한국콘텐츠학회논문지
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    • 제5권6호
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    • pp.264-272
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    • 2005
  • 본 연구는 내부조직관계에서 대인신뢰를 구성원들의 상대방(부하, 동료, 상사)에 대한 능력, 상호 믿음과 지원에 기반을 두는 것으로 정의하고, 조직구성원들의 협력적 관계는 조직결과의 향상을 가져올 수 있다는 것을 가정하여, 참여적 의사결정이 조직생산성의 향상에도 영향을 미치는지를 확인하고자 한다. 연구 결과에 따르면 직무수행에 관련한 의사결정에 참여도와 성과의 피드백만족도 그리고 개방적 의사전달에 대한 만족도가 높을수록 업무생산성이 높아진다는 것을 알 수 있었다. 특히 대인신뢰에 기반을 둔 행정조직은 또 다른 관리적 도전인 문화적 다양성의 증대와 고객기대의 충족에 대처하게 되므로, 상사와 부하간의 대인신뢰를 구축하는 것은 구성원의 직무생산성을 증대시키고 조직몰입을 강화시킬 수 있는 원동력이 된다는 것을 알 수 있었다.

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Training-Effectiveness and Team-Performance in Public Organization

  • UMAR, Akmal;TAMSAH, Hasmin;MATTALATTA, M.;BAHARUDDIN, B.;LATIEF R, Abdul
    • The Journal of Asian Finance, Economics and Business
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    • 제7권11호
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    • pp.1021-1031
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    • 2020
  • This study aims to invest in empirical relationships in a model that becomes the process of Team-Performance due to participation in practical training through causality between Training Effectiveness variables, soft-skill competence, Employee-Creativity, and team performance. This study uses a quantitative approach. The analytical tool used is structural equation modeling (SEM) using AMOS version 23 software. Accidental sampling technique is used to collect the sample. As many as 202 respondents filled up a survey questionnaire with complete and valid answers. This study's results significantly contribute to fill the gap of inadequate empirical evidence that can answer critical questions about the missing link between training and employee-performance, more specifically between training-effectiveness and team-performance. The results showed that practical training would encourage employees' soft-skill competence, improve Employee-Creativity, and improve Team-Performance. Furthermore, training-effectiveness also plays a significant role in enhancing employee-creativity and helping in optimal team-performance. This study also found that the relationship between employee-creativity and team-performance did not show positive and significant results; therefore, empirically, it did not support the hypothesis built in this study. Practical training targeted towards increasing soft-skills and creativity is a fundamental reason which not only aims to contribute toward organizational performance but also provides personal feedback for self-development.

중년여성 자원봉사자의 자원봉사에 대한 평가와 성인 평생교육적 함의 (Middle-aged Female Volunteers' Evaluations on Their Volunteering and Implications for the Adult Life-long Education)

  • 김승희;김향은
    • 수산해양교육연구
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    • 제24권6호
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    • pp.1027-1041
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    • 2012
  • This study analyzed middle-aged woman volunteers' evaluations on their volunteering and its implications for the adult life-long education. The subjects were 126 women aged from 35 to 59 who enrolled in the volunteer centers in Busan, Korea. They participated in the survey of the volunteer effects and the factors that made them continue to volunteer. Survey said, middle-aged women volunteers perceived that they got positive feedback from others and themselves and it made them keep doing on volunteering. Based on their volunteering experiences, they reported the personal effects such as positivism, caring, volunteering capacity, industry, maturity and the family member's effects such as positivism and participating in their volunteering. They also mentioned that they had positive and negative effects on family relationship such as family relation reinforcement and being indifferent to their own family. Based on the research findings, it was the emphasized that supports for volunteering of the middle-aged women that helps them to accomplish the developmental tasks in the middle age are necessary. A scheme of linkage between volunteering and the adult life-long education was also dealt with. Finally, the implications on the further studies in the field were discussed.

LCL 필터를 사용하는 계통연계형 인버터의 동기좌표계 PI 전류제어 안정도 해석 (Analysis of Current Control Stability using PI Control in Synchronous Reference Frame for Grid-Connected Inverter with LCL Filter)

  • 조종민;이태진;윤동현;차한주
    • 전력전자학회논문지
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    • 제21권2호
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    • pp.168-174
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    • 2016
  • In this paper, current control using PI controller in the synchronous reference frame is analyzed through the relationship among bandwidth, resonance frequency, and sampling frequency in the grid-connected inverter with LCL filter. Stability is investigated by using bode plot in frequency domain and root locus in discrete domain. The feedback variable is the grid current, which is regulated by the PI controller in the synchronous reference frame. System delay is modeled as 1.5Ts, which contains computational and PWM modulator delay. Two resonance frequencies are given at 815 Hz and 3.16 kHz from LCL filter parameters. Sufficient phase and gain margins can be obtained to guarantee stable current control, in case that resonance frequency is above one-sixth of the sampling frequency. Unstable current control is performed when resonance frequency is below one-sixth of the sampling frequency. Analysis results of stability from frequency response and discrete response is the same regardless of resonance frequency. Finally, stability of current control based on theoretical analysis is clearly verified through simulation and experiment in grid-connected inverters with LCL filter.

상호작용 중심의 모-자 미술치료가 불안정 애착 아동 및 어머니의 상호작용에 미치는 영향 (The Effects of a Interaction Based Mother-Child Art Therapy on the Interaction of Child with Unstable Attachment and Mother)

  • 정창숙;박은미
    • 수산해양교육연구
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    • 제28권5호
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    • pp.1395-1406
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    • 2016
  • The purpose of this study was to examine the effects of interaction based mother-child art therapy on the change of child and mother's interactions in a child who was in trouble due to attachment problems. The subject in this study was a six-year-old child who faced difficulties in peer relationship building and who were maladjusted to kindergarten because of unstable attachment and negative feedback from his parents. Also, he showed serious problem behaviors at home. The ABA design was adopted among single-subject research designs, and the Target child was observed in the sessions in terms of the subfactors of Marschak's Behavioral Rating Scale to gather data related to the changes of child and mother's interactions. As a result of analyzing the collected data, there were positive changes in all the subfactors that were the child's verbal/nonverbal interactions, the mother's verbal/nonverbal interactions and mother-child interactions. Therefore the interaction based mother-child art therapy that was designed to boost child and mother's interactions was effective at furthering the mother-child interactions of the child with attachment problems.

On the Relationship between College Students' Attitude toward the Internet and their Self-directed English Learning Ability

  • Park, Kab-Yong;Sung, Tae-Soo;Joo, Chi-Woon
    • 한국컴퓨터정보학회논문지
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    • 제23권2호
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    • pp.117-123
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    • 2018
  • This article is to investigate the possibility that project-based classes introducing mobile phones can replace the monotony of traditional classes led by teachers as well as they can encourage students to take active part in the classes to some extent. The students in groups choose a genre for their own video projects (e.g., movie, drama, news, documentary, and commercial) and produce the video contents using a mobile phone for presentation made at the end of a semester. In the sense that the students are allowed to do video-based mobile phone projects, they can work independently outside of class, where time and space are more flexible and students are free from the anxiety of speaking or acting in front of an audience. A mobile phone project consists of around five stages done both in and outside of the classroom. All of these stages can be graded independently, including genre selection, drafting of scripts, peer review and revision, rehearsals, and presentation of the video. Feedback is given to students. After the presentation, students filled out a survey questionnaire sheet devised to analyze students' responses toward preferences and level of difficulty of the project activity. Finally, proposals are made for introduction of a better mobile phone-based project classes.

네트워크 모델을 이용한 환형 가스터빈 연소기에서의 연소불안정 해석 (Combustion Instability Analysis Using Network Model in an Annular Gas Turbine Combustor)

  • 표영민;윤명곤;김대식
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2017년도 제48회 춘계학술대회논문집
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    • pp.896-904
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    • 2017
  • 희박 예혼합 연소기는 NOx 배출 규제를 만족시키지만, 연소불안정 현상을 야기하는 단점을 갖고 있다. 이때 연소불안정 현상은 연소기 내부에서 열발생 섭동과 음향 압력 섭동 사이의 피드백 관계로부터 도출된다. 특히 항공용 엔진에 대한 배출 가스 규제가 강화되면서, 환형 연소기에서의 연소불안정 연구에 대한 관심이 크게 증가하고 있다. 본 연구에서는 환형연소기에서의 길이방향 및 환형 방향의 모드까지 계산할 수 있는 열음향 네트워크 모델을 개발 및 사용하였고, 이때 연소 모델은 화염전달함수를 적용하였다. 이와 같은 네트워크 모델을 사용하여 벤치마킹한 환형연소기의 실험데이터와 비교 분석하여 연소불안정 해석을 진행하였다.

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