• 제목/요약/키워드: usage duration

검색결과 179건 처리시간 0.026초

불확실한 로보트 시스템의 제어와 파라미터 추정을 위한 반복학습제어기법 (Control and Parameter Estimation of Uncertain Robotic Systems by An Iterative Learning Method)

  • 국태용;이진수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1990년도 추계학술대회 논문집 학회본부
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    • pp.421-424
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    • 1990
  • An iterative learning control scheme for exact-tracking control and parameter estimation of uncertain robotic systems is presented. In the learning control structure, tracking and feedforward input converge globally and asymptotically as iteration increases. Since convergence of parameter errors depends only on the persistent exciting condition of system trajectories along the iteration independently of length of trajectories, it may be achieved with only system trajectories of small duration. In addition, these learning control schemes are expected to be effectively applicable to time-varying parametric systems as well as time-invariant systems, for the parameter estimation is performed at each fixed time along the iteration. Finally, no usage of acceleration signal and no in version of estimated inertia matrix in the parameter estimator makes these learning control schemes more feasible.

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육상수조 어류양식 생존율에 따른 비용분석모형 (Cost Analysis Model according to Mortality in Land-based Aquaculture)

  • 어윤양
    • 수산경영론집
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    • 제47권4호
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    • pp.1-13
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    • 2016
  • Fish mortality is the most important success factor in aquaculture management. To analyze the effect of mortality considering biological and economic condition is a important problem in land-based aquaculture. This study is aimed to analyze the effect of mortality for duration of cultivation in land-based aquaculture. This study builds the mathematical model that finds the value of decision variable to minimize cost that sums up the water pool usage cost, sorting cost, fingerling cost and feeding cost under critical standing corp constraint. The proposed mathematical model involves many aspects, both biological and economical: (1) number of fingerlings (2) timing and number of batch splitting event, based on (3) fish growth rate, (4) mortality, and (5) several farming expense. Numerical simulation model presented here in. The objective of numerical simulation is to provide for decision makers to analyse and comprehend the proposed model. When extensive biological and cost data become available, the proposed model can be widely applied to yield more accurate results.

모바일 그리드에서 데이터마이닝을 이용한 효율적인 사용자 패턴 연구 (Study of the effective use pattern using Data Mining in a mobile grid)

  • 김휴찬;김미정
    • 디지털산업정보학회논문지
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    • 제9권2호
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    • pp.23-32
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    • 2013
  • The purpose of this study is to make effective mobile grid considered general environment, which can be summarized as irregular mobility, service exploration, data sharing, variety of machines, limit to the battery duration, etc. The data was extracted from the Dartmouth College. We analysed mobile use pattern of a specific group and applied pattern using hybrid method. As a result, we could adjust infra usage effectively and appropriately and cost cutting and increase satisfaction of user. In this study, by applying weighting method based on access time interval, we analysed use pattern added time variation with association rule during users in mobile grid environment. We proposed more stable way to manage patterns in a mobile grid environment that is being used as a hybrid form to process the data value received from the server in real time. Further studies are needed to get appropriate use pattern by group using use patterns of various groups.

장기 코로나 처리에 따른 RTV 실리콘 절연재료의 특성변화 (Effect of Long-term Corona-discharge on RTV Silicone Rubber)

  • 연복희;안종식;허창수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집 Vol.14 No.1
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    • pp.266-269
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    • 2001
  • This paper investigated the aging characteristic under long-term corona discharge on roan temperature vulcanized silicone rubber, which has been using as a protective coating material for solving the contaminant problem. The applied electrical field is 10kV/cm ac and corona discharge treatment was applied on RTV silicone rubber sheet for maximum 250 hours. With the duration of corona discharge. the diffusible low molecular weight species increased, which was determined the usage of n-hexane extraction method. In addition, the contaminant layer was formed on the treated surface, and then measured the contact angle. We investigated the relation of contact angle and diffusible low molecular weight species. It is found that scissor of main chain PDMS and side chains $(CH_3)$ and the generation of LMW species were occurred by a corona discharge. The improvement of hydrophobicity rate is thought due to the increase of diffusible LMW species.

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복수 신용카드 중 실제 이용카드의 결정요인에 관한 연구 -복수와 단일 신용카드 소지자의 사용행태에 관한 비교분석- (Determinants in the Stage of Purchase Decision Making for Credit Cards)

  • 김동균
    • 경영과정보연구
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    • 제3권
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    • pp.439-460
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    • 1999
  • The purpose of this paper is to compare the characteristics between group that has only one credit card and group that has multiple credit cards in each stage of purchase decision making based on the literature in consumer behavior. Results indicated that (1) The number of credit cards that consumers has was affected by internal factor and reference factor, (2) depending on the number of credit cards, usage frequency, amount, and duration were differently showed and (3) inertia, point accumulation, and convenience were founded as determinants of using credit cards. Finally, theoretical and managerial implications of these findings are discussed.

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장기 코로나 처리에 따른 RTV 실리콘 절연재료의 특성변화 (Effect of Long-term Corona-discharge on RTV Silicone Rubber)

  • 연복희;안종식;허창수
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2001년도 추계학술대회 논문집
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    • pp.266-269
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    • 2001
  • This paper investigated the aging characteristic under long-term corona discharge on loon temperature vulcanized silicone rubber, which has been using as a protective coating material for solving the contaminant problem. The applied electrical field is 10kV/cm ac and corona discharge treatment was applied on RTV silicone rubber sheet for maximum 250 hours. With the duration of corona discharge, the diffusible low molecular weight species increased, which was determined the usage of n-hexane extraction method. In addition, the contaminant layer was formed on the treated surface, and then measured the contact angle. We investigated the relation of contact angle and diffusible low molecular weight species. It is found that scissor of main chain PDMS and side chains (CH$_3$) and the generation of LMW species were occurred by a corona discharge. The improvement of hydrophobicity rate is thought due to the increase of diffusible LMW species.

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Link Stability aware Reinforcement Learning based Network Path Planning

  • Quach, Hong-Nam;Jo, Hyeonjun;Yeom, Sungwoong;Kim, Kyungbaek
    • 스마트미디어저널
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    • 제11권5호
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    • pp.82-90
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    • 2022
  • Along with the growing popularity of 5G technology, providing flexible and personalized network services suitable for requirements of customers has also become a lucrative venture and business key for network service providers. Therefore, dynamic network provisioning is needed to help network service providers. Moreover, increasing user demand for network services meets specific requirements of users, including location, usage duration, and QoS. In this paper, a routing algorithm, which makes routing decisions using Reinforcement Learning (RL) based on the information about link stability, is proposed and called Link Stability aware Reinforcement Learning (LSRL) routing. To evaluate this algorithm, several mininet-based experiments with various network settings were conducted. As a result, it was observed that the proposed method accepts more requests through the evaluation than the past link annotated shorted path algorithm and it was demonstrated that the proposed approach is an appealing solution for dynamic network provisioning routing.

A Future Contraction Effect in Intertemporal Choice for Durable Goods

  • Kim, Byung Kyu
    • Asia Marketing Journal
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    • 제20권2호
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    • pp.29-40
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    • 2018
  • Recent research reported that perception of future time is non-linearly scaled. That is, as objective time gets longer, subjective perception of the objective time does not grow proportionally. The non-linear time perception implies that the same future time feels shorter when it starts in the future than when it starts immediately. The authors call this as a future contraction effect. The current research tests two important implications of the effect regarding consumers' intertemporal preference for durable goods. First, consumers who contract future more will be more impatient for durable goods compared to those who contract less because the former would feel to use the same durable goods longer when it is purchased immediately. Second, consumers' impatience will be alleviated when their tendency to contract future is reduced. The authors find support for these predictions through two studies. Taken together, the current research demonstrates a property of time perception that has important ramifications for understanding consumers' intertemporal preference for durable goods.

대학병원에서의 Teicoplanin의 사용 현황 조사 및 실태 평가 (The Evaluation of Teicoplanin Usage in a University Hospital)

  • 김은아;오정미
    • 한국임상약학회지
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    • 제11권1호
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    • pp.19-29
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    • 2001
  • Teicoplanin, a glycopeptide antibiotic, has potential for use as an alternative to vancomycin in the treatment of gram-positive bacterial infections. However, unlike vancomycin, there is a lack of study on teicoplanin's efficacy and safety and the guideline for its use is not available, yet. The objective of this study was to investigate and evaluate the pattern of teicoplanin usage in a university hospital. A retrospective study was performed on 72 adult patients, who took teicoplanin for 3 continuous days at D. University hospital from 1 January 1999 to 30 June 2000. The microorganisms treated with teicoplanin were methicillin-resistant Staphylocorcus aureus $(69\%)$, coagulase-negative Staphylococci $(12\%)$, Enterococcus $(4\%)$, vancomycin-resistant Enterococci $(2\%)$, Streptococci $(2\%)$, and Bacillus $(1\%)$. The types of infection treated with teicoplanin were surgical wound infection $(58\%)$, lower respiratory infection $(11\%)$, bactremia $(7\%)$, urinary tract infection $(5\%)$, pleural fluid infection $(4\%)$, and peritoneal fluid infection $(2\%)$. The mean duration of teicoplanin usage was 16.5 days and teicoplanin was used with 1.4 other antibiotics, which were aminoglycosides (isepamicin, amikacin, netilmicin, astromicin) or quinolones (ciprofloxacin, tosufloxacin) or the third generation cephalosporin (ceftazidime). Only 24 cases $(28.6\%)$ met with the criteria for the justification of use, and the rest of 60 cases $(71.4\%)$ did not meet the criteria. In 84 cases $(100\%)$, blood culture tests were performed prior to the initial dose of teicoplanin. In 83 cases $(99\%)$, serum creatinine were conducted before the initial doses. In 45 cases $(53.6\%)$, serum creatinine was monitored at least twice weekly. In 55 cases $(65.5\%)$, WBC was tested at least twice weekly. In 84 cases $(100\%)$, body temperature was monitored at least once per nursing shift. In 15 cases out of 56 cases, maximum temperature decreased at least 1 degree within 3 days of teicoplanin use. In 15 case out of 35 cases, WBC values were within the normal range after treatment. In 23 cases $(27.4\%)$, dosage regimen was appropriate. Drug-related adverse effects were reported in 13 cases. Nephrotoxicity (progressively increasing SCr. or sustained SCr increase of $\geq$0.5 mg/dl from baseline) was noted in five cases. Neutropenia (absolute neutrophil count <1,500 $cells/mm^3$) was noted in one case and eosinophilia (total eosinophil count >350 $cells/mm^3$) was noted in seven cases. A more strict control on use of teicoplanin is required, considering that teicoplanin is categorized as one of restricted antibiotics.

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공동주택의 급탕부하 지속시간 및 부하 패턴에 관한 실증연구 (An Empirical Study of Hot Water Supply Patterns and Peak Time in Apartment Housing with District Heating System)

  • 김성민;정광섭;김영일
    • 에너지공학
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    • 제21권4호
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    • pp.435-443
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    • 2012
  • 세계는 원유재고 감소와 국제 정세의 불안정으로 인해 지속적으로 상승하고 있는 유가와 화석연료 사용으로 인한 환경오염에 관심이 고조되고 있다. 국내의 경우 원유를 100% 수입하고 있으며, 사용되고 있는 에너지의 에너지원 중 97%를 수입에 의존하고 있기 때문에 유가 상승에 따른 영향은 더욱 민감하게 나타난다. 국내에 수입되고 유통되는 에너지의 97% 중 1/3 이상이 사무소나 주거용 난방, 급탕 및 취사용으로 사용되고 있다. 이에 따라 정부는 물론 산업체, 연구소 등에서 사무소 및 주거용 에너지 소비패턴으로 인한 경제적인 부담을 줄이고, 고효율 저에너지 기술개발을 통해 소비에너지를 절약함과 동시에 탄소배출을 억제하는 신기술에 대한 연구가 활발하게 이루어지고 있다. 우리나라는 국토가 좁은 반면 인구밀도가 높고, 인구의 도시집중화로 공동주택의 주거비율이 높은 추세이기 때문에 최근 공동주택단지는 초고층화, 대형화가 되고 있으며, 이로 인해 급수 급탕에 대한 사용패턴도 변화하고 있다. 하지만 현재 급수 급탕에 대한 설계 자료는 대부분 외국의 설계 기준과 현장 경험치에 의해 산출된 데이터에 의존하고 있으며, 사용실태에 대한 기초자료가 부족한 실정이며, 이로 인해 급수 급탕 설비 설계 시 과대 또는 과소 설계가 되는 문제가 발생하고 있다. 본 연구에서는 공동주택의 공급자 측 급탕 열 공급환경과 사용자측 열사용량을 측정하여, 급탕부하가 발생하는 시간과 사용 실태 및 패턴을 파악함으로써, 효율적인 공급자 측 급탕설비 설계와 관리를 위한 기초자료를 제시하고자 한다.