• 제목/요약/키워드: Gathering

검색결과 1,670건 처리시간 0.13초

그루브를 이용한 표면형상변형 동특성 변경법 :HDD 커버에 대한 적용 (Structural Dynamics Modification Using Surface Grooving Technique : Application to the HDD Cover model)

  • 박미유;박영진;박윤식
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2004년도 추계학술대회논문집
    • /
    • pp.826-829
    • /
    • 2004
  • Structural Dynamics Modification is very effective technique to improve structure's dynamic characteristics by adding or removing auxiliary structures, changing material property, changing shape of structure. In this research, using the surface grooving technique, shape of base structure was changed to improve its first natural frequency. Utilizing the result of frequency variation analysis, groove shape was formed gathering the many small embossing elements. For this process, Criterion Factor was introduced. To reduce its amount of calculation, the range of target area was restricted to their neighboring area and initial grooving point was selected using high-strain energy. This surface grooving technique was successfully applied to the HDD cover model.

  • PDF

무선 센서 네트워크에서 에너지 효율적이고 멀티미디어 트래픽에 적합한 MAC 프로토콜 (Energy Efficient and Multimedia Traffic Friendly MAC Protocol in Wireless Sensor Networks)

  • 김성철;김혜윤;김중재
    • 한국멀티미디어학회논문지
    • /
    • 제19권8호
    • /
    • pp.1460-1465
    • /
    • 2016
  • In this paper, we propose an energy efficient and multimedia traffic friendly MAC protocol (EEMF-MAC) that controls sender's wakeup period based on the data packet's transmission urgency and the receiver's wakeup periods based on the received data packet traffic loads. The protocol is useful for applications such as object tracking, real time data gathering, in which priority-based packet transmission is required. The basic idea of EEMF-MAC is that it uses the priority concept with transmission urgency of sender's data packet to reduce the transmission delay of the urgent data and it also uses duty cycling technique in order to achieve energy efficiency. EEMF-MAC showed a better performance in energy efficiency and packet transmission delay compared to existing protocols, RI-MAC and EE-RI-MAC.

계산에 기초한 하드웨어 도입 규모산정 방식 연구 (The Study on Hardware Sizing Method Based on the Calculating)

  • 나종회;최광돈;정해용
    • 한국IT서비스학회지
    • /
    • 제5권1호
    • /
    • pp.47-59
    • /
    • 2006
  • According to the policy for "e-Korea construction" of Korean government, Investment of information system during the past decade are dramatically increasing. More than a half of this investment is cost of hardware infrastructure. So, accurate hardware sizing are essential for higher efficiency of investment. Accurate hardware sizing benefits are generally viewed in terms of the avoidance of excess equipment and lost opportunity costs by not being able to support business needs. Unfortunately, however, little research effort to make the hardware sizing methodology are doing. We propose a sizing method for information system in public sector. This method is determinate empirical study that are gathering and analyzing cases, making method and reviewing expert. Finally we are proposed calculating method for hardware components that is CPU, memory, internal and external disk according to the application system type which is OLTP, Web, WAS. Our study certainly will act as a catalyst for higher investment-efficiency of the future information programs in public sector.

제조 환경에서 PLC 데이터의 실시간 수집 및 분석 (Real Time Gathering and Analysis of PLC Data in Manufacturing environoment)

  • 고석빈;김재훈;명제석;류관희
    • 한국정보처리학회:학술대회논문집
    • /
    • 한국정보처리학회 2019년도 추계학술발표대회
    • /
    • pp.350-353
    • /
    • 2019
  • 4차 산업혁명 시대에 접어들면서 제조업은 공장 내 설비와 기계에 Arduino 센서를 설치하여 데이터를 실시간으로 수집, 분석하는 스마트 팩토리로 전환되었다. 이에 Digital Twin이라는 개념이 생겨난다. Digital Twin이란 컴퓨터에 현실 속 사물의 쌍둥이를 만들고, 현실에서 발생할 수 있는 상황을 컴퓨터로 시뮬레이션 함으로써 결과를 예측하는 기술을 말한다. 본 논문에서는 제조환경에서 발생할 수 있는 물리적인 동작 환경을 시뮬레이션하고, PLC 데이터와 수집된 센서 데이터를 이용하여 실시간으로 공정과정을 모니터링할 수 있는 Virtual Digital Twin System을 제안한다. 본 시스템은 PLC Hardware와 Arduino 센서, 사용자가 접근할 수 있는 PC 및 Web Page로 이루어진다. 제조환경에서의 PLC Hardware를 3D 모델링하여 제공한다. 또한 기기에 부착되어있는 Arduino 센서에서 발생하는 데이터를 수집하고, 분석하여 후에 발생할 수 있는 결함에 대하여 대처할 수 있도록 한다.

이동에이전트를 이용한 분산 정보수집 시스템 (Distributed Information Gathering System using Mobile Agents)

  • 공용해;최인석
    • 한국정보처리학회:학술대회논문집
    • /
    • 한국정보처리학회 2001년도 춘계학술발표논문집 (상)
    • /
    • pp.305-308
    • /
    • 2001
  • 객체 컴포넌트 기반 웹 정보 저장/검색 시스템인 IHWA 시스템의 정보 수집 효율을 중대하기 위하여 이동에이전트를 이용한 분산 정보수집 시스템을 구현하였다. 분산 정보수집 시스템은 이동 에이전트를 약간의 제약을 갖는 준 협약 사이트로 파견하여 XML 문서를 파싱하고, 정보를 추출하여 IHWA시스템의 데이터베이스에 저장하도록 한다. 이동 에이전트는 준 협약 사이트에서 XML파서를 활용하여 필요한 정보만을 수집하여 전송하므로 정보의 전송량을 최소화하여 네트워크의 부하를 줄일 수 있으며, 동시에 IHWA 시스템의 처리 부하를 크게 줄일 수 있다. 또한 향후 원격 사이트의 고유한 문서 특성에 적합한 정보 추출이 가능하도록 확장할 수 있다.

  • PDF

자동화된 추론을 이용한 퍼지 조건연산자의 비교 분석 (Comparison of Fuzzy Implication Operators using Automated Reasoning)

  • 김용기
    • 한국지능시스템학회논문지
    • /
    • 제5권4호
    • /
    • pp.18-32
    • /
    • 1995
  • 퍼지 정보 검색 기법을 이용한 가중치 선정 전락은,주어진 입력 문제로 부터 가중치의 패턴과 가중치를 자동적으로 선정함으로써, 추론 시간과 공간을 줄인다. 퍼지 가중치 선정 전략은 퍼지 삼각 관계곱 및 퍼지 신속관계 알고리즘을 사용하기 때문에 선택하는 퍼지 조건연산자와 $-cut에 따라서 결론을 추출하는 시간과 추론 단계의 수가 틀린다. 본 논문에서는, 퍼지 정보 검색을 이용한 추론 전략의 조절 방법에 대하여 개괄적으로 보이고, 잘 알려진 블럭 문제에 적용하여 주어진 영역에서 가장 적합한 퍼지 조건연산자와 $-cut을 선정한다.

  • PDF

동시부하율을 고려한 전기로의 수요관리 잠재량 산출 (Calculation of DSM's Latent capacity for arc-furnace Considered with the Same Time Load Factor)

  • 손학식;김인수;임상국;김형중;허동렬;김재철
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2004년도 하계학술대회 논문집 A
    • /
    • pp.82-84
    • /
    • 2004
  • This paper has calculated DSM's latent capacity through a survey investigating electric arc furnaces in over 2,000 toe companies and related organizations. The latent capacity of DSM calculated with the same time load factor is considered in this paper. The time load factor depends on the probability of each electric arc furnace of the value to work and the consideration of experts and technician's experience. Also, this paper verifies the reliability and application of unposed capacity which compared the old latent capacity of Load Management with KEMCO and KEPCO's Direct Load Control gathering capacity.

  • PDF

성과중심교육에서 학생평가 (Assessment in Outcome-Based Education)

  • 임선주
    • 의학교육논단
    • /
    • 제15권1호
    • /
    • pp.25-30
    • /
    • 2013
  • Assessment plays a vital role in outcome-based education (OBE). This article describes the characteristics of assessment and appropriate assessment instruments for measuring learning outcomes in OBE. Assessment in OBE needs to be formative, continuous, and frequent. Miller's pyramid is useful for selecting the appropriate assessment instruments to reflect a specific outcome; different methods can be applied to evaluate one outcome. Outcomes and competency mean that student must 'do'; therefore, performance tests are emphasized. Qualitative methods as well as quantitative methods are used to evaluate the outcomes of areas such as professionalism or ethics. An absolute criterion-based standard is usually applied to decide whether students pass or fail, but the decision should be based on gathering value judgments and reaching consensus. Active participation of faculty members and students in assessment is crucial.

A Study of Supersonic Combustion using Various Liquid Hydrocarbon Fuels

  • Hashimoto, Susumu;Hiramoto, Ayumu;Tsue, Mitsuhiro;Kono, Michikata;Ishikawa, Yuta;Suzuki, Shunsuke;Ujiie, Yasushige
    • 한국추진공학회:학술대회논문집
    • /
    • 한국추진공학회 2008년 영문 학술대회
    • /
    • pp.340-345
    • /
    • 2008
  • Liquid hydrocarbon fuels are gathering increasing attention as candidates for a scramjet engine fuel. Experimental researches on supersonic combustion of kerosene have been conducted in model scramjet combustors. Through these works, understanding of combustion characteristics of kerosene have been revealed on some level, and so we decided to work on other kinds of liquid hydrocarbon fuels in order to explore effects of fuel properties on supersonic combustion performances, especially self-ignition and flame-holding. In addition, comparing the results of new fuels with kerosene, the relationship between fuel properties and supersonic combustion characteristics was discussed.

  • PDF

틸팅 열차의 현가장치 최적화 (Optimizing the suspension system of the tilting train)

  • 김정범;박태원;윤지원;정성필;구동회
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2008년도 추계학술대회 논문집
    • /
    • pp.1703-1709
    • /
    • 2008
  • The TTX(Tilting Train eXpress) has tilting mechanism that is not existed in the previous train. So, the characteristics of suspension will be different from others. For this reason, TTX needs to be investigated about the suspension in contrast with the previous suspension system. The 2nd damping ratio is very important for a tilting mechanism. Proper value of suspension characteristics should be suggested for the tilting train. In this paper, the optimization of suspension systems for TTX model is introduced by using Design of Experiments (DOE) which is the design of all information-gathering exercises where variation is present. At first, the dynamics model is made for evaluating characteristics of suspension system. Second, using evaluated value, suspension characteristics are analyzed for sensitivity analysis. Finally, using the result of a sensitivity analysis, the suspension systems are optimized.

  • PDF