• 제목/요약/키워드: real-time task

검색결과 761건 처리시간 0.026초

Energy harvesting and power management of wireless sensors for structural control applications in civil engineering

  • Casciati, Sara;Faravelli, Lucia;Chen, Zhicong
    • Smart Structures and Systems
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    • 제10권3호
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    • pp.299-312
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    • 2012
  • The authors' research efforts recently led to the development of a customized wireless control unit which receives the real-time feedbacks from the sensors, and elaborates the consequent control signal to drive the actuator(s). The controller is wireless in performing the data transmission task, i.e., it receives the signals from the sensors without the need of installing any analogue cable connection between them, but it is powered by wire. The actuator also needs to be powered by wire. In this framework, the design of a power management unit is of interest only for the wireless sensor stations, and it should be adaptable to different kind of sensor requirements in terms of voltage and power consumption. In the present paper, the power management efficiency is optimized by taking into consideration three different kinds of accelerometers, a load cell, and a non-contact laser displacement sensor. The required voltages are assumed to be provided by a power harvesting solution where the energy is stored into a capacitor.

반발력을 생성하는 햅틱장비를 이용한 가상의 점토 모델링에 관한 연구 (On the Virtual Clay Modeling Using a Force Reflecting Haptic Manipulator)

  • 채영호
    • 한국CDE학회논문집
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    • 제4권1호
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    • pp.12-18
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    • 1999
  • A deformable non-Uniform Rational B-Spline (NURBS) based volume is programed for the force reflecting exoskeleton haptic device. In this work, a direct free form deformation (DFFD) technique is applied for the realistic manipulation. In order to implement the real-time deformation, a nodal mapping technique is used to connect points on the virtual object with the NURBS volume. This geometric modeling technique is ideally incorporated with the force reflecting haptic device as a virtual interface. The results in this work introduce details for the complete set-up for the realistic virtual clay modeling task with force feedback. The force reflecting exoskeleton haptic manipulator, coupled with a supporting PUMA 560 manipulator and the virtual clay model are integrated with the graphics display, and results show that the force feedback from the realistic physically based virtual environment can greately enhance the sense of immersion.

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PDA 기반 음성 인식기 개발 (Development of a Speech Recognizer on PDAs)

  • 구명완;박성준;손단영;한기수
    • 대한음성학회:학술대회논문집
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    • 대한음성학회 2006년도 춘계 학술대회 발표논문집
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    • pp.33-36
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    • 2006
  • This paper describes a speech recognizer implemented on PDAs. The recognizer consists of feature extraction module, search module and utterance verification module. It can recognize 37 words that can be used in the telematics application and fixed-point operation is performed for real-time processing. Simulation results show that recognition accuracy is 94.5% for the in-vocabulary words and 56.8% for the out-of-task words.

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Bayesian Learning through Weight of Listener's Prefered Music Site for Music Recommender System

  • Cho, Young Sung;Moon, Song Chul
    • Journal of Information Technology Applications and Management
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    • 제23권1호
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    • pp.33-43
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    • 2016
  • Along with the spread of digital music and recent growth in the digital music industry, the demands for music recommender are increasing. These days, listeners have increasingly preferred to digital real-time streamlining and downloading to listen to music because it is convenient and affordable for the listeners to do that. We use Bayesian learning through weight of listener's prefered music site such as Melon, Billboard, Bugs Music, Soribada, and Gini. We reflect most popular current songs across all genres and styles for music recommender system using user profile. It is necessary for us to make the task of preprocessing of clustering the preference with weight of listener's preferred music site with popular music charts. We evaluated the proposed system on the data set of music sites to measure its performance. We reported some of the experimental result, which is better performance than the previous system.

FlexRay 프로토콜에서 플랫폼 구성 변수의 자동 생성에 관한 연구 (Study on Automatic Generation of Platform Configuration Register in FlexRay Protocol)

  • 양재성;박지훈;이석;이경창;최광호
    • 대한임베디드공학회논문지
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    • 제7권1호
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    • pp.41-52
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    • 2012
  • Recently, FlexRay was developed to replace controller area network (CAN) protocol in chassis networking systems, to remedy the shortage of transmission capacity and unsatisfactory real-time transmission delay of conventional CAN. FlexRay network systems require correct synchronization and complex scheduling parameters. However, because platform configuration register (PCR) setting and message scheduling is complex and bothersome task, FlexRay is more difficult to implement in applications than CAN protocol. To assist a network designer for implementing FlexRay cluster, this paper presents an analysis of FlexRay platform configuration register and automatic generation program of PCR. To demonstrate the feasibility of the automatic generation program, we evaluated its performance using experimental testbed.

Estimation of Insulated-gate Bipolar Transistor Operating Temperature: Simulation and Experiment

  • Bahun, Ivan;Sunde, Viktor;Jakopovic, Zeljko
    • Journal of Power Electronics
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    • 제13권4호
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    • pp.729-736
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    • 2013
  • Knowledge of a power semiconductor's operating temperature is important in circuit design and converter control. Designing appropriate circuitry that does not affect regular circuit operation during virtual junction temperature measurement at actual operating conditions is a demanding task for engineers. The proposed method enables virtual junction temperature estimation with a dedicated modified gate driver circuit based on real-time measurement of a semiconductor's quasi-threshold voltage. A simulation was conducted before the circuit was designed to verify the concept and to determine the basic properties and potential drawbacks of the proposed method.

주기 태스크의 종료시간을 보장하기 위한 확장된 혼합 실시간 스케쥴링 알고리즘 (Expended Hybrid Real-Time Scheduling Algorithm for guard Deadline of An Periodic Task)

  • 한대만;최만억;구용완
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 1999년도 가을 학술발표논문집 Vol.26 No.2 (3)
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    • pp.161-163
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    • 1999
  • 본 논문은 고정 우선순위를 가지는 주기 태스크와 동적으로 발생하는 비주기 태스크를 스케쥴링하는 방법으로 슬랙 스틸링(slack stealing) 알고리즘을 소개하고 발생되는 문제점으로부터 새로운 알고리즘을 제시한다. 기존의 실시간 스케쥴링 알고리즘을 RM 스케쥴링에 의해 할당된 주기 태스크의 우선순위가 동적으로 발생하는 비주기 태스크의 수행으로 인한 주기 태스크들간의 긴급함에 적절하게 대응하지 못하고 주기 태스크들이 자신의 제한시간을 넘길 수 있다. 이는 슬랙 스틸링(slack stealing) 알고리즘에서 슬랙 타임을 구하는 함수의 한 요소로서 주기 태스크의 필요 계산시간 값이 긴급하지 않은 상위 우선 순위 태스크의 계산시간 까지 포함하는데 있다. 따라서 제안한 확장된 실시간 스케쥴링 알고리즘은 RM 스케쥴링에 의한 스케쥴링 가능성을 위배하지 않으면서 동적으로 발생하는 비주기적 태스크로부터 긴급도의 변화에 적응할 수 있는 우선 순위 체제의 알고리즘을 제시하고, 제안한 알고리즘이 다른 실시간 알고리즘보다 성능 개선이 있음을 모의 실험을 통하여 증명한다.

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3관절 매니퓰레이터의 일반적 조합에 대한 역기구학적 폐형해 (Closed Form Inverse Kinematic Solutions for General Combination of Three-Joint Manipulator)

  • 한규범
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1995년도 춘계학술대회 논문집
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    • pp.363-368
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    • 1995
  • A general method of solving inverse kinematics of three-joint manipulator composed of revolute joints or prismatic joints or combinations of those joints is presented in this study. In completing real-time control, it is very important to obtain the closed form solutions of inverse kinematics rather than iterative numerical solutions, because iterative numerical solutions are generally much slower than the corresponding closed form solutions. If it is possible to obtain the inverse kinematic solutions for general cases of considering twist anlges and offsets, the manipulator work space can be designed and enlarged more effciently for specific task. Moreover, in idustrial manipulators, the effect of main three joints is larger than that of the other three joints related to orientation in the view of work space. Therfore the solutions of manin three-joint are considered. Even The inverse kinematic equations are complicatedly coupled, the systematical solving process by using symbolic calculation is presented.

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라이노 로보트 매니퓰레이터의 동특성 미 실시간 최적추적제어에 관한 연구 (A Study on Dynamics Analysis and Real Time Optimal Tracking Control& Rhino Robotic Manipulator)

  • 한성현;이만형
    • 한국정밀공학회지
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    • 제6권1호
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    • pp.52-74
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    • 1989
  • In general, the state of system can be effected by external noise and observed only through a noisy channel. Therefore we use the estimation technigue for the information of state of the system effected by noise. There are many filters such as kalman-Buchy filter, kalman filter, Extended Kalman filter algorithm, cononlinear, extended Kalman filter algorithm to the estimation of parameters is very useful and has a long history. Also a considerable number of applications of this method has been reported. In this paper, the robot control system is treated in stochastic optimal control because of the robots doing a complicated and accurate task in inapproate environment. We have conclusion that error covariance is converged and the stability of filtering is obtained.

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ERP 시스템 구축 관련 조직변화관리 지원을 위한 e-러닝 활용전략 (The Strategic Use of e-Learning for ERP Related Organizational Change Management)

  • 김영렬;한대문
    • 한국산업정보학회논문지
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    • 제11권5호
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    • pp.132-140
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    • 2006
  • ERP 시스템 교육은 새로운 시스템에 대한 구성원들의 교육 및 연수과정에서 많은 문제점을 초래할 수도 있다. 그러한 문제점을 해결하기 위한 방안으로 시간, 장소 등에 구애받지 않고 교육을 할 수 있는 e-러닝을 활용한 ERP 교육이 대두되었다. 본 연구에서는 ERP 시스템 구축관련 조직변화관리 지원을 위한 e-러닝 활용전략으로 ERP 교육컨텐츠의 질 개선, 상호작용(피드백)의 강화, 블렌디드 러닝의 활용, ERP 시스템과 e-러닝 시스템 연계 모델 등을 제시하였다.

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