• 제목/요약/키워드: MultiPath

검색결과 1,442건 처리시간 0.027초

JORDAN 𝒢n-DERIVATIONS ON PATH ALGEBRAS

  • Adrabi, Abderrahim;Bennis, Driss;Fahid, Brahim
    • 대한수학회논문집
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    • 제37권4호
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    • pp.957-967
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    • 2022
  • Recently, Brešar's Jordan {g, h}-derivations have been investigated on triangular algebras. As a first aim of this paper, we extend this study to an interesting general context. Namely, we introduce the notion of Jordan 𝒢n-derivations, with n ≥ 2, which is a natural generalization of Jordan {g, h}-derivations. Then, we study this notion on path algebras. We prove that, when n > 2, every Jordan 𝒢n-derivation on a path algebra is a {g, h}-derivation. However, when n = 2, we give an example showing that this implication does not hold true in general. So, we characterize when it holds. As a second aim, we give a positive answer to a variant of Lvov-Kaplansky conjecture on path algebras. Namely, we show that the set of values of a multi-linear polynomial on a path algebra KE is either {0}, KE or the space spanned by paths of a length greater than or equal to 1.

무인비행체의 유사시 대안 경로 선택을 위한 DEVS 기반 디지털 트윈 시뮬레이션 환경 모델링 (DEVS-based Digital Twin Simulation Environment Modeling for Alternative Route Selection in Emergency Situations of Unnamed Aerial Vehicles)

  • 권보승;정상원;노영단;이종식;한영신
    • 한국멀티미디어학회논문지
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    • 제25권8호
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    • pp.1007-1021
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    • 2022
  • Autonomous driving of unmanned aerial vehicles may have to pay expensive cost to create and switch new routes if unexpected obstacles exist or local map updates occured by the control system due to incorrect route information. Integrating digital twins into the path-following process requires more computing resources to quickly switch the wrong path to an alternative path, but it can quickly update the path during flight. In this study, we design a DEVS-based simulation environment which can modify optimized paths through short-term simulation of multi-virtual UAVs for applying digital twin concepts to path follow. Through simulation, we confirmed the possibility of increasing the mission stability of UAV.

경험적 방법에 기초한 무인 반송차의 항법 알고리즘 (A Heuristic Based Navigation Algorithm for Autonomous Guided Vehicle)

  • 차영엽;권대갑
    • 한국정밀공학회지
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    • 제12권1호
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    • pp.58-67
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    • 1995
  • A path planning algorithm using a laser range finder are presented for real-tiem navigation of an autonomous guided vehicle. Considering that the laser range finder has the excellent resolution with respect to angular and distance measurements, a sophisticated local path planning algorithm is achieved by using the human's heuristic method. In the case of which the man knows not rhe path, but the goal direction, the man forwards to the goal direction, avoids obstacle if it appears, and selects the best pathway when there are multi-passable ways between objects. These heuristic principles are applied to the path decision of autonomous guided vehicle such as forward open, side open and no way. Also, the effectiveness of the established path planning algorithm is estimated by computer simulation in complex environment.

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Mobile Robot navigation using an Multi-resolution Electrostatic Potential Filed

  • Kim, Cheol-Taek;Lee, Ju-Jang
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2004년도 ICCAS
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    • pp.690-693
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    • 2004
  • This paper proposes a multi-resolution electrostatic potential field (MREPF) based solution to the mobile robot path planning and collision avoidance problem in 2D dynamic environment. The MREPF is an environment method in calculation time and updating field map. The large scale resolution map is added to EPF and this resolution map interacts with the small scale resolution map to find an optimal solution in real time. This approach can be interpreted with Atlantis model. The simulation studies show the efficiency of the proposed algorithm.

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다중경로 분석을 위한 전력선 네트워크 기술 방법에 관한 연구 (A Study of Power Line Network Description Method for Multi path Analysis)

  • 오휘명;최성수;이원태;김관호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 D
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    • pp.2986-2988
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    • 2005
  • To improve the reliability of power-line communication systems, the measurement and analysis has been proceeded in many power-line channel environments. In spite of the wired channel, power line channel has many multi-paths that are changing with load-variation, line-interconnection, impedance mismatching and so on. We accordingly need an analysis method based on the multi-path channel impulse response. Recently, a method to describe the homogeneous Power-line network has been published[1]. In this paper the modified method that can describe both the homogeneous and non -homogeneous power-line network has presented.

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레이더용 다채널 수신기 설계 및 제작 (The Design and Fabrication of Multi-Channel Receiver for Radar System)

  • 김완식;이한영
    • 전기학회논문지
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    • 제61권11호
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    • pp.1671-1675
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    • 2012
  • In this paper, we fabricate multi-channel receiver for radar system. This receiver at X-band can be received 8 signal of an identical characteristic, dynamic range has more than 80[dB]. To process direct received signals, this system has the built-in two digital de-modulators which offer the minimum loss on the receiving signal path and has high stability by adding Built-In Test. The gain, noise figure, difference of amplitude and phase on the signal path is respectively $14{\pm}2$[dB], 19[dB], ${\pm}2$[dB], $10^{\circ}$ and below.

다중센서를 이용한 무인자동차 제어시스템 (Automatic Automobile Control System with Multi-Sensor)

  • 한창우;최원식
    • 한국산업융합학회 논문집
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    • 제4권3호
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    • pp.339-347
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    • 2001
  • Automatic automobile has been studied as the alternative energy system and the production flow automation device recently. But this is dependent on the import production, and its position cannot be controlled free from the fixed path. It is difficult to control the automobile position because of the eccentricity of inertia monent, slip and roughness between wheel and road surface. This problems is solved for the controller to be feedbacked the data of the multi-sensor system consisting of the rotary encoder and electronic compass. The proportional Integrated controller in the modified Ziegler-Nichols method is made up with Hitachi 7034 microprocessor. To the real time control the mechanical, electrical and electronic hardware and software device is produced by myself. The RF data of automobile speed and position is supplied to the remote PC to be displayed the automobile condition. By the experinent of the forward, spin, point path planning, it is known for autombile.

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Performance Evaluation of the Physical Layer of the DSRC Operating in 5.8 GHz Frequency Band

  • Lee, Byung-Seub;Yim, Choon-Sik;Ahn, Dong-Hyun;Oh, Deock-Gil
    • ETRI Journal
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    • 제23권3호
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    • pp.121-128
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    • 2001
  • In this paper, the theoretical as well as experimental results of BER characteristics of three different modulation schemes, ASK, FSK and BPSK, in a multi-path Rician channel are addressed. These BER characteristics are analyzed as a function of $E_b/N_o$ and the power ratio of the line of sight (LOS) component to the Rayleigh scattered component. The theoretical as well as computer simulation results shows the ASK is the most suitable modulation scheme for the dedicated short range communication (DSRC) in terms of implemental cost and system complexity. The decision feedback equalizer is proved to be very effective in canceling the multi-path interference in the DSRC channel environment. The simulation result of the equalized ASK, reveals the performance enhancement achievable with decision feedback (DFE) equalizer for the first generation DSRC system. The multi-ray DSRC channel model is also provided to predict the received carrier power and fluctuation, which are quite dependent on the surroundings of a cell.

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Simple Node 망에서 QoS 향상을 위한 다중경로 망 요약 기법 (Multi-path Topology Aggregation Scheme of Simple Node Topology for QoS Improvement)

  • 김남희;김변곤
    • 융합보안논문지
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    • 제8권2호
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    • pp.95-102
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    • 2008
  • 본 논문에서는 simple node 토폴로지의 망 정보를 효율적으로 요약함으로써 망에서의 호 성공률, 액세스 타임을 향상시켜 망의 전체적인 QoS를 향상시키기 위한 토폴로지 요약 기법을 제안하였다. 제안된 기법에서는 대역폭과 지연 파라미터를 중심으로 라인 세그먼트를 이용하여 경계노드 사이의 다중 경로 정보를 요약함으로써 토폴로지 요약 정보를 줄이고 다중링크 요약에 유연성을 부여하여 망의 성능을 향상시킬 수 있었다. 제안된 기법의 성능을 평가하기 위해 기존의 simple node 토폴로지 요약 기법과 호 성공률, 접근시간에 대하여 컴퓨터 시뮬레이션을 통해 비교 분석하였다.

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