• 제목/요약/키워드: Systems approach

검색결과 10,004건 처리시간 0.031초

Position Location of Mobile Terminal in Wireless MIMO Communication Systems

  • Li, Ji;Conan, Jean;Pierre, Samuel
    • Journal of Communications and Networks
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    • 제9권3호
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    • pp.254-264
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    • 2007
  • A promising approach to improve the performance of mobile location system is the use of antenna arrays in both transmitter and receiver sides. Using advanced array signal processing techniques, such multiple-input multiple-output (MIMO) communication systems can offer more mobile location information by exploiting the spatial properties of the multipath channel. In this paper, we propose a novel approach to determine the position of mobile terminal based on estimated multipath signal parameters using only one base station in MIMO communication systems. This approach intends to minimize the error occurring from the estimation of multiple paths and gives an optimal estimation of the position of mobile terminal by simultaneously calculating a set of nonlinear location equations. This solution breaks the bottleneck of conventional mobile location systems which have to require multilateration of at least three base stations.

혼합 군에 대한 확률적 란체스터 모형의 정규근사 (Gaussian Approximation of Stochastic Lanchester Model for Heterogeneous Forces)

  • 박동현;김동현;문형일;신하용
    • 대한산업공학회지
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    • 제42권2호
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    • pp.86-95
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    • 2016
  • We propose a new approach to the stochastic version of Lanchester model. Commonly used approach to stochastic Lanchester model is through the Markov-chain method. The Markov-chain approach, however, is not appropriate to high dimensional heterogeneous force case because of large computational cost. In this paper, we propose an approximation method of stochastic Lanchester model. By matching the first and the second moments, the distribution of each unit strength can be approximated with multivariate normal distribution. We evaluate an approximation of discrete Markov-chain model by measuring Kullback-Leibler divergence. We confirmed high accuracy of approximation method, and also the accuracy and low computational cost are maintained under high dimensional heterogeneous force case.

Plastic energy approach prediction of fatigue crack growth

  • Maachou, Sofiane;Boulenouar, Abdelkader;Benguediab, Mohamed;Mazari, Mohamed;Ranganathan, Narayanaswami
    • Structural Engineering and Mechanics
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    • 제59권5호
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    • pp.885-899
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    • 2016
  • The energy-based approach to predict the fatigue crack growth behavior under constant and variable amplitude loading (VAL) of the aluminum alloy 2024 T351 has been investigated and detailed analyses discussed. Firstly, the plastic strain energy was determined per cycle for different block load tests. The relationship between the crack advance and hysteretic energy dissipated per block can be represented by a power law. Then, an analytical model to estimate the lifetime for each spectrum is proposed. The results obtained are compared with the experimentally measured results and the models proposed by Klingbeil's model and Tracey's model. The evolution of the hysteretic energy dissipated per block is shown similar with that observed under constant amplitude loading.

임베디드 시스템에서의 객체 분류를 위한 TVM기반의 성능 최적화 연구 (TVM-based Performance Optimization for Image Classification in Embedded Systems)

  • 허청환;예민해;신익희;이대우
    • 대한임베디드공학회논문지
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    • 제18권3호
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    • pp.101-108
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    • 2023
  • Optimizing the performance of deep neural networks on embedded systems is a challenging task that requires efficient compilers and runtime systems. We propose a TVM-based approach that consists of three steps: quantization, auto-scheduling, and ahead-of-time compilation. Our approach reduces the computational complexity of models without significant loss of accuracy, and generates optimized code for various hardware platforms. We evaluate our approach on three representative CNNs using ImageNet Dataset on the NVIDIA Jetson AGX Xavier board and show that it outperforms baseline methods in terms of processing speed.

고속 프로그램형 논리 제어기 구현을 위한 래더 다이어그램 해석 방법 (A Translation Method of Ladder Diagram for High-Speed Programmable Logic Controller)

  • 김형석;장래혁;권욱현
    • 제어로봇시스템학회논문지
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    • 제5권1호
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    • pp.33-38
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    • 1999
  • This paper proposes a translation approach for PLCs (Programmable logic controllers) converting ladder diagrams directly to native codes, and describes detailed steps of the method followed by performance evaluation. A general-purpose DSP (Digital signal processor) based implementation validates the approach as well. A benchmark test shows that the Proposed translation framework fairly speeds up execution in comparison with the existing interpretation approach.

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Tool selection problem in flexible manufacturing systems

  • Kato, Kiyoshi
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 22-24 Oct. 1991
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    • pp.1553-1556
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    • 1991
  • This paper deals with a problem on the selection of alternative tools in a flexible manufacturing system (FMS) where a lot of tools are required to produce a large variety of product items. An approach using branch and bound method is proposed to minimize a total number of tools required through the optimal use of the alternative tools. In this approach, tools are initially divided into tool subgroups based on graph theory for the purpose of the effective search of the optimal solution. A small example is also presented to highlight the effectiveness of the proposed approach.

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Evolutionary Approach for Traveling Salesperson Problem with Precedence Constraints

  • 문치웅;윤영수
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2007년도 춘계학술대회 학술발표 논문집 제17권 제1호
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    • pp.305-308
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    • 2007
  • In this paper we suggest an efficient evolutionary approach based on topological sort techniques for precedence constrained TSPs. The determination of optimal sequence has much to offer to downstream project management and opens up new opportunities for supply chains and logistics. Experimental results show that the suggested approach is a good alternative to locate optimal solution for complicated precedence constrained sequencing as in optimization method for instance.

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실시간 시뮬레이션을 위한 병렬적분 (Parallel Integration for Real-Time Simulation)

  • 이운성
    • 한국자동차공학회논문집
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    • 제2권1호
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    • pp.106-115
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    • 1994
  • A parallel integration approach is proposed for real-time simulation of controlled mechanical systems. The proposed approach, which employs the dual-rate integration method in a parallel computing environment, is developed to deal with stiffness and high frequency characteristics of the controlled mechanical systems effectively. Numerical experiments are performed to demonstrate the effectiveness of the approach in shared memory multiprocessors, Alliant FX/8 and Alliant FX/80.

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A New Variant of Correlation Approach for ARMA Model Identification

  • Seong, Sang-Man
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.1903-1906
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    • 2005
  • We proposed a new variant of correlation approach for ARMA model. The proposed method is is intended to make the current prediction error uncorrelated with the past one. In the investigation of the properties, the uniqueness, consistency and asymptotic normality of the estimate are shown. Via simulation results, we show that the proposed method give good estimates for various systems.

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Energy Efficient Transmit and Receive Strategy for Green Communications: K users extension

  • Oh, Changyoon
    • 한국컴퓨터정보학회논문지
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    • 제21권10호
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    • pp.37-42
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    • 2016
  • We investigate multi user joint rate scheduling and power allocation problem for a delay sensitive CDMA systems. First, we characterize the existing two user joint rate scheduling and power allocation. We then extend the problem to the case of the multi user systems. In general, there is no simple optimum solution for the multi user scheduling problem. To that end, we propose a sub optimum solution, termed 'virtual user approach'. We show the performance of the virtual user approach to verify the benefit of complexity.