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Novel hybrid approaches based on evolutionary strategy for streamflow forecasting in the Chellif River, Algeria

ACTA GEOPHYSICA 2020年第1期68卷 167-180页

作者： Zakhrouf, Mousaab Bouchelkia, Hamid Stamboul, Madani Kim, Sungwon Univ Tlemcen Fac Technol Dept Hydraul URMER Lab Tilimsen Algeria Amar Telidji Univ Fac Architecture & Civil Engn Dept Civil Engn Res Lab Water Resources Soil & Environm Laghouat Algeria Dongyang Univ Dept Railroad Construct & Safety Engn Yeongju 36040 South Korea

In this study, the feedforward neural networks (FFNNs) were proposed to forecast the multi-day-ahead streamflow. The parameters of FFNNs model were optimized utilizing genetic algorithm (GA). Moreover, discrete wavelet transform was utilized to enhance the accuracy of FFNNs model's forecasting. Therefore, the wavelet-based feedforward neural networks (WFFNNs-GA) model was developed for the multi-day-ahead streamflow forecasting based on three evolutionary strategies [i.e., multi-input multi-output (MIMO), multi-input single-output (MISO), and multi-input several multi-output (MISMO)]. In addition, the developed models were evaluated utilizing five different statistical indices including root mean squared error, signal-to-noise ratio, correlation coefficient, Nash-Sutcliffe efficiency, and peak flow criteria. Results provided that the statistical values of WFFNNs-GA model based on MISMO evolutionary strategy were superior to those of WFFNNs-GA model based on MISO and MIMO evolutionary strategies for the multi-day-ahead streamflow forecasting. Results indicated that the performance of WFFNNs-GA model based on MISMO evolutionary strategy provided the best accuracy. Results also explained that the hybrid model suggested better performance compared with stand-alone model based on the corresponding evolutionary strategies. Therefore, the hybrid model can be an efficient and robust implement to forecast the multi-day-ahead streamflow in the Chellif River, Algeria.

关键词： Daily streamflow forecasting Wavelet transform Feed forward neural networks multi-input multi-output multi-input single-output multi-input several multi-output Chellif River

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Performance of MIMO IEEE802.11n WLAN in Presence of QPSK Jammer with Inphase/Quadrature Origin Offsets

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WIRELESS PERSONAL COMMUNICATIONS 2020年第1期113卷 555-574页

作者： Shaheen, Ehab M. Mil Tech Coll Elect Warfare Dept Cairo Egypt

In this paper a novel jamming technique is presented. The idea of the proposed jamming technique is based on adding inphase and quadrature impairments to the jamming signal. The jammer is simply a quadrature phase shift keying signal. The bit error rate probability (BER) of the proposed jamming signal is derived analytically and validated with the aid of the software defined radio SystemVue design software. The standard multi input multi output (MIMO) wireless local area network (WLAN) IEEE802.11n communication system is chosen as the victim system. Its BER performance is simulated in the presence of the proposed jamming signal in multipath fading channel. Finally, the efficiency of the proposed jamming signal on the MIMO WLAN IEEE802.11n communication system is practically measured in the laboratory where a practical experiment is held and the efficiency of the proposed jamming signal is compared with the traditional single tone jamming signal. It will be shown practically that the proposed jamming technique outperforms the traditional single tone jamming signal by nearly 15 dBm on the impact of efficiently jam the MIMO WLAN IEEE802.11n communication system.

关键词： multi-input multi-output IEEE802 11n Jamming Bit error rate probability Inphase and quadrature offsets

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A Sequential Subspace Method for Millimeter Wave MIMO Channel Estimation

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2020年第5期69卷 5355-5368页

作者： Zhang, Wei Kim, Taejoon Leung, Shu-Hung City Univ Hong Kong Dept Elect Engn Hong Kong Peoples R China Univ Kansas Dept Elect Engn & Comp Sci Lawrence KS 66045 USA City Univ Hong Kong Dept Elect Engn State Key Lab Terahertz & Millimeter Waves Hong Kong Peoples R China

Data transmission over the millimeter wave (mmWave) in fifth-generation wireless networks aims to support very high speed wireless communications. A substantial increase in spectrum efficiency for mmWave transmission can be achieved by using advanced hybrid analog-digital precoding, for which accurate channel state information (CSI) is the key. Rather than estimating the entire channel matrix, it is now well-understood that directly estimating subspace information, which contains fewer parameters, does have enough information to design transceivers. However, the large channel use overhead and associated computational complexity in the existing channel subspace estimation techniques are major obstacles to deploy the subspace approach for channel estimation. In this paper, we propose a sequential two-stage subspace estimation method that can resolve the overhead issues and provide accurate subspace information. Utilizing a sequential method enables us to avoid manipulating the entire high-dimensional training signal, which greatly reduces the computational complexity. Specifically, in the first stage, the proposed method samples the columns of channel matrix to estimate its column subspace. Then, based on the obtained column subspace, it optimizes the training signals to estimate the row subspace. For a channel with N-r receive antennas and N-t transmit antennas, our analysis shows that the proposed technique only requires O(N-t) channel uses, while providing a guarantee of subspace estimation accuracy. By theoretical analysis, it is shown that the similarity between the estimated subspace and the true subspace is linearly related to the signal-to-noise ratio (SNR), i.e., O(SNR), at high SNR, while quadratically related to the SNR, i.e., O(SNR2), at low SNR. Simulation results show that the proposed sequential subspace method can provide improved subspace accuracy, normalized mean squared error, and spectrum efficiency over existing methods.

关键词： Channel estimation compressed sensing millimeter wave communication multi-input multi-output subspace estimation

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multi-Pair MIMO Two-Way Relaying: A Principal-Angle Perspective

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IEEE TRANSACTIONS ON SIGNAL PROCESSING 2016年第2期64卷 380-394页

作者： Xin, Haiyang Yuan, Xiaojun Liew, Soung-Chang Chinese Univ Hong Kong Dept Informat Engn Hong Kong Hong Kong Peoples R China ShanghaiTech Univ Sch Informat Sci & Technol Shanghai 200031 Peoples R China

This paper studies and analyzes a multi-pair MIMO two-way relay (TWR) system from a principal-angle perspective. In this system, users are grouped into pairs and two users in each pair exchange information through a common relay. The transmission scheme consists of two phases. In the uplink phase, the relay's receive signal space is divided into two subspaces for each pair: in one subspace, the signals of the two users are near-parallel, and physical-layer network coding (PNC) decoding is applied to retrieve network-coded messages;in the other subspace, the two user signals are near-orthogonal, and complete decoding (CD) is applied to retrieve individual user messages. In the downlink phase, the relay's transmit signal space is split into orthogonal subspaces for each pair, and in each subspace a common message is broadcasted to the two users. Our main contribution is to establish a critical link between the transmission scheme and the concept of principal angle in linear algebra. In particular, principal angle quantizes the degree of orthogonality between the user signals and helps determining how to partition the relay's receive signal space into PNC decoding subspace and CD decoding subspace. Building on that, we discuss the optimal design of user/relay precoders for both uplink and downlink phases to maximize the asymptotic sum-rate of the proposed scheme at high signal-to-noise ratio (SNR). The analysis and numerical results indicate that our scheme performs close to the cut-set outer bound and significantly outperforms the existing schemes in the literature.

关键词： multi-input multi-output physical-layer network coding principal angles/vectors two-way relay channel

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On the Performance of MIMO Full-Duplex Relaying System With SWIPT Under Outdated CSI

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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2020年第12期69卷 15580-15593页

作者： Hoang, Tran Manh Tran, Xuan Nam Nguyen, Ba Cao Dung, Le The Telecommun Univ Nha Trang 650000 Khanh Hoa Provi Vietnam Le Quy Don Tech Univ Adv Wireless Commun Grp Ha Noi City 100000 Vietnam Le Quy Don Tech Univ Fac Radio Elect Ha Noi City 100000 Vietnam Ton Duc Thang Univ Inst Computat Sci Div Computat Phys Ho Chi Minh City 700000 Vietnam Ton Duc Thang Univ Fac Elect & Elect Engn Ho Chi Minh City 700000 Vietnam

In this paper, we propose a full-duplex (FD) relaying system with multi-input multi-output (MIMO) with simultaneous wireless information and power transfer (SWIPT), where the communication from source to destination is assisted by a full-duplex decode-and-forward (DF) relay. The time switching (TS) protocol is used at the relay to harvest the energy of radio-frequency (RF) signals transmitted from the source. To improve both system performance and the amount of harvested energy, multiple antennas are used at source and destination. Transmit antenna selection (TAS) is employed at the source with an assumption that the feedback of channel state information (CSI) is outdated. Meanwhile, both selection combining (SC) and maximal ratio combining (MRC) techniques are applied at the destination. The closed-form expressions of the outage probability (OP), optimal throughput, and symbol error probability (SEP) are derived subject to the outdated CSI over Rayleigh fading channels. We also make a comparison between the performance of the proposed MIMO-FD relaying system with SWIPT and that of MIMO half-duplex (HD) relaying systems with and without SWIPT. The validity of derived mathematical expressions is verified by Monte-Carlo simulations. Numerical results show that the TAS/MRC scheme gives better system performance than the TAS/SC scheme. Moreover, higher energy harvesting time is needed to maximize the throughput than to minimize the OP.

关键词： multi-input multi-output full-duplex wireless power transfer decode-and-forward outage probability symbol error probability throughput

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On transforming hybrid nonlinear control problems with model uncertainty and input disturbance to mixed integer-linear programs

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JOURNAL OF THE FRANKLIN INSTITUTE-ENGINEERING AND APPLIED MATHEMATICS 2023年第18期360卷 14406-14415页

作者： Merrikh-Bayat, Farshad Mirhoseini, Parvin Univ Scranton Phys & Engn Dept Scranton PA 18510 USA Univ Zanjan Dept Elect & Comp Engn Zanjan Iran

Control of multi-input multi-output (MIMO) hybrid nonlinear dynamic systems which are affine in control inputs is studied in this paper. It is assumed that each control input of the system can be continuous or discrete with a bound constraint. It is also assumed that the controller is discrete-time and updates the control(s) with a constant frequency. Based on these assumptions, a theorem which represents the necessary and sufficient condition for uniform convergence of the sequence of samples of the state vector of system towards the desired point is presented and proved. As a result of this theorem, a (mixed integer-) linear programming for calculation of control(s) is proposed. Two well-known nonlinear hybrid control problems with multiple inputs are solved by using the proposed method and the results are presented.

关键词： Hybrid control input-affine hybrid nonlinear system Linear programming Mixed integer-linear programming multi-input multi-output

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REAL-TIME IMPLEMENTATION OF A MIMO ADAPTIVE POWER-SYSTEM STABILIZER

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IEE PROCEEDINGS-C GENERATION TRANSMISSION AND DISTRIBUTION 1990年第3期137卷 186-194页

作者： PAHALAWATHA, NC HOPE, GS MALIK, OP WONG, K Department of Electrical Engineering University of Calgary Calgary Canada

Power systems are non-linear and they are often subjected to random disturbances. Therefore stochastic controllers with on-line system identification are ideally suited to power system control problems. Experience with a real time implementation of an adaptive power system stabiliser to damp the dynamic oscillations of a power system is presented. A multi-input multi-output (MIMO) pole shifting control algorithm together with a least-square system identification is used. The system identification is improved using a variable forgetting factor in the recursive least-squares algorithm. The computation time was greatly reduced by streamlining the identification algorithm using the sparse nature of the matrices associated with the computation and by using parallel processing techniques. The controller was tested in real time using a physical model of a power system. The results show that the damping of the power system dynamic oscillations can be improved by using this controller.

关键词： random disturbances Power engineering computing dynamic oscillations parallel processing parallel processing techniques recursive least-squares algorithm power system computer control Control of electric power systems Self-adjusting control systems MIMO adaptive power system stabiliser online system identification Power system management, operation and economics stability variable forgetting factor Control engineering computing damping pole shifting control algorithm stochastic controllers real-time multi-input multi-output Stability in control theory adaptive control

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Predictive functional control based on particle swarm optimisation algorithm for MIMO process with time delay

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INTERNATIONAL JOURNAL OF MODELLING IDENTIFICATION AND CONTROL 2021年第1期39卷 29-38页

作者： Ghadiri, Hamid Khodadadi, Hamed Razavi, S. Ehsan Islamic Azad Univ Qazvin Branch Fac Elect Biomed & Mech Engn Qazvin Iran Islamic Azad Univ Khomeinishahr Branch Dept Elect Engn Esfahan Iran Islamic Azad Univ Dept Elect Engn Mashhad Branch Mashhad Razavi Khorasan Iran

The present study aims to propose a method for designing a predictive functional control (PFC) based on the particle swarm optimisation (PSO) algorithm for the multi-input multi-output (MIMO) process with time delay. Due to the cross-coupling, time delay, and other MIMO industrial process challenges, the classical controller could not overcome the system challenges. PFC is a model-based predictive controller that uses the state-space equations of the system. According to the results, the optimisation problem is resolved using the PSO for determining the optimal controller parameters. The incorporated PFC and PSO's performance as the proposed controller is evaluated using simulations on the chamber pressure coke furnace as a MIMO process with time-delay. The simulation results demonstrate that the PFC variables tuned by the PSO approach have better performance compared to the conventional PFC, especially in the presence of disturbances and uncertainty.

关键词： multi-input multi-output MIMO time delay predictive functional control PFC particle swarm optimisation PSO chamber pressure

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STATE-SPACE MODEL IDENTIFICATION USING input AND output DATA WITH STEADY STATE VALUES

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CONTROL AND INTELLIGENT SYSTEMS 2008年第3期36卷 201-207页

作者： Kosaka, M. Uda, H. Department of Mechanical Engineering Faculty of Science and Engineering Kinki University Higashiosaka Osaka 577-8502 3-4-1 Kowakae Japan

In this paper, we propose a new deterministic off-line identification method that obtains a state-space model by using input and output data with steady state values. This method is composed of the method, M. Kosaka, K. Koizumi and H. Shibata Transactions of the Society of Instrument and Control Engineers 36(4), 2000, 319-327. zeroing the 0 similar to N-tuple integral values of output error of single-input single-output transfer function model and Ho-Kalman's method, H.P. Zeiger and A.J. Mc Ewen, IEEE Transactions on Automatic Control, AC 19-2, 1974, 153. The feature is that this method can identify by using step responses and, consequently, this is suitable for mechanical system identification in which noise and vibration are undesirable. Numerical simulations of multi-input multi-output system identification and experimental results are illustrated.

关键词： Identification state space model step response multi-input multi-output mechanical system

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Data Rate Quadrupled Coherent Microwave Photonic Link

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IEEE PHOTONICS TECHNOLOGY LETTERS 2017年第13期29卷 1071-1074页

作者： Chen, Xiang Yao, Jianping Univ Ottawa Sch Elect Engn & Comp Sci Microwave Photon Res Lab Ottawa ON K1N 6N5 Canada

A data rate quadrupled microwave photonic link (MPL) based on coherent detection and digital signal processing (DSP) is proposed and experimentally demonstrated. The data rate is quadrupled by employing both intensity and phase modulation and polarization multiplexing to transmit four microwave vector signals with an identical microwave center frequency over a single optical carrier. The recovery of the four microwave signals is implemented at a coherent receiver followed by DSP with a new algorithm, to separate the four microwave vector signals and to eliminate the phase noise from the transmitter and local oscillator laser sources and to cancel the unstable frequency offset between the two laser sources. Error-free transmission of four 2.5-Gpbs 16-QAM microwave vector signals with a total data rate of 10 Gbps if forward error correction (FEC) is employed. The total net data rate is 9.225 Gbps if the zero padding and the FEC (overhead 6.7%) are considered. The use of the proposed MPL for the implementation of 4 x 4 MIMO is also discussed.

关键词： Digital signal processing (DSP) laser phase noise microwave photonic link multi-input multi-output optical coherent detection phase noise cancellation (PNC)

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