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A model predictive control strategy with switching cost functions for cooperative operation of trains

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Science China(Information Sciences) 2023年第7期66卷 224-236页

作者： Zixuan ZHANG Haifeng SONG Hongwei WANG Ling LIU Hairong DONG State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University School of Electronic and Information Engineering Beihang University Beijing National Railway research and Design institute of signal and communication

The cooperative control of trains is proposed as an innovative method for further improving operation efficiency. Model predictive control(MPC) has been widely discussed for multiple trains because it can handle the challenges posed by the cooperative control problem, such as complex constraints. In real situations, multiple objectives, such as comfort and safety, must be considered when controlling multiple trains with MPC, and the total objective may change during operation, affecting control performance. In this paper, a distributed structure based on switching cost function model predictive control(ScMPC) for multiple trains in a switching situation is given, where the cost functions of the train control problem change with the variable demand of cooperative operation. Furthermore, the feasibility of the proposed method and stability of the closed-loop system are proved to guarantee the stable operation of the controlled ***, the control method’s effectiveness is verified. Three kinds of cost functions are given, and their control performance is compared to show the effect of different weights and the advantage of ScMPC.

关键词： cooperative control switching cost functions model predictive control automatic train operation railway train

Design and implementation of scenic-spot introduction-task-oriented3D virtual human spoken dialogue system

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Journal of Beijing institute of Technology 2014年第3期23卷 395-400页

作者：吴王惠谢湘焦祎姗张征高高 research institute of communication Technology Beijing Institute of Technology

A scenic-spot introduction-task-oriented 3D virtual human spoken dialogue system-- EasyGuide is introduced. The system includes five modules： natural language processing, task do- main knowledge database, dialogue management, voice processing and 3D virtual human text-to-vis- ual speech synthesis. In the first module, dictionary construction along with sentence analysis and semantic representation axe illustrated specifically. A tree-structured knowledge database is designed for the task domain. A novel framework based on the keyword analysis and context constraints is proposed as the dialogue management. As for voice processing module, a software development kit which performs speech recognition and synthesis is introduced briefly. In the last module, 3D viseme synthesis is explained with examples and a text-driven facial animation system is presented. Evalua- tion results show that the system can achieve satisfactory performance.

关键词： spoken dialogue system speech recognition dialogue management.

Gamma oscillations and their role in orchestrating balance and communication following stroke

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Neural Regeneration research 2025年第2期20卷 477-478页

作者： Montana Samantzis Cong Wang Matilde Balbi Queensland Brain institute The University of QueenslandBrisbaneQLDAustralia Engineering research Centre of Traditional Chinese Medicine Intelligent Rehabilitation Ministry of EducationShanghaiChina

Induced brain oscillations in the gamma range have recently garnered attention due to their reported neuroprotective effects in the treatment of Alzheimer’s *** method differs from pharmacological approaches by tapping into the neuronal population dynamics that underlie the homeostatic processes in the brain that are crucial for the recovery of ***,induced gamma-range oscillations have been used to improve cerebral blood flow,motor function,and synaptic plasticity in a mouse model of focal stroke,highlighting the broad potential of recruiting intrinsic recovery processes for the treatment of neurological *** open questions,such as the frequency specificity of the benefits,will shed light on the intrinsic processes involved and allow clinicians to optimize recovery after stroke.

关键词： protective specificity Alzheimer

Resource allocation based on subcarrier exchange in multiuser OFDM system

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Science China(Information Sciences) 2013年第1期56卷 184-197页

作者： WANG Ye ZHANG QinYu ZHANG NaiTong Harbin institute of Technology Shenzhen Graduate School Communication Engineering Research Center Harbin institute of Technology Communication Research Center

Multi-user orthogonal frequency division multiplexing(OFDM) is one of the most important techniques for next-generation wireless communication *** sum capacity and proportional fairness index are two important metrics in OFDM adaptive resource *** existing researches,the two metrics have individually yielded approximately optimal ***,as the two goals seem to contradict each other,it means that they cannot achieve optima *** paper presents a resource allocation algorithm based on subcarrier *** relaxing the fairness index,the proposed algorithm can dynamically adjust the fairness ***,By considering a criterion that minimizes the loss of sum capacity,the proposed algorithm can balance the tradeoff between fairness and sum *** contrast to existing algorithms,our proposal improves performance by approximately 30% in terms of sum capacity,at the expense of approximately 10% reduction in proportional ***,if a malicious user exists,each user in the system can obtain higher ergodic capacity compared with the conventional *** decrease the complexity,a low-complexity simplified alternative is presented,which outperforms the conventional algorithm with an increase in the number of *** numerical simulations are carried out to verify the efficiency and ***,we discuss in detail the computational complexity of the proposed algorithm.

关键词： multiuser OFDM resource allocation capacity proportional fairness computational complexity

Performance analysis of hybrid carrier DS CDMA communication system

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Journal of Harbin institute of Technology(New Series) 2012年第4期19卷 77-82页

作者：邱昕沙学军梅林 communication research Center Harbin Institute of Technology

A hybrid carrier (HC) DS CDMA communication system is proposed, combining 4-weighted fractional Fourier transform (4-WFRFT) with code division multiple access (CDMA) technique. The signals are modulated in a certain order fractional Fourier domain and transformed by 4-WFRFT to compose the hybrid carrier signals. In the time domain CDMA technique is adopted for multiple accesses and time diversity gain. Compared to orthogonal frequency division multiplexing (OFDM) system, in which Fourier transform is adopted, the signal energy in HC system is distributed on the time-frequency plane more evenly and symmetrically. Thus, when there is a deep fading notch or single-frequency interference in the channel, the proposed method can split the interference to a broader range in order to reduce the influence, resulting in the better system performance. Moreover, the performances of the proposed system, such as peak-to-average power rate (PAPR) and security are also discussed in the paper.

关键词： 4-weighted fractional Fourier transform code division multiple access carrier scheme selective channel

Spatially localized and joint access point selection for Wi-Fi indoor positioning

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Journal of Harbin institute of Technology(New Series) 2012年第6期19卷 27-33页

作者：邓志安马琳徐玉滨 communication research Center Harbin Institute of Technology

Wi-Fi indoor positioning system has received increasing interest in pervasive computing applications due to its low cost and satisfactory accuracy. To obtain high positioning accuracy based on source limited devices, various AP selection strategies have been proposed to select the most discriminant APs for positioning. In this paper, we propose a spatially localized AP selection method based on joint location information gain. In contrast to traditional AP selection methods which measure the discriminant ability of APs independently, we consider choosing APs jointly. By considering the correlation of the discriminant ability between different APs, more accurate measure of the discriminant ability of APs can be taken. Furthermore, since the optimal AP selection solution varies spatially, we incorporate a location clustering method to localize AP selection and subsequent positioning process. Finally, support vector regression (SVR) algorithm is combined to estimate the location. Experiments are carried in a realistic Wi-Fi indoor environment. Experimental results show that, by using the localized joint AP selection strategy, the proposed positioning method achieves a high-level accuracy while reducing the energy consumption on client devices significantly.

关键词： Wi-Fi AP selection clustering analysis support vector regression indoor positioning

A Re-Configurable Dual-Mode Delay-Aware Scheduling and Resource Allocation for LTE System

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Journal of Harbin institute of Technology(New Series) 2015年第1期22卷 99-105页

作者： Hongtao Yu Zhongzhao Zhang Zhuoming Li communication research Center Harbin Institute of Technology

Long Term Evolution( LTE) has been proposed as an advanced wireless radio access technology to provide higher peak data rates and better spectral utilization efficiency,but the classical scheduling and resource allocation algorithms cannot optimally enhance the system performance due to high computational complexity. In this paper,a re-configurable dual mode delay-aware( CDD) scheduling and resource allocation algorithm is proposed to achieve the joint consideration of scheduling pattern,scheduling priority and quantity of scheduled data. In this study,dual-mode scheduling mechanism is associated with three configurable parameters and the CDD algorithm is involved to guarantee queuing delay with low loss of resource utilization and *** computational cost of the scheduling and resource allocation algorithm is significantly reduced by efficiently utilizing Qo S Class Identifier( QCI) and Channel Quality Indicator( CQI) defined by LTE standards. The simulation results based on different application scenarios also represent the computation cost and complexity of scheduling algorithm along with the improved system throughput.

关键词： CQI LTE QCI resource allocation scheduling

Realization of finite precision chaotic systems via internal perturbation

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High Technology Letters 2013年第4期19卷 346-352页

作者：李德志 Wang Zhenyong Gu Xuemai Guo Qing communication research Center Harbin Institute of Technology

A method of controllable internal perturbation inside the chaotic map is proposed to solve the problem in chaotic systems caused by finite precision.A chaotic system can produce large amounts of initial-sensitive,non-cyclical pseudo-random ***,the finite precision brings short period and odd points which obstruct application of chaos theory seriously in digital communication *** in chaotic systems is a possible efficient method for solving finite precision problems,but former researches are limited in uniform distribution *** proposed internal perturbation can work on both uniform and non-uniform distribution chaotic maps like Chebyshev map and Logistic *** simulations,results show that the proposed internal perturbation extends sequence periods and eliminates the odd points,so as to improve chaotic performances of perturbed chaotic sequences.

关键词： finite precision internal perturbation chaotic system

research on cooperative detection and multiple access for cognitive radio system

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Journal of Harbin institute of Technology(New Series) 2011年第6期18卷 86-92页

作者： Anna Auguste Anghuwo 刘鑫谭学治 communication research Center Harbin Institute of Technology

As cognitive radio (CR) needs to detect spectrum accurately and utilize the idle spectrum efficiently,a new model of CR is *** model adopts energy detection with auto-adapted threshold and produces spectrum mark *** basis function is obtained through making IDFT to the inner product of spectrum and phase vectors,and it is variable with the spectrum *** are sent through modulation on the basis function,and it can be estimated by correlation in the receiving *** cooperative detection and multiple access of this model are also researched in this paper,and the performance is finally *** show the cooperative detection of this model can obtain higher detection probability,and the disaccord of the basis functions between sending and receiving ends can lower its performance.

关键词： cognitive radio energy detection basis function