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Chinese Journal of Chemical Engineering 2023年第5期57卷 247-264页

作者： Kejin Huang Shuaishuai Han Lijing Zang Haisheng Chen Yihang Luo Liang Zhang Yang Yuan Xing Qian Shaofeng Wang college of information science and technology Beijing University of Chemical TechnologyBeijing 100029China

For dividing-wall distillation columns(DWDCs) separating a heavy-component dominated and wide boiling-point ternary(HCDWBT) mixture, a significant amount of excessive heat exists inevitably in stripping the heavy-component from the intermediate-component and it can be employed to initiate the development of vapor recompression heat pump(VRHP) assisted DWDC(VRHP-DWDC). Despite dividing wall may locate in the top, middle, and bottom, the optimum VRHP-DWDC is found to involve uniformlytwo VRHP circles. While the first one serves to compress and transform the excessive heat resulted from the separation of the heavy-component from the intermediate-component, the second one to compress and transform the overhead vapor stream of the light-component pre-heated sequentially with the condensate from the first one and the bottom product stream of the heavy-component, both releasing the temperature-elevated latent heat to the pre-fractionator's or common stripping section. The processing of two HCDWBT mixtures of benzene/toluene/o-xylene and n-pentane/n-hexane/n-heptane are selected to assess the derived optimum topological configurations of the VRHP-DWDC and their optimality is confirmed through detailed comparisons with the DWDC and two VRHP-DWDCs involving only one VRHP circle. The proposed strategy helps to tap the full potential of the VRHP-DWDC with considerably alleviated complication in process development.

关键词： dividing-wall distillation columns Heavy-component dominance Vapor recompression heat pump Process development Economic behavior

Reinforced temperature control of a reactive double dividing-wall distillation column

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Chinese Journal of Chemical Engineering 2023年第2期54卷 288-295页

作者： Wei Qin Lijing Zang Kejin Huang Haisheng Chen Yang Yuan Xing Qian Liang Zhang Shaofeng Wang college of information science and technology Beijing University of Chemical TechnologyBeijing 100029China

The mass and thermal coupling makes the control of the reactive double dividing-wall distillation column(R-DDWDC) an especially challenging issue with a highly interactive nature. With reference to the separation of an ideal endothermic quaternary reversible reaction with the most unfavorable ranking of relative volatilities(A + B ■ C + D with α_(A)>α_(C)>α_(D)>α_(B)), the operation rationality of the R-DDWDC is studied in this contribution. The four-point single temperature control system leads to great steady-state discrepancies in the compositions of products C and D and the reason stems essentially from the failure in keeping strictly the stoichiometric ratio between reactants A and B. A temperature plus temperature cascade control scheme is then employed to reinforce the stoichiometric ratio control and helps to secure a substantial abatement in the steady-state discrepancies. A temperature difference plus temperature cascade control scheme is finally synthesized and leads even to better performance than the most effective double temperature difference control scheme. These outcomes reveal not only the operation feasibility of the R-DDWDC but also the general significance of the proposed temperature difference plus temperature cascade control scheme to the inferential control of any other complicated distillation columns.

关键词： Reactive double dividing-wall distillation column Temperature control Temperature plus temperature cascade control Temperature difference plus temperature cascade control Process operation

Accountable attribute-based authentication with fine-grained access control and its application to crowdsourcing

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Frontiers of Computer science 2023年第1期17卷 205-218页

作者： Peng LI Junzuo LAI Yongdong WU college of information science and technology Jinan UniversityGuangzhou 510632China

We introduce a new notion called accountable attribute-based authentication with fine-grained access control (AccABA), which achieves (i) fine-grained access control that prevents ineligible users from authenticating;(ii) anonymity such that no one can recognize the identity of a user;(iii) public accountability, i.e., as long as a user authenticates two different messages, the corresponding authentications will be easily identified and linked, and anyone can reveal the user’s identity without any help from a trusted third party. Then, we formalize the security requirements in terms of unforgeability, anonymity, linkability and traceability, and give a generic construction to fulfill these requirements. Based on AccABA, we further present the first attribute-based, fair, anonymous and publicly traceable crowdsourcing scheme on blockchain, which is designed to filter qualified workers to participate in tasks, and ensures the fairness of the competition between workers, and finally balances the tension between anonymity and accountability.

关键词： fine-grained access control anonymous authentication accountability fairness crowdsourcing blockchain

A Fairness-Enhanced Intelligent MAC Scheme Using Q-Learning-Based Bidirectional Backoff for Distributed Vehicular Communication Networks

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Tsinghua science and technology 2023年第2期28卷 258-268页

作者： Ping Wang Shuai Wang college of information science and technology Donghua UniversityShanghai 201620China

With the increasing attention to front-edge vehicular communication applications,distributed resource allocation is beneficial to the direct communications between vehicle nodes.However,in highly dynamic distributed vehicular networks,quality of service(QoS)of the systems would degrade dramatically because of serious packet collisions in the absence of sufficient link knowledge.Focusing on the fairness optimization,a Q-learning-based collision avoidance(QCA)scheme,which is characterized by an ingenious bidirectional backoff reward model RQCA corresponding to arbitrary backoff stage transitions,has been proposed in an intelligent distributed media access control protocol.In QCA,an intelligent bidirectional backoff agent based on the Markov decision process model can actively motivate each vehicle agent to update itself toward an optimal backoff sub-intervel BSIopt through either positive or negative bidirectional transition individually,resulting in the distinct fair communication with a proper balance of the resource allocation.According to the reinforcement learning theory,the problem of goodness evaluation on the backoff stage self-selection policy is equal to the problem of maximizing Q function of the vehicle in the current environment.The final decision on BSI_(opt) related to an optimal contention window range was solved through maximizing the Q value or Q_(max).The ε-greedy algorithm was used to keep a reasonable convergence of the Q_(max) solution.For the fairness evaluation of QCA,four kinds of dynamic impacts on the vehicular networks were investigated:mobility,density,payload size,and data rate with a network simulator NS2.Consequently,QCA can achieve fair communication efficiently and robustly,with advantages of superior Jain’s fairness index,relatively high packet delivery ratio,and low time delay.

关键词： media access control(MAC) fairness Q-learning-based collision avoidance(QCA) bidirectional backoff agent vehicular communication networks

Splitting and placement of data-intensive applications with machine learning for power system in cloud computing

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Digital Communications and Networks 2022年第4期8卷 476-484页

作者： Zhanyang Xu Dawei Zhu Jinhui Chen Baohua Yu School of Computer and Software Nanjing University of Information Science and TechnologyNanjingChina college of information science and technology Shihezi UniversityXinjiangChina

Aiming to meet the growing demand for observation and analysis in power systems that based on Internet of Things(IoT),machine learning technology has been adopted to deal with the data-intensive power electronics applications in IoT.By feeding previous power electronic data into the learning model,accurate information is drawn,and the quality of IoT-based power services is improved.Generally,the data-intensive electronic applications with machine learning are split into numerous data/control constrained tasks by workflow technology.The efficient execution of this data-intensive Power Workflow(PW)needs massive computing resources,which are available in the cloud infrastructure.Nevertheless,the execution efficiency of PW decreases due to inappropriate sub-task and data placement.In addition,the power consumption explodes due to massive data acquisition.To address these challenges,a PW placement method named PWP is devised.Specifically,the Non-dominated Sorting Differential Evolution(NSDE)is used to generate placement strategies.The simulation experiments show that PWP achieves the best trade-off among data acquisition time,power consumption,load distribution and privacy preservation,confirming that PWP is effective for the placement problem.

关键词： IoT-based power system Cloud Workflow Machine learning NSDE

Traveling chimera states in locally coupled memristive Hindmarsh-Rose neuronal networks and circuit simulation

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science China(Technological sciences) 2022年第7期65卷 1445-1455页

作者： YUAN YuanYuan YANG Hao HAN Fang WANG ZhiJie college of information science and technology Donghua UniversityShanghai 201620China

Chimera states have been found in many physiology systems as well as nervous systems and may relate to neural information processing. The present work investigates the traveling chimera states in memristive neuronal networks of locally coupled Hindmarsh-Rose neurons, with both excitation and inhibition considered. Various traveling chimera patterns and firing modes are found to exist in the networks. Particularly, for excitatory connection, two kinds of traveling chimera states appear in opposite directions. Besides, a new type of chimera state composed of traveling chimera state and incoherent state is observed, named the semi-traveling chimera state. Multi-head traveling chimera states with several incoherent groups are also observed. For excitatory-inhibitory connection, the network is observed to exhibit an imperfect coherent state under the synergistic effect of strong excitatory and weak inhibitory coupling. Moreover, a firing pattern named mixed-amplitude bursting state is witnessed,consisting of two bursts of different amplitudes in a time sequence. Furthermore, an electric circuit is designed and built on Multisim to realize the above phenomena, suggesting that traveling chimera states could be generated in real circuits. Our findings can deepen the understanding of the electromagnetic induction effect in regulating the dynamics of neuronal networks and may provide useful clues for constructing artificial neural systems.

关键词： memristive neuronal network traveling chimera state firing pattern electric circuit

Distributed Secure State Estimation of Multi-Agent Systems Under Homologous Sensor Attacks

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IEEE/CAA Journal of Automatica Sinica 2023年第1期10卷 67-77页

作者： Yukun Shi Youqing Wang Jianyong Tuo the college of information science and technology Beijing University of Chemical TechnologyBeijing 100029China IEEE

This paper addresses the problem of distributed secure state estimation for multi-agent systems under homologous sensor attacks.Two types of secure Luenberger-like distributed observers are proposed to estimate the system state and attack signal simultaneously.Specifically,the proposed two observers are applicable to deal with the cases in the presence and absence of time delays during network communication.It is also shown that the proposed observers can ensure the attack estimations from different agents asymptotically converge to the same value.Sufficient conditions for guaranteeing the asymptotic convergence of the estimation errors are derived.Simulation examples are finally provided to demonstrate the effectiveness of the proposed results.

关键词： Consensus-based Luenberger-like observer distributed secure state estimation homologous signal

Coordinated underwater dark channel prior for artifact removal of challenging image enhancement

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光电子快报:英文版 2023年第7期19卷 416-424页

作者： ZHANG Jiaokuan LIU Hao YING Xiaoqing HUANG Rong college of information science and technology Donghua UniversityShanghai 201620China

When dehazing underwater images,the patch-by-patch dark channel prior(DCP) method is frequently used.After the DCP-based processing,there are still some drawbacks,such as patch artifacts,and these artifacts will seriously affect the subjective quality of some challenging images.To remove the patch artifacts from the DCP-guided enhancement mechanism,this paper proposes a coordinated underwater dark channel prior(CUDCP) method.The proposed method considers the characteristics of the red-green-blue channels with different attenuation situations,and thus the attenuation ratios of the red-green-blue channels are adaptively coordinated in diverse images.The requirement for color restoration is then assessed by an evaluation criterion,and the color restoration is carried out by using the compensated gray world(CGW) theory,which further coordinates the intensity of various red-green-blue channels.Our method next applies a patch-division average filter in accordance with the sub-patch classification.On the typical dataset,the enhanced images of our CUDCP method have higher average underwater image quality measure(UIQM) scores(about 2.274 8) when compared with the original images and those of some state-of-the-art enhancement methods,while the computational cost of CUDCP(about 88.618 8 s) is slightly higher than that of the original DCP(about 87.493 8 s).The experimental results demonstrate that in comparison to state-of-the-art enhancement methods,the proposed method can significantly reduce patch artifacts in challenging image enhancement,while maintaining the objective quality of such underwater images,and also enhancing their subjective quality at a reasonable computational cost.

关键词： underwater patch image

Reconfigurable Intelligent Surface-Based Hybrid Phase and Code Modulation for Symbiotic Radio

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中国通信:英文版 2023年第10期20卷 30-42页

作者： Song Bai Qiang Li Donghong Cai college of information science and technology Jinan UniversityGuangzhou 510632China

Reconfigurable intelligent surface(RIS)-assisted symbiotic radio is a spectrum-and energy-efficient communication paradigm,in which an RIS performs passive beamforming to enhance active transmission,while using the electromagnetic waves from the active transmission for additional information transfer(i.e.,passive transmission).In this paper,a hybrid RIS-based modulation,termed hybrid phase and code modulation(HPCM),is proposed to improve the reliability of RIS-assisted symbiotic radio.In RIS-HPCM,the RIS simultaneously performs direct sequence spread spectrum and passive beamforming on incident signals.Moreover,both the spreading code and phase offset are exploited to carry the RIS’s own information.A low-complexity detector is designed,in which the receiver first detects the spreading codes and then demodulates the constellation symbols.We analyze the bit error rate(BER)performance of RIS-HPCM over Rician fading channels.BER upper bounds and approximate BER expressions are derived in closed-form for maximum-likelihood and low-complexity detectors,respectively.Simulation results in terms of BER verify the analysis and show the superiority of RIS-HPCM over the existing RIS-based modulation.

关键词： reconfigurable intelligent surface symbiotic radio index modulation direct sequence spread spectrum performance analysis

A Novel Energy and Communication Aware Scheduling on Green Cloud Computing

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Computers, Materials & Continua 2023年第12期77卷 2791-2811页

作者： Laila Almutairi Shabnam Mohamed Aslam Department of Computer Engineering Computer Science and Information Technology CollegeMajmaah UniversityAl Majmaah11952Saudi Arabia Department of information technology Computer Science and Information Technology CollegeMajmaah UniversityAl Majmaah11952Saudi Arabia

The rapid growth of service-oriented and cloud computing has created large-scale data centres worldwide.Modern data centres’operating costs mostly come from back-end cloud infrastructure and energy consumption.In cloud computing,extensive communication resources are required.Moreover,cloud applications require more bandwidth to transfer large amounts of data to satisfy end-user requirements.It is also essential that no communication source can cause congestion or bag loss owing to unnecessary switching buffers.This paper proposes a novel Energy and Communication(EC)aware scheduling(EC-scheduler)algorithm for green cloud computing,which optimizes data centre energy consumption and traffic load.The primary goal of the proposed EC-scheduler is to assign user applications to cloud data centre resources with minimal utilization of data centres.We first introduce a Multi-Objective Leader Salp Swarm(MLSS)algorithm for task sorting,which ensures traffic load balancing,and then an Emotional Artificial Neural Network(EANN)for efficient resource allocation.EC-scheduler schedules cloud user requirements to the cloud server by optimizing both energy and communication delay,which supports the lower emission of carbon dioxide by the cloud server system,enabling a green,unalloyed environment.We tested the proposed plan and existing cloud scheduling methods using the GreenCloud simulator to analyze the efficiency of optimizing data centre energy and other scheduler metrics.The EC-scheduler parameters Power Usage Effectiveness(PUE),Data Centre Energy Productivity(DCEP),Throughput,Average Execution Time(AET),Energy Consumption,and Makespan showed up to 26.738%,37.59%,50%,4.34%,34.2%,and 33.54%higher efficiency,respectively,than existing state of the art schedulers concerning number of user applications and number of user requests.

关键词： EC-scheduler green cloud energy efficiency task scheduling task sorting resource allocation