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Exergy and exergoeconomic analyses for integration of aromatics separation with aromatics upgrading

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Frontiers of Chemical Science and Engineering 2023年第2期17卷 183-193页

作者： Dan Zhang Minbo Yang XIAO Feng Shaanxi Key Laboratory of Energy Chemical Process Intensification School of Chemical Engineering&TechnologyXi’an Jiaotong UniversityXi’an 710049China

Methanol to aromatics produces multiple products,resulting in a limited selectivity of xylene.Aromatics upgrading is an effective way to produce more valuable xylene product,and different feed ratios generate discrepant product distributions.This work integrates the aromatics separation with toluene disproportionation,transalkylation of toluene and trimethylbenzene,and isomerization of xylene and trimethylbenzene.Exergy and exergoeconomic analyses are conducted to give insights in the splitting ratios of benzene,toluene and heavy aromatics for aromatics upgrading.First,a detailed simulation model is developed in Aspen HYSYS.Then,300 splitting ratio sets of benzene and toluene for conversion are studied to investigate the process performances.The results indicate that there are different preferences for the splitting ratios of benzene and toluene in terms of exergy and exergoeconomic performances.The process generates lower total exergy destruction when the splitting ratio of toluene varies between 0.07 and 0.18,and that of benzene fluctuates between 0.55 and 0.6.Nevertheless,the process presents lower total product unit cost with the splitting ratio of toluene less than 0.18 and that of benzene fluctuating between 0.44 and 0.89.Besides,it is found that distillation is the biggest contributor to the total exergy destruction,accounting for 94.97%.

关键词： aromatics separation and upgrading variant splitting ratios total exergy destruction total product unit cost

Event-Triggered Control for Multi-Agent Systems:Event Mechanisms for Information Transmission and Controller Update

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Journal of Systems Science & Complexity 2022年第3期35卷 953-972页

作者： LIU Pin XIAO Feng WEI Bo State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China School of Control and Computer Engineering North China Electric Power UniversityBeijing 102206China

This paper investigates the state consensus of linear multi-agent systems in a graph where each agent is equipped with two novel event-triggering mechanisms.Each agent utilizes them to avoid continuous information transmissions with its neighbors and to reduce the frequencies of controller updates,respectively.One of the event-triggering mechanisms defines a threshold of state errors by a constant plus a state-dependent variable.The other event-triggering mechanism introduces a period of rest time after each event.For each agent,both event-triggering mechanisms are fully distributed and are independent of any global information.The authors utilize a co-design approach to deal with the interplay between control gains and parameters in event-triggering mechanisms.With appropriate control gains in control laws and parameters in event-triggering conditions,subsystems employing discrete-time signals from neighbors and discrete-time signals from their controllers achieve the state consensus.Simulations are performed to illustrate the effectiveness of the proposed event-triggering mechanisms.

关键词： Consensus control event-triggering mechanism multi-agent systems output feedback

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原晓风三焦辨治小儿过敏性紫癜临床经验

中国中医基础医学杂志 2021年第4期27卷 669-670,677页

作者：崔洪涛原晓风重庆市中医院重庆400021 重庆医科大学重庆400016 长春中医药大学长春130117 长春中医药大学附属医院长春130021

本文总结原晓风三焦辨证治疗小儿过敏性紫癜临床经验。阐述皮肤型过敏性紫癜可以上焦辨证,分为风热伤络证与血热妄行证,辨治重在调治上焦气血;腹型过敏性紫癜可从中焦辨治,分为外感湿热困脾证、阳明血热证和气不摄血证,辨治重在调治中... 详细信息

本文总结原晓风三焦辨证治疗小儿过敏性紫癜临床经验。阐述皮肤型过敏性紫癜可以上焦辨证,分为风热伤络证与血热妄行证,辨治重在调治上焦气血;腹型过敏性紫癜可从中焦辨治,分为外感湿热困脾证、阳明血热证和气不摄血证,辨治重在调治中焦脾胃气血;肾型过敏性紫癜及紫癜性肾炎等病症可从下焦辨治,主要有阴虚火旺证和肾阳不足证,以祛邪为标、扶正为本,辨治重在益髓填精保护肾脏。顾护脾胃之气与预防并及早治疗过敏性紫癜导致的肾损害,是三焦辨治小儿过敏性紫癜的核心所在,体现中医治未病学术思想。

关键词：三焦辨证小儿过敏性紫癜临床经验原晓风

Dynamic event-triggered formation control of second-order nonholonomic systems

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Journal of Systems Engineering and Electronics 2023年第2期34卷 501-514页

作者： WANG xiaoyu SUN Sijia XIAO Feng YU Mei School of Control and Computer Engineering North China Electric Power UniversityBeijing 102206China State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China

In this paper,the formation control problem of secondorder nonholonomic mobile robot systems is investigated in a dynamic event-triggered scheme.Event-triggered control protocols combined with persistent excitation(PE)conditions are presented.In event-detecting processes,an inactive time is introduced after each sampling instant,which can ensure a positive minimum sampling interval.To increase the flexibility of the event-triggered scheme,internal dynamic variables are included in event-triggering conditions.Moreover,the dynamic event-triggered scheme plays an important role in increasing the lengths of time intervals between any two consecutive events.In addition,event-triggered control protocols without forward and angular velocities are also presented based on approximate-differentiation(low-pass)filters.The asymptotic convergence results are given based on a nested Matrosov theorem and artificial sampling methods.

关键词： nonholonomic system dynamic event-triggered control consensus-based formation

Spatiotemporal distance embedded hybrid ant colony algorithm for a kind of vehicle routing problem with constraints

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Frontiers of Information Technology & Electronic Engineering 2023年第7期24卷 1062-1079页

作者： Zhenhui feng Renbin xiao School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China Institute of Artificial Intelligence Huazhong University of Science and TechnologyWuhan 430074China Key Laboratory of Image Information Processing and Intelligent Control Ministry of EducationWuhan 430074China

We investigate a kind of vehicle routing problem with constraints(VRPC)in the car-sharing mobility environment,where the problem is based on user orders,and each order has a reservation time limit and two location point transitions,origin and destination.It is a typical extended vehicle routing problem(VRP)with both time and space constraints.We consider the VRPC problem characteristics and establish a vehicle scheduling model to minimize operating costs and maximize user(or passenger)experience.To solve the scheduling model more accurately,a spatiotemporal distance representation function is defined based on the temporal and spatial properties of the customer,and a spatiotemporal distance embedded hybrid ant colony algorithm(HACA-ST)is proposed.The algorithm can be divided into two stages.First,through spatiotemporal clustering,the spatiotemporal distance between users is the main measure used to classify customers in categories,which helps provide heuristic information for problem solving.Second,an improved ant colony algorithm(ACO)is proposed to optimize the solution by combining a labor division strategy and the spatiotemporal distance function to obtain the final scheduling route.Computational analysis is carried out based on existing data sets and simulated urban instances.Compared with other heuristic algorithms,HACA-ST reduces the length of the shortest route by 2%–14%in benchmark instances.In VRPC testing instances,concerning the combined cost,HACA-ST has competitive cost compared to existing VRP-related algorithms.Finally,we provide two actual urban scenarios to further verify the effectiveness of the proposed algorithm.

关键词： Vehicle routing problem with constraints(VRPC) Spatiotemporal distance function Labor division strategy Ant colony algorithm(ACO)

Fast nuclear-spin gates and electrons−nuclei entanglement of neutral atoms in weak magnetic fields

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Frontiers of physics 2024年第2期19卷 179-203页

作者： xiao-feng Shi School of Physics Xidian UniversityXi’an 710071China

We present a novel class of Rydberg-mediated nuclear-spin entanglement in divalent atoms with global laser pulses.First,we show a fast nuclear-spin controlled phase gate of an arbitrary phase realizable either with two laser pulses when assisted by Stark shifts,or with three pulses.Second,we propose to create an electrons−nuclei-entangled state,which is named a super bell state(SBS)for it mimics a large Bell state incorporating three small Bell states.Third,we show a protocol to create a three-atom electrons-nuclei entangled state which contains the three-body W and Greenberger−Horne−Zeilinger(GHZ)states simultaneously.These protocols possess high intrinsic fidelities,do not require single-site Rydberg addressing,and can be executed with large Rydberg Rabi frequencies in a weak,Gauss-scale magnetic field.The latter two protocols can enable measurement-based preparation of Bell,hyperentangled,and GHZ states,and,specifically,SBS can enable quantum dense coding where one can share three classical bits of information by sending one particle.

关键词： nuclear-spin qubit electrons−nuclei entanglement super Bell state Greenberger−Horne−Zeilinger state Rydberg-mediated entanglement quantum dense coding

Tongue diagnosis based on hue-saturation value color space: controlled study of tongue appearance in patients treated with percutaneous coronary intervention for coronary heart disease

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Intelligent Medicine 2023年第4期3卷 252-257页

作者： Yumo Xia Qingsheng Wang XIAO Feng Xin’ang xiao Yiqin Wang Zhaoxia Xu Basic Medical College Shanghai University of Traditional Chinese MedicineShanghai 201203China

Objective To analyze the characteristics of tongue imaging color parameters in patients treated with percutaneous coronary intervention(PCI)and non-PCI for coronary atherosclerotic heart disease(CHD),and to observethe effects of PCI on the tongue images of patients as a basis for the clinical diagnosis and treatment of patientswith CHD.Methods This study used a retrospective cross-sectional survey to analyze tongue photographs and medicalhistory information from 204 patients with CHD between November 2018 and July 2020.Tongue images ofeach subject were obtained using the Z-BOX Series traditional Chinese medicine(TCM)intelligent diagnosisinstruments,the SMX System 2.0 was used to transform the image data into parameters in the HSV color space,and finally the parameters of the tongue image between patients in the PCI-treated and non-PCI-treated groupsfor CHD were analyzed.Results Among the 204 patients,112 were in the non-PCI treatment group(38 men and 74 women;average age of(68.76±9.49)years),92 were in the PCI treatment group(66 men and 26 women;average age of(66.02±10.22)years).In the PCI treatment group,the H values of the middle and tip of the tongue and the overall coating of thetongue were lower(P<0.05),while the V values of the middle,tip,both sides of the tongue,the whole tongueand the overall coating of the tongue were higher(P<0.05).Conclusion The color parameters of the tongue image could reflect the physical state of patients treated withPCI,which may provide a basis for the clinical diagnosis and treatment of patients with CHD.

关键词： Objective evaluation Tongue diagnosis Coronary heart disease Percutaneous coronary intervention Hue-saturation value color space Traditional Chinese medicine syndromes

Synthesis of the fluid machinery network in a circulating water system

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Chinese Journal of Chemical Engineering 2019年第3期27卷 587-597页

作者： Wei Gao XIAO Feng School of Chemical Engineering and Technology Xi'an Jiaotong University

Energy consumption of the fluid machinery network in a circulating water system takes up a large part of energy consumption in the process industry, so optimization on the network will enhance the economic and environmental performance of the industry. In this paper, a synthesis approach is proposed to obtain the optimal network structure. The effective height curves are used as tools to perform energy analysis, so that the potential placement of water turbines and auxiliary pumps can be determined with energy benefit. Then economic optimization is carried out, by the mathematical model with the total cost as the objective function, to identify the branches for water turbines and auxiliary pumps with economic benefit. In this way, the optimal fluid machinery network structure can be obtained. The results of case study indicate that the proposed synthesis approach to optimize the fluid machinery network will obtain more remarkable benefits on economy, compared to optimizing only the water turbine network or pump network. The results under different flowrates of circulating water reveal that using a water turbine to recover power or adding an auxiliary pump to save energy in branches are only suitable to the flowrate in a certain range.

关键词： Fluid machinery network Synthesis approach Flowrate range Network structure

Strategies in constructing covalent organic framework membranes for molecular sieving

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Science China Chemistry 2022年第5期65卷 836-839页

作者： Jie Li Shuang Zhao Bo Wang XIAO Feng Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials Key Laboratory of Cluster ScienceMinistry of EducationFrontiers Science Center for High Energy MaterialAdvanced Technology Research Institute(Jinan)School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

Membrane separation has emerged as one of the most economically and environmentally friendly technologies because of its low energy consumption,small footprint,and simple operation[1].

关键词： constructing separation membranes