Consensus-Based Approach to Day-Ahead Joint Local Energy-Reserve Market Design Considering Uncertainties of Renewable Energy

The penetration of distributed renewable generationprovides green energy to the local energy system. However, theuncertainties it brings to the system are becoming more andmore unacceptable, making it difficult to efficiently operate thelocal energy system. In a foreseeable future, there could bean increasing number of flexible resources, such as naturalgas power plants and interruptible demands, which providesolutions to these uncertainties. In this paper, a novel day-aheadenergy market design for the local energy system is proposed.This market allows its participants to trade day-ahead energyin a peer-to-peer approach. In addition, flexible resources canprovide up/down-ward reserves to the system through reservetrading, where the local system operator (LSO) takes chargeof reserve procurement. Then, to operate the market, a marketclearing model is proposed incorporating operating costs of theday-ahead and real time stages. A consensus-based approach isapplied which enables the market to clear in a decentralizedmethod. Finally, since the LSO bears the reserve procurementcosts as well as the operating costs in the real time stage,we then propose a cost reallocation model to transfer theexpenses to the renewables. Case studies demonstrate the validityand efficiency of the proposed market design, including localenergy trading facilitation, high and stable revenue preservation,high computation efficiency and prevention of strategic biddingbehaviors.

Distributed consensus-based algorithm for social welfare in smart grid with transmission losses

In this paper, we present a distributed consensus-based algorithm to solve the social welfare maximization problem. This is one of typical problems of distributed energy management in smart grid. In this problem, we consider not only the generator and demand, but also the transmission losses which make the feasibility set of the formulated problem a non-convex set. In solving this issue, we find a noticeable result that the primal problem has the same solution with a new convex optimization problem by getting the utmost out of the implied term in practice. Considering the general communication topology among generators and demands, we first design a finite step algorithm to make each generator and demand know the information of parameters of others.Then, we design a distributed algorithm and also prove the optimality and convergence of the proposed algorithm. Finally, the convergence and optimality are examined through extensive simulations.

A Consensus-Based Global Optimization Method with Adaptive Momentum Estimation

Objective functions in large-scalemachine-learning and artificial intelligence applications often live in high dimensions with strong non-convexity and massive local minima.Gradient-based methods,such as the stochastic gradient method and Adam[15],and gradient-freemethods,such as the consensus-based optimization(CBO)method,can be employed to find minima.In this work,based on the CBO method and Adam,we propose a consensus-based global optimization method with adaptive momentum estimation(Adam-CBO).Advantages of the Adam-CBO method include:It is capable of finding global minima of non-convex objective functions with high success rates and low costs.This is verified by finding the global minimizer of the 1000 dimensional Rastrigin function with 100%success rate at a cost only growing linearly with respect to the dimensionality.It can handle non-differentiable activation functions and thus approximate lowregularity functions with better accuracy.This is confirmed by solving a machine learning task for partial differential equations with low-regularity solutions where the Adam-CBO method provides better results than Adam.It is robust in the sense that its convergence is insensitive to the learning rate by a linear stability analysis.This is confirmed by finding theminimizer of a quadratic function.

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

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.

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

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.

Time-varying fault-tolerant formation tracking based cooperative control and guidance for multiple cruise missile systems under actuator failures and directed topologies

This paper studies time-varying fault-tolerant formation tracking problems for the multiple cruise missile system under directed topologies subjected to actuator failures. Firstly, the timevarying fault-tolerant formation tracking process for the multiple cruise missile system is divided into the guidance loop and the control loop. Then protocols are constructed to accomplish distributed fault-tolerant formation tracking in the guidance loop with the adaptive updating mechanism, in the condition where neither the knowledge about actuator malfunctions nor any global information of the communication topology remains available. Moreover, sufficient conditions to accomplish formation tracking are presented, and it is shown that the multiple cruise missile system can carry on the predefined time-varying fault-tolerant control (FTC) formation tracking through the active disturbances rejection controller (ADRC) and the proportion integration (PI) controller by the way of the fault-tolerant protocol utilizing the designed strategies, in the event of actuator failures. At last, numerical analysis and simulation are designed to verify the theoretical results.

Clinical practice guidelines for traditional Chinese medicine and integrated traditional Chinese and western medicine:a cross-sectional study of data analysis from 2010 to 2020

Objective With the increasing publication of clinical practice guidelines(CPG)for Traditional Chinese Medicine(TCM)and Integrated Traditional Chinese and Western Medicine(IM),the standardization and scientifiction of its formulation have gradually attracted many people’s attention.To offer an overview of TCM and IM CPGs published over the past decade and analyze their general characteristics and methodological quality.Methods The China National Knowledge Infrastructure(CNKI)and WANFANG databases were searched for clinical practice guidelines and expert consensus papers from January 2010 to June 2021.Two researchers independently completed the literature screening and cross-checking according to the inclusion and exclusion criteria of CPGs and extracted information on general characteristics and methodological quality of CPGs.Results According to the selection criteria,231 CPGs(EB-CPGs=119,CBCPGs=112)were selected and the number of CPGs published in the 11 years showed an overall upward trend.The vast majority of CPGs used the Western naming system for the diseases,and only 11 CPGs were named of TCM diseases or symptoms.TCM treatments were recommended in 223 CPGs.There were 156 ancient Chinese Medicine literature sources cited in 231 CPGs and opinions and experiences of 62 TCM experts cited in 37 CPGs.The methodological quality of EB-CPGs for TCM and IM were significantly better than CB-CPGs in 11 items.Only 60 EB-CPGs and 7 CB-CPGs designated clear criteria for grading quality of evidence and strength of the recommendations and 74 CPGs presented both the level of evidence and the strength of recommendations.We classified all CPGs according to whether or not they used GRADE,and the results showed that the CPGs using GRADE had higher methodological quality and more standardized reports.Conclusion This research has shown that the quantity and quality of CPGs in both TCM and IM have improved over the time span,but the methodological quality,especially evidence citation,and the use of criteria for grading quality of evidence and strength of the recommendations,still needs to further improvement in the future.

An adaptive distributed auction algorithm and its application to multi-AUV task assignment

The task assignment of multi-agent system has attracted considerable attention;however,the contradiction between computational complexity and assigning performance remains to be resolved.In this paper,a novel consensus-based adaptive optimization auction(CAOA)algorithm is proposed to greatly reduce the computation load while attaining enhanced system payoff.A new optimization scheme is designed to optimize the critical control parameter in the price update role of auction algorithm which can reduce the searching complexity in obtaining a better bidding price.With this new scheme,the CAOA algorithm is designed.Then the developed algorithm is applied to the multi-AUV task assignment problem for underwater detection mission in complex environments.The simulation and comparison studies verify the effectiveness and advantage of the CAOA algorithm.

A Hybrid Agent-based Model Predictive Control Scheme for Smart Community Energy System with Uncertain DGs and Loads

A multi-agent consensus-based market scheme is proposed for the cooperation of community and multiple microgrids(MGs)in a distributed,economic and hierarchal man-ner.The proposed community-based market framework with frequency regulation(FR)market is formulated as a two-level scheduling problem:the global decision-making process of community agent(CA)to participate in the FR market and the interaction and control process of local MGs to achieve collaboration in response to the global target with efficient pricing rules.Specifically,the model predictive control(MPC)is integrated with the consensus-based theory to allow MG to obtain an economic and reliable dispatch in the presence of uncertainties of distributed generators and loads.Thanks to the distributed nature of the proposed scheme,its robustness to communication issues has been strengthened and a win-win situation for all energy stakeholders can be achieved.The robustness of the proposed scheme is investigated in various conditions,including different implementation strategies,communication topologies,and the level of uncertainties.

A systematic review of patient reported outcome measures (PROMs) and quality of life reporting in patients undergoing laparoscopic cholecystectomy

Patient reported outcome measures(PROMs)provide a valuable means of measuring outcomes subjectively from a patient's perspective,facilitating the assessment of service quality across healthcare providers,and assisting patients and clinicians in shared decision making.The primary aim of this systematic review was to critically appraise all historic studies evaluating patient reported quality of life,in adult patients undergoing laparoscopic cholecystectomy for symptomatic gallstones.The secondary aim was to perform a quality assessment of cholecystectomy-specific PROM-validation studies.A literature review was performed in PubMed,Google ScholarTM,the Cochrane Library,Medline,CINAHL,EMBASE and PsychINFO databases up to September 2017.Study characteristics,PROM-specific details and a bias assessment were summarised for non-validation studies.A COnsensus-based Standards for the selection of health Measurement INstruments(COSMIN)analysis was performed to assess the methodological quality of identified PROM-validation studies.Fifty one studies were found to evaluate health-related quality of life(HRQoL)after laparoscopic cholecystectomy.Although 94.1%of these studies included PROMs as a primary outcome measure,<20%provided level 1 evidence through randomised controlled trials(RCTs).There was significant variation in the selection and reporting of PROMs,with no studies declaring patient involvement in PROM selection,and 88.2%of studies failing to document the management of missing data points,or non-returned surveys(33.3%).In the 6 PROM-validation studies identified,only 5 psychometric properties were evaluated,the findings of which were limited due to the small number of studies.This systematic review identifies a lack in consistency of study design and PRO reporting in clinical trials.Whilst an increasing number of studies are being performed to evaluate PROs,a lack of adherence to existing PRO administration and reporting guidelines is continuing to negatively affect study quality.We recommend that future clinical trials utilizing PROs should adhere to established comprehensive guidelines as described.

Fully Distributed Economic Dispatch for Cyber-physical Power System with Time Delays and Channel Noises

Economic dispatch problem(EDP)is a fundamental optimization problem in power system operation,which aims at minimizing the total generation cost.In fact,the power grid is becoming a cyber-physical power system(CPPS).Therefore,the quality of communication is a key point.In this paper,considering two important factors,i.e.,time delays and channel noises,a fully distributed consensus based algorithm is proposed for solving EDP.The critical maximum allowable upper bounds of heterogeneous communication delays and self-delays are obtained.It should be pointed out that the proposed algorithm can be robust against the time-varying delays and channel noises considering generator constraints.In addition,even with time-varying delays and channel noises,the power balance of supply and demand is not broken during the optimization.Several simulation studies are presented to validate the correctness and superiority of the developed results.