Improved Voltage Control Strategy for Photovoltaic Grid-Connected System Based on DoubleLayer Coordination Control

An improved automatic voltage coordination control strategy （AVCCS） based on ;automatic voltage control （AVC） and battery energy storage control （BESC） is proposed for photovoltaic grid-connected system （PVGS） to mitigate the voltage fluctuations caused by environmental disturbances. Only AVC is used when small environ- mental disturbances happen, while BESC is incorporated with AVC to restrain the voltage fluctuations when large disturbances happen. An adjustable parameter determining the allowed amplitudes of voltage fluctuations is introduced to realize the above switching process. A benchmark low voltage distribution system including ]？VGS is established by using the commercial software Dig SILENT. Simulation results show that the voltage under AVCCS satisfies the IEEE Standard 1547, and the installed battery capacity is also reduced. Meanwhile, the battery＇s service life is ex- tended by avoiding frequent charges/discharges in the control process.

Game Theory Based Decision Coordination Strategy of Agricultural Logistics Service Information System

Under the background of“Internet plus”rapid development,the agricultural logistics industry should apply information technology to every link of the agricultural product logistics industry chain.By making full use of the decision making module of the agricultural logistics information system,we can realize the full sharing of information and data resources,which makes the decision-making scheme of the agricultural logistics information system more optimized.In real economic society,the uncertainty and mismatch between the customer’s logistics service demand and the logistics service capability that the logistics service function provider can provide,that is,when the two information are asymmetric,how to use the third-party contract to coordinate the income and profit distribution of the two,to make the information system decision making more reasonable?This paper mainly studies the coordination scheme of agricultural logistics information system decision making under uncertain output and demand information by introducing the spot market.A joint coordination strategy based on revenue sharing and penalty feedback contracts proposes decentralized decision making based on game theory.Experiments show that the flexible ordering strategy proposed in this paper can reduce the logistics service supply chain’s uncertainty and significantly improve the logistics service supply chain’s overall income level through coordination contracts.

Optimal design of coordination control strategy for distributed generation system

This paper presents a novel design procedure for optimizing the power distribution strategy in distributed generation system. A coordinating controller, responsible to distribute the total load power request among multiple DG units, is suggested based on the conception of hierarchical control structure in the dynamic system. The optimal control problem was formulated as a nonlinear optimization problem subject to set of constraints. The resulting problem was solved using the Kuhn-Tucker method. Computer simulation results demonstrate that the proposed method can provide better efficiency in terms of reducing total costs compared to existing methods. In addition, the proposed optimal load distribution strategy can be easily implemented in real-time thanks to the simplicity of closed-form solutions.

Multi-agent system application in accordance with game theory in bi-directional coordination network model

The multi-agent system is the optimal solution to complex intelligent problems. In accordance with the game theory, the concept of loyalty is introduced to analyze the relationship between agents' individual income and global benefits and build the logical architecture of the multi-agent system. Besides, to verify the feasibility of the method, the cyclic neural network is optimized, the bi-directional coordination network is built as the training network for deep learning, and specific training scenes are simulated as the training background. After a certain number of training iterations, the model can learn simple strategies autonomously. Also,as the training time increases, the complexity of learning strategies rises gradually. Strategies such as obstacle avoidance, firepower distribution and collaborative cover are adopted to demonstrate the achievability of the model. The model is verified to be realizable by the examples of obstacle avoidance, fire distribution and cooperative cover. Under the same resource background, the model exhibits better convergence than other deep learning training networks, and it is not easy to fall into the local endless loop.Furthermore, the ability of the learning strategy is stronger than that of the training model based on rules, which is of great practical values.

Advances on Axial Coordination Design of Single‑Atom Catalysts for Energy Electrocatalysis:A Review

Single-atom catalysts(SACs)have garnered increasingly growing attention in renewable energy scenarios,especially in electrocatalysis due to their unique high efficiency of atom utilization and flexible electronic structure adjustability.The intensive efforts towards the rational design and synthesis of SACs with versatile local configurations have significantly accelerated the development of efficient and sustainable electrocatalysts for a wide range of electrochemical applications.As an emergent coordination avenue,intentionally breaking the planar symmetry of SACs by adding ligands in the axial direction of metal single atoms offers a novel approach for the tuning of both geometric and electronic structures,thereby enhancing electrocatalytic performance at active sites.In this review,we briefly outline the burgeoning research topic of axially coordinated SACs and provide a comprehensive summary of the recent advances in their synthetic strategies and electrocatalytic applications.Besides,the challenges and outlooks in this research field have also been emphasized.The present review provides an in-depth and comprehensive understanding of the axial coordination design of SACs,which could bring new perspectives and solutions for fine regulation of the electronic structures of SACs catering to high-performing energy electrocatalysis.

Regional Evolution Features and Coordinated Development Strategies for Northeast China

Northeast China, as the most important production base of agriculture, forestry, and livestock-breeding as well as the old industrial base in the whole country, has been playin a key role in the construction and development of China＇s economy. However, after the policy of reform and open-up was taken in China. the economic development speed and efficiency ofthis area have turned to be evidently lower than those of coastal area and the national average level as well, which is so-called ＇Northeast Phenomenon＇ and ＇Neo-Northeast Phenomenon＇. In terms of those phenomena, this paper firstly reviews the spatial and temporal features of the regional evolution of this area so as to unveil the profound forming causes of ＇Northeast Phenomena＇ and ＇Neo-Northeast Phenomena＇. And then the paper makes a further exploration into the status quo of this region and its forming causes by analyzing its economy gross, industrial structure, product structure, regional eco-categories, etc. At the end of the paper, the authors put forward the basic coordinated development strategies for Northeast China. namely we can revitalize this area by means of adjustment of economic structure, regional coordination, planning urban and rural areas as a whole, institutional innovation, etc.

Coordination of multiple mobile robots with limited communication range in pursuit of single mobile target in cluttered environment

This paper addresses the problem of coordinating multiple mobile robots in searching for and capturing a mobile target,with the aim of reducing the capture time.Compared with the previous algorithms,we assume that the target can be detected by any robot and captured successfully by two or more robots.In this paper,we assume that each robot has a limited communication range.We maintain the robots within a mobile network to guarantee the successful capture.In addition,the motion of the target is modeled and incorporated into directing the motion of the robots to reduce the capture time.A coordination algorithm considering both aspects is proposed.This algorithm can greatly reduce the expected time of capturing the mobile target.Finally,we validate the algorithm by the simulations and experiments.

Coordinated control strategy for robotic-assisted gait training with partial body weight support

Walking is the most basic and essential part of the activities of daily living. To enable the elderly and non-ambulatory gait-impaired patients, the repetitive practice of this task, a novel gait training robot(GTR) was designed followed the end-effector principle, and an active partial body weight support(PBWS) system was introduced to facilitate successful gait training. For successful establishment of a walking gait on the GTR with PBWS, the motion laws of the GTR were planned to enable the phase distribution relationships of the cycle step, and the center of gravity(COG) trajectory of the human body during gait training on the GTR was measured. A coordinated control strategy was proposed based on the impedance control principle. A robotic prototype was developed as a platform for evaluating the design concepts and control strategies. Preliminary gait training with a healthy subject was implemented by the robotic-assisted gait training system and the experimental results are encouraging.

Coordinating Preventive Strategies and Restoration under Extreme Weather Conditions

It has been well identified that the extreme events significantly impact the system operation. In this work, a comprehensive operating strategy, which coordinates the preventive strategies and system restoration, was proposed. A re-dispatch model that limits the potential loss under extreme events, as well as provides adequate resources for system restoration after the extreme events, was proposed. An optimal power flow based method was established to solve the proposed model. The availabilities of components and the remaining system due to the extreme events were restored by extending the EPRI’s System Restoration Navigator (SRN) with a little modification. Case studies demonstrate the proposed model and methods.

Research and Design of Coordinated Control Strategy for Smart Electromechanical Actuator System

In order to improve the frequency response and anti-interference characteristics of the smart electromechanical actuator(EMA)system,and aiming at the force fighting problem when multiple actuators work synchronously,a multi input multi output(MIMO)position difference cross coupling control coordinated strategy based on double‑closed-loop load feedforward control is proposed and designed.In this strategy,the singular value method of return difference matrix is used to design the parameter range that meets the requirements of system stability margin,and the sensitivity function and the H_(∞)norm theory are used to design and determine the optimal solution in the obtained parameter stability region,so that the multi actuator system has excellent synchronization,stability and anti-interference.At the same time,the mathematical model of the integrated smart EMA system is established.According to the requirements of point-to-point control,the controller of double-loop control and load feedforward compensation is determined and designed to improve the frequency response and anti-interference ability of single actuator.Finally,the 270 V high-voltage smart EMA system experimental platform is built,and the frequency response,load feedforward compensation and coordinated control experiments are carried out to verify the correctness of the position difference cross coupling control strategy and the rationality of the parameter design,so that the system can reach the servo control indexes of bandwidth 6 Hz,the maximum output force 20000 N and the synchronization error≤0.1 mm,which effectively solves the problem of force fighting.

Ecological and Environmental Protection Requirements in China s Regional Coordinated Development Strategy in the New Era

Starting from the historical evolution of China s regional coordinated development policy and practice,three stages of"enlightenment stage","development stage"and"maturity stage",as well as the connotation,characteristics and content of implementing regional coordinated development strategy were analyzed.On this basis,from different aspects of industrial distribution,pollutant characteristics and regional environmental protection policy,the existing ecological and environmental protection problems in China s regional coordinated development in the new era were analyzed,and some suggestions for the next step were put forward.It is necessary to follow the"four ones"concept from the overall point of view,implement"three lines and one list"from the perspective of the width of the access red line,strengthen"joint prevention and control"from the perspective of the depth of regional regulation,deepen the"planning environmental impact assessment"from the perspective of the breadth of industrial distribution,and promote the"green-way model"from the perspective of ecological low carbon.

Research on the Influence Factors and Coordinated Control Strategies between Unit and Grid for Isolated Power System

As the existing coordinated control strategies between grid and unit have limitations in isolated power system, this paper introduces new coordinated control strategies which can improve the stability of isolated system operation. This paper analyzes the power grid side and unit side influence factors on the isolated power system. The dynamic models which are suitable for islanding operation are applied to simulate and analyze the stability and dynamic characteristics of the isolated power system under the conditions of different load disturbances and governor parameters. With considering the differences of frequency characteristics between the interconnected and isolated power system, the adjusting and optimization methods of under frequency load shedding are proposed to meet the frequency stability requirements simultaneously in the two cases. Not only proper control strategies of the power plant but the settings of their parameters are suggested to improve the operation stability of the isolated power system. To confirm the correctness and effectiveness of the method mentioned above, the isolated system operation test was conducted under the real power system condition, and the results show that the proposed coordinated control strategies can greatly improve stability of the isolated power system.

Development of Agricultural Product Logistics in Tianjin in the Context of the Coordinated Development Strategy of Beijing-Tianjin-Hebei Region

Since February 26,2014,Chinese president Xi Jinping of the Central Committee of the Communist Party of China listened to the report on the coordinated development of Beijing-Tianjin-Hebei Region and delivered an important speech,and officially raised the coordinated development of Beijing-Tianjin-Hebei Region as a major national strategy,the integration of Beijing-Tianjin-Hebei Region has entered the"fast lane".Guided by accelerating the construction of agricultural product supply areas,agricultural high-tech industry demonstration areas,and agricultural product logistics center areas,Tianjin seizes the opportunity of coordinated development of Beijing-Tianjin-Hebei Region,brings into full play to the advantages of Tianjin s three-dimensional transportation network,perfect market system,high-quality port services,rapid growth of cold chain and e-commerce,to promote the faster and better development of Tianjin s agriculture.In addition,focusing on comprehensively improving Tianjin s regional agricultural product logistics service capabilities,Tianjin is establishing a distribution center for agricultural products,an e-commerce center,and a high-end agricultural product distribution center serving the Beijing-Tianjin-Hebei Region,to promote the construction of Tianjin agricultural product logistics center.

A Study on the Strategies of the Coordinated Development of Education in Jing-Jin-Ji Region

Nowadays, the coordinated development of Jing-Jin-Ji has been a national strategy, and has brought unprecedented opportuniyies for the development fof education in this region. However, there are also some bottlenecks that restrict the development of this region. Therefore, this paper will analyze some typical cases of coordinated development of education in this region and put forward some suggestions and strategies to provide some references for the development.

各国药典标准残留溶剂控制与ICH Q3C协调策略分析

目的分析各国药典残留溶剂控制与国际人用药品注册技术协调会残留溶剂指导原则(ICH Q3C)的协调策略,为《中华人民共和国药典》(简称《中国药典》)残留溶剂与ICH Q3C协调提供思路和方案。方法通过文献调研和梳理,对比各国药典残留溶剂控制与ICH Q3C的协调进程,分析国外主流药典残留溶剂控制与ICH Q3C协调实施策略,梳理《中国药典》与国外药典残留溶剂控制的差异。结果《中国药典》残留溶剂的相关控制有必要与ICH Q3C进行协调。结论建议在结合中国国情的基础上,借鉴国外药典与ICH Q3C协调的经验,稳步推进我国药典残留溶剂控制与ICH的整体协调。

区域协调发展:历程、成效、问题与机制

促进区域协调发展是实现中国式现代化的关键支撑,是加快构建新发展格局、着力推动高质量发展的重要内容。改革开放以来,中国的区域发展战略经历了非均衡发展、初步探索、加快实施及全面深化四个阶段,各阶段的战略重点各异,共同构成丰富的历史脉络。新时代以来,随着区域协调发展战略深入实施,我国区域协调发展取得显著成效,但也出现了一些新情况新问题,表现为东中西不平衡问题依然突出、南北分化态势开始凸显、特殊类型地区发展不充分、区域间利益关系尚未理顺,难以适应区域协调发展战略新要求。建议在区域协调发展战略实施中强化区际关系协调的职能,建立战略融合机制、深化区域合作和互助机制、健全资源开发利益补偿机制、完善生态产品价值实现机制、构建粮食主产区利益补偿机制、健全城市群都市圈一体化发展机制及完善基本公共服务均等化机制,推动区域协调发展走深走实。

单向功率混合型MMC及其启动/直流短路故障穿越控制

单向功率传输场景下,挖掘桥臂内部全桥及半桥子模块的协调控制空间,提出可节省器件的类半桥子模块及由其与全桥子模块构成的新型单向功率混合型模块化多电平换流器(MMC)。针对启动阶段和直流短路故障穿越期间潜在的电容电压不均衡及电压、电流应力问题,提出适用于该拓扑的启动策略。基于直流环流注入控制实现直流短路故障穿越,保证设备在整个运行区域可靠运行。在MATLAB/Simulink中搭建仿真模型,验证所提控制策略的可行性和有效性。相比现有的混合型MMC,所提拓扑在保证直流短路故障穿越能力的前提下,节省半桥子模块内部的一个开关器件,具有较好的成本优势。

重大需求强化国家战略科技力量模式机制研究——跨部门跨层次激励内部协同视角

针对当前国家战略科技力量体系上下有脱节、内部少协同、内外缺联动等问题,强化国家战略科技力量协同尤为重要。基于当前国家战略科技力量的研究现状,论文提出跨部门跨层次激励的内部协同视角并探究重大需求强化国家战略科技力量的协同机制与模式。从国家战略科技力量的自身构成、组织方式和国家战略体系的能力绩效3个维度考察重大需求强化国家战略科技力量内部协同的潜能优势,从事前、事中和事后3个阶段阐明重大需求强化国家战略科技力量内部协同的作用机制,从而分析指出先军领导追随型、战略联盟合作型、开放自由组合型、平台共享驱动型、应急动员指令型等重大需求强化国家战略科技力量的协同模式。以粤港澳大湾区为例,剖析集成电路产业发展重大需求强化粤港澳大湾区战略科技力量的实践举措。最后,从加强党对国家战略科技力量的集中统一领导、以“专项小组”推动国家战略科技力量协同、完善国家战略科技力量体系的法治保障、构建和强化国家战略科技力量数字平台等4个方面提出对策建议。

复杂环境下无人机路径规划及其改进型人工兔优化

针对复杂障碍物环境下无人机安全、高效飞行的路径规划问题,探讨其优化模型的设计与求解算法。模型设计中,以距离、角度、高度及飞行威胁代价为性能指标,以地域、空域障碍物为约束,建立基于权重系数法与柱坐标系的单性能指标路径规划模型;针对人工兔优化算法存在初始种群分布不均匀、勘探能力和开采能力不平衡,以及局部搜索能力不足的问题,利用SPM混沌映射改善初始种群分布;借助精英个体引导策略增强局部搜索能力;利用改进型能量收缩策略平衡全局与局部搜索能力,提出一种计算复杂度由种群规模确定且能求解大规模优化问题的改进型人工兔优化算法。实验表明,已获路径规划模型的路径规划方案能在一定程度上缓解航迹点数的增加对求解性能的影响,同时优化算法处理大规模优化问题及复杂障碍物威胁环境下无人机路径规划问题具有明显优势。

食品检验检测中不同标准体系的冲突与协调策略探讨

本文阐述了不同国家和地区标准体系、国内行业标准与国家标准、国际标准与国内标准之间的冲突表现,同时分析了冲突产生的原因,如制定主体和目的差异、科技发展不平衡以及缺乏沟通协调机制。并针对这些冲突问题,提出了涵盖国际、国内和企业3个层面的协调策略,旨在促进食品检验检测标准体系的完善与协调发展,保障食品安全和产业健康发展。