Effectiveness evaluation of the joint operation system is an important basis for the demonstration and development of weapon equipment.With the consideration that existing models of system effectiveness evaluation sel...Effectiveness evaluation of the joint operation system is an important basis for the demonstration and development of weapon equipment.With the consideration that existing models of system effectiveness evaluation seldom describe the structural relationship among equipment clearly as well as reflect the dynamic,the analog-to-digital converter-graphical evaluation and review technique(ADC-GERT)network parameter estimation model is proposed based on the ADC model and the joint operation system structure.Firstly,analysis of the joint operation system structure and operation process is conducted to build the GERT network,where equipment subsystems are nodes and activities are directed arches.Then the mission effectiveness of equipment subsystems is calculated by the ADC model.The probability transfer parameters are modified by the mission effectiveness of equipment subsystems based on the Bayesian theorem,with the ADC-GERT network parameter estimation model constructed.Finally,a case study is used to validate the efficiency and dynamic of the ADC-GERT network parameter estimation model.展开更多
In the process industry, automation and process control systems are widely implemented, information integration is however far away from satisfactory. It remains a hard job for senior managers to make decisions based ...In the process industry, automation and process control systems are widely implemented, information integration is however far away from satisfactory. It remains a hard job for senior managers to make decisions based on the plant-wide real-time integrated information. This paper proposes a multi-layer information integration platform. In the data integration level, the standard for the exchange of product (STEP) and the extensible markup language (XML) are used to unify these data of the chemical process. In the model integration level, the models are integrated by using the neutral model repository and CAPE-OPEN. In the integration of process task, the common object request broker architecture (CORBA) is used as the communication mediator. The XML is taken as the data standard. A uniform information platform is thus constructed and realized. The proposed information integration platform is satisfactorily implemented to solve the Tennessee Eastman (TE) problem.展开更多
A simple method for calculating the 3D coordinates of points on a micro object in a multi camera system is proposed. It simplifies the algorithms used in traditional computer vision system by eliminating the calculat...A simple method for calculating the 3D coordinates of points on a micro object in a multi camera system is proposed. It simplifies the algorithms used in traditional computer vision system by eliminating the calculation of the CCD (charge coupled device) camera parameters and the relative position between cameras, and using solid geometry in the calculation procedures instead of the calculation of the complex matrixes. The algorithm was used in the research of generating a virtual magnified 3D image of a micro object to be operated in a micro operation system, and the satisfactory results were obtained. The application in a virtual tele operation system for a dexterous mechanical gripper is under test.展开更多
Teleoperation system plays an important role in executing task under hazard environment. As the computer networks such as the Internet are being used as the communication channel of teleoperation system, varying time ...Teleoperation system plays an important role in executing task under hazard environment. As the computer networks such as the Internet are being used as the communication channel of teleoperation system, varying time delay causes the overall system unstable and reduces the performance of transparency. This paper proposed twelve operation modes with different control schemes for teleoperation on the Internet with time delay. And an optimal operation mode with control scheme was specified for teleoperation with time delay, based on the tradeoff between passivity and transparency properties. It experimentally confirmed the validity of the proposed optimal mode and control scheme by using a simple one DOF master-slave manipulator system.展开更多
The increasing penetration of wind power poses challenges to the power grid operation and scheduling. Yet, if the uncertainty of wind power can be economically and effec tively managed on the source side, it can drive...The increasing penetration of wind power poses challenges to the power grid operation and scheduling. Yet, if the uncertainty of wind power can be economically and effec tively managed on the source side, it can drive the power grids towards renewable-dominant future. In this paper, an en hanced scheduling strategy for wind farm−flexible load joint op eration system (WF-FLJOS) is proposed. The proposed strategy is designed to manage the uncertainty of wind power on the generation side when integrated into a large-scale power grid. Moreover, it can contribute to saving energy costs on the load side. Compared with the current wind farm operation rules, more stringent assessment requirements are put forward for wind power output accuracy, and the internal organization framework of WF-FLJOS is designed. For potential power vio lations of wind farms and flexible loads, the violation penalty mechanisms are developed to regulate the behavior of the par ticipants. The joint operation model of the WF-FLJOS is pro posed and the submission and tracking approach of the genera tion schedule for the wind farm is investigated. Numerical re sults indicate that the proposed strategy can not only improve the ability of the wind farm to track the generation schedule, but also consider the benefits of both the farm side and the load side. Meanwhile, the proposed strategy effectively reduces the schedule adjustment pressure on the main grid caused by the rolling correction mode of the intraday schedule for wind farms.展开更多
Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longe...Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longer period.A multi-objective genetic algorithm(MOGA)and state of charge(SOC)region division for the batteries are introduced to solve the objective function and configuration of the system capacity,respectively.MATLAB/Simulink was used for simulation test.The optimization results show that for a 0.5 MW wind power and 0.5 MW photovoltaic system,with a combination of a 300 Ah lithium battery,a 200 Ah lead-acid battery,and a water storage tank,the proposed strategy reduces the system construction cost by approximately 18,000 yuan.Additionally,the cycle count of the electrochemical energy storage systemincreases from4515 to 4660,while the depth of discharge decreases from 55.37%to 53.65%,achieving shallow charging and discharging,thereby extending battery life and reducing grid voltage fluctuations significantly.The proposed strategy is a guide for stabilizing the grid connection of wind and solar power generation,capability allocation,and energy management of energy conservation systems.展开更多
This paper focuses on AI intelligence as the fundamental direction to conduct research on information system operation and maintenance(O&M).Combining current AI-supported technologies in information system O&M...This paper focuses on AI intelligence as the fundamental direction to conduct research on information system operation and maintenance(O&M).Combining current AI-supported technologies in information system O&M,it proposes O&M strategies such as intelligent fault prediction and diagnosis,intelligent system performance optimization,intelligent system security protection,and adaptive system O&M implementation.Practical applications reveal that AI intelligence technology offers significant advantages in information system O&M,effectively addressing pain points of traditional O&M techniques,such as low fault prediction rates,slow repair speeds,poor security interception,and high labor costs.This substantially enhances the effectiveness of information system O&M.展开更多
Digital twin shows broad application prospects in the aerospace field.This paper introduces a generalized satellite digital twin system in detail.With the innovative design concepts of modularization,generalization an...Digital twin shows broad application prospects in the aerospace field.This paper introduces a generalized satellite digital twin system in detail.With the innovative design concepts of modularization,generalization and modeling,on the one hand,the system has successfully achieved the reuse of software modules among different satellite models;on the other hand,it has achieved the reuse of software modules between the digital twin and the testing system,significantly improving the development efficiency of the digital twin system.The paper elaborates on the technical architecture and application fields of this digital twin system,and further prospects its future development.At the same time,through a real inorbit case,the engineering value of the digital twin system is strongly demonstrated.展开更多
The rapid expansion of photovoltaic(PV)deployment poses new challenges for large-scale and distributed maintenance,particularly in fishery-PV complementary plants where panels are deployed over water surfaces.This pap...The rapid expansion of photovoltaic(PV)deployment poses new challenges for large-scale and distributed maintenance,particularly in fishery-PV complementary plants where panels are deployed over water surfaces.This paper presents the design and implementation of an intelligent operation and maintenance(O&M)system that integrates a 3D holographic digital twin cloud platform with UAV-assisted inspection and localized cleaning.The proposed system supports multi-source data acquisition,including UAV imagery,infrared sensing,and DustIQ-based soiling monitoring,and provides real-time visualization of the PV plant through 1:13D reconstruction.UAVs are employed for both autonomous inspections,covering defects such as soiling,bird droppings,bypass diode faults,and panel disconnections and targeted cleaning in small water-covered areas.Field trials were conducted at Riyue and Chebu PV plants,with small-scale UAV cleaning validation in Chebu fish ponds.Results demonstrated that the system achieves efficient task scheduling,fault detection,and localized cleaning,thereby improving O&M efficiency,reducing costs,and enabling digitalized and intelligent management for large-scale PV stations.展开更多
It is fundamental and useful to investigate how deep learning forecasting models(DLMs)perform compared to operational oceanography forecast systems(OFSs).However,few studies have intercompared their performances using...It is fundamental and useful to investigate how deep learning forecasting models(DLMs)perform compared to operational oceanography forecast systems(OFSs).However,few studies have intercompared their performances using an identical reference.In this study,three physically reasonable DLMs are implemented for the forecasting of the sea surface temperature(SST),sea level anomaly(SLA),and sea surface velocity in the South China Sea.The DLMs are validated against both the testing dataset and the“OceanPredict”Class 4 dataset.Results show that the DLMs'RMSEs against the latter increase by 44%,245%,302%,and 109%for SST,SLA,current speed,and direction,respectively,compared to those against the former.Therefore,different references have significant influences on the validation,and it is necessary to use an identical and independent reference to intercompare the DLMs and OFSs.Against the Class 4 dataset,the DLMs present significantly better performance for SLA than the OFSs,and slightly better performances for other variables.The error patterns of the DLMs and OFSs show a high degree of similarity,which is reasonable from the viewpoint of predictability,facilitating further applications of the DLMs.For extreme events,the DLMs and OFSs both present large but similar forecast errors for SLA and current speed,while the DLMs are likely to give larger errors for SST and current direction.This study provides an evaluation of the forecast skills of commonly used DLMs and provides an example to objectively intercompare different DLMs.展开更多
The accurate selection of operational parameters is critical for ensuring the safety,efficiency,and automation of Tunnel Boring Machine(TBM)operations.This study proposes a similarity-based framework integrating model...The accurate selection of operational parameters is critical for ensuring the safety,efficiency,and automation of Tunnel Boring Machine(TBM)operations.This study proposes a similarity-based framework integrating model-based boring indexes(derived from rock fragmentation mechanisms)and Euclidean distance analysis to achieve real-time recommendations of TBM operational parameters.Key performance indicators-thrust(F),torque(T),and penetration(p)-were used to calculate three model-based boring indexes(a,b,k),which quantify dynamic rock fragmentation behavior.A dataset of 359 candidate samples,reflecting diverse geological conditions from the Yin-Chao water conveyance project in Inner Mongolia,China,was utilized to validate the framework.The system dynamically recommends parameters by matching real-time data with historical cases through standardized Euclidean distance,achieving high accuracy.Specifically,the mean absolute error(MAE)for rotation speed(n)was 0.10 r/min,corresponding to a mean absolute percentage error(MAPE)of 1.09%.For advance rate(v),the MAE was 3.4 mm/min,with a MAPE of 4.50%.The predicted thrust(F)and torque(T)values exhibited strong agreement with field measurements,with MAEs of 270 kN and 178 kN∙m,respectively.Field applications demonstrated a 30%reduction in parameter adjustment time compared to empirical methods.This work provides a robust solution for real-time TBM control,advancing intelligent tunneling in complex geological environments.展开更多
This paper proposed a new systematic approach-functional evidential reasoning model(FERM) for exploring hazardous chemical operational accidents under uncertainty. First, FERM was introduced to identify various causal...This paper proposed a new systematic approach-functional evidential reasoning model(FERM) for exploring hazardous chemical operational accidents under uncertainty. First, FERM was introduced to identify various causal factors and their performance changes in hazardous chemical operational accidents, along with determining the functional failure link relationships. Subsequently, FERM was employed to elucidate both qualitative and quantitative operational accident information within a unified framework, which could be regarded as the input of information fusion to obtain the fuzzy belief distribution of each cause factor. Finally, the derived risk values of the causal factors were ranked while constructing multi-level accident causation chains to unveil the weak links in system functionality and the primary roots of operational accidents. Using the specific case of the “1·15” major explosion and fire accident at Liaoning Panjin Haoye Chemical Co., Ltd., seven causal factors and their corresponding performance changes were identified. Additionally, five accident causation chains were uncovered based on the fuzzy joint distribution of the functional assessment level(FAL) and reliability distribution(RD),revealing an overall increase in risk along the accident evolution path. The research findings demonstrated that FERM enabled the effective characterization, rational quantification and accurate analysis of the inherent uncertainties in hazardous chemical operational accident risks from a systemic perspective.展开更多
Loday introduced di-associative algebras and tri-associative algebras motivated by periodicity phenomena in algebraic K-theory.The purpose of this paper is to study the splittings of operations on di-associative algeb...Loday introduced di-associative algebras and tri-associative algebras motivated by periodicity phenomena in algebraic K-theory.The purpose of this paper is to study the splittings of operations on di-associative algebras and tri-associative algebras.We introduce the notion of a quad-dendriform algebra,which is a splitting of a di-associative algebra.We show that a relative averaging operator on dendriform algebras gives rise to a quad-dendriform algebra.Furthermore,we introduce the notion of six-dendriform algebras,which are splittings of the tri-associative algebras,and demonstrate that homomorphic relative averaging operators induce six-dendriform algebras.展开更多
In order to investigate the alternate operation characteristics of a solar-ground source heat pump system（SGSHPS）,various alternate operation modes are put forward and defined.A two-dimensional mathematical model wi...In order to investigate the alternate operation characteristics of a solar-ground source heat pump system（SGSHPS）,various alternate operation modes are put forward and defined.A two-dimensional mathematical model with freezing/melting phase changes is developed for the heat transfer analysis of the soil.Based on the numerical solution of the model,the variation trends of underground soil temperature of the SGSHPS operated in various alternate operation modes are discussed.The results indicate that,for the day-night and short-time interval alternate operation modes without solar energy,the operation time fraction of a solar heat source should be confined to from 50% to 58% when operated in an alternate period of 24 h.Meanwhile,the disadvantages of a natural resumption of soil temperature can be overcome effectively by solar energy filling,and an optimal operation effect can be achieved by integrating the mode of solar energy filling with other alternate modes.In addition,the accuracy of the presented model is verified by the experimental data of borehole wall temperatures.The conclusions can provide a reference for the optimization operation of the SGSHPS.展开更多
An output-only modal identification method by a combination use of the peak-picking method and the cross spectrum methods are presented. Meanwhile, a novel mode shape optimum method of the deck is proposed. The method...An output-only modal identification method by a combination use of the peak-picking method and the cross spectrum methods are presented. Meanwhile, a novel mode shape optimum method of the deck is proposed. The methods are applied to the operational modal identification system of the Runyang Suspension Bridge, which can be used to obtain the modal parameters of the bridge from out-only data sets collected by its structural health monitoring system （SHMS）. As an example, the vibration response data of the deck, cable and tower recorded during typhoon Matsa excitation are used to illustrate the program application. Some of the modal frequencies observed from deck vibration responses are also found in the vibration responses of the cable and the tower. The results show that some modal shapes of the deck are strongly coupled with the cable and the tower. By comparing the identification results from the operational modal system with those from field measurements, a good agreement between them is achieved, but some modal frequencies identified from the operational modal identification system （OMIS）, such as L1 and L2, obviously decrease compared with those from the field measurements.展开更多
Basing on a viewpoint of all sided water producing system,a comprehensive analysis of the operation status and the relationship between each working unit in water producing system,including coagulation,sedimentation...Basing on a viewpoint of all sided water producing system,a comprehensive analysis of the operation status and the relationship between each working unit in water producing system,including coagulation,sedimentation and filtration etc.was made.By investigating the influence of backwashing consumption,the amount of sludge ejected from sedimentation tank and coagulant ratio upon the cost,the cost effective function of the system was presented.Afterwards,the solution was found out and the corresponding computer program was developed.When applied with real world data,it proved that this method significantly reduced the water producing cost.展开更多
This article summarizes the theoretical results in Laboratory economy, defines the model of the laboratory economic of schools and enterprises to build, analyzes its organizational model and elaborates its operational...This article summarizes the theoretical results in Laboratory economy, defines the model of the laboratory economic of schools and enterprises to build, analyzes its organizational model and elaborates its operational mechanism, so as to provide a reference for School-enterprise cooperation, laboratory-economic development and innovation performance of Laboratory economy established by university and enterprise.展开更多
It is not only meteorological problems for the medium-range numerical weather prediction (NWP) research to be in operation,but also engineering and technological problems.Here we gener- ally described the results of r...It is not only meteorological problems for the medium-range numerical weather prediction (NWP) research to be in operation,but also engineering and technological problems.Here we gener- ally described the results of research,engineering construction,operation information and testing,in the course of set-up of medium-range NWP operation system in the China National Meteorological Center.展开更多
In this research, LINGO is used successfully to solve the water supply system′s optimal operation model. Firstly, the language of LINGO and the using method were studied intensively, on the basis of which the model w...In this research, LINGO is used successfully to solve the water supply system′s optimal operation model. Firstly, the language of LINGO and the using method were studied intensively, on the basis of which the model was transformed to LINGO form and solved successfully. Secondly, the research on the interface between LINGO and the popular office software was made. The optimization software was developed, which had Excel as the workspace and LINGO as the core of computation. Through practice, this software was found stable, easy to use and suitable for the application to the water supply corporations.展开更多
Combined heat and electricity operation with variable mass flow rates promotes flexibility,economy,and sustainability through synergies between electric power systems(EPSs)and district heating systems(DHSs).Such combi...Combined heat and electricity operation with variable mass flow rates promotes flexibility,economy,and sustainability through synergies between electric power systems(EPSs)and district heating systems(DHSs).Such combined operation presents a highly nonlinear and nonconvex optimization problem,mainly due to the bilinear terms in the heat flow model—that is,the product of the mass flow rate and the nodal temperature.Existing methods,such as nonlinear optimization,generalized Benders decomposition,and convex relaxation,still present challenges in achieving a satisfactory performance in terms of solution quality and computational efficiency.To resolve this problem,we herein first reformulate the district heating network model through an equivalent transformation and variable substitution.The reformulated model has only one set of nonconvex constraints with reduced bilinear terms,and the remaining constraints are linear.Such a reformulation not only ensures optimality,but also accelerates the solving process.To relax the remaining bilinear constraints,we then apply McCormick envelopes and obtain an objective lower bound of the reformulated model.To improve the quality of the McCormick relaxation,we employ a piecewise McCormick technique that partitions the domain of one of the variables of the bilinear terms into several disjoint regions in order to derive strengthened lower and upper bounds of the partitioned variables.We propose a heuristic tightening method to further constrict the strengthened bounds derived from the piecewise McCormick technique and recover a nearby feasible solution.Case studies show that,compared with the interior point method and the method implemented in a global bilinear solver,the proposed tightening McCormick method quickly solves the heat–electricity operation problem with an acceptable feasibility check and optimality.展开更多
基金supported by the National Natural Science Foundation of China(72071111,71801127,71671091)the NSFC and the UK Royal Society joint project(71811530338)+2 种基金the Special Postdoctoral Fund of China(2019TQ0150)the Fundamental Research Funds for the Central Universities of China(NC2019003)the Intelligence Introduction Base of the Ministry of Science and Technology(G20190010178)。
文摘Effectiveness evaluation of the joint operation system is an important basis for the demonstration and development of weapon equipment.With the consideration that existing models of system effectiveness evaluation seldom describe the structural relationship among equipment clearly as well as reflect the dynamic,the analog-to-digital converter-graphical evaluation and review technique(ADC-GERT)network parameter estimation model is proposed based on the ADC model and the joint operation system structure.Firstly,analysis of the joint operation system structure and operation process is conducted to build the GERT network,where equipment subsystems are nodes and activities are directed arches.Then the mission effectiveness of equipment subsystems is calculated by the ADC model.The probability transfer parameters are modified by the mission effectiveness of equipment subsystems based on the Bayesian theorem,with the ADC-GERT network parameter estimation model constructed.Finally,a case study is used to validate the efficiency and dynamic of the ADC-GERT network parameter estimation model.
文摘In the process industry, automation and process control systems are widely implemented, information integration is however far away from satisfactory. It remains a hard job for senior managers to make decisions based on the plant-wide real-time integrated information. This paper proposes a multi-layer information integration platform. In the data integration level, the standard for the exchange of product (STEP) and the extensible markup language (XML) are used to unify these data of the chemical process. In the model integration level, the models are integrated by using the neutral model repository and CAPE-OPEN. In the integration of process task, the common object request broker architecture (CORBA) is used as the communication mediator. The XML is taken as the data standard. A uniform information platform is thus constructed and realized. The proposed information integration platform is satisfactorily implemented to solve the Tennessee Eastman (TE) problem.
文摘A simple method for calculating the 3D coordinates of points on a micro object in a multi camera system is proposed. It simplifies the algorithms used in traditional computer vision system by eliminating the calculation of the CCD (charge coupled device) camera parameters and the relative position between cameras, and using solid geometry in the calculation procedures instead of the calculation of the complex matrixes. The algorithm was used in the research of generating a virtual magnified 3D image of a micro object to be operated in a micro operation system, and the satisfactory results were obtained. The application in a virtual tele operation system for a dexterous mechanical gripper is under test.
基金Foundation for U niversity Key Teacher bythe Ministry of Education and National Natural Science Founda-tion of China ( No.69875 0 0 4) and 863 High-Tech Plan ( No.2 0 0 1AA42 3 2 40 )
文摘Teleoperation system plays an important role in executing task under hazard environment. As the computer networks such as the Internet are being used as the communication channel of teleoperation system, varying time delay causes the overall system unstable and reduces the performance of transparency. This paper proposed twelve operation modes with different control schemes for teleoperation on the Internet with time delay. And an optimal operation mode with control scheme was specified for teleoperation with time delay, based on the tradeoff between passivity and transparency properties. It experimentally confirmed the validity of the proposed optimal mode and control scheme by using a simple one DOF master-slave manipulator system.
基金supported by National Natural Science Foundation of China(No.51877049).
文摘The increasing penetration of wind power poses challenges to the power grid operation and scheduling. Yet, if the uncertainty of wind power can be economically and effec tively managed on the source side, it can drive the power grids towards renewable-dominant future. In this paper, an en hanced scheduling strategy for wind farm−flexible load joint op eration system (WF-FLJOS) is proposed. The proposed strategy is designed to manage the uncertainty of wind power on the generation side when integrated into a large-scale power grid. Moreover, it can contribute to saving energy costs on the load side. Compared with the current wind farm operation rules, more stringent assessment requirements are put forward for wind power output accuracy, and the internal organization framework of WF-FLJOS is designed. For potential power vio lations of wind farms and flexible loads, the violation penalty mechanisms are developed to regulate the behavior of the par ticipants. The joint operation model of the WF-FLJOS is pro posed and the submission and tracking approach of the genera tion schedule for the wind farm is investigated. Numerical re sults indicate that the proposed strategy can not only improve the ability of the wind farm to track the generation schedule, but also consider the benefits of both the farm side and the load side. Meanwhile, the proposed strategy effectively reduces the schedule adjustment pressure on the main grid caused by the rolling correction mode of the intraday schedule for wind farms.
基金supported by a Horizontal Project on the Development of a Hybrid Energy Storage Simulation Model for Wind Power Based on an RT-LAB Simulation System(PH2023000190)the Inner Mongolia Natural Science Foundation Project and the Optimization of Exergy Efficiency of a Hybrid Energy Storage System with Crossover Control for Wind Power(2023JQ04).
文摘Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longer period.A multi-objective genetic algorithm(MOGA)and state of charge(SOC)region division for the batteries are introduced to solve the objective function and configuration of the system capacity,respectively.MATLAB/Simulink was used for simulation test.The optimization results show that for a 0.5 MW wind power and 0.5 MW photovoltaic system,with a combination of a 300 Ah lithium battery,a 200 Ah lead-acid battery,and a water storage tank,the proposed strategy reduces the system construction cost by approximately 18,000 yuan.Additionally,the cycle count of the electrochemical energy storage systemincreases from4515 to 4660,while the depth of discharge decreases from 55.37%to 53.65%,achieving shallow charging and discharging,thereby extending battery life and reducing grid voltage fluctuations significantly.The proposed strategy is a guide for stabilizing the grid connection of wind and solar power generation,capability allocation,and energy management of energy conservation systems.
文摘This paper focuses on AI intelligence as the fundamental direction to conduct research on information system operation and maintenance(O&M).Combining current AI-supported technologies in information system O&M,it proposes O&M strategies such as intelligent fault prediction and diagnosis,intelligent system performance optimization,intelligent system security protection,and adaptive system O&M implementation.Practical applications reveal that AI intelligence technology offers significant advantages in information system O&M,effectively addressing pain points of traditional O&M techniques,such as low fault prediction rates,slow repair speeds,poor security interception,and high labor costs.This substantially enhances the effectiveness of information system O&M.
文摘Digital twin shows broad application prospects in the aerospace field.This paper introduces a generalized satellite digital twin system in detail.With the innovative design concepts of modularization,generalization and modeling,on the one hand,the system has successfully achieved the reuse of software modules among different satellite models;on the other hand,it has achieved the reuse of software modules between the digital twin and the testing system,significantly improving the development efficiency of the digital twin system.The paper elaborates on the technical architecture and application fields of this digital twin system,and further prospects its future development.At the same time,through a real inorbit case,the engineering value of the digital twin system is strongly demonstrated.
基金Joint Innovation Program of Guangdong(Project No.:2023A0505020003)。
文摘The rapid expansion of photovoltaic(PV)deployment poses new challenges for large-scale and distributed maintenance,particularly in fishery-PV complementary plants where panels are deployed over water surfaces.This paper presents the design and implementation of an intelligent operation and maintenance(O&M)system that integrates a 3D holographic digital twin cloud platform with UAV-assisted inspection and localized cleaning.The proposed system supports multi-source data acquisition,including UAV imagery,infrared sensing,and DustIQ-based soiling monitoring,and provides real-time visualization of the PV plant through 1:13D reconstruction.UAVs are employed for both autonomous inspections,covering defects such as soiling,bird droppings,bypass diode faults,and panel disconnections and targeted cleaning in small water-covered areas.Field trials were conducted at Riyue and Chebu PV plants,with small-scale UAV cleaning validation in Chebu fish ponds.Results demonstrated that the system achieves efficient task scheduling,fault detection,and localized cleaning,thereby improving O&M efficiency,reducing costs,and enabling digitalized and intelligent management for large-scale PV stations.
基金supported by the National Natural Science Foundation of China(Grant Nos.42375062 and 42275158)the National Key Scientific and Technological Infrastructure project“Earth System Science Numerical Simulator Facility”(EarthLab)the Natural Science Foundation of Gansu Province(Grant No.22JR5RF1080)。
文摘It is fundamental and useful to investigate how deep learning forecasting models(DLMs)perform compared to operational oceanography forecast systems(OFSs).However,few studies have intercompared their performances using an identical reference.In this study,three physically reasonable DLMs are implemented for the forecasting of the sea surface temperature(SST),sea level anomaly(SLA),and sea surface velocity in the South China Sea.The DLMs are validated against both the testing dataset and the“OceanPredict”Class 4 dataset.Results show that the DLMs'RMSEs against the latter increase by 44%,245%,302%,and 109%for SST,SLA,current speed,and direction,respectively,compared to those against the former.Therefore,different references have significant influences on the validation,and it is necessary to use an identical and independent reference to intercompare the DLMs and OFSs.Against the Class 4 dataset,the DLMs present significantly better performance for SLA than the OFSs,and slightly better performances for other variables.The error patterns of the DLMs and OFSs show a high degree of similarity,which is reasonable from the viewpoint of predictability,facilitating further applications of the DLMs.For extreme events,the DLMs and OFSs both present large but similar forecast errors for SLA and current speed,while the DLMs are likely to give larger errors for SST and current direction.This study provides an evaluation of the forecast skills of commonly used DLMs and provides an example to objectively intercompare different DLMs.
基金supported by the National Key R&D Program of China(2022YFE0200400).
文摘The accurate selection of operational parameters is critical for ensuring the safety,efficiency,and automation of Tunnel Boring Machine(TBM)operations.This study proposes a similarity-based framework integrating model-based boring indexes(derived from rock fragmentation mechanisms)and Euclidean distance analysis to achieve real-time recommendations of TBM operational parameters.Key performance indicators-thrust(F),torque(T),and penetration(p)-were used to calculate three model-based boring indexes(a,b,k),which quantify dynamic rock fragmentation behavior.A dataset of 359 candidate samples,reflecting diverse geological conditions from the Yin-Chao water conveyance project in Inner Mongolia,China,was utilized to validate the framework.The system dynamically recommends parameters by matching real-time data with historical cases through standardized Euclidean distance,achieving high accuracy.Specifically,the mean absolute error(MAE)for rotation speed(n)was 0.10 r/min,corresponding to a mean absolute percentage error(MAPE)of 1.09%.For advance rate(v),the MAE was 3.4 mm/min,with a MAPE of 4.50%.The predicted thrust(F)and torque(T)values exhibited strong agreement with field measurements,with MAEs of 270 kN and 178 kN∙m,respectively.Field applications demonstrated a 30%reduction in parameter adjustment time compared to empirical methods.This work provides a robust solution for real-time TBM control,advancing intelligent tunneling in complex geological environments.
基金supported by the National Key Research&Development Program of China(2021YFB3301100)the National Natural Science Foundation of China(52004014)the Fundamental Research Funds for the Central Universities(ZY2406).
文摘This paper proposed a new systematic approach-functional evidential reasoning model(FERM) for exploring hazardous chemical operational accidents under uncertainty. First, FERM was introduced to identify various causal factors and their performance changes in hazardous chemical operational accidents, along with determining the functional failure link relationships. Subsequently, FERM was employed to elucidate both qualitative and quantitative operational accident information within a unified framework, which could be regarded as the input of information fusion to obtain the fuzzy belief distribution of each cause factor. Finally, the derived risk values of the causal factors were ranked while constructing multi-level accident causation chains to unveil the weak links in system functionality and the primary roots of operational accidents. Using the specific case of the “1·15” major explosion and fire accident at Liaoning Panjin Haoye Chemical Co., Ltd., seven causal factors and their corresponding performance changes were identified. Additionally, five accident causation chains were uncovered based on the fuzzy joint distribution of the functional assessment level(FAL) and reliability distribution(RD),revealing an overall increase in risk along the accident evolution path. The research findings demonstrated that FERM enabled the effective characterization, rational quantification and accurate analysis of the inherent uncertainties in hazardous chemical operational accident risks from a systemic perspective.
基金Supported by the Science and Technology Program of Guizhou Province(Grant No.QKHJC QN[2025]362)the National Natural Science Foundation of China(Grant No.12361005).
文摘Loday introduced di-associative algebras and tri-associative algebras motivated by periodicity phenomena in algebraic K-theory.The purpose of this paper is to study the splittings of operations on di-associative algebras and tri-associative algebras.We introduce the notion of a quad-dendriform algebra,which is a splitting of a di-associative algebra.We show that a relative averaging operator on dendriform algebras gives rise to a quad-dendriform algebra.Furthermore,we introduce the notion of six-dendriform algebras,which are splittings of the tri-associative algebras,and demonstrate that homomorphic relative averaging operators induce six-dendriform algebras.
基金The National Key Technology R&D Program of Chinaduring the 11th Five-Year Plan Period(No.2008BAJ12B04)China Postdoctoral Science Foundation(No.20090461050)+1 种基金the Project of Researchand Development of Ministry of Housing and Urban-Rural Development ofChina(No.2008-K1-26)the New Century Talent Project of Yangzhou University for Excellent Young Backbone Teacher(2008)
文摘In order to investigate the alternate operation characteristics of a solar-ground source heat pump system（SGSHPS）,various alternate operation modes are put forward and defined.A two-dimensional mathematical model with freezing/melting phase changes is developed for the heat transfer analysis of the soil.Based on the numerical solution of the model,the variation trends of underground soil temperature of the SGSHPS operated in various alternate operation modes are discussed.The results indicate that,for the day-night and short-time interval alternate operation modes without solar energy,the operation time fraction of a solar heat source should be confined to from 50% to 58% when operated in an alternate period of 24 h.Meanwhile,the disadvantages of a natural resumption of soil temperature can be overcome effectively by solar energy filling,and an optimal operation effect can be achieved by integrating the mode of solar energy filling with other alternate modes.In addition,the accuracy of the presented model is verified by the experimental data of borehole wall temperatures.The conclusions can provide a reference for the optimization operation of the SGSHPS.
基金The National High Technology Research and Development Program of China(863Program)(No.2006AA04Z416)
文摘An output-only modal identification method by a combination use of the peak-picking method and the cross spectrum methods are presented. Meanwhile, a novel mode shape optimum method of the deck is proposed. The methods are applied to the operational modal identification system of the Runyang Suspension Bridge, which can be used to obtain the modal parameters of the bridge from out-only data sets collected by its structural health monitoring system （SHMS）. As an example, the vibration response data of the deck, cable and tower recorded during typhoon Matsa excitation are used to illustrate the program application. Some of the modal frequencies observed from deck vibration responses are also found in the vibration responses of the cable and the tower. The results show that some modal shapes of the deck are strongly coupled with the cable and the tower. By comparing the identification results from the operational modal system with those from field measurements, a good agreement between them is achieved, but some modal frequencies identified from the operational modal identification system （OMIS）, such as L1 and L2, obviously decrease compared with those from the field measurements.
文摘Basing on a viewpoint of all sided water producing system,a comprehensive analysis of the operation status and the relationship between each working unit in water producing system,including coagulation,sedimentation and filtration etc.was made.By investigating the influence of backwashing consumption,the amount of sludge ejected from sedimentation tank and coagulant ratio upon the cost,the cost effective function of the system was presented.Afterwards,the solution was found out and the corresponding computer program was developed.When applied with real world data,it proved that this method significantly reduced the water producing cost.
文摘This article summarizes the theoretical results in Laboratory economy, defines the model of the laboratory economic of schools and enterprises to build, analyzes its organizational model and elaborates its operational mechanism, so as to provide a reference for School-enterprise cooperation, laboratory-economic development and innovation performance of Laboratory economy established by university and enterprise.
文摘It is not only meteorological problems for the medium-range numerical weather prediction (NWP) research to be in operation,but also engineering and technological problems.Here we gener- ally described the results of research,engineering construction,operation information and testing,in the course of set-up of medium-range NWP operation system in the China National Meteorological Center.
文摘In this research, LINGO is used successfully to solve the water supply system′s optimal operation model. Firstly, the language of LINGO and the using method were studied intensively, on the basis of which the model was transformed to LINGO form and solved successfully. Secondly, the research on the interface between LINGO and the popular office software was made. The optimization software was developed, which had Excel as the workspace and LINGO as the core of computation. Through practice, this software was found stable, easy to use and suitable for the application to the water supply corporations.
基金This work was supported by the Science and Technology Program of State Grid Corporation of China(522300190008).
文摘Combined heat and electricity operation with variable mass flow rates promotes flexibility,economy,and sustainability through synergies between electric power systems(EPSs)and district heating systems(DHSs).Such combined operation presents a highly nonlinear and nonconvex optimization problem,mainly due to the bilinear terms in the heat flow model—that is,the product of the mass flow rate and the nodal temperature.Existing methods,such as nonlinear optimization,generalized Benders decomposition,and convex relaxation,still present challenges in achieving a satisfactory performance in terms of solution quality and computational efficiency.To resolve this problem,we herein first reformulate the district heating network model through an equivalent transformation and variable substitution.The reformulated model has only one set of nonconvex constraints with reduced bilinear terms,and the remaining constraints are linear.Such a reformulation not only ensures optimality,but also accelerates the solving process.To relax the remaining bilinear constraints,we then apply McCormick envelopes and obtain an objective lower bound of the reformulated model.To improve the quality of the McCormick relaxation,we employ a piecewise McCormick technique that partitions the domain of one of the variables of the bilinear terms into several disjoint regions in order to derive strengthened lower and upper bounds of the partitioned variables.We propose a heuristic tightening method to further constrict the strengthened bounds derived from the piecewise McCormick technique and recover a nearby feasible solution.Case studies show that,compared with the interior point method and the method implemented in a global bilinear solver,the proposed tightening McCormick method quickly solves the heat–electricity operation problem with an acceptable feasibility check and optimality.
