The accurate simulation and prediction of runoff in alpine glaciated watersheds is of increasing importance for the comprehensive management and utilization of water resources.In this study,long shortterm memory(LSTM)...The accurate simulation and prediction of runoff in alpine glaciated watersheds is of increasing importance for the comprehensive management and utilization of water resources.In this study,long shortterm memory(LSTM),a state-of-the-art artificial neural network algorithm,is applied to simulate the daily discharge of two data-sparse glaciated watersheds in the Tianshan Mountains in Central Asia.Two other classic machine learning methods,namely extreme gradient boosting(XGBoost)and support vector regression(SVR),along with a distributed hydrological model(Soil and Water Assessment Tool(SWAT)and an extended SWAT model(SWAT_Glacier)are also employed for comparison.This paper aims to provide an efficient and reliable method for simulating discharge in glaciated alpine regions that have insufficient observed meteorological data.The two typical basins in this study are the main tributaries(the Kumaric and Toxkan rivers)of the Aksu River in the south Tianshan Mountains,which are dominated by snow and glacier meltwater and precipitation.Our comparative analysis indicates that simulations from the LSTM shows the best agreement with the observations.The performance metrics Nash-Sutcliffe efficiency coefficient(NS)and correlation coefficient(R^(2))of LSTM are higher than 0.90 in both the training and testing periods in the Kumaric River Basin,and NS and R^(2) are also higher than 0.70 in the Toxkan River Basin.Compared to classic machine learning algorithms,LSTM shows significant advantages over most evaluating indices.XGBoost also has high NS value in the training period,but is prone to overfitting the discharge.Compared with the widely used hydrological models,LSTM has advantages in predicting accuracy,despite having fewer data inputs.Moreover,LSTM only requires meteorological data rather than physical characteristics of underlying data.As an extension of SWAT,the SWAT_Glacier model shows good adaptability in discharge simulation,outperforming the original SWAT model,but at the cost of increasing the complexity of the model.Compared with the oftentimes complex semi-distributed physical hydrological models,the LSTM method not only eliminates the tedious calibration process of hydrological parameters,but also significantly reduces the calculation time and costs.Overall,LSTM shows immense promise in dealing with scarce meteorological data in glaciated catchments.展开更多
The spread of fire and smoke during a fire incident plays a crucial role in rescuing people from the burning building. So it is important for the decision makers (the head of rescue staff) to get a prediction about th...The spread of fire and smoke during a fire incident plays a crucial role in rescuing people from the burning building. So it is important for the decision makers (the head of rescue staff) to get a prediction about the spread of fire inside the building through computational techniques like numerical fire simulations. But these techniques require advanced mathematical knowledge and are very time consuming. This paper presents a new method which employs a set of pre-simulated and model-based scenarios to find the closest one to the real fire and present its results to the decision makers. For this purpose, we shift the performance consuming numerical fire simulations into a former phase by integration of these simulations into the planning process of the building. This is realized by enhancing the methods of Building Information Modeling (BIM). To provide the fire simulation results during a real case, our new concept includes a scenario database where all simulated fire scenarios will be collected. In a real case, a special search algorithm will go through this database to find the closest pre-simulated fire scenario to the real fire on the basis of reported information from the burning building.展开更多
In order to estimate the readiness, sustainability and support capability of the operational unit, an support simulation concept model of the military equipment is given as viewed from the system engineering modeling ...In order to estimate the readiness, sustainability and support capability of the operational unit, an support simulation concept model of the military equipment is given as viewed from the system engineering modeling and simulation. Simulation test of military aircraft is analyzed in detail, it is composed of the operational mission, function maintenance process and resource modeling.展开更多
With the expansion of the office building area,the energy consumption of office buildings is growing.High⁃performance building design contributes to energy saving and the development of green buildings.However,there i...With the expansion of the office building area,the energy consumption of office buildings is growing.High⁃performance building design contributes to energy saving and the development of green buildings.However,there is a lack of high⁃performance building tools and the workflow is often time⁃consuming.The building performance simulation,multiple objective optimizations,and the decision support model are the new approaches of high⁃performance building design.This paper proposes a newly developed decision support model,a high⁃performance building decision model named HPBuildingDSM,which integrates the building performance simulation,building performance multiple objective optimizations,building performance sampling,and parameter sensitivity analysis to design high⁃performance office buildings.In this research,the HPBuildingDSM was operated to search for the desirable office building design results with low⁃energy and high⁃quality daylighting performances.The simulated results had better daylighting performance and lower energy consumption,whose UDI100-2000 was 37.94%and annual energy consumption performance was 76.28 kWh/(m2·a),indicating a better building performance than the optimized results in the previous case study.展开更多
Fully mechanized mining with large mining height(FMMLMH)is widely used in thick coal seam mining face for its higher recovery ratio,especially where the thickness is less than 7.0 m.However,because of the great mining...Fully mechanized mining with large mining height(FMMLMH)is widely used in thick coal seam mining face for its higher recovery ratio,especially where the thickness is less than 7.0 m.However,because of the great mining height and intense rock pressure,the coal wall rib spalling,roof falling and the instability of support occur more likely in FMMLMH working face,and the above three types of disasters interact with each other with complicated relationships.In order to get the relationship between each two of coal wall,roof,floor and support,and reduce the occurrence probability of the three types of disasters,we established the system dynamics(SD)model of the support-surrounding rock system which is composed of"coal wall-roof-floor-support"(CW-R-F-S)in a FMMLMH working face based on the condition of No.15104 working face in Sijiazhuang coal mine.With the software of Vensim,we also simulated the interaction process between each two factors of roof,floor,coal wall and the support.The results show that the SD model of"CW-R-F-S"system can reveal the complicated and interactive relationship clearly between the support and surrounding rock in the FMMLMH working face.By increasing the advancing speed of working face,the support resistance or the length of support guard,or by decreasing the tipto-face distance,the stability of"CW-R-F-S"system will be higher and the happening probability of the disasters such as coal wall rib spalling,roof falling or the instability of support will be lower.These research findings have been testified in field application in No.15104 working face,which can provide a new approach for researching the interaction relationship of support and surrounding rock.展开更多
The modeling and simulation(M&S)architecture describes and defines the relationship between the different parts of a simulation.The simulation system architecture and simulation support platform architecture are d...The modeling and simulation(M&S)architecture describes and defines the relationship between the different parts of a simulation.The simulation system architecture and simulation support platform architecture are discussed separately.The simulation support platform architecture consists of the management layer,the resource layer,the communication layer,the application layer and the infrastructure layer.The best way is to design and realize the M&S collaborative environment for simulation support platform in the resource-communication-application three-dimension space.展开更多
The simulation-based decision support system (SBDSS) is designed to achieve a highlevel of performance, flexibility and adaptability, in response to meet the special needs of productionand logistics management during ...The simulation-based decision support system (SBDSS) is designed to achieve a highlevel of performance, flexibility and adaptability, in response to meet the special needs of productionand logistics management during the economic system reform era in China. It consists two subsys-tems: the object library modeler (OLM) and the simulation engine and its manager (SEM). UsingSBDSS the decision makers can work out their optimal production choice under certain circumstancesthrough scenario simulations. And they can test a set of virtual organizations reflecting systems re-form before a real reorganization has been taken, as well as perform a virtual manufacturing processfor a new product design (Copyright @ 1998 IFAC).展开更多
Based on simulation experiments of a number of scientific research items, the latest progress of experiment method and test technique about equivalent material simulation are introduced. The bevelopment of experiment ...Based on simulation experiments of a number of scientific research items, the latest progress of experiment method and test technique about equivalent material simulation are introduced. The bevelopment of experiment technique makes analogy simulation evolve into quantitative research about support-surrounding rock relationship from qualitative experiment.From this, large scale stereoscopic simulation experiment is developed, which has never appeared in underground pressure research in China. The present mold specification is 3 - 6 m×2. 0 m ×1. 5 m.展开更多
This paper reports an aspiration-directed, model-based decision support system (AMDSS) integrated with a knowledge-based simulation system. The system is designed to study China's mid-range economic development st...This paper reports an aspiration-directed, model-based decision support system (AMDSS) integrated with a knowledge-based simulation system. The system is designed to study China's mid-range economic development strategy. The capacity of the system is enhanced by the knowledge-based component which provides a knowledge-based simulation environment for model management. Currently the system has passed the stage of prototype and achieves its implementation capacity. The paper first presents the mathematical aspects of decision making including aspiration-directed decision making, then discusses the architecture of the system. The purpose of the paper is to provide insights into how such an integrated system could provide decision support for complex decision analysis.展开更多
Ground support systems are commonly used to mitigate the potential consequences of rockburst in burst prone mines.To assess the capacity of ground support systems when subjected to dynamic loading,simulated rockburst ...Ground support systems are commonly used to mitigate the potential consequences of rockburst in burst prone mines.To assess the capacity of ground support systems when subjected to dynamic loading,simulated rockburst tests using blasting were conducted at the Kiruna Mine.In this study,a numerical simulation for one of the field tests was conducted using the LS-DYNA code to investigate the dynamic response of the ground support systems including shotcrete and rockbolts.The numerical results showed a similar particle vibration pattern and a crack pattern to those of the field measurements.The effects of the detonator position and the charge configuration on the dynamic response of ground support systems are also discussed.Numerical results indicated that the peak particle vibrations on the tested panel increase along the direction of detonation propagation.It is difficult to use different charge concentrations in one borehole to investigate the effect of different dynamic loads on the dynamic response of support systems.Numerical results also indicated that 2D numerical modeling for simulated rockburst experiments could overestimate the dynamic response of ground support systems.展开更多
The paper is an analysis of applicability of system dynamics to description of airlines′ economic operation. It is the first attempt to use the theory and approaches of system dynamics to build a dynamic economic ope...The paper is an analysis of applicability of system dynamics to description of airlines′ economic operation. It is the first attempt to use the theory and approaches of system dynamics to build a dynamic economic operation model for airlines. The paper introduces modeling design, basic model structure and content. A computer simulation of benefit analysis is given in the case of a given airline of China. Whereupon the outcome proves that it is successful using system dynamics theory and approaches to describe non linear, multivariable, dynamic, multiple\|feedback, complex economic systems, as in airlines. The model offers a powerful support to decision makers, greatly upgrading the systematicness and foreseeability of enterprise management. The theory and approaches, advanced in the paper, is also applicable to enterprises in other sectors.展开更多
基金supported by the National Natural Science Foundation of China(U1903208,41630859,42071046)。
文摘The accurate simulation and prediction of runoff in alpine glaciated watersheds is of increasing importance for the comprehensive management and utilization of water resources.In this study,long shortterm memory(LSTM),a state-of-the-art artificial neural network algorithm,is applied to simulate the daily discharge of two data-sparse glaciated watersheds in the Tianshan Mountains in Central Asia.Two other classic machine learning methods,namely extreme gradient boosting(XGBoost)and support vector regression(SVR),along with a distributed hydrological model(Soil and Water Assessment Tool(SWAT)and an extended SWAT model(SWAT_Glacier)are also employed for comparison.This paper aims to provide an efficient and reliable method for simulating discharge in glaciated alpine regions that have insufficient observed meteorological data.The two typical basins in this study are the main tributaries(the Kumaric and Toxkan rivers)of the Aksu River in the south Tianshan Mountains,which are dominated by snow and glacier meltwater and precipitation.Our comparative analysis indicates that simulations from the LSTM shows the best agreement with the observations.The performance metrics Nash-Sutcliffe efficiency coefficient(NS)and correlation coefficient(R^(2))of LSTM are higher than 0.90 in both the training and testing periods in the Kumaric River Basin,and NS and R^(2) are also higher than 0.70 in the Toxkan River Basin.Compared to classic machine learning algorithms,LSTM shows significant advantages over most evaluating indices.XGBoost also has high NS value in the training period,but is prone to overfitting the discharge.Compared with the widely used hydrological models,LSTM has advantages in predicting accuracy,despite having fewer data inputs.Moreover,LSTM only requires meteorological data rather than physical characteristics of underlying data.As an extension of SWAT,the SWAT_Glacier model shows good adaptability in discharge simulation,outperforming the original SWAT model,but at the cost of increasing the complexity of the model.Compared with the oftentimes complex semi-distributed physical hydrological models,the LSTM method not only eliminates the tedious calibration process of hydrological parameters,but also significantly reduces the calculation time and costs.Overall,LSTM shows immense promise in dealing with scarce meteorological data in glaciated catchments.
文摘The spread of fire and smoke during a fire incident plays a crucial role in rescuing people from the burning building. So it is important for the decision makers (the head of rescue staff) to get a prediction about the spread of fire inside the building through computational techniques like numerical fire simulations. But these techniques require advanced mathematical knowledge and are very time consuming. This paper presents a new method which employs a set of pre-simulated and model-based scenarios to find the closest one to the real fire and present its results to the decision makers. For this purpose, we shift the performance consuming numerical fire simulations into a former phase by integration of these simulations into the planning process of the building. This is realized by enhancing the methods of Building Information Modeling (BIM). To provide the fire simulation results during a real case, our new concept includes a scenario database where all simulated fire scenarios will be collected. In a real case, a special search algorithm will go through this database to find the closest pre-simulated fire scenario to the real fire on the basis of reported information from the burning building.
文摘In order to estimate the readiness, sustainability and support capability of the operational unit, an support simulation concept model of the military equipment is given as viewed from the system engineering modeling and simulation. Simulation test of military aircraft is analyzed in detail, it is composed of the operational mission, function maintenance process and resource modeling.
文摘With the expansion of the office building area,the energy consumption of office buildings is growing.High⁃performance building design contributes to energy saving and the development of green buildings.However,there is a lack of high⁃performance building tools and the workflow is often time⁃consuming.The building performance simulation,multiple objective optimizations,and the decision support model are the new approaches of high⁃performance building design.This paper proposes a newly developed decision support model,a high⁃performance building decision model named HPBuildingDSM,which integrates the building performance simulation,building performance multiple objective optimizations,building performance sampling,and parameter sensitivity analysis to design high⁃performance office buildings.In this research,the HPBuildingDSM was operated to search for the desirable office building design results with low⁃energy and high⁃quality daylighting performances.The simulated results had better daylighting performance and lower energy consumption,whose UDI100-2000 was 37.94%and annual energy consumption performance was 76.28 kWh/(m2·a),indicating a better building performance than the optimized results in the previous case study.
基金Financial support for this work,provided by the Priority Academic Program Development of Jiangsu Higher Education Institutions(No.SZBF2011-6-B35)the Research Fund for the Doctoral Program of Higher Education of China(No.20120095120017)the National High Technology Research and Development Program of China(No.2012AA062101)
文摘Fully mechanized mining with large mining height(FMMLMH)is widely used in thick coal seam mining face for its higher recovery ratio,especially where the thickness is less than 7.0 m.However,because of the great mining height and intense rock pressure,the coal wall rib spalling,roof falling and the instability of support occur more likely in FMMLMH working face,and the above three types of disasters interact with each other with complicated relationships.In order to get the relationship between each two of coal wall,roof,floor and support,and reduce the occurrence probability of the three types of disasters,we established the system dynamics(SD)model of the support-surrounding rock system which is composed of"coal wall-roof-floor-support"(CW-R-F-S)in a FMMLMH working face based on the condition of No.15104 working face in Sijiazhuang coal mine.With the software of Vensim,we also simulated the interaction process between each two factors of roof,floor,coal wall and the support.The results show that the SD model of"CW-R-F-S"system can reveal the complicated and interactive relationship clearly between the support and surrounding rock in the FMMLMH working face.By increasing the advancing speed of working face,the support resistance or the length of support guard,or by decreasing the tipto-face distance,the stability of"CW-R-F-S"system will be higher and the happening probability of the disasters such as coal wall rib spalling,roof falling or the instability of support will be lower.These research findings have been testified in field application in No.15104 working face,which can provide a new approach for researching the interaction relationship of support and surrounding rock.
基金supported by the National Natural Science Foundation of China(Grant No.60404016).
文摘The modeling and simulation(M&S)architecture describes and defines the relationship between the different parts of a simulation.The simulation system architecture and simulation support platform architecture are discussed separately.The simulation support platform architecture consists of the management layer,the resource layer,the communication layer,the application layer and the infrastructure layer.The best way is to design and realize the M&S collaborative environment for simulation support platform in the resource-communication-application three-dimension space.
文摘The simulation-based decision support system (SBDSS) is designed to achieve a highlevel of performance, flexibility and adaptability, in response to meet the special needs of productionand logistics management during the economic system reform era in China. It consists two subsys-tems: the object library modeler (OLM) and the simulation engine and its manager (SEM). UsingSBDSS the decision makers can work out their optimal production choice under certain circumstancesthrough scenario simulations. And they can test a set of virtual organizations reflecting systems re-form before a real reorganization has been taken, as well as perform a virtual manufacturing processfor a new product design (Copyright @ 1998 IFAC).
文摘Based on simulation experiments of a number of scientific research items, the latest progress of experiment method and test technique about equivalent material simulation are introduced. The bevelopment of experiment technique makes analogy simulation evolve into quantitative research about support-surrounding rock relationship from qualitative experiment.From this, large scale stereoscopic simulation experiment is developed, which has never appeared in underground pressure research in China. The present mold specification is 3 - 6 m×2. 0 m ×1. 5 m.
文摘This paper reports an aspiration-directed, model-based decision support system (AMDSS) integrated with a knowledge-based simulation system. The system is designed to study China's mid-range economic development strategy. The capacity of the system is enhanced by the knowledge-based component which provides a knowledge-based simulation environment for model management. Currently the system has passed the stage of prototype and achieves its implementation capacity. The paper first presents the mathematical aspects of decision making including aspiration-directed decision making, then discusses the architecture of the system. The purpose of the paper is to provide insights into how such an integrated system could provide decision support for complex decision analysis.
基金supported by the Centre of Advanced Mining&Metallurgy(CAMM2)at Lulea University of Technologythe support from the project of SLIM funded by the European Union’s Horizon 2020 research and innovation program under grant agreement N°730294.
文摘Ground support systems are commonly used to mitigate the potential consequences of rockburst in burst prone mines.To assess the capacity of ground support systems when subjected to dynamic loading,simulated rockburst tests using blasting were conducted at the Kiruna Mine.In this study,a numerical simulation for one of the field tests was conducted using the LS-DYNA code to investigate the dynamic response of the ground support systems including shotcrete and rockbolts.The numerical results showed a similar particle vibration pattern and a crack pattern to those of the field measurements.The effects of the detonator position and the charge configuration on the dynamic response of ground support systems are also discussed.Numerical results indicated that the peak particle vibrations on the tested panel increase along the direction of detonation propagation.It is difficult to use different charge concentrations in one borehole to investigate the effect of different dynamic loads on the dynamic response of support systems.Numerical results also indicated that 2D numerical modeling for simulated rockburst experiments could overestimate the dynamic response of ground support systems.
文摘The paper is an analysis of applicability of system dynamics to description of airlines′ economic operation. It is the first attempt to use the theory and approaches of system dynamics to build a dynamic economic operation model for airlines. The paper introduces modeling design, basic model structure and content. A computer simulation of benefit analysis is given in the case of a given airline of China. Whereupon the outcome proves that it is successful using system dynamics theory and approaches to describe non linear, multivariable, dynamic, multiple\|feedback, complex economic systems, as in airlines. The model offers a powerful support to decision makers, greatly upgrading the systematicness and foreseeability of enterprise management. The theory and approaches, advanced in the paper, is also applicable to enterprises in other sectors.