Based on computer graphics principle, technology and 3D graphics software, this paper deals with the 3D part design, assembly and animation of shearer in longwall integrated mechanized coal mining. The matixes of kine...Based on computer graphics principle, technology and 3D graphics software, this paper deals with the 3D part design, assembly and animation of shearer in longwall integrated mechanized coal mining. The matixes of kinetic and geometry relationships and 3 dimension space coordinate systems are built for the cut drums, arms and shearer body. The methods of 3D modeling, dynamic simulation and relative technique problems are discussed.展开更多
In this article,we introduce a nonlinear Caputo-type snakebite envenoming model with memory.The well-known Caputo fractional derivative is used to generalize the previously presented integer-order model into a fractio...In this article,we introduce a nonlinear Caputo-type snakebite envenoming model with memory.The well-known Caputo fractional derivative is used to generalize the previously presented integer-order model into a fractionalorder sense.The numerical solution of the model is derived from a novel implementation of a finite-difference predictor-corrector(L1-PC)scheme with error estimation and stability analysis.The proof of the existence and positivity of the solution is given by using the fixed point theory.From the necessary simulations,we justify that the first-time implementation of the proposedmethod on an epidemicmodel shows that the scheme is fully suitable and time-efficient for solving epidemic models.This work aims to show the novel application of the given scheme as well as to check how the proposed snakebite envenoming model behaves in the presence of the Caputo fractional derivative,including memory effects.展开更多
The APEXeditor, an Excel-based tool has been developed using the Visual Basic for Applications (VBA) to provide a graphical user interface (GUI) to the Agricultural Policy Environmental eXtender (APEX) model. APEX, in...The APEXeditor, an Excel-based tool has been developed using the Visual Basic for Applications (VBA) to provide a graphical user interface (GUI) to the Agricultural Policy Environmental eXtender (APEX) model. APEX, in its native form, requires users to edit text files for modifying input files;therefore a GUI interface can aid users in modification of these files and reduce errors. Microsoft Excel is a popular spreadsheet program that has the largest user base among scientists and researchers, thus providing a relatively common platform in which stages the tool. The APEXeditor requires minimal additional learning to operate the tool for those who already have basic level of knowledge in Excel. The user can load APEX input files into the spreadsheet tool and the GUI offers meta information and provides functions to edit, write, and run the APEX model. Ultimately, the APEXeditor substitutes existing GUI programs such as WinAPEX or ArcAPEX that require installation or additional licensing. A series of scripts were developed as a back-end engine that automates data formatting and editing of linked APEX input ASCII files including database libraries. The simple architecture of the tool helps users maintain the quality of the data and allows error-free editing of APEX model inputs to characterize the system under study. This tool is suitable for all kinds of applications and has been successfully used for the creation of APEX model runs in numerous studies.展开更多
随着国际海事卫星通信系统(international maritime satellite communication system,INMARSAT)的不断发展,卫星地面站(satellite earth station,SES)的可用性评估具有重要意义。首先选取可靠性、维修性和保障性为指标,构建可靠性、维...随着国际海事卫星通信系统(international maritime satellite communication system,INMARSAT)的不断发展,卫星地面站(satellite earth station,SES)的可用性评估具有重要意义。首先选取可靠性、维修性和保障性为指标,构建可靠性、维修性与保障性(reliability,maintainability and supportability,RMS)模型进行SES可用性评估;其次,以SES设备为研究对象,根据马尔可夫链得到设备有效性概率,并进一步推导出系统可靠性;然后,建立排队图解协调技术(queue-graphical evaluation and review technique,Q-GERT)网络以描述SES设备的维修保障过程,并基于AnyLogic软件进行建模仿真;最后,通过算例进行应用研究,基于RMS模型进行SES可用性评估,验证了该模型和评估方法的有效性与实用性。展开更多
This paper presents the design and implementation of an integrated application program called ArcFVS that links the Forest Vegetation Simulator (FVS) and a Geographic Information System (GIS) to realize spatial select...This paper presents the design and implementation of an integrated application program called ArcFVS that links the Forest Vegetation Simulator (FVS) and a Geographic Information System (GIS) to realize spatial selection of input files and graphic display of modeling output. Data for testing and running the model came from the U.S. Forest Service's Forest Inventory and Analysis (FIA) Database and were also collected in field surveys in north-central Indiana. ArcFVS 1.0 is designed using the ArcGIS software from the Environmental Systems Research Institute (ESRI) and the Visual Basic for Applications (VBA) programming environment to manipulate ESRI's ArcObjects. The resulting product offers custom functions as commands in a new menu or as tools on a new toolbar. They are used to: select spatially or by attribute the forest plots to be projected by FVS, create the FVS input files for the selected plots and display in a geospatial environment different types of FVS output (text output files, tables with variables of interest and visualization image files). Advantages of ArcFVS 1.0 include the new GIS capabilities, enhanced format translation functions and the standardized programming environment.展开更多
文摘Based on computer graphics principle, technology and 3D graphics software, this paper deals with the 3D part design, assembly and animation of shearer in longwall integrated mechanized coal mining. The matixes of kinetic and geometry relationships and 3 dimension space coordinate systems are built for the cut drums, arms and shearer body. The methods of 3D modeling, dynamic simulation and relative technique problems are discussed.
文摘In this article,we introduce a nonlinear Caputo-type snakebite envenoming model with memory.The well-known Caputo fractional derivative is used to generalize the previously presented integer-order model into a fractionalorder sense.The numerical solution of the model is derived from a novel implementation of a finite-difference predictor-corrector(L1-PC)scheme with error estimation and stability analysis.The proof of the existence and positivity of the solution is given by using the fixed point theory.From the necessary simulations,we justify that the first-time implementation of the proposedmethod on an epidemicmodel shows that the scheme is fully suitable and time-efficient for solving epidemic models.This work aims to show the novel application of the given scheme as well as to check how the proposed snakebite envenoming model behaves in the presence of the Caputo fractional derivative,including memory effects.
文摘The APEXeditor, an Excel-based tool has been developed using the Visual Basic for Applications (VBA) to provide a graphical user interface (GUI) to the Agricultural Policy Environmental eXtender (APEX) model. APEX, in its native form, requires users to edit text files for modifying input files;therefore a GUI interface can aid users in modification of these files and reduce errors. Microsoft Excel is a popular spreadsheet program that has the largest user base among scientists and researchers, thus providing a relatively common platform in which stages the tool. The APEXeditor requires minimal additional learning to operate the tool for those who already have basic level of knowledge in Excel. The user can load APEX input files into the spreadsheet tool and the GUI offers meta information and provides functions to edit, write, and run the APEX model. Ultimately, the APEXeditor substitutes existing GUI programs such as WinAPEX or ArcAPEX that require installation or additional licensing. A series of scripts were developed as a back-end engine that automates data formatting and editing of linked APEX input ASCII files including database libraries. The simple architecture of the tool helps users maintain the quality of the data and allows error-free editing of APEX model inputs to characterize the system under study. This tool is suitable for all kinds of applications and has been successfully used for the creation of APEX model runs in numerous studies.
文摘随着国际海事卫星通信系统(international maritime satellite communication system,INMARSAT)的不断发展,卫星地面站(satellite earth station,SES)的可用性评估具有重要意义。首先选取可靠性、维修性和保障性为指标,构建可靠性、维修性与保障性(reliability,maintainability and supportability,RMS)模型进行SES可用性评估;其次,以SES设备为研究对象,根据马尔可夫链得到设备有效性概率,并进一步推导出系统可靠性;然后,建立排队图解协调技术(queue-graphical evaluation and review technique,Q-GERT)网络以描述SES设备的维修保障过程,并基于AnyLogic软件进行建模仿真;最后,通过算例进行应用研究,基于RMS模型进行SES可用性评估,验证了该模型和评估方法的有效性与实用性。
文摘This paper presents the design and implementation of an integrated application program called ArcFVS that links the Forest Vegetation Simulator (FVS) and a Geographic Information System (GIS) to realize spatial selection of input files and graphic display of modeling output. Data for testing and running the model came from the U.S. Forest Service's Forest Inventory and Analysis (FIA) Database and were also collected in field surveys in north-central Indiana. ArcFVS 1.0 is designed using the ArcGIS software from the Environmental Systems Research Institute (ESRI) and the Visual Basic for Applications (VBA) programming environment to manipulate ESRI's ArcObjects. The resulting product offers custom functions as commands in a new menu or as tools on a new toolbar. They are used to: select spatially or by attribute the forest plots to be projected by FVS, create the FVS input files for the selected plots and display in a geospatial environment different types of FVS output (text output files, tables with variables of interest and visualization image files). Advantages of ArcFVS 1.0 include the new GIS capabilities, enhanced format translation functions and the standardized programming environment.
