In order to grasp the evolution of flight conflict amount accurately and to forecast the amount, chaos in flight conflicts is studied. Firstly, a fault tree of flight conflicts is established based on the man-machine-...In order to grasp the evolution of flight conflict amount accurately and to forecast the amount, chaos in flight conflicts is studied. Firstly, a fault tree of flight conflicts is established based on the man-machine-environ- ment system engineering theory. The chaotic characteristics of flight conflict are analyzed from the qualitative point of view. Secondly, an improved chaotic algorithm for the largest Lyapunov exponent is proposed based on the small-data method and the wavelet de-noising theory. Chaos in flight conflict time series is identified by the improved chaotic algorithm from the quantitative point of view. Finally, a case study by the chaos forecasting al- gorithm is performed and the results are evaluated by the gray error checking : Correlative value of posterior error is 0. 220 9〈0. 35, and micro-error probability is 0. 985 3〉0.95. Such results show the chaos forecasting algo- rithm is effective, thus it is feasible to analyze and forecast flight conflict by chaotic theory.展开更多
The farming-pastoral zone of northern China plays a dual role in ecological conditions and production and occupies an important position in the national economy. In this paper, the methodology of system engineering is...The farming-pastoral zone of northern China plays a dual role in ecological conditions and production and occupies an important position in the national economy. In this paper, the methodology of system engineering is introduced to construct and optimize an eco-productive paradigm system for the typical areas of the farming-pastoral zone. The system was constructed in the following steps: (1) design the framework of the paradigm system based on the data of physical site characteristics, biocommunities, production and economy, social culture and historical changes; (2) analyze the vegetation patterns, the interactions between vegetation and environmental factors (natural, social, economic, etc.) and the contributions of vegetation to the area, including the synthesis of the existing researches; and (3) provide the spatial arrangements of ecosystems and planning of each area, raise a comprehensive indicators of evaluation, evaluate the feasibility and soundness, and determine the optimum eco-productive paradigms for policy-makers which were land-use patterns within the threshold of ecological conservation. Three primitive paradigms of Maowusu (Mu Us) Ssandy Land, Loess Plateau and Huailai Basin in the farming-pastoral zone of northern China were proposed according to this paradigm system.展开更多
[Objective] A kind of biogas engineering geographic information system was designed and realized.[Method] Based on the data of the investigation of the large and medium-sized biogas projects in Beijing,the system user...[Objective] A kind of biogas engineering geographic information system was designed and realized.[Method] Based on the data of the investigation of the large and medium-sized biogas projects in Beijing,the system user's need and function demand were studied.Sub-system function was divided.By using SuperMap IS.NET,C# and SQL Server 2005 as the database and WebGIS frame,the system spatial and attribute database were designed so as to realize the WebGIS software of biogas project in Beijing.[Result] The system provided application platform for the distribution of biogas project information.User can realize the submission and inquiry the feedback of biogas project information based on system application right etc,so as to visually,fully and precisely inquiry project data.Based on the comprehensive analysis of data,the current state of biogas project and change trend were studied and decided.[Conclusion] The system provided convenience and services to relevant departments' planning and management of biogas project.展开更多
A physical isolation system based on PCI (peripheral component interconnect),embedded with intelligence card technology, strong identity authentication technology and securityaudit, etc., is introduced. The system can...A physical isolation system based on PCI (peripheral component interconnect),embedded with intelligence card technology, strong identity authentication technology and securityaudit, etc., is introduced. The system can physically isolate the internaland external networks. Thehardware of the system, including PCI interface control circuits, network interface circuits andlogic control circuits, is designed to automatically adapt its operation speed and mode to thenetwork and securely isolate the internal and external networks; the software of the system,including the security strategy management module, the security audit module, the database recordexchanging module, the file exchanging module and the mail exchanging module, is designed toefficiently exchange and manage the data transference between the internal and external networks.Also the driver of the system is implemented with Windows driver development kits (DDK) based onNetwork Driver Interface Specification (NDIS). The prototype ofthe system developed has beenemployed in the Police Fire Protection Bureau of Hubei Province, which performs consistently andefficiently. The technological cruxes discussed have practical values for related subjects.展开更多
The processing of measuri ng data plays an important role in reverse engineering. Based on grey system the ory, we first propose some methods to the processing of measuring data in revers e engineering. The measured d...The processing of measuri ng data plays an important role in reverse engineering. Based on grey system the ory, we first propose some methods to the processing of measuring data in revers e engineering. The measured data usually have some abnormalities. When the abnor mal data are eliminated by filtering, blanks are created. The grey generation an d GM(1,1) are used to create new data for these blanks. For the uneven data sequ en ce created by measuring error, the mean generation is used to smooth it and then the stepwise and smooth generations are used to improve the data sequence.展开更多
[Objective] The aim was to analyze effect of climate change on occurrence degree of cotton Lugus lucorum in coastal areas of Jiangsu Province, in order to provide authentic references for better prevention. [Method] S...[Objective] The aim was to analyze effect of climate change on occurrence degree of cotton Lugus lucorum in coastal areas of Jiangsu Province, in order to provide authentic references for better prevention. [Method] Statistical analysis was conducted on Information about occurrence degree of cotton Lugus lucorum in Binhai County in Jiangsu Province from 1985 to 2007 under guidance of Integral regression method. [Result] Because of climate change, cotton Lugus lucorum occurrence de- grees differed in different generations and growth stages in Binhai County. Tempera- ture and humidity constituted the main climate factors. In general, climate change hindered occurrence degree from increasing. We could make use of the period when occurrence degree of cotton Lugus lucorum is prone to significant increase and choose some periods, such as early April, late June and middle August, to improve prevention effect. In addition, attention should be paid to comprehensive measures, such as adjustment of industrial structure, which will reduce pesticide and minimize cotton Lugus lucorum damage and adverse impact from prevention measures. [Conclusion] The results provided authentic references for cotton Lugus lucorum preven- tion in Jiangsu coastal areas.展开更多
In order to reduce the enormous pressure to environmental monitoring work brought by the false sewage monitoring data, Grubbs method, box plot, t test and other methods are used to make depth analysis to the data, pro...In order to reduce the enormous pressure to environmental monitoring work brought by the false sewage monitoring data, Grubbs method, box plot, t test and other methods are used to make depth analysis to the data, providing a set of technological process to identify the sewage monitoring data, which is convenient and simple.展开更多
In this paper, based on the invariant subspace theory and adjoint operator concept of linear operator, a new matrix representation method is proposed to calculate the normal forms of n order general nonlinear dyna...In this paper, based on the invariant subspace theory and adjoint operator concept of linear operator, a new matrix representation method is proposed to calculate the normal forms of n order general nonlinear dynamic systems. In the method, there is no need to determine the structure of the class of normal forms in advance. Because the subspace is not related to the dimensions of the system and the order of the normal forms directly, it is determined only by a given vector field. So the normal forms with high orders and dimensions can be calculated by the method without difficulties. In this paper, is used the method for selecting the minimal subspace and solving homological equations in the subspace, the examples show that the method is very effective.展开更多
B2B E Commerce is one of the most potential electronic commerce forms at present. But since traditional B2 B E Commerce system lacks an unified standard and solution of basic architectur e a nd interface, it has m...B2B E Commerce is one of the most potential electronic commerce forms at present. But since traditional B2 B E Commerce system lacks an unified standard and solution of basic architectur e a nd interface, it has many shortcomings such as poor reusability and poor extensi bility. In order to solve the problem, combined with Web Service technology, a B 2B E Commerce system model based on Web Service is proposed and analyzed. The m odel can combine relatively independent Web Service on Intranet and Internet by constructing core application program. As a part of supply chain, it can also pr ovide a standard interface for other applications such as ERP/CRM/SCM, etc. Th er efore, B2B E Commerce system with this form is easy for development, integratio n and maintenance. Finally, a solution of B2B E Commerce system based on Web Se rvice is propounded by introducing an instance.展开更多
In the Engine CAD application system engineering database management system (ECAD-EDBMS) is the kernel. ECAD-EDBMS can manage and process the multimedia such as graphics, data, text, sound, image and video. It provide...In the Engine CAD application system engineering database management system (ECAD-EDBMS) is the kernel. ECAD-EDBMS can manage and process the multimedia such as graphics, data, text, sound, image and video. It provides the integrated environment and more functions for many subsystems of ECAD and engine designers. So it improves the design efficiency.展开更多
A differential equation for calculating squeeze-film air damping in slotted plates is developed by modifying the Reynolds equation. A term is added to account for the effect of airflow through the slots on the air dam...A differential equation for calculating squeeze-film air damping in slotted plates is developed by modifying the Reynolds equation. A term is added to account for the effect of airflow through the slots on the air damping of the plate. The end effect of the airflow in the slots is also treated by substituting an effective channel length for the geometric channel length (i. e. the thickness of the plate)..The damping pressure distribution, damping force, and damping force coefficient of the slotted plates can be found by solving the equation under appropriate boundary conditions. With restrictions on the thickness and the lateral dimensions of the slotted plate removed,the equation provides a useful tool for analysing the squeeze-film air damping effect of slotted plates with finite thickness and finite lateral dimensions. For a typical slotted plate structure, the damping force coefficient obtained by this equation agrees well with that generated by ANSYS.展开更多
A rational equation of state of the perturbation type with a repulsion and attraction term has been applied to reproduce critical curves of six different binary systems up to high temperatures and pressures. A square ...A rational equation of state of the perturbation type with a repulsion and attraction term has been applied to reproduce critical curves of six different binary systems up to high temperatures and pressures. A square well potential for intermolecular interaction is used. With pairwise combination rules for these potentials three adjustable parameters are needed. The experimental critical point and phase equilibrium data are compared with the values predicted using the equation of state. Good agreement is obtained for the analysis of the critical pressure composition data and molar volumes.展开更多
基金Supported by the Joint Funds of National Natural Science Foundation of China(61039001)~~
文摘In order to grasp the evolution of flight conflict amount accurately and to forecast the amount, chaos in flight conflicts is studied. Firstly, a fault tree of flight conflicts is established based on the man-machine-environ- ment system engineering theory. The chaotic characteristics of flight conflict are analyzed from the qualitative point of view. Secondly, an improved chaotic algorithm for the largest Lyapunov exponent is proposed based on the small-data method and the wavelet de-noising theory. Chaos in flight conflict time series is identified by the improved chaotic algorithm from the quantitative point of view. Finally, a case study by the chaos forecasting al- gorithm is performed and the results are evaluated by the gray error checking : Correlative value of posterior error is 0. 220 9〈0. 35, and micro-error probability is 0. 985 3〉0.95. Such results show the chaos forecasting algo- rithm is effective, thus it is feasible to analyze and forecast flight conflict by chaotic theory.
文摘The farming-pastoral zone of northern China plays a dual role in ecological conditions and production and occupies an important position in the national economy. In this paper, the methodology of system engineering is introduced to construct and optimize an eco-productive paradigm system for the typical areas of the farming-pastoral zone. The system was constructed in the following steps: (1) design the framework of the paradigm system based on the data of physical site characteristics, biocommunities, production and economy, social culture and historical changes; (2) analyze the vegetation patterns, the interactions between vegetation and environmental factors (natural, social, economic, etc.) and the contributions of vegetation to the area, including the synthesis of the existing researches; and (3) provide the spatial arrangements of ecosystems and planning of each area, raise a comprehensive indicators of evaluation, evaluate the feasibility and soundness, and determine the optimum eco-productive paradigms for policy-makers which were land-use patterns within the threshold of ecological conservation. Three primitive paradigms of Maowusu (Mu Us) Ssandy Land, Loess Plateau and Huailai Basin in the farming-pastoral zone of northern China were proposed according to this paradigm system.
基金Supported by Countryside Energy Comprehensive Construction Pro-ject of Science,Technology and Education Branch of AgriculturalDepartment [AFD2009J54]~~
文摘[Objective] A kind of biogas engineering geographic information system was designed and realized.[Method] Based on the data of the investigation of the large and medium-sized biogas projects in Beijing,the system user's need and function demand were studied.Sub-system function was divided.By using SuperMap IS.NET,C# and SQL Server 2005 as the database and WebGIS frame,the system spatial and attribute database were designed so as to realize the WebGIS software of biogas project in Beijing.[Result] The system provided application platform for the distribution of biogas project information.User can realize the submission and inquiry the feedback of biogas project information based on system application right etc,so as to visually,fully and precisely inquiry project data.Based on the comprehensive analysis of data,the current state of biogas project and change trend were studied and decided.[Conclusion] The system provided convenience and services to relevant departments' planning and management of biogas project.
文摘A physical isolation system based on PCI (peripheral component interconnect),embedded with intelligence card technology, strong identity authentication technology and securityaudit, etc., is introduced. The system can physically isolate the internaland external networks. Thehardware of the system, including PCI interface control circuits, network interface circuits andlogic control circuits, is designed to automatically adapt its operation speed and mode to thenetwork and securely isolate the internal and external networks; the software of the system,including the security strategy management module, the security audit module, the database recordexchanging module, the file exchanging module and the mail exchanging module, is designed toefficiently exchange and manage the data transference between the internal and external networks.Also the driver of the system is implemented with Windows driver development kits (DDK) based onNetwork Driver Interface Specification (NDIS). The prototype ofthe system developed has beenemployed in the Police Fire Protection Bureau of Hubei Province, which performs consistently andefficiently. The technological cruxes discussed have practical values for related subjects.
文摘The processing of measuri ng data plays an important role in reverse engineering. Based on grey system the ory, we first propose some methods to the processing of measuring data in revers e engineering. The measured data usually have some abnormalities. When the abnor mal data are eliminated by filtering, blanks are created. The grey generation an d GM(1,1) are used to create new data for these blanks. For the uneven data sequ en ce created by measuring error, the mean generation is used to smooth it and then the stepwise and smooth generations are used to improve the data sequence.
文摘[Objective] The aim was to analyze effect of climate change on occurrence degree of cotton Lugus lucorum in coastal areas of Jiangsu Province, in order to provide authentic references for better prevention. [Method] Statistical analysis was conducted on Information about occurrence degree of cotton Lugus lucorum in Binhai County in Jiangsu Province from 1985 to 2007 under guidance of Integral regression method. [Result] Because of climate change, cotton Lugus lucorum occurrence de- grees differed in different generations and growth stages in Binhai County. Tempera- ture and humidity constituted the main climate factors. In general, climate change hindered occurrence degree from increasing. We could make use of the period when occurrence degree of cotton Lugus lucorum is prone to significant increase and choose some periods, such as early April, late June and middle August, to improve prevention effect. In addition, attention should be paid to comprehensive measures, such as adjustment of industrial structure, which will reduce pesticide and minimize cotton Lugus lucorum damage and adverse impact from prevention measures. [Conclusion] The results provided authentic references for cotton Lugus lucorum preven- tion in Jiangsu coastal areas.
文摘In order to reduce the enormous pressure to environmental monitoring work brought by the false sewage monitoring data, Grubbs method, box plot, t test and other methods are used to make depth analysis to the data, providing a set of technological process to identify the sewage monitoring data, which is convenient and simple.
文摘In this paper, based on the invariant subspace theory and adjoint operator concept of linear operator, a new matrix representation method is proposed to calculate the normal forms of n order general nonlinear dynamic systems. In the method, there is no need to determine the structure of the class of normal forms in advance. Because the subspace is not related to the dimensions of the system and the order of the normal forms directly, it is determined only by a given vector field. So the normal forms with high orders and dimensions can be calculated by the method without difficulties. In this paper, is used the method for selecting the minimal subspace and solving homological equations in the subspace, the examples show that the method is very effective.
文摘B2B E Commerce is one of the most potential electronic commerce forms at present. But since traditional B2 B E Commerce system lacks an unified standard and solution of basic architectur e a nd interface, it has many shortcomings such as poor reusability and poor extensi bility. In order to solve the problem, combined with Web Service technology, a B 2B E Commerce system model based on Web Service is proposed and analyzed. The m odel can combine relatively independent Web Service on Intranet and Internet by constructing core application program. As a part of supply chain, it can also pr ovide a standard interface for other applications such as ERP/CRM/SCM, etc. Th er efore, B2B E Commerce system with this form is easy for development, integratio n and maintenance. Finally, a solution of B2B E Commerce system based on Web Se rvice is propounded by introducing an instance.
文摘In the Engine CAD application system engineering database management system (ECAD-EDBMS) is the kernel. ECAD-EDBMS can manage and process the multimedia such as graphics, data, text, sound, image and video. It provides the integrated environment and more functions for many subsystems of ECAD and engine designers. So it improves the design efficiency.
文摘A differential equation for calculating squeeze-film air damping in slotted plates is developed by modifying the Reynolds equation. A term is added to account for the effect of airflow through the slots on the air damping of the plate. The end effect of the airflow in the slots is also treated by substituting an effective channel length for the geometric channel length (i. e. the thickness of the plate)..The damping pressure distribution, damping force, and damping force coefficient of the slotted plates can be found by solving the equation under appropriate boundary conditions. With restrictions on the thickness and the lateral dimensions of the slotted plate removed,the equation provides a useful tool for analysing the squeeze-film air damping effect of slotted plates with finite thickness and finite lateral dimensions. For a typical slotted plate structure, the damping force coefficient obtained by this equation agrees well with that generated by ANSYS.
文摘A rational equation of state of the perturbation type with a repulsion and attraction term has been applied to reproduce critical curves of six different binary systems up to high temperatures and pressures. A square well potential for intermolecular interaction is used. With pairwise combination rules for these potentials three adjustable parameters are needed. The experimental critical point and phase equilibrium data are compared with the values predicted using the equation of state. Good agreement is obtained for the analysis of the critical pressure composition data and molar volumes.