In order to improve the detection accuracy of Doppler asymmetric spatial heterodyne(DASH)interferometer in harsh temperatures,an opto-mechanical-thermal integration analysis is carried out.Firstly,the correlation betw...In order to improve the detection accuracy of Doppler asymmetric spatial heterodyne(DASH)interferometer in harsh temperatures,an opto-mechanical-thermal integration analysis is carried out.Firstly,the correlation between the interference phase and temperature is established according to the working principle and the phase algorithm of the interferometer.Secondly,the optical mechanical thermal analysis model and thermal deformation data acquisition model are designed.The deformation data of the interference module and the imaging optical system at different temperatures are given by temperature load simulation analysis,and the phase error caused by thermal deformation is obtained by fitting.Finally,based on the wind speed error caused by thermal deformation of each component,a reasonable temperature control scheme is proposed.The results show that the interference module occupies the main cause,the temperature must be controlled within(20±0.05)℃,and the temperature control should be carried out for the temperature sensitive parts,and the wind speed error caused by the part is 3.8 m/s.The thermal drift between the magnification of the imaging optical system and the thermal drift of the relative position between the imaging optical system and the detector should occupy the secondary cause,which should be controlled within(20±2)℃,and the wind speed error caused by the part is 3.05 m/s.In summary,the wind measurement error caused by interference module,imaging optical system,and the relative position between the imaging optical system and the detector can be controlled within 6.85 m/s.The analysis and temperature control schemes presented in this paper can provide theoretical basis for DASH interferometer engineering applications.展开更多
A hierarchical structural decomposition analysis(SDA) model has been developed based on process-level input-output(I-O) tables to analyze the drivers of energy consumption changes in an integrated steel plant during 2...A hierarchical structural decomposition analysis(SDA) model has been developed based on process-level input-output(I-O) tables to analyze the drivers of energy consumption changes in an integrated steel plant during 2011-2013. By combining the principle of hierarchical decomposition into D&L method, a hierarchical decomposition model for multilevel SDA is obtained. The developed hierarchical IO-SDA model would provide consistent results and need less computation effort compared with the traditional SDA model. The decomposition results of the steel plant suggest that the technology improvement and reduced steel final demand are two major reasons for declined total energy consumption. The technical improvements of blast furnaces, basic oxygen furnaces, the power plant and the by-products utilization level have contributed mostly in reducing energy consumption. A major retrofit of ancillary process units and solving fuel substitution problem in the sinter plant and blast furnace are important for further energy saving. Besides the empirical results, this work also discussed that why and how hierarchical SDA can be applied in a process-level decomposition analysis of aggregated indicators.展开更多
This paper creates 3D solid model and assembly of U RJ 92-6 oil tank and analyses its strength by integrated CAD/CAE/CAM software I-D EAS. Through integrated simulation in computer, design efficiency and quality of oi...This paper creates 3D solid model and assembly of U RJ 92-6 oil tank and analyses its strength by integrated CAD/CAE/CAM software I-D EAS. Through integrated simulation in computer, design efficiency and quality of oil tank is greatly improved. Adopting integrated CAD/CAE/CAM software to carry out integrated research to equ ipment and products, we will be able to take overall analysis in aspects of 3-D solid modeling, pre-assembly and strength, etc., to realize non-paper designi ng and parallel designing. Problems can be found and settled during designing, w hich will increase designing efficiency and one-time success rate and realize o ptimum designing for products.展开更多
As the increase of the complexity of the information warfare,its intervention strategy needs to be designed in an integrated environment.However,the current research always breaks the internal relation between equipme...As the increase of the complexity of the information warfare,its intervention strategy needs to be designed in an integrated environment.However,the current research always breaks the internal relation between equipment and tactics,and it is difficult to meet the requirements of their integrated analysis.In this paper,the research status quo of the integrated analysis about equipment and tactics is discussed first,some shortages of the current methods are summarized then,and an evolvement mechanism of the integrated analysis for equipment and tactics is given finally.Based on these,a framework of integrated analysis is proposed.This method's effectiveness is validated by an example.展开更多
Process Capability Analysis (PCA) is a powerful too l to assess the ability of a process for manufacturing product that meets specific ations. The larger process capability index implies the higher process yield, a nd...Process Capability Analysis (PCA) is a powerful too l to assess the ability of a process for manufacturing product that meets specific ations. The larger process capability index implies the higher process yield, a nd the larger process capability index also indicates the lower process expected loss. Chen et al. (2001) has applied indices C pu, C pl, and C pk for evaluating the process capability for a multi-process product wi th smaller-the-better, larger-the-better, and nominal-the-best specificati ons respectively. However, C pk cannot reasonably reflect the process expected loss. In this paper, index C pn is selected to replace C pk. Indices C pu, C pl, and C pn are used to evalu ate the entire process capability for a multi-process product with smaller-the -better, larger-the-better, and nominal-the-best specifications respectivel y. An integrated process capability index for a multi-process product is propo sed. The relationship between process capability index and the process yield is introduced. A multi-process capability analysis chart (MPCAC), reasonably rev ealing the status of process capability for the entire product, is constructed f or practical application. An evaluating procedure of the process capability for the entire product is also provided.展开更多
With the dramatic development of renewable energy all over the world,and for purpose of adjusting energy structure,the Ministry of Construction of China plans to promote the large scale application of renewable energy...With the dramatic development of renewable energy all over the world,and for purpose of adjusting energy structure,the Ministry of Construction of China plans to promote the large scale application of renewable energy in buildings. In order to ensure the validity of policy-making,this work firstly exerts a method to do cost-benefit analysis for three kinds of technologies such as building-integrated solar hot water (BISHW) system,building-integrated photovoltaic (BIPV) technology and ground water heat pump (GWHP). Through selecting a representative city of every climate region,the analysis comes into different results for different climate regions in China and respectively different suggestion for policy-making. On the analysis basis,the Ministry of Construction (MOC) and the Ministry of Finance of China (MOF) united to start-up Building-integrated Renewable Energy Demonstration Projects (BIREDP) in 2006. In the demonstration projects,renewable energy takes place of traditional energy to supply the domestic hot water,electricity,air-conditioning and heating. Through carrying out the demonstration projects,renewable energy related market has been expanded. More and more relative companies and local governments take the opportunity to promote the large scale application of renewable energy in buildings.展开更多
Several new MEMS Inertial Measurement Unit(IMU) sensor products have been released recently with improved performance,which have the potential to support much higher precision applications.New MEMS IMUs include the Na...Several new MEMS Inertial Measurement Unit(IMU) sensor products have been released recently with improved performance,which have the potential to support much higher precision applications.New MEMS IMUs include the NavChip from InterSense,the Nav440 from Crossbow,the Landmark30/40 from GTI,the SDI500 from Systron Donner.Since they are new in the market,currently there is limited information about their error characterization which however is important for the construction of proper error models for their integration with other sensors such as GPS.This paper will investigate the error characterization of two new MEMS IMU sensors,namely the NavChip and Nav440,using Allan variance technique.In addition to identifying different error terms,different stochastic error modeling methods,such as Gauss-Markov(GM) and Autoregressive(AR) processes,will also be investigated to assess the MEMS IMU sensor biases.Investigation to integrate new MEMS IMU sensors with Precise Point Positioning(PPP) will also be conducted to address the re-convergence issues.展开更多
In e-commerce the multidimensional data analysis based on the Web data needs integrating various data sources such as XML data and relational data on the conceptual level. A conceptual data description approach to mul...In e-commerce the multidimensional data analysis based on the Web data needs integrating various data sources such as XML data and relational data on the conceptual level. A conceptual data description approach to multidimensional data model the UML galaxy diagram is presented in order to conduct multidimensional data analysis for multiple subjects. The approach is illuminated using a case of 2_roots UML galaxy diagram that takes marketing analysis of TV products involved one retailer and several suppliers into consideration.展开更多
It is necessary to use the integrated stainless steel pipe having two fitting bodies without welds while train travelling at high speed. In order to form this type of integrated stainless steel pipe, the method of pre...It is necessary to use the integrated stainless steel pipe having two fitting bodies without welds while train travelling at high speed. In order to form this type of integrated stainless steel pipe, the method of preforming combined finish forming process is developed. The preforming process is characterized by flaring combined upsetting for left fitting body which is like a flange, and is characterized by tube axial compressive process under die constraint for right fitting body which is like a double-wall pipe. The finite element simulations of the processes are carried out by software package DEFORM, and the results indicate that: 1) left or right fitting body can be formed by a two-step forming process without folding and under-filling defects; 2) by using two-step forming, strain and stress in left fitting body are larger than those in right fitting body, and deformation in right fitting body is more homogenous than the deformation in left fitting body; 3) two or more preforming steps may be needed for left fitting body considering the distributions of strain and stress.展开更多
Numerous innovative heat recovery-to-power technologies have been resourcefully and technologically exploited to bridge the growing gap between energy needs and its sustainable and affordable supply.Among them,the pro...Numerous innovative heat recovery-to-power technologies have been resourcefully and technologically exploited to bridge the growing gap between energy needs and its sustainable and affordable supply.Among them,the proposed trilateral-cycle(TLC) power system exhibits high thermodynamic efficiency during heat recovery-to-power from low-to-medium temperature heat sources.The TLCs are proposed and analysed using n-pentane as working fluid for waste heat recovery-to-power generation from low-grade heat source to evaluate the thermodynamic efficiency of the cycles.Four different single stage TLC configurations with distinct working principles are modelled thermodynamically using engineering equation solver.Based on the thermodynamic framework,thermodynamic performance simulation and efficiency analysis of the cycles as well as the exergy efficiencies of the heating and condensing processes are carried out and compared in their efficiency.The results show that the simple TLC,recuperated TLC,reheat TLC and regenerative TLC operating at subcritical conditions with cycle high temperature of 473 K can attain thermal efficiencies of 21.97%,23.91%,22.07% and 22.9%,respectively.The recuperated TLC attains the highest thermodynamic efficiency at the cycle high temperature because of its lowest exergy destruction rates in the heat exchanger and condenser.The efficiency analysis carried out would assist in guiding thermodynamic process development and thermal integration of the proposed cycles.展开更多
Focusing on electronic products,this paper establishes a finite element model for printed circuit board(PCB)assembling with enhanced ball grid array(EBGA)component under vibration environment.Based on this model,it st...Focusing on electronic products,this paper establishes a finite element model for printed circuit board(PCB)assembling with enhanced ball grid array(EBGA)component under vibration environment.Based on this model,it studies relations between fatigue rate of solder joint and temperature,vibration frequency.Moreover,it analyzes propagation of micro-crack produced by thermal cycle under vibration stress.The results offer a method to optimize the thermal cycle and vibration integrated profile and to combine vibration test and thermal cycling for highly accelerated life test(HALT).展开更多
It is important but difficult to analyze the electromagnetic environment effect(E3) in the designing of modern airborne,sea,space,and ground systems.Thus a hybrid algorithm of time domain integral equation,finite diff...It is important but difficult to analyze the electromagnetic environment effect(E3) in the designing of modern airborne,sea,space,and ground systems.Thus a hybrid algorithm of time domain integral equation,finite difference time domain and modified nodal analysis(TDIE-FDTD-MNA) is developed to analyze the E3 of complex systems with cables and nonlinear circuit structures.The plane wave time domain(PWTD) enhanced TDIE method is adopted to solve field problems.The higher order FDTD(2,4) is adopted to solve cable problems.The MNA is adopted to obtain the response of complex circuits(with nonlinear structures).Numerical examples demonstrate the effectiveness of the proposed algorithm.展开更多
文摘In order to improve the detection accuracy of Doppler asymmetric spatial heterodyne(DASH)interferometer in harsh temperatures,an opto-mechanical-thermal integration analysis is carried out.Firstly,the correlation between the interference phase and temperature is established according to the working principle and the phase algorithm of the interferometer.Secondly,the optical mechanical thermal analysis model and thermal deformation data acquisition model are designed.The deformation data of the interference module and the imaging optical system at different temperatures are given by temperature load simulation analysis,and the phase error caused by thermal deformation is obtained by fitting.Finally,based on the wind speed error caused by thermal deformation of each component,a reasonable temperature control scheme is proposed.The results show that the interference module occupies the main cause,the temperature must be controlled within(20±0.05)℃,and the temperature control should be carried out for the temperature sensitive parts,and the wind speed error caused by the part is 3.8 m/s.The thermal drift between the magnification of the imaging optical system and the thermal drift of the relative position between the imaging optical system and the detector should occupy the secondary cause,which should be controlled within(20±2)℃,and the wind speed error caused by the part is 3.05 m/s.In summary,the wind measurement error caused by interference module,imaging optical system,and the relative position between the imaging optical system and the detector can be controlled within 6.85 m/s.The analysis and temperature control schemes presented in this paper can provide theoretical basis for DASH interferometer engineering applications.
基金Project(2012GK2025)supported by Science-Technology Plan Foundation of Hunan Province,ChinaProject(2013zzts039)supported by the Fundamental Research Funds for Central South University,China
文摘A hierarchical structural decomposition analysis(SDA) model has been developed based on process-level input-output(I-O) tables to analyze the drivers of energy consumption changes in an integrated steel plant during 2011-2013. By combining the principle of hierarchical decomposition into D&L method, a hierarchical decomposition model for multilevel SDA is obtained. The developed hierarchical IO-SDA model would provide consistent results and need less computation effort compared with the traditional SDA model. The decomposition results of the steel plant suggest that the technology improvement and reduced steel final demand are two major reasons for declined total energy consumption. The technical improvements of blast furnaces, basic oxygen furnaces, the power plant and the by-products utilization level have contributed mostly in reducing energy consumption. A major retrofit of ancillary process units and solving fuel substitution problem in the sinter plant and blast furnace are important for further energy saving. Besides the empirical results, this work also discussed that why and how hierarchical SDA can be applied in a process-level decomposition analysis of aggregated indicators.
文摘This paper creates 3D solid model and assembly of U RJ 92-6 oil tank and analyses its strength by integrated CAD/CAE/CAM software I-D EAS. Through integrated simulation in computer, design efficiency and quality of oil tank is greatly improved. Adopting integrated CAD/CAE/CAM software to carry out integrated research to equ ipment and products, we will be able to take overall analysis in aspects of 3-D solid modeling, pre-assembly and strength, etc., to realize non-paper designi ng and parallel designing. Problems can be found and settled during designing, w hich will increase designing efficiency and one-time success rate and realize o ptimum designing for products.
基金Sponsored by the National Natural Science Foundation(71101149,71071160,91024006)Natural Science Foundation of Hunan Province(11JJ4065)Ph.D.Programs Foundation of Ministry of Education of China(20104307120020)
文摘As the increase of the complexity of the information warfare,its intervention strategy needs to be designed in an integrated environment.However,the current research always breaks the internal relation between equipment and tactics,and it is difficult to meet the requirements of their integrated analysis.In this paper,the research status quo of the integrated analysis about equipment and tactics is discussed first,some shortages of the current methods are summarized then,and an evolvement mechanism of the integrated analysis for equipment and tactics is given finally.Based on these,a framework of integrated analysis is proposed.This method's effectiveness is validated by an example.
文摘Process Capability Analysis (PCA) is a powerful too l to assess the ability of a process for manufacturing product that meets specific ations. The larger process capability index implies the higher process yield, a nd the larger process capability index also indicates the lower process expected loss. Chen et al. (2001) has applied indices C pu, C pl, and C pk for evaluating the process capability for a multi-process product wi th smaller-the-better, larger-the-better, and nominal-the-best specificati ons respectively. However, C pk cannot reasonably reflect the process expected loss. In this paper, index C pn is selected to replace C pk. Indices C pu, C pl, and C pn are used to evalu ate the entire process capability for a multi-process product with smaller-the -better, larger-the-better, and nominal-the-best specifications respectivel y. An integrated process capability index for a multi-process product is propo sed. The relationship between process capability index and the process yield is introduced. A multi-process capability analysis chart (MPCAC), reasonably rev ealing the status of process capability for the entire product, is constructed f or practical application. An evaluating procedure of the process capability for the entire product is also provided.
文摘With the dramatic development of renewable energy all over the world,and for purpose of adjusting energy structure,the Ministry of Construction of China plans to promote the large scale application of renewable energy in buildings. In order to ensure the validity of policy-making,this work firstly exerts a method to do cost-benefit analysis for three kinds of technologies such as building-integrated solar hot water (BISHW) system,building-integrated photovoltaic (BIPV) technology and ground water heat pump (GWHP). Through selecting a representative city of every climate region,the analysis comes into different results for different climate regions in China and respectively different suggestion for policy-making. On the analysis basis,the Ministry of Construction (MOC) and the Ministry of Finance of China (MOF) united to start-up Building-integrated Renewable Energy Demonstration Projects (BIREDP) in 2006. In the demonstration projects,renewable energy takes place of traditional energy to supply the domestic hot water,electricity,air-conditioning and heating. Through carrying out the demonstration projects,renewable energy related market has been expanded. More and more relative companies and local governments take the opportunity to promote the large scale application of renewable energy in buildings.
基金Excellent talents Program of Liaoning Province(LR2011007)supported by the Natural Sciences and Engineering Research Council(NSERC)of Canada and Tecterra as well as Program for Liaoning Excellent Talents in University,China~~
文摘Several new MEMS Inertial Measurement Unit(IMU) sensor products have been released recently with improved performance,which have the potential to support much higher precision applications.New MEMS IMUs include the NavChip from InterSense,the Nav440 from Crossbow,the Landmark30/40 from GTI,the SDI500 from Systron Donner.Since they are new in the market,currently there is limited information about their error characterization which however is important for the construction of proper error models for their integration with other sensors such as GPS.This paper will investigate the error characterization of two new MEMS IMU sensors,namely the NavChip and Nav440,using Allan variance technique.In addition to identifying different error terms,different stochastic error modeling methods,such as Gauss-Markov(GM) and Autoregressive(AR) processes,will also be investigated to assess the MEMS IMU sensor biases.Investigation to integrate new MEMS IMU sensors with Precise Point Positioning(PPP) will also be conducted to address the re-convergence issues.
基金This project was supported by China Postdoctoral Science Foundation (2005037506) and the National Natural ScienceFoundation of China (70472029)
文摘In e-commerce the multidimensional data analysis based on the Web data needs integrating various data sources such as XML data and relational data on the conceptual level. A conceptual data description approach to multidimensional data model the UML galaxy diagram is presented in order to conduct multidimensional data analysis for multiple subjects. The approach is illuminated using a case of 2_roots UML galaxy diagram that takes marketing analysis of TV products involved one retailer and several suppliers into consideration.
基金Project(51305334)supported by the National Natural Science Foundation of ChinaProject(51335009)supported by the National Natural Science Foundation of China for Key Program+1 种基金Project(CXY1442(4))supported by the Science and Technology Planning Project of Xi’an,ChinaProject supported by Shaanxi Province Postdoctoral Science Research Program of China
文摘It is necessary to use the integrated stainless steel pipe having two fitting bodies without welds while train travelling at high speed. In order to form this type of integrated stainless steel pipe, the method of preforming combined finish forming process is developed. The preforming process is characterized by flaring combined upsetting for left fitting body which is like a flange, and is characterized by tube axial compressive process under die constraint for right fitting body which is like a double-wall pipe. The finite element simulations of the processes are carried out by software package DEFORM, and the results indicate that: 1) left or right fitting body can be formed by a two-step forming process without folding and under-filling defects; 2) by using two-step forming, strain and stress in left fitting body are larger than those in right fitting body, and deformation in right fitting body is more homogenous than the deformation in left fitting body; 3) two or more preforming steps may be needed for left fitting body considering the distributions of strain and stress.
基金The University of Ilorin,Nigeria financially supported this research through scholarship grant from Tertiary Education Trust Fund
文摘Numerous innovative heat recovery-to-power technologies have been resourcefully and technologically exploited to bridge the growing gap between energy needs and its sustainable and affordable supply.Among them,the proposed trilateral-cycle(TLC) power system exhibits high thermodynamic efficiency during heat recovery-to-power from low-to-medium temperature heat sources.The TLCs are proposed and analysed using n-pentane as working fluid for waste heat recovery-to-power generation from low-grade heat source to evaluate the thermodynamic efficiency of the cycles.Four different single stage TLC configurations with distinct working principles are modelled thermodynamically using engineering equation solver.Based on the thermodynamic framework,thermodynamic performance simulation and efficiency analysis of the cycles as well as the exergy efficiencies of the heating and condensing processes are carried out and compared in their efficiency.The results show that the simple TLC,recuperated TLC,reheat TLC and regenerative TLC operating at subcritical conditions with cycle high temperature of 473 K can attain thermal efficiencies of 21.97%,23.91%,22.07% and 22.9%,respectively.The recuperated TLC attains the highest thermodynamic efficiency at the cycle high temperature because of its lowest exergy destruction rates in the heat exchanger and condenser.The efficiency analysis carried out would assist in guiding thermodynamic process development and thermal integration of the proposed cycles.
基金Sponsored by the National Advanced Research Project of China(41319030101)
文摘Focusing on electronic products,this paper establishes a finite element model for printed circuit board(PCB)assembling with enhanced ball grid array(EBGA)component under vibration environment.Based on this model,it studies relations between fatigue rate of solder joint and temperature,vibration frequency.Moreover,it analyzes propagation of micro-crack produced by thermal cycle under vibration stress.The results offer a method to optimize the thermal cycle and vibration integrated profile and to combine vibration test and thermal cycling for highly accelerated life test(HALT).
基金supported by National Basic Research Program of China(973 Program)
文摘It is important but difficult to analyze the electromagnetic environment effect(E3) in the designing of modern airborne,sea,space,and ground systems.Thus a hybrid algorithm of time domain integral equation,finite difference time domain and modified nodal analysis(TDIE-FDTD-MNA) is developed to analyze the E3 of complex systems with cables and nonlinear circuit structures.The plane wave time domain(PWTD) enhanced TDIE method is adopted to solve field problems.The higher order FDTD(2,4) is adopted to solve cable problems.The MNA is adopted to obtain the response of complex circuits(with nonlinear structures).Numerical examples demonstrate the effectiveness of the proposed algorithm.
