In this paper, novel mathematical expressions are derived for the Global Positioning System (GPS) receiver interference tolerance in the presence of different types of interference signals such as: continuous wave int...In this paper, novel mathematical expressions are derived for the Global Positioning System (GPS) receiver interference tolerance in the presence of different types of interference signals such as: continuous wave interference, narrowband interference, partial band interference, broadband interference, match spectrum interference and pulse interference. Also, in this paper the mean time to loss lock is determined in order to analyse the mentioned interferences effect on the GPS receiver. These derived analytical expressions are validated with the aid of extensive simulation experiments.展开更多
With the actuality and characteristic and requirement of rural power enterprise distribution network management, this article introduced the function of geographic information system on the framework of distribution n...With the actuality and characteristic and requirement of rural power enterprise distribution network management, this article introduced the function of geographic information system on the framework of distribution network, in order to develop rural distribution network.展开更多
Analyses of the effects of some parameters were performed to determine the admittance functions in a common two-compartment building with background porosity by the imposed excitation method.Variations of the magnific...Analyses of the effects of some parameters were performed to determine the admittance functions in a common two-compartment building with background porosity by the imposed excitation method.Variations of the magnification factors of fluctuating internal pressures were analyzed using 96 model cases under random fluctuating external pressure,and then corresponding design equations were fitted.The results show that the Helmholtz resonance peaks of the admittance functions in both compartments increase with increasing the area of windward or partition wall opening.With increasing the volume of the compartment with an external opening,the resonance peak in this compartment at the higher Helmholtz frequency significantly decreases,at the same time,the resonance peak in the other compartment at the lower Helmholtz frequency also decreases.With increasing the volume of the compartment with background porosity,both resonance peaks in this compartment at the lower and higher Helmholtz frequencies decrease,meanwhile,the resonance peak at the lower Helmholtz frequency for the other compartment also decreases,whereas the resonance peak at the higher Helmholtz frequency increases.Both resonance peaks of the admittance functions in the two compartments decrease with increasing the amplitude of fluctuating external pressure coefficients or reference wind speed.展开更多
In this research,mechanical stress,static strain and deformation analyses of a cylindrical pressure vessel subjected to mechanical loads are presented.The kinematic relations are developed based on higherorder sinusoi...In this research,mechanical stress,static strain and deformation analyses of a cylindrical pressure vessel subjected to mechanical loads are presented.The kinematic relations are developed based on higherorder sinusoidal shear deformation theory.Thickness stretching formulation is accounted for more accurate analysis.The total transverse deflection is divided into bending,shear and thickness stretching parts in which the third term is responsible for change of deflection along the thickness direction.The axisymmetric formulations are derived through principle of virtual work.A parametric study is presented to investigate variation of stress and strain components along the thickness and longitudinal directions.To explore effect of thickness stretching model on the static results,a comparison between the present results with the available results of literature is presented.As an important output,effect of micro-scale parameter is studied on the static stress and strain distribution.展开更多
Studies on the cold-responsive genes and cold signaling of woody species drop far behind in comparison to herbaceous plants.Due to similar lignified structure,perennial characteristic,and enhanced tolerance,it seems m...Studies on the cold-responsive genes and cold signaling of woody species drop far behind in comparison to herbaceous plants.Due to similar lignified structure,perennial characteristic,and enhanced tolerance,it seems much easier to find strongly antifreeze genes and obtain effective results in transgenic woody plants.In this study,Ammopiptanthus mongolicus,an evergreen,broadleaf and cold-resist leguminous shrub growing in the desert of Inner Mongolia,was used as a material for low-temperature induced gene isolation.Through differential expression analysis induced by low-temperature,thirteen up-regulated cDNAs were identified.One of them,AmEBP1,(accession number:DQ519359)confers enhanced cold-tolerance to both transgenic E.coli and transgenic Arabidopsis.Results suggest that AmEBP1 can stimulate the synthesis of ribosome and the dephosphyration of the α-subunit of initiation factor 2(eIF2α),and subsequently promote the translation process.By which the transgenic plants obtained increased cold-resistant ability.展开更多
Geometry optimization of p-C_(6)H_(4)-connected cyclo[20]carbon(p-C_(6)H_(4)-C_(20))was carried out at M062X/6-311G(d,p)level,three kinds of bond orders(Mayer,Laplacian,and Wiberg),electron-hole distributions,localize...Geometry optimization of p-C_(6)H_(4)-connected cyclo[20]carbon(p-C_(6)H_(4)-C_(20))was carried out at M062X/6-311G(d,p)level,three kinds of bond orders(Mayer,Laplacian,and Wiberg),electron-hole distributions,localized orbital locators(LOL),and infrared(IR)spectrum were also performed at the same level.Based on TD-DFT M062X/6-311G(d,p)method,the first 20 excited states and ultraviolet(UV)spectra of p-C_(6)H_(4)-C_(20) were calculated.Calculation results of π-electron delocalization analyses prove thatπ-electron delocalization of p-C_(6)H_(4)-C_(20) is more likely to occur on shorter C-C bonds rather than longer C-C bonds,and inside/outside of the ring plane rather than above/below the ring plane.Two absorption peaks of p-C_(6)H_(4)-C_(20) locate at about 319 nm and 236 nm,respectively.展开更多
文摘In this paper, novel mathematical expressions are derived for the Global Positioning System (GPS) receiver interference tolerance in the presence of different types of interference signals such as: continuous wave interference, narrowband interference, partial band interference, broadband interference, match spectrum interference and pulse interference. Also, in this paper the mean time to loss lock is determined in order to analyse the mentioned interferences effect on the GPS receiver. These derived analytical expressions are validated with the aid of extensive simulation experiments.
基金Science and Technology Research Instruction Project of Heilongjiang Province Education Department (9553032)
文摘With the actuality and characteristic and requirement of rural power enterprise distribution network management, this article introduced the function of geographic information system on the framework of distribution network, in order to develop rural distribution network.
基金Projects(51278367,50878159)supported by the National Natural Science Foundation of ChinaProject(90715040)supported by the Major Research Program of National Natural Science Foundation of China
文摘Analyses of the effects of some parameters were performed to determine the admittance functions in a common two-compartment building with background porosity by the imposed excitation method.Variations of the magnification factors of fluctuating internal pressures were analyzed using 96 model cases under random fluctuating external pressure,and then corresponding design equations were fitted.The results show that the Helmholtz resonance peaks of the admittance functions in both compartments increase with increasing the area of windward or partition wall opening.With increasing the volume of the compartment with an external opening,the resonance peak in this compartment at the higher Helmholtz frequency significantly decreases,at the same time,the resonance peak in the other compartment at the lower Helmholtz frequency also decreases.With increasing the volume of the compartment with background porosity,both resonance peaks in this compartment at the lower and higher Helmholtz frequencies decrease,meanwhile,the resonance peak at the lower Helmholtz frequency for the other compartment also decreases,whereas the resonance peak at the higher Helmholtz frequency increases.Both resonance peaks of the admittance functions in the two compartments decrease with increasing the amplitude of fluctuating external pressure coefficients or reference wind speed.
文摘In this research,mechanical stress,static strain and deformation analyses of a cylindrical pressure vessel subjected to mechanical loads are presented.The kinematic relations are developed based on higherorder sinusoidal shear deformation theory.Thickness stretching formulation is accounted for more accurate analysis.The total transverse deflection is divided into bending,shear and thickness stretching parts in which the third term is responsible for change of deflection along the thickness direction.The axisymmetric formulations are derived through principle of virtual work.A parametric study is presented to investigate variation of stress and strain components along the thickness and longitudinal directions.To explore effect of thickness stretching model on the static results,a comparison between the present results with the available results of literature is presented.As an important output,effect of micro-scale parameter is studied on the static stress and strain distribution.
文摘Studies on the cold-responsive genes and cold signaling of woody species drop far behind in comparison to herbaceous plants.Due to similar lignified structure,perennial characteristic,and enhanced tolerance,it seems much easier to find strongly antifreeze genes and obtain effective results in transgenic woody plants.In this study,Ammopiptanthus mongolicus,an evergreen,broadleaf and cold-resist leguminous shrub growing in the desert of Inner Mongolia,was used as a material for low-temperature induced gene isolation.Through differential expression analysis induced by low-temperature,thirteen up-regulated cDNAs were identified.One of them,AmEBP1,(accession number:DQ519359)confers enhanced cold-tolerance to both transgenic E.coli and transgenic Arabidopsis.Results suggest that AmEBP1 can stimulate the synthesis of ribosome and the dephosphyration of the α-subunit of initiation factor 2(eIF2α),and subsequently promote the translation process.By which the transgenic plants obtained increased cold-resistant ability.
文摘Geometry optimization of p-C_(6)H_(4)-connected cyclo[20]carbon(p-C_(6)H_(4)-C_(20))was carried out at M062X/6-311G(d,p)level,three kinds of bond orders(Mayer,Laplacian,and Wiberg),electron-hole distributions,localized orbital locators(LOL),and infrared(IR)spectrum were also performed at the same level.Based on TD-DFT M062X/6-311G(d,p)method,the first 20 excited states and ultraviolet(UV)spectra of p-C_(6)H_(4)-C_(20) were calculated.Calculation results of π-electron delocalization analyses prove thatπ-electron delocalization of p-C_(6)H_(4)-C_(20) is more likely to occur on shorter C-C bonds rather than longer C-C bonds,and inside/outside of the ring plane rather than above/below the ring plane.Two absorption peaks of p-C_(6)H_(4)-C_(20) locate at about 319 nm and 236 nm,respectively.