Silicon(Si)diffraction microlens arrays are usually used to integrating with infrared focal plane arrays(IRFPAs)to improve their performance.The errors of lithography are unavoidable in the process of the Si diffrac-t...Silicon(Si)diffraction microlens arrays are usually used to integrating with infrared focal plane arrays(IRFPAs)to improve their performance.The errors of lithography are unavoidable in the process of the Si diffrac-tion microlens arrays preparation in the conventional engraving method.It has a serious impact on its performance and subsequent applications.In response to the problem of errors of Si diffraction microlens arrays in the conven-tional method,a novel self-alignment method for high precision Si diffraction microlens arrays preparation is pro-posed.The accuracy of the Si diffractive microlens arrays preparation is determined by the accuracy of the first li-thography mask in the novel self-alignment method.In the subsequent etching,the etched area will be protected by the mask layer and the sacrifice layer or the protective layer.The unprotection area is carved to effectively block the non-etching areas,accurately etch the etching area required,and solve the problem of errors.The high precision Si diffraction microlens arrays are obtained by the novel self-alignment method and the diffraction effi-ciency could reach 92.6%.After integrating with IRFPAs,the average blackbody responsity increased by 8.3%,and the average blackbody detectivity increased by 10.3%.It indicates that the Si diffraction microlens arrays can improve the filling factor and reduce crosstalk of IRFPAs through convergence,thereby improving the perfor-mance of the IRFPAs.The results are of great reference significance for improving their performance through opti-mizing the preparation level of micro nano devices.展开更多
Genetic variations of three species from primary parent （OI Q,SIS Q,Kona Bay Q） and their first filial generation （OI Z,SIS Z,Kona Bay Z） of Litopenaeus vannamei were detected using microsatellite marker technique...Genetic variations of three species from primary parent （OI Q,SIS Q,Kona Bay Q） and their first filial generation （OI Z,SIS Z,Kona Bay Z） of Litopenaeus vannamei were detected using microsatellite marker technique.The amplified products of genomic DNA with 8 microsatellite makers indicated that 8 loci presents polymorphism,the number of total alleles were 28 in 6 species;the number of allele of every loci was 2 to 6;mean allele number （Na） was 3.5;expected heterozygosity value （He） were higher than observed heterozygosity value （Ho）;mean polymorphism information content （PIC） ranged from 0.479 4 to 0.769 9,which showed these 8 loci posses relatively high information content.Through analysis of genetic structure in primary parent and their first filial,allele and effective allele number,observed heterozygosity and expected heterozygosity values and mean polymorphism information content （PIC） in filial generation were little lower than their primary parents.However,genetic diversity of filial generation is not influenced,and still maintains a good heritability.展开更多
For the high altitude cruising flight phase of a hypersonic cruise missile （HCM）, a relative motion mod- el between the missile and the target is established by defining virtual target and combining the theory of th...For the high altitude cruising flight phase of a hypersonic cruise missile （HCM）, a relative motion mod- el between the missile and the target is established by defining virtual target and combining the theory of the dif- ferential geometry with missile motion equations. Based on the model, the motion between the missile and the tar- get is considered as a single target differential game problem, and a new open-loop differential game midcourse guidance law （DGMGL） is deduced by solving the corresponding Hamiltonian Function. Meanwhile, a new struc- ture of a closed-loop DGMGL is presented and the training data for back propagation neural network （BPNN） are designed. By combining the theory of BPNN with the open-loop DGMGL obtained above, the law intelligence is realized. Finally, simulation is carried out and the validity of the law is testified.展开更多
Aim To develop a physical and mathematical model related to micropore para- meters of steady-state convective combustion of micropore propellants(MPP). Methods The micropore parameters were measured by WXT-88 mage ana...Aim To develop a physical and mathematical model related to micropore para- meters of steady-state convective combustion of micropore propellants(MPP). Methods The micropore parameters were measured by WXT-88 mage analysis apparatus and the convective combustion characteristic of MPP was measured by a large volume closed bomb, respectively. Rasults Statistical physical model of burning in the micropore and granular burning were developed. The burning rate equation of steady-state convective combustion of MPP was obtained. Conclusions This model correlates the convective burning rate with micropores para- meters for the first time,and the calculating values of convective burning rate are in agreement with test results.The model also can be used to estimate the effects of microporous parame- ters, basic mass burning rate, MPP density and pressure in combustion chamber on the convective combustion characteristics of MPP.展开更多
New developments have been made on the applications of the differential quadrature(DQ)method to analysis of structural problems recently.The method is used to obtain solutions of large deflections, membrane and bendin...New developments have been made on the applications of the differential quadrature(DQ)method to analysis of structural problems recently.The method is used to obtain solutions of large deflections, membrane and bending stresses of circular plates with movable and immovable edges under uniform pressures or a central point load.The shortcomings existing in the earlier analysis by the DQ method have been overcome by a new approach in applying the boundary conditions. The accuracy and the efficiency of the newly developed method for solving nonlinear problems are demonstrated.展开更多
The ductility and plastic asymmetry of an as-annealed magnesium alloy plate were studied in compression through combined process of torsion and subsequent annealing by optical microscope and EBSD. The yield strength...The ductility and plastic asymmetry of an as-annealed magnesium alloy plate were studied in compression through combined process of torsion and subsequent annealing by optical microscope and EBSD. The yield strength（YS） and ultimate compression strength（UCS） as well as the compression ductility（CD） were simultaneously raised by prior torsion at room temperature. The CD was further enhanced by subsequent annealing. Also, the torqued sample followed by annealing experienced a rising CD with the increase in prior strain, leading to the maximum true strain of 0.279, which is twice that of the as-annealed original one. The sample showed a largely reduced tension-compression yield asymmetry by subjecting to pre-torsion alone or combined with a subsequent annealing. The enhanced ductility and reduced asymmetry are attributed to the development of a gradient microstructure with refined grains, and also randomization of the weakened texture due to torsion and subsequent annealing.展开更多
Technological parameters of asymmetric cast-rolling under multi-energy field were investigated on horizontal twin roll caster（d400 mm×500 mm）, and their effects on structures and properties of 1050 strips were ...Technological parameters of asymmetric cast-rolling under multi-energy field were investigated on horizontal twin roll caster（d400 mm×500 mm）, and their effects on structures and properties of 1050 strips were analyzed by comparing with traditional cast-rolling. Results show that when length of cast-rolling area is 70 mm, melt temperature of head box is 670 °C, cast rolling speed is 1.3 m/min, exciting current is 10 A, center frequency is（13±1） Hz, ultrasonic power is 200 W and ultrasonic frequency is（20±0.2） kHz, the 1050 strip with the best microstructure can be prepared successfully; its center segregated layer disappears; the average grain size is reduced by about 40%; the crystal grains are distributed evenly; micro segregation decreases obviously; the precipitated phases are distributed along the grain boundaries evenly; and the tensile strength, yield strength, elongation and micro-hardness of cast-rolled strip are improved by 22.6%, 23.66%, 38.75% and 9.90%, respectively.展开更多
This paper studies the numerical simulation for semiconductor devices and discusses the software design of the simulation system. Our focus is on the deep submicron device simulation for BJT, MOSFET, heterojunction bi...This paper studies the numerical simulation for semiconductor devices and discusses the software design of the simulation system. Our focus is on the deep submicron device simulation for BJT, MOSFET, heterojunction bipolar transistors (HBT), etc. So the object oriented technology for software design and its realization is used to make the system easy to implement, maintain and extend. Besides the discussion of simulation and software system design, this paper introduces a device simulator SMDS and its parallel extension under local network environment using CORBA technology.展开更多
This paper presents a new method to seek the conserved quantity from a Lie symmetry without using either Lagrangians or Hamiltonians for nonholonomic systems. The differential equations of motion of the systems are es...This paper presents a new method to seek the conserved quantity from a Lie symmetry without using either Lagrangians or Hamiltonians for nonholonomic systems. The differential equations of motion of the systems are established. The definition of the Lie symmetrical transformations of the systems is given, which only depends upon the infinitesimal transformations of groups for the generalized coordinates. The conserved quantity is directly constructed in terms of the Lie symmetry of the systems. The condition under which the Lie symmetry can lead to the conserved quantity and the form of the conserved quantity are obtained. Finally, an example is given to illustrate the application of the result.展开更多
J.Kaplan and J.Yorke's method is extended to establish the exis- tence of many and infinitely many periodic solutions for the DDEs (t) =±f(x(t-1))±f(x(t-2))and (t)=±f(x(t-1).
An InP-based single-heterojunction bipolar transistor （SHBT） with base μ-bndge and emitter air-bridge is reported. Because those bridges reduce parasitic capacitance greatly, the cutoff frequency fT of the 2μm ...An InP-based single-heterojunction bipolar transistor （SHBT） with base μ-bndge and emitter air-bridge is reported. Because those bridges reduce parasitic capacitance greatly, the cutoff frequency fT of the 2μm ×12.5μm InP SHBT without de-embedding reaches 178GHz. It is critical in high-speed low power applications,such as OEIC receivers and analog-to-digital converters.展开更多
[Objective] This study aimed to analyze the contents of trace elements in potatoes from different production areas in Qinghai Province. [Method] By flame atomic absorption spectrometry （FAAS）, the contents of variou...[Objective] This study aimed to analyze the contents of trace elements in potatoes from different production areas in Qinghai Province. [Method] By flame atomic absorption spectrometry （FAAS）, the contents of various trace elements in potatoes were determined. [Result] Potatoes contain abundant trace elements such as Cu, Zn, Fe, Mn, Ca, K and Mg. To be specific, the contents of Ca, K and Mg were relatively high. [Conclusion] By using FAAS, the relative standard deviation was 1.17%-2.75% and the recovery rate was 97%-99.5%, indicating accurate and reli-able results with high precision.展开更多
In classical nonlinear programming, it is a general method of developing optimality conditions that a nonlinear programming problem is linearized as a linear programming problem by using first order approximations of ...In classical nonlinear programming, it is a general method of developing optimality conditions that a nonlinear programming problem is linearized as a linear programming problem by using first order approximations of the functions at a given feasible point. The linearized procedure for differentiable nonlinear programming problems can be naturally generalized to the quasi differential case. As in classical case so called constraint qualifications have to be imposed on the constraint functions to guarantee that for a given local minimizer of the original problem the nullvector is an optimal solution of the corresponding 'quasilinearized' problem. In this paper, constraint qualifications for inequality constrained quasi differentiable programming problems of type min {f(x)|g(x)≤0} are considered, where f and g are qusidifferentiable functions in the sense of Demyanov. Various constraint qualifications for this problem are presented and a new one is proposed. The relations among these conditions are investigated. Moreover, a Wolf dual problem for this problem is introduced, and the corresponding dual theorems are given.展开更多
基金Supported by the National Natural Science Foundation of China(NSFC 62105100)the National Key research and development program in the 14th five year plan(2021YFA1200700)。
文摘Silicon(Si)diffraction microlens arrays are usually used to integrating with infrared focal plane arrays(IRFPAs)to improve their performance.The errors of lithography are unavoidable in the process of the Si diffrac-tion microlens arrays preparation in the conventional engraving method.It has a serious impact on its performance and subsequent applications.In response to the problem of errors of Si diffraction microlens arrays in the conven-tional method,a novel self-alignment method for high precision Si diffraction microlens arrays preparation is pro-posed.The accuracy of the Si diffractive microlens arrays preparation is determined by the accuracy of the first li-thography mask in the novel self-alignment method.In the subsequent etching,the etched area will be protected by the mask layer and the sacrifice layer or the protective layer.The unprotection area is carved to effectively block the non-etching areas,accurately etch the etching area required,and solve the problem of errors.The high precision Si diffraction microlens arrays are obtained by the novel self-alignment method and the diffraction effi-ciency could reach 92.6%.After integrating with IRFPAs,the average blackbody responsity increased by 8.3%,and the average blackbody detectivity increased by 10.3%.It indicates that the Si diffraction microlens arrays can improve the filling factor and reduce crosstalk of IRFPAs through convergence,thereby improving the perfor-mance of the IRFPAs.The results are of great reference significance for improving their performance through opti-mizing the preparation level of micro nano devices.
基金Supported by Technology Innovation Projects from Science and Tech-nology Department of Guangdong Province (2008A023700011)~~
文摘Genetic variations of three species from primary parent （OI Q,SIS Q,Kona Bay Q） and their first filial generation （OI Z,SIS Z,Kona Bay Z） of Litopenaeus vannamei were detected using microsatellite marker technique.The amplified products of genomic DNA with 8 microsatellite makers indicated that 8 loci presents polymorphism,the number of total alleles were 28 in 6 species;the number of allele of every loci was 2 to 6;mean allele number （Na） was 3.5;expected heterozygosity value （He） were higher than observed heterozygosity value （Ho）;mean polymorphism information content （PIC） ranged from 0.479 4 to 0.769 9,which showed these 8 loci posses relatively high information content.Through analysis of genetic structure in primary parent and their first filial,allele and effective allele number,observed heterozygosity and expected heterozygosity values and mean polymorphism information content （PIC） in filial generation were little lower than their primary parents.However,genetic diversity of filial generation is not influenced,and still maintains a good heritability.
文摘For the high altitude cruising flight phase of a hypersonic cruise missile （HCM）, a relative motion mod- el between the missile and the target is established by defining virtual target and combining the theory of the dif- ferential geometry with missile motion equations. Based on the model, the motion between the missile and the tar- get is considered as a single target differential game problem, and a new open-loop differential game midcourse guidance law （DGMGL） is deduced by solving the corresponding Hamiltonian Function. Meanwhile, a new struc- ture of a closed-loop DGMGL is presented and the training data for back propagation neural network （BPNN） are designed. By combining the theory of BPNN with the open-loop DGMGL obtained above, the law intelligence is realized. Finally, simulation is carried out and the validity of the law is testified.
文摘Aim To develop a physical and mathematical model related to micropore para- meters of steady-state convective combustion of micropore propellants(MPP). Methods The micropore parameters were measured by WXT-88 mage analysis apparatus and the convective combustion characteristic of MPP was measured by a large volume closed bomb, respectively. Rasults Statistical physical model of burning in the micropore and granular burning were developed. The burning rate equation of steady-state convective combustion of MPP was obtained. Conclusions This model correlates the convective burning rate with micropores para- meters for the first time,and the calculating values of convective burning rate are in agreement with test results.The model also can be used to estimate the effects of microporous parame- ters, basic mass burning rate, MPP density and pressure in combustion chamber on the convective combustion characteristics of MPP.
文摘New developments have been made on the applications of the differential quadrature(DQ)method to analysis of structural problems recently.The method is used to obtain solutions of large deflections, membrane and bending stresses of circular plates with movable and immovable edges under uniform pressures or a central point load.The shortcomings existing in the earlier analysis by the DQ method have been overcome by a new approach in applying the boundary conditions. The accuracy and the efficiency of the newly developed method for solving nonlinear problems are demonstrated.
基金Project(51474241)supported by the National Natural Science Foundation of ChinaProject(2013CB632204)supported by the National Basic Research Program of China
文摘The ductility and plastic asymmetry of an as-annealed magnesium alloy plate were studied in compression through combined process of torsion and subsequent annealing by optical microscope and EBSD. The yield strength（YS） and ultimate compression strength（UCS） as well as the compression ductility（CD） were simultaneously raised by prior torsion at room temperature. The CD was further enhanced by subsequent annealing. Also, the torqued sample followed by annealing experienced a rising CD with the increase in prior strain, leading to the maximum true strain of 0.279, which is twice that of the as-annealed original one. The sample showed a largely reduced tension-compression yield asymmetry by subjecting to pre-torsion alone or combined with a subsequent annealing. The enhanced ductility and reduced asymmetry are attributed to the development of a gradient microstructure with refined grains, and also randomization of the weakened texture due to torsion and subsequent annealing.
基金Project(2014CB046702)supported by National Basic Research Program of China
文摘Technological parameters of asymmetric cast-rolling under multi-energy field were investigated on horizontal twin roll caster（d400 mm×500 mm）, and their effects on structures and properties of 1050 strips were analyzed by comparing with traditional cast-rolling. Results show that when length of cast-rolling area is 70 mm, melt temperature of head box is 670 °C, cast rolling speed is 1.3 m/min, exciting current is 10 A, center frequency is（13±1） Hz, ultrasonic power is 200 W and ultrasonic frequency is（20±0.2） kHz, the 1050 strip with the best microstructure can be prepared successfully; its center segregated layer disappears; the average grain size is reduced by about 40%; the crystal grains are distributed evenly; micro segregation decreases obviously; the precipitated phases are distributed along the grain boundaries evenly; and the tensile strength, yield strength, elongation and micro-hardness of cast-rolled strip are improved by 22.6%, 23.66%, 38.75% and 9.90%, respectively.
文摘This paper studies the numerical simulation for semiconductor devices and discusses the software design of the simulation system. Our focus is on the deep submicron device simulation for BJT, MOSFET, heterojunction bipolar transistors (HBT), etc. So the object oriented technology for software design and its realization is used to make the system easy to implement, maintain and extend. Besides the discussion of simulation and software system design, this paper introduces a device simulator SMDS and its parallel extension under local network environment using CORBA technology.
文摘This paper presents a new method to seek the conserved quantity from a Lie symmetry without using either Lagrangians or Hamiltonians for nonholonomic systems. The differential equations of motion of the systems are established. The definition of the Lie symmetrical transformations of the systems is given, which only depends upon the infinitesimal transformations of groups for the generalized coordinates. The conserved quantity is directly constructed in terms of the Lie symmetry of the systems. The condition under which the Lie symmetry can lead to the conserved quantity and the form of the conserved quantity are obtained. Finally, an example is given to illustrate the application of the result.
文摘J.Kaplan and J.Yorke's method is extended to establish the exis- tence of many and infinitely many periodic solutions for the DDEs (t) =±f(x(t-1))±f(x(t-2))and (t)=±f(x(t-1).
文摘An InP-based single-heterojunction bipolar transistor （SHBT） with base μ-bndge and emitter air-bridge is reported. Because those bridges reduce parasitic capacitance greatly, the cutoff frequency fT of the 2μm ×12.5μm InP SHBT without de-embedding reaches 178GHz. It is critical in high-speed low power applications,such as OEIC receivers and analog-to-digital converters.
文摘[Objective] This study aimed to analyze the contents of trace elements in potatoes from different production areas in Qinghai Province. [Method] By flame atomic absorption spectrometry （FAAS）, the contents of various trace elements in potatoes were determined. [Result] Potatoes contain abundant trace elements such as Cu, Zn, Fe, Mn, Ca, K and Mg. To be specific, the contents of Ca, K and Mg were relatively high. [Conclusion] By using FAAS, the relative standard deviation was 1.17%-2.75% and the recovery rate was 97%-99.5%, indicating accurate and reli-able results with high precision.
文摘In classical nonlinear programming, it is a general method of developing optimality conditions that a nonlinear programming problem is linearized as a linear programming problem by using first order approximations of the functions at a given feasible point. The linearized procedure for differentiable nonlinear programming problems can be naturally generalized to the quasi differential case. As in classical case so called constraint qualifications have to be imposed on the constraint functions to guarantee that for a given local minimizer of the original problem the nullvector is an optimal solution of the corresponding 'quasilinearized' problem. In this paper, constraint qualifications for inequality constrained quasi differentiable programming problems of type min {f(x)|g(x)≤0} are considered, where f and g are qusidifferentiable functions in the sense of Demyanov. Various constraint qualifications for this problem are presented and a new one is proposed. The relations among these conditions are investigated. Moreover, a Wolf dual problem for this problem is introduced, and the corresponding dual theorems are given.
