Let Q n denote the class of all polynomials p(z) nonvanishing in the unit disk with deg p≤n and p (0)=1, and let W n denote the class of all polynomials s(z) satisfying deg s≤n and for all...Let Q n denote the class of all polynomials p(z) nonvanishing in the unit disk with deg p≤n and p (0)=1, and let W n denote the class of all polynomials s(z) satisfying deg s≤n and for all p∈Q n, s*p∈Q n , where * denotes the Hadamard product. Some properties for W n and Q n are obtained.展开更多
The distributed Lagrange multiplier/fictitious domain(DLM/FD)-mixed finite element method is developed and analyzed in this paper for a transient Stokes interface problem with jump coefficients.The semi-and fully disc...The distributed Lagrange multiplier/fictitious domain(DLM/FD)-mixed finite element method is developed and analyzed in this paper for a transient Stokes interface problem with jump coefficients.The semi-and fully discrete DLM/FD-mixed finite element scheme are developed for the first time for this problem with a moving interface,where the arbitrary Lagrangian-Eulerian(ALE)technique is employed to deal with the moving and immersed subdomain.Stability and optimal convergence properties are obtained for both schemes.Numerical experiments are carried out for different scenarios of jump coefficients,and all theoretical results are validated.展开更多
The asymptotic stability of a discrete logistic model with random growth coefficient is studied in this paper. Firstly, the discrete logistic model with random growth coefficient is built and reduced into its determin...The asymptotic stability of a discrete logistic model with random growth coefficient is studied in this paper. Firstly, the discrete logistic model with random growth coefficient is built and reduced into its deterministic equivalent system by orthogonal polynomial approximation. Then, the linear stability theory and the Jury criterion of nonlinear deterministic discrete systems are applied to the equivalent one. At last, by mathematical analysis, we find that the parameter interval for asymptotic stability of nontrivial equilibrium in stochastic logistic system gets smaller as the random intensity or statistical parameters of random variable is increased and the random parameter’s influence on asymptotic stability in stochastic logistic system becomes prominent.展开更多
Urban land-use modeling has gained increased attention as a research topic over the last decade. This has been attributed to advances in remote sensing and computing technology that now can process several models simu...Urban land-use modeling has gained increased attention as a research topic over the last decade. This has been attributed to advances in remote sensing and computing technology that now can process several models simultaneously at regional and local levels. In this research we implemented a cellular automata (CA) urban growth model (UGM) integrated in the XULU modeling frame-work (eXtendable Unified Land Use Modeling Platform). We used multi-temporal Landsat satellite image sets for 1986, 2000 and 2010 to map urban land-use in Nairobi. We also tested the spatial effects of varying model coefficients. This approach improved model performance and aided in understanding the particular urban land-use system dynamics operating in our Nairobi study area. The UGM was calibrated for Nairobi and predicted development was derived for the city for the year 2030 when Kenya plans to attain Vision 2030. Observed land-use changes in urban areas were compared to the results of UGM modeling for the year 2010. The results indicate that varying the UGM model coefficients simulates urban growth in different directions and magnitudes. This approach is useful to planners and policy makers because the model outputs can identify specific areas within the urban complex which will require infrastructure and amenities in order to realize sustainable development.展开更多
The objective of this study is to analyze a chemostat model of very simple type with the Haldane expression of growth rate and a variable yield coefficient. The proposed modified model is analyzed qualitatively and qu...The objective of this study is to analyze a chemostat model of very simple type with the Haldane expression of growth rate and a variable yield coefficient. The proposed modified model is analyzed qualitatively and quantitatively. Analytic conditions for stability and optimality are determined for washout and no washout equilibrium solutions. One of the main focuses of the study is to determine parameter values for which Hopf Bifurcations occur in a bioreactor. It has been shown that the maximum stable non-washout equilibrium exits at a residence time under suitable parameter values. Hopf bifurcation is observed at three different conditions of the parameters.展开更多
DSP operation in a Biomedical related therapeutic hardware need to beperformed with high accuracy and with high speed. Portable DSP hardware’s likepulse/heart beat detectors must perform with reduced operational powe...DSP operation in a Biomedical related therapeutic hardware need to beperformed with high accuracy and with high speed. Portable DSP hardware’s likepulse/heart beat detectors must perform with reduced operational power due to lack ofconventional power sources. This work proposes a hybrid biomedical hardware chip inwhich the speed and power utilization factors are greatly improved. Multipliers are thecore operational unit of any DSP SoC. This work proposes a LUT based unsignedmultiplication which is proven to be efficient in terms of high operating speed. For n bitinput multiplication n*n memory array of 2 n bit size is required to memorize all thepossible input and output combination. Various literature works claims to be achieve highspeed multiplication with reduced LUT size by integrating a barrel shifter mechanism.This paper work address this problem, by reworking the multiplier architecture with aparallel operating pre-processing unit which used to change the multiplier and multiplicandorder with respect to the number of computational addition and subtraction stages required.Along with LUT multiplier a low power bus encoding scheme is integrated to limit the powerconstraint of the on chip DSP unit. This paper address both the speed and power optimizationtechniques and tested with various FPGA device families.展开更多
This paper deals with some initial-oblique derivative boundary value problems for nonlinear nondivergent parabolic systems of several second order equations with measurable coefficients in multiply connected domains. ...This paper deals with some initial-oblique derivative boundary value problems for nonlinear nondivergent parabolic systems of several second order equations with measurable coefficients in multiply connected domains. Firstly, a priori estimates of solutions for the initial-boundary value problems are given, and then by using the above estimates of solutions and the Leray-Schauder theorem, the existence and uniqueness of solutions for the problems are proved.展开更多
In this paper we consider the class ∑^*(p,α,β,k,c) consisting of analytic functions with negativecoefficients and fixed second coefficient. The object of the present paper is to give coefficient estimates, conve...In this paper we consider the class ∑^*(p,α,β,k,c) consisting of analytic functions with negativecoefficients and fixed second coefficient. The object of the present paper is to give coefficient estimates, convex linear combinations, some distortion theorems and radii of starlikeness and convexity for f(z) in the class ∑^*(p,α,β,k,c) .展开更多
When current passes through the solid-liquid interface, the growth rate of crystal, solid-liquid interface energy and radius of curvature at dendritic tip will change. Based on this fact, the theoretical relation betw...When current passes through the solid-liquid interface, the growth rate of crystal, solid-liquid interface energy and radius of curvature at dendritic tip will change. Based on this fact, the theoretical relation between the distribution of solute at solid-liquid interface and current density was established, and the effect of current on the distribution coefficient of solute through effecting the rate of crystal growth, the solid-liquid interface energy and the radius of curvature at the dendritic tip was discussed. The results show that as the current density increases, the distribution coefficient of solute tends to rise in a whole, and when the former is larger than about 400 A/cm 2, the latter varies significantly.展开更多
Background: Analysing and modelling plant growth is an important interdisciplinary field of plant science. The use of relative growth rates, involving the analysis of plant growth relative to plant size, has more or ...Background: Analysing and modelling plant growth is an important interdisciplinary field of plant science. The use of relative growth rates, involving the analysis of plant growth relative to plant size, has more or less independently emerged in different research groups and at different times and has provided powerful tools for assessing the growth performance and growth efficiency of plants and plant populations. In this paper, we explore how these isolated methods can be combined to form a consistent methodology for modelling relative growth rates. Methods: We review and combine existing methods of analysing and modelling relative growth rates and apply a combination of methods to Sitka spruce (Piceo sitchensis (Bong.) Carr.) stem-analysis data from North Wales (UK) and British Douglas fir (Pseudotsugd menziesii (Mirb.) Franco) yield table data. Results: The results indicate that, by combining the approaches of different plant-growth analysis laboratories and using them simultaneously, we can advance and standardise the concept of relative plant growth. Particularly the growth multiplier plays an important role in modelling relative growth rates. Another useful technique has been the recent introduction of size-standardised relative growth rates. Conclusions: Modelling relative growth rates mainly serves two purposes, 1) an improved analysis of growth performance and efficiency and 2) the prediction of future or past growth rates. This makes the concept of relative growth ideally suited to growth reconstruction as required in dendrochronology, climate change and forest decline research and for interdisciplinary research projects beyond the realm of plant science.展开更多
Low thermal expansion superalloys have been used for a number of years in a variety of applications, including gas turbine engines. The low thermal expansion characteristics of the most widely used class of materials ...Low thermal expansion superalloys have been used for a number of years in a variety of applications, including gas turbine engines. The low thermal expansion characteristics of the most widely used class of materials are derived from the ferromagnetic characteristics of Ni, Fe, and Co-based austenitic matrices containing little or no Cr.Alloy developments have been aimed at improving the oxidation resistance and stress accelerated grain boundary oxygen (SAGBO) attack.INCONEL alloy 783 is an oxidation resistant, low coefficient of thermal expansion superalloy developed for gas turbine applications. Alloy 783 represents a culmination in the development, of an alloy system with very high alumtnum content that, in addition to forming γ′,causes βaluminide phase precipitation in the austenitic matrix.This type of structure can be processed to resist both SAGBO and general oxidation,while providing low thermal expansion and useful mechanical properties up to 700℃.Key aspects of the alloy's development are presented.展开更多
Within the framework of endogenous growth theory,the dynamic relation between age structure of population and resident consumption was studied,and explicit relation between resident consumption and dependency coeffici...Within the framework of endogenous growth theory,the dynamic relation between age structure of population and resident consumption was studied,and explicit relation between resident consumption and dependency coefficient was obtained through Hamiltonian function method. Then,an empirical study was carried out based on panel data of 31 provinces of China in 2000-2013. The study gave following results: there is negative correlation between child dependency coefficient and resident consumption and there is positive correlation between elderly dependency coefficient and resident consumption; urbanization level weakens the negative effect of child dependency coefficient on resident consumption but it increases the positive effect of elderly dependency coefficient on resident consumption; social expenditure weakens the negative effect of child dependency coefficient on resident consumption,but it intensifies positive effect of elderly dependency coefficient on resident consumption. These results indicate that current population structure of China is favorable for growth of resident consumption demand,but in such aging population structure,economic development may lose demographic dividends.展开更多
The exceptionally large individual growth variation has been previously recognized in several sea cucumber cohorts. However, there is a lack of information regarding the mechanism of such individual differences. In th...The exceptionally large individual growth variation has been previously recognized in several sea cucumber cohorts. However, there is a lack of information regarding the mechanism of such individual differences. In this study, the sea cucumber Apostichopusjaponicus (Selenka) was reared individually in order to eliminate possible effects of social interaction, stocking density, etc. The results showed that there were substantial differences in growth among the sea cucumber individuals during the 100-day experiment. The special growth rate of the sea cucumber individuals differed by up to three folds (from 0.40% to 1.01%), and the coefficient of variation in body weight increased from 12.04% to 40.51%. The final wet body weight, food intake and food conversion efficiency for each sea cucumber were generally positively correlated with their initial wet body weight (P〈0.05). Energy budget of the animals showed that the food energy spent on respiration was much greater (about four folds) but energy deposited for growth was much less for (initially) smaller than for larger A. japonicus. The present result implies that there are obvious genetic differences among the sea cucumber individuals, largely accounting for the individual growth variation of the cohort sea cucumber. These results will provide some basic data for promoting selective breeding and fanning of the sea cucumber.展开更多
In the paper, we characterize the coefficient multiplier spaces of mixed norm spaces (Hp,q((?)1),Hu,v((?)2)) for the values of p, q, u, v in three cases: (i)0<p≤u≤∞, 0 < q≤min(1,v)≤frr. (ii) v =∞,0<p≤...In the paper, we characterize the coefficient multiplier spaces of mixed norm spaces (Hp,q((?)1),Hu,v((?)2)) for the values of p, q, u, v in three cases: (i)0<p≤u≤∞, 0 < q≤min(1,v)≤frr. (ii) v =∞,0<p≤u≤∞, 1≤u, q≤∞. (iii) 1≤v≤2≤q≤∞, and 0<p≤u≤∞or 1≤p, u≤∞. The first case extends the result of Blasco, Jevtic, and Pavlovic in one variable. The third case generalizes partly the results of Jevtic, Jovanovic, and Wojtaszczyk to higher dimensions.展开更多
Based on the assumptions of "information transfer" and "information creation", this paper educes the multiplied growth mechanism of network information: that the gross quantity of network information (Im) is ab...Based on the assumptions of "information transfer" and "information creation", this paper educes the multiplied growth mechanism of network information: that the gross quantity of network information (Im) is about n times as much as the quantity of real network information (Ir). According to this theoretical model, we give a uniform explanation to all kinds of information growth models in existence, and put forward some proposals, such as "forbidding information transfer" and "building up the central information base", to control the repeated information flooding on the network and facilitate the full use of network information.展开更多
The InAs/AlSb heterostructures with step-graded GaAsxSb1-x metamorphic buffer layers grown on Si substrates by molecular beam epitaxy are studied. The step-graded GaAsxSb1-x metamorphic buffer layers are used to relax...The InAs/AlSb heterostructures with step-graded GaAsxSb1-x metamorphic buffer layers grown on Si substrates by molecular beam epitaxy are studied. The step-graded GaAsxSb1-x metamorphic buffer layers are used to relax the strain and block defects at each interface of the layers. Meanwhile, adding Sb to GaAs is also beneficial to suppressing the formation of dislocations in the subsequent materials. The influences of the growth temperature of the step-graded GaAsxSb1-x metamorphic buffer layer on the electron mobility and surface topography are investigated for a series of samples. Based on the atomic force microscopy(AFM), high resolution x-ray diffraction(HRXRD), reciprocal space map(RSM), and Hall measurements, the crystal quality and composition of GaAsxSb1-x layer are seen to strongly depend on growth temperature while keeping the Ga growth rate and V/III ratio constant. The results show that the highest electron mobility is 10270 cm2/V·s and the roughness is 4.3 nm for the step-graded GaAsxSb1-x metamorphic buffer layer grown at a temperature of 410℃.展开更多
Let g and h be two transcendental entire functions. Suppose that the Fatou set F(goh) contains multiply connected components. In this article, we will consider the growth of the functions g and h.
This paper first studies the relations between the growth and the coefficients of Dirichlet series of zero order in the whole plane,and further proves that the growth of random entire functions defined by random Diri...This paper first studies the relations between the growth and the coefficients of Dirichlet series of zero order in the whole plane,and further proves that the growth of random entire functions defined by random Dirichlet series of zero order in every horizotal straight lines is almost surely equal to the growth of entire functions defined by their corresponding Dirichlet series.展开更多
Juvenile turbot (Scophthalmus maximus) the initial stock densities at 0.28, 0.87, 1.12, 1.16, 2.75 were reared in five different experiment groups in kg/m^2 respectively for the study of the density effect on growth...Juvenile turbot (Scophthalmus maximus) the initial stock densities at 0.28, 0.87, 1.12, 1.16, 2.75 were reared in five different experiment groups in kg/m^2 respectively for the study of the density effect on growth, pigmentation and feed coefficient rate. The experiment lasted for 60 days with final stock densities at 1.91, 6.31, 8.86, 11.97, 17.67 kg/m^2 respectively. Result showed that, in the same experiment condition, the stocking density has a positive effect on growth in low density and negative in high density. The SGR (special growth rate) was 3.189, 3.304, 3.447, 3.341, and 3.087 respectively. The uniformity of weight distributing among experiment groups decreased with increasing density. The stocking density had positive effect on feed coefficient rate. Group 1 had the least feed coefficient rate 0.96, and highest at 1.25 in Group 5, the highest density group. High stocking density inhibited the growth and increased the feed coefficient rate. The stocking density had negative relationship to pigmentation improvement for whitened fish.展开更多
Based on the Tersoff potential, molecular dynamics simulations have been performed to investigate the kinetic coefficients and growth velocities of Si(100),(110),(111), and(112) planes. The sequences of the ki...Based on the Tersoff potential, molecular dynamics simulations have been performed to investigate the kinetic coefficients and growth velocities of Si(100),(110),(111), and(112) planes. The sequences of the kinetic coefficients and growth velocities are μ((100))〉 μ((110))〉 μ((112))〉 μ((111))and v((100))〉 v((110))〉 v((112))〉 v((111)), respectively, which are not consistent with the sequences of the interface energies, interplanar spacings, and melting points of the four planes. However,they agree well with the sequences of the distributions and diffusion coefficients of the melting atoms near the solid–liquid interfaces. It indicates that the atomic distributions and diffusion coefficients affected by the crystal orientations determine the anisotropic growth of silicon. The formation of stacking fault structure will further decrease the growth velocity of the Si(111) plane.展开更多
文摘Let Q n denote the class of all polynomials p(z) nonvanishing in the unit disk with deg p≤n and p (0)=1, and let W n denote the class of all polynomials s(z) satisfying deg s≤n and for all p∈Q n, s*p∈Q n , where * denotes the Hadamard product. Some properties for W n and Q n are obtained.
基金P.Sun was supported by NSF Grant DMS-1418806C.S.Zhang was partially supported by the National Key Research and Development Program of China(Grant No.2016YFB0201304)+1 种基金the Major Research Plan of National Natural Science Foundation of China(Grant Nos.91430215,91530323)the Key Research Program of Frontier Sciences of CAS.
文摘The distributed Lagrange multiplier/fictitious domain(DLM/FD)-mixed finite element method is developed and analyzed in this paper for a transient Stokes interface problem with jump coefficients.The semi-and fully discrete DLM/FD-mixed finite element scheme are developed for the first time for this problem with a moving interface,where the arbitrary Lagrangian-Eulerian(ALE)technique is employed to deal with the moving and immersed subdomain.Stability and optimal convergence properties are obtained for both schemes.Numerical experiments are carried out for different scenarios of jump coefficients,and all theoretical results are validated.
基金supported by the National Natural Science Foundation of China(11362001 and 11002001)the Natural Science Foundation of Ningxia Hui Autonomous Region(NZ12210)
文摘The asymptotic stability of a discrete logistic model with random growth coefficient is studied in this paper. Firstly, the discrete logistic model with random growth coefficient is built and reduced into its deterministic equivalent system by orthogonal polynomial approximation. Then, the linear stability theory and the Jury criterion of nonlinear deterministic discrete systems are applied to the equivalent one. At last, by mathematical analysis, we find that the parameter interval for asymptotic stability of nontrivial equilibrium in stochastic logistic system gets smaller as the random intensity or statistical parameters of random variable is increased and the random parameter’s influence on asymptotic stability in stochastic logistic system becomes prominent.
文摘Urban land-use modeling has gained increased attention as a research topic over the last decade. This has been attributed to advances in remote sensing and computing technology that now can process several models simultaneously at regional and local levels. In this research we implemented a cellular automata (CA) urban growth model (UGM) integrated in the XULU modeling frame-work (eXtendable Unified Land Use Modeling Platform). We used multi-temporal Landsat satellite image sets for 1986, 2000 and 2010 to map urban land-use in Nairobi. We also tested the spatial effects of varying model coefficients. This approach improved model performance and aided in understanding the particular urban land-use system dynamics operating in our Nairobi study area. The UGM was calibrated for Nairobi and predicted development was derived for the city for the year 2030 when Kenya plans to attain Vision 2030. Observed land-use changes in urban areas were compared to the results of UGM modeling for the year 2010. The results indicate that varying the UGM model coefficients simulates urban growth in different directions and magnitudes. This approach is useful to planners and policy makers because the model outputs can identify specific areas within the urban complex which will require infrastructure and amenities in order to realize sustainable development.
文摘The objective of this study is to analyze a chemostat model of very simple type with the Haldane expression of growth rate and a variable yield coefficient. The proposed modified model is analyzed qualitatively and quantitatively. Analytic conditions for stability and optimality are determined for washout and no washout equilibrium solutions. One of the main focuses of the study is to determine parameter values for which Hopf Bifurcations occur in a bioreactor. It has been shown that the maximum stable non-washout equilibrium exits at a residence time under suitable parameter values. Hopf bifurcation is observed at three different conditions of the parameters.
文摘DSP operation in a Biomedical related therapeutic hardware need to beperformed with high accuracy and with high speed. Portable DSP hardware’s likepulse/heart beat detectors must perform with reduced operational power due to lack ofconventional power sources. This work proposes a hybrid biomedical hardware chip inwhich the speed and power utilization factors are greatly improved. Multipliers are thecore operational unit of any DSP SoC. This work proposes a LUT based unsignedmultiplication which is proven to be efficient in terms of high operating speed. For n bitinput multiplication n*n memory array of 2 n bit size is required to memorize all thepossible input and output combination. Various literature works claims to be achieve highspeed multiplication with reduced LUT size by integrating a barrel shifter mechanism.This paper work address this problem, by reworking the multiplier architecture with aparallel operating pre-processing unit which used to change the multiplier and multiplicandorder with respect to the number of computational addition and subtraction stages required.Along with LUT multiplier a low power bus encoding scheme is integrated to limit the powerconstraint of the on chip DSP unit. This paper address both the speed and power optimizationtechniques and tested with various FPGA device families.
文摘This paper deals with some initial-oblique derivative boundary value problems for nonlinear nondivergent parabolic systems of several second order equations with measurable coefficients in multiply connected domains. Firstly, a priori estimates of solutions for the initial-boundary value problems are given, and then by using the above estimates of solutions and the Leray-Schauder theorem, the existence and uniqueness of solutions for the problems are proved.
基金The work is supported by UKM grant ST-028-2003 IRPA grant 09-02-02-80 EA208, Malysia.
文摘In this paper we consider the class ∑^*(p,α,β,k,c) consisting of analytic functions with negativecoefficients and fixed second coefficient. The object of the present paper is to give coefficient estimates, convex linear combinations, some distortion theorems and radii of starlikeness and convexity for f(z) in the class ∑^*(p,α,β,k,c) .
文摘When current passes through the solid-liquid interface, the growth rate of crystal, solid-liquid interface energy and radius of curvature at dendritic tip will change. Based on this fact, the theoretical relation between the distribution of solute at solid-liquid interface and current density was established, and the effect of current on the distribution coefficient of solute through effecting the rate of crystal growth, the solid-liquid interface energy and the radius of curvature at the dendritic tip was discussed. The results show that as the current density increases, the distribution coefficient of solute tends to rise in a whole, and when the former is larger than about 400 A/cm 2, the latter varies significantly.
文摘Background: Analysing and modelling plant growth is an important interdisciplinary field of plant science. The use of relative growth rates, involving the analysis of plant growth relative to plant size, has more or less independently emerged in different research groups and at different times and has provided powerful tools for assessing the growth performance and growth efficiency of plants and plant populations. In this paper, we explore how these isolated methods can be combined to form a consistent methodology for modelling relative growth rates. Methods: We review and combine existing methods of analysing and modelling relative growth rates and apply a combination of methods to Sitka spruce (Piceo sitchensis (Bong.) Carr.) stem-analysis data from North Wales (UK) and British Douglas fir (Pseudotsugd menziesii (Mirb.) Franco) yield table data. Results: The results indicate that, by combining the approaches of different plant-growth analysis laboratories and using them simultaneously, we can advance and standardise the concept of relative plant growth. Particularly the growth multiplier plays an important role in modelling relative growth rates. Another useful technique has been the recent introduction of size-standardised relative growth rates. Conclusions: Modelling relative growth rates mainly serves two purposes, 1) an improved analysis of growth performance and efficiency and 2) the prediction of future or past growth rates. This makes the concept of relative growth ideally suited to growth reconstruction as required in dendrochronology, climate change and forest decline research and for interdisciplinary research projects beyond the realm of plant science.
文摘Low thermal expansion superalloys have been used for a number of years in a variety of applications, including gas turbine engines. The low thermal expansion characteristics of the most widely used class of materials are derived from the ferromagnetic characteristics of Ni, Fe, and Co-based austenitic matrices containing little or no Cr.Alloy developments have been aimed at improving the oxidation resistance and stress accelerated grain boundary oxygen (SAGBO) attack.INCONEL alloy 783 is an oxidation resistant, low coefficient of thermal expansion superalloy developed for gas turbine applications. Alloy 783 represents a culmination in the development, of an alloy system with very high alumtnum content that, in addition to forming γ′,causes βaluminide phase precipitation in the austenitic matrix.This type of structure can be processed to resist both SAGBO and general oxidation,while providing low thermal expansion and useful mechanical properties up to 700℃.Key aspects of the alloy's development are presented.
基金Supported by Project of National Natural Science Foundation(71573240)
文摘Within the framework of endogenous growth theory,the dynamic relation between age structure of population and resident consumption was studied,and explicit relation between resident consumption and dependency coefficient was obtained through Hamiltonian function method. Then,an empirical study was carried out based on panel data of 31 provinces of China in 2000-2013. The study gave following results: there is negative correlation between child dependency coefficient and resident consumption and there is positive correlation between elderly dependency coefficient and resident consumption; urbanization level weakens the negative effect of child dependency coefficient on resident consumption but it increases the positive effect of elderly dependency coefficient on resident consumption; social expenditure weakens the negative effect of child dependency coefficient on resident consumption,but it intensifies positive effect of elderly dependency coefficient on resident consumption. These results indicate that current population structure of China is favorable for growth of resident consumption demand,but in such aging population structure,economic development may lose demographic dividends.
基金supported by the Ministry of Science and Technology of China (2006BAD09A01, 200905020)the National Natural Science Fundation of China (30771661the 111 Project of China (B08049)
文摘The exceptionally large individual growth variation has been previously recognized in several sea cucumber cohorts. However, there is a lack of information regarding the mechanism of such individual differences. In this study, the sea cucumber Apostichopusjaponicus (Selenka) was reared individually in order to eliminate possible effects of social interaction, stocking density, etc. The results showed that there were substantial differences in growth among the sea cucumber individuals during the 100-day experiment. The special growth rate of the sea cucumber individuals differed by up to three folds (from 0.40% to 1.01%), and the coefficient of variation in body weight increased from 12.04% to 40.51%. The final wet body weight, food intake and food conversion efficiency for each sea cucumber were generally positively correlated with their initial wet body weight (P〈0.05). Energy budget of the animals showed that the food energy spent on respiration was much greater (about four folds) but energy deposited for growth was much less for (initially) smaller than for larger A. japonicus. The present result implies that there are obvious genetic differences among the sea cucumber individuals, largely accounting for the individual growth variation of the cohort sea cucumber. These results will provide some basic data for promoting selective breeding and fanning of the sea cucumber.
基金This work was supported by the National Natural Science Foundation of China(Grant No.10471134)grants from Specialized Research Fund for the doctoral program of Higher Education(SRFDP20050358052)Program for New Century Excellent Talents in University(NCET-05-0539).
文摘In the paper, we characterize the coefficient multiplier spaces of mixed norm spaces (Hp,q((?)1),Hu,v((?)2)) for the values of p, q, u, v in three cases: (i)0<p≤u≤∞, 0 < q≤min(1,v)≤frr. (ii) v =∞,0<p≤u≤∞, 1≤u, q≤∞. (iii) 1≤v≤2≤q≤∞, and 0<p≤u≤∞or 1≤p, u≤∞. The first case extends the result of Blasco, Jevtic, and Pavlovic in one variable. The third case generalizes partly the results of Jevtic, Jovanovic, and Wojtaszczyk to higher dimensions.
基金This work was supported by the National Natural Science Foundation of China (Grant No. 70273032).
文摘Based on the assumptions of "information transfer" and "information creation", this paper educes the multiplied growth mechanism of network information: that the gross quantity of network information (Im) is about n times as much as the quantity of real network information (Ir). According to this theoretical model, we give a uniform explanation to all kinds of information growth models in existence, and put forward some proposals, such as "forbidding information transfer" and "building up the central information base", to control the repeated information flooding on the network and facilitate the full use of network information.
基金Project supported by the National Defense Advanced Research Project,China(Grant No.315 xxxxx301)the National Defense Innovation Program,China(Grant No.48xx4)+2 种基金the National Key Technologies Research and Development Program,China(Grant No.2018YFA0306101)the Scientific Instrument Developing Project of the Chinese Academy of Sciences(Grant No.YJKYYQ20170032)the National Natural Science Foundation of China(Grant No.61505196)
文摘The InAs/AlSb heterostructures with step-graded GaAsxSb1-x metamorphic buffer layers grown on Si substrates by molecular beam epitaxy are studied. The step-graded GaAsxSb1-x metamorphic buffer layers are used to relax the strain and block defects at each interface of the layers. Meanwhile, adding Sb to GaAs is also beneficial to suppressing the formation of dislocations in the subsequent materials. The influences of the growth temperature of the step-graded GaAsxSb1-x metamorphic buffer layer on the electron mobility and surface topography are investigated for a series of samples. Based on the atomic force microscopy(AFM), high resolution x-ray diffraction(HRXRD), reciprocal space map(RSM), and Hall measurements, the crystal quality and composition of GaAsxSb1-x layer are seen to strongly depend on growth temperature while keeping the Ga growth rate and V/III ratio constant. The results show that the highest electron mobility is 10270 cm2/V·s and the roughness is 4.3 nm for the step-graded GaAsxSb1-x metamorphic buffer layer grown at a temperature of 410℃.
文摘Let g and h be two transcendental entire functions. Suppose that the Fatou set F(goh) contains multiply connected components. In this article, we will consider the growth of the functions g and h.
文摘This paper first studies the relations between the growth and the coefficients of Dirichlet series of zero order in the whole plane,and further proves that the growth of random entire functions defined by random Dirichlet series of zero order in every horizotal straight lines is almost surely equal to the growth of entire functions defined by their corresponding Dirichlet series.
基金Supported by the Key Technology Research Program of Ministry of Agriculture (No. 04-11-01B) and the National High-tech Research and Development Program of China (863 Program) (No. 2004AA603320 and 2004AA603330)
文摘Juvenile turbot (Scophthalmus maximus) the initial stock densities at 0.28, 0.87, 1.12, 1.16, 2.75 were reared in five different experiment groups in kg/m^2 respectively for the study of the density effect on growth, pigmentation and feed coefficient rate. The experiment lasted for 60 days with final stock densities at 1.91, 6.31, 8.86, 11.97, 17.67 kg/m^2 respectively. Result showed that, in the same experiment condition, the stocking density has a positive effect on growth in low density and negative in high density. The SGR (special growth rate) was 3.189, 3.304, 3.447, 3.341, and 3.087 respectively. The uniformity of weight distributing among experiment groups decreased with increasing density. The stocking density had positive effect on feed coefficient rate. Group 1 had the least feed coefficient rate 0.96, and highest at 1.25 in Group 5, the highest density group. High stocking density inhibited the growth and increased the feed coefficient rate. The stocking density had negative relationship to pigmentation improvement for whitened fish.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51361022,51561022,and 61464007)the Natural Science Foundation of Jiangxi Province,China(Grant No.20151BAB206001)
文摘Based on the Tersoff potential, molecular dynamics simulations have been performed to investigate the kinetic coefficients and growth velocities of Si(100),(110),(111), and(112) planes. The sequences of the kinetic coefficients and growth velocities are μ((100))〉 μ((110))〉 μ((112))〉 μ((111))and v((100))〉 v((110))〉 v((112))〉 v((111)), respectively, which are not consistent with the sequences of the interface energies, interplanar spacings, and melting points of the four planes. However,they agree well with the sequences of the distributions and diffusion coefficients of the melting atoms near the solid–liquid interfaces. It indicates that the atomic distributions and diffusion coefficients affected by the crystal orientations determine the anisotropic growth of silicon. The formation of stacking fault structure will further decrease the growth velocity of the Si(111) plane.