Objective To assess the data quality and estimate the provincial infant mortality rate（1q0） from China＇s sixth census. Methods A log-quadratic model is applied to under-fifteen data. We analyze and compare the aver...Objective To assess the data quality and estimate the provincial infant mortality rate（1q0） from China＇s sixth census. Methods A log-quadratic model is applied to under-fifteen data. We analyze and compare the average relative errors（AREs） for 1q0 between the estimated and reported values using the leave-one-out cross-validation method. Results For the sixth census, the AREs are more than 100% for almost all provinces. The estimated average 1q0 level for 31 provinces is 12.3‰ for males and 10.7‰ for females. Conclusion The data for the provincial 1q0 from China＇s sixth census have a serious data quality problem. The actual levels of 1q0 for each province are significantly higher than the reported values.展开更多
As a new light spot and form of current agricultural development,the sixth industry is a new way to solve the problems of rural development.This paper first introduced current situations of the development of the sixt...As a new light spot and form of current agricultural development,the sixth industry is a new way to solve the problems of rural development.This paper first introduced current situations of the development of the sixth industry in Jingzhou of Hubei Province,analyzed the related problems,and then came up with some feasible development paths.First of all,the local government should formulate the financial support policies for the sixth industry.Second,local government should focus on strengthening the cultivation of new type of agricultural business entities and carrying out agricultural brand strategy.Finally,local government should develop leisure agriculture,ecological agriculture and promote the integration of rural tourism in the whole region.展开更多
We consider the singularly perturbed sixth-order Boussinesq-type equation, which describes the bidirectional propagation of small amplitude and long capillary gravity waves on the surface of shallow water for bond num...We consider the singularly perturbed sixth-order Boussinesq-type equation, which describes the bidirectional propagation of small amplitude and long capillary gravity waves on the surface of shallow water for bond number (surface tension parameter) less than but very close to 1/3. The sufficient conditions of blow-up of solution to the Cauchy problem for this equation are given.展开更多
By using Richardson extrapolation and fourth-order compact finite difference scheme on different scale grids, a sixth-order solution is computed on the coarse grid. Other three techniques are applied to obtain a sixth...By using Richardson extrapolation and fourth-order compact finite difference scheme on different scale grids, a sixth-order solution is computed on the coarse grid. Other three techniques are applied to obtain a sixth-order solution on the fine grid, and thus give out three kinds of Richardson extrapolation-based sixth order compact computation methods. By carefully analyzing the truncation errors respectively on 2D Poisson equation, we compare the accuracy of these three sixth order methods theoretically. Numerical results for two test problems are discussed.展开更多
Hilbert’s sixth problem “The mathematical treatment of the axioms of physics” is a century-old problem that still plagues the scientific community. It is a solution necessary to establish a unified axiom of the bas...Hilbert’s sixth problem “The mathematical treatment of the axioms of physics” is a century-old problem that still plagues the scientific community. It is a solution necessary to establish a unified axiom of the basic theories of physics according to the characteristics of a mathematical axiomatic system needed to solve this problem. The cosmic continuum hypothesis can make classical theory, quantum theory and relativity have common logical foundation. According to this model, the universe is a continuum formed by the existence continuum and the existence dimension continuum. Their movement and changes can be described by an axiomatic system. The concrete steps are as follows: 1) Construct the axiom system of a cosmic continuum and establish the basic theory of force. 2) Construct the axiom system of action at a distance and establish the basic theory of field. 3) Based on the axiom system of force and field, the axiom system of the branches of physics is established.展开更多
In this work, we will derive a numerical method of sixth order in space and second order in time for solving 3-coupled nonlinear Schr<span style="white-space:nowrap;"><span style="white-space:n...In this work, we will derive a numerical method of sixth order in space and second order in time for solving 3-coupled nonlinear Schr<span style="white-space:nowrap;"><span style="white-space:nowrap;">ö</span></span>dinger equations. The numerical method is unconditionally stable. We use the exact single soliton solution and the conserved quantities to check the accuracy and the efficiency of the proposed schemes. Also, we study the interaction dynamics of two solitons. It is found that both elastic and inelastic collisions can take place under suitable parametric conditions.展开更多
基金supported by a grant from the National Science Foundation of China:A Study on the Mortality Pattern of Chinese Population and Related Statistical Models(81273179)China’s sixth census excluds the data of Hong Kong SAR,Macao SAR,and Taiwan
文摘Objective To assess the data quality and estimate the provincial infant mortality rate（1q0） from China＇s sixth census. Methods A log-quadratic model is applied to under-fifteen data. We analyze and compare the average relative errors（AREs） for 1q0 between the estimated and reported values using the leave-one-out cross-validation method. Results For the sixth census, the AREs are more than 100% for almost all provinces. The estimated average 1q0 level for 31 provinces is 12.3‰ for males and 10.7‰ for females. Conclusion The data for the provincial 1q0 from China＇s sixth census have a serious data quality problem. The actual levels of 1q0 for each province are significantly higher than the reported values.
文摘As a new light spot and form of current agricultural development,the sixth industry is a new way to solve the problems of rural development.This paper first introduced current situations of the development of the sixth industry in Jingzhou of Hubei Province,analyzed the related problems,and then came up with some feasible development paths.First of all,the local government should formulate the financial support policies for the sixth industry.Second,local government should focus on strengthening the cultivation of new type of agricultural business entities and carrying out agricultural brand strategy.Finally,local government should develop leisure agriculture,ecological agriculture and promote the integration of rural tourism in the whole region.
文摘We consider the singularly perturbed sixth-order Boussinesq-type equation, which describes the bidirectional propagation of small amplitude and long capillary gravity waves on the surface of shallow water for bond number (surface tension parameter) less than but very close to 1/3. The sufficient conditions of blow-up of solution to the Cauchy problem for this equation are given.
文摘By using Richardson extrapolation and fourth-order compact finite difference scheme on different scale grids, a sixth-order solution is computed on the coarse grid. Other three techniques are applied to obtain a sixth-order solution on the fine grid, and thus give out three kinds of Richardson extrapolation-based sixth order compact computation methods. By carefully analyzing the truncation errors respectively on 2D Poisson equation, we compare the accuracy of these three sixth order methods theoretically. Numerical results for two test problems are discussed.
文摘Hilbert’s sixth problem “The mathematical treatment of the axioms of physics” is a century-old problem that still plagues the scientific community. It is a solution necessary to establish a unified axiom of the basic theories of physics according to the characteristics of a mathematical axiomatic system needed to solve this problem. The cosmic continuum hypothesis can make classical theory, quantum theory and relativity have common logical foundation. According to this model, the universe is a continuum formed by the existence continuum and the existence dimension continuum. Their movement and changes can be described by an axiomatic system. The concrete steps are as follows: 1) Construct the axiom system of a cosmic continuum and establish the basic theory of force. 2) Construct the axiom system of action at a distance and establish the basic theory of field. 3) Based on the axiom system of force and field, the axiom system of the branches of physics is established.
文摘In this work, we will derive a numerical method of sixth order in space and second order in time for solving 3-coupled nonlinear Schr<span style="white-space:nowrap;"><span style="white-space:nowrap;">ö</span></span>dinger equations. The numerical method is unconditionally stable. We use the exact single soliton solution and the conserved quantities to check the accuracy and the efficiency of the proposed schemes. Also, we study the interaction dynamics of two solitons. It is found that both elastic and inelastic collisions can take place under suitable parametric conditions.
