The current predominant self-review mechanism by policy-making bodies suffers from deficiencies such as insufficient motivations, limited review capabilities, and weak external supervision. Third-party assessment, cha...The current predominant self-review mechanism by policy-making bodies suffers from deficiencies such as insufficient motivations, limited review capabilities, and weak external supervision. Third-party assessment, characterized by independence and specialization, is designed to mitigate these shortcomings. However, the implementation of third-party assessment faces challenges too. This paper intends to improve the third-party assessment system and to realize the legislative purpose of the system. Based on social research, discussions and exchanges with relevant parties, and the existing research results, this paper analyzes the challenges and possible optimization measures for the third-party assessment. The challenges include repulsion from policy-making bodies, insufficient independence of assessment bodies, disparity of assessment quality, and limited application of assessment outcomes. Possible optimization measures include promoting fair competition culture, increasing the acceptance of third-party assessment from policy-making bodies, enhancing the quality of third-party assessment, clarifying the relationship between policy-making bodies and assessment bodies, ensuring the independence of third-party assessments, and promoting the application of assessment results.展开更多
This paper is devoted to find the numerical solutions of one dimensional general nonlinear system of third-order boundary value problems (BVPs) for the pair of functions using Galerkin weighted residual method. We der...This paper is devoted to find the numerical solutions of one dimensional general nonlinear system of third-order boundary value problems (BVPs) for the pair of functions using Galerkin weighted residual method. We derive mathematical formulations in matrix form, in detail, by exploiting Bernstein polynomials as basis functions. A reasonable accuracy is found when the proposed method is used on few examples. At the end of the study, a comparison is made between the approximate and exact solutions, and also with the solutions of the existing methods. Our results converge monotonically to the exact solutions. In addition, we show that the derived formulations may be applicable by reducing higher order complicated BVP into a lower order system of BVPs, and the performance of the numerical solutions is satisfactory. .展开更多
The boundary value problems of the third-order ordinary differential equation have many practical application backgrounds and their some special cases have been studied by many authors. However, few scholars have stud...The boundary value problems of the third-order ordinary differential equation have many practical application backgrounds and their some special cases have been studied by many authors. However, few scholars have studied the boundary value problems of the complete third-order differential equations u′′′(t) = f (t,u(t),u′(t),u′′(t)). In this paper, we discuss the existence and uniqueness of solutions and positive solutions of the fully third-order ordinary differential equation on [0,1] with the boundary condition u(0) = u′(1) = u′′(1) = 0. Under some inequality conditions on nonlinearity f some new existence and uniqueness results of solutions and positive solutions are obtained.展开更多
The present paper proposes a mathematical method to numerically treat a class of third-order linear Boundary Value Problems (BVPs). This method is based on the combination of the Adomian Decomposition Method (ADM) and...The present paper proposes a mathematical method to numerically treat a class of third-order linear Boundary Value Problems (BVPs). This method is based on the combination of the Adomian Decomposition Method (ADM) and, the modified shooting method. A complete derivation of the proposed method has been provided, in addition to its numerical implementation and, validation via the utilization of the Runge-Kutta method and, other existing methods. The method has been applied to diverse test problems and turned out to perform remarkably. Lastly, the simulated numerical results have been graphically illustrated and, also supported by some absolute error comparison tables.展开更多
Objective:Anlotinib hydrochloride is a multitarget tyrosine kinase inhibitor that targets vascular endothelial growth factor receptor,fibroblast growth factor receptor,platelet-derived growth factor receptor,c-Kit,and...Objective:Anlotinib hydrochloride is a multitarget tyrosine kinase inhibitor that targets vascular endothelial growth factor receptor,fibroblast growth factor receptor,platelet-derived growth factor receptor,c-Kit,and c-MET;therefore,it exhibits both antitumor and anti-angiogenetic activities.A phase III trial has shown that anlotinib improved progression-free survival(PFS)and overall survival(OS)in patients with advanced non-small cell lung cancer(NSCLC),who presented with progressive disease or intolerance after standard chemotherapy.This study aimed to analyze the characteristics of patients receiving anlotinib treatment to determine the dominant populations who are fit for the treatment.Methods:Data were collected from March 2015 to January 2017 from a randomized,double-blind,placebo-controlled,multicenter,phase III trial of anlotinib(ALTER0303).A total of 437 patients were enrolled and randomly allocated(2:1)to the anlotinib and placebo groups.Kaplan–Meier analysis and log-rank test were performed to compare PFS and OS.Cox proportional hazards model was adopted for multivariate prognostic analysis.Results:Multivariate analysis indicated that high post-therapeutic peripheral blood granulocyte/lymphocyte ratio and elevated alkaline phosphatase levels were independent risk factors for PFS.Meanwhile,elevated thyroid-stimulating hormone,blood glucose,and triglyceride levels;hypertension;and hand–foot syndrome were independent protective factors of PFS.High posttherapeutic peripheral blood granulocyte/lymphocyte ratio,an Eastern Cooperative Oncology Group(ECOG)score≥2,and the sum of the maximal target lesion length at baseline were independent risk factors of OS,and hypertriglyceridemia was an independent protective factor of OS.Conclusions:This study preliminarily explored the possible factors that affected PFS and OS after anlotinib treatment in patients with advanced refractory NSCLC,and the baseline characteristics of the therapeutically dominant populations were then identified.展开更多
Stakeholders in the field of food safety management in China can be classified into three categories, government, food producers （farmers and enterprises）, and the third-party regulatory bodies. The third-party regu...Stakeholders in the field of food safety management in China can be classified into three categories, government, food producers （farmers and enterprises）, and the third-party regulatory bodies. The third-party regulation has experienced rapid development in past twenty years, and recently received considerable attention from consumers and the central government. This paper provides a review about the development, problems and future trend of the third-party regulation on food safety in China. To be specific, five forms of the third-party regulation are assessed, including media exposure, the third-party certification, regulation by consumer associations, social movements promoted by non-governmental organiza- tions （NGOs）, and regulation by industry associations. The study concludes that media and consumer associations are the major players in the third-party regulation and are highly repudiated among customers. The food certification industry has developed rapidly, but is now facing crises of confidence among consumers because of its lack of self-regulation. NGOs and industry associations still remain in the early development stages of food safety management, and therefore, are of little importance in current regulatory bodies.展开更多
This paper deals with the singular nonlinear third-order periodic boundary value problem u'' + p(3)u = f (t, u), 0 less than or equal to t less than or equal to 2pi, with u((i)) (0) = u((i)) (2pi), i = 0, 1, 2...This paper deals with the singular nonlinear third-order periodic boundary value problem u'' + p(3)u = f (t, u), 0 less than or equal to t less than or equal to 2pi, with u((i)) (0) = u((i)) (2pi), i = 0, 1, 2, where p is an element of (Graphics) and f is singular at t = 0, t = 1 and u = 0. Under suitable weaker conditions than those of [1], it is proved by constructing a special cone in C[0, 2pi] and employing the fixed point index theory that the problem has at least one or at least two positive solutions.展开更多
During the past thirty years, two generations of low alloy steels(ferrite/pearlite followed by bainite/martensite) have been developed and widely used in structural applications. The third-generation of low alloy stee...During the past thirty years, two generations of low alloy steels(ferrite/pearlite followed by bainite/martensite) have been developed and widely used in structural applications. The third-generation of low alloy steels is expected to achieve high strength and improved ductility and toughness, while satisfying the new demands for weight reduction, greenness, and safety. This paper reviews recent progress in the development of third-generation low alloy steels with an M^3 microstructure, namely, microstructures with multi-phase, meta-stable austenite, and multi-scale precipitates. The review summarizes the alloy designs and processing routes of microstructure control, and the mechanical properties of the alloys.The stabilization of retained austenite in low alloy steels is especially emphasized. Multi-scale nano-precipitates, including carbides of microalloying elements and Cu-rich precipitates obtained in third-generation low alloy steels, are then introduced. The structure–property relationships of third-generation alloys are also discussed. Finally, the promises and challenges to future applications are explored.展开更多
The definitions of the third-order elastic,piezoelectric,and dielectric constants and the properties of the associated tensors are discussed.Based on the energy conservation and coordinate transformation,the relations...The definitions of the third-order elastic,piezoelectric,and dielectric constants and the properties of the associated tensors are discussed.Based on the energy conservation and coordinate transformation,the relations among the third-order constants are obtained.Furthermore,the relations among the third-order elastic,piezoelectric,and dielectric constants of the seven crystal systems and isotropic materials are listed in detail.These third-order constants relations play an important role in solving nonlinear problems of elastic and piezoelectric materials.It is further found that all third-order piezoelectric constants are 0 for 15 kinds of point groups,while all third-order dielectric constants are 0 for 16 kinds of point groups as well as isotropic material.The reason is that some of the point groups are centrally symmetric,and the other point groups are high symmetry.These results provide the foundation to measure these constants,to choose material,and to research nonlinear problems.Moreover,these results are helpful not only for the study of nonlinear elastic and piezoelectric problems,but also for the research on flexoelectric effects and size effects.展开更多
A third-order correction was recently suggested to improve the accuracy of the half-power bandwidth method in estimating the damping of single DOF systems.This paper analyzes the accuracy of the half-power bandwidth m...A third-order correction was recently suggested to improve the accuracy of the half-power bandwidth method in estimating the damping of single DOF systems.This paper analyzes the accuracy of the half-power bandwidth method with the third-order correction in damping estimation for multi-DOF linear systems.Damping ratios in a two-DOF linear system are estimated using its displacement and acceleration frequency response curves,respectively.A wide range of important parameters that characterize the shape of these response curves are taken into account.Results show that the third-order correction may greatly improve the accuracy of the half-power bandwidth method in estimating damping in a two-DOF system.In spite of this,the half-power bandwidth method may significantly overestimate the damping ratios of two-DOF systems in some cases.展开更多
The existence of nondecreasing positive solutions for the nonlinear third-order twopoint boundary value problem u′″（t） ＋ q（t）f（t,u（t）,u′（t）） = 0, 0 〈 t 〈 1, u（0） = u″（0） = u′（1） = 0 is studied....The existence of nondecreasing positive solutions for the nonlinear third-order twopoint boundary value problem u′″（t） ＋ q（t）f（t,u（t）,u′（t）） = 0, 0 〈 t 〈 1, u（0） = u″（0） = u′（1） = 0 is studied. The iterative schemes for approximating the solutions are obtained by applying a monotone iterative method.展开更多
The status quo of Chinese agro-products logistics is analyzed from the following five aspects:the circulation mode,exchange mode,storage and transportation situation,food security.The following problems in Chinese agr...The status quo of Chinese agro-products logistics is analyzed from the following five aspects:the circulation mode,exchange mode,storage and transportation situation,food security.The following problems in Chinese agro-products logistics are pointed out,including excessive circulation sections,bad time efficiency,single payment,slow circulation,backward information processing,obvious bullwhip effect,low logistics efficiency,low logistics technology,inadequate professional equipments,low standardization degree,organized operation mode and low degree of scale.The third-party logistics mode of agro-products is analyzed and the advantages of the mode are analyzed as well.Firstly,establishing information network through integrating circulation section to accelerate the circulation of agro-products;secondly,making the operation norms by providing professional equipments to secure the quality of agricultural products;thirdly,improving the core competitiveness of the whole logistics chain by intensifying specialized work division in each section of the supply chain;fourthly,through forming scale economy to reduce logistics costs and increase the diversity of products;fifthly,through signing contracts to clarify duties and responsibilities and materialize the profit integration of the supply chain.The measures for establishing the third-party logistics of agro-products are put forward,including establish the awareness and concept of socialized logistics services;intensify the support on the third-party logistics enterprises of agro-products;lay stress on the cultivation of logistics talents of agro-products;and vigorously apply the modern marketing means.展开更多
This paper studies conformal invariance and conserved quantity of third-order Lagrange equations for non- conserved mechanical systems. Third-order Lagrange equations, the definition and a determining equation of conf...This paper studies conformal invariance and conserved quantity of third-order Lagrange equations for non- conserved mechanical systems. Third-order Lagrange equations, the definition and a determining equation of conformal invariance of the system are presented. The conformal factor expression is deduced from conformal invariance and Lie symmetry. The necessary and sufficient condition that conformal invaxiance of the system would have Lie symmetry under single-parameter infinitesimal transformations is obtained. The corresponding conserved quantity of conformal invariance is derived with the aid of a structure equation. Lastly, an example is given to illustrate the application of the results.展开更多
An existence theorem of positive solution is established for a nonlinear third-order three-point boundary value problem. Here, we concentrated on the case that the nonlinear term is neither superlinear nor sublinear, ...An existence theorem of positive solution is established for a nonlinear third-order three-point boundary value problem. Here, we concentrated on the case that the nonlinear term is neither superlinear nor sublinear, and is not asymptotic at zero and infinity.展开更多
We demonstrate spectral modulation of third-harmonic generation from molecular alignment effects. The third harmonic spectrum is broadened or narrowed under different influences of cross-phase modulations originating ...We demonstrate spectral modulation of third-harmonic generation from molecular alignment effects. The third harmonic spectrum is broadened or narrowed under different influences of cross-phase modulations originating from various molecular alignment revivals. Furthermore, the spectrum and spatial distribution of the generated third harmonic pulse change dramatically in the presence of a preformed plasma. Under the influence of a preformed plasma, a narrower third harmonic spectrum is observed, and the conical third-harmonic pulse increases while the axial part decreases. The investigation provides an effective method to modulate the spectral characteristic and spatial distribution of third-harmonic generation from intense femtosecond filament.展开更多
A novel soluble π-conjugated polymer, poly [（3-acetylpyrrole-2, 5-diyl） p-（N, N-dimethylamino） azobenzylidene] （PAPDMAABE）, was synthesized by condensation of 3-acetylpyrrole with 4-aldehyde-4＇-dimethylaminoaz...A novel soluble π-conjugated polymer, poly [（3-acetylpyrrole-2, 5-diyl） p-（N, N-dimethylamino） azobenzylidene] （PAPDMAABE）, was synthesized by condensation of 3-acetylpyrrole with 4-aldehyde-4＇-dimethylaminoazobenzene （ADMAA）. The chemical structure of PAPDMAABE was characterized by Fourier transform infrared spectroscopy （FTIR）, ^1H-NMR, and UV-Vis-NIR spectra. Transmission electron microscope （TEM） analysis for PAPDMAABE indicates that part of PAPDMAABE is in crystal state, due to the short-range order of the polymer. Thermogravimetric analysis （TGA） curve shows that the polymer has good thermal stability and its decomposition temperature is 248℃. The optical band gap of PAPDMAABE obtained from the optical absorption spectrum is about 1.73 eV. The resonant third-order nonlinear optical property of PAPDMAABE at 532 nm was studied using degenerate four-wave mixing （DFWM） technique. The resonant third-order nonlinear optical susceptibility of the polymer is about 7.48×10^-8 esu.展开更多
Based on the Stokes wave theory, the capillary-gravity wave and the interfacial internal wave in two-layer constant depth＇s fluid system are investigated. The fluids are assumed to be incompressible, inviscid and irr...Based on the Stokes wave theory, the capillary-gravity wave and the interfacial internal wave in two-layer constant depth＇s fluid system are investigated. The fluids are assumed to be incompressible, inviscid and irrotational. The third-order Stokes wave solutions are given by using a perturbation method. The results indicate that the third-order solutions depend on the surface tension, the density and the depth of each layer. As expected, the first-order solutions are the linear theoretical results （the small amplitude wave theoretical results）. The second-order and the third-order solutions describe the nonlinear modification and the nonlinear interactions. The nonlinear impact appears not only in the n （n〉~2） times＇ high frequency components, but also in the low frequency components. It is also noted that the wave velocity depends on the wave number, depth, wave amplitude and surface tension.展开更多
The introduction of third-party evaluation system and the implementation of third-party evaluation system in poverty alleviation is a major innovation in the targeted poverty alleviation work in China.In order to impr...The introduction of third-party evaluation system and the implementation of third-party evaluation system in poverty alleviation is a major innovation in the targeted poverty alleviation work in China.In order to improve the third-party evaluation mechanism,further improve the efficiency of third-party evaluation,and enhance the effectiveness of targeted poverty alleviation,this paper analyzes and summarizes the main problems existing in the current third-party evaluation practice.In view of the related problems,this paper puts forward the corresponding policy recommendations,which are believed to play a positive role in further promoting the development and improvement of the third-party evaluation of getting rid of poverty.展开更多
In this paper,we study the existence of triple positive solutions for the nonlinear third-order three-point boundary value problem ■where η∈[0,1/2) is a constant,by using a fixed-point theorem due to Avery and Pete...In this paper,we study the existence of triple positive solutions for the nonlinear third-order three-point boundary value problem ■where η∈[0,1/2) is a constant,by using a fixed-point theorem due to Avery and Peterson,we establish results of triple positive solutions to the boundary value problem,and an example is given to illustrate the importance of result obtained.展开更多
In this paper, a fully third-order accurate projection method for solving the incompressible Navier-Stokes equations is proposed. To construct the scheme, a continuous projection procedure is firstly presented. We the...In this paper, a fully third-order accurate projection method for solving the incompressible Navier-Stokes equations is proposed. To construct the scheme, a continuous projection procedure is firstly presented. We then derive a sufficient condition for the continuous projection equations to be temporally third-order accurate approximations of the original Navier-Stokes equations by means of the localtruncation-error-analysis technique. The continuous projection equations are discretized temporally and spatially to third-order accuracy on the staggered grids, resulting in a fully third-order discrete projection scheme. The possibility to design higher-order projection methods is thus demonstrated in the present paper. A heuristic stability analysis is performed on this projection method showing the probability of its being stable. The stability of the present scheme is further verified through numerical tests. The third-order accuracy of the present projection method is validated by several numerical test cases.展开更多
文摘The current predominant self-review mechanism by policy-making bodies suffers from deficiencies such as insufficient motivations, limited review capabilities, and weak external supervision. Third-party assessment, characterized by independence and specialization, is designed to mitigate these shortcomings. However, the implementation of third-party assessment faces challenges too. This paper intends to improve the third-party assessment system and to realize the legislative purpose of the system. Based on social research, discussions and exchanges with relevant parties, and the existing research results, this paper analyzes the challenges and possible optimization measures for the third-party assessment. The challenges include repulsion from policy-making bodies, insufficient independence of assessment bodies, disparity of assessment quality, and limited application of assessment outcomes. Possible optimization measures include promoting fair competition culture, increasing the acceptance of third-party assessment from policy-making bodies, enhancing the quality of third-party assessment, clarifying the relationship between policy-making bodies and assessment bodies, ensuring the independence of third-party assessments, and promoting the application of assessment results.
文摘This paper is devoted to find the numerical solutions of one dimensional general nonlinear system of third-order boundary value problems (BVPs) for the pair of functions using Galerkin weighted residual method. We derive mathematical formulations in matrix form, in detail, by exploiting Bernstein polynomials as basis functions. A reasonable accuracy is found when the proposed method is used on few examples. At the end of the study, a comparison is made between the approximate and exact solutions, and also with the solutions of the existing methods. Our results converge monotonically to the exact solutions. In addition, we show that the derived formulations may be applicable by reducing higher order complicated BVP into a lower order system of BVPs, and the performance of the numerical solutions is satisfactory. .
文摘The boundary value problems of the third-order ordinary differential equation have many practical application backgrounds and their some special cases have been studied by many authors. However, few scholars have studied the boundary value problems of the complete third-order differential equations u′′′(t) = f (t,u(t),u′(t),u′′(t)). In this paper, we discuss the existence and uniqueness of solutions and positive solutions of the fully third-order ordinary differential equation on [0,1] with the boundary condition u(0) = u′(1) = u′′(1) = 0. Under some inequality conditions on nonlinearity f some new existence and uniqueness results of solutions and positive solutions are obtained.
文摘The present paper proposes a mathematical method to numerically treat a class of third-order linear Boundary Value Problems (BVPs). This method is based on the combination of the Adomian Decomposition Method (ADM) and, the modified shooting method. A complete derivation of the proposed method has been provided, in addition to its numerical implementation and, validation via the utilization of the Runge-Kutta method and, other existing methods. The method has been applied to diverse test problems and turned out to perform remarkably. Lastly, the simulated numerical results have been graphically illustrated and, also supported by some absolute error comparison tables.
文摘Objective:Anlotinib hydrochloride is a multitarget tyrosine kinase inhibitor that targets vascular endothelial growth factor receptor,fibroblast growth factor receptor,platelet-derived growth factor receptor,c-Kit,and c-MET;therefore,it exhibits both antitumor and anti-angiogenetic activities.A phase III trial has shown that anlotinib improved progression-free survival(PFS)and overall survival(OS)in patients with advanced non-small cell lung cancer(NSCLC),who presented with progressive disease or intolerance after standard chemotherapy.This study aimed to analyze the characteristics of patients receiving anlotinib treatment to determine the dominant populations who are fit for the treatment.Methods:Data were collected from March 2015 to January 2017 from a randomized,double-blind,placebo-controlled,multicenter,phase III trial of anlotinib(ALTER0303).A total of 437 patients were enrolled and randomly allocated(2:1)to the anlotinib and placebo groups.Kaplan–Meier analysis and log-rank test were performed to compare PFS and OS.Cox proportional hazards model was adopted for multivariate prognostic analysis.Results:Multivariate analysis indicated that high post-therapeutic peripheral blood granulocyte/lymphocyte ratio and elevated alkaline phosphatase levels were independent risk factors for PFS.Meanwhile,elevated thyroid-stimulating hormone,blood glucose,and triglyceride levels;hypertension;and hand–foot syndrome were independent protective factors of PFS.High posttherapeutic peripheral blood granulocyte/lymphocyte ratio,an Eastern Cooperative Oncology Group(ECOG)score≥2,and the sum of the maximal target lesion length at baseline were independent risk factors of OS,and hypertriglyceridemia was an independent protective factor of OS.Conclusions:This study preliminarily explored the possible factors that affected PFS and OS after anlotinib treatment in patients with advanced refractory NSCLC,and the baseline characteristics of the therapeutically dominant populations were then identified.
基金the National Natural Science Foundation of China (71173225 and 71272033)
文摘Stakeholders in the field of food safety management in China can be classified into three categories, government, food producers （farmers and enterprises）, and the third-party regulatory bodies. The third-party regulation has experienced rapid development in past twenty years, and recently received considerable attention from consumers and the central government. This paper provides a review about the development, problems and future trend of the third-party regulation on food safety in China. To be specific, five forms of the third-party regulation are assessed, including media exposure, the third-party certification, regulation by consumer associations, social movements promoted by non-governmental organiza- tions （NGOs）, and regulation by industry associations. The study concludes that media and consumer associations are the major players in the third-party regulation and are highly repudiated among customers. The food certification industry has developed rapidly, but is now facing crises of confidence among consumers because of its lack of self-regulation. NGOs and industry associations still remain in the early development stages of food safety management, and therefore, are of little importance in current regulatory bodies.
文摘This paper deals with the singular nonlinear third-order periodic boundary value problem u'' + p(3)u = f (t, u), 0 less than or equal to t less than or equal to 2pi, with u((i)) (0) = u((i)) (2pi), i = 0, 1, 2, where p is an element of (Graphics) and f is singular at t = 0, t = 1 and u = 0. Under suitable weaker conditions than those of [1], it is proved by constructing a special cone in C[0, 2pi] and employing the fixed point index theory that the problem has at least one or at least two positive solutions.
基金financially supported by the National Natural Science Foundation of China (No. 51701012)the National Basic Research Program of China (973 Program: No. 2010CB630801)the Fundamental Research Funds for the Central Universities (No. FRF-TP-17-004A1)
文摘During the past thirty years, two generations of low alloy steels(ferrite/pearlite followed by bainite/martensite) have been developed and widely used in structural applications. The third-generation of low alloy steels is expected to achieve high strength and improved ductility and toughness, while satisfying the new demands for weight reduction, greenness, and safety. This paper reviews recent progress in the development of third-generation low alloy steels with an M^3 microstructure, namely, microstructures with multi-phase, meta-stable austenite, and multi-scale precipitates. The review summarizes the alloy designs and processing routes of microstructure control, and the mechanical properties of the alloys.The stabilization of retained austenite in low alloy steels is especially emphasized. Multi-scale nano-precipitates, including carbides of microalloying elements and Cu-rich precipitates obtained in third-generation low alloy steels, are then introduced. The structure–property relationships of third-generation alloys are also discussed. Finally, the promises and challenges to future applications are explored.
基金Project supported by the National Natural Science Foundation of China(Nos.11872186 and11272126)the Fundamental Research Funds for the Central Universities(No.HUST:2016JCTD114)
文摘The definitions of the third-order elastic,piezoelectric,and dielectric constants and the properties of the associated tensors are discussed.Based on the energy conservation and coordinate transformation,the relations among the third-order constants are obtained.Furthermore,the relations among the third-order elastic,piezoelectric,and dielectric constants of the seven crystal systems and isotropic materials are listed in detail.These third-order constants relations play an important role in solving nonlinear problems of elastic and piezoelectric materials.It is further found that all third-order piezoelectric constants are 0 for 15 kinds of point groups,while all third-order dielectric constants are 0 for 16 kinds of point groups as well as isotropic material.The reason is that some of the point groups are centrally symmetric,and the other point groups are high symmetry.These results provide the foundation to measure these constants,to choose material,and to research nonlinear problems.Moreover,these results are helpful not only for the study of nonlinear elastic and piezoelectric problems,but also for the research on flexoelectric effects and size effects.
基金National Natural Science Foundation under Grant No. 51179093National Basic Research Program of China under Grant No. 2011CB013602Program for New Century Excellent Talents in University under Grant No.NCET-10-0531
文摘A third-order correction was recently suggested to improve the accuracy of the half-power bandwidth method in estimating the damping of single DOF systems.This paper analyzes the accuracy of the half-power bandwidth method with the third-order correction in damping estimation for multi-DOF linear systems.Damping ratios in a two-DOF linear system are estimated using its displacement and acceleration frequency response curves,respectively.A wide range of important parameters that characterize the shape of these response curves are taken into account.Results show that the third-order correction may greatly improve the accuracy of the half-power bandwidth method in estimating damping in a two-DOF system.In spite of this,the half-power bandwidth method may significantly overestimate the damping ratios of two-DOF systems in some cases.
基金Supported by the Natural Science Foundation of Zhejiang Province (Y605144)the XNF of Zhejiang University of Media and Communications (XN080012008034)
文摘The existence of nondecreasing positive solutions for the nonlinear third-order twopoint boundary value problem u′″（t） ＋ q（t）f（t,u（t）,u′（t）） = 0, 0 〈 t 〈 1, u（0） = u″（0） = u′（1） = 0 is studied. The iterative schemes for approximating the solutions are obtained by applying a monotone iterative method.
文摘The status quo of Chinese agro-products logistics is analyzed from the following five aspects:the circulation mode,exchange mode,storage and transportation situation,food security.The following problems in Chinese agro-products logistics are pointed out,including excessive circulation sections,bad time efficiency,single payment,slow circulation,backward information processing,obvious bullwhip effect,low logistics efficiency,low logistics technology,inadequate professional equipments,low standardization degree,organized operation mode and low degree of scale.The third-party logistics mode of agro-products is analyzed and the advantages of the mode are analyzed as well.Firstly,establishing information network through integrating circulation section to accelerate the circulation of agro-products;secondly,making the operation norms by providing professional equipments to secure the quality of agricultural products;thirdly,improving the core competitiveness of the whole logistics chain by intensifying specialized work division in each section of the supply chain;fourthly,through forming scale economy to reduce logistics costs and increase the diversity of products;fifthly,through signing contracts to clarify duties and responsibilities and materialize the profit integration of the supply chain.The measures for establishing the third-party logistics of agro-products are put forward,including establish the awareness and concept of socialized logistics services;intensify the support on the third-party logistics enterprises of agro-products;lay stress on the cultivation of logistics talents of agro-products;and vigorously apply the modern marketing means.
基金Project supported by the Graduate Students Innovative Foundation of China University of Petroleum (East China) (Grant NoS2009-19)
文摘This paper studies conformal invariance and conserved quantity of third-order Lagrange equations for non- conserved mechanical systems. Third-order Lagrange equations, the definition and a determining equation of conformal invariance of the system are presented. The conformal factor expression is deduced from conformal invariance and Lie symmetry. The necessary and sufficient condition that conformal invaxiance of the system would have Lie symmetry under single-parameter infinitesimal transformations is obtained. The corresponding conserved quantity of conformal invariance is derived with the aid of a structure equation. Lastly, an example is given to illustrate the application of the results.
文摘An existence theorem of positive solution is established for a nonlinear third-order three-point boundary value problem. Here, we concentrated on the case that the nonlinear term is neither superlinear nor sublinear, and is not asymptotic at zero and infinity.
基金supported by the National Key Scientific Instrument Project,China(Grant No.2012YQ150092)the National Basic Research Program of China(Grant No.2011CB808105)+3 种基金the National Natural Science Foundation of China(Grant No.11434005)China Postdoctoral Science Foundation(Grant No.2014M560348)the National Natural Science Foundation of China(Grant No.11504237)the Shanghai Municipal Science and Technology Commission,China(Grant No.14JC1401600)
文摘We demonstrate spectral modulation of third-harmonic generation from molecular alignment effects. The third harmonic spectrum is broadened or narrowed under different influences of cross-phase modulations originating from various molecular alignment revivals. Furthermore, the spectrum and spatial distribution of the generated third harmonic pulse change dramatically in the presence of a preformed plasma. Under the influence of a preformed plasma, a narrower third harmonic spectrum is observed, and the conical third-harmonic pulse increases while the axial part decreases. The investigation provides an effective method to modulate the spectral characteristic and spatial distribution of third-harmonic generation from intense femtosecond filament.
基金the National Natural Science Foundation of China for financial support of this work(No.60277002).
文摘A novel soluble π-conjugated polymer, poly [（3-acetylpyrrole-2, 5-diyl） p-（N, N-dimethylamino） azobenzylidene] （PAPDMAABE）, was synthesized by condensation of 3-acetylpyrrole with 4-aldehyde-4＇-dimethylaminoazobenzene （ADMAA）. The chemical structure of PAPDMAABE was characterized by Fourier transform infrared spectroscopy （FTIR）, ^1H-NMR, and UV-Vis-NIR spectra. Transmission electron microscope （TEM） analysis for PAPDMAABE indicates that part of PAPDMAABE is in crystal state, due to the short-range order of the polymer. Thermogravimetric analysis （TGA） curve shows that the polymer has good thermal stability and its decomposition temperature is 248℃. The optical band gap of PAPDMAABE obtained from the optical absorption spectrum is about 1.73 eV. The resonant third-order nonlinear optical property of PAPDMAABE at 532 nm was studied using degenerate four-wave mixing （DFWM） technique. The resonant third-order nonlinear optical susceptibility of the polymer is about 7.48×10^-8 esu.
基金financially supported by the Science Research Project of Inner Mongolia University of Technology,China(Grant No.ZD201613)
文摘Based on the Stokes wave theory, the capillary-gravity wave and the interfacial internal wave in two-layer constant depth＇s fluid system are investigated. The fluids are assumed to be incompressible, inviscid and irrotational. The third-order Stokes wave solutions are given by using a perturbation method. The results indicate that the third-order solutions depend on the surface tension, the density and the depth of each layer. As expected, the first-order solutions are the linear theoretical results （the small amplitude wave theoretical results）. The second-order and the third-order solutions describe the nonlinear modification and the nonlinear interactions. The nonlinear impact appears not only in the n （n〉~2） times＇ high frequency components, but also in the low frequency components. It is also noted that the wave velocity depends on the wave number, depth, wave amplitude and surface tension.
基金Supported by the Construction Project of Party Branch Secretary’s Studio of "Double Leader" Teachers in Colleges and Universities of the Ministry of Education of ChinaThe Project of Party Construction Research of Yunnan University of Finance and Economics
文摘The introduction of third-party evaluation system and the implementation of third-party evaluation system in poverty alleviation is a major innovation in the targeted poverty alleviation work in China.In order to improve the third-party evaluation mechanism,further improve the efficiency of third-party evaluation,and enhance the effectiveness of targeted poverty alleviation,this paper analyzes and summarizes the main problems existing in the current third-party evaluation practice.In view of the related problems,this paper puts forward the corresponding policy recommendations,which are believed to play a positive role in further promoting the development and improvement of the third-party evaluation of getting rid of poverty.
基金The National Natural Science Foundation of China(11661071)
文摘In this paper,we study the existence of triple positive solutions for the nonlinear third-order three-point boundary value problem ■where η∈[0,1/2) is a constant,by using a fixed-point theorem due to Avery and Peterson,we establish results of triple positive solutions to the boundary value problem,and an example is given to illustrate the importance of result obtained.
基金The project supported by the China NKBRSF(2001CB409604)
文摘In this paper, a fully third-order accurate projection method for solving the incompressible Navier-Stokes equations is proposed. To construct the scheme, a continuous projection procedure is firstly presented. We then derive a sufficient condition for the continuous projection equations to be temporally third-order accurate approximations of the original Navier-Stokes equations by means of the localtruncation-error-analysis technique. The continuous projection equations are discretized temporally and spatially to third-order accuracy on the staggered grids, resulting in a fully third-order discrete projection scheme. The possibility to design higher-order projection methods is thus demonstrated in the present paper. A heuristic stability analysis is performed on this projection method showing the probability of its being stable. The stability of the present scheme is further verified through numerical tests. The third-order accuracy of the present projection method is validated by several numerical test cases.
