The incorporation of human rights clauses into the constitution has propelled the innovation of fundamental rights hermeneutics in terms of the subjects of the legal relationships of fundamental rights,the nature of f...The incorporation of human rights clauses into the constitution has propelled the innovation of fundamental rights hermeneutics in terms of the subjects of the legal relationships of fundamental rights,the nature of fundamental rights,the forms of state obligations,the scope of fundamental rights,among other aspects.Regarding the subjects of the legal relationships of fundamental rights,human rights clauses have expanded the subjects of fundamental rights from citizens to natural persons.They have also narrowed down the duty-bearing subjects directed by fundamental rights in clauses that do not define duty-bearing subjects from all entities to state public power.Additionally,in fundamental rights clauses that stipulate private entities as duty-bearing subjects,the duty-bearing subjects have been narrowed down from all private entities to social public power entities.In terms of the nature of fundamental rights,human rights clauses have endowed each specific basic right with dual characteristics of the right to respect and the right to protection.Regarding the forms of state obligations,human rights clauses have established the state obligations corresponding to each specific basic right as obligations to respect and to protect.In terms of the scope of fundamental rights,human rights clauses do not have the function of independently justifying unenumerated fundamental rights,but they can assist other clauses in justifying unenumerated fundamental rights,thereby expanding the scope of fundamental rights to a limited extent.展开更多
A major bottleneck in large-scale eigenfrequency topology optimization is the repeated solution of the generalized eigenvalue problem.This work presents an efficient graphics processing unit(GPU)solver for threedimens...A major bottleneck in large-scale eigenfrequency topology optimization is the repeated solution of the generalized eigenvalue problem.This work presents an efficient graphics processing unit(GPU)solver for threedimensional(3D)topology optimization that maximizes the fundamental eigenfrequency.The Successive Iteration of Analysis and Design(SIAD)framework is employed to avoid solving a full eigenproblem at every iteration.The sequential approximation of the eigenpairs is solved by the GPU-accelerated multigrid-preconditioned conjugate gradient(MGPCG)method to efficiently improve the eigenvectors along with the topological evolution.The cluster-mean approach is adopted to address the non-differentiability issue caused by repeated eigenfrequencies.The corresponding sensitivity analysis method is provided.The parallelized gradient-based Zhang-Paulino-Ramos Jr.(ZPR)algorithm is employed to update the design variables.The effectiveness of the proposed solver is demonstrated through two large-scale numerical examples.The first example demonstrates the accuracy,efficiency,and scalability of the proposed solver by solving a 3D optimization problem of 50.33 million elements being solved in approximately 15.2 h over 300 iterations on a single NVIDIA Tesla V100 GPU.The second example validates the effectiveness of the proposed solver in the presence of repeated eigenfrequencies.Our findings also highlight that higher-resolution models produce distinct optimized structures with higher fundamental frequencies,underscoring the necessity of large-scale topology optimization.展开更多
This article focuses on the teaching of circuit foundation courses in vocational colleges and explores in depth the application of MWorks simulation software.By analyzing the limitations of traditional circuit foundat...This article focuses on the teaching of circuit foundation courses in vocational colleges and explores in depth the application of MWorks simulation software.By analyzing the limitations of traditional circuit foundation course teaching,this article elaborates on the advantages of MWorks software in teaching,including intuitive presentation of circuit principles,provision of rich component libraries,and powerful analysis functions.Detailed teaching practice cases based on the software were introduced,such as simple circuit construction and analysis,complex circuit fault troubleshooting,etc.,and the application effect was demonstrated by comparing actual teaching data.The results show that MWorks simulation software effectively enhances students’learning interest,practical ability,and theoretical knowledge mastery,providing strong support for the improvement of the teaching quality of circuit foundation courses in vocational colleges.展开更多
In 2024,China’s human rights research has assumed a distinct“autonomy-oriented shift,”with scholars beginning to refine and construct uniquely Chinese and locally identifiable human rights concepts,categories,and d...In 2024,China’s human rights research has assumed a distinct“autonomy-oriented shift,”with scholars beginning to refine and construct uniquely Chinese and locally identifiable human rights concepts,categories,and discourses.Building an independent human rights knowledge system has become a core academic focus in China’s human rights research field.Upholding fundamental principles and breaking new ground are the key methodological principles for the process.China’s human rights research should be rooted in the“cultural lineage”by preserving the essence of fine traditional Chinese culture,guided by the“moral lineage”by adhering to the Marxist view on human rights,and anchored in the“Four-sphere Confidence”by upholding a distinct human rights development path,so as to define the historical coordinates and value stance of China’s independent human rights knowledge system.Meanwhile,it should maintain a high degree of openness in knowledge,theory,and methodology to address emerging rights demands and contribute to building a new global human rights governance order,so as to underscore the mission of China’s independent human rights knowledge system in the contemporary era and China’s responsibility as a major global actor.China’s human rights research should uphold the dialectical unity between the fundamental principles and innovations,and advance the systemic and theoretical interpretation of its independent human rights knowledge.展开更多
The macroscopic fundamental diagram（ MFD） is studied to obtain the aggregate behavior of traffic in cities. This paper investigates the existence and the characteristics of different types of daily MFD for the Shang...The macroscopic fundamental diagram（ MFD） is studied to obtain the aggregate behavior of traffic in cities. This paper investigates the existence and the characteristics of different types of daily MFD for the Shanghai urban expressway network. The existence of MFD in the Shanghai urban expressway network is proved based on two weeks＇ data.Moreover, the hysteresis phenomena is present in most days and the network exhibits different hysteresis loops under different traffic situations. The relationship between the hysteresis phenomena and the inhomogeneity of traffic distribution is verified. The MFDs in the years of 2009 and 2012 are compared. The hysteresis loop still exists in 2012, which further verifies the existence of the hysteresis phenomenon. The direct relationship between the length of the hysteresis loop（ ΔO） and the congestion is proved based on sufficient data. The width of the hysteresis loop, i. e., the drop in network flow（ ΔQ） has no relationship with the congestion, and it varies from day to day under different traffic situations.展开更多
This paper gives several fundamental theorems for the stability, uniform stability, asymptotic stability and uniform asymptotic stability. Those theorems allow the derivative of Lyapunov functions to be positive on ce...This paper gives several fundamental theorems for the stability, uniform stability, asymptotic stability and uniform asymptotic stability. Those theorems allow the derivative of Lyapunov functions to be positive on certain sets,relax the restriction about the rate of change of state variable in a system to be bounded in Marachkov's theorem and extend the related results in [4—7].展开更多
In order to improve the performance of estimating the fundamental matrix, a key problem arising in stereo vision, a novel method based on stripe constraints is presented. In contrast to traditional methods based on al...In order to improve the performance of estimating the fundamental matrix, a key problem arising in stereo vision, a novel method based on stripe constraints is presented. In contrast to traditional methods based on algebraic least-square algorithms, the proposed approach aims to minimize a cost function that is derived from the minimum radius of the Hough transform. In a structured-light system with a particular stripe code pattern, there are linear constraints that the points with the same code are on the same surface. Using the Hough transform, the pixels with the same code map to the Hough space, and the radius of the intersections can be defined as the evaluation function in the optimization progress. The global optimum solution of the fundamental matrix can be estimated using a Levenberg- Marquardt optimization iterative process based on the Hough transform radius. Results illustrate the validity of this algorithm, and prove that this method can obtain good performance with high efficiency.展开更多
Raman spectra of purified oxygen evolution core complexes (Pd OECC) thin films on silver mirror substrates have been taken over the frequency range of 250-3100 cm -1 by surface enhanced Raman scattering (SERS). B...Raman spectra of purified oxygen evolution core complexes (Pd OECC) thin films on silver mirror substrates have been taken over the frequency range of 250-3100 cm -1 by surface enhanced Raman scattering (SERS). Besides the fundamental frequency modes of β_carotene in Pd OECC, many weak peaks are observed. According to the selection rules of overtone and combination bands, most of them are attributed to the second_order Raman spectra of β_carotene. Compared with the SERS of normal Pd OECC, the SERS of Pd OECC after strong illumination shows a decrease in scattering intensity and an increase in line widths, indicating changes of conformation and micro_environment of β_carotene. The results of SERS are consistent with the changes of absorption spectrum of Pd OECC induced by strong illumination. There are no changes that can be ascribed to new vibration bands, so it is deduced that Pd OECC on the silver mirror is identical to that in the solution. In summary, SERS proved a good method to study the photodamage mechanism of photosynthesis.展开更多
We call a group A-simple,if it has no non-trivial normal abelian subgroup.We will present finiteness results in controlled topology via geometry on manifolds whose fundamental groups are A-simple.
Every four years the Committee on Data for Science and Technology (CODATA) supplies a self-consistent set of values of the basic constants and conversion factors of physics recommended for international use. In 2013, ...Every four years the Committee on Data for Science and Technology (CODATA) supplies a self-consistent set of values of the basic constants and conversion factors of physics recommended for international use. In 2013, the World-Universe Model (WUM) proposed a principally different depiction of the World as an alternative to the picture of the Big Bang Model. This article: 1) Gives the short history of Classical Physics before Special Relativity;2) Calculates Fundamental Physical Constants based on experimentally measured Rydberg constant, Electrodynamic constant, Electron Charge-to-Mass Ratio, and Planck constant;3) Discusses Electrodynamic constant and Speed of Light;4) Considers Dimensionless Fundamental Parameters (Dirac Large Number Q and Dimensionless Rydberg Constant α);5) Calculates Newtonian Constant of Gravitation based on the Inter-connectivity of Primary Physical Parameters;6) Makes a detailed analysis of the Self-consistency of Fundamental Physical Constants and Primary Physical Parameters through the prism of WUM. The performed analysis suggests: 1) Discontinuing using the notion “Vacuum” and its characteristics (Speed of Light in Vacuum, Characteristic Impedance of Vacuum, Vacuum Magnetic Permeability, Vacuum Electric Permittivity);2) Accepting the exact numerical values of Electrodynamic constant, Planck constant, Elementary charge, and Dimensionless Rydberg Constant α. WUM recommends the predicted value of Newtonian Constant of Gravitation in 2018 to be considered in CODATA Recommend Values of the Fundamental Physical Constants 2022.展开更多
Purpose: To examine the associations among preschoolers fundamental motor skills, screen-time, physical activity(PA), and sedentary behavior(SB).Methods: Children ages 3à4 years were enrolled in a prospective obs...Purpose: To examine the associations among preschoolers fundamental motor skills, screen-time, physical activity(PA), and sedentary behavior(SB).Methods: Children ages 3à4 years were enrolled in a prospective observational trial of PA. Trained assessors conducted the Test of Gross Motor Development-3 rd edition(TGMD-3), and the Movement Assessment Battery for Children-2 nd edition, and parent-reported child screen-time and sociodemographic information. Children wore an accelerometer for 7 days to examine SB and total PA(TPA). TPA was further characterized as moderateto-vigorous PA(MVPA) or vigorous PA(VPA). Mixed linear models were calculated, controlling for age(for TGMD-3), sex, household income, and accelerometer wear time(for accelerometry models), with childcare center as a random effect. The primary analysis reported on the cross-sectional baseline data of 126 children with complete fundamental motor skill and screen-time data; a subanalysis included 88 children with complete accelerometry data.Results: Children were 3.4 § 0.5 years of age(54% girls; 46% white, 42% African American, 12% other). A total of 48% lived in households at or below the federal poverty level. Children engaged in 5.1 § 3.6 h/day of screen-time. Children's screen-time was inversely related to the Movement Assessment Battery for Children-2 nd edition, manual dexterity skills percentile(b(SE) = ?1.7(0.8), p = 0.049). In the accelerometry subsample,children engaged in 5.9 § 0.9 h/day of TPA of which 1.7 § 0.6 h/day was MVPA. Boys engaged in more MVPA and VPA and less SB compared with girls(all p < 0.05). A higher TGMD-3, total score(b(SE) = 0.4(0.2), p = 0.017) and locomotor score(b(SE) = 0.7(0.3), p = 0.018) were associated with more VPA but not with TPA or MVPA. Screen-time and television in the bedroom were not related to SB, TPA, MVPA, or VPA.Conclusion: Children's motor skills were positively related to VPA but inversely related to screen-time. Further inquiry into the implications of high exposure to screen-time in young children is needed.展开更多
In a wind-vehicle-bridge(WVB) system,there are various interactions among wind,vehicle and bridge.The mechanism for coupling vibration of wind-vehicle-bridge systems is explored to demonstrate the effects of fundament...In a wind-vehicle-bridge(WVB) system,there are various interactions among wind,vehicle and bridge.The mechanism for coupling vibration of wind-vehicle-bridge systems is explored to demonstrate the effects of fundamental factors,such as mean wind,fluctuating wind,buffeting,rail irregularities,light rail vehicle vibration and bridge stiffness.A long cable-stayed bridge which carries light rail traffic is regarded as a numerical example.Firstly,a finite element model is built for the long cable-stayed bridge.The deck can generally be idealized as three-dimensional spine beam while cables are modeled as truss elements.Vehicles are modeled as mass-spring-damper systems.Rail irregularities and wind fluctuation are simulated in time domain by spectrum representation method.Then,aerodynamic loads on vehicle and bridge deck are measured by section model wind tunnel tests.Eight vertical and torsional flutter derivatives of bridge deck are identified by weighting ensemble least-square method.Finally,dynamic responses of the WVB system are analyzed in a series of cases.The results show that the accelerations of the vehicle are excited by the fluctuating wind and the track irregularity to a great extent.The transverse forces of wheel axles mainly depend on the track irregularity.The displacements of the bridge are predominantly determined by the mean wind and restricted by its stiffness.And the accelerations of the bridge are enlarged after adding the fluctuating wind.展开更多
A new type of hybrid finite element formulation with fundamental solutions as internal interpolation functions, named as HFS-FEM, is presented in this paper and used for solving two dimensional heat conduction problem...A new type of hybrid finite element formulation with fundamental solutions as internal interpolation functions, named as HFS-FEM, is presented in this paper and used for solving two dimensional heat conduction problems in single and multi-layer materials. In the proposed approach, a new variational functional is firstly constructed for the proposed HFS-FE model and the related existence of extremum is presented. Then, the assumed internal potential field constructed by the linear combination of fundamental solutions at points outside the elemental domain under consideration is used as the internal interpolation function, which analytically satisfies the governing equation within each element. As a result, the domain integrals in the variational functional formulation can be converted into the boundary integrals which can significantly simplify the calculation of the element stiffness matrix. The independent frame field is also introduced to guarantee the inter-element continuity and the stationary condition of the new variational functional is used to obtain the final stiffness equations. The proposed method inherits the advantages of the hybrid Trefftz finite element method （HT-FEM） over the conventional finite element method （FEM） and boundary element method （BEM）, and avoids the difficulty in selecting appropriate terms of T-complete functions used in HT-FEM, as the fundamental solutions contain usually one term only, rather than a series containing infinitely many terms. Further, the fundamental solutions of a problem are, in general, easier to derive than the T-complete functions of that problem. Finally, several examples are presented to assess the performance of the proposed method, and the obtained numerical results show good numerical accuracy and remarkable insensitivity to mesh distortion.展开更多
The present work describes the application of the method of fundamental solutions （MFS） along with the analog equation method （AEM） and radial basis function （RBF） approximation for solving the 2D isotropic and ...The present work describes the application of the method of fundamental solutions （MFS） along with the analog equation method （AEM） and radial basis function （RBF） approximation for solving the 2D isotropic and anisotropic Helmholtz problems with different wave numbers. The AEM is used to convert the original governing equation into the classical Poisson＇s equation, and the MFS and RBF approximations are used to derive the homogeneous and particular solutions, respectively. Finally, the satisfaction of the solution consisting of the homogeneous and particular parts to the related governing equation and boundary conditions can produce a system of linear equations, which can be solved with the singular value decomposition （SVD） technique. In the computation, such crucial factors related to the MFS-RBF as the location of the virtual boundary, the differential and integrating strategies, and the variation of shape parameters in multi-quadric （MQ） are fully analyzed to provide useful reference.展开更多
Purpose: To identify the social-ecological correlates associated with fundamental movement skills at the child, family, and environment levels in young children.Methods: Preschool children from 4 Colorado Head Start/p...Purpose: To identify the social-ecological correlates associated with fundamental movement skills at the child, family, and environment levels in young children.Methods: Preschool children from 4 Colorado Head Start/preschool centers were recruited from 2010 to 2012. Two hundred twenty-eight children(128 girls; age = 56.08 § 4.09 months; body mass index(BMI) z-score = 0.53 § 1.12(mean § SD); 42.1% Hispanic/Latino) and 159 families were included in the final analysis. Children's perceived competence and fundamental movement skills were assessed via the Pictorial Scale of Perceived Competence and Social Acceptance and the Bruininks-Oseretsky Test of Motor Proficiency, 2 nd edition. Data on the number of children in the family, parent age, BMI, education, employment status, family income, perception of child coordination, and home physical activity environment were collected via a questionnaire. Linear regressions adjusted for child BMI, age, sex, and school site were performed at each level.Results: Child perceived cognitive competence was positively associated with locomotor skills(p = 0.04; adjusted R2= 0.035) and object-control skills(p = 0.003; adjusted R2= 0.083) at the child level. Parent education, BMI, and perception of child coordination were positively associated with locomotor skills and explained 8.8% of variance, but only parent education was significant(p = 0.04) at the family level. In addition, physical environment was positively associated with locomotor skills(p = 0.02) and explained 5.5% of variance at the environment level.Conclusion: Social-ecological correlates associated with young children's fundamental movement skills are multidimensional and differ according to skill category at the child, family, and environment levels.展开更多
In this paper, adaptive genetic algorithm （AGA） is applied to topology optimization of truss structure with frequency domain excitations. The optimization constraints include fundamental frequency, displacement resp...In this paper, adaptive genetic algorithm （AGA） is applied to topology optimization of truss structure with frequency domain excitations. The optimization constraints include fundamental frequency, displacement responses under force excitations and acceleration responses under foundation acceleration excitations. The roulette wheel selection operator, adaptive crossover and mutation operators are used as genetic operators. Some heuristic strategies are put forward to direct the deletion of the extra bars and nodes on truss structures. Three examples demonstrate that the proposed method can yield the optimum structure form and the lightest weight of the given ground structure while satisfying dynamic response constraints.展开更多
Background:Physical activity(PA)in the early years is associated with a range of positive health outcomes.Fundamental motor skill(FMS)competence is associated with PA and is theorized to be driven by PA in the early y...Background:Physical activity(PA)in the early years is associated with a range of positive health outcomes.Fundamental motor skill(FMS)competence is associated with PA and is theorized to be driven by PA in the early years and vice versa in mid to late childhood.However,to date,no studies have meta-analyzed the association between PA and FMS in the early years.Methods:Six electronic databases were searched for articles published up to April 2019.Cross-sectional and longitudinal studies were included if they targeted children(ages 3-6 year)as the population of the study and assessed the association between objectively measured PA and FMS.Total FMS,total physical activity(TPA),and moderate-to-vigorous physical activity(MVPA)data were meta-analyzed using a random effects model.Results:We identified 24,815 titles and abstracts.In total,19 studies met the inclusion criteria,including 14 cross-sectional and 4 longitudinal studies,as well as 1 study with cross-sectional and longitudinal analysis.There was a significant but small positive association between FMS and MVPA(r=0.20,95%confidence interval(CI):0.13-0.26)and TPA(r=0.20,95%CI:0.12-0.28).Findings from longitudinal studies revealed that PA drives FMS in early childhood.Mediation was explored in 1 study,which found that perceived motor competence did not mediate the association between FMS and PA.Conclusion:Using a meta-analysis,this study is the first to show a positive association between FMS,MVPA,and TPA in the early years of childhood,suggesting that the association begins at an early age.Limited evidence from longitudinal studies supports the theory that PA drives FMS in the early years of childhood.More evidence is needed from large studies to track PA and FMS until mid to late childhood and to explore the mediators of this association.展开更多
The highly conductive solid-state electrolytes (SSEs) have led to great progress in the development of all-solid-state batteries (ASSBs);however, there are obstacles to their application such as poor interfacial stabi...The highly conductive solid-state electrolytes (SSEs) have led to great progress in the development of all-solid-state batteries (ASSBs);however, there are obstacles to their application such as poor interfacial stability, scalability challenges, production safety and sustainability of ASSBs which still demand prompt solution. In Nature Nanotechnology, Tan and colleagues summarize solutions to overcome some major fundamental obstacles faced by the ASSB community。展开更多
Flotation is a complex process that occurs in solid-liquid-gas multiphase systems,and its main factors include the minerals,separation medium,as well as various flotation reagents.The study of mineral properties and i...Flotation is a complex process that occurs in solid-liquid-gas multiphase systems,and its main factors include the minerals,separation medium,as well as various flotation reagents.The study of mineral properties and interactions with other components such as reagents and water lays the basic theoretical foundation for flotation.Density functional theory(DFT) calculations can qualitatively evaluate the exchange of matter and energy between the mineral system and the surroundings and quantitatively characterize these behaviors,which greatly expands the breadth and depth of flotation studies.This review systematically summarizes the advances of flotation research based on DFT studies,including the study of mineral crystal chemistry represented by the theory of lattice defects,mineral surface hydration such as hydrophilicity and hydrophobicity,surface regulation mechanism,and collecting mechanism based on surface adsorption theory.More significantly,it systematically elaborates different types of collectors according to their characteristics and emphatically explains the mechanism of some typical collectors in detail.展开更多
基金the Ministry of Education’s Major Special Project for Philosophical and Social Science Research,“A Study on the Conceptual System of China’s Independent Legal Knowledge System”(Project Number 2023JZDZ014)the Ministry of Education’s Humanities and Social Science Research Planning Fund Project,“A Study on the Improvement of the Villager Self-Governance System in the Context of Land Circulation”(Project Number 19YJA820027).
文摘The incorporation of human rights clauses into the constitution has propelled the innovation of fundamental rights hermeneutics in terms of the subjects of the legal relationships of fundamental rights,the nature of fundamental rights,the forms of state obligations,the scope of fundamental rights,among other aspects.Regarding the subjects of the legal relationships of fundamental rights,human rights clauses have expanded the subjects of fundamental rights from citizens to natural persons.They have also narrowed down the duty-bearing subjects directed by fundamental rights in clauses that do not define duty-bearing subjects from all entities to state public power.Additionally,in fundamental rights clauses that stipulate private entities as duty-bearing subjects,the duty-bearing subjects have been narrowed down from all private entities to social public power entities.In terms of the nature of fundamental rights,human rights clauses have endowed each specific basic right with dual characteristics of the right to respect and the right to protection.Regarding the forms of state obligations,human rights clauses have established the state obligations corresponding to each specific basic right as obligations to respect and to protect.In terms of the scope of fundamental rights,human rights clauses do not have the function of independently justifying unenumerated fundamental rights,but they can assist other clauses in justifying unenumerated fundamental rights,thereby expanding the scope of fundamental rights to a limited extent.
基金support from the National Natural Science Foundation of China(Award No.52105240).
文摘A major bottleneck in large-scale eigenfrequency topology optimization is the repeated solution of the generalized eigenvalue problem.This work presents an efficient graphics processing unit(GPU)solver for threedimensional(3D)topology optimization that maximizes the fundamental eigenfrequency.The Successive Iteration of Analysis and Design(SIAD)framework is employed to avoid solving a full eigenproblem at every iteration.The sequential approximation of the eigenpairs is solved by the GPU-accelerated multigrid-preconditioned conjugate gradient(MGPCG)method to efficiently improve the eigenvectors along with the topological evolution.The cluster-mean approach is adopted to address the non-differentiability issue caused by repeated eigenfrequencies.The corresponding sensitivity analysis method is provided.The parallelized gradient-based Zhang-Paulino-Ramos Jr.(ZPR)algorithm is employed to update the design variables.The effectiveness of the proposed solver is demonstrated through two large-scale numerical examples.The first example demonstrates the accuracy,efficiency,and scalability of the proposed solver by solving a 3D optimization problem of 50.33 million elements being solved in approximately 15.2 h over 300 iterations on a single NVIDIA Tesla V100 GPU.The second example validates the effectiveness of the proposed solver in the presence of repeated eigenfrequencies.Our findings also highlight that higher-resolution models produce distinct optimized structures with higher fundamental frequencies,underscoring the necessity of large-scale topology optimization.
基金MWorks University Application Verification Project(BX2024C081)。
文摘This article focuses on the teaching of circuit foundation courses in vocational colleges and explores in depth the application of MWorks simulation software.By analyzing the limitations of traditional circuit foundation course teaching,this article elaborates on the advantages of MWorks software in teaching,including intuitive presentation of circuit principles,provision of rich component libraries,and powerful analysis functions.Detailed teaching practice cases based on the software were introduced,such as simple circuit construction and analysis,complex circuit fault troubleshooting,etc.,and the application effect was demonstrated by comparing actual teaching data.The results show that MWorks simulation software effectively enhances students’learning interest,practical ability,and theoretical knowledge mastery,providing strong support for the improvement of the teaching quality of circuit foundation courses in vocational colleges.
基金a phased result funded by the Special Funds for Basic Scientific Research Expenses of Universities under the Central Government(24CXTD01).
文摘In 2024,China’s human rights research has assumed a distinct“autonomy-oriented shift,”with scholars beginning to refine and construct uniquely Chinese and locally identifiable human rights concepts,categories,and discourses.Building an independent human rights knowledge system has become a core academic focus in China’s human rights research field.Upholding fundamental principles and breaking new ground are the key methodological principles for the process.China’s human rights research should be rooted in the“cultural lineage”by preserving the essence of fine traditional Chinese culture,guided by the“moral lineage”by adhering to the Marxist view on human rights,and anchored in the“Four-sphere Confidence”by upholding a distinct human rights development path,so as to define the historical coordinates and value stance of China’s independent human rights knowledge system.Meanwhile,it should maintain a high degree of openness in knowledge,theory,and methodology to address emerging rights demands and contribute to building a new global human rights governance order,so as to underscore the mission of China’s independent human rights knowledge system in the contemporary era and China’s responsibility as a major global actor.China’s human rights research should uphold the dialectical unity between the fundamental principles and innovations,and advance the systemic and theoretical interpretation of its independent human rights knowledge.
基金The National Natural Science Foundation of China(No.51238008)
文摘The macroscopic fundamental diagram（ MFD） is studied to obtain the aggregate behavior of traffic in cities. This paper investigates the existence and the characteristics of different types of daily MFD for the Shanghai urban expressway network. The existence of MFD in the Shanghai urban expressway network is proved based on two weeks＇ data.Moreover, the hysteresis phenomena is present in most days and the network exhibits different hysteresis loops under different traffic situations. The relationship between the hysteresis phenomena and the inhomogeneity of traffic distribution is verified. The MFDs in the years of 2009 and 2012 are compared. The hysteresis loop still exists in 2012, which further verifies the existence of the hysteresis phenomenon. The direct relationship between the length of the hysteresis loop（ ΔO） and the congestion is proved based on sufficient data. The width of the hysteresis loop, i. e., the drop in network flow（ ΔQ） has no relationship with the congestion, and it varies from day to day under different traffic situations.
文摘This paper gives several fundamental theorems for the stability, uniform stability, asymptotic stability and uniform asymptotic stability. Those theorems allow the derivative of Lyapunov functions to be positive on certain sets,relax the restriction about the rate of change of state variable in a system to be bounded in Marachkov's theorem and extend the related results in [4—7].
文摘In order to improve the performance of estimating the fundamental matrix, a key problem arising in stereo vision, a novel method based on stripe constraints is presented. In contrast to traditional methods based on algebraic least-square algorithms, the proposed approach aims to minimize a cost function that is derived from the minimum radius of the Hough transform. In a structured-light system with a particular stripe code pattern, there are linear constraints that the points with the same code are on the same surface. Using the Hough transform, the pixels with the same code map to the Hough space, and the radius of the intersections can be defined as the evaluation function in the optimization progress. The global optimum solution of the fundamental matrix can be estimated using a Levenberg- Marquardt optimization iterative process based on the Hough transform radius. Results illustrate the validity of this algorithm, and prove that this method can obtain good performance with high efficiency.
基金The State Key Basic Research and Developmental Plan(G1998010100).
文摘Raman spectra of purified oxygen evolution core complexes (Pd OECC) thin films on silver mirror substrates have been taken over the frequency range of 250-3100 cm -1 by surface enhanced Raman scattering (SERS). Besides the fundamental frequency modes of β_carotene in Pd OECC, many weak peaks are observed. According to the selection rules of overtone and combination bands, most of them are attributed to the second_order Raman spectra of β_carotene. Compared with the SERS of normal Pd OECC, the SERS of Pd OECC after strong illumination shows a decrease in scattering intensity and an increase in line widths, indicating changes of conformation and micro_environment of β_carotene. The results of SERS are consistent with the changes of absorption spectrum of Pd OECC induced by strong illumination. There are no changes that can be ascribed to new vibration bands, so it is deduced that Pd OECC on the silver mirror is identical to that in the solution. In summary, SERS proved a good method to study the photodamage mechanism of photosynthesis.
基金the author Rong at Capital Normal University,which was partially supported by NSFC Grant 11821101,Beijing Natural Science Foundation Z19003,and a research fund from Capital Normal University.
文摘We call a group A-simple,if it has no non-trivial normal abelian subgroup.We will present finiteness results in controlled topology via geometry on manifolds whose fundamental groups are A-simple.
文摘Every four years the Committee on Data for Science and Technology (CODATA) supplies a self-consistent set of values of the basic constants and conversion factors of physics recommended for international use. In 2013, the World-Universe Model (WUM) proposed a principally different depiction of the World as an alternative to the picture of the Big Bang Model. This article: 1) Gives the short history of Classical Physics before Special Relativity;2) Calculates Fundamental Physical Constants based on experimentally measured Rydberg constant, Electrodynamic constant, Electron Charge-to-Mass Ratio, and Planck constant;3) Discusses Electrodynamic constant and Speed of Light;4) Considers Dimensionless Fundamental Parameters (Dirac Large Number Q and Dimensionless Rydberg Constant α);5) Calculates Newtonian Constant of Gravitation based on the Inter-connectivity of Primary Physical Parameters;6) Makes a detailed analysis of the Self-consistency of Fundamental Physical Constants and Primary Physical Parameters through the prism of WUM. The performed analysis suggests: 1) Discontinuing using the notion “Vacuum” and its characteristics (Speed of Light in Vacuum, Characteristic Impedance of Vacuum, Vacuum Magnetic Permeability, Vacuum Electric Permittivity);2) Accepting the exact numerical values of Electrodynamic constant, Planck constant, Elementary charge, and Dimensionless Rydberg Constant α. WUM recommends the predicted value of Newtonian Constant of Gravitation in 2018 to be considered in CODATA Recommend Values of the Fundamental Physical Constants 2022.
基金supported by the Gulf States Collaborative Center for Health Policy Research (Gulf States-HPC) from the National Institute on Minority Health and Health Disparities of the National Institutes of Health (No. U54MD008602)the LSU Biomedical Collaborative Research Program+2 种基金funding support from the American Council on Exercisesupported in part by the National Institute of General Medical Sciences of the National Institutes of Health, which funds the Louisiana Clinical and Translational Science Center (No. U54 GM104940)supported in part by the NORC Center Grant entitled "Nutrition and Metabolic Health Through the Lifespan" sponsored by NIDDK (No. P30DK072476)
文摘Purpose: To examine the associations among preschoolers fundamental motor skills, screen-time, physical activity(PA), and sedentary behavior(SB).Methods: Children ages 3à4 years were enrolled in a prospective observational trial of PA. Trained assessors conducted the Test of Gross Motor Development-3 rd edition(TGMD-3), and the Movement Assessment Battery for Children-2 nd edition, and parent-reported child screen-time and sociodemographic information. Children wore an accelerometer for 7 days to examine SB and total PA(TPA). TPA was further characterized as moderateto-vigorous PA(MVPA) or vigorous PA(VPA). Mixed linear models were calculated, controlling for age(for TGMD-3), sex, household income, and accelerometer wear time(for accelerometry models), with childcare center as a random effect. The primary analysis reported on the cross-sectional baseline data of 126 children with complete fundamental motor skill and screen-time data; a subanalysis included 88 children with complete accelerometry data.Results: Children were 3.4 § 0.5 years of age(54% girls; 46% white, 42% African American, 12% other). A total of 48% lived in households at or below the federal poverty level. Children engaged in 5.1 § 3.6 h/day of screen-time. Children's screen-time was inversely related to the Movement Assessment Battery for Children-2 nd edition, manual dexterity skills percentile(b(SE) = ?1.7(0.8), p = 0.049). In the accelerometry subsample,children engaged in 5.9 § 0.9 h/day of TPA of which 1.7 § 0.6 h/day was MVPA. Boys engaged in more MVPA and VPA and less SB compared with girls(all p < 0.05). A higher TGMD-3, total score(b(SE) = 0.4(0.2), p = 0.017) and locomotor score(b(SE) = 0.7(0.3), p = 0.018) were associated with more VPA but not with TPA or MVPA. Screen-time and television in the bedroom were not related to SB, TPA, MVPA, or VPA.Conclusion: Children's motor skills were positively related to VPA but inversely related to screen-time. Further inquiry into the implications of high exposure to screen-time in young children is needed.
基金Projects (U1334201,51525804) supported by the National Natural Science Foundation of ChinaProject (15CXTD0005) supported by the Sichuan Province Youth Science and Technology Innovation Team,China
文摘In a wind-vehicle-bridge(WVB) system,there are various interactions among wind,vehicle and bridge.The mechanism for coupling vibration of wind-vehicle-bridge systems is explored to demonstrate the effects of fundamental factors,such as mean wind,fluctuating wind,buffeting,rail irregularities,light rail vehicle vibration and bridge stiffness.A long cable-stayed bridge which carries light rail traffic is regarded as a numerical example.Firstly,a finite element model is built for the long cable-stayed bridge.The deck can generally be idealized as three-dimensional spine beam while cables are modeled as truss elements.Vehicles are modeled as mass-spring-damper systems.Rail irregularities and wind fluctuation are simulated in time domain by spectrum representation method.Then,aerodynamic loads on vehicle and bridge deck are measured by section model wind tunnel tests.Eight vertical and torsional flutter derivatives of bridge deck are identified by weighting ensemble least-square method.Finally,dynamic responses of the WVB system are analyzed in a series of cases.The results show that the accelerations of the vehicle are excited by the fluctuating wind and the track irregularity to a great extent.The transverse forces of wheel axles mainly depend on the track irregularity.The displacements of the bridge are predominantly determined by the mean wind and restricted by its stiffness.And the accelerations of the bridge are enlarged after adding the fluctuating wind.
文摘A new type of hybrid finite element formulation with fundamental solutions as internal interpolation functions, named as HFS-FEM, is presented in this paper and used for solving two dimensional heat conduction problems in single and multi-layer materials. In the proposed approach, a new variational functional is firstly constructed for the proposed HFS-FE model and the related existence of extremum is presented. Then, the assumed internal potential field constructed by the linear combination of fundamental solutions at points outside the elemental domain under consideration is used as the internal interpolation function, which analytically satisfies the governing equation within each element. As a result, the domain integrals in the variational functional formulation can be converted into the boundary integrals which can significantly simplify the calculation of the element stiffness matrix. The independent frame field is also introduced to guarantee the inter-element continuity and the stationary condition of the new variational functional is used to obtain the final stiffness equations. The proposed method inherits the advantages of the hybrid Trefftz finite element method （HT-FEM） over the conventional finite element method （FEM） and boundary element method （BEM）, and avoids the difficulty in selecting appropriate terms of T-complete functions used in HT-FEM, as the fundamental solutions contain usually one term only, rather than a series containing infinitely many terms. Further, the fundamental solutions of a problem are, in general, easier to derive than the T-complete functions of that problem. Finally, several examples are presented to assess the performance of the proposed method, and the obtained numerical results show good numerical accuracy and remarkable insensitivity to mesh distortion.
文摘The present work describes the application of the method of fundamental solutions （MFS） along with the analog equation method （AEM） and radial basis function （RBF） approximation for solving the 2D isotropic and anisotropic Helmholtz problems with different wave numbers. The AEM is used to convert the original governing equation into the classical Poisson＇s equation, and the MFS and RBF approximations are used to derive the homogeneous and particular solutions, respectively. Finally, the satisfaction of the solution consisting of the homogeneous and particular parts to the related governing equation and boundary conditions can produce a system of linear equations, which can be solved with the singular value decomposition （SVD） technique. In the computation, such crucial factors related to the MFS-RBF as the location of the virtual boundary, the differential and integrating strategies, and the variation of shape parameters in multi-quadric （MQ） are fully analyzed to provide useful reference.
基金funded by an Agriculture and Food Research Initiative Competitive Grant #2010-85215-20648 from the United States Department of Agriculture (USDA) National Institute of Food and Agriculture
文摘Purpose: To identify the social-ecological correlates associated with fundamental movement skills at the child, family, and environment levels in young children.Methods: Preschool children from 4 Colorado Head Start/preschool centers were recruited from 2010 to 2012. Two hundred twenty-eight children(128 girls; age = 56.08 § 4.09 months; body mass index(BMI) z-score = 0.53 § 1.12(mean § SD); 42.1% Hispanic/Latino) and 159 families were included in the final analysis. Children's perceived competence and fundamental movement skills were assessed via the Pictorial Scale of Perceived Competence and Social Acceptance and the Bruininks-Oseretsky Test of Motor Proficiency, 2 nd edition. Data on the number of children in the family, parent age, BMI, education, employment status, family income, perception of child coordination, and home physical activity environment were collected via a questionnaire. Linear regressions adjusted for child BMI, age, sex, and school site were performed at each level.Results: Child perceived cognitive competence was positively associated with locomotor skills(p = 0.04; adjusted R2= 0.035) and object-control skills(p = 0.003; adjusted R2= 0.083) at the child level. Parent education, BMI, and perception of child coordination were positively associated with locomotor skills and explained 8.8% of variance, but only parent education was significant(p = 0.04) at the family level. In addition, physical environment was positively associated with locomotor skills(p = 0.02) and explained 5.5% of variance at the environment level.Conclusion: Social-ecological correlates associated with young children's fundamental movement skills are multidimensional and differ according to skill category at the child, family, and environment levels.
基金Project supported by the Innovation Fund of Space Technology.
文摘In this paper, adaptive genetic algorithm （AGA） is applied to topology optimization of truss structure with frequency domain excitations. The optimization constraints include fundamental frequency, displacement responses under force excitations and acceleration responses under foundation acceleration excitations. The roulette wheel selection operator, adaptive crossover and mutation operators are used as genetic operators. Some heuristic strategies are put forward to direct the deletion of the extra bars and nodes on truss structures. Three examples demonstrate that the proposed method can yield the optimum structure form and the lightest weight of the given ground structure while satisfying dynamic response constraints.
文摘Background:Physical activity(PA)in the early years is associated with a range of positive health outcomes.Fundamental motor skill(FMS)competence is associated with PA and is theorized to be driven by PA in the early years and vice versa in mid to late childhood.However,to date,no studies have meta-analyzed the association between PA and FMS in the early years.Methods:Six electronic databases were searched for articles published up to April 2019.Cross-sectional and longitudinal studies were included if they targeted children(ages 3-6 year)as the population of the study and assessed the association between objectively measured PA and FMS.Total FMS,total physical activity(TPA),and moderate-to-vigorous physical activity(MVPA)data were meta-analyzed using a random effects model.Results:We identified 24,815 titles and abstracts.In total,19 studies met the inclusion criteria,including 14 cross-sectional and 4 longitudinal studies,as well as 1 study with cross-sectional and longitudinal analysis.There was a significant but small positive association between FMS and MVPA(r=0.20,95%confidence interval(CI):0.13-0.26)and TPA(r=0.20,95%CI:0.12-0.28).Findings from longitudinal studies revealed that PA drives FMS in early childhood.Mediation was explored in 1 study,which found that perceived motor competence did not mediate the association between FMS and PA.Conclusion:Using a meta-analysis,this study is the first to show a positive association between FMS,MVPA,and TPA in the early years of childhood,suggesting that the association begins at an early age.Limited evidence from longitudinal studies supports the theory that PA drives FMS in the early years of childhood.More evidence is needed from large studies to track PA and FMS until mid to late childhood and to explore the mediators of this association.
文摘The highly conductive solid-state electrolytes (SSEs) have led to great progress in the development of all-solid-state batteries (ASSBs);however, there are obstacles to their application such as poor interfacial stability, scalability challenges, production safety and sustainability of ASSBs which still demand prompt solution. In Nature Nanotechnology, Tan and colleagues summarize solutions to overcome some major fundamental obstacles faced by the ASSB community。
基金financially supported by the Natural Science Foundation of China under grants: U20A20269, 51874106, and 51574092。
文摘Flotation is a complex process that occurs in solid-liquid-gas multiphase systems,and its main factors include the minerals,separation medium,as well as various flotation reagents.The study of mineral properties and interactions with other components such as reagents and water lays the basic theoretical foundation for flotation.Density functional theory(DFT) calculations can qualitatively evaluate the exchange of matter and energy between the mineral system and the surroundings and quantitatively characterize these behaviors,which greatly expands the breadth and depth of flotation studies.This review systematically summarizes the advances of flotation research based on DFT studies,including the study of mineral crystal chemistry represented by the theory of lattice defects,mineral surface hydration such as hydrophilicity and hydrophobicity,surface regulation mechanism,and collecting mechanism based on surface adsorption theory.More significantly,it systematically elaborates different types of collectors according to their characteristics and emphatically explains the mechanism of some typical collectors in detail.
