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Multi-Barycenter Mechanics, N-Body Problem and Rotation of Galaxies and Stars
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作者 Honglai Zhu 《Journal of Applied Mathematics and Physics》 2023年第10期3251-3273,共23页
In the present paper, the establishment of a systematic multi-barycenter mechanics is based on the multi-particle mechanics. The new theory perfects the basic theoretical system of classical mechanics, which finds the... In the present paper, the establishment of a systematic multi-barycenter mechanics is based on the multi-particle mechanics. The new theory perfects the basic theoretical system of classical mechanics, which finds the law of mutual interaction between particle groups, reveals the limitations of Newton’s third law, discovers the principle of the intrinsic relationship between gravity and tidal force, reasonably interprets the origin and change laws for the rotation angular momentum of galaxies and stars and so on. By applying new theory, the multi-body problem can be transformed into a special two-body problem and for which an approximate solution method is proposed, the motion law of each particle can be roughly obtained. 展开更多
关键词 Multi-Barycenter Mechanics Translation Principle for a Vector System Variation Principle for a Vector Origin and Change Laws for the Rotation Angular Momentum of Galaxies and Stars Multi-Body problem
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Centralized Circumcentered-Reection Method for Solving the Convex Feasibility Problem in Sparse Signal Recovery
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作者 Chunmei LI Bangjun CHEN Xuefeng DUAN 《Journal of Mathematical Research with Applications》 2026年第1期119-133,共15页
Convex feasibility problems are widely used in image reconstruction,sparse signal recovery,and other areas.This paper is devoted to considering a class of convex feasibility problem arising from sparse signal recovery... Convex feasibility problems are widely used in image reconstruction,sparse signal recovery,and other areas.This paper is devoted to considering a class of convex feasibility problem arising from sparse signal recovery.We rst derive the projection formulas for a vector onto the feasible sets.The centralized circumcentered-reection method is designed to solve the convex feasibility problem.Some numerical experiments demonstrate the feasibility and e ectiveness of the proposed algorithm,showing superior performance compared to conventional alternating projection methods. 展开更多
关键词 convex feasibility problem centralized circumcentered-re ection method sparse signal recovery compressed sensing
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Quality-guaranteed Dubins Path Planning for USV Based on Mixed-integer Piecewise linear Programming for Addressing the Extended Minimum-time Intercept Problem
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作者 Xing Zhou Kelin Zhu +3 位作者 Shuang Liu Zhaoqing Li Wenxin Zhang Kang Du 《哈尔滨工程大学学报(英文版)》 2026年第1期216-227,共12页
During the use of robotics in applications such as antiterrorism or combat,a motion-constrained pursuer vehicle,such as a Dubins unmanned surface vehicle(USV),must get close enough(within a prescribed zero or positive... During the use of robotics in applications such as antiterrorism or combat,a motion-constrained pursuer vehicle,such as a Dubins unmanned surface vehicle(USV),must get close enough(within a prescribed zero or positive distance)to a moving target as quickly as possible,resulting in the extended minimum-time intercept problem(EMTIP).Existing research has primarily focused on the zero-distance intercept problem,MTIP,establishing the necessary or sufficient conditions for MTIP optimality,and utilizing analytic algorithms,such as root-finding algorithms,to calculate the optimal solutions.However,these approaches depend heavily on the properties of the analytic algorithm,making them inapplicable when problem settings change,such as in the case of a positive effective range or complicated target motions outside uniform rectilinear motion.In this study,an approach employing a high-accuracy and quality-guaranteed mixed-integer piecewise-linear program(QG-PWL)is proposed for the EMTIP.This program can accommodate different effective interception ranges and complicated target motions(variable velocity or complicated trajectories).The high accuracy and quality guarantees of QG-PWL originate from elegant strategies such as piecewise linearization and other developed operation strategies.The approximate error in the intercept path length is proved to be bounded to h^(2)/(4√2),where h is the piecewise length. 展开更多
关键词 Minimum-time intercept problem Dubins vehicle Mixed-integer piecewise-linear program LINEARIZATION Approximate error trigonometric function USV
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Nested regular polygon solutions for planar 2N-body problems 被引量:3
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作者 张世清 周青 《Science China Mathematics》 SCIE 2002年第8期1053-1058,共6页
In this paper we study the necessary conditions for the masses of the nested regular polygon solutions of the planar 2N-body problem.We prove that the masses at the vertices of each regular polygon must be equal to ea... In this paper we study the necessary conditions for the masses of the nested regular polygon solutions of the planar 2N-body problem.We prove that the masses at the vertices of each regular polygon must be equal to each other. 展开更多
关键词 2n-body problems nested regular polygon periodic solutions circulant matrices
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Geometric characterization for the least Lagrangian action of n-body problems
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作者 张世清 周青 《Science China Mathematics》 SCIE 2001年第1期15-20,共6页
For n-body problems with quasihomogeneous potentials in ?k (2[ n/2] ? k) we prove that the minimum of the Lagrangian action integral defined on the zero mean loop space is exactly the circles with center at the origin... For n-body problems with quasihomogeneous potentials in ?k (2[ n/2] ? k) we prove that the minimum of the Lagrangian action integral defined on the zero mean loop space is exactly the circles with center at the origin and the configuration of the n-bodies is always a regular n - 1 simplex with fixed side length. 展开更多
关键词 n-body problems Lagrangian action integral homographic solutions
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Difference Equation for N-body Type Problem
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作者 Xu LE-SHUN HAN YUE-CAI LIU BAI-FENG 《Communications in Mathematical Research》 CSCD 2009年第5期411-417,共7页
In this paper, the difference equation for N-body type problem is established, which can be used to find the generalized solutions by computing the critical points numerically. And its validity is testified by an exam... In this paper, the difference equation for N-body type problem is established, which can be used to find the generalized solutions by computing the critical points numerically. And its validity is testified by an example from Newtonian Threebody problem with unequal masses. 展开更多
关键词 Difference equation n-bodytype problem critical point
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On Waring-Goldbach Problem for Two Squares, Two Cubes and Two Fifth Powers
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作者 LI Jinjiang ZHAO Chenyang +1 位作者 LIU Zishun ZHANG Min 《数学进展》 北大核心 2025年第4期735-748,共14页
Let Pr denote an almost-prime with at most r prime factors,counted according to multiplicity.In this paper,it is proved that,for every sufficiently large even integer N,the equation N=x^(2)+p_(2)^(2)+p_(3)^(3)+p_(4)^(... Let Pr denote an almost-prime with at most r prime factors,counted according to multiplicity.In this paper,it is proved that,for every sufficiently large even integer N,the equation N=x^(2)+p_(2)^(2)+p_(3)^(3)+p_(4)^(3)+p_(5)^(5)+_6^(5)is solvable with being an almost-prime P_(6) and the other variables primes.This result constitutes an enhancement upon the previous result of Hooley[Recent Progress in Analytic Number Theory,Vol.1(Durham,1979),London:Academic Press,1981,127-191]. 展开更多
关键词 Waring-Goldbach problem Hardy-Littlewood method almost-prime sieve method
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On the Divisor Problem with Congruence Conditions
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作者 JIA Lirui ZHAI Wenguang CAI Tianxin 《数学进展》 北大核心 2025年第1期1-17,共17页
Let d(n;r_(1),q_(1),r_(2),q_(2))be the number of factorization n=n_(1)n_(2)satisfying n_i≡r_i(mod q_i)(i=1,2)andΔ(x;r_(1),q_(1),r_(2),q_(2))be the error term of the summatory function of d(n;r_(1),q_(1),r_(2),q_(2))... Let d(n;r_(1),q_(1),r_(2),q_(2))be the number of factorization n=n_(1)n_(2)satisfying n_i≡r_i(mod q_i)(i=1,2)andΔ(x;r_(1),q_(1),r_(2),q_(2))be the error term of the summatory function of d(n;r_(1),q_(1),r_(2),q_(2)).Suppose x≥(q_(1)q_(2))^(1+ε),1≤r_i≤q_i,and(r_i,q_i)=1(i=1,2).This paper studies the power moments and sign changes ofΔ(x;r_(1),q_(1),r_(2),q_(2)).We prove that for sufficiently large constant C,Δ(q_(1)q_(2)x:r_(1),q_(1),r_(2),q_(2))changes sign in the interval[T,T+C√T]for any large T.Meanwhile,we show that for small constants c and c,there exist infinitely many subintervals of length c√log^(-7)T in[T,2T]where±Δ(q_(1)q_(2)x:r_(1),q_(1),r_(2),q_(2))>cx^(1/4)always holds. 展开更多
关键词 divisor problem sign change congruence condition
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A unified M-tree self-correction solver for math word problems
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作者 Zhiyuan Ma Jiayu Liu Zhenya Huang 《中国科学技术大学学报》 北大核心 2025年第7期26-35,25,I0001,共12页
Automatically answer math word problems is a challenging task in artificial intelligence.Previous solvers constructed mathematical expressions in sequence or binary tree.However,these approaches may suffer from the fo... Automatically answer math word problems is a challenging task in artificial intelligence.Previous solvers constructed mathematical expressions in sequence or binary tree.However,these approaches may suffer from the following issues:Models relying on such structures exhibit fixed-order reasoning(e.g.,left-to-right),limiting flexibility and increasing error susceptibility;prior models rely on autoregressive reasoning in a single pass,accumulating minor errors(e.g.,incorrect math symbols)during generation,resulting in reduced accuracy.To address the above issues,we emulate the human“check and modify”process in reasoning and propose a unified M-tree self-correction solver(UTSCSolver)by iterative inference with self-correction mechanism.First,we use an iterative,non-autoregressive process for generating mathematical expressions,free from fixed generation orders to handle complex and diverse problems.Additionally,we design a self-correction mechanism based on alternating execution between a generator and a discriminator.This module iteratively detects and rectifies errors in generated expressions,leveraging previous iteration information for subsequent generation guidance.Experimental results show that our UTSC-Solver outperforms traditional models in accuracy on two popular datasets,while it improves the interpretability of mathematical reasoning. 展开更多
关键词 mathematical reasoning non-autoregressive generation math word problems
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Relationship between parenting stress and behavioral and emotional problems in preschool children: A mediation effect analysis
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作者 Zhi-Wei Fu Yue-Jing Li +3 位作者 Ran Yu Rui-Qing Guo Li-Xia Gao Sheng-Xia Zhao 《World Journal of Psychiatry》 SCIE 2025年第1期128-136,共9页
BACKGROUND Emotional reactions,such as anxiety,irritability,and aggressive behavior,have attracted clinical attention as behavioral and emotional problems in preschool-age children.AIM To investigate the current statu... BACKGROUND Emotional reactions,such as anxiety,irritability,and aggressive behavior,have attracted clinical attention as behavioral and emotional problems in preschool-age children.AIM To investigate the current status of family rearing,parental stress,and behavioral and emotional problems of preschool children and to analyze the mediating effect of the current status of family rearing on parental stress and behavioral/emo-tional problems.METHODS We use convenience sampling to select 258 preschool children in the physical examination center of our hospital from October 2021 to September 2023.The children and their parents were evaluated using a questionnaire survey.Pearson's correlation was used to analyze the correlation between child behavioral and emotional problems and parental stress and family rearing,and the structural equation model was constructed to test the mediating effect.RESULTS The score for behavioral/emotional problems of 258 preschool children was(27.54±3.63),the score for parental stress was(87.64±11.34),and the score for parental family rearing was(31.54±5.24).There was a positive correlation between the behavioral and emotional problems of the children and the“hostile/mandatory”parenting style;meanwhile,showed a negative correlation with the“support/participation”parenting style(all P<0.05).The intermediary effect value between the family upbringing of parents in parental stress and children's behavior problems was 29.89%.CONCLUSION Parental family upbringing has a mediating effect between parental stress and behavioral and emotional problems of children.Despite paying attention to the behavioral and emotional problems of preschool-age children,clinical medical staff should provide correct and reasonable parenting advice to their parents to promote the mental health of preschool-age children. 展开更多
关键词 Preschool children Parenting stress Children's behavioral and emotional problems Family rearing Mediating effect
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Efficacy of School-Based Interventions to Manage Psychosocial Problems of an Adolescent: A Clinical Case Study
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作者 Dua Fatima Afzaal Farhan Hashmi 《Open Journal of Medical Psychology》 2025年第1期19-31,共13页
This case study explores the efficacy of school-based intervention to address psychosocial challenges faced by an 11-year-old adolescent. The case study aimed to decrease the agression and acting out behavior as resul... This case study explores the efficacy of school-based intervention to address psychosocial challenges faced by an 11-year-old adolescent. The case study aimed to decrease the agression and acting out behavior as result of being victimized at school by the peers. The aim was to assess and manage the child’s aggressive behavior and academic underperformance which played a significant role in the child’s low self-esteem and emotional regulation. A comprehensive assessment was conducted to rule out the difficulties and a multi-faceted intervention strategy was utilized including anger management and structured activity scheduling that helped that child to improve his academic performance as well as to learn to manage his emotional expression. Throughout 16 sessions, the intervention targeted key behavioural indicators such as emotional expression, and aggression;post-assessment results demonstrated a 22% improvement in the child’s behavioral and academic challenges. The findings suggest that a multi-faceted therapeutic approach can be effective in addressing complex issues of aggression and academic underperformance in children, highlighting the importance of integrated psychological and educational interventions. 展开更多
关键词 AGGRESSION School-Related problems BULLYING VICTIMIZATION Cognitive-Behavioral Therapy
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Information-Body Relation and Information as a Solution of the Consciousness Problem in the Biological Structures
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作者 Florin Gaiseanu 《Journal of Philosophy Study》 2022年第5期287-303,共17页
This paper approaches two main philosophical questions concerning the biological structures,from unicellular to multicellular organisms:one of them(i),referred to the information-body relation,as an extension of the m... This paper approaches two main philosophical questions concerning the biological structures,from unicellular to multicellular organisms:one of them(i),referred to the information-body relation,as an extension of the mind-body relation at human,and another one(ii),to the consciousness problem,concerning the existence and nature of consciousness(if any),at the inferior organisms on the complexity scale,as this concept is known at humans.As philosophy benefits of the privilege to use data/concepts from other sciences to obtain philosophical conclusions,there were included detailed descriptions of some key biologic mechanisms,analyzed from informational perspective,necessary just to support/demonstrate/reinforce the informational nature/substrate of the mentioned relations.The analysis of the close relation between information and body,related to the structuration and functional properties of the biological organisms,from cells to multicellular structures,shows that all of them are able to“embody/disembody”information during/by structuration/destructuration processes of matter,in particular that of DNA/RNA/proteins,their functions appearing as a result of their informational capabilities to internally manage the inter-connection with environment,primarily due to their permanent dependence on the food resources and adaptation/survival needs.The experimental and theoretical studies,revealing/documenting on one hand the automatic management of maintenance metabolic processes,the reproduction,and growth/development,and on the other hand the adaptive decision-making/sentient processes as a responsive reaction to the environmental cues,show/support the consistency of the informational model of the human body and living structures on the entire biological scale,providing support to the informational solution of the stated problems(i)and(ii).A distinct attention is paid to plants,which are organisms without nervous system,but which show/manifest also informational capabilities to detect/react to information and to modulate their behavior accordingly.The question if the living organisms possess a pseudo/proto-consciousness level as a consequence of the informational activity of their body,distinct from human,but active in any biological structure under certain conditions is furthermore discussed,and a reliable definition of rudimentary pseudo/proto-consciousness level is given/described and compared with other empirical/theoretical concepts. 展开更多
关键词 information in biological structures informationally-driven processes structuration/destructuration growth/differentiation/maintenance functionality/informational structure info-intra/inter-communication cognitive centers proto/pseudo-consciousness problem
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Programming guide for solving constraint satisfaction problems with tensor networks
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作者 Xuanzhao Gao Xiaofeng Li Jinguo Liu 《Chinese Physics B》 2025年第5期71-90,共20页
Constraint satisfaction problems(CSPs)are a class of problems that are ubiquitous in science and engineering.They feature a collection of constraints specified over subsets of variables.A CSP can be solved either dire... Constraint satisfaction problems(CSPs)are a class of problems that are ubiquitous in science and engineering.They feature a collection of constraints specified over subsets of variables.A CSP can be solved either directly or by reducing it to other problems.This paper introduces the Julia ecosystem for solving and analyzing CSPs with a focus on the programming practices.We introduce some important CSPs and show how these problems are reduced to each other.We also show how to transform CSPs into tensor networks,how to optimize the tensor network contraction orders,and how to extract the solution space properties by contracting the tensor networks with generic element types.Examples are given,which include computing the entropy constant,analyzing the overlap gap property,and the reduction between CSPs. 展开更多
关键词 tensor networks constraint satisfaction problems problem reductions Julia
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Direct and Inverse Problems for a Third-order Differential Operator with Anti-periodic Boundary Conditions and a Non-local Potential
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作者 ZHANG Mingming LIU Yixuan 《数学理论与应用》 2025年第1期62-80,共19页
This paper focuses on the direct and inverse problems for a third-order self-adjoint differential operator with non-local potential and anti-periodic boundary conditions.Firstly,we obtain the expressions for the chara... This paper focuses on the direct and inverse problems for a third-order self-adjoint differential operator with non-local potential and anti-periodic boundary conditions.Firstly,we obtain the expressions for the characteristic function and resolvent of this third-order differential operator.Secondly,by using the expression for the resolvent of the operator,we prove that the spectrum for this operator consists of simple eigenvalues and a finite number of eigenvalues with multiplicity 2.Finally,we solve the inverse problem for this operator,which states that the non-local potential function can be reconstructed from four spectra.Specially,we prove the Ambarzumyan theorem and indicate that odd or even potential functions can be reconstructed by three spectra. 展开更多
关键词 Direct problem Inverse problem Non-local potential Anti-periodic boundary condition
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On the Riemann-Hilbert problem for the reverse space-time nonlocal Hirota equation with step-like initial data
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作者 Bei-Bei Hu Ling Zhang +1 位作者 Zu-Yi Shen Ji Lin 《Communications in Theoretical Physics》 2025年第2期30-38,共9页
In this paper,we use the Riemann-Hilbert(RH)method to investigate the Cauchy problem of the reverse space-time nonlocal Hirota equation with step-like initial data:q(z,0)=o(1)as z→-∞and q(z,0)=δ+o(1)as z→∞,where... In this paper,we use the Riemann-Hilbert(RH)method to investigate the Cauchy problem of the reverse space-time nonlocal Hirota equation with step-like initial data:q(z,0)=o(1)as z→-∞and q(z,0)=δ+o(1)as z→∞,whereδis an arbitrary positive constant.We show that the solution of the Cauchy problem can be determined by the solution of the corresponding matrix RH problem established on the plane of complex spectral parameterλ.As an example,we construct an exact solution of the reverse space-time nonlocal Hirota equation in a special case via this RH problem. 展开更多
关键词 nonlocal Hirota equation Cauchy problem Riemann-Hilbert problem step-like initial data
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Study on Current Situation,Existing Problems and Countermeasures of Soybean Cultivation
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作者 Huajun SUN 《Agricultural Biotechnology》 2025年第1期9-12,18,共5页
As one of the world's three major food crops and an important economic and oil crop,soybean plays a crucial role in ensuring food safety.In recent years,there are many problems in soybean cultivation,production an... As one of the world's three major food crops and an important economic and oil crop,soybean plays a crucial role in ensuring food safety.In recent years,there are many problems in soybean cultivation,production and processing.In view of this situation,this paper comprehensively expounded and decomposed the cultivation situation,existing problems,specific countermeasures and conclusions,so as to re-recognize them.This study provides reference materials for the sustainable and healthy development of the soybean industry. 展开更多
关键词 SOYBEAN Cultivation situation problemS COUNTERMEASURE
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Solve the Word Problems of Maths
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作者 杨哲 《疯狂英语(双语世界)》 2025年第3期44-46,68,共4页
1.The price of a desk is 10 times the price of a chair.The desk costs 288 yuan more than the chair.How much does one desk and one chair cost?2.A and B start from two different places and walk toward each other.After 4... 1.The price of a desk is 10 times the price of a chair.The desk costs 288 yuan more than the chair.How much does one desk and one chair cost?2.A and B start from two different places and walk toward each other.After 4 hours,they meet at a point that is 4 kilometres away from the midpoint between their starting points.A walks faster than B.How many more kilometres per hour does A walk than B? 展开更多
关键词 COST DISTANCE word problems MATHS PRICE SPEED
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A neural network based on novel equivalent model for linear complementarity problems
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作者 KE Yi-fen XIE Ya-jun +1 位作者 ZHANG Huai MA Chang-feng 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第2期311-326,共16页
A family of neural networks is proposed to solve linear complementarity problems(LCP).The neural networks are constructed from the novel equivalent model of LCP,which is reformulated by utilizing the modulus and smoot... A family of neural networks is proposed to solve linear complementarity problems(LCP).The neural networks are constructed from the novel equivalent model of LCP,which is reformulated by utilizing the modulus and smoothing technologies.Some important properties of the proposed novel equivalent model are summarized.In addition,the stability properties of the proposed steepest descent-based neural networks for LCP are analyzed.In order to illustrate the theoretical results,we provide some numerical simulations and compare the proposed neural networks with existing neural networks based on the NCP-functions.Numerical results indicate that the performance of the proposed neural networks is effective and robust. 展开更多
关键词 linear complementarity problem neural network MODULUS STABILITY
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The Orlicz Minkowski Problem for Logarithmic Capacity
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作者 HE Min LIU Lijuan ZENG Hui 《Wuhan University Journal of Natural Sciences》 2025年第5期471-478,共8页
The Orlicz Minkowski problem for logarithmic capacity seeks to determine the necessary and sufficient conditions for a given finite Borel measure,such that it is the Orlicz logarithmic capacitary measure of a convex b... The Orlicz Minkowski problem for logarithmic capacity seeks to determine the necessary and sufficient conditions for a given finite Borel measure,such that it is the Orlicz logarithmic capacitary measure of a convex body.The Orlicz Minkowski problem for loga-rithmic capacity includes the Minkowski problem for logarithmic capacity and the Lp Minkowski problem for logarithmic capacity as special cases.The discrete case has been solved by the researchers.In this paper,we solve the Orlicz Minkowski problem for logarithmic capacity with respect to general Borel measures by applying an approximation scheme. 展开更多
关键词 Orlicz Minkowski problem capacity convex body
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Problems and Coping Strategies of Mechanical Drawing Courses in Vocational Colleges
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作者 Jinru Ma 《Journal of Contemporary Educational Research》 2025年第5期122-127,共6页
With the economic and social development of the country,vocational education is playing an increasingly significant role in cultivating highly skilled talents.However,the mechanical drawing courses in vocational colle... With the economic and social development of the country,vocational education is playing an increasingly significant role in cultivating highly skilled talents.However,the mechanical drawing courses in vocational colleges still face numerous challenges in the teaching process,such as outdated textbook content,inadequate practical resources,weak teaching staff,and low student interest.This paper aims to explore these issues and propose corresponding coping strategies.The findings of this study not only provide specific improvement suggestions for vocational colleges but also emphasize the importance of these strategies in enhancing students’comprehensive abilities and promoting the development of vocational education.By addressing these challenges,this paper contributes to the enhancement of teaching quality and the overall advancement of vocational skills education. 展开更多
关键词 Mechanical Drawing courses Mechanical drawing problemS STRATEGIES
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