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A new algorithm for designing developable Bézier surfaces 被引量:3
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作者 ZHANG Xing-wang WANG Guo-jin 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第12期2050-2056,共7页
A new algorithm is presented that generates developable Bézier surfaces through a Bézier curve called a directrix. The algorithm is based on differential geometry theory on necessary and sufficient condition... A new algorithm is presented that generates developable Bézier surfaces through a Bézier curve called a directrix. The algorithm is based on differential geometry theory on necessary and sufficient conditions for a surface which is developable, and on degree evaluation formula for parameter curves and linear independence for Bernstein basis. No nonlinear characteristic equations have to be solved. Moreover the vertex for a cone and the edge of regression for a tangent surface can be obtained easily. Aumann’s algorithm for developable surfaces is a special case of this paper. 展开更多
关键词 Bézier surfaces developable surfaces Bemstein basis Linear independence Characteristic equations
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Feedback Mechanism-driven Mutation Reptile Search Algorithm for Optimizing Interpolation Developable Surfaces
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作者 Gang Hu Jiao Wang +1 位作者 Xiaoni Zhu Muhammad Abbas 《Journal of Bionic Engineering》 SCIE EI CSCD 2024年第1期527-571,共45页
Curvature lines are special and important curves on surfaces.It is of great significance to construct developable surface interpolated on curvature lines in engineering applications.In this paper,the shape optimizatio... Curvature lines are special and important curves on surfaces.It is of great significance to construct developable surface interpolated on curvature lines in engineering applications.In this paper,the shape optimization of generalized cubic ball developable surface interpolated on the curvature line is studied by using the improved reptile search algorithm.Firstly,based on the curvature line of generalized cubic ball curve with shape adjustable,this paper gives the construction method of SGC-Ball developable surface interpolated on the curve.Secondly,the feedback mechanism,adaptive parameters and mutation strategy are introduced into the reptile search algorithm,and the Feedback mechanism-driven improved reptile search algorithm effectively improves the solving precision.On IEEE congress on evolutionary computation 2014,2017,2019 and four engineering design problems,the feedback mechanism-driven improved reptile search algorithm is compared with other representative methods,and the result indicates that the solution performance of the feedback mechanism-driven improved reptile search algorithm is competitive.At last,taking the minimum energy as the evaluation index,the shape optimization model of SGC-Ball interpolation developable surface is established.The developable surface with the minimum energy is achieved with the help of the feedback mechanism-driven improved reptile search algorithm,and the comparison experiment verifies the superiority of the feedback mechanism-driven improved reptile search algorithm for the shape optimization problem. 展开更多
关键词 Reptile search algorithm Feedback mechanism Adaptive parameter Mutation strategy SGC-Ball interpolation developable surface Shape optimization
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Method of designing developable surface based on engineering requirement
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作者 杨继新 刘哲 刘健 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第2期215-218,共4页
The paper deals with the principle of envelope of a one-parameter plane family to design developable surfaces. Three methods of designing developable surfaces are presented. They are designing a developable surface ba... The paper deals with the principle of envelope of a one-parameter plane family to design developable surfaces. Three methods of designing developable surfaces are presented. They are designing a developable surface based on one curve on it and its normal line, designing a developable surface based on two curves on it and designing a developable surface based on one curve and one surface. They meet the requirements of engineering fields. 展开更多
关键词 developable surface CURVE curved face
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Determination and(Re)Parametrization of Rational Developable Surfaces 被引量:3
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作者 SHEN Liyong PREZ-DíAZ Sonia 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2015年第6期1426-1439,共14页
The developable surface is an important surface in computer aided design, geometric modeling and industrial manufactory. It is often given in the standard parametric form, but it can also be in the implicit form which... The developable surface is an important surface in computer aided design, geometric modeling and industrial manufactory. It is often given in the standard parametric form, but it can also be in the implicit form which is commonly used in algebraic geometry. Not all algebraic developable surfaces have rational parametrizations. In this paper, the authors focus on the rational developable surfaces. For a given algebraic surface, the authors first determine whether it is developable by geometric inspection, and then give a rational proper parametrization in the affrmative case. For a rational parametric surface, the authors also determine the developability and give a proper reparametrization for the developable surface. 展开更多
关键词 PARAMETRIZATION PROPER rational developable surface reparametrization
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Interpolation of a spline developable surface between a curve and two rulings 被引量:1
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作者 Alicia CANTóN Leonardo FERNáNDEZ-JAMBRINA 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2015年第3期173-190,共18页
In this paper we address the problem of interpolating a spline developable patch bounded by a given spline curve and the first and the last rulings of the developable surface. To complete the boundary of the patch, a ... In this paper we address the problem of interpolating a spline developable patch bounded by a given spline curve and the first and the last rulings of the developable surface. To complete the boundary of the patch, a second spline curve is to be given. Up to now this interpolation problem could be solved, but without the possibility of choosing both endpoints for the rulings. We circumvent such difficulty by resorting to degree elevation of the developable surface. This is useful for solving not only this problem, but also other problems dealing with triangular developable patches. 展开更多
关键词 developable surfaces Spline surfaces BLOSSOMS
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DEVELOPABLE SURFACE PATCHES BOUNDED BY NURBS CURVES 被引量:1
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作者 Leonardo Fernandez-Jambrina Francisco Perez-Arribas 《Journal of Computational Mathematics》 SCIE CSCD 2020年第5期715-731,共17页
In this paper we construct developable surface patches which are bounded by two rational or NURBS curves,though the resulting patch is not a rational or NURBS surface in general.This is accomplished by reparameterizin... In this paper we construct developable surface patches which are bounded by two rational or NURBS curves,though the resulting patch is not a rational or NURBS surface in general.This is accomplished by reparameterizing one of the boundary curves.The reparameterization function is the solution of an algebraic equation.For the relevant case of cubic or cubic spline curves,this equation is quartic at most,quadratic if the curves are B´ezier or splines and lie on parallel planes,and hence it may be solved either by standard analytical or numerical methods. 展开更多
关键词 NURBS B´ezier Rational Spline NURBS developable surfaces
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mTORC1 and mTORC2 synergy in human neural development, disease, and regeneration 被引量:1
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作者 Navroop K.Dhaliwal Julien Muffat Yun Li 《Neural Regeneration Research》 2026年第4期1552-1553,共2页
The mechanistic target of rapamycin(m TOR) is a serine/threonine kinase that plays a pivotal role in cellular growth, proliferation, survival, and metabolism. In the central nervous system(CNS), the mTOR pathway regul... The mechanistic target of rapamycin(m TOR) is a serine/threonine kinase that plays a pivotal role in cellular growth, proliferation, survival, and metabolism. In the central nervous system(CNS), the mTOR pathway regulates diverse aspects of neural development and function. Genetic mutations within the m TOR pathway lead to severe neurodevelopmental disorders, collectively known as “mTORopathies”(Crino, 2020). Dysfunctions of m TOR, including both its hyperactivation and hypoactivation, have also been implicated in a wide spectrum of other neurodevelopmental and neurodegenerative conditions, highlighting its importance in CNS health. 展开更多
关键词 m tor neural development mtorc central nervous system cns mtor neurodevelopmental disorders neurodegenerative conditions
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Research progress on chemical synthesis of biomassbased hydrocarbon fuels
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作者 WU Pengjun CHEN Xinyang +3 位作者 DAI Yitong FENG Jingke FANG Wenjun GUO Yongsheng 《燃料化学学报(中英文)》 北大核心 2026年第2期1-20,共20页
Biomass-based hydrocarbon fuels,as one of the alternatives to traditional fossil fuels,have attracted considerable attention in the energy field due to their renewability and environmental benefits.This article provid... Biomass-based hydrocarbon fuels,as one of the alternatives to traditional fossil fuels,have attracted considerable attention in the energy field due to their renewability and environmental benefits.This article provides a systematic review of recent research progress in the chemical synthesis of biomass-based hydrocarbon fuels.It outlines the conversion pathways using feedstocks such as lipids,terpenoids,cellulose/hemicellulose,and lignin.Depending on the feedstock,various products with distinct structural characteristics can be prepared through reactions such as cyclization,condensation,and catalytic hydrogenation.Throughout the synthesis process,three key factors play a critical role:efficient catalyst development,production process optimization,and computational-chemistry-based molecular design.Finally,the article discusses future perspectives for biomass-based hydrocarbon fuel synthesis research. 展开更多
关键词 BIOMASS hydrocarbon fuel catalyst development process optimization molecular design computational chemistry
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Statistics and Development Analysis of Urban Rail Transit in China by the End of 2025
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作者 WANG Fuwen LIANG Shuaiwen FENG Aijun 《隧道建设(中英文)》 北大核心 2026年第2期437-444,I0005-I0012,共16页
First,statistics on the operational lines and mileage of urban rail transit in China are conducted.The results show that,as of Dec.31,2025,there were 60 cities with urban rail transit in operation nationwide,with a to... First,statistics on the operational lines and mileage of urban rail transit in China are conducted.The results show that,as of Dec.31,2025,there were 60 cities with urban rail transit in operation nationwide,with a total operational mileage of approximately 12837.8 km(excluding the electronic guideway rubber-tired system,there were 57 cities,with a total operational mileage of 12651.6 km).The metro system dominates,while low-capacity systems exhibit a multi-modal development pattern.Subsequently,the characteristics of China′s urban rail transit industry development are analyzed,indicating that:(1)It should closely align with the theme of urban intensive development,promote quality improvement and efficiency enhancement of existing lines,and focus on the supporting role of initial passenger flow for new line construction,multi-network integration,and economic and financial sustainability.(2)Significant innovative achievements have been made in safety resilience,green and low-carbon development,intelligent construction,and digital transformation.Finally,development recommendations for the"15th Five-Year Plan"period are proposed:promoting cost reduction and efficiency improvement in the rail transit industry,enhancing the operational efficiency of existing networks,continuously exploring railway services for urban commuting,strengthening external exchanges,and driving the"going global"strategy of the urban rail transit industry. 展开更多
关键词 rail transit operational lines data statistics development analysis
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Innovation and Development Policy(中文名:《创新与发展政策(英文)》)征稿启事
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《科研管理》 北大核心 2026年第1期F0004-F0004,共1页
Innovation and Development Policy,简称“IDP”,中文名:《创新与发展政策(英文)》,是由中国科学院主管,中国科学院科技战略咨询研究院、中国科学学与科技政策研究会共同主办,国内外发行(ISSN:2096-5141,CN:10-1513/D)的英文国际期刊... Innovation and Development Policy,简称“IDP”,中文名:《创新与发展政策(英文)》,是由中国科学院主管,中国科学院科技战略咨询研究院、中国科学学与科技政策研究会共同主办,国内外发行(ISSN:2096-5141,CN:10-1513/D)的英文国际期刊。目前期刊每年出版两期。已发表论文在期刊网站可以自由获取,http://idp-journal.casisd.cn/browse/al/al2019/。 展开更多
关键词 创新与发展政策 Innovation and Development Policy
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CHARACTERISATION OF RATIONAL AND NURBS DEVELOPABLE SURFACES IN COMPUTER AIDED DESIGN
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作者 Leonardo Fernandez-Jambrina 《Journal of Computational Mathematics》 SCIE CSCD 2021年第4期556-573,共18页
In this paper we provide a characterisation of rational developable surfaces in terms of the blossoms of the bounding curves and three rational functions∧,M,ν.Properties of developable surfaces are revised in this f... In this paper we provide a characterisation of rational developable surfaces in terms of the blossoms of the bounding curves and three rational functions∧,M,ν.Properties of developable surfaces are revised in this framework.In particular,a closed algebraic formula for the edge of regression of the surface is obtained in terms of the functions∧,M,ν,which are closely related to the ones that appear in the standard decomposition of the derivative of the parametrisation of one of the bounding curves in terms of the director vector of the rulings and its derivative.It is also shown that all rational developable surfaces can be described as the set of developable surfaces which can be constructed with a constant∧,M,ν.The results are readily extended to rational spline developable surfaces. 展开更多
关键词 NURBS BEZIER RATIONAL SPLINE NURBS developable surfaces
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Tangential Developable Surfaces as Bonnet Surfaces
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作者 Ioannis M. Roussos, Department of Mathematics, Hamline University, Saint Paul, MN 55104-1284, U. S. AE-mail: iroussos@seq.hamline, edu 《Acta Mathematica Sinica,English Series》 SCIE CSCD 1999年第2期269-276,共8页
We study the real Bonnet surfaces which accept one unique nontrivial isometry that preserves the mean curvature, in the three-dimensional Euclidean space. We give a general criterion for these surfaces and use it to d... We study the real Bonnet surfaces which accept one unique nontrivial isometry that preserves the mean curvature, in the three-dimensional Euclidean space. We give a general criterion for these surfaces and use it to determine the tangential developable surfaces of this kind. They are determined implicitly by elliptic integrals of the third kind. Only the tangential developable surfaces of circular helices are explicit examples for which we completely determine the above unique nontrivial isometry. 展开更多
关键词 Bonnet surface Mean curvature ISOMETRY Tangential developable Elliptic integral Circular helix
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Quasi-Developable B-Spline Surface Design with Control Rulings
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作者 Zi-Xuan Hu Peng-Bo Bo Cai-Ming Zhang 《Journal of Computer Science & Technology》 SCIE EI CSCD 2022年第5期1221-1238,共18页
We propose a method for generating a ruled B-spline surface fitting to a sequence of pre-defined ruling lines and the generated surface is required to be as-developable-as-possible.Specifically,the terminal ruling lin... We propose a method for generating a ruled B-spline surface fitting to a sequence of pre-defined ruling lines and the generated surface is required to be as-developable-as-possible.Specifically,the terminal ruling lines are treated as hard constraints.Different from existing methods that compute a quasi-developable surface from two boundary curves and cannot achieve explicit ruling control,our method controls ruling lines in an intuitive way and serves as an effective tool for computing quasi-developable surfaces from freely-designed rulings.We treat this problem from the point of view of numerical optimization and solve for surfaces meeting the distance error tolerance allowed in applications.The performance and the efficacy of the proposed method are demonstrated by the experiments on a variety of models including an application of the method for path planning in 5-axis computer numerical control(CNC)flank milling. 展开更多
关键词 developable surface surface modeling B-spline surface numerical optimization
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Ecosystem management and agricultural green development in subtropical regions
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作者 Jinshui Wu Tony G.O’Donnell +4 位作者 Andrew Macrae Hongsong Chen Weiguo Cheng Zhihong Xu Zhengmiao Deng 《Journal of Integrative Agriculture》 2026年第2期399-401,共3页
The United Nations Sustainable Development Goal(SDG) 2 aims to achieve Zero Hunger by 2030.However,global hunger and food insecurity have continued to rise at an alarming rate(UN 2023).Subtropical regions are home to ... The United Nations Sustainable Development Goal(SDG) 2 aims to achieve Zero Hunger by 2030.However,global hunger and food insecurity have continued to rise at an alarming rate(UN 2023).Subtropical regions are home to more than 30% of the world's population,predominantly in developing countries where per capita farmland and food supply are only 40% of those in developed nations(FAO 2018).Meeting the Zero Hunger target amid ongoing population growth in these regions requires a substantial increase in agricultural production while minimizing soil degradation and adverse ecological impacts.This challenge is shared by many countries across South Asia,Africa,and Central and South America. 展开更多
关键词 ecosystem management developing countries subtropical regions sustainable development goal agricultural green development zero hunger sustainable development goal sdg population growth
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Caustics of developable surfaces
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作者 Miklos HOFFMANN Imre JUHASZ Ede TROLL 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2022年第3期479-487,共9页
While considering a mirror and light rays coming either from a point source or from infinity,the reflected light rays may have an envelope,called a caustic curve.In this paper,we study developable surfaces as mirrors.... While considering a mirror and light rays coming either from a point source or from infinity,the reflected light rays may have an envelope,called a caustic curve.In this paper,we study developable surfaces as mirrors.These caustic surfaces,described in a closed form,are also developable surfaces of the same type as the original mirror surface.We provide efficient,algorithmic computation to find the caustic surface of each of the three types of developable surfaces(cone,cylinder,and tangent surface of a spatial curve).We also provide a potential application of the results in contemporary free-form architecture design. 展开更多
关键词 CAUSTICS developable surface Reflected light rays Curve of regression
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Guiding the younger generation to explore new scenarios for participating in standards development and application
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作者 Li Zhiping 《China Standardization》 2026年第1期43-44,共2页
Standards are the common language that consolidates global consensus and builds the most solid foundation for international partnerships.They are the cornerstone for global sustainable and high-quality development.You... Standards are the common language that consolidates global consensus and builds the most solid foundation for international partnerships.They are the cornerstone for global sustainable and high-quality development.Young students,with their active and vibrant minds,represent the future and hope of standardization. 展开更多
关键词 standards development sustainable development application standards international partnerships high quality development consolidates global consensus younger generation common language
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Bridging Dreams,Building Futures
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《ChinAfrica》 2026年第3期14-15,共2页
China-Zimbabwe collaboration is creating new opportunities for innovation and development of youth Zimbabwe’s development has long faced obstacles linked to Western economic sanctions,measures that many view as unjus... China-Zimbabwe collaboration is creating new opportunities for innovation and development of youth Zimbabwe’s development has long faced obstacles linked to Western economic sanctions,measures that many view as unjust or unlawful.Yet,despite these constraints,Zimbabwe remains a nation rich in natural resources and endowed with a highly educated population,with its youth standing out as a particularly dynamic force. 展开更多
关键词 innovation DEVELOPMENT natural resources economic sanctions development youth obstacles western economic sanctionsmeasures DREAMS
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Emerging lessons on how participatory scenario planning can support sustainable land management and climate resilience
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作者 Pattrawut Pusingha Robert A.Marchant +1 位作者 Richard M.Friend Rui Han 《Geography and Sustainability》 2026年第1期15-30,共16页
Land degradation,coupled with climate change impacts,poses serious threats to global land health and human well-being.Participatory scenario planning(PSP)has become a key tool for exploring these interconnected challe... Land degradation,coupled with climate change impacts,poses serious threats to global land health and human well-being.Participatory scenario planning(PSP)has become a key tool for exploring these interconnected challenges;however,its progress and effectiveness remain underexplored.This study reviews 46 papers,using PRISMA guidelines,to investigate how PSP supports sustainable land management and climate resilience.We document how PSP applications have evolved from a biophysical focus to one addressing broader environmental,societal,and economic challenges.Disparities in how participants engage across PSP phases document the need for more equitable and meaningful participation.Clustering future scenarios reveals the complex interconnections among ecological,social,and economic factors underpinning land management and climate resilience,underscoring the need for inclusive and integrated strategies.From the emerging trends,we identify opportunities to advance PSP implementation,including early engagement of decision-makers,balanced representation and equitable power dynamics,meaningful participation,cross-disciplinary collaboration,integration of human-nature relationships,and regular revision of future pathways.Overall,our review highlights PSP’s potential to co-create inclusive,equitable scenarios and actionable pathways towards sustainable and resilient land use futures. 展开更多
关键词 Agriculture Food security Climate change Community engagement Sustainable development Development policy
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BUILDING BRIDGES CREATES JOBS FOR WOMEN
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作者 Wei Xuanyi 《Women of China》 2026年第3期64-66,共3页
The Outline of Women's Development in China(2021-2030)has proposed goals and supportive measures,to promote women's employment and entrepreneurship,and to guarantee equal rights and opportunities for women to ... The Outline of Women's Development in China(2021-2030)has proposed goals and supportive measures,to promote women's employment and entrepreneurship,and to guarantee equal rights and opportunities for women to participate in economic development.In the process of promoting high-quality economic development,China is upholding employment as a priority. 展开更多
关键词 economic developmentchina economic development job creation womens development economic developmentin EMPLOYMENT equal rights ENTREPRENEURSHIP
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Paths to Modernization
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作者 XIA YUANYUAN 《China Today》 2026年第1期42-44,共3页
Discussions on Chinese modernization are offering African countries both conceptual inspiration and practical references as they explore their own sustainable development paths.
关键词 chinese modernization conceptual inspiration sustainable development PATHS practical references MODERNIZATION sustainable development paths African countries
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