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A FORMAL REPRESENTATION FOR FEATURE-BASED DESIGN 被引量:1
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作者 孙正兴 丁秋林 张福炎 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1997年第1期37-46,共10页
Feature based design has been regarded as a promising approach for CAD/CAM integration.This paper aims to establish a domain independent representation formalism for feature based design in three aspects: formal re... Feature based design has been regarded as a promising approach for CAD/CAM integration.This paper aims to establish a domain independent representation formalism for feature based design in three aspects: formal representation,design process model and design algorithm.The implementing scheme and formal description of feature taxonomy,feature operator,feature model validation and feature transformation are given in the paper.The feature based design process model suited for either sequencial or concurrent engineering is proposed and its application to product structural design and process plan design is presented. Some general design algorithms for developing feature based design system are also addressed.The proposed scheme provides a formal methodology elementary for feature based design system development and operation in a structural way. 展开更多
关键词 CAD CAM product modelling design process feature based design representation formalism
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AN APPROACH TO FEATURE-BASED PARAMETRIC DESIGN FOR DIE AND MOULD
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作者 翟建军 陈文亮 +1 位作者 黄翔 陈普仁 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1995年第2期168-171,共4页
An approach to feature-based parametric design for die and mould is proposed in this paper.The assembly relationship and parts of the die and mould are described by feature.The dependent relationship of features is de... An approach to feature-based parametric design for die and mould is proposed in this paper.The assembly relationship and parts of the die and mould are described by feature.The dependent relationship of features is described by parent-child operator structure.The feature shape and location can be modified by design parameters.An expert system is used for deriving a geometry of the features which satisfies the given constraints.This approach provides a more natural and convenient method of representing a parametric model of the die and mould. 展开更多
关键词 FEATURES expert systems computer aided design parametric design parent-child operator
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Progress in MOF-based catalyst design and reaction mechanisms for CO_(2)hydrogenation to methanol
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作者 YU Zhifu JIANG Lei WU Mingbo 《燃料化学学报(中英文)》 北大核心 2026年第1期146-162,共17页
Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon... Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon neutrality goals.The hydrogenation of CO_(2)to methanol not only enables carbon sequestration and recycling,but also provides a route to produce high value-added fuels and basic chemical feedstocks,holding significant environmental and economic potential.However,this conversion process is thermodynamically and kinetically limited,and traditional catalyst systems(e.g.,Cu/ZnO/Al_(2)O_(3))exhibit inadequate activity,selectivity,and stability under mild conditions.Therefore,the development of novel high-performance catalysts with precisely tunable structures and functionalities is imperative.Metal-organic frameworks(MOFs),as crystalline porous materials with high surface area,tunable pore structures,and diverse metal-ligand compositions,have the great potential in CO_(2)hydrogenation catalysis.Their structural design flexibility allows for the construction of well-dispersed active sites,tailored electronic environments,and enhanced metal-support interactions.This review systematically summarizes the recent advances in MOF-based and MOF-derived catalysts for CO_(2)hydrogenation to methanol,focusing on four design strategies:(1)spatial confinement and in situ construction,(2)defect engineering and ion-exchange,(3)bimetallic synergy and hybrid structure design,and(4)MOF-derived nanomaterial synthesis.These approaches significantly improve CO_(2)conversion and methanol selectivity by optimizing metal dispersion,interfacial structures,and reaction pathways.The reaction mechanism is further explored by focusing on the three main reaction pathways:the formate pathway(HCOO*),the RWGS(Reverse Water Gas Shift reaction)+CO*hydrogenation pathway,and the trans-COOH pathway.In situ spectroscopic studies and density functional theory(DFT)calculations elucidate the formation and transformation of key intermediates,as well as the roles of active sites,metal-support interfaces,oxygen vacancies,and promoters.Additionally,representative catalytic performance data for MOFbased systems are compiled and compared,demonstrating their advantages over traditional catalysts in terms of CO_(2)conversion,methanol selectivity,and space-time yield.Future perspectives for MOF-based CO_(2)hydrogenation catalysts will prioritize two main directions:structural design and mechanistic understanding.The precise construction of active sites through multi-metallic synergy,defect engineering,and interfacial electronic modulation should be made to enhance catalyst selectivity and stability.In addition,advanced in situ characterization techniques combined with theoretical modeling are essential to unravel the detailed reaction mechanisms and intermediate behaviors,thereby guiding rational catalyst design.Moreover,to enable industrial application,challenges related to thermal/hydrothermal stability,catalyst recyclability,and cost-effective large-scale synthesis must be addressed.The development of green,scalable preparation methods and the integration of MOF catalysts into practical reaction systems(e.g.,flow reactors)will be crucial for bridging the gap between laboratory research and commercial deployment.Ultimately,multi-scale structure-performance optimization and catalytic system integration will be vital for accelerating the industrialization of MOF-based CO_(2)-to-methanol technologies. 展开更多
关键词 CO_(2)hydrogenation metal-organic frameworks(MOFs) catalyst design reaction mechanism METHANOL
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Advanced Design for High-Performance and AI Chips
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作者 Ying Cao Yuejiao Chen +2 位作者 Xi Fan Hong Fu Bingang Xu 《Nano-Micro Letters》 2026年第1期306-336,共31页
Recent years have witnessed transformative changes brought about by artificial intelligence(AI)techniques with billions of parameters for the realization of high accuracy,proposing high demand for the advanced and AI ... Recent years have witnessed transformative changes brought about by artificial intelligence(AI)techniques with billions of parameters for the realization of high accuracy,proposing high demand for the advanced and AI chip to solve these AI tasks efficiently and powerfully.Rapid progress has been made in the field of advanced chips recently,such as the development of photonic computing,the advancement of the quantum processors,the boost of the biomimetic chips,and so on.Designs tactics of the advanced chips can be conducted with elaborated consideration of materials,algorithms,models,architectures,and so on.Though a few reviews present the development of the chips from their unique aspects,reviews in the view of the latest design for advanced and AI chips are few.Here,the newest development is systematically reviewed in the field of advanced chips.First,background and mechanisms are summarized,and subsequently most important considerations for co-design of the software and hardware are illustrated.Next,strategies are summed up to obtain advanced and AI chips with high excellent performance by taking the important information processing steps into consideration,after which the design thought for the advanced chips in the future is proposed.Finally,some perspectives are put forward. 展开更多
关键词 Artificial intelligence Advanced chips AI chips design tactics Review and perspective
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Stability ofWorkpkce Setup in Feature-Based Fixture Planning System
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作者 ShenXiaohong LiuXuan 《Computer Aided Drafting,Design and Manufacturing》 2002年第2期37-43,共7页
Analyzed the issues of stability of workpiece during clamping and machining. Discussed classification of the stability problem according to the forces acting on the part in the commonly used machining processes; gave ... Analyzed the issues of stability of workpiece during clamping and machining. Discussed classification of the stability problem according to the forces acting on the part in the commonly used machining processes; gave the methods of calculating clamping force and measures to guarantee the stability of workpiece in the feature-based fixture planning design system. 展开更多
关键词 feature-based design fixture planning stability algorithm
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中学物理跨学科实践Design模型的建构与案例研究 被引量:1
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作者 张跃 崔琰 《中学物理》 2025年第10期14-17,共4页
基于中学物理跨学科实践视角,构建了跨学科实践设计模型(Design模型).该设计模型由发现问题(Discovery)、探究实践(Experiment)、问题解决(Solution)、迭代发展(Iteration)、目标导向(Goal)和作品生成(New)6个环节构成,聚焦学生的主体性... 基于中学物理跨学科实践视角,构建了跨学科实践设计模型(Design模型).该设计模型由发现问题(Discovery)、探究实践(Experiment)、问题解决(Solution)、迭代发展(Iteration)、目标导向(Goal)和作品生成(New)6个环节构成,聚焦学生的主体性,发展学生问题解决能力和创新能力.分析了模型的理论基础和内涵,并以跨学科实践案例展示了Design模型在促进学生主动学习、概念理解、问题解决和创新能力提升等方面的应用效果,为中学物理教师提供理论与实践相结合的教学策略参考. 展开更多
关键词 中学物理 design模型 跨学科实践 教学策略
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工艺美术语境下“图案(design)”观念的演变及影响
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作者 朱永明 《苏州科技大学学报(社会科学版)》 2025年第6期73-81,110,共10页
清末民初,在工程图画、实用工艺与美术教育的推进下,兼具应用性与观赏性的“图案(design)”观念被引入我国,并与中国设计传统深度融合,逐渐形成实用、装饰与形式审美的艺术设计定位,成为我国近现代工艺美术体系的核心价值。“图案(desi... 清末民初,在工程图画、实用工艺与美术教育的推进下,兼具应用性与观赏性的“图案(design)”观念被引入我国,并与中国设计传统深度融合,逐渐形成实用、装饰与形式审美的艺术设计定位,成为我国近现代工艺美术体系的核心价值。“图案(design)”观念不仅奠定了我国现代设计发展的基础,也形塑了近百年中国化设计实践的内在逻辑与路径。但由于自身发展中的局限,改革开放后又受到工业化市场、媒体传播发展的强劲冲击,未能适应信息化时代设计发展需求,“图案(design)”从曾经的“工艺(设计)之母”逐渐沉淀为具体专业领域的术语。其独特的发展历程、观念演变与时代际遇,对我国现代设计体系构建影响深远,也为我国当代设计的主体性建构和未来发展提供了宝贵经验与启示。 展开更多
关键词 “图案(design)” 工艺美术 图画 设计观念
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Feature-Based Aggregation and Deep Reinforcement Learning:A Survey and Some New Implementations 被引量:15
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作者 Dimitri P.Bertsekas 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2019年第1期1-31,共31页
In this paper we discuss policy iteration methods for approximate solution of a finite-state discounted Markov decision problem, with a focus on feature-based aggregation methods and their connection with deep reinfor... In this paper we discuss policy iteration methods for approximate solution of a finite-state discounted Markov decision problem, with a focus on feature-based aggregation methods and their connection with deep reinforcement learning schemes. We introduce features of the states of the original problem, and we formulate a smaller "aggregate" Markov decision problem, whose states relate to the features. We discuss properties and possible implementations of this type of aggregation, including a new approach to approximate policy iteration. In this approach the policy improvement operation combines feature-based aggregation with feature construction using deep neural networks or other calculations. We argue that the cost function of a policy may be approximated much more accurately by the nonlinear function of the features provided by aggregation, than by the linear function of the features provided by neural networkbased reinforcement learning, thereby potentially leading to more effective policy improvement. 展开更多
关键词 REINFORCEMENT learning dynamic programming Markovian DECISION problems AGGREGATION feature-based ARCHITECTURES policy ITERATION DEEP neural networks rollout algorithms
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A Feature-Based Parametric Product Modeling System in CIMS Environment 被引量:4
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作者 李海龙 《High Technology Letters》 EI CAS 1997年第1期13-16,共4页
This paper proposes an approach of developing the feature based parametric product modeling system which is suitable for integrated engineering design in CIMS environment.The architecture of ZD--MCADII and the charact... This paper proposes an approach of developing the feature based parametric product modeling system which is suitable for integrated engineering design in CIMS environment.The architecture of ZD--MCADII and the characteristics of its each module are introduced in detail. ZD--MCADII’s product data is managed by an object--oriented database management system OSCAR, and the product model is built according to the standard STEP. The product design is established on a unified product model, and all the product data are globally associated in ZD--MCADII. ZD--MCADII provides various design features to facilitate the product design, and supports the integrity of CAD, CAPP and CAM. 展开更多
关键词 CIMS FEATURE based modeling PARAMETRIC design PRODUCT model OODB
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STUDY ON AN OBJECT-ORIENTED FEATURE-BASED CAD OF HYDRAULIC MANIFOLD BLOCK 被引量:3
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《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2000年第3期206-211,共6页
关键词 CAD STUDY ON AN OBJECT-ORIENTED feature-based CAD OF HYDRAULIC MANIFOLD BLOCK ACIS
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Manufacturing feature-based cost estimation of cast parts
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作者 Muhammad Sajid Ahmad Wasim +1 位作者 Salman Hussain Mirza Jahanzaib 《China Foundry》 SCIE 2018年第6期464-469,共6页
Seventy percent of new product cost is committed in the design phase. Therefore, the cost needs to be minimized. Incorporating accurate cost estimation capabilities into manufacturing processes can help industries to ... Seventy percent of new product cost is committed in the design phase. Therefore, the cost needs to be minimized. Incorporating accurate cost estimation capabilities into manufacturing processes can help industries to minimize the cost and optimize the design. The casting process has been employed as a key process to manufacture parts having the advantage of low cost and customized products in foundry industry. This paper presents a cost estimation system for the casting process based on the design features, which incorporates the casting information at the design stage of castings. It aims to deliver the best cost-effective choice for casting design features of a product. Two kinds of knowledge, namely economical knowledge(describing the relation between the casting design considerations and the cost) and technical knowledge(involving the material of the casting features) were structured in this research work. On the basis of the minimum product cost, casting material selection can be carried out in detail. The developed system has been validated through an industrial case study. 展开更多
关键词 COST ESTIMATION model CASTING process design FEATURES
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Feature-based Image Sequence Compression Coding
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作者 周志权 Jia Shilou 《High Technology Letters》 EI CAS 2001年第2期31-33,共3页
A novel compressing method for video teleconference applications is presented. Semantic-based coding based on human image feature is realized, where human features are adopted as parameters. Model-based coding and the... A novel compressing method for video teleconference applications is presented. Semantic-based coding based on human image feature is realized, where human features are adopted as parameters. Model-based coding and the concept of vector coding are combined with the work on image feature extraction to obtain the result. 展开更多
关键词 Compression coding MODEL-BASED feature-based
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Design Guidelines for Composition of Brazing Filler Metals and Evolution Mechanisms of Typical Microstructures 被引量:6
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作者 Long Weimin 《稀有金属材料与工程》 北大核心 2025年第4期837-853,共17页
Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler ... Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler metals is ever-increasing.It is of great significance to investigate the optimized composition design methods and to establish systematic design guidelines for brazing filler metals.This study elucidated the fundamental rules for the composition design of brazing filler metals from a three-dimensional perspective encompassing the basic properties of applied brazing filler metals,formability and processability,and overall cost.The basic properties of brazing filler metals refer to their mechanical properties,physicochemical properties,electromagnetic properties,corrosion resistance,and the wettability and fluidity during brazing.The formability and processability of brazing filler metals include the processes of smelting and casting,extrusion,rolling,drawing and ring-making,as well as the processes of granulation,powder production,and the molding of amorphous and microcrystalline structures.The cost of brazing filler metals corresponds to the sum of materials value and manufacturing cost.Improving the comprehensive properties of brazing filler metals requires a comprehensive and systematic consideration of design indicators.Highlighting the unique characteristics of brazing filler metals should focus on relevant technical indicators.Binary or ternary eutectic structures can effectively enhance the flow spreading ability of brazing filler metals,and solid solution structures contribute to the formability.By employing the proposed design guidelines,typical Ag based,Cu based,Zn based brazing filler metals,and Sn based solders were designed and successfully applied in major scientific and engineering projects. 展开更多
关键词 design of brazing filler metals design guidelines for composition Ag based brazing filler metals eutectic structures evolution
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DIMENSION VARIATION OF FEATURE-BASED MODEL BY OPERATING DIRECTLY ON B-REP
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作者 何小朝 王宗彦 +1 位作者 彭维 张铁昌 《Chinese Journal of Aeronautics》 SCIE EI CSCD 1998年第2期57-63,共7页
DIMENSIONVARIATIONOFFEATURE┐BASEDMODELBYOPERATINGDIRECTLYONB┐REPHEXiaozhao(何小朝),WANGZongyan(王宗彦)PENGWei(彭维),... DIMENSIONVARIATIONOFFEATURE┐BASEDMODELBYOPERATINGDIRECTLYONB┐REPHEXiaozhao(何小朝),WANGZongyan(王宗彦)PENGWei(彭维),ZHANGTiechang(张铁昌... 展开更多
关键词 design by feature CONSTRAINT feature based model dimension variation
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Feature-based and objectoriented product information model for welding structure
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作者 林三宝 杨春利 +1 位作者 黎明 吴林 《China Welding》 EI CAS 1999年第2期3-10,共8页
Product information model for welding structure plays an important role for the integration of welding CAD/CAPP/CAM. However, existing CAD modeling systems are not capable of providing enough information for subsequen... Product information model for welding structure plays an important role for the integration of welding CAD/CAPP/CAM. However, existing CAD modeling systems are not capable of providing enough information for subsequent manufacturing activities such as CAPP and CAM. A new design approach using feature technique and object oriented programming method is put forward in this paper in order to create the product information model of welding structure. With this approach, the product information model is able to effectively support computer aided welding process planning, fixturing, assembling, path planning of welding robot and other manufacturing activities. The feature classification and representing scheme of welding structure are discussed. A prototype system is developed based on feature and object oriented programming. Its structure and functions are given in detail. 展开更多
关键词 object oriented programming feature based design product information model welding structure CAD/CAM integration
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基于Matlab App Designer的冲量等效原理仿真系统开发
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作者 霍永超 倪圆圆 +2 位作者 赵飞 俞张勇 张虎 《电气电子教学学报》 2025年第2期67-70,共4页
冲量等效原理是“电力电子技术”教学中的重要内容,但理论抽象、推导过程繁琐。通常,教学过程中往往侧重于定性分析,缺少定量计算和波形影响因素分析。利用Matlab App Designer标准组件多、交互性强的特点,开发了一款可视化仿真系统。... 冲量等效原理是“电力电子技术”教学中的重要内容,但理论抽象、推导过程繁琐。通常,教学过程中往往侧重于定性分析,缺少定量计算和波形影响因素分析。利用Matlab App Designer标准组件多、交互性强的特点,开发了一款可视化仿真系统。仿真系统包含了窄脉冲的类型、含惯性环节的系统类型和脉宽的影响分析等方面。实践结果表明,可视化教学有利于增强学生对理论的理解,培养学生主动探索和求证的能力。 展开更多
关键词 冲量等效原理 仿真系统 Matlab App designer
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澳大利亚教材Design and Technology的特色与启示
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作者 王振强 何善亮 《湖北教育》 2025年第7期84-87,共4页
随着经济一体化和全球化进程的不断推进,世界各国目前都认识到技术与工程教育对于提升综合国力的重要性。基础教育阶段虽不以直接培养各领域的工程师或设计师为目标,但关注学生技术与工程素养的提升,让他们像工程师或设计师一样思考和... 随着经济一体化和全球化进程的不断推进,世界各国目前都认识到技术与工程教育对于提升综合国力的重要性。基础教育阶段虽不以直接培养各领域的工程师或设计师为目标,但关注学生技术与工程素养的提升,让他们像工程师或设计师一样思考和解决问题,这不仅不能回避,而且是亟须直面的问题。《义务教育科学课程标准(2022年版)》的颁布为中小学技术与工程教育的落实指明了方向。 展开更多
关键词 澳大利亚教材 design and Technology
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Design Discussion of a Wireless Fire Alarm System Based on Data Fusion Technology 被引量:1
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作者 Qun Wu Jinyang Wu 《Journal of Electronic Research and Application》 2025年第2期58-64,共7页
This article explores the design of a wireless fire alarm system supported by advanced data fusion technology.It includes discussions on the basic design ideas of the wireless fire alarm system,hardware design analysi... This article explores the design of a wireless fire alarm system supported by advanced data fusion technology.It includes discussions on the basic design ideas of the wireless fire alarm system,hardware design analysis,software design analysis,and simulation analysis,all supported by data fusion technology.Hopefully,this analysis can provide some reference for the rational application of data fusion technology to meet the actual design and application requirements of the system. 展开更多
关键词 Data fusion technology Fire alarm system Wireless alarm Hardware design Software design
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Application of Modern Art in Urban Landscape Design 被引量:1
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作者 ZHUANG Zi-yi ABUDUGENI Abuduxukuer TANG Xian-gong 《Agricultural Science & Technology》 2025年第1期55-59,共5页
With the progress of urbanization,urban landscape design has garnered increasing attention.Urban landscape design can not only reflect the construction level of a city but also has the functions of beautifying the urb... With the progress of urbanization,urban landscape design has garnered increasing attention.Urban landscape design can not only reflect the construction level of a city but also has the functions of beautifying the urban environment and enhancing the city image.Modern art enriches the expression forms of urban landscape design,and its integration with urban landscape design can greatly improve the urban landscape.This article elaborated on the connotations of modern art and urban landscape design and analyzed the application of modern art in urban landscape design.The application of modern art can help to achieve the goal of urban landscape design to the maximum extent. 展开更多
关键词 Modern art Urban landscape design
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Parametric design for the valve seat of a high-temperature and high-pressure valve inside wind tunnels 被引量:1
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作者 Fengwei HOU Haifeng SHU +4 位作者 Binbin WU Chengliang YU Zhehui MA Wenqing LI Jinyuan QIAN 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第3期266-276,共11页
A high-temperature and high-pressure valve is the key equipment of a wind tunnel system;it controls the generation of high-temperature and high-pressure gas.To reduce the adverse impact of high-temperature and high-pr... A high-temperature and high-pressure valve is the key equipment of a wind tunnel system;it controls the generation of high-temperature and high-pressure gas.To reduce the adverse impact of high-temperature and high-pressure gas on the strength of the valve body,a cooling structure is set on the valve seat.This can significantly reduce the temperature of the valve body and valve seat.The effects of its structure on the cooling characteristics and stress of the valve seat are studied,and six main parameters that can completely describe the geometry of the cooling structure are proposed.The central composite design method is used to select sample points,and the multi-objective genetic algorithm(MOGA)method is used for optimal structural design.A modification method according to the main parameters for the valve seat is proposed.The results show that the cooling structure weakens the pressure-bearing capability of the valve seat.Among the six main parameters of the valve seat,the distance from the end face of the lower hole to the Z-axis and the distance from the axis of the lower hole to the origin of the coordinates have the most obvious effects on the average stress of the valve seat.An optimum design value is proposed.This work can provide a reference for the design of high-temperature and high-pressure valves. 展开更多
关键词 Control valve Valve seat OPTIMIZATION Parametric design
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