期刊文献+
共找到533,756篇文章
< 1 2 250 >
每页显示 20 50 100
Top-Down Design of 260k Color TFT-LCD One-Chip Driver ICs
1
作者 魏廷存 高武 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第4期706-712,共7页
A top-down design methodology is proposed for the design of TFT-LCD one-chip driver ICs,and a 260k color, 176RGB× 220-dot TFT-LCD one-chip driver IC is successfully developed with silicon verification. This IC is... A top-down design methodology is proposed for the design of TFT-LCD one-chip driver ICs,and a 260k color, 176RGB× 220-dot TFT-LCD one-chip driver IC is successfully developed with silicon verification. This IC is a typical mixed-signal VLSI and is implemented by a 0.18μm HV CMOS process. The static power dissipation is about 5mW for 260k color display mode,and the settling time of the output grayscale voltages within 0.2% error is less than 26μs. 展开更多
关键词 TFT-LCD driver IC top-down design driving circuit mixed-signal VLSI
在线阅读 下载PDF
支持Top-Down Design的内燃机参数化建模 被引量:5
2
作者 易际明 杨靖 张亮峰 《中国制造业信息化(学术版)》 2004年第3期100-102,共3页
以三维参数化特征造型软件Pro/Engineer为平台 ,结合SL1 1 2 6内燃机设计实例 ,介绍了基于参数化技术的自顶向下设计过程与实施方法 ,给出了自顶向下设计所涉及的关键技术 ,该设计思想和方法支持并行工程及协同设计。
关键词 内燃机 参数化建模 参数化设计 自顶向下设计 PRO/E CAD
在线阅读 下载PDF
利用Top-Down Design模块进行工装设计 被引量:1
3
作者 刘玉莹 韩祥凤 《漯河职业技术学院学报》 2009年第2期19-20,共2页
简述利用Pro/Engineer中Top-Down Design小型模块,进行组件设计以及在小型工装设计中的应用体会。
关键词 Top—Down design模块 工装设计 应用
在线阅读 下载PDF
Top-down Design and Modular Design在CA4GV发动机开发中的应用 被引量:3
4
作者 樊宏彪 《内燃机》 2011年第6期12-13,共2页
概括介绍了在Pro-E设计环境下Top-down Design(自顶向下设计)及Modular Design(模块化设计)两大技巧在CA4GV-E4发动机开发中的应用。
关键词 Top—down design MODULAR Desing 发动机设计规范 流程优化及管理
在线阅读 下载PDF
Pro/Engineer Top-down Design在复点机系列产品开发中的应用 被引量:1
5
作者 李长春 《机电工程技术》 2010年第5期82-85,共4页
论述了Pro/Engineer Top-down Design设计理念及Top-down Design的优点、原则、所用到的工具和设计过程。以复点机的设计开发过程为例,详尽论述了Top-down Design的具体实施过程,为应用Top-down Design在产品设计开发的具体实施,提供理... 论述了Pro/Engineer Top-down Design设计理念及Top-down Design的优点、原则、所用到的工具和设计过程。以复点机的设计开发过程为例,详尽论述了Top-down Design的具体实施过程,为应用Top-down Design在产品设计开发的具体实施,提供理论依据和过程指导。 展开更多
关键词 top-down design BOTTOM-UP design 产品开发
在线阅读 下载PDF
利用Top-Down Design模块进行工装设计
6
作者 侯劲松 王虹鹉 白书清 《航天制造技术》 2005年第6期45-46,共2页
简述了Pro/Engineer中Top-DownDesign模块,介绍了利用此模块进行组件建模设计以及在小型工装设计中的应用体会。
关键词 top-down design 建模 应用 工装设计
在线阅读 下载PDF
基于MATLAB App Designer的数字岩心建模软件设计与开发
7
作者 左艳彤 邢兰昌 +1 位作者 贾宁洪 刘宝 《计算机测量与控制》 2026年第1期235-243,共9页
为解决现有商用数字岩心建模软件功能可扩展性弱、成本高等问题,文章基于MATLAB App Designer工具开发了一款集成化的数字岩心建模软件,该软件包括图像处理、图像分析和孔隙网络提取等三大功能模块;图像处理模块集成了中值滤波、高斯滤... 为解决现有商用数字岩心建模软件功能可扩展性弱、成本高等问题,文章基于MATLAB App Designer工具开发了一款集成化的数字岩心建模软件,该软件包括图像处理、图像分析和孔隙网络提取等三大功能模块;图像处理模块集成了中值滤波、高斯滤波、SUSAN平滑、图像锐化及阈值分割等多种图像处理算法;图像分析模块采用多平面切片与序列叠加方法、借助三维交互技术实现了岩心结构的三维可视化、切面展示与旋转浏览;孔隙网络提取模块采用最大球法提取孔隙网络,从而获取配位数、孔隙半径、孔隙体积等关键结构参数,利用直方图对结构参数分布进行统计分析;利用典型岩心样本对所开发的软件进行功能测试,结果表明:该软件功能集成度高、界面友好、操作简便,能够有效提升图像质量、对岩心图像进行三维可视化展示以及准确提取三维岩心的孔隙网络结构特征;软件具备良好的可扩展性和二次开发潜力,为后续开发数字岩心电学、声学、核磁共振等响应的数值仿真模块提供了前提。 展开更多
关键词 数字岩心 MATLAB App designer 图像处理 图像分析 孔隙网络提取
在线阅读 下载PDF
基于OpenRoads Designer的桥梁下部结构设计应用研究
8
作者 李昊 胡霜 《四川建材》 2026年第1期115-119,共5页
为积极推动BIM技术在我国桥梁工程领域的发展和落地应用,研究将桥梁下部结构的参数化设计与快速建模作为切入点。以Bentley平台为基础,以中国公路桥梁设计规范为依据,对OpenRoads Designer软件进行二次开发。通过分析当前桥梁建模软件... 为积极推动BIM技术在我国桥梁工程领域的发展和落地应用,研究将桥梁下部结构的参数化设计与快速建模作为切入点。以Bentley平台为基础,以中国公路桥梁设计规范为依据,对OpenRoads Designer软件进行二次开发。通过分析当前桥梁建模软件的现状及不足,系统阐述二次开发技术路线、参数化设计理念以及下部结构批量化布置方法。结合实际工程案例验证表明,该二次开发成果显著提升桥梁下部结构建模效率与准确性,为桥梁工程BIM技术的持续深化应用提供实践参考。 展开更多
关键词 BIM OpenRoads designer 二次开发 桥梁下部结构 参数化设计
在线阅读 下载PDF
Interface management on high speed two:managing multiple complex interfaces in the design and construction of high speed railway infrastructure in the United Kingdom
9
作者 Hudson Taivo Hitesh Shantilal Mistry 《Railway Sciences》 2026年第1期1-28,共28页
Purpose-Interface management is the process of managing communications,responsibilities and coordination of project parties,phases or physical entities which are dependent on one another.Interface management is a cruc... Purpose-Interface management is the process of managing communications,responsibilities and coordination of project parties,phases or physical entities which are dependent on one another.Interface management is a crucial part of managing any construction project-but particularly important for high-speed railway projects that often have several contractual parties and stakeholders,very long project timelines and huge upfront cost overlays.This paper discusses how various project interfaces were managed during the design and construction of the civil engineering infrastructure for the High Speed Two(HS2)project in the United Kingdom.Design/methodology/approach-The paper uses the case study methodology.Key interfaces on the HS2 project are grouped into various categories and the paper discusses how they were managed within the Area North Integrated Project Team(IPT)of the HS2 project made up of contractor Balfour Beatty VINCI(BBV),the Mott MacDonald SYSTRA Design Joint Venture(DJV)and client HS2 Ltd.3 different case studies drawn from across the IPT are used,each of them highlighting different interfaces and how these interfaces were managed.Findings-The paper shows how innovative technical designs and modern methods of construction were used to address some of the unique and peculiar challenges of designing a brand-new railway in the United Kingdom.Addressing the contrasting and often competing requirements of different stakeholders,coupled with challenging physical constraints of the very limited land available for the project and the use of a rarely used Act of Parliament in the delivery of the project required different approach to interface management.Collaboration and proactive stakeholder engagement are necessary for successful interface management on megaprojects.The authors posit that adopting an integrated approach to engineering and construction management is an essential ingredient for the successful delivery of high-speed railway projects.Originality/value-With many high-speed railway projects around the world coming up in the next few years,understanding the context and challenges for each country will help engineering and design managers adopt appropriate approaches for their projects.The lessons learned on the HS2 project are also transferable to other mega infrastructure projects with complex project interfaces. 展开更多
关键词 Interface management design management design constraints Project management
在线阅读 下载PDF
开级配排水路面Top-Down裂缝的预测探究
10
作者 欧阳天水 徐志祥 卜胤 《中国公路》 2026年第1期105-107,共3页
开级配排水路面的主要疲劳损坏形式为Top-Down裂缝。本研究旨在建立一种实用可靠的预测模型,用于分析该类路面Top-Down裂缝的发展规律及其关键影响因素,并结合实体工程案例验证模型精度。结果表明,该模型能够针对不同交通条件下的开级... 开级配排水路面的主要疲劳损坏形式为Top-Down裂缝。本研究旨在建立一种实用可靠的预测模型,用于分析该类路面Top-Down裂缝的发展规律及其关键影响因素,并结合实体工程案例验证模型精度。结果表明,该模型能够针对不同交通条件下的开级配排水路面,预测Top-Down裂缝的最可能发生时间及相应裂缝深度。 展开更多
关键词 top-down裂缝 开级配排水路面 预测模型
在线阅读 下载PDF
基于Top-Down三维协同的智轨电车开发技术
11
作者 张楷源 张陈林 +1 位作者 杨勇 李扬戈 《技术与市场》 2026年第1期64-68,73,共6页
智能轨道快运系统属于新型轨道交通制式,其核心智轨电车为复杂机电系统,设计难度大、周期长。开发了基于智轨电车特性的Top-Down设计方法,搭建了三维协同设计平台建设方案,并以某车型为对象开展实践应用。结果表明:Top-Down三维协同设... 智能轨道快运系统属于新型轨道交通制式,其核心智轨电车为复杂机电系统,设计难度大、周期长。开发了基于智轨电车特性的Top-Down设计方法,搭建了三维协同设计平台建设方案,并以某车型为对象开展实践应用。结果表明:Top-Down三维协同设计可有效克服传统设计模式干涉错误多、重量评估难、物料数量统计不准确的难点,有效提升设计效率及设计质量。 展开更多
关键词 智轨电车 自顶向下(top-down) 三维协同
在线阅读 下载PDF
Progress in MOF-based catalyst design and reaction mechanisms for CO_(2)hydrogenation to methanol
12
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
在线阅读 下载PDF
Inverse design framework of hybrid honeycomb structure with high impact resistance based on active learning
13
作者 Xingyu Shen Ke Yan +5 位作者 Difeng Zhu Hao Wu Shijun Luo Shaobo Qi Mengqi Yuan Xinming Qian 《Defence Technology(防务技术)》 2026年第1期407-421,共15页
In this study,an inverse design framework was established to find lightweight honeycomb structures(HCSs)with high impact resistance.The hybrid HCS,composed of re-entrant(RE)and elliptical annular re-entrant(EARE)honey... In this study,an inverse design framework was established to find lightweight honeycomb structures(HCSs)with high impact resistance.The hybrid HCS,composed of re-entrant(RE)and elliptical annular re-entrant(EARE)honeycomb cells,was created by constructing arrangement matrices to achieve structural lightweight.The machine learning(ML)framework consisted of a neural network(NN)forward regression model for predicting impact resistance and a multi-objective optimization algorithm for generating high-performance designs.The surrogate of the local design space was initially realized by establishing the NN in the small sample dataset,and the active learning strategy was used to continuously extended the local optimal design until the model converged in the global space.The results indicated that the active learning strategy significantly improved the inference capability of the NN model in unknown design domains.By guiding the iteration direction of the optimization algorithm,lightweight designs with high impact resistance were identified.The energy absorption capacity of the optimal design reached 94.98%of the EARE honeycomb,while the initial peak stress and mass decreased by 28.85%and 19.91%,respectively.Furthermore,Shapley Additive Explanations(SHAP)for global explanation of the NN indicated a strong correlation between the arrangement mode of HCS and its impact resistance.By reducing the stiffness of the cells at the top boundary of the structure,the initial impact damage sustained by the structure can be significantly improved.Overall,this study proposed a general lightweight design method for array structures under impact loads,which is beneficial for the widespread application of honeycomb-based protective structures. 展开更多
关键词 Re-entrant honeycomb Hybrid structures Inverse design Impact resistance LIGHTWEIGHT
在线阅读 下载PDF
The surface binding and energy issues in the rational design of separators for Li||S batteries
14
作者 Hongfang Du Lijing Wang +8 位作者 Shuyu Cheng Chao Wu Sheng Yang Yang Liu Yi Zhao Dandan Cui Shaowei Zhang Shixue Dou Liangxu Lin 《Journal of Energy Chemistry》 2026年第1期987-1013,I0021,共28页
Lithium-sulfur batteries(LSBs)represent a next-generation energy storage technology,but widespread applications are restricted by the shuttle of lithium polysulfides(LiPSs).The rational design of separators has been d... Lithium-sulfur batteries(LSBs)represent a next-generation energy storage technology,but widespread applications are restricted by the shuttle of lithium polysulfides(LiPSs).The rational design of separators has been demonstrated to be one of the most efficient and cost-effective strategies to curb the shuttle effect,and tremendous research progress has been achieved.The efficiency of a separator depends on its interaction with LiPSs,which is governed by the surface energy and binding strength.Despite several review works that have been reported to advance the separators,most of them primarily focus on active material innovation and construction.The most crucial issues of surface binding energy have not been systematically reviewed,limiting the precise design of efficient separators.In this review,fundamentals related to surface energy and binding interactions with LiPSs are comprehensively analyzed and discussed.With surface binding and energy main lines,the advancements in separator engineering strategies are elaborately summarized and discussed.Moreover,techniques for evaluating affinity to LiPSs are thoroughly analyzed to avoid any ambiguities in measurement.Based on the research context,valuable research directions are suggested to construct efficient separators.This work provides guidelines to regulate the surface binding and energy of separators for high-performance LSBs. 展开更多
关键词 Lithium-sulfur batteries SEPARATOR Surface binding affinity Surface energy Rational design
在线阅读 下载PDF
AI-assisted design of 3 D-printed prosthesis for integrated replacement of the hip,femur,and knee caused by osseous hydatidosis
15
作者 Yanlong Han Haoyuan Lei +7 位作者 Ruozhen Jia Wei Zhao Habaxi Kaken Deli Wang Yongsheng Liu Zhen Tan Li Wang Changchun Zhou 《Bio-Design and Manufacturing》 2026年第1期94-99,I0017,共7页
Cases of widespread bone hydatid infection are relatively rare in clinical practice.In this study,we reported for the first time a validated integrated repair therapy for multiple bone tissues,including the hip,femur,... Cases of widespread bone hydatid infection are relatively rare in clinical practice.In this study,we reported for the first time a validated integrated repair therapy for multiple bone tissues,including the hip,femur,and knee,caused by echinococ cosis.Artificial intelligence(AI)was used to develop a targeted surgical plan and to design a personalized prosthesis.Finite element analysis(FEA)was used to optimize the mechanical effectiveness of a customized integrated replacement prosthesis and to model stress distribution in the surrounding bone.Three-dimensional(3 D)printing was used to fabricate a customized prosthesis.With the assistance of AI,FEA,and 3 D printing technology,a personalized surgical plan and customized prosthesis were successfully constructed based on the patient’s disease.This approach achieved a successful therapeutic effect,demonstrating that AI-assisted personalized medicine holds great promise for the future. 展开更多
关键词 develop targeted surgical plan optimize mechanical effectiveness AI assisted design D printed prosthesis design personalized prosthesisfinite element analysis fea bone tissuesincluding bone hydatid infection integrated repair therapy
暂未订购
Optical design of wide-field and broadband light field camera for high-precision optical surface defect detection
16
作者 Chengchen Zhou Yukun Wang +7 位作者 Yue Ding Dacheng Wang Jiucheng Nie Jialong Li Zhixi Li Zheng Zhou Shuangshuang Zhang Xiaokun Wang 《Astronomical Techniques and Instruments》 2026年第1期64-74,共11页
To address the challenges of high-precision optical surface defect detection,we propose a novel design for a wide-field and broadband light field camera in this work.The proposed system can achieve a 50°field of ... To address the challenges of high-precision optical surface defect detection,we propose a novel design for a wide-field and broadband light field camera in this work.The proposed system can achieve a 50°field of view and operates at both visible and near-infrared wavelengths.Using the principles of light field imaging,the proposed design enables 3D reconstruction of optical surfaces,thus enabling vertical surface height measurements with enhanced accuracy.Using Zemax-based simulations,we evaluate the system’s modulation transfer function,its optical aberrations,and its tolerance to shape variations through Zernike coefficient adjustments.The results demonstrate that this camera can achieve the required spatial resolution while also maintaining high imaging quality and thus offers a promising solution for advanced optical surface defect inspection. 展开更多
关键词 Optical design Defect detection Wide-field camera Broadband light field camera
在线阅读 下载PDF
Integrating Carbonation Durability and Cover Scaling into Low-Carbon Concrete Design:A New Framework for Sustainable Slag-Based Mixtures
17
作者 Kang-Jia Wang Hongzhi Zhang +2 位作者 Runsheng Lin Jiabin Li Xiao-Yong Wang 《Computer Modeling in Engineering & Sciences》 2026年第1期416-435,共20页
Conventional low-carbon concrete design approaches have often overlooked carbonation durability and the progressive loss of cover caused by surface scaling,both of which can increase the long-term risk of reinforcemen... Conventional low-carbon concrete design approaches have often overlooked carbonation durability and the progressive loss of cover caused by surface scaling,both of which can increase the long-term risk of reinforcement corrosion.To address these limitations,this study proposes an improved design framework for low-carbon slag concrete that simultaneously incorporates carbonation durability and cover scaling effects into the mix proportioning process.Based on experimental data,a linear predictive model was developed to estimate the 28-day compressive strength of slag concrete,achieving a correlation coefficient of R=0.87711 and a root mean square error(RMSE)of 7.55 MPa.The mechanism-based equation exhibits strong physical interpretability,as each parameter corresponds to a clear physical process,satisfying the requirements of design codes for physical significance.By integrating the strength and carbon-emission models,the carbon-emission efficiency was further analyzed.Across all water–binder ratios(0.3,0.4,0.5),CO_(2) emissions per unit strength decreased steadily with increasing slag content,indicating that carbon efficiency is primarily governed by slag replacement rather than the water/binder ratio.Four design cases,all with a design strength of 30 MPa,were then evaluated to illustrate the combined effects of carbonation and scaling.In Case 1,without considering carbonation durability,the carbonation depth after 50 years exceeded the 25 mm cover,leading to potential corrosion.In Case 2,when carbonation durability was considered,the required actual strength increased to 31.28 MPa.When mild cover scaling of 3 mm was introduced(Case 3),the required strength rose to 34.59 MPa,and under severe scaling of 10 mm(Case 4),it increased to 45.73 MPa.These results indicate that intensified scaling demands higher strength and lower water/binder ratios to maintain durability.Overall,the proposed framework quantitatively balances strength,durability,and embodied carbon,supporting sustainable low-carbon concrete design. 展开更多
关键词 Low-CO_(2)concrete SLAG CARBONATION cover scaling optimal design
在线阅读 下载PDF
Advanced Design for High-Performance and AI Chips
18
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
在线阅读 下载PDF
Automatic gating and riser system design and defect control for K4169 superalloy guide blade casting based on parametric 3D modeling-simulation integrated system
19
作者 Le-chuan Li Ya-jun Yin +4 位作者 Bing-zheng Fan Guo-yan Shui Xiao-yuan Ji Jian-xin Zhou Lei Jin 《China Foundry》 2026年第1期20-30,共11页
Automation and intelligence have become the primary trends in the design of investment casting processes.However,the design of gating and riser systems still lacks precise quantitative evaluation criteria.Numerical si... Automation and intelligence have become the primary trends in the design of investment casting processes.However,the design of gating and riser systems still lacks precise quantitative evaluation criteria.Numerical simulation plays a significant role in quantitatively evaluating current processes and making targeted improvements,but its limitations lie in the inability to dynamically reflect the formation outcomes of castings under varying process conditions,making real-time adjustments to gating and riser designs challenging.In this study,an automated design model for gating and riser systems based on integrated parametric 3D modeling-simulation framework is proposed,which enhances the flexibility and usability of evaluating the casting process by simulation.Firstly,geometric feature extraction technology is employed to obtain the geometric information of the target casting.Based on this information,an automated design framework for gating and riser systems is established,incorporating multiple structural parameters for real-time process control.Subsequently,the simulation results for various structural parameters are analyzed,and the influence of these parameters on casting formation is thoroughly investigated.Finally,the optimal design scheme is generated and validated through experimental verification.Simulation analysis and experimental results show that using a larger gate neck(24 mm in side length) and external risers promotes a more uniform temperature distribution and a more stable flow state,effectively eliminating shrinkage cavities and enhancing process yield by 15%. 展开更多
关键词 numerical simulation automatic design investment casting parametric 3D modeling gating and riser system
在线阅读 下载PDF
Conceptual design of the subcritical assemblies based on the PWR conventional fuel using DRAGON and DONJON codes
20
作者 S.Abedi S.Z.Kalantari +2 位作者 J.Mokhtari M.H.Choopan Dastjerdi A.Asgari 《Nuclear Science and Techniques》 2026年第1期283-296,共14页
Subcritical reactors(SCRs)or subcritical assemblies(SCAs)are the main infrastructure for designing power reactors.These reactors are widely used for training and research because of their high level of inherent safety... Subcritical reactors(SCRs)or subcritical assemblies(SCAs)are the main infrastructure for designing power reactors.These reactors are widely used for training and research because of their high level of inherent safety.The objective of this study is to design a subcritical reactor using a pressurized water reactor(PWR)conventional fuel following two safety points.In the first approach,deeply placed SCR cores with an infinite multiplication factor(k_(∞))of less than unity were identified using the DRAGON lattice code.In the second approach,subcritical reactor cores with an effective multiplication factor(k_(eff))of less than unity were determined by coupling the cell calculations of the DRAGON lattice code and core calculations of the DONJON code.For the deeply subcritical reactor design,it was found that the reactor would remain inherently subcritical while using fuel rods with ^(235)U enrichment of up to 0.9%,regardless of the pitch of the fuel rods.In the second approach,the optimal pitches(1.3 to 2.3 cm)were determined for different fuel enrichment values from 1 to 5%.Subsequently,the k_(eff) was obtained for a fuel rod arrangement of 8×8 to 80×80,and the states in which the reactor would be subcritical were determined for different fuel enrichments at the corresponding optimal pitch.To validate the models used in the DRAGON and DONJON codes,the k_(eff) of the Isfahan Light Water Subcritical Reactor(LWSCR)was experimentally measured and compared with the results of the calculations.Finally,the effects of fuel and moderator temperature changes were investigated to ensure that the designed assemblies remained in the subcritical state at all operational temperatures. 展开更多
关键词 Subcritical reactor design Multiplication factor Light water subcritical reactor(LWSCR) Moderator temperature coefficient(MTC) Fuel temperature coefficient(FTC)
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部