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Dynamic Event-Triggered Consensus Control for Input Constrained Multi-Agent Systems With a Designable Minimum Inter-Event Time
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作者 Meilin Li Yue Long +2 位作者 Tieshan Li Hongjing Liang C.L.Philip Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第3期649-660,共12页
This paper investigates the consensus control of multi-agent systems(MASs) with constrained input using the dynamic event-triggered mechanism(ETM).Consider the MASs with small-scale networks where a centralized dynami... This paper investigates the consensus control of multi-agent systems(MASs) with constrained input using the dynamic event-triggered mechanism(ETM).Consider the MASs with small-scale networks where a centralized dynamic ETM with global information of the MASs is first designed.Then,a distributed dynamic ETM which only uses local information is developed for the MASs with large-scale networks.It is shown that the semi-global consensus of the MASs can be achieved by the designed bounded control protocol where the Zeno phenomenon is eliminated by a designable minimum inter-event time.In addition,it is easier to find a trade-off between the convergence rate and the minimum inter-event time by an adjustable parameter.Furthermore,the results are extended to regional consensus of the MASs with the bounded control protocol.Numerical simulations show the effectiveness of the proposed approach. 展开更多
关键词 Constrained input designable minimum inter-event time directed communication topology dynamic event-triggered mechanism MASs consensus control
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FIXED-DESIGN SEMIPARAMETRIC REGRESSION FOR LINEAR TIME SERIES 被引量:8
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作者 胡舒合 《Acta Mathematica Scientia》 SCIE CSCD 2006年第1期74-82,共9页
This article studies parametric component and nonparametric component estimators in a semiparametric regression model with linear time series errors; their r-th mean consistency and complete consistency are obtained u... This article studies parametric component and nonparametric component estimators in a semiparametric regression model with linear time series errors; their r-th mean consistency and complete consistency are obtained under suitable conditions. Finally, the author shows that the usual weight functions based on nearest neighbor methods satisfy the designed assumptions imposed. 展开更多
关键词 Fixed-design semiparametric regression linear time series
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Settling Time Design and Parameter Tuning Methods for Finite-Time P-PI Control 被引量:1
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作者 Keigo Hiruma Hisakazu Nakamura Yasuyuki Satoh 《Journal of Control Science and Engineering》 2016年第1期1-10,共10页
High precision position control and high speed control of the robot manipulators are fundamental and important control problems. The effectiveness of finite-time P-PI control was confirmed by end-effector position con... High precision position control and high speed control of the robot manipulators are fundamental and important control problems. The effectiveness of finite-time P-PI control was confirmed by end-effector position control of robot manipulators. However, parameter tuning method has not been proposed to finite-time P-PI control. In this paper, we propose a settling time design method and a parameter tuning method for the finite-time P-PI control. The effectiveness of the proposed parameter tuning method is confirmed by experiments of end-effcctor position control of a robot manipulator. 展开更多
关键词 Nonlinear control finite-time control P-PI control settling time design robot manipulator.
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Expression of Time Dimension in Landscape Design
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作者 LUO Feng LIU Xiaohui 《Journal of Landscape Research》 2013年第4期41-42,46,共3页
"Landscape is an expression symbol with the time dimension influenced by historical process. Time not only influences landscape project and changing process of regional materials all the time, but also shapes for... "Landscape is an expression symbol with the time dimension influenced by historical process. Time not only influences landscape project and changing process of regional materials all the time, but also shapes forms and cultural connotations of landscape. Proceeding from basic concepts of time dimension in landscape design, influence and significance of time in landscape design were explored from the perspectives of presentation (material changes), perception (spatial experience) and culture (historical process) of time dimension. 展开更多
关键词 LANDSCAPE design time DIMENSION SPACE CULTURE
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A Pilot Study on the Service Design in Taipei Cloud Based on Time-Geography
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作者 Jui-Ping Ma Rungtai Lin 《通讯和计算机(中英文版)》 2014年第7期552-558,共7页
关键词 时间地理学 服务质量 台北市 设计 WEB服务 WI-FI 智能手机 空间因素
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Design and simulation of time-of-flight neutron reflectometer 被引量:2
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作者 LI Xinxi WANG Yan HUANG Chaoqiang CHEN Bo 《Nuclear Science and Techniques》 SCIE CAS CSCD 2010年第3期157-160,共4页
In this paper,a time of flight neutron reflectometer model is proposed.According to the original objective inputting physical parameters and expectations,computer simulation was done by McStas package.With the open sl... In this paper,a time of flight neutron reflectometer model is proposed.According to the original objective inputting physical parameters and expectations,computer simulation was done by McStas package.With the open slit, neutron flux at sample position was about 1×10~5 n·cm^(-2)·S^(-1),and the optimal resolution could reach 0.5%.The results show that the model has a good performance.The design of this model can be an instruction for neutron reflectometer construction or project analysis in the future. 展开更多
关键词 反射模型 中子通量 飞行时间 设计 仿真 计算机模拟 最佳分辨率 物理参数
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FIXED-DESIGN REGRESSION FOR LINEARTIME SERIES 被引量:5
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作者 胡舒合 朱春华 +1 位作者 程业斌 王立春 《Acta Mathematica Scientia》 SCIE CSCD 2002年第1期9-18,共10页
This paper obtains asymptotic normality for double array sum of linear time series zeta(t), and gives its application in the regression model. This generalizes the main results in [1].
关键词 linear time series asymptotic normality fixed design martingale difference
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Study the effect of formulation variables in the development of timed-release press-coated tablets by Taguchi design
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作者 Chikkanna Narendra Mayasandra SrinavasaIyengar Srinath 《Natural Science》 2010年第4期379-387,共9页
In this investigation, the effect of formulation variables on the release properties of timed- release press-coated tablets was studied using the Taguchi method of experimental design. Formulations were prepared based... In this investigation, the effect of formulation variables on the release properties of timed- release press-coated tablets was studied using the Taguchi method of experimental design. Formulations were prepared based on Taguchi orthogonal array design with different types of hydrophilic polymers (X1), varying hydrophilic polymer/ethyl cellulose ratio (X2), and addition of magnesium stearate (X3) as independent variables. The design was quantitatively evalu-ated by best fit mathematical model. The results from the statistical analysis revealed that factor X1, X3 and interaction factors between X1X2 and X1X3 were found to be significant on the re-sponse lag time (Y1), where as only factor X1 was found to be significant on the response percent drug release at 8 hrs (Y2). A numerical optimization technique by desirability function was used to optimize the response variables, each having a different target. Based on the re-sults of optimization study, HPC was identified as the most suitable hydrophilic polymer and incorporation of hydrophobic agent magnesium stearate, could significantly improve the lag time of the timed-release press-coated tablet. 展开更多
关键词 Press-Coated TABLET Taguchi design HYDROPHILIC Polymers timed-Release Hydrophobic Agents
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A Comparison of Within-Subjects and Between-Subjects Designs in Studies with Discrete-Time Survival Outcomes
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作者 Maryam Safarkhani Mirjam Moerbeek 《Open Journal of Statistics》 2017年第2期305-322,共18页
Crossover designs are well-known to have major advantages when comparing the effects of various non-curative treatments. We compare efficiencies of several crossover designs along with the Balaam’s design with that o... Crossover designs are well-known to have major advantages when comparing the effects of various non-curative treatments. We compare efficiencies of several crossover designs along with the Balaam’s design with that of a parallel group design pertaining to longitudinal studies where event time can only be measured in discrete time intervals. With equally sized sequences, the parallel group design results in the greater efficiency if the number of time periods is small. However, the crossover and Balaam’s designs tend to be more efficient as the study duration increases. The degree to which these designs add efficiency depends on the baseline hazard function and effect size. Additionally, we incorporate different cost considerations at the subject level when comparing the designs to determine the most cost-efficient design. Researchers might consider the crossover or Balaam’s design more efficient if the duration of the study is long enough, especially if the costs of applying the baseline treatment are higher. 展开更多
关键词 Balaam’s design CROSSOVER design COST-EFFICIENCY DISCRETE-time Survival ENDPOINT Efficiency Measure Parallel Group design
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A Real-time Concurrent Product and Process Design System for Mechanical Parts
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作者 宋玉银 《High Technology Letters》 EI CAS 1999年第1期75-81,共7页
A real time concurrent product and process design system for mechanical parts is described in this paper. It consists of integrated product model, the expert system of product manufacturability evaluation and the con... A real time concurrent product and process design system for mechanical parts is described in this paper. It consists of integrated product model, the expert system of product manufacturability evaluation and the controller of concurrent design. With the help of the controller of concurrent design, each feature of a part can be designed and evaluated based on manufacturing knowledge and resources, and can be modified according to the results of evaluation. The machining method of design feature can be selected based on manufacturing knowledge. So real time concurrent product and process design can be implemented based on integrated product model that is established based on generalized feature. Products and its design process can be optimized with the help of this system. The information and function integration of product design process can be realized. The time to market and the cost of products can be reduced. 展开更多
关键词 CONCURRENT Engineering Real time CONCURRENT design Integrated PRODUCT model EXPERT SYSTEM
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Design and Analysis of Test Schemes of Static Postponing Time on Shrapnels Used to Riot Control
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作者 单永海 闵碧波 孙国基 《Defence Technology(防务技术)》 SCIE EI CAS 2006年第2期102-105,共4页
The test scheme of static postponing time given in our actual national military test standard on shrapnels used to control riot is a nine-point test scheme on the combined action of three kinds of temperatures and thr... The test scheme of static postponing time given in our actual national military test standard on shrapnels used to control riot is a nine-point test scheme on the combined action of three kinds of temperatures and three kinds of pressures, the consumed ammunitions are more excessive. Statistic analysis and tentative checkout about a lot of test data are done, feasibility gists are put forward for optimizing of the test design scheme. The optimizing design and data analysis of test scheme of the item are done by managing uniformity design theory, two scientific and reasonable six-point test schemes are confirmed. The feasibility and reliability of the optimizing design schemes put forward above are proved ulteriorly by test validating. The gained schemes not only have good design uniformity and little ammunition wastage and meet the test demand, but also have better forecast ability for the result data of other points using the mathematic models from the actual test points. 展开更多
关键词 防暴动榴弹 延时 测试计划 静态定位
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Real-time Parallel Processing System Design and Implementation for Underwater Acoustic Communication Based on Multiple Processors
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作者 阎振华 黄建国 +1 位作者 张群飞 何成兵 《Defence Technology(防务技术)》 SCIE EI CAS 2007年第2期139-144,共6页
ADSP-TS101 is a high performance DSP with good properties of parallel processing and high speed.According to the real-time processing requirements of underwater acoustic communication algorithms,a real-time parallel p... ADSP-TS101 is a high performance DSP with good properties of parallel processing and high speed.According to the real-time processing requirements of underwater acoustic communication algorithms,a real-time parallel processing system with multi-channel synchronous sample,which is composed of multiple ADSP-TS101s,is designed and carried out.For the hardware design,field programmable gate array(FPGA)logical control is adopted for the design of multi-channel synchronous sample module and cluster/data flow associated pin connection mode is adopted for multiprocessing parallel processing configuration respectively.And the software is optimized by two kinds of communication ways:broadcast writing way through shared bus and point-to-point way through link ports.Through the whole system installation,connective debugging,and experiments in a lake,the results show that the real-time parallel processing system has good stability and real-time processing capability and meets the technical design requirements of real-time processing. 展开更多
关键词 信息处理 结构 设计最佳化 电子
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A Decision Support Framework for the Choice of Languages and Methods for the Design of Real Time Embedded Systems
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作者 Valéry M. Monthe Laurent Nana +1 位作者 Georges E. Kouamou Claude Tangha 《Journal of Software Engineering and Applications》 2016年第7期353-397,共45页
The choice of methods or design languages is a crucial phase in the development of systems and software, also for real time and embedded systems. An open question that remains in the design of these types of systems i... The choice of methods or design languages is a crucial phase in the development of systems and software, also for real time and embedded systems. An open question that remains in the design of these types of systems is to build a method, or to choose one among those existing, capable to cover the life cycle of a project, and particularly the development phases. This article contributes to answer the question, by proposing an approach based on a multi-criteria comparative study, of few languages and methods dedicated to the design of real time and embedded systems. The underlying objective of this work is to present to designers a wide range of approaches, and elements that can guide their choices. In order to reach this goal, we propose different comparison criteria. Each criterion is divided into sub-criteria, so that the designers can refine their choices according to the qualities they prefer and wish to have in the method or language. We also define a rating scale which is used to assess the retained languages and methods. The scores obtained from this assessment are presented in tables, one table per criterion, followed by a summary table giving the overall scores. Graphics built from these tables are provided and intend to facilitate the judgement and thus the choice of the designers. 展开更多
关键词 design Method Modelling Language Real-time System Embedded System Comparison Criteria
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基于作者网络结构特征的学术虚拟社区知识交流效率评价
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作者 李树青 郑天生 《科技情报研究》 2024年第1期33-48,共16页
[目的/意义]学术虚拟社区知识交流效率测度对于了解和改进学术虚拟社区本身有着积极的意义,也为相关知识交流效率评价方法提供了新的分析应用领域。[方法/过程]文章提出了一种利用博文作者网络进行学术虚拟社区知识交流效率测度的方法... [目的/意义]学术虚拟社区知识交流效率测度对于了解和改进学术虚拟社区本身有着积极的意义,也为相关知识交流效率评价方法提供了新的分析应用领域。[方法/过程]文章提出了一种利用博文作者网络进行学术虚拟社区知识交流效率测度的方法。通过汇总每位博文作者的浏览总量、推荐总数、评论总数、文章类别数量等特征设计了网络节点权值,并根据博文作者领域特征进行边权值设计。然后对该网络从路径长度、聚类系数等角度,分别按照学科版块和博文类别版块,结合时序演化特征,分析了相关版块中知识交流的效果和效率,并对相关现象和结论做了必要的总结。[结果/结论]对学术虚拟社区知识交流相关研究进行了较为完整的前期研究总结,并对需要关注的研究方向和内容作出了阐述和介绍。 展开更多
关键词 学术虚拟社区 效率评价 网络分析 权值设计 时序分析
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国家知识产权战略对高技术产业创新效率的影响——基于时间断点回归设计
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作者 周衍平 戚周洁 陈会英 《山东科技大学学报(社会科学版)》 2024年第2期79-89,共11页
在我国从知识产权大国向知识产权强国迈进的关键时期,探究实行国家知识产权战略对高技术产业创新效率的影响,既是推动高技术产业升级的有效手段,也是改革完善知识产权保护与管理制度的内在需求。基于2000—2019年中国28个省市地区高技... 在我国从知识产权大国向知识产权强国迈进的关键时期,探究实行国家知识产权战略对高技术产业创新效率的影响,既是推动高技术产业升级的有效手段,也是改革完善知识产权保护与管理制度的内在需求。基于2000—2019年中国28个省市地区高技术产业创新数据,运用时间断点回归方法检验中国实施国家知识产权战略对高技术产业创新效率的影响。研究表明:国家知识产权战略的实施在整体上显著促进高技术产业创新效率提升。区域异质性分析发现,战略实施显著提升了东、西部地区高技术产业的创新效率,但对中部地区创新效率的提升作用不显著。研究结论为优化知识产权政策设计、提高高技术产业的创新能力提供了经验证据。未来应进一步健全知识产权制度体系,并结合区域差异因地制宜制定知识产权政策。 展开更多
关键词 知识产权战略 高技术产业 创新效率 时间断点回归
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Performance of Cross-Layer Design with Power Allocation in Space-Time Coded MIMO Systems
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作者 杨定礼 刘岩 虞湘宾 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2014年第4期431-439,共9页
A cross-layer design(CLD)scheme with combination of power allocation,adaptive modulation(AM)and automatic repeat request(ARQ)is presented for space-time coded MIMO system under imperfect feedback,and the corresponding... A cross-layer design(CLD)scheme with combination of power allocation,adaptive modulation(AM)and automatic repeat request(ARQ)is presented for space-time coded MIMO system under imperfect feedback,and the corresponding system performance is investigated in a Rayleigh fading channel.Based on imperfect feedback information,a suboptimal power allocation(PA)scheme is derived to maximize the average spectral efficiency(SE)of the system.The scheme is based on a so-called compressed SNR criterion,and has a closed-form expression for positive power allocation,thus being computationally efficient.Moreover,it can improve SE of the presented CLD.Besides,due to better approximation,it obtains the performance close to the existing optimal approach which requires numerical search.Simulation results show that the proposed CLD with PA can achieve higher SE than the conventional CLD with equal power allocation scheme,and has almost the same performance as CLD with optimal PA.However,it has lower calculation complexity. 展开更多
关键词 cross-layer design(CLD) power allocation(PA) space-time coding spectral efficiency(SE) packet error rate(PER)
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Real-time Design Constraints in Implementing Active Vibration Control Algorithms 被引量:1
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作者 Mohammed Alamgir Hossain Mohammad Osman Tokhi 《International Journal of Automation and computing》 EI 2006年第3期252-262,共11页
Although computer architectures incorporate fast processing hardware resources, high performance real-time implementation of a complex control algorithm requires an efficient design and software coding of the algorith... Although computer architectures incorporate fast processing hardware resources, high performance real-time implementation of a complex control algorithm requires an efficient design and software coding of the algorithm so as to exploit special features of the hardware and avoid associated architecture shortcomings. This paper presents an investigation into the analysis and design mechanisms that will lead to reduction in the execution time in implementing real-time control algorithms. The proposed mechanisms are exemplified by means of one algorithm, which demonstrates their applicability to real-time applications. An active vibration control (AVC) algorithm for a flexible beam system simulated using the finite difference (FD) method is considered to demonstrate the effectiveness of the proposed methods. A comparative performance evaluation of the proposed design mechanisms is presented and discussed through a set of experiments. 展开更多
关键词 Algorithm analysis and design active vibration control (AVC) flexible beam system real-time control memory management.
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脉内频率 时延捷变雷达抗间歇采样转发干扰方法 被引量:1
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作者 牛闯 林强 +2 位作者 段敏 施端阳 谷成刚 《系统工程与电子技术》 EI CSCD 北大核心 2024年第5期1583-1598,共16页
间歇采样转发干扰凭借快速准确的采样和转发手段,利用脉压雷达的匹配滤波特性形成假目标群,严重影响目标检测和跟踪性能。针对这一问题,结合波形设计和滤波思想,设计一种脉内频率时延捷变波形,并在此基础上提出一种基于时频分析的抗间... 间歇采样转发干扰凭借快速准确的采样和转发手段,利用脉压雷达的匹配滤波特性形成假目标群,严重影响目标检测和跟踪性能。针对这一问题,结合波形设计和滤波思想,设计一种脉内频率时延捷变波形,并在此基础上提出一种基于时频分析的抗间歇采样转发干扰方法。首先,将线性调频信号划分为多个子脉冲,并在子脉冲之间增加随机时延。然后,提取未被干扰的子脉冲进行目标位置的准确判断,结合子脉冲的频率和随机时延等先验信息,利用迭代阈值分割算法去除强干扰信号。最后,通过构造时频域和时域带通滤波器分别进行子脉冲滤波和时域滤波处理。仿真实验结果表明,所提方法在不同干信比、信噪比和非同步采样情况下具有较好的抗间歇采样转发干扰性能。 展开更多
关键词 间歇采样转发干扰 波形设计 时频分析 迭代阈值分割算法
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凯文•林奇的时间城市设计思想解析与启示
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作者 胡杨 秦昕祎 +1 位作者 王德 蔚丹 《上海城市规划》 北大核心 2024年第2期1-7,共7页
凯文•林奇是20世纪最具影响力的城市设计理论家之一,其著作《此地何时:城市与变化的时代》(WhatTimeIsThis Place?)开创性地将时间概念引入城市设计,拓展了人们对城市时间性的认识,为城市设计实践提供了新的视角。系统梳理凯文•林奇的... 凯文•林奇是20世纪最具影响力的城市设计理论家之一,其著作《此地何时:城市与变化的时代》(WhatTimeIsThis Place?)开创性地将时间概念引入城市设计,拓展了人们对城市时间性的认识,为城市设计实践提供了新的视角。系统梳理凯文•林奇的时间城市设计思想,从3个层面剖析其理论体系的核心内容和创新贡献:一是揭示时间的主观性、共享性和规范性特征,提出构建兼具连续性和精确性的城市时间结构;二是从过去、现在和未来3个维度阐述塑造城市意象的时间路径;三是提出主动引导与被动适应相结合的策略,以管理城市社会和环境变化。凯文•林奇对时间在城市发展、环境塑造和生活体验中价值的思考和探讨,为推动城市设计理论创新和实践范式转型提供了宝贵的思想资源和借鉴。 展开更多
关键词 时间 凯文•林奇 城市时间性 时间城市规划与设计
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铝型材冷却初拉伸控制
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作者 蔡雄友 吴曙光 唐灏 《工业控制计算机》 2024年第4期161-162,共2页
针对铝型材加工过程中的拉伸夹具及冷却时间度量问题,设计适用于不同型号的拉伸夹具,确定了不同加工参数下的最佳冷却时间。通过优化拉伸夹具的设计和冷却时间的控制,能够提高铝型材的加工质量和生产效率。实验结果表明,该方法能够有效... 针对铝型材加工过程中的拉伸夹具及冷却时间度量问题,设计适用于不同型号的拉伸夹具,确定了不同加工参数下的最佳冷却时间。通过优化拉伸夹具的设计和冷却时间的控制,能够提高铝型材的加工质量和生产效率。实验结果表明,该方法能够有效地改善铝型材的性能和形状,具有较高的应用价值。 展开更多
关键词 铝型材加工 拉伸夹具 冷却时间 优化设计 生产效率
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