期刊文献+
共找到2,973篇文章
< 1 2 149 >
每页显示 20 50 100
Human-Robot Interaction-Based Model Predictive Control for Exoskeleton Robots Driven by Series Elastic Actuators
1
作者 Changxian Xu Keping Liu Zhongbo Sun 《IEEE/CAA Journal of Automatica Sinica》 2026年第2期486-488,共3页
Dear Editor,This letter presents a model predictive control(MPC)scheme for human-robot interaction(HRI)in a multi-joint exoskeleton robot(ER)driven by series elastic actuator(SEA).The proposed scheme in robot-in-charg... Dear Editor,This letter presents a model predictive control(MPC)scheme for human-robot interaction(HRI)in a multi-joint exoskeleton robot(ER)driven by series elastic actuator(SEA).The proposed scheme in robot-in-charge(RIC)mode facilitates the ER driven by SEA to provide the required assistance and support for the subject. 展开更多
关键词 human robot interaction model predictive assistance support series elastic actuator model predictive control series elastic actuator sea exoskeleton robot robot charge mode
在线阅读 下载PDF
Dynamics Modeling and Numerical Analysis of Rotor with Elastic Support/Dry Friction Dampers 被引量:8
2
作者 Liao Mingfu Li Yan +1 位作者 Song Mingbo Wang Siji 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2018年第1期69-83,共15页
The elastic support/dry friction damper is a type of damper which is used for active vibration control in a rotor system.To establish the analytical model of this type of damper,a two-dimensional friction model-ball/p... The elastic support/dry friction damper is a type of damper which is used for active vibration control in a rotor system.To establish the analytical model of this type of damper,a two-dimensional friction model-ball/plate model was proposed.By using this ball/plate model,a dynamics model of rotor with elastic support/dry friction dampers was established and experimentally verified.Moreover,the damping performance of the elastic support/dry friction damper was studied numerically with respect to some variable parameters.The numerical study shows that the damping performance of the elastic support/dry friction damper is closely related to the stiffness distribution of the rotor-support system,the damper location,the pressing force between the moving and stationary disk,the friction coefficient,the tangential contact stiffness of the contact interface,and the stiffness of the stationary disk.In general,the damper should be located on an elastic support which has a large vibration amplitude in order to achieve a better damping performance,and the more vibration energy in this elastic support concentrates,the better performance of the damper will be.The larger the tangential contact stiffness of the contact interface,and the stiffness of the stationary disk are,the better performance of the damper will be.There will be an optimal value of the friction force at which the damper performs best. 展开更多
关键词 ROTOR system elastic support/dry FRICTION DAMPER FRICTION model rotor′s mode UNBALANCE response
在线阅读 下载PDF
Multi-mode process monitoring based on a novel weighted local standardization strategy and support vector data description 被引量:9
3
作者 赵付洲 宋冰 侍洪波 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第11期2896-2905,共10页
There are multiple operating modes in the real industrial process, and the collected data follow the complex multimodal distribution, so most traditional process monitoring methods are no longer applicable because the... There are multiple operating modes in the real industrial process, and the collected data follow the complex multimodal distribution, so most traditional process monitoring methods are no longer applicable because their presumptions are that sampled-data should obey the single Gaussian distribution or non-Gaussian distribution. In order to solve these problems, a novel weighted local standardization(WLS) strategy is proposed to standardize the multimodal data, which can eliminate the multi-mode characteristics of the collected data, and normalize them into unimodal data distribution. After detailed analysis of the raised data preprocessing strategy, a new algorithm using WLS strategy with support vector data description(SVDD) is put forward to apply for multi-mode monitoring process. Unlike the strategy of building multiple local models, the developed method only contains a model without the prior knowledge of multi-mode process. To demonstrate the proposed method's validity, it is applied to a numerical example and a Tennessee Eastman(TE) process. Finally, the simulation results show that the WLS strategy is very effective to standardize multimodal data, and the WLS-SVDD monitoring method has great advantages over the traditional SVDD and PCA combined with a local standardization strategy(LNS-PCA) in multi-mode process monitoring. 展开更多
关键词 multiple operating modes weighted local standardization support vector data description multi-mode monitoring
在线阅读 下载PDF
Effective forecast of Northeast Pacific sea surface temperature based on a complementary ensemble empirical mode decomposition–support vector machine method 被引量:1
4
作者 LI Qi-Jie ZHAO Ying +1 位作者 LIAO Hong-Lin LI Jia-Kang 《Atmospheric and Oceanic Science Letters》 CSCD 2017年第3期261-267,共7页
The sea surface temperature (SST) has substantial impacts on the climate; however, due to its highly nonlinear nature, evidently non-periodic and strongly stochastic properties, it is rather difficult to predict SST... The sea surface temperature (SST) has substantial impacts on the climate; however, due to its highly nonlinear nature, evidently non-periodic and strongly stochastic properties, it is rather difficult to predict SST. Here, the authors combine the complementary ensemble empirical mode decomposition (CEEMD) and support vector machine (SVM) methods to predict SST. Extensive tests from several different aspects are presented to validate the effectiveness of the CEEMD-SVM method. The results suggest that the new method works well in forecasting Northeast Pacific SST at a 12-month lead time, with an average absolute error of approximately 0.3℃ and a correlation coefficient of 0.85. Moreover, no spring predictability barrier is observed in our experiments. 展开更多
关键词 Sea surface temperature complementary ensemble empirical mode decomposition support vector machine PREDICTION
在线阅读 下载PDF
Automatic target recognition of moving target based on empirical mode decomposition and genetic algorithm support vector machine 被引量:4
5
作者 张军 欧建平 占荣辉 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1389-1396,共8页
In order to improve measurement accuracy of moving target signals, an automatic target recognition model of moving target signals was established based on empirical mode decomposition(EMD) and support vector machine(S... In order to improve measurement accuracy of moving target signals, an automatic target recognition model of moving target signals was established based on empirical mode decomposition(EMD) and support vector machine(SVM). Automatic target recognition process on the nonlinear and non-stationary of Doppler signals of military target by using automatic target recognition model can be expressed as follows. Firstly, the nonlinearity and non-stationary of Doppler signals were decomposed into a set of intrinsic mode functions(IMFs) using EMD. After the Hilbert transform of IMF, the energy ratio of each IMF to the total IMFs can be extracted as the features of military target. Then, the SVM was trained through using the energy ratio to classify the military targets, and genetic algorithm(GA) was used to optimize SVM parameters in the solution space. The experimental results show that this algorithm can achieve the recognition accuracies of 86.15%, 87.93%, and 82.28% for tank, vehicle and soldier, respectively. 展开更多
关键词 automatic target recognition(ATR) moving target empirical mode decomposition genetic algorithm support vector machine
在线阅读 下载PDF
Study of component-ware & application software framework based decision support system development
6
作者 HeShengping QinZheng WangXianghua 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第1期63-68,共6页
The view that the traditional method of DSS development is outdated, which results to the diversiform disadvantages of DSS product. Therefore the ideas of application software framework based development to the genera... The view that the traditional method of DSS development is outdated, which results to the diversiform disadvantages of DSS product. Therefore the ideas of application software framework based development to the generation process of DSS is introduced and a modified flow chat of DSS development is proposed. Moreover, a formal description of the DSS software framework and its development is given. The analysis results indicates that not only does the new development flow ensure the DSS development global stability but also improves the software reusability level of the development process. 展开更多
关键词 decision support system software framework software reusability.
在线阅读 下载PDF
Telecom-Oriented Embedded Software Support Platform
7
作者 Xie Xin Lu Dongxin Miao Jing Xu Lifeng (Chengdu Institute of ZTE Corporation,Chengdu 610041,China) 《ZTE Communications》 2004年第1期18-21,共4页
This paper presents an embedded software platform used in the telecom field.The platform consists of the Virtual Operating System (VOS)layer,core layer, protection layer and module layer.It supports and simplifies upp... This paper presents an embedded software platform used in the telecom field.The platform consists of the Virtual Operating System (VOS)layer,core layer, protection layer and module layer.It supports and simplifies upper application software of telecom systems.In addition to basic modules and functions, its instance scheduling model and distributed process communication are detailed in the paper. 展开更多
关键词 Figure Telecom-Oriented Embedded software support Platform mode Linux HDLC OAM real
在线阅读 下载PDF
Improving Information Technology Infrastructure Library Service Delivery Using an Integrated Lean Six Sigma Framework: A Case Study in a Software Application Support Scenario
8
作者 Anil Kumar Raghavan Pillai Ashok Kumar Pundir L. Ganapathy 《Journal of Software Engineering and Applications》 2014年第6期483-497,共15页
Increasing competition in service businesses (eg: Information Technology, Healthcare, Education, Logistics, Distribution, Hospitality Financial and other services) is compelling corporates to adopt business improvemen... Increasing competition in service businesses (eg: Information Technology, Healthcare, Education, Logistics, Distribution, Hospitality Financial and other services) is compelling corporates to adopt business improvement philosophies and methodologies for addressing customer demands for better quality service and organizational demands for improving the profit margins through cost reduction. Many companies around the world have already implemented Information Technology Infrastructure Library (ITIL) as a way to manage and control their Information Technology (IT) Departments more effectively. These companies are now willing to improve their ITIL processes in order to become even more efficient. Lean Six Sigma is a methodology that has been suggested as a means to resolve these problems, reducing costs and improving quality. Its application in the IT Services area is becoming increasingly popular among researchers and academicians and can be used to conduct these improvements. Despite the application of lean six sigma approaches to different contexts in the service sector, the application of Lean Six Sigma approaches in service delivery specific to Information Technology Service Management (ITSM) remains largely untested. The purpose of this paper is to implement Integrated Lean Six Sigma for Software application support services and evaluate the benefits of continual service improvement over ITIL. 展开更多
关键词 Information Technology Infrastructure LIBRARY Change MANAGEMENT Configuration MANAGEMENT software Application support LEAN Six SIGMA
暂未订购
AQUAM——A Decision Support Software for Fish Farm Management
9
作者 Constanta Zoie Radulescu Marius Radulescu 《Journal of Fisheries Science》 2019年第1期1-6,共6页
farm is presented.The software called AQUAM is dedicated to fresh water fish farms.Its aim is to make an efficient management of resources through planning,monitoring,analysis and decision support.Successful planning ... farm is presented.The software called AQUAM is dedicated to fresh water fish farms.Its aim is to make an efficient management of resources through planning,monitoring,analysis and decision support.Successful planning and management requires the integration of data related to ponds,fish species,fish growth,water and energy and economic analysis.AQUAM computes farm budgets relating various costs and returns in order to determine short and long term profitability.A simulation of the profit,as a function of the fish holding density,is performed with AQUAM.The data used in the simulation are from a fish farm of semi-intensive type,located in the region Danube Delta,at village Jurilovca,Tulcea county,Romania.The fish species that were taken into account were carp and sanger. 展开更多
关键词 Decision support software FISH farm FIRM MANAGEMENT PROFIT FISH HOLDING density simulation
暂未订购
Distance Estimation and Material Classification of a Compliant Tactile Sensor Using Vibration Modes and Support Vector Machine
10
作者 S.R.GUNASEKARA H.N.T.K.KALDERA +1 位作者 N.HARISCHANDRA L.SAMARANAYAKE 《Instrumentation》 2019年第1期34-47,共14页
Many animals possess actively movable tactile sensors in their heads,to explore the near-range space.During locomotion,an antenna is used in near range orientation,for example,in detecting,localizing,probing,and negot... Many animals possess actively movable tactile sensors in their heads,to explore the near-range space.During locomotion,an antenna is used in near range orientation,for example,in detecting,localizing,probing,and negotiating obstacles.A bionic tactile sensor used in the present work was inspired by the antenna of the stick insects.The sensor is able to detect an obstacle and its location in 3 D(Three dimensional) space.The vibration signals are analyzed in the frequency domain using Fast Fourier Transform(FFT) to estimate the distances.Signal processing algorithms,Artificial Neural Network(ANN) and Support Vector Machine(SVM) are used for the analysis and prediction processes.These three prediction techniques are compared for both distance estimation and material classification processes.When estimating the distances,the accuracy of estimation is deteriorated towards the tip of the probe due to the change in the vibration modes.Since the vibration data within that region have high a variance,the accuracy in distance estimation and material classification are lower towards the tip.The change in vibration mode is mathematically analyzed and a solution is proposed to estimate the distance along the full range of the probe. 展开更多
关键词 VIBRATION based active TACTILE sensor Artificial Neural Network support vector MACHINES Distance estimation VIBRATION modeS Euler-Bernoulli beam element
原文传递
Online Fashion Retailer Bonobos Selects Gerber Technology's YuniquePLM^(TM) Industry-Tailored Software to Support Rapid Growth and Fast-Paced Product Innovation
11
《China Textile》 2010年第5期16-16,共1页
Tolland,Connecticut,USA-Gerber Technology,a business unit of Gerber Scientific, Inc.(NYSE:GRB) and a world leader in automated CAD/CAM and PLM solutions for the apparel and flexible materials industry,announces that f... Tolland,Connecticut,USA-Gerber Technology,a business unit of Gerber Scientific, Inc.(NYSE:GRB) and a world leader in automated CAD/CAM and PLM solutions for the apparel and flexible materials industry,announces that fast-growing internet retailer Bonobos,Inc. has selected the YuniquePLM product 展开更多
关键词 Industry-Tailored software to support Rapid Growth and Fast-Paced Product Innovation Online Fashion Retailer Bonobos Selects Gerber Technology’s YuniquePLM flexible NYSE GRB CAM TM
在线阅读 下载PDF
基于信号特征提取和GWO-SVM的气液两相流流型识别方法
12
作者 刘升虎 王颖梅 +2 位作者 魏海梦 邢亚敏 党瑞荣 《中国测试》 北大核心 2026年第1期165-171,共7页
为研究气液两相流的动态特性,并提高气液流型识别的准确性,提出一种基于信号特征提取与GWO-SVM的水平管道气液两相流流型识别方法。该方法利用环形电导传感器采集测量数据,在完成数据预处理的基础上,对信号时域特征参数进行提取。同时,... 为研究气液两相流的动态特性,并提高气液流型识别的准确性,提出一种基于信号特征提取与GWO-SVM的水平管道气液两相流流型识别方法。该方法利用环形电导传感器采集测量数据,在完成数据预处理的基础上,对信号时域特征参数进行提取。同时,采用变分模态分解对电导波动信号进行分析,通过计算各分量与原始信号的Spearman相关系数,筛选出与原始信号相关性较高的本征模态函数,计算能量比作为频域特征参数。最终,将时频域特征参数输入GWO-SVM进行流型识别。实验结果显示,该方法对三种流型的识别准确率达95.7%,与传统SVM和PSO-SVM方法相比,GWO-SVM在流型识别方面展现出更高的准确率和鲁棒性。 展开更多
关键词 流型识别 特征提取 灰狼优化算法 支持向量机 变分模态分解
在线阅读 下载PDF
FMD结合小波包模糊熵和RBMO-SVM的滚动轴承故障诊断
13
作者 陶伟 欧阳名三 +1 位作者 周莉 纪京生 《兵器装备工程学报》 北大核心 2026年第3期243-255,共13页
为解决电机轴承故障诊断中非平稳振动信号特征提取困难导致分类精度不足的问题,提出了一种特征模态分解(FMD)结合小波包模糊熵与红嘴蓝鹊优化算法(RBMO)优化支持向量机(SVM)的智能诊断方法。利用FMD的自适应滤波器组对振动信号进行分解... 为解决电机轴承故障诊断中非平稳振动信号特征提取困难导致分类精度不足的问题,提出了一种特征模态分解(FMD)结合小波包模糊熵与红嘴蓝鹊优化算法(RBMO)优化支持向量机(SVM)的智能诊断方法。利用FMD的自适应滤波器组对振动信号进行分解,以最小包络熵为目标函数并提取故障特征模态;通过小波包模糊熵量化模态分量的非线性特征,构建高区分度的特征向量;采用红嘴蓝鹊优化算法优化SVM参数,提升模型泛化能力,将特征向量导入RBMO-SVM模型,完成模型训练及故障识别任务。经公开数据集和自建实验平台数据集的双重验证结果表明,该方法在公共数据集上实现了92.5%~95.83%的诊断准确率,自制实验平台单故障和复合故障诊断准确率达98.33%和95.83%,该方案在复杂工况下具有一定的适用性。 展开更多
关键词 特征模态分解 小波包模糊熵 红嘴蓝鹊优化算法 支持向量机 轴承故障诊断
在线阅读 下载PDF
单层全预制装配式楼板建筑结构自由振动分析
14
作者 罗维刚 赵叶宁 赵山洋 《计算力学学报》 北大核心 2026年第1期101-107,131,共8页
为了研究预制装配式结构楼板的板块振动对整个建筑结构动力特性的影响,以单层全预制装配式楼板建筑结构为例,将预制板块简化为集中质量,每个预制板块与梁间的干式连接支撑节点简化为阻尼弹簧的支撑节点,由此将集中质量附加于支撑梁上,... 为了研究预制装配式结构楼板的板块振动对整个建筑结构动力特性的影响,以单层全预制装配式楼板建筑结构为例,将预制板块简化为集中质量,每个预制板块与梁间的干式连接支撑节点简化为阻尼弹簧的支撑节点,由此将集中质量附加于支撑梁上,两端部预制板块与竖向抗侧力体系一同简化为梁的弹性支座,由此给出了附加任意数量MSD系统的弹性支承均质梁分析模型,并基于Euler-Bernoulli梁理论和Wu提出的通过一组有效质量代替弹簧-阻尼-质量系统而推导出的矩阵传递计算方法,推导了该模型固有频率理论解。结合工程算例,用有限元相互验证了理论求解固有频率的准确性,最后讨论了考虑预制板块振动对全预制装配式楼板建筑结构的固有振动特性和带来的影响,为类似工程提供理论支撑和参考。 展开更多
关键词 预制装配式楼板 装配建筑固有频率 弹性支承均质梁 集中质量弹簧阻尼系统 模态振型
在线阅读 下载PDF
“5E”教学模式导入宏观经济学课程的教学创新研究
15
作者 刘航 张佳瑞 《高教学刊》 2026年第5期50-53,共4页
宏观经济学是分析一国经济总体运行规律和政策作用机制的一门理论性基础课程,其教学模式应随着实践发展而动态调整。该文通过归纳多所高校教学创新的实践经验,提出“5E”教学模式导入宏观经济学课程的可行方案,包括吸引、探究、解释、... 宏观经济学是分析一国经济总体运行规律和政策作用机制的一门理论性基础课程,其教学模式应随着实践发展而动态调整。该文通过归纳多所高校教学创新的实践经验,提出“5E”教学模式导入宏观经济学课程的可行方案,包括吸引、探究、解释、迁移和评价五个序贯步骤,并归纳出一系列支撑措施,以促进学生主动学习、深度思考和知识应用能力的全面提升,为培养深刻了解中国现实、有强烈时代责任感和掌握现代经济学分析工具的高水平人才提供一定启示。 展开更多
关键词 宏观经济学 “5E”教学模式 宏观经济治理 教学创新 支撑体系
在线阅读 下载PDF
基于改进VMD和SVM方法的滚动轴承故障诊断 被引量:1
16
作者 何晓良 苏春 张玉茹 《东南大学学报(自然科学版)》 北大核心 2026年第2期322-332,共11页
为解决旋转部件早期振动故障信号存在的特征微弱、非平稳等问题,提出一种基于改进变分模态分解(VMD)及支持向量机(SVM)的故障诊断方法。采用改进的野马算法(IWHO)优化VMD中的惩罚因子α和模态数K以实现参数自动寻优,采用适应度函数选择... 为解决旋转部件早期振动故障信号存在的特征微弱、非平稳等问题,提出一种基于改进变分模态分解(VMD)及支持向量机(SVM)的故障诊断方法。采用改进的野马算法(IWHO)优化VMD中的惩罚因子α和模态数K以实现参数自动寻优,采用适应度函数选择最小包络熵。利用优化后的VMD完成振动信号分解,得到振动信号的固有模态函数(IMF)。在此基础上,采用峭度准则选取前5阶IMF分量以计算时频域特征,构建特征向量;将特征向量输入SVM中完成训练,实现旋转部件的故障分类。以滚动轴承试验数据集为例,验证方法有效性。结果表明:所提出的方法能有效处理非平稳振动信号,针对数据集中轴承4种运行状态诊断的准确率达99.17%;在模拟噪声干扰环境下,模型仍能保持95.8%以上的诊断精度。 展开更多
关键词 变分模态分解 支持向量机 改进野马算法 故障诊断
在线阅读 下载PDF
不同支撑方式下的滚珠丝杠进给系统横向振动特性分析
17
作者 丁金磊 陈恩伟 +1 位作者 丁凯 陆益民 《合肥工业大学学报(自然科学版)》 北大核心 2026年第3期302-308,共7页
为研究滚珠丝杠进给系统的横向振动特性,文章采用假设模态法和拉格朗日能量法建立系统的横向振动动力学模型,利用丝杠边界条件推导丝杠横向振动的频率方程,并求解出假设模态函数;将所提出的数学模型与有限元方法进行对比分析,验证模型... 为研究滚珠丝杠进给系统的横向振动特性,文章采用假设模态法和拉格朗日能量法建立系统的横向振动动力学模型,利用丝杠边界条件推导丝杠横向振动的频率方程,并求解出假设模态函数;将所提出的数学模型与有限元方法进行对比分析,验证模型的正确性和精度范围,分析系统在两端弹性、固定-简支、两端固定3种支撑方式下的系统固有频率和模态振型的振动特性。结果表明:弹性支撑下,若将边界条件简化为固定支撑,会使频率计算结果偏大,且阶数越高,两者差距越大;丝杠横向模态振型的节点位置与节点数量会随着工作台位置变化而发生改变。文章分析结果对于理解并改善滚珠丝杠进给系统的横向振动有着一定的实际应用价值。 展开更多
关键词 滚珠丝杠 横向振动 支撑方式 弹性支撑 假设模态函数
在线阅读 下载PDF
基于导波多模态特征的法兰螺栓松动监测
18
作者 王文君 程嘉辉 +1 位作者 范雨 李琳 《航空动力学报》 北大核心 2026年第1期255-268,共14页
透射过法兰连接的多种导波模态携带了大量连接状态信息,有望实现一种高精度的非原位监测技术。基于导波多模态特征对具有8颗螺栓的法兰连接进行松动监测。为了捕捉多种波模态,提出了能够选择性激励和传感单一波模态的压电阵列设计方案,... 透射过法兰连接的多种导波模态携带了大量连接状态信息,有望实现一种高精度的非原位监测技术。基于导波多模态特征对具有8颗螺栓的法兰连接进行松动监测。为了捕捉多种波模态,提出了能够选择性激励和传感单一波模态的压电阵列设计方案,仿真和试验验证了波模态换能器的选择性能。采用波模态换能器控制4种波模态透射法兰,分两个阶段监测螺栓松动:是否松动和松动位置。结果发现:导波多模态特征不仅能够有效表征螺栓是否松动还蕴含丰富的螺栓松动位置信息,结合支持向量机后对松动位置识别的正确率高达94.6%。 展开更多
关键词 法兰螺栓 螺栓松动 导波多模态 波模态换能器 支持向量机
原文传递
基于虚拟原型的概念设计描述模型V-desModel 被引量:2
19
作者 杨 强 郭 阳 +2 位作者 彭宇行 李思昆 杨 强 《软件学报》 EI CSCD 北大核心 2002年第4期748-753,共6页
传统的概念设计方法由于缺乏真实感的交互手段,难以直观表达设计者的意图.基于虚拟原型的概念设计不仅能为设计者提供逼真的虚拟设计环境,而且充分体现了现代设计的成本低、周期短以及灵活性强等特点.针对概念设计的特点以及虚拟原型的... 传统的概念设计方法由于缺乏真实感的交互手段,难以直观表达设计者的意图.基于虚拟原型的概念设计不仅能为设计者提供逼真的虚拟设计环境,而且充分体现了现代设计的成本低、周期短以及灵活性强等特点.针对概念设计的特点以及虚拟原型的特征分类,提出了基于虚拟原型的概念设计模型V-desModel,其核心是利用产品视图模型描述设计对象,将虚拟特征概念融入视图模型中,并采用可扩展“三维实体-约束图”来描述设计对象之间的约束关系.V-desModel模型能有效地支持基于虚拟原型的概念设计过程,较好地解决了概念设计中产品虚拟原型的逼真性要求和设计信息不完备之间的矛盾,不仅极大地扩展了概念设计实施的手段和范围,而且更有利于概念设计阶段创造性的发挥. 展开更多
关键词 计算机辅助设计 虚拟原理型 概念设计描述模型 V-desmodel CAD
在线阅读 下载PDF
上一页 1 2 149 下一页 到第
使用帮助 返回顶部