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V Model of E-Learning Using Gagne Nine Steps of Education
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作者 Hasan Al-Shalabi Swidan Andraws +1 位作者 Adnan I. Alrabea A. V. Senthil Kumar 《Journal of Software Engineering and Applications》 2012年第11期850-854,共5页
This paper presents a V-model of e-learning using the well-known Gagne nine steps for quality education. Our suggested model is based on our experience at the computer engineering departments at AL-Hussein Bin Talal U... This paper presents a V-model of e-learning using the well-known Gagne nine steps for quality education. Our suggested model is based on our experience at the computer engineering departments at AL-Hussein Bin Talal University, the University of Jordan and Albalqa Applied University. We applied the recommendations of the nine steps methodology to the e-learning environment. The V model suggested in this paper came up as a result of such application. Although this V model can be subject to some tuning and development in the future it proved to be highly efficient and easy to implement for the teacher and the student. 展开更多
关键词 E-LEARNING EDUCATIONAL System NINE STEPS E-LEARNING v-model Quality EDUCATION
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Vue框架下V-model指令的应用研究
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作者 范敏 《计算机应用文摘》 2024年第16期108-109,114,共3页
V-model是Vue框架中的一种内置API指令,本质上是一种语法糖,负责监听用户的输入事件以更新数据,主要用于表单元素的双向数据绑定。通过V-model指令,可以实现前端与后端数据的同步更新,大幅简化了前端表单处理的工作流程。
关键词 vue框架 v-model指令 组件通信
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基于Model/View/Controller的电子商务研究 被引量:2
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作者 许文韬 顾君忠 《计算机应用研究》 CSCD 北大核心 2002年第10期19-22,共4页
分析了传统电子商务系统的缺陷 ,电子商务发展趋势 ,分析了M/V/C(Model/View/Controller)技术 ,提出了基于M/V/C电子商务并且分析了其体系结构及框架结构 ,以及在此框架之上构建电子商务的方法。
关键词 电子商务 体系结构 框架结构 INTERNET 模型 视图 控制器
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基于V形记忆曲线的汽车轮毂造型衍生设计方法
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作者 孙利 陈永亮 +3 位作者 艾雯 孙倩哲 于鸿飞 吴俭涛 《机械设计》 CSCD 北大核心 2024年第3期163-169,共7页
为提高汽车轮毂造型设计的效率,增强品牌造型识别度,提出一种高效的轮毂造型衍生创新设计方法。通过分析轮毂V形记忆曲线的变化规律和特点,总结出两类V形记忆曲线,并根据控制点数量分别进行了定量化表达;以轮毂造型的5个设计要素为基础... 为提高汽车轮毂造型设计的效率,增强品牌造型识别度,提出一种高效的轮毂造型衍生创新设计方法。通过分析轮毂V形记忆曲线的变化规律和特点,总结出两类V形记忆曲线,并根据控制点数量分别进行了定量化表达;以轮毂造型的5个设计要素为基础,提取轮毂骨骼的特征并建立运算法则,构建基于V形记忆曲线的轮毂造型衍生设计方法;通过参数化实现造型构建方案衍生,验证了该方法的可行性。研究结果表明:基于V形记忆曲线的轮毂造型衍生设计方法提高了轮毂设计效率,实现了轮毂造型创新及提升品牌特征延续的设计目标,为同类型产品的创新设计提供参考。 展开更多
关键词 汽车轮毂造型 造型衍生设计 v形记忆曲线 轮毂骨骼 参数化构建
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基于改进V-Net的颅内出血病灶分割算法 被引量:1
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作者 徐睿 周长才 宋宇 《长春工业大学学报》 CAS 2024年第1期66-72,共7页
针对颅内出血病灶分割不精确问题提出一种改进V-Net算法。用深度可分离卷积去替换普通卷积,加快模型训练速度。在编码器和解码器中分别加入通道注意力机制和混合注意力机制。通过引入SE模块和CBAM模块,强化原始网络的特征提取能力以及... 针对颅内出血病灶分割不精确问题提出一种改进V-Net算法。用深度可分离卷积去替换普通卷积,加快模型训练速度。在编码器和解码器中分别加入通道注意力机制和混合注意力机制。通过引入SE模块和CBAM模块,强化原始网络的特征提取能力以及自适应调整特征图中不同通道之间的权重,提高模型的性能表现。对比实验结果表明,改进后的V-Net分割评价指标DSC达到0.732,比原始V-Net提升4.4%。 展开更多
关键词 深度学习 v-Net模型 深度可分离卷积 颅内出血
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MODEL-BASED DEVELOPMENT OF REAL-TIME SOFTWARE SYSTEM FOR ELECTRONIC UNIT PUMP SYSTEM 被引量:1
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作者 YU Shitao YANG Shiwei YANG Lin GONG Yuanming ZHUO Bin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第1期25-30,共6页
A real-time operating system (RTOS), also named OS, is designed based on the hardware platform of MC68376, and is implemented in the electronic control system for unit pump in diesel engine. A parallel and time-base... A real-time operating system (RTOS), also named OS, is designed based on the hardware platform of MC68376, and is implemented in the electronic control system for unit pump in diesel engine. A parallel and time-based task division method is introduced and the multi-task software architecture is built in the software system for electronic unit pump (EUP) system. The V-model software development process is used to control algorithm of each task. The simulation results of the hardware-in-the-loop simulation system (HILSS) and the engine experimental results show that the OS is an efficient real-time kernel, and can meet the real-time demands of EUP system; The built multi-task software system is real-time, determinate and reliable. V-model development is a good development process of control algorithms for EUP system, the control precision of control system can be ensured, and the development cycle and cost are also decreased. 展开更多
关键词 Real-time operating system (RTOS) Multi-task v-model development Hardware-in-the-loop simulation system(HILSS) Electronic unit pump (EUP)
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IGBT模块V-I特性曲线簇建模及其结温提取应用
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作者 刘红涛 王颢棋 +3 位作者 张晓康 任林涛 罗雨 汪飞 《电气工程学报》 CSCD 北大核心 2024年第3期14-22,共9页
绝缘栅双极型晶体管(Insulated gate bipolar transistor,IGBT)以其高效率、大容量和低成本等特点在新能源发电及储能、高压直流输电、电力牵引和电气化交通等领域应用非常广泛。然而一旦IGBT模块发生故障,将打破相关装置和设备的正常... 绝缘栅双极型晶体管(Insulated gate bipolar transistor,IGBT)以其高效率、大容量和低成本等特点在新能源发电及储能、高压直流输电、电力牵引和电气化交通等领域应用非常广泛。然而一旦IGBT模块发生故障,将打破相关装置和设备的正常运行状态,引发一系列连锁事故,造成人员伤害和严重的经济损失。根据一项调查统计结果,光伏电站大约34%的可靠性问题是由IGBT模块故障所引发的,因此,IGBT模块可靠性问题愈发受到关注。相关研究成果表明,IGBT模块的结温与模块可靠性问题之间存在密切的关系,如何能够快速准确地获取当前IGBT模块的实时结温是IGBT模块可靠性研究的关键。通过对IGBT模块的V-I输出特性曲线进行深入分析和研究,提出一种表征IGBT模块导通压降、结温和集电极电流关系的建模方法。利用该方法建立的表征模型可以方便快捷地提取IGBT模块结温,并通过试验验证了基于该建模方法的IGBT模块结温提取策略的有效性。除此之外,该建模方法考虑到了模块键合线老化的影响,并给出了相应的模型校正方法和结温提取策略。 展开更多
关键词 IGBT模块 v-I特性 建模 结温
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MODELING OF DYNAMIC RECRYSTALLIZATION OF Ti6A14V ALLOY USING A CELLULAR AUTOMATON APPROACH 被引量:1
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作者 J.W. Zhao H. Ding +3 位作者 W.J. Zhao F.R. Cao H.L. Hou Z.Q. Li 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2008年第4期260-268,共9页
A cellular automaton (CA) model is established to simulate dynamic recrystallization (DRX) in the β single-phase field of Ti6Al4 V alloy, and the kinetics during DRX processing has been analyzed. The model employ... A cellular automaton (CA) model is established to simulate dynamic recrystallization (DRX) in the β single-phase field of Ti6Al4 V alloy, and the kinetics during DRX processing has been analyzed. The model employed considers the influences of dynamic recovery, nucleation rate, strain rate and dislocation density on DRX, and practical deformation parameters, such as temperature, strain and strain rate on DRX have been considered in the simulation. The simulated DRX grain size and DRX grain shape agree well with the experimental results, which shows the availability and lea- sibility of the cellular automaton method for the simulation of DRX. The result of kinetics analysis of DRX reveals that the Avrami exponent is variable ranging from 2.4 to 2.9, which increases with the increase of strain rate. 展开更多
关键词 Ti6A4 v alloyi Dynamic recrystallization KINETICS modelING Cellular automaton
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UWB Channel Modeling Improvement in Indoor Line-of-Sight (LOS) Environments
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作者 Vahid Tabataba Vakili Dariush Abbasi-Moghadam Mostafa Yahyaabadi 《International Journal of Communications, Network and System Sciences》 2010年第11期870-876,共7页
Channel measurement and modeling is an important issue when designing ultra wideband (UWB) communication systems. A Precise model of the channel response is inevitable for designing an ultra wideband telecommunication... Channel measurement and modeling is an important issue when designing ultra wideband (UWB) communication systems. A Precise model of the channel response is inevitable for designing an ultra wideband telecommunication system. In this article signal propagation in indoor environment and LOS condition is evaluated and the appropriate model of this scenario is presented. Parameters such as the power delay profile, mean excess delay, delay spread, “NP10dB” are analyzed and simulated. Based on analysis results, the proposed model is presented. This model is based on Two-cluster approach but its average power delay profile is described with power function and cluster time of arrival is modeled by the modified exponential distribution. Finally UWB channel parameters of proposed model, Saleh and Valenzuela (S-V) and Two-cluster models are compared. Measurement and simulation results show that considerable improvement for mean excess delay, delay spread and “NP10dB” of proposed model comparing with S-V and Two-cluster model, this means the channel is better described, which mean the channel is described more precisely. 展开更多
关键词 Channel modeling S-v model Power DELAY PROFILE Ultra WIDEBAND
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Liver Segmentation in CT Images Based on DRLSE Model
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作者 黄永锋 齐萌 严加勇 《Journal of Donghua University(English Edition)》 EI CAS 2012年第6期493-496,共4页
Liver segmentation in CT images is an important step for liver volumetry and vascular evaluation in liver pre-surgical planning. In this paper, a segmentation method based on distance regularized level set evolution(D... Liver segmentation in CT images is an important step for liver volumetry and vascular evaluation in liver pre-surgical planning. In this paper, a segmentation method based on distance regularized level set evolution(DRLSE) model was proposed, which incorporated a distance regularization term into the conventional Chan-Vese (C-V) model. In addition, the region growing method was utilized to generate the initial liver mask for each slice, which could decrease the computation time for level-set propagation. The experimental results show that the method can dramatically decrease the evolving time and keep the accuracy of segmentation. The new method is averagely 15 times faster than the method based on conventional C-V model in segmenting a slice. 展开更多
关键词 liver segmentation distance regularized level set evolution (DRLSE) model Chan-vese (C-v) model region growing
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MODELING v_P AND Q ON EXPLOSION SEISMOLOGY DATA IN NE TIBET
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作者 A. Galvé 1, A. Hirn 1, J. Gallart 2, Jiang Mei 3, Wang Youxue 3 2 IJA, CSIC, calle Lluis Sole i Sabaris, Barcelona 08028, Spain 3 Chinese Academy of Geological Sciences, Baiwanzhuang Roa 《地学前缘》 EI CAS CSCD 2000年第S1期331-331,共1页
A Sino\|French refraction\|reflection experiment was conducted in October 1998 in the northeastern edge of the Tibetan Plateau from the Qiang Tang through the north Kunlun block.The successive wide\|angle reflection t... A Sino\|French refraction\|reflection experiment was conducted in October 1998 in the northeastern edge of the Tibetan Plateau from the Qiang Tang through the north Kunlun block.The successive wide\|angle reflection traveltime curves are modeled trying to keep the minimum structure. First results obtained along this 700km transect, show the contrast of crustal structure between the three blocks crossed and the state of the crustal material.North of the Kunlun suture, a change of the Moho depth appears from the Qaidam basin, 55km, to the south approaching the Kunlun range, 65km. But the main crustal characteristic is a great thickness of upper crustal material and the lack of lower crust. This implies a crustal average velocity of 6 2km/s, which is much lower than the worldwide average of 6 45km/s. Interpretations of this crustal column may consider, assuming the crust had been normal that while its upper part thickened the lower one was transported away, underthrust to the south or to depth. Alternatively the velocity in the lower crust may have been changed by metamorphism. 展开更多
关键词 v p Q modelING SEISMOLOGY NE TIBET
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Bianchi Type-V Cosmological Model with Linear Equation of State in Brans-Dicke Theory of Gravitation
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作者 Sharad Kandalkar Seema Samdurkar 《International Journal of Astronomy and Astrophysics》 2014年第3期429-436,共8页
A Bianchi type-V space time is considered with linear equation of state in the scalar tensor theory of gravitation proposed by Brans and Dicke. We use the assumption of constant deceleration parameter and power law re... A Bianchi type-V space time is considered with linear equation of state in the scalar tensor theory of gravitation proposed by Brans and Dicke. We use the assumption of constant deceleration parameter and power law relation between scalar field &oslash;and scale factor R to find the solutions. Some physical and kinematical properties of the model are also discussed. 展开更多
关键词 Bianchi Type-v model BRANS-DICKE Theory LINEAR Equation of State
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The 3+1 SysML View-Model in Model Integrated Mechatronics
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作者 Kleanthis Thramboulidis 《Journal of Software Engineering and Applications》 2010年第2期109-118,共10页
Software is becoming the driving force in today’s mechatronic systems. It does not only realize a significant part of their functionality but it is also used to realize their most competitive advantages. However, the... Software is becoming the driving force in today’s mechatronic systems. It does not only realize a significant part of their functionality but it is also used to realize their most competitive advantages. However, the traditional development process is wholly inappropriate for the development of these systems that impose a tighter coupling of software with electronics and mechanics. In this paper, a synergistic integration of the constituent parts of mechatronic systems, i.e. mechanical, electronic and software is proposed though the 3+1 SysML view-model. SysML is used to specify the cen-tral view-model of the mechatronic system while the other three views are for the different disciplines involved. The widely used in software engineering V-model is extended to address the requirements set by the 3+1 SysML view-model and the Model Integrated Mechatronics (MIM) paradigm. A SysML profile is described to facilitate the application of the proposed view-model in the development of mechatronic systems. 展开更多
关键词 Systems Engineering System modeling Mechatronic Component model Driven Development model In-tegrated MECHATRONICS SYSML Profile v-model IEC61499
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Systematical Development of NVH Engineering for Vehicle Electrical Powertrain Based on an Optimized V-Model
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作者 Shaoyou Shi Kaiyu Yu Zecheng Zhong 《World Journal of Mechanics》 2021年第2期7-15,共9页
For systematical NVH development of vehicle (especially for mass-production passenger vehicles) electric powertrain, an optimized V-Model is designed and has been implemented in the entire component-vehicle developmen... For systematical NVH development of vehicle (especially for mass-production passenger vehicles) electric powertrain, an optimized V-Model is designed and has been implemented in the entire component-vehicle development, which integrates three individual branches: simulation, validation and optimization. Compared to the V-models in the traditional sense, this optimized V-model is not only driven by requirement and task accomplishment but also maximum optimization of NVH system performance. In this case, developing procedures are capable to be efficiently iterated and the NVH engineering can be expanded into 3D with this V-model. 展开更多
关键词 v-model NvH (Nosie vibration and Harshness) SEP (System Engineering Process) Electrical Powertrain MBS (Multi-Body System) Acoustic Electromagnetic Gear Mesh Topology Optimization
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Characterization and Modelling of High Temperature Flow Behaviour of V Modified 2.25Cr-1Mo Heat Resistant Steel Plate
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作者 刘自立 刘春明 +1 位作者 DING Jianhua ZHANG Hanqian 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第1期192-199,共8页
In order to study the high temperature flow behaviour of the V modified 2.25Cr-1Mo steel plate to guide the industrial rolling practice, the hot compression tests were carried out at the temperatures from 900 ℃ to 11... In order to study the high temperature flow behaviour of the V modified 2.25Cr-1Mo steel plate to guide the industrial rolling practice, the hot compression tests were carried out at the temperatures from 900 ℃ to 1150 ℃ and the strain rates from 0.01s^-1 to 1 s^-1 on Thermecmastor-Z equipment. Based on the experimental data of the hot compression tests, a kind of Arrhenius-type constitutive equation was developed.The equation can accurately show the relationship between the flow stress and the deformation temperature, the strain and the strain rate. The measured true stress-true strain curves exhibit two kinds of flow stress curves. Moreover, the forming mechanisms of these two types curves were explained by softening, wok hardening theory as well as metallographic and hardness experimental results. The accuracy of the developed Arrheniustype constitutive equation was identified by three kinds of statistic parameters and also by comparison of the measured and predicted data. The reasonable value of the three types of statistic parameters and the good agreement between the experimental and predicted data can confirm the validity of the developed Arrheniustype constitutive equation for V modified 2.25 Cr-1 Mo heat resistant steel plate. 展开更多
关键词 flow behaviour CHARACTERIZATION modelling v MODIFIED 2.25CR-1MO STEEL heat resistant STEEL PLATE
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Analytical Model for GaAs MESFET with High Pinchoff Voltage
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作者 Chahrazed Kaddour Cherifa Azizi Saade Edine Khemissi Mourad Zaabat Yasemina Saidi 《材料科学与工程(中英文A版)》 2013年第12期853-858,共6页
关键词 MESFET器件 夹断电压 GAAS 金属半导体场效应晶体管 解析模型 移动特性 电子电路 静态模型
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V型球阀的米浆流量实验研究
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作者 陆正杰 王一泉 +1 位作者 杜张博 黄俊枫 《阀门》 2024年第3期315-317,341,共4页
建立一种符合实际生产的米浆流量模型对提高米粉生产标准化至关重要。对比以往的一次函数、二次函数和指数函数孔口流量模型,提出一种幂函数孔口流量模型,利用软件Origin的LMA算法的非线性最小二乘法拟合4种函数流量模型。结果表明:4种... 建立一种符合实际生产的米浆流量模型对提高米粉生产标准化至关重要。对比以往的一次函数、二次函数和指数函数孔口流量模型,提出一种幂函数孔口流量模型,利用软件Origin的LMA算法的非线性最小二乘法拟合4种函数流量模型。结果表明:4种模型均通过了卡方检验及F检验,幂函数的调整R平方最高且残差平方和最小,说明幂函数流量模型拟合效果最好。为孔口流量模型提供了一种新的幂函数参考。 展开更多
关键词 孔口排放模型 v型球阀 阀门开度 水位差 流量特性 拟合检验
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基于系统工程V模型的课程思政教学探索与实践——以智能网联汽车技术概论课程为例
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作者 艾力夏提·阿不力孜 张家辉 +1 位作者 李建新 薛喜红 《汽车实用技术》 2024年第13期136-141,共6页
为了培养智能网联汽车专业高素质技术技能人才,以智能网联汽车技术概论课程为例,深入分析目前高职院校智能网联汽车技术专业课程思政建设存在的问题,以“提升职业能力、塑造价值观”为导向,构建了基于系统工程V模型的“分析设计、评价... 为了培养智能网联汽车专业高素质技术技能人才,以智能网联汽车技术概论课程为例,深入分析目前高职院校智能网联汽车技术专业课程思政建设存在的问题,以“提升职业能力、塑造价值观”为导向,构建了基于系统工程V模型的“分析设计、评价体系建立、目标验证”三位一体课程思政教学体系,并对课程思政元素挖掘与融入路径进行详细说明。探索将该课程思政教学体系在高职院校专业人才培养过程中实践落实,并在教学实践过程中根据“学生评教、效果评价、综合评价”三个维度的评价结果动态调整课程思政设计方案,以期解决智能网联汽车技术专业课程思政教学效果不突出的问题,为高职院校课程思政建设提供借鉴。 展开更多
关键词 系统工程v模型 课程思政 智能网联汽车技术 评价体系
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收纳用横编V形折叠结构织物设计
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作者 邓燕丽 石彬琳 +2 位作者 董智佳 丛洪莲 马丕波 《毛纺科技》 CAS 北大核心 2024年第10期9-15,共7页
为探究节约储物收纳空间的柔性针织织物组织与结构创新可行性,以易收纳横编V形折叠结构包为开发对象,展开结构建模、组织设计与试样开发。首先分析折叠结构原理、V形折叠的分类与折痕线类型,在此基础上对横编V形多循环折叠织物进行工艺... 为探究节约储物收纳空间的柔性针织织物组织与结构创新可行性,以易收纳横编V形折叠结构包为开发对象,展开结构建模、组织设计与试样开发。首先分析折叠结构原理、V形折叠的分类与折痕线类型,在此基础上对横编V形多循环折叠织物进行工艺结构建模,以M1 PLUS软件与STOLL电脑横机作为开发工具,选取76.9 tex再生涤纶竹节纱与12.2 tex/(48 f)热熔涤纶长丝为原料,采用罗纹、双反面、吊针、凸条和浮线组织进行折痕线的结构设计与样品制备。结果表明:折叠结构织物在最大程度缩小自身体积的同时具备大容量可扩展柔性储物收纳的优点,结合材料搭配、上机试样、参数调节与定形工序等建立V形折叠包结构模型与折痕线组织设计实现了可扩容易收纳且环保的横编V形折叠结构织物的快速生产,为横编三维立体折叠结构织物的设计与开发提供了工艺方法与开发实例。 展开更多
关键词 收纳 v形折叠结构 折叠结构建模 折痕线工艺 织物结构设计 纬编工艺
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ENHANCING GROUND RESOLUTION OF TM6 BASED ON MULTI-VARIATE REGRESSION MODEL AND SEMI-VARIOGRAM FUNCTION
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作者 MA Hongchao LI Deren 《Geo-Spatial Information Science》 2001年第1期43-49,共7页
It is well known that Landsat TM images are the most widely used remote sensing data in various fields.Usually,it has 7 different electromagnetic spectrum bands,among which the sixth one has much lower ground resoluti... It is well known that Landsat TM images are the most widely used remote sensing data in various fields.Usually,it has 7 different electromagnetic spectrum bands,among which the sixth one has much lower ground resolution compared with the other six bands.Nevertheless,it is useful in the study of rock spectrum reflection,geothermal resources exploration,etc.To improve the ground resolution of TM6 to the level as that of the other six bands is a problem .This paper presents an algorithm based on the combination of multivariate regression model with semivariogram function which can improve the ground resolution of TM6 by "fusing" the data of other six bands.It includes the following main steps: (1) testing the correlation between TM6 and one of TM15,7.If the correlation coefficient between TM6 and another one is greater than a given threshold value,then select the band to the regression analysis as an argument.(2) calculating the size of the template window within which some parameters needed by the regression model will be calculated; (3) replacing the original pixel values of TM6 by those obtained by regression analysis; (4) using image entropy as a measurement to evaluate the quality of the fused image of TM6.The basic mechanism of the algorithm is discussed and the V C ++ program for implementing this algorithm is also presented.A simple application example is given in the last part of this paper,showing the effectiveness of the algorithm. 展开更多
关键词 multi-variate regression model semi-variogram FUNCTION image fusion TEMPLATE WINDOW v C++ PROGRAMMING
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