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张玲丽 《武汉职业技术学院学报》2013,(5):49-53
主要研究基于Packet Tracer（简称PT）的虚拟局域网（VLAN）配置测试系统.使用PT的Extension模块的Activity Wizard功能,开发网络设备学习的模拟测试系统.通过这种测试系统,在进行网络设备配置的同时,同步显示完成配置的进度、正确和错误的具体点并评分,方便教师指导和学生自测,提高了教学和学习效率和效果. 相似文献
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针对人工测量木材径级效率低、存在主观误差等问题,基于机器视觉技术开发了一个木材径级自动测量系统。利用Opencv设计算法流程,采用背景减法、均值滤波、固定阈值分割得到木材径向截面轮廓的二值图像,再利用边缘检测和椭圆拟合算法拟合轮廓的椭圆,将椭圆短轴像素点数转换为木材直径。利用C#编写人机交互界面显示木材直径的测量结果并将分类结果传输给下位机。经过实验验证,该系统的软件算法流程能够准确测量木材直径,得到的测量绝对误差在0.8 cm以内,单根测量平均时间为0.895 s,有效提高了木材径级测量的效率,为实现木材径级的自动化分拣提供支撑。 相似文献
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INTRODUCTION Oil-water-gas multiphase mixed transport in oil pipe is extensively used in ocean oil industries. How to measure the volumetric fractions of oil-water-gas multiphase flow is an important subject of study in the oil industry. Related research work was started in the 1980s. The measurement of component ratios in multiphase flows using γ-ray attenuation was first suggested by Abouelwafa and Kendall (1980), and the technique has been used in many current com- mercial multiphase… 相似文献
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Non-dispersive solvent extraction (NDSE) with p-xylene as extractant was employed as a novel separation method to recover both p-toluic (PT) acid and water from purified terephthalic acid (PTA) wastewater. The mass transport behavior of PT acid from aqueous solution to p-xylene was investigated by experiments and numerical simulation. Experiments showed that NDSE is feasible and effective. Residual PT acid in the raffinate can be reduced to lower than the permitted limit of wastewater re-use (100 g/m3) with extraction time longer than 60 s in industrial conditions. A mathematical model of PT acid mass transport was developed to optimize the membrane module performance. The model was validated with the experimental results with relative errors of less than 6%. Numerical analysis for mass transfer through the lumen side, the porous membrane layer, and the shell side showed that PT acid transport in the aqueous solution is the rate determining step. The effects of the membrane and operating parameters on membrane module performance were investigated by means of computational simulations. The key parameters suggested for industrial NDSE design are: fiber inner radius r1=200–250 µm, extraction time te=50–60 s, aqueous/organic volumetric ratio a/o=9.0, and temperature T=318 K. 相似文献
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基于非线性宇称时间对称的无线电能传输系统,是一种能在一定耦合区间内保持恒定高效率传输的鲁棒性系统。宇称-时间对称(PT对称)无线电能传输系统,能够在较大范围内实现对耦合谐振线圈位置的不敏感性,在该区间内可对负载进行恒定的功率传输。基于耦合模理论对S-P型结构的PT对称无线电能传输电路进行分析,观察其在不同耦合区间内系统的传输效率随耦合系数的变化情况进行分析。最后通过matlab等软件进行仿真,结果表明在强耦合区域内系统传输效率不随耦合系数变化而变化,且能保持高效传输,在弱耦合区域耦合系数对系统的传输效率有很大的影响。 相似文献
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林可春 《辽宁科技学院学报》2017,19(2)
针对目前对汽车的制动性能检测的要求越来越高,对汽车制动性能检测系统进行了研究及设计.对该系统的总体框架及检测系统软件流程进行了设计,同时以LabView为平台设计了汽车制动性能测试系统程序界面,最后通过实验仿真,对仿真及实车实验数据进行了对比分析,其结果表明在汽车ABS有效时实车测量数值与传感器之间的误差仅有0.12%,实车测量数值与汽车轮胎和制动平板之间的摩擦力的相对误差是0.35%,当ABS 无效时,误差是0.56%,误差均在1%以内,从而证明了该系统的有效性,同时为今后ABS汽车制动力检测提供了理论依据. 相似文献
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陈垚 《商洛师范专科学校学报》2014,(2):13-16
对液压系统参数变化影响电网进行了分析,采用单设备实验测检与系统配电仿真相结合的方式,设计了航空液压系统用电仿真模型,并在SIMULINK下搭建模型进行仿真。该模型通过单设备实验测试获得参数曲线,避免了理论建模时由于条件假设产生的误差,使仿真结果更接近实际情况。该仿真方法不仅提高了仿真速度,还简化了系统模型,仿真结果与实验结果近似,具有工程应用前景。 相似文献
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流体输送综合实验平台的开发与应用 总被引：3，自引：0，他引：3
介绍了具有计算机在线数据采集与控制功能的流体输送综合实验平台的开发,及其在实验教学中的应用。平台合理地将流体输送所涉及的流动能量损失、流量计标定、输送机械性能测定与选型等实验内容融合,实现了过程、实验和研究的一体化,开出了一系列综合性、研究性实验内容。 相似文献
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The current study examines the impact of a three-week precision teaching (PT) intervention programme through the Irish language on a group of primary school pupils’ Irish reading fluency. The study employed a mixed factorial experimental design. Thirty-six Irish primary school pupils who were learning Irish as a second language were recruited for this study. Participants were divided evenly into two groups: experimental and control (N?=?18). Participants completed tests of isolated sight word reading fluency and contextualised reading fluency before and after the PT intervention programme. The experimental group was exposed to the PT programme, which focused on isolated Irish vocabulary, while the control group experienced typical teaching of Irish. The results of a one-way multivariate analysis of variance and a series of dependent-samples t-tests revealed that in contrast to the control group, the experimental group exhibited a significant increase in both isolated sight word reading fluency and contextualised reading fluency following the intervention. This study emphasises the potential value of utilising PT to aid second language learning, not only for increasing isolated sight word reading fluency, but also for enhancing contextualised reading fluency. 相似文献
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通常由于受实验设备、场所和时间等限制无法很好满足课程实验的需求,而且在“检测与转换技术”课程实验时存在容易损坏实验器件等问题,鉴于此,本文讨论了利用Authorware软件开发的该课程的实验模拟系统,使学生不受地点和时间限制通过计算机就可以进一步了解实验原理,实验过程,提高实验兴趣。 相似文献
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虚拟仿真驾驶座舱评测是汽车人机交互设计教学中的重要一环。依托汽车交互实验室的研究背景和条件,在主观和行为测量基础上,将皮电测量引入研究生课程,在整个设计流程中发挥学生主观能动性,自主展开命题、设计调研、实验设计和可用性评测。以评测车载多屏互动音乐系统为例,学生在驾驶仿真台架上完成两种设计方案实验评测。实验表明,使用中控触屏的皮电高于使用方向盘按键,即中控触屏心理负荷更低,结果与中控触屏系统可用性量表分值更高且任务用时更短趋势一致,说明皮电测量与主观和行为测量结合能有效评测汽车人机交互界面设计的可用性。学生通过课程学习掌握皮电测量评测方法,为自主展开研究奠定基础。 相似文献
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Outcomes for methods to accelerate thinking skills involving some peer interaction have been more consistently positive than those for purely teacher‐directed or materials‐led methods. However, methods involving mainly or only peer interaction are rare. This paper describes and evaluates such a method for peer tutoring in thinking skills, which scaffolds interactive discourse based on a differentiated real book the tutorial pair has chosen to read together. This pilot study aimed to partial the impact on quality of thinking of a peer‐tutored thinking intervention from that of a peer‐tutored reading intervention, controlling for time on task and amount of peer interactivity. Experimental peer tutees were a whole class (n=28) of seven‐year‐olds; experimental tutors a whole class (n=31) of 11‐year‐olds. Comparison tutees were a whole class (n=27) of seven‐year‐olds; comparison tutors a whole class (n=30) of 11‐year‐olds. Classes/teachers within the same school were randomly assigned to conditions. In Phase 1, a paired reading intervention was implemented for six weeks for all groups. In Phase 2, the experimental classes of tutors and tutees engaged in the “paired thinking” (PT) method for 10 weeks, while the comparison group continued with paired reading. Both treatments involved one 20‐minute session weekly. Pre‐ and post‐test assessment of thinking skills and attitude to reading for all participants was conducted and post hoc subjective feedback gathered from participants. The experimental (PT) tutees showed significantly better performance in thinking skills than comparison (PR only) tutees, and some evidence of improved attitudes to reading. However, this was not true for the experimental (PT) tutors. Subjective feedback was very positive from the PT tutees and class teachers, but less positive from the PT tutors. Given the brevity and low cost in time and resources of the treatment, the finding of significant differences in measured thinking skills for the PT tutees is considered encouraging. Recommendations for refining organizational aspects of the implementation of PT and for future research are made. 相似文献
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权重系数矩阵是光学过程层析成像(optical process tomography，简称光学PT)技术中非常重要的参数之一，它的传统计算是基于人工测算，其缺点是烦琐、且极其耗时。因此，本文利用Visual C 语言实现了光学过程层析成像系统扇束阵列传感器结构权重系数矩阵的即时计算。为光学敏感场灵敏度分布的计算、图像重建仿真以及光学PT系统的实现节省了时间，缩短了研究周期。 相似文献
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基于智能化的传感器教学实验仿真系统是为辅助传感器测量与虚拟仪器实践教学平台的使用而设计的仿真测量软件系统，它由Access软件和LabVIEW软件编写，基于智能化的传感器教学实验仿真系统为实现实验环节的网络化教学做出探索性工作。对实验环节现代化具有重要的实用价值。 相似文献
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U形渠道断面流速分布规律试验研究 总被引：2，自引：0，他引：2
U形渠道是灌区广泛推广的灌溉渠道，其具有占地面积少、水头损失小等特点。但U形渠道流速分布规律及其流量测量仍处于研究阶段。对灌区计划用水、科学用水和节约水资源等工作造成了很大的影响，因此U形渠道测流技术是亟待解决的问题。本文从试验的角度使用断面测流方法，针对三种不同规格的U形渠道测量断面，运用数学拟合方法，探求其流速分布规律，并分析出了相应的U形渠道过水断面流量的积分求和公式，以求对以后的U形渠道量水工作有所帮助。 相似文献
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Influence of measurement errors on structural damage identification using artificial neural networks
The effect of measurement errors on structural damage identification using artificial neural networks (ANN) was investigated
in this study. By using back-propagation (BP) networks with proper input vectors, numerical simulation tests for damage detection
on a six-storey frame were conducted with measurement errors in deterministic as well as probabilistic senses. The identifiability
using ANN for damage location and extent was studied for the cases of measurement errors with different degrees. The results
showed that there exists a critical level of measurement error beyond which the probability of correct identification is sharply
decreased. The identifiability using the neural networks in the presence of modeling and measurement errors is finally verified
using experimental data on a two-storey steel frame.
Project supported by Hong Kong Polytechnic University. 相似文献
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INFLUENCE OF MEASUREMENT ERRORS ON STRUCTURAL DAMAGE IDENTIFICATION USING ARTIFICIAL NEURAL NETWORKS 总被引：2，自引：0，他引：2
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天线实验教学仿真系统的研究 总被引：4，自引：0，他引：4
采用Visual Basic软件开发工具设计并实现了天线实验教学仿真系统。首先给出了系统的构成,讨论了天线模型的建立、天线方向性图和天线输入阻抗的测量,最后介绍了系统的软件实现过程。所设计的天线实验教学仿真系统实现了天线的方向性图和输入阻抗的测量过程。应用表明,天线实验教学仿真系统具有交互性好、实用和逼真等特点。 相似文献