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卷入·跟评:指向素养的“PDCA故事演讲”能力提升——以小学生“口头表达与交流”为例
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作者 董晴倩 《当代家庭教育》 2023年第5期243-245,共3页
在新课程改革不断推进且持续深入的发展过程中,小学生的口头表达与交流能力得到更多的重视,也得到了广泛的关注。小学阶段语文教学过程中,提高口头表达与交流能力在一定意义上成为重要的价值维度和发展力度。本文紧密围绕“提升学生口... 在新课程改革不断推进且持续深入的发展过程中,小学生的口头表达与交流能力得到更多的重视,也得到了广泛的关注。小学阶段语文教学过程中,提高口头表达与交流能力在一定意义上成为重要的价值维度和发展力度。本文紧密围绕“提升学生口头表达与交流能力”这一宏观性命题做微观策略实施研究。基于“PDCA故事演讲”活动从内容、角色、空间及成果四个维度展开卷入式训练活动,借助逐步进阶,联结跟进的多元评价方式,旨在提升学生的口头表达与交流能力,强化核心素养目标。 展开更多
关键词 卷入 跟评 PDCA故事演讲 口头表达与交流能力
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POSTERIOR CRAMR-RAO BOUNDS ANALYSIS FOR PASSIVE TARGET TRACKING 被引量:1
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作者 Zhang Jun Zhan Ronghui 《Journal of Electronics(China)》 2008年第1期84-88,共5页
For the problem of deterministic parameter estimate, the theoretical lower bound of esti- mate error is the Cramér-Rao bound; while for random parameter, the lower bound of estimate error is generally termed by P... For the problem of deterministic parameter estimate, the theoretical lower bound of esti- mate error is the Cramér-Rao bound; while for random parameter, the lower bound of estimate error is generally termed by Posterior Cramér-Rao Bound (PCRB). Under the background of passive tracking where the target's state can be seen as a time-varying random parameter, PCRB of the state estimate error is analyzed in this paper, and the relation between PCRB and varied condition is also fully in- vestigated using different simulation examples. The presented analytical method provides a theoretical base for performance assessment of all kinds of suboptimal estimate algorithms used in practice. 展开更多
关键词 Passive target tracking Posterior Cramer-Rao Bound (PCRB) Nonlinear filtering State estimate
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Performance Evaluation of New Two Axes Tracking PV-Thermal Concentrator
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作者 Luis C. Chea Hakan Hakansson Bjirn Karlsson 《Journal of Civil Engineering and Architecture》 2013年第12期1485-1493,共9页
The overall problem with PV (photovoltaic) systems is the high cost for the photovoltaic modules. This makes it interesting to concentrate irradiation on the PV-module, thereby reducing the PV area necessary for obt... The overall problem with PV (photovoltaic) systems is the high cost for the photovoltaic modules. This makes it interesting to concentrate irradiation on the PV-module, thereby reducing the PV area necessary for obtaining the same amount of output power. The tracking capability of two-axes tracking unit driving a new concentrating paraboloid for electric and heat production have been evaluated. The reflecting optics consisting of flat mirrors provides uniform illumination on the absorber which is a good indication for optimised electrical production due to series connection of solar cells. The calculated optical efficiency of the system indicates that about 80% of the incident beam radiation is transferred to the absorber. Simulations of generated electrical and thermal energy from the evaluated photovoltaic thermal (PV/T) collector show the potential of obtaining high total energy efficiency. 展开更多
关键词 Solar concentrating photovoltaic/thermal systems tracking concentrating systems.
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Comparison of GUF and Monte Carlo methods to evaluate task-specific uncertainty in laser tracker measurement 被引量:1
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作者 杨景照 李国喜 +2 位作者 吴宝中 龚京忠 王杰 《Journal of Central South University》 SCIE EI CAS 2014年第10期3793-3804,共12页
Measurement uncertainty plays an important role in laser tracking measurement analyses. In the present work, the guides to the expression of uncertainty in measurement(GUM) uncertainty framework(GUF) and its supplemen... Measurement uncertainty plays an important role in laser tracking measurement analyses. In the present work, the guides to the expression of uncertainty in measurement(GUM) uncertainty framework(GUF) and its supplement, the Monte Carlo method, were used to estimate the uncertainty of task-specific laser tracker measurements. First, the sources of error in laser tracker measurement were analyzed in detail, including instruments, measuring network fusion, measurement strategies, measurement process factors(such as the operator), measurement environment, and task-specific data processing. Second, the GUM and Monte Carlo methods and their application to laser tracker measurement were presented. Finally, a case study involving the uncertainty estimation of a cylindricity measurement process using the GUF and Monte Carlo methods was illustrated. The expanded uncertainty results(at 95% confidence levels) obtained with the Monte Carlo method are 0.069 mm(least-squares criterion) and 0.062 mm(minimum zone criterion), respectively, while with the GUM uncertainty framework, none but the result of least-squares criterion can be got, which is 0.071 mm. Thus, the GUM uncertainty framework slightly underestimates the overall uncertainty by 10%. The results demonstrate that the two methods have different characteristics in task-specific uncertainty evaluations of laser tracker measurements. The results indicate that the Monte Carlo method is a practical tool for applying the principle of propagation of distributions and does not depend on the assumptions and limitations required by the law of propagation of uncertainties(GUF). These features of the Monte Carlo method reduce the risk of an unreliable measurement of uncertainty estimation, particularly in cases of complicated measurement models, without the need to evaluate partial derivatives. In addition, the impact of sampling strategy and evaluation method on the uncertainty of the measurement results can also be taken into account with Monte Carlo method, which plays a guiding role in measurement planning. 展开更多
关键词 task-specific uncertainty laser tracker measurement uncertainty evaluation Monte Carlo method uncertainy framework(GUF)
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Analysis and evaluation of band-limited ray tracing method
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作者 WANG Rui SUN Jianguo 《Global Geology》 2018年第3期203-208,共6页
From the analysis and the contrast of band-limited ray tracing method based on Kirchhoff integral, it was found that the method performs many approximations in the derivation process and omits the derivative term of t... From the analysis and the contrast of band-limited ray tracing method based on Kirchhoff integral, it was found that the method performs many approximations in the derivation process and omits the derivative term of the phase factor in the Kirchhoff integral. Numerical calculations and analysis show that the omission of cor-relation terms in Kirchhoff integrals has a non-negligible effect on the calculation results, and the different terms in the Kirchhoff integral have different effects on different frequency ranges. The method can be applied to ve-locity models containing complex interfaces without changing waves and continuous media. the velocity model and can be extended to elastic waves and continuous media. 展开更多
关键词 ray tracing limited band ray path
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Dynamic Tracking and Comprehensive Evaluation on the Natural Resources Security Elements and System in China
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作者 Yao Yulong Zhou Hong 《Chinese Journal of Population,Resources and Environment》 2010年第2期32-39,共8页
System theory,pressure-state-response and drivingpressure-state-impact-response model have been applied to establishing China's dynamic tracking evaluation system of natural resources security in this article.Base... System theory,pressure-state-response and drivingpressure-state-impact-response model have been applied to establishing China's dynamic tracking evaluation system of natural resources security in this article.Based on analytic hierarchy process and Delphi methods,the natural resources security situation has been evaluated systematically from 1991 to 2007.The result showed that the overall level of China's natural resources security presented a downtrend from 1991 to 2007.The basic reasons are the pressure indicators such as population,GDP,natural resources trade increased gradually,resulting in tension and fragility of natural resources security. 展开更多
关键词 natural resources security indicator system dynamic tracking comprehensive evaluation
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Research on the Teaching Evaluation System based on Feedback Tracking Technology under Cloud Computing Environment
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作者 Ping Li 《International Journal of Technology Management》 2015年第12期1-3,共3页
In this paper, we conduct research on the teaching evaluation system based on the feedback tracking technology under the cloud computing environment. Teaching evaluation is an important work of teaching management dep... In this paper, we conduct research on the teaching evaluation system based on the feedback tracking technology under the cloud computing environment. Teaching evaluation is an important work of teaching management department. According to the traditional mode of work, must first into classroom, through questionnaire survey, fill out a form scale, obtain first-hand teaching evaluation data, and then input the data into the computer, after check again the data statistics and analysis which is not efficient. To optimize the procedure, we use the cloud computing to assist finalizing the general evaluation steps which is innovative and meaningful. 展开更多
关键词 Evaluation System Feedback Tracking Cloud Computing Systematic Design
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Comment on "Compare Quantum Operation Sensitivity for Different Distance Measures"
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作者 高云峰 冯健 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第11期824-826,共3页
We make comments on the conclusions of the paper:'Compare Quantum Operation Sensitivity for DifferentDistance Measures' [Commun.Theor.Phys.53 (2010)635],and give a physical example to describe the non-equivale... We make comments on the conclusions of the paper:'Compare Quantum Operation Sensitivity for DifferentDistance Measures' [Commun.Theor.Phys.53 (2010)635],and give a physical example to describe the non-equivalenceof the fidelity and the trace distance.We prove that the fidelity is not more sensitive to a quantum operation than thetrace distance. 展开更多
关键词 FIDELITY trace distance quantum operation
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A quantitative attribute-based benchmark methodology for single-target visual tracking
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作者 Wen-jing KANG Chang LIU Gong-liang LIU 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2020年第3期405-422,共18页
In the past several years,various visual object tracking benchmarks have been proposed,and some of them have been used widely in numerous recently proposed trackers.However,most of the discussions focus on the overall... In the past several years,various visual object tracking benchmarks have been proposed,and some of them have been used widely in numerous recently proposed trackers.However,most of the discussions focus on the overall performance,and cannot describe the strengths and weaknesses of the trackers in detail.Meanwhile,several benchmark measures that are often used in tests lack convincing interpretation.In this paper,12 frame-wise visual attributes that reflect different aspects of the characteristics of image sequences are collated,and a normalized quantitative formulaic definition has been given to each of them for the first time.Based on these definitions,we propose two novel test methodologies,a correlation-based test and a weight-based test,which can provide a more intuitive and easier demonstration of the trackers’performance for each aspect.Then these methods have been applied to the raw results from one of the most famous tracking challenges,the Video Object Tracking(VOT)Challenge 2017.From the tests,most trackers did not perform well when the size of the target changed rapidly or intensely,and even the advanced deep learning based trackers did not perfectly solve the problem.The scale of the targets was not considered in the calculation of the center location error;however,in a practical test,the center location error is still sensitive to the targets’changes in size. 展开更多
关键词 Visual tracking Performance evaluation Visual attributes Computer vision
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Orbit determination for Chang'E-2 lunar probe and evaluation of lunar gravity models 被引量:31
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作者 Li PeiJia Hu XiaoGong +5 位作者 Huang Yong Wang GuangLi Jiang DongRong Zhang XiuZhong Cao JianFeng Xin Nan 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第3期514-522,共9页
The Unified S-Band (USB) ranging/Doppler system and the Very Long Baseline Interferometry (VLBI) system as the ground tracking system jointly supported the lunar orbit capture of both Chang'E-2 (CE-2) and Chang... The Unified S-Band (USB) ranging/Doppler system and the Very Long Baseline Interferometry (VLBI) system as the ground tracking system jointly supported the lunar orbit capture of both Chang'E-2 (CE-2) and Chang'E-1 (CE-1) missions. The tracking system is also responsible for providing precise orbits for scientific data processing. New VLBI equipment and data processing strategies have been proposed based on CE-1 experiences and implemented for CE-2. In this work the role VLBI tracking data played was reassessed through precision orbit determination (POD) experiments for CE-2. Significant improve- ment in terms of both VLBI delay and delay rate data accuracy was achieved with the noise level of X-band band-width syn- thesis delay data reaching 0.2-0.3 ns. Short-arc orbit determination experiments showed that the combination of only 15 min's range and VLBI data was able to improve the accuracy of 3 h's orbit using range data only by a 1-1.5 order of magnitude, confirming a similar conclusion for CE-1. Moreover, because of the accuracy improvement, VLBI data was able to contribute to CE-2's long-arc POD especially in the along-track and orbital normal directions. Orbital accuracy was assessed through the orbital overlapping analysis (2 h arc overlapping for 18 h POD arc). Compared with about 100 m position error of CE-l's 200 kin x 200 km lunar orbit, for CE-2's 100 km x 100 km lunar orbit, the position errors were better than 31 and 6 m in the radial direction, and for CE-2's 15 km^100 km orbit, the position errors were better than 45 and 12 m in the radial direction. In addi- tion, in trying to analyze the Delta Differential One-Way Ranging (ADOR) experiments data we concluded that the accuracy of ADOR delay was dramatically improved with the noise level better than 0.1 ns and systematic errors better calibrated, and the Short-arc POD tests with ADOR data showed excellent results. Although unable to support the development of an independent lunar gravity model, the tracking data of CE-2 provided evaluations of different lunar gravity models through POD. It is found that for the 100 km x 100 km lunar orbit, with a degree and order expansion up to 165, JPL's gravity model LP165P did not show noticeable improvement over Japan's SGM series models (100x100), but for the 15 kmxl00 km lunar orbit, a higher de- gree-order model can significantly improve the orbit accuracy. 展开更多
关键词 Chang'E-2 VLBI orbit determination lunar gravity field
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Using eye tracking to evaluate the usability of animated maps 被引量:14
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作者 DONG WeiHua LIAO Hua +2 位作者 XU Fang LIU Zhao ZHANG ShaoBo 《Science China Earth Sciences》 SCIE EI CAS 2014年第3期512-522,共11页
Cartographic animation has been developed and widely used in geo-visualisation and many other areas in recent years.The usability of animated maps is a key characteristic affecting map users’effectiveness and efficie... Cartographic animation has been developed and widely used in geo-visualisation and many other areas in recent years.The usability of animated maps is a key characteristic affecting map users’effectiveness and efficiency in accomplishing tasks.In this paper,an eye tracking approach was proposed as a visual analytics method to evaluate the usability of animated maps by capturing participants’eye movement data and quantitatively analysing the accuracy(effectiveness)and response time(efficiency)of users’task completion.In the study,a set of animated traffic maps represented by three important visual variables(colour hue,size and frequency)was used for the usability evaluation.The experimental results showed that the usability of these three visual variables for cartographic animation affects the usability of animated maps.Red,yellow,and aqua were found to convey map information more effectively than other colour hues.Size was found to be more usable than colour hues for both animated maps and static maps.Usability was not found to be proportional to the playback rate of animated maps.Furthermore,the usability of the frequency,colour hue,and size was found to be related to the display’s size.We hope that the analysis approach presented in this paper and the results of this study will be of help in the design of cartographic animation displays with better usability. 展开更多
关键词 USABILITY eye tracking approach animated maps visual variables
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