Improved fast intra prediction algorithm of H.264/AVC     

Liu Qiong  Hu Rui-min  Zhu Li  Zhang Xin-chen  Han Zhen 《浙江大学学报(A卷英文版)》2006,7(1):101-105

With advanced prediction modes of intra prediction, intra coding of H.264/AVC offers significant coding gains compared with previous video coding standards. It uses an important tool called Lagrangian rate-distortion optimization (RDO) technique to decide the best coding mode for a block, but the computational burden is extremely high. In this paper, we proposed an improved fast intra prediction algorithm including block type selection and mode decision algorithm based on analysis of edge feature of a block. Our algorithm filters out unlikely block type and candidate modes to reduce the RDO calculations. Experimental results showed that the proposed algorithm can reduce the computation complexity of intra prediction from 52.90% to 56.31%, with 0.04 dB PSNR degradation and 2% increase of bit rate.  相似文献   

Triadic interaction in clinical task-based interviews with mathematics teachers     

Boris Koichu  Guershon Harel 《Educational Studies in Mathematics》2007,65(3):349-365

A clinical task-based interview can be seen as a situation where the interviewer–interviewee interaction on a task is regulated by a system of explicit and implicit norms, values, and rules. This paper describes how documenting and mapping triadic interaction among the interviewer, the interviewee, and the knowledge negotiated can be used to increase procedural replicability of the interview and accuracy of drawn conclusions about the interviewee’s thinking process. Excerpts from interviews with 25 inservice mathematics teachers working on a task to make up a problem whose solution requires division of two fractions are discussed. The excerpts illustrate the relationship between methodological decisions taken by the interviewer during the interview and the applicability of the interview output to the research questions. A divergent analysis of the interviews with these teachers, which spanned over two years and were conducted by four interviewers, is used to offer a framework for analyzing data collected in clinical task-based interviews.  相似文献   

Giving Education a Bad Name: Bookish Boys in Contemporary American School Stories     

David Aitchison 《Children‘s Literature in Education》2018,49(1):47-60

This article discusses contemporary American school stories that appear to advocate learning and literacy as a democratic good, but actually undermine democratic possibilities by teaching young readers to think of academic inquiry as a means to selfish, petty ends. Since “learning” and “literacy” are catchwords for educators dedicated to remedying neoliberal inequities, it is understandable why authors of school fiction such as Andrew Clements and Tommy Greenwald are celebrated by educators for foregrounding the exploits of bookish characters. Yet, as is shown, the narrative arcs in works such as Frindle by Clements and Charlie Joe Jackson’s Guide to Not Reading by Greenwald ultimately endorse the market consciousness, deregulation, and excessive individualism for which neoliberalism is known. Examining the ways in which these two novels intersect with ongoing debates over literacy standards, learning outcomes, and academic honesty, it is argued that the didactic-pedagogical imagination in contemporary American fiction for young people has a biased conception of student development and life preparedness, ideologically at odds with democratic curriculum provision.  相似文献   

Visualization of structured packing with laser induced fluorescence technique: Two-dimensional measurement of liquid concentration distribution     

刘伯潭  申言同  张会书  刘春江  唐忠利  袁希钢 《天津大学学报(英文版)》2016,22(5):466-472

A method of using laser induced fluorescence(LIF)technique was applied to two-dimensional measurement of the liquid concentration distribution in the 250Y structured packing sheet. The experimental structured packing sheet was made of perspex so that the laser could pass through it. The visualization of the distribution of the liquid concentration in the structured packing sheet was realized. The calibration of the thickness and liquid concentration was carried out firstly and the regression formula I=kcd was acquired, in which concentration c and the liquid film thickness d were both considered. Then the liquid feed of uniform tracer(rhodamine)concentration entered the perspex structured packing from the top under different spraying densities. The corresponding thickness of liquid film on the packing was calculated. Finally, tracer(rhodamine)with a high concentration was injected only at one fixed point of the structured packing under different spraying densities of the liquid. With the known liquid film thickness, the concentration distribution of the tracer can be calculated inside the structured packing sheet.  相似文献   

Humanitas Emptor: Reconsidering Recent Trends and Policy in Science Teacher Education     

Dana L. Zeidler  Benjamin C. Herman  Michael P. Clough  Joanne K. Olson  Sami Kahn  Mark Newton 《Journal of Science Teacher Education》2016,27(5):465-476

  相似文献   

Establishing a Center to Support Faculty Research     

Laura Goodwin  Elizabeth Kozleski  Rodney Muth  Lynn K. Rhodes  Kim Kennedy White 《Innovative Higher Education》2005,30(4):251-268

This article describes the establishment in fall 2002 of a School of Education Research Center designed to support faculty in increasing productivity and quality in research. Details are provided about center goals, services, staffing, space, resources, and logistics during the first year of operation. In addition, data are shared about faculty usage of the Center, the level of faculty satisfaction with center services in the first year, and initial increases in faculty productivity. The article concludes with plans for continued data collection to monitor the impact of the Center, a discussion of lessons learned at this point in the Center's development, and possibilities for the evolution of the Center. All authors are at the University of Colorado, Denver. Laura Goodwin, Ph.D., University of Colorado at Boulder, is Interim Associate Vice Chancellor for Faculty Affairs and continues to serve as a Faculty Research Associate. Elizabeth Kozleski, Ed.D., University of Northern Colorado, is the Associate Dean for Research in the School of Education. Lynn Rhodes, Ed.D., Indiana University, is the Dean of the School of Education. Rodney Muth, Ph.D., Claremont Graduate School, is a professor of Administrative Leadership and Policy Studies in the school and chaired the Research Center Advisory Board. Kim Kennedy White, M.A., University of Oregon, was the original School of Education Research Center Coordinator and was responsible for collecting most of the data included in this study.  相似文献   

基于核密度估计多样性采集的背景建模算法     

毛燕芬  施鹏飞 《上海大学学报(英文版)》2005,9(6):506-509

1IntroductionBackground subtraction methods are extensively ex-ploited for moving object detection in videos in manyapplications ,such as traffic monitoring[1],human mo-tion capture[2]and video surveillance[3]. The centralidea behind such methods is to segment foreground ini mage sequences taken from a fixed camera by com-paring each newframe to a model of the scene back-ground . Therefore , correctly and efficiently modelingand updating the background model is one of the mostchallenging aspec…  相似文献   

掺杂剂与基质材料能量匹配的红色有机发光二极管     

朱文清  蒋雪茵  张志林  许少鸿 《上海大学学报(英文版)》2003,7(2):191-195

1　Introduction　Organiclight emittingdiodes(OLEDs)haveattract edconsiderableattentionduetoitsgreatpotentialinefficiency ,low voltage ,large area ,lightweight ,andfull colorflat paneldisplays[1,2 ] .Forfull colordis plays ,itisnecessarytohaveefficientred ,green ,andblueemitterswithappropriatechromaticity .Bycom parisonwiththehighperformanceofblueandgreenOLEDs ,theperformanceandpurechromaticityofredOLEDsarestillrelativelypoor .UsuallyredOLEDsareimprovedbydopingreddyesintohostmaterialswit…  相似文献   

Designing Curriculum-Based Mathematics Professional Development for Kindergarten Teachers     

Drew Polly  Christie S. Martin  Jennifer R. McGee  Chuang Wang  Richard G. Lambert  David K. Pugalee 《Early Childhood Education Journal》2017,45(5):659-669

This study examines the influence of a year-long mathematics professional development program on Kindergarten teachers’ beliefs, content knowledge, instructional practices, and their students’ achievement. The professional development program is grounded in the theoretical construct of learner-centered professional development and focuses on supporting teachers’ integration of standards-based pedagogies aligned with the Common Core State Standards in Mathematics. Data analysis included examining 15 Kindergarten teachers’ mathematics content knowledge, their beliefs about mathematics, their enactment of student-centered pedagogies, and student achievement on curriculum-based assessments. Findings indicated that teachers adopted more student-centered pedagogies and embraced more student-centered beliefs about mathematics teaching during their time in the project. Further, Kindergarten teachers also demonstrated gains in their mathematical content knowledge, and those content knowledge gains were linked to gains in student achievement.  相似文献   

Improving content area reading comprehension of Spanish speaking English learners in Grades 4 and 5 using web-based text structure instruction     

Kausalai Wijekumar  Bonnie J. F. Meyer  Puiwa Lei  Anita C. Hernandez  Diane L. August 《Reading and writing》2018,31(9):1969-1996

Reading and comprehending content area texts is important for academic and professional success as well as life skills necessary to maintain good health and quality lifestyle. Spanish speaking English language learners have shown poor performance on high-stakes assessments in reading comprehension. The number of Spanish speaking English learners (ELs) in our schools continues to increase at a fast pace, and therefore it is imperative that we address their reading comprehension needs swiftly and effectively. The text structure strategy has shown positive results on comprehension outcomes in many research studies with students at Grades 2, 4, 5, and 7. This study is the first implementation of instruction about the text structure strategy expressly designed to accommodate the linguistic and comprehension needs of Spanish speaking ELs in Grades 4 and 5. Strategy instruction on the web for English learners (SWELL) was designed to deliver instruction about the text structure strategy to Spanish speaker English learners. A randomized controlled study with pre and post-tests was conducted with 14 classrooms at fourth-grade and 17 classrooms at fifth-grade in high poverty schools where over 85% of students were Spanish speaking bilinguals or ELs. Analysis of data using multi-level models show moderate to large-effects favoring the students in the SWELL classrooms over the business as usual control classrooms on important measures such as a standardized reading comprehension test and main idea and cloze tasks. This research has practical implications for the use of web-based tools to provide high-quality and supportive instruction to improve Spanish speaking ELs reading comprehension skills.  相似文献