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171.
本文介绍了常微分方程模型的三种归结方法,并以实例加以说明,旨在使大家对其有明确的认识,为以后建立常微分方程模型提供有力的帮助。  相似文献   
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173.
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   
174.
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   
175.
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   
176.
“读先乎句”是《马氏文通》自创的语法理论之一,它指的是“读”在先、“句”在后组成的一种“读+句”句型。“读先乎句”可归为今天的3种句型的8个小类。《马氏文通》在讲“读先乎句”时举“君子食无求饱,居无求安”为例,被不少语言学家认为不妥,其实并没有什么不妥。  相似文献   
177.
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   
178.
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   
179.
用求积分方程特征值方法求出长球波函数 ,再进行外推 ,重建出由于缺角度而引起数据不完全时的图象 ,避开了反演中的求Radon反变换问题 .通过模型验证 ,在角度缺少较大的情况下所建立的算法在效率、精度、稳定性等方面都有较好结果  相似文献   
180.
本文认为隐喻、移位法与拟人法这三个英语辞格是人类思维中三种性质不同的方式的产物,并分析了其表现形式的不同。  相似文献   
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