太阳能—热泵热水系统供热优化设计

针对目前大型太阳能—热泵多热源热水系统实时连续供热性能不佳和达不到最大节能效果等问题,提出以谷电时段预蓄热为核心的系统供热策略。论文优化现有太阳能—热泵热水系统构架,以天气预报为基础,应用RBF神经网络技术制定谷电时段预蓄热策略中蓄热最高水温值、蓄热水量等关键参数,并以太阳能集热器水温、蓄水箱水温水位等参数为依据,完成系统各热源及相关运行机构的启停,实现制热、蓄热、供热的协调控制。该方法能提高目前大型太阳能—热泵多热源热水系统节能效果及实时连续供热能力,为大型太阳能热水系统的控制策略提供新思路。     

Alternative approaches to the definition and identification of learning disabilities: Some questions and answers

Recent consensus reports concur in suggesting major changes in the federal regulatory approach to the identification of learning disabilities (LD). These reports recommend abandoning the IQ-discrepancy model and the use of IQ tests for identification, and also recommend incorporation of response to instruction (RTI) as one of the identification criteria. These changes are also recommended to states in the current reauthorization of the U.S. Individuals with Disabilities in Education Act (IDEA). While not mandatory, states that follow these recommendations will experience major changes in identification and treatment of students served under the LD category. This paper reviews the basis for these recommendations, summarizing four recent consensus group reports on special education that concur in suggesting these changes. Seventeen commonly asked questions about these changes are presented, with responses. In order to ensure adequate instruction for students with LD, it is essential that identification practices focus on assessments that are directly related to instruction, that any services for students who are struggling prioritize intervention over eligibility, and that special education be permitted to focus more on results and outcomes and less on eligibility and process. Identification models that incorporate RTI represent a shift in special education toward the goals of better achievement and behavioral outcomes for students identified with LD, as well as those students at risk for LD. Supported by grants from the National Institute of Child Health and Human Development, HD25802-13, “Center for the Study of Learning and Attention Disorders” (JMF); and the Office of Special Education Programs: H326Y02002, National Center for Special Education Accountability Monitoring (WAC); H324U010004, National Research Center for Learning Disabilities (DJR), and H324X010013, Preventing Reading Difficulties: A Three-Tiered Intervention Model (SRC). The National Center for Learning Disabilities also provided support for the development of this paper. The views expressed are those of the authors and should not be viewed as necessarily representative of others associated with the centers listed or the funding agencies supporting these centers.     

A Study of Burnout in International and Country of Origin Teachers

The study examined the extent to which burnout levels of teachers working in international schools differed from the burnout level of teachers working in their country of origin. All participants of the study were Canadian citizens who were educated in Canada, held Ontario College of Teachers certification and were teaching credit courses in high schools offering the Ontario curriculum under the auspice of the Ontario Ministry of Education. All teachers completed the Burnout Test Form 1 – Revised (Jerabeck, Burnout Test Form 1 – Revised, 2001) online. The study found that international teachers had a statistically lower level of burnout than teachers working in their country of origin.     

变截面桥梁在变速移动荷载作用下的动力响应

为了模拟车辆/列车通过多跨变截面桥梁时的耦合动力响应,采用有限元法将移动车辆作为移动质量处理,使用Euler-Bernoulli变截面梁单元模拟桥梁结构,讨论了移动质量在梁桥模型上作匀变速运动下的有限元离散模式.在假定变截面模式的基础上,推导了梁高呈线性变化及抛物线性变化的矩形截面梁单元刚度矩阵和质量矩阵,并对多个变速移动荷载作用下的梁桥结构动力响应进行了数值模拟.运用该方法可以使变截面梁的分析简化,计算结果可作为工程设计和科学研究时的参考.     

浅谈抒情诗的含蓄

含蓄是含有深意、藏而不露,也就是不把意思明白地说出来,含在所写的形象里,下面举几首诗来看看艺术的含蓄。