无人直升机旋翼转速控制器设计

针对无人机的特殊性以及对电机动态性能的要求,设计了一种以ARM芯片LPC2148为核心的旋翼转速控制器。首先分析了直升机的飞行特点以及原旋翼转速控制器的不足,设计基于EKF和矢量控制的新旋翼转速控制器,并对扩展卡尔曼滤波法和矢量控制的模块进行说明,且给出了MATLAB仿真结果,验证了控制系统的正确性。     

从高凉县郡沿革看俚区羁縻式分治

据史籍中秦汉至南朝时期高凉县、郡沿革及相关俚族记载,以分析梁末前历朝对高凉俚区的羁縻式分划统治。认为汉晋岭南始现俚族应与秦汉以来历朝通过边地郡县对瓯、骆、乌浒等族的羁縻式统治有关,从西晋至南朝分置的羁縻性政区可以看出,梁末前历朝逐步推进对高凉俚区的羁縻式分划统治。通过以上羁縻性政区及相关行政制度,加快了高凉俚区部分俚僚如冼氏俚族与汉族间的融合。     

商务英语写作修辞意识的构建及其培养方法

商务英语写作修辞意识的框架系统包含几十种成对的语言表达手段、写作修辞方法、写作修辞现象以及它们体现的写作修辞原则和倾向。在教学中,培养商务英语写作修辞意识的具体方法主要有二：通过实例对比分析树立明确的商务英语写作修辞意识;通过写作训练建立商务英语写作修辞意识,写作训练的具体训练法有修改提高法和完形选择法。     

介孔纳米γ-Al_2O_3对稀土镧（Ⅲ）的吸附性能研究

以溴化十六烷基三甲铵（CTAB）为模板剂,采用溶胶-凝胶法合成介孔纳米γ-Al2O3,用透射电镜（TEM）、比表面测定（BET）、X射线衍射（XRD）、和N2的吸附-脱附技术、Zetaplus电位测定,对所得的介孔纳米γ-Al2O3进行了表征。考察了介孔纳米γ-Al2O3在静态条件下对La（Ⅲ）的吸附性能。探讨了溶液的初始浓度、pH值、时间和温度对吸附性能的影响。结果表明：介孔纳米γ-Al2O3对La（Ⅲ）有很好的吸附性能,其吸附行为符合Freundlich吸附等温式。     

木质纤维素降解菌系的筛选及其降解特性

旨在为秸秆类木质纤维素沼气工业化奠定科学基础,以滤纸作为纤维素材料对不同发酵原料和发酵时期的沼气池菌系进行驯化和筛选,并研究其中温条件下对麦秸、玉米秸和滤纸的降解特性.采用减重法、分光光度法和蒸馏法分别测定复合菌系在发酵过程中的纤维素降解能力、复合菌系生物量和发酵液中挥发性有机酸.结果显示：发酵原料和发酵时期的菌源纤维素降解能力有较大差异,来自粪便池源的复合菌系在发酵前期纤维素降解力强,而秸秆池源的复合菌系在发酵后期纤维素降解力强.粪源产气稳定期的复合菌系F6的降解能力最强,对纤维素降解能力由高到低依次为滤纸、麦秸和玉米秸.     

TSP问题的智能优化算法研究

智能优化算法比较常见的有模拟退火算法、遗传算法、人工鱼群算法、神经网络算法等。本文主要对前三种算法优化性能进行研究。首先介绍了三种算法的基本原理,然后总结了各自的优缺点并从原理和参数两个方面对三种算法进行了对比分析,以经典NP难题——TSP为例进行了仿真研究给出了未来针对TSP问题的研究重点。     

The association between perceived injunctive norms toward corporal punishment,parenting support,and risk for child physical abuse

The use of corporal punishment (CP) is a strong risk factor for many poor outcomes for children including child maltreatment. The use of CP occurs within social contexts which are important to understand. Although it is known that perceived social norms regarding CP are related to its use, the specific role that a mother’s primary support person plays in influencing attitudes toward and use of CP remains unknown. The current study assessed linkages between maternal perceived social support in parenting and perceived injunctive norms of CP from her primary source of support, with maternal attitudes toward and use of CP. Survey data were collected from female primary caregivers (N = 436) of children age 2 to 7 years (mean age = 3.7) enrolled in Special Supplemental Nutrition Program for Women, Infants and Children (WIC) clinics in Southeastern Louisiana. Most frequently, the biological father of the child (37.9%) and the maternal grandmother of the child (24.2%) were identified as the participant’s primary source of social support in parenting. Perceived injunctive norms of this support person toward CP use were significantly and positively associated with attitudes toward, AOR = 5.97, 95% CI = [4.04, 8.82], and use of CP, AOR = 3.77, 95% CI = [2.55, 5.59]. However, perceived social support was not associated with these outcomes and also did not moderate these associations. Findings suggest that efforts to reduce maternal risk for child physical abuse and use of CP must include the mother’s primary source of social support if they are to be successful.     

Primary physical education subject leadership: along the road from in-house solutions to outsourcing

The modern primary school is a complex institution containing a growing community of individuals and organisations with potentially competing agendas. Within this environment, subject leaders are typically looked upon for advice and guidance within a given subject area such as Physical Education. Yet for those endeavouring to provide Physical Education subject leadership within primary schools, the challenge has grown significantly over the last two decades amidst an ever-changing policy landscape. This paper is for and about primary Physical Education subject leadership; the purpose of which, to plot primary Physical Education's policy journey and explore the implications of reform in shaping the subject leader's role. The paper addresses the current lack of guidance for the subject leader and examines the professional knowledge, skills and experience required to do the role effectively.     

I explain,therefore I learn: Improving students’ assessment literacy and deep learning by teaching

Partnership in higher education emphasises an active role for students in both teaching and learning. This pedagogical culture is likely to make students assessment literate and engage them in deep learning. In this study, Iranian students experiencing learning-by-teaching (LbT) in private language institutes were interviewed to compare their perceptions toward assessment and learning with their counterparts without this experience. Findings show that LbT fosters students’ assessment literacy and deep learning. Results also reveal that by teaching other students, quasi-teachers promote a broader understanding of assessment and grade practices in comparison to other students. Unlike their counterparts, quasi-teachers de-emphasised grades and showed a greater focus on learning. Moreover, explaining the materials to other students provided them with a deeper cognitive process resulting in deeper learning. These results underscore the perceived importance of partnership in higher education.     

Understanding aims and values of science: developments in the junior cycle specifications on nature of science and pre-service science teachers’ views in Ireland

Irish science education is aiming to develop post-primary students’ knowledge of and about science through the introduction of ‘nature of science’ (NOS) in the new junior cycle science specification. This study aimed to investigate pre-service science teachers’ views about a particular aspect of NOS, namely the aims and values of science. Aims and values in relation to science can be considered from epistemic, cognitive, cultural, social, political, moral and ethical perspectives. In this paper, we focus on the epistemic, cognitive and social aims and values of science to provide a broad overview and investigate pre-service science teachers’ understanding of them. Qualitative methods are used to highlight two case studies that provide an in-depth record of how pre-service science teachers interpret aims and values of science. Although the sample is limited in terms of its generalisability to pre-service teacher education at large, the study provides a framework for (a) what to target and investigate about NOS in science education, particularly about aims and values of science, and (b) how pre-service science teachers are likely to make sense of such relatively new curricular goals. Implications for pre-service science teacher education are discussed.