基于KINGOSOFT平台的政治经济学教学模式初探

基于Kingosoft(课程管理系统(CMS))平台,结合大学政治经济学的教学实际,探讨了在Kingosoft平台中的教学模式,为广大教学设计者在Kingosoft平合中更好地设计教学活动提供了一定的理论依据.     

Issues in theorizing mathematics learning and teaching: A contrast between learning through activity and DNR research programs

By continuing a contrast with the DNR research program, begun in Harel and Koichu (2010), I discuss several important issues with respect to teaching and learning mathematics that have emerged from our research program which studies learning that occurs through students’ mathematical activity and indicate issues of complementarity between DNR and our research program. I make distinctions about what we mean by inquiring into the mechanisms of conceptual learning and how it differs from work that elucidates steps in the development of a mathematical concept. I argue that the construct of disequilibrium is neither necessary nor sufficient to explain mathematics conceptual learning. I describe an emerging approach to instruction aimed at particular mathematical understandings that fosters reinvention of mathematical concepts without depending on students’ success solving novel problems.     

On the Properties of the Nonlinear Ship Equations of Motion

Nonlinear ship control systems can be designed by exploiting system properties like passivity and dissipativeness in nonlinear system. The nonlinear ship model is written in a vectorial setting with emphasis placed on matrix properties like positiveness, symmetry and skew-symmetry. As a result of energy conservation the ship dynamics can be considered as two interconnected systems. The first system describes the dissipative motion of the rigid-body (ship) while the second system represents the forces due to potential theory generated by the ambient water particles. It is shown that for a stable ship, both subsystems are passive as well as the interconnected system. For an unstable ship, the ambient water system is input feedforward passive with shortage of passivity and therefore the ship must be stabilized by positive feedback. The structural properties of the nonlinear equations of motion are exploited in the Lyapunov analysis when designing ship control systems.     

基于CDIO模式的高职技师课程开发探讨

CDIO模式为高职院校技师课程体系开发提供了参考模型和标准。本文对照CDIO的模型、大纲、标准和评价对课程开发、课程设计、课程实施和课程评价分别进行分析,特别强调了课程要以具体的三级实践项目贯穿教学,培养学生的实际职业能力。     

Design of computer controlled combustion engines

Globalization and growing new markets, as well as increasing emission and fuel consumption requirements, force the car manufacturers and their suppliers to develop new engine control strategies in shorter time periods. This can mainly be reached by development tools and an integrated hardware and software environment enabling rapid implementation and testing of advanced engine control algorithms.

The structure of a rapid control prototyping (RCP) system is explained, which allows fast measurement signal evaluation, and rapid prototyping of advanced engine control algorithms. A hardware-in-the-loop simulator for diesel engine control design is illustrated, simulation results for a 40 tons truck are presented. Providing efficient engine models for the proposed development tools, a dynamic local linear neural network approach is explained and applied for modelling the NO_x emission characteristics of a 1.9 l direct injection diesel engine. Furthermore the application of a RCP system is exemplified by the application of combustion pressure based closed-loop ignition timing control for a SI engine. Experimental results are shown for a 1.0 l SI engine on a dynamic engine test stand.     

A two-level Iterative Learning Control scheme for the engagement of wet clutches

This paper discusses the application of Iterative Learning Control (ILC) algorithms for the engagement of wet clutches. A two-level control scheme is presented, consisting of a high level ILC-type algorithm which iteratively updates parameterized reference trajectories which are tracked by the low level tracking control. At this low level, two standard ILC controllers are used to first track a pressure reference in the filling phase and afterwards a slip reference in the slip phase of the clutch engagement. The performance and robustness of the presented approach are validated on an experimental test setup. It is shown that both levels are crucial to achieve good engagement quality during normal machine operation. Through the use of this ILC control scheme, it is possible to avoid time-consuming and cumbersome experimental (re)calibrations, which are nowadays used to achieve and maintain good performance despite the complex and time-varying dynamics of wet clutches.     

基于光谱技术的双孢蘑菇新鲜度量化检测技术研究

双孢蘑菇质地柔嫩、营养丰富,具有很好的降血压、降血脂、消炎护肝等多种保健价值,其新鲜度是反映内外部品质的重要指标之一。目前双孢蘑菇新鲜度鉴别大多依据其外观品质变化（褐变）,缺乏精准的量化评价指标与方法,因此提出了以贮藏天数为新鲜度检测的量化指标,并利用近红外光谱技术对双孢蘑菇新鲜度进行检测分析。依据存储天数不同,将双孢蘑菇样本分为1~5组,每组40个样本,依次采集每组双孢蘑菇的近红外光谱数据。针对采集的原始光谱数据,首先选用卷积平滑滤波（SG）与多元散射校正（MSC）消除原始光谱噪声、基线平移以及光散射的影响,并选取399.81~999.81 nm的光谱波段作为数据处理范围;然后分别使用主成分分析（PCA）和连续投影算法（SPA）进行光谱降维和特征波长选择,继而建立极限学习机（ELM）分类模型;同时考虑到ELM模型中初始值对分类准确率影响较大,分别选用粒子群优化算法（PSO）、海鸥优化算法（SOA）对ELM中初始权值及阈值进行寻优,形成PSO-ELM,SOA-ELM优化组合分类模型;最后分别将全光谱、提取主成分以及所选的特征波长｛556.87,445.51,481.15,885.10,802.25,720.90,861.34,909.79,924.44,873.17 nm｝输入到分类模型中,建立不同输入、不同分类模型的双孢菇新鲜度检测模型。最终试验结果表明,当ELM为分类模型,以全光谱、主成分以及特征波长为输入时的预测精度分别为75%,95%,88%;以SPA优选特征波长作为输入的PSO-ELM、SOA-ELM分类模型训练集精度为96.25%,93.25%,预测集精度为92.5%,94%。可知,SPA波长选择算法可以有效降低光谱信息中存在的冗余信息,加快建模效率,同时海鸥优化算法能较好的优化ELM分类模型的初始参数,分类精度较ELM模型提高了6.8%,同时不产生过拟合现象。因此,利用光谱特征可以快速、准确无损的识别双孢蘑菇的新鲜度,研究结果为便携式双孢蘑菇新鲜度快速无损检测设备的开发提供了理论依据。