基于个性化学习的线上线下混合教学模式研究--以操作系统课程教学为例

传统的填鸭式教学形式单一,教学效率低下,随着"互联网+"下智慧教学环境的到来,基于个性化学习的线上线下教学应运而生,本文对这种教学形态设计了一种混合教学模式,对其中的个性化学习系统做了分析和设计,以操作系统课程教学为例,对学生信息获取到知识重构及最终达成知识内化的途径进行了分析探讨,教学实践表明:这是一种高效的教学模式。     

“线上+线下”混合式英语课程建设中的学生思辨能力分析

在“线上+线下”混合式教学模式下,学生思辨能力在我国外语教学中显得尤为重要,思辨能力培养的方式、方法也日趋成熟。随着信息时代的飞速发展,越来越多的学者们指出,英语类专业在注重学生听、说、写、读、译等语言和文化知识技能培养的同时,要逐步提高学生自主思考、主动思维的能力,特别是辩证的自主思考问题的能力即思辨能力。随着国家一流专业、一流课程建设推进,混合式教学已成为全国各高校英语专业课程改革的重心,混合式教学“线上”+“线下”各个项目环节的设置,有利于学生提高学习兴趣,凸显个性化学习,实现“学用一体”,提高学生思辨能力。     

A fully spatial personalized differentially private mechanism to provide non-uniform privacy guarantees for spatial databases

Spatial databases are essential to applications in a wide variety of domains. One of the main privacy concerns when answering statistical queries, such as range counting queries, over a spatial database is that an adversary observing changes in query answers may be able to determine whether or not a particular geometric object is present in the database. Differential privacy addresses this concern by guaranteeing that the presence or absence of a geometric object has little effect on query answers. Most of the current differentially private mechanisms for spatial databases ignore the fact that privacy is personal and, thus, provide the same privacy protection for all geometric objects. However, some particular geometric objects may be more sensitive to privacy issues than others, requiring stronger differential privacy guarantees. In this paper, we introduce the concept of spatial personalized differential privacy for spatial databases where different geometric objects have different privacy protection requirements. Also, we present SPDP-PCE, a novel spatial personalized differentially private mechanism to answer range counting queries over spatial databases that fully considers the privacy protection requirements of geometric objects in the underlying geometric space in both steps of noise addition and consistency enforcement. Our experimental results on real datasets demonstrate the effectiveness of SPDP-PCE under various total privacy budgets, query shapes, and privacy level distributions.     

基于深度学习的论文个性化推荐算法

该文基于学术搜索和数据挖掘平台Aminer向用户进行个性化推荐,提出了结合协同过滤推荐和基于内容推荐的混合模型,实验表明该算法可以有效解决新物品的推荐问题,即冷启动问题。其中在基于内容推荐的模型中,融合深度学习的方法,引进了词向量模型,将用户和论文映射到用词向量空间, 并使用WMD(Word Mover Distance)计算相似度。实验表明,与其他基线模型相比该文提出的推荐模型在准确率上显著提高了4%。     

基于知识点与错误率关联的个性化智能组卷模型

大数据环境下的个性化学习模型研究是大规模网络学习环境下的研究热点,本文针对传统的智能组卷策略存在数据训练不足、个性化特点不突出、题库试题知识点分布不均匀等问题,将大数据运用于组卷之中,提出了基于知识点权重与错误率关联的个性化训练模型,优化了抽题的法则并使得个性化特点更精确,在一定程度上有利于学生对薄弱点和盲点的深入理解与消化.本文采用将每章节题目的知识点转化为树形进行管理的方法,并在知识点树中加入知识点错误率元素,来优化基于知识点的抽题结果,研究出适合个人学习情况的个性化模拟练习策略.最后将此新研究模型应用于教学教育系统进行实验研究,研究表明对此关键点的改进更有利于普遍提升学生的整体成绩.     

基于内容和兴趣漂移模型的电影推荐算法研究

基于内容的推荐在用户数据较少的情况下是一种有效的解决冷启动的方法。针对基于内容的推荐算法中,内容相似度计算精度低、用户兴趣漂移等问题,提出一种结合影评内容相似度和长短期兴趣模型来计算电影相似度的推荐方法。算法利用text-rank、word2vec等技术和模型对影评进行关键词抽取和词向量构建,同时基于word2vec训练结果进行电影内容相似度计算,一定程度上解决了近义词、网络词等带来的准确率下降问题;然后基于长短期兴趣漂移模型,统计用户对不同内容属性的偏好权重,并随时间窗口动态计算电影相似度矩阵,缓解了用户兴趣随时间漂移而改的问题;最后根据不同推荐策略获得推荐结果。实验结果证明,该算法比对比方法正确率提高了5%左右,同时兴趣模型提取了用户长短期兴趣标签,在工业界及基于标签的算法等场景中都具有很高的实用价值。     

简化的Slope One在线评分预测算法

个性化推荐系统是大数据时代信息过滤的有效手段,影响推荐系统预测准确性的主要原因之一是数据稀疏性。Slope One评分预测推荐算法采用简单的线性回归模型解决数据稀疏问题,具有易于实现、评分预测速度快的特点,但它在训练阶段生成项目之间评分差的时间和空间消耗大,训练阶段需离线进行。为解决以上问题,提出一种简化的Slope One算法——Simplified Slope One,以两项目历史平均分之差代替项目评分差,来降低算法的时间复杂度和空间复杂度,简化耗时最多的生成项目之间评分差的过程,以有效提高评分数据的利用率,对稀疏数据有更好的适应性。在Movielens数据集上利用按照时间戳排序后划分的测试集进行实验,结果表明Simplified Slope One算法对评分预测的准确性与原Slope One算法接近,但时间复杂度和空间复杂度均低于原Slope One算法,更适合在数据规模增长迅速的大型推荐系统中应用。     

A Robust Wearable Point-of-Care CNT-Based Strain Sensor for Wirelessly Monitoring Throat-Related Illnesses

Point-of-care testing (POC) has the ability to detect chronic and infectious diseases early or at the time of occurrence and provide a state-of-the-art personalized healthcare system. Recently, wearable and flexible sensors have been employed to analyze sweat, glucose, blood, and human skin conditions. However, a flexible sensing system that allows for the real-time monitoring of throat-related illnesses, such as salivary parotid gland swelling caused by flu and mumps, is necessary. Here, for the first time, a wearable, highly flexible, and stretchable piezoresistive sensing patch based on carbon nanotubes (CNTs) is reported, which can record muscle expansion or relaxation in real-time, and thus act as a next-generation POC sensor. The patch offers an excellent gauge factor for in-plane stretching and spatial expansion with low hysteresis. The actual extent of muscle expansion is calculated and the gauge factor for applications entailing volumetric deformations is redefined. Additionally, a bluetooth-low-energy system that tracks muscle activity in real-time and transmits the output signals wirelessly to a smartphone app is utilized. Numerical calculations verify that the low stress and strain lead to excellent mechanical reliability and repeatability. Finally, a dummy muscle is inflated using a pneumatic-based actuator to demonstrate the application of the affixed wearable next-generation POC sensor.     

基于情境感知的用户个性化兴趣建模

用户兴趣模型作为个性化信息推送的基础和核心,其性能的好坏直接关系到个性化推送服务的质量,如何全面了解用户动态的兴趣需求,并及时为用户提供其实时有效的兴趣,是目前用户兴趣模型研究的热点问题。本文主要利用情境感知、用户行为等多维因素建立一种M-C-W用户兴趣模型,提出结合用户显示和隐式兴趣度的计算,挖掘出用户显式兴趣和隐式兴趣的关联性,实现多维动态情境兴趣的结合。通过多角度综合计算用户的兴趣度,实时而准确地表达用户的兴趣爱好。最后,通过实验验证了该模型的有效性和可靠性。