Insights into ICT capability on a teacher-mentored PGCE course

The study examines the development of ICT capability by associate-trainees on a postgraduate certificate of education course. The course involves the promotion of ICT use during three classroom placements by in-school teacher-mentors. Data for the study were collected by a survey of mentors, four surveys of associate-trainees, and by the collation of associate-trainees' profiles. The study considers the perceived effects upon the trainees development of ICT capability by the course generally and the examples of ICT use provided by teacher-mentors in particular. The study indicates the beneficial effects upon the attitudes of trainees who observe ICT use by teacher-mentors on early school placements, and the coincidence of impoverished ICT use by teacher-mentors on early school placements with restricted use of ICT by associate-trainees on later placements.     

Learning by *ing的教学模式与实践

本文论述了Learning by Doing,Learning by Abstracting,Learning by Analogy,Learning byTeaching以及Learing by Simulating等教学模式。分析了其优点,并介绍了我们将其应用于嵌入式软件开发导论和系统结构等课程的效果。文中尤其强调了Learning by Abstracting的重要性。     

An entropic criterion for minimum uncertainty sensing inrecognition and localization. I. Theoretical and conceptual aspects

A criterion is presented for the automatic selection of a sensor measurement aimed at observing the state of a system which is described both by discrete variables and by continuous ones. The criterion is based on the expected value of the entropy variation associated to the sensor observation. This criterion is then applied to object recognition and localization tasks, in which the observed system is characterized by the object class, represented by a discrete variable, and by the object pose, i.e., position and orientation, represented by a vector of continuous parameters. The proposed criterion also accounts for the information obtained in the case the observed object is missed by the measurement.     

Study of Ardmore,Oklahoma, storm clouds. I. Convective storm cloud initiation and development based on the remote sensing gravity-wave-induced convection

Abstract

Convective instability can be induced by unstable vertical temperature profiles and can be supported by the release of latent heat of water vapour provided by a large quantity of moisture in the air. It can also be released by the presence of gravity waves. Large amplitude gravity waves have been linked to the onset of convective storm systems. In this study, the vertical velocity of convection initiated by gravity waves was investigated. The study of Ardmore, Oklahoma, storms showed that weak convection was initiated by gravity waves having wave periods of 35 min and the convection was enhanced by gravity waves having wave periods of 20 min. Evidence for cloud formation, due to the condensation of water vapour through convection initiated by the gravity waves, was obtained from rapid-scan satellite imagery and radar summaries. In this particular case, the convective motion, initiated and supported by the gravity-wave-induced activity (excluding contributions made by other mechanisms), reached its maximum value about one hour before the production of the funnel clouds. In this study, we did not rule out the contributions made by other mechanisms, such as low-level convergence and others, toward the initiation of convection; however, our main purpose is to discuss the role of gravity waves in wave-induced convection contributing to the fractions of formation and development of severe convective storms.     

On ywo-way,two-tape automata

Two-way, two-tape automata were first considered in Rabin and Scott [1]. We show how surprisingly powerful these machines are by describing some programming techniques that can be implemented on them, and by proving, by means of these techniques, that there exists a universal two-symbol, two-way, two-tape automaton. We then argue that in contradiction to an assertion by Rabin and Scott, the class of sets of pairs of tapes definable by two-way, two-tape automata is not closed under most Boolean operations.This work was supported by the National Science Foundation under grant GJ-596.     

用计量风格学方法考察《水浒传》的作者争议问题——以罗贯中《平妖传》为参照

《水浒传》是独著还是合著、施耐庵和罗贯中是何关系一直存在争议。该文将其作者争议粗略归纳为施耐庵作、罗贯中作、施作罗续、罗作他续、施作罗改五种情况,以罗贯中的《平妖传》为参照,用假设检验、文本聚类、文本分类、波动风格计量等方法,结合对文本内容的分析,考察《水浒传》的写作风格,试图为其作者身份认定提供参考。结果显示,只有罗作他续的可能性大,即前70回为罗贯中所作,后由他人续写,其他四种情况可能性都较小。     

基于多信道Ad Hoc网络的WDSCN的设计

介绍一种基于多信道Ad Hoc网络的思想来实现无线分布式传感/控制网络(WDSCN)。网络节点硬件主要使用UBICOM公司的IP2022作为MCU、Nordic公司的nRF905作为射频芯片。软件以C语言和汇编语言编制,采用多层次结构设计。由于采用多信道的具有自动跳频功能的Ad Hoc网络,该WDSCN具有较强的抗干扰能力,具有较高的实用价值。     

When is it reasonable to implement the discontinuous sliding‐mode controllers instead of the continuous ones? Frequency domain criteria

Professor Utkin proposed an example showing that the amplitude of chattering caused by the presence of parasitic dynamics (stable actuators) in some systems governed by the First‐Order Sliding‐Mode Controller is lower than that produced by the Super‐Twisting Algorithm. This example served to motivate this paper reconsidering the problem of comparison of chattering in systems with stable actuators, and driven by Discontinuous Sliding‐Mode Controllers (DSMCs) and Continuous Sliding‐Mode Controllers (CSMCs). Comparison of chattering produced by DSMC and CSMC taking into account their amplitudes, frequencies, and average power (AP) needed to maintain the system into real‐sliding modes, allowing to conclude the following: (i) for systems with slow actuators, the amplitude of oscillations and AP produced by DSMC be smaller than those caused by CSMC; (ii) for bounded disturbances with fixed Lipschitz constant, there exist sufficiently fast actuators for which the amplitude of oscillations and AP produced by CSMC be smaller than those caused by DSMC.     

微信接警系统

本文提出了微信报警、省上统一接警与三台合一系统联动处警的综合解决方案, 并进行了系统模型研究及可行性实现验证. 微信报警与接警主要是借助微信APP公众号服务, 基于微信开放平台和移动网络通信技术实现, 而联动处警依靠消息推送并以事件触发方式实现. 微信报警简单易用, 易于被多数人接受, 是有效的报警方式.     

So many books

Reviews of "Interface Oriented Design" by Ken Pugh, "Ajax Design Patterns-Creating Web 2.0 Sites with Programming and Usability Patterns" by Michael Mahemoff, "Documenting APIs-Writing Developer Documentation for Java APIs and SDKs" by James F. Bisso and Victoria Maki, "Communicating Design-Developing Web Site Documentation for Design and Planning" by Dan M. Brown, "CSS-The Missing Manual" by David Sawyer McFarland, "Secrets of RSS" Steven Holzner, and ".NET Internationalization-The Developer's Guide to Building Global Windows and Web Applications" by Guy Smith-Ferrier.     

Invariant fitting of planar objects by primitives

The determination of invariant characteristics is an important problem in pattern recognition. Many invariants are known which have been obtained by the method of normalization. In this paper, we introduce a new approach of fitting planar objects by primitives using the method of normalization (e.g., fitting by lines, triangles, rectangles, circles, ellipses, super-quadrics, etc.). Objects and primitives are described by features, for example, by moments. The main advantage is that the normalization process provides us with a canonical frame of the object and the primitive. Therefore, the fit is invariant with respect to the transformation used. By this new method, an analytical fitting of non-analytical objects can be achieved, for example, fitting by polygons. Furthermore, the numerical effort can be reduced drastically by normalizing of the object and the primitive     

基于多属性效用的协同过滤推荐系统

针对基于多标准的协同过滤(MC-CF)推荐系统中用户负担重、超高维问题,提出了基于多属性效用的协同过滤(MAU-CF)推荐系统。首先,依据用户浏览行为挖掘属性权重和属性值效用,构造用户的多属性效用函数,获取用户对项目的隐式评分;其次,采用遗传算法(GA)寻找用户偏好的属性值集合;然后,根据属性值集合中属性权重和属性值效用的相似度,寻找最近邻;最后,根据相似度预测最近邻浏览或购买过的项目对目标用户的效用,向目标用户推荐效用大的项目。通过比较实验发现,相对于MC-CF,MAU-CF挖掘的隐式效用能够替代显式效用,计算维度减少了44.16%,时间消耗减少了27.36%,平均绝对误差(MAE)减少了5.69%,用户满意度提高了13.44%。实验结果表明,MAU-CF推荐系统在减少用户负担和计算维度、提高推荐质量方面比MC-CF推荐系统表现得更优越。     

宽基线视差图像的拼接算法

针对两幅视差图像的拼接问题，提出了一种新算法，即利用Hessian仿射不变检测算子检测出特征区域，利用SIFT特征描述算子提取特征区域特征矢量，根据特征矢量的欧几里德距离来建立图像间的稀疏对应关系；由这些对应点稀疏地确定场景中的一些点，以这些点为顶点建立场景的三角面片近似，再据此将重叠区域重投影生成推扫式成像的中间部分图像。将中间部分推扫式成像图像和原左图像的左半部分以及原右图像的右半部分一起拼接生成大图像。利用实际图像进行的拼接实验表明该算法是一个有效的视差图像拼接算法。     

基于压缩感知和GHM多小波变换的信息隐藏算法

针对基于秘密信息置乱方法等类型的信息隐藏算法不可见性低和抗攻击性弱这一问题,提出了一种基于压缩感知和GHM多小波变换的信息隐藏算法。首先,将载体图像进行一次GHM多小波变换,再对所得到的中间能量区域进行一次小波变换得到HH分量,将HH分量进行奇异值分解;其次,将秘密图像进行小波变换,将得到的小波系数进行压缩感知得到观测矩阵,再对观测矩阵元素进行奇异值分解;最后,利用秘密图像的奇异值替换掉载体图像的奇异值来完成秘密信息的嵌入。实验结果表明,相比两种加密算法,算法不可见性（PSNR值）分别提高5.99%和22.11%;对低通滤波、椒盐噪声、高斯噪声、JPEG压缩等常见攻击具有良好的鲁棒性,相关系数（NC）平均增强了4.11%和11.53%。     

基于复合幂函数修正G1法的商户综合评价

针对多指标综合评价问题中主客观权重相悖时客观权重淹没主观权重的问题,以G1法和客观赋权法为基础,提出了复合幂函数修正G1法的组合赋权模型。首先,建立指标体系并通过G1法确定各指标主观排序和主观初始向量;然后,利用客观赋权法计算各指标客观向量;其次,在不改变主观排序的情况下利用复合幂函数算出主客观结合的综合权重;最后,利用各指标标准化后的值和综合权重计算综合评价值。采用大众点评网的商户数据进行综合评价实验：该模型的均方根误差（RMSE）为3.891,均低于G1-熵权法的8.818和标准差修正G1法的4.752,且覆盖率优于两种对比方法;分别修改主观初始向量和主观排序进行对比实验,修改主观排序的均方根误差为5.430,高于修改主观初始向量的1.17。实验结果表明,该模型得到的评价值与大众点评网官方的评分的一致性较高,且该模型弱化了主观初值对评分结果的影响,体现了主观排序的基础作用。     

Why do media users multitask?: Motives for general,medium-specific,and content-specific types of multitasking

This study examined the major motives for multitasking, and how those motives are related to general, medium-specific, and content-specific types of multitasking. The major motives for multitasking identified in this study are as follows: information, social, enjoyment, efficiency, and habit. Of these motives, general multitasking behavior was predicted by information, efficiency, and habit. In terms of medium-specific types of multitasking, TV-based multitasking was predicted by habit motive, Internet-based multitasking was predicted by information and enjoyment, and mobile-based multitasking was predicted by information motives. In terms of content-specific multitasking, news-related multitasking was predicted by information motives, entertainment-related multitasking was predicted by information and enjoyment motives, and advertising-related multitasking was predicted by information and social motives.     

基于可靠度的循环冗余校验算法

针对循环冗余校验(CRC)准则在信道条件恶化时可能使译码出现较大迭代次数及错误的问题,提出了基于可靠度的迭代停止算法及重传算法。首先,每次迭代后,计算本次译码中间结果的可靠度,通过判断其是否达到阈值来实现迭代的提前结束;然后,将具有最大可靠度的中间结果保存并作为最终译码结果;最后,每次译码后,通过判断最大可靠度是否低于重传阈值来决定是否重传,通过至多3次传输的译码结果来计算最佳译码结果。仿真结果表明,在信噪比低于1.2 dB时,与CRC准则相比,迭代停止算法能在不增加迭代次数的基础上减少1或2个比特错误,重传算法能进一步减少至少2个比特错误,基于可靠度的算法可以实现更少的误比特数和迭代次数。     

Repeated use of online auctions: investigating individual seller motivations

Online auctions, connecting sellers and buyers on the Internet, are a specific type of eMarketplaces. eMarketplaces rely on repeat business in order to build scale, yet little is known about the drivers of repeated use by sellers. Based on an empirical investigation of individual, private sellers, this paper identifies the determinants of their repeated use of online auctions. It demonstrates that repeated use is driven by expectancy concerning performance and effort and by the facilitating conditions provided by auction sites. However, repeated use of online auctions is neither directly motivated by social influences, nor is it moderated by sellers’ demographics.     

两种A／D转换新方法--流水并行式和流水逐次逼近比较式

提出了两种新型模数转换方法。结合时序分析,全面阐明了它们的转换原理。给出了转换时间tc、比特数n和器件内部单元数m三者的数学表达式。对比现行的并行式、逐次逼近比较式和流水式模数转换方法,本文的两种新方法上仍重要的优良特性。基于第一种新方法的流不并行式ADC电路,其m和n的关系优于并行式ADC,并且比流水式ADC易于实现。基于第二种新方法的流水逐次逼近比较式ADC电路,其tc和n的关系优于逐次逼近比较式ADC,并且比流水式ADC易于实现。     

基于高斯混合模型和AdaBoost的夜间车辆检测

针对夜间车辆检测精度相对不高的问题，提出通过构建车头灯对空间几何关系的高斯混合模型（GMM）和采用逆投影车辆样本的AdaBoost分类器准确检测夜间车辆的方法。首先，在交通场景中根据车头灯对的空间位置关系设置逆投影面，通过图像预处理粗定位车灯区域；其次，在逆投影图像下利用车头灯对的空间几何关系构建车灯对的高斯混合模型，初步匹配车头灯对；最后，采用逆投影车辆样本，利用AdaBoost分类器进一步准确检测车辆。实验在3个交通场景的检测结果表明，与原始图像下的AdaBoost方法相比，所提方法的检测率提高了1.93%，漏检率降低了17.83%，误检率降低了27.61%；与D-S （Dempster-Shafer）证据理论方法相比，检测率提高了2.03%，漏检率降低了7.58%，误检率降低了47.51%。所提方法提高了相对检测精度，减少了地面反光和影子等的干扰，满足交通场景中夜间车辆检测的可靠性和准确性的要求。