Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

VISDMiner：一个交互式数据挖掘过程可视化系统

针对数据挖掘中挖掘过程不透明以及用户交互少的问题,本文设计并实现了VISDMiner系统。VISDMiner系统将可视化技术和数据挖掘技术结合在一起,提供对挖掘过程中各阶段产生的可视化子结果集的分析。用户可根据自己的领域知识和经验去调整数据挖掘算法模型的参数和可视化模型的参数,促进算法和挖掘分析过程的有效调优。为了处理高维数据集,VISDMiner系统采用一种基于最大信息系数的主成分分析改进算法MIC-PCA,该算法主要是针对传统PCA算法降维能力和分类准确率低的问题进行改进。实验结果表明,VISDMine不仅实现了数据挖掘过程的可视化,还提高了用户对数据挖掘〖JP2〗执行结果的可理解性,其采用的改进的MIC-PCA算法提高了PCA算法的降维能力和分类准确率。     

Power efficient scheme for self localization in wireless sensor networks

With the tremendous applications of the wireless sensor network, self-localization has become one of the challenging subject matter that has gained attention of many researchers in the field of wireless sensor network. Localization is the process of assigning or computing the location of the sensor nodes in a sensor network. As the sensor nodes are deployed randomly, we do not have any knowledge about their location in advance. As a result, this becomes very important that they localize themselves as manual deployment of sensor node is not feasible. Also, in WSN the main problem is the power as the sensor nodes have very limited power source. This paper provides a novel solution for localizing the sensor nodes using controlled power of the beacon nodes such that we will have longer life of the beacon nodes which plays a vital role in the process of localization as it is the only special nodes that has the information about its location when they are deployed such that the remaining ordinary nodes can localize themselves in accordance with these beacon node. We develop a novel model that first finds the distance of the sensor nodes then it finds the location of the unknown sensor nodes in power efficient manner. Our simulation results show the effectiveness of the proposed methodology in terms of controlled and reduced power.     

Detecting and removing specularities in facial images

Specularities often confound algorithms designed to solve computer vision tasks such as image segmentation, object detection, and tracking. These tasks usually require color image segmentation to partition an image into regions, where each region corresponds to a particular material. Due to discontinuities resulting from shadows and specularities, a single material is often segmented into several sub-regions. In this paper, a specularity detection and removal technique is proposed that requires no camera calibration or other a priori information regarding the scene. The approach specifically addresses detecting and removing specularities in facial images. The image is first processed by the Luminance Multi-Scale Retinex [B.V. Funt, K. Barnard, M. Brockington, V. Cardei, Luminance-Based Multi-Scale Retinex, AIC’97, Kyoto, Japan, May 1997]. Second, potential specularities are detected and a wavefront is generated outwards from the peak of the specularity to its boundary or until a material boundary has been reached. Upon attaining the specularity boundary, the wavefront contracts inwards while coloring in the specularity until the latter no longer exists. The third step is discussed in a companion paper [M.D. Levine, J. Bhattacharyya, Removing shadows, Pattern Recognition Letters, 26 (2005) 251–265] where a method for detecting and removing shadows has also been introduced. The approach involves training Support Vector Machines to identify shadow boundaries based on their boundary properties. The latter are used to identify shadowed regions in the image and then assign to them the color of non-shadow neighbors of the same material as the shadow. Based on these three steps, we show that more meaningful color image segmentations can be achieved by compensating for illumination using the Illumination Compensation Method proposed in this paper. It is also demonstrated that the accuracy of facial skin detection improves significantly when this illumination compensation approach is used. Finally, we show how illumination compensation can increase the accuracy of face recognition.     

Biomechanical analysis of materials handling manipulators in short distance transfers of moderate mass objects: joint strength,spine forces and muscular antagonism

Although often suggested as a control measure to alleviate musculoskeletal stresses, the use of mechanical assistance devices (i.e. manipulators) in load transfers has not been extensively studied. Without data describing the biomechanical effects of such devices, justification for decisions regarding implementation of such tools is difficult. An experimental study of two types of mechanical manipulators (articulated arm and overhead hoist) was conducted to determine whether biomechanical stresses, and hence injury risk, would be alleviated. Short distance transfers of loads with moderate mass were performed both manually and with manipulator assistance under a variety of task conditions. Using analysis and output from new dynamic torso models, strength demands at the shoulders and low back, lumbar spine forces, and lumbar muscle antagonism were determined. Strength requirements decreased significantly at both the shoulders and low back when using either manipulator in comparison with similar transfers performed manually. Peak spine compression and anteriorposterior (a-p) shear forces were reduced by about 40% on average, and these reductions were shown to be primarily caused by decreases in hand forces and resultant spinal moments. Two metrics of muscular antagonism were defined, and analysis showed that torso muscle antagonism was largest overall when using the hoist. The results overall suggest that hoist-assisted transfers, although better in reducing spine compression forces, may impose relatively higher demands on coordination and/or stability at extreme heights or with torso twisting motions. The relatively higher strength requirements and spine compression associated with the articulated arm may be a result of the high inertia of the system. Potential benefits of practice and training are discussed, and conclusions regarding implementation of mechanical manipulators are given.     

Modelling Reactive Multimedia: Design and Authoring

Multimedia document authoring is a multifaceted activity, and authoring tools tend to concentrate on a restricted set of the activities involved in the creation of a multimedia artifact. In particular, a distinction may be drawn between the design and the implementation of a multimedia artifact.This paper presents a comparison of three different authoring paradigms, based on the common case study of a simple interactive animation. We present details of its implementation using the three different authoring tools, MCF, Fran and SMIL 2.0, and we discuss the conclusions that may be drawn from our comparison of the three approaches.Simon Thompson is grateful to the British Council for its funding of travel in support of the work reported here.Supported by an individual research grant from NSERC. This author’s research was performed, in part, at LIRMM, Montpellier, France.Supported by an individual research grant from NSERC.     

Standardized task strain and system response times in human-computer interaction

Abstract

Involuntary delays in human-computer interaction, for example, system response times (SRTs) can increase stress. In the present study, 40 college-age subjects were randomly divided into an “incentive” and a “non-incentive” group”. Subjects performed a computer task with SRTs of 0-5, 15, and 4-5 s. Physiological, subjective, and performance data were collected during the task. The computer task was designed to individually set difficulty level (i.e., mental strain), thus standardizing the task for all subjects. By using this procedure, changes resulting from SRT duration can be separated from the effects related to task difficulty. The results indicate that both short and long SRTs produced differential psychophysiological changes consistent with different types of stress responses. Short SRTs resulted in higher autonomic and somatic activity, increased positive self-reported emotional states but poorer performance. Long SRTs resulted in increased electrodermal activity, negative self-reported emotional states and better performance.     

ZIPF'S LAWS IN TEXT MODELING

Zipf's first and second laws define two striking phenomena in literary text. The two laws have applications in various fields of computer science. Recently, the study of continuous speech recognition in artificial intelligence has called for the use of statistical models of text generation. A major issue is the lack of effective and objective evaluation of the models. In this paper, four leading statistical models of text generation are evaluated with respect to Zipf's laws and we identify the Simon-Yule model as a promising approach. A significant implication of the findings for text modeling is also discussed.     

Report on a new OED project: A study of the history of new words in the new OED

The study of the history of new words in theNewOED described in this paper was undertaken in 1986-87, and is based on the material then available. Since then, theNewOED has been finished, and PAT, the inquiry system developed at the University of Waterloo for the investigation of theNewOED data base, has been much altered and improved. Nevertheless, this report should prove useful in indicating the potentiality for analyzing the computerizedNewOED and some of the problems. This project is a study of the ways in which new words are created in English at various periods of time. A chronological dictionary 's created listing words introduced into the language over 50 year increments. These words are then classified by the processes used in forming them to show, in proportional terms, if certain processes are more common at some times than at others.H. M. Logan, Associate Professor, Department of English, University of Waterloo, Waterloo, Ontario, Canada, has written The Dialect of the Middle English Life of St. Katherine (Mouton, 1973), making use of the computer in a study of medieval dialectology. He has also written articles on computer stylistics and literary analysis inCHum, ALLC Journal, Language and Style, College Literature, and on the dictionary inDictionaries.     

一种基于非线性弹簧模型的虚拟手交互新方法

基于虚拟手的交互技术在人机交互和人机工程学测试等应用中发挥着重要的作用。为了实现直观自然、实时准确、接近真实世界中的虚拟手与虚拟物体的交互,并计算出反馈作用力,首先提出了用非线性弹簧模型计算抓取作用力,使虚拟手和虚拟环境之间实现了基于物理的交互;然后将计算结果以视觉渲染的形式反馈给用户,并对仿真的速率做了定量分析,以便使仿真速率可以达到屏幕刷新频率和力反馈刷新频率的要求。实验结果表明,虚拟手不仅可以直观自然地抓取3维虚拟物体,而且和3维物体之间能够进行实时交互,同时可计算出反馈作用力。