Multivehicle coverage control for a nonstationary spatiotemporal field

This paper presents a multivehicle sampling algorithm to generate trajectories for nonuniform coverage of a nonstationary spatiotemporal field characterized by spatial and temporal decorrelation scales that vary in space and time, respectively. The sampling algorithm described in this paper uses a nonlinear coordinate transformation that renders the field locally stationary so that existing multivehicle control algorithms can be used to provide uniform coverage. When transformed back to the original coordinates, the sampling trajectories are concentrated in regions of short spatial and temporal decorrelation scales. For fields with coupled spatial statistics, i.e., the spatial decorrelation scales are functions of both spatial dimensions, the coordinate transformation is implemented numerically, whereas for decoupled spatial statistics, the transformation is expressed analytically. We show that the analytical transformation results in vehicle motion that preserves the vehicle sampling speed (which is a measure of vehicle speed scaled by the ratio of the spatial and temporal decorrelation scales), in the original domain; the sampling speed determines the minimum number of vehicles needed to cover a spatiotemporal domain. Theoretical results are illustrated by numerical simulations.     

Deep dyslexia and the right hemisphere hypothesis: Evidence from the U.S.A. and the U.S.S.R.

Discusses the theory that asserts that the residual reading abilities seen in deep dyslexia entirely reflect the operation of an intact right hemisphere reading system rather than a partially disabled left hemisphere reading system. Evidence from an experiment with normal Ss in a report by the present author and colleagues (1983) is presented, which suggests that the right hemisphere contains no lexical entries for abbreviations that can be accessed by visual presentation. Data are presented from studies by K. E. Patterson (1980; see also PA, Vols 63:12203 and 64:10691) on 2 male deep dyslexic's understanding of printed abbreviations, along with observations of a young female deep dyslexic who was tested on understanding of abbreviations and on letter-naming abilities. Considerable sparing of the ability to obtain semantic information from printed abbreviations was evidenced in all 3 Ss. This contrast suggests that the current right hemisphere account of the residual reading abilities seen in deep dyslexia is not a sufficient one and should be modified. (French abstract) (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effective and Efficient Knowledge Base Refinement

This paper presents the STALKER knowledge base refinement system. Like its predecessor KRUST, STALKER proposes many alternative refinements to correct the classification of each wrongly classified example in the training set. However, there are two principal differences between KRUST and STALKER. Firstly, the range of misclassified examples handled by KRUST has been augmented by the introduction of inductive refinement operators. Secondly, STALKER's testing phase has been greatly speeded up by using a Truth Maintenance System (TMS). The resulting system is more effective than other refinement systems because it generates many alternative refinements. At the same time, STALKER is very efficient since KRUST's computationally expensive implementation and testing of refined knowledge bases has been replaced by a TMS-based simulator.     

工程专业团队的管理

当今社会商业竞争激烈,讲求灵活和创新。现代企业因应时势需要,通常采取以团队为基础的工作小组的组织形式。工程专业机构主要由趋向自我领导和对自己工作表现严格要求的专业人员组成,因而指挥一控制模式不再是有效的管理工具。对于这些工程专业团队,我们需要发展新的思路对其进行管理,并加以激励。本文首先简述与职能部门结构相比,跨职能团队结构日趋流行的原因,进而阐述这类团队领导的典型职责,并根据最近的深入研究结果和笔者的经验,揭示一个有效的团队所具备的特征,因其对团队领导能否有效发挥职责至关重要。     

基于滤波的SAR影像去噪方法分析

根据SAR(Synthetic Aperture Radar)影像相干噪声的特点,对现在广泛应用的各种抑制噪声的滤波方法如均值滤波、Frost滤波、增强型Lee滤波、Lee滤波、中值滤波等进行分析,并提出适合本研究区影像的基于小波变换的分量滤波处理去噪方法,利用均值、标准差、平滑指数、PM值、信息熵和平均梯度等评价指标对各种滤波去噪后的影像质量进行评价,并对去噪效果进行对比分析,证明本文所采用的滤波方法对SAR影像噪声有很好的抑制作用,并且较好的保存了图像纹理信息。     

Feature ranking and best feature subset using mutual information

A new algorithm for ranking the input features and obtaining the best feature subset is developed and illustrated in this paper. The asymptotic formula for mutual information and the expectation maximisation (EM) algorithm are used to developing the feature selection algorithm in this paper. We not only consider the dependence between the features and the class, but also measure the dependence among the features. Even for noisy data, this algorithm still works well. An empirical study is carried out in order to compare the proposed algorithm with the current existing algorithms. The proposed algorithm is illustrated by application to a variety of problems.     

Creativity Bento Box: A Physical Resource Pack to Support Interaction in Virtual Space

The Creativity Bento Box is a physical resource pack, designed to support casual social interaction and break taking in an intensive, computer-mediated social activity. It was developed within the Creativity Greenhouse project, which piloted a mechanism to create research proposals and distribute funding at a distance. This involved facilitated phases of collaboration and competition over multiple days of computer-mediated work, where participants communicate and interact through a virtual world. During the iterative development process, the lack of time for socializing, the intense focus on virtual resources, and a lack of time spent away from the screen were reported as negative issues in feedback from participants. This article reports on the development of the Creativity Bento Box and how it helped to address these issues. By providing physical resources that contrasted with the properties of the virtual world, it supported people to socialize and take breaks from their primary activity, allowed them to include physical space and artifacts in their interactions, and provoked moves away from the otherwise intense focus on the computer. The article reflects on the roles of the Bento Box as a gift, in bridging between physical and virtual contexts, its higher suitability during the earlier phases of ideation and group development, and its perception by participants as something “framed.” Through this, we highlight the underexplored potential of using physical, offline resources as a means to solve difficulties in distanced social interactions.     

Software Specification

Abstract

The notion of ‘specification’ is generally held to be crucial to the process of software production and the anchor point for the science of computing. It has, however, no simple, well-defined meaning. There are a variety of interpretations and usages of the term. This paper surveys the field of possibilities, both to display this varietal profusion, and to make the point that no one interpretation has a sound claim to be the best.     

A near‐real time automatic MODIS data processing system

The Moderate Resolution Imaging Spectroradiometer (MODIS) on‐board the Aqua and Terra platforms was designed to improve understanding of global dynamics and processes occurring on the land, in the oceans, and in the lower atmosphere. The UK Dundee Satellite Receiving Station has two X‐band receiving systems capable of capturing direct broadcast data from these spacecraft with a range covering the European shelf‐areas, north‐east Atlantic ocean and the western Mediterranean Sea. Raw data are transferred to the Plymouth Marine Laboratory (PML) and processed in near‐real time into ocean colour and sea‐surface temperature products for the academic community. Data can be used operationally and are made available through the web within 1.5 hours of the satellite overpass time. To our knowledge this is the only such developed system in Europe producing near‐real time MODIS ocean colour products.