Reduced autobiographical memory specificity and rumination in predicting the course of depression.

Reduced autobiographical memory (AM) specificity is a known vulnerability factor for depression. AM specificity was investigated as a predictor of depression with the Autobiographical Memory Test (J. M. G. Williams & K. Broadbent, 1986). When baseline depression scores were partialed, reduced AM specificity to negative cue words predicted higher levels of depression at 7-month follow-up. Once rumination was taken into account by means of the Rumination on Sadness Scale (M. Conway, P. A. R. Csank, S. L. Holm, & C. K. Blake, 2000), AM specificity no longer predicted depression, suggesting that the predictive value of AM specificity observed in previous studies might be--at least partly--explained as an effect of rumination. Further mediation analyses indeed revealed support for rumination as a mediator of the relation between reduced AM specificity and poor outcome of depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A formal relationship between program slicing and partial evaluation

A formal relationship between program slicing and partial evaluation is established. It is proved that for terminating programs, a residual program produced by partial evaluation is semantically equivalent to a conditioned slice. Received May 2002 Revised Octber 2004 and July 2005 Accepted August 2005 by D. J. Cooke     

Using duration models to reduce fragmentation in audio segmentation

We investigate explicit segment duration models in addressing the problem of fragmentation in musical audio segmentation. The resulting probabilistic models are optimised using Markov Chain Monte Carlo methods; in particular, we introduce a modification to Wolff’s algorithm to make it applicable to a segment classification model with an arbitrary duration prior. We apply this to a collection of pop songs, and show experimentally that the generated segmentations suffer much less from fragmentation than those produced by segmentation algorithms based on clustering, and are closer to an expert listener’s annotations, as evaluated by two different performance measures. Editor: Gerhard Widmer     

A suffix tree approach to anti-spam email filtering

We present an approach to email filtering based on the suffix tree data structure. A method for the scoring of emails using the suffix tree is developed and a number of scoring and score normalisation functions are tested. Our results show that the character level representation of emails and classes facilitated by the suffix tree can significantly improve classification accuracy when compared with the currently popular methods, such as naive Bayes. We believe the method can be extended to the classification of documents in other domains. Editor: Tom Fawcett     

The conformal alpha shape filtration

Conformal alpha shapes are a new filtration of the Delaunay triangulation of a finite set of points in ℝ^d. In contrast to (ordinary) alpha shapes the new filtration is parameterized by a local scale parameter instead of the global scale parameter in alpha shapes. The local scale parameter conforms to the local geometry and is motivated from applications and previous algorithms in surface reconstruction. We show how conformal alpha shapes can be used for surface reconstruction of non-uniformly sampled surfaces, which is not possible with alpha shapes.     

Hunting for metamorphic engines

In this paper, we analyze several metamorphic virus generators. We define a similarity index and use it to precisely quantify the degree of metamorphism that each generator produces. Then we present a detector based on hidden Markov models and we consider a simpler detection method based on our similarity index. Both of these techniques detect all of the metamorphic viruses in our test set with extremely high accuracy. In addition, we show that popular commercial virus scanners do not detect the highly metamorphic virus variants in our test set.A talk based on the results in this paper was presented by the authors at Defcon 14, August 5, 2006, Las Vegas, Nevada.     

From MC/DC to RC/DC: formalization and analysis of control-flow testing criteria

This paper describes an approach to the formalization of existing criteria used in computer systems software testing and proposes a new Reinforced Condition/Decision Coverage (RC/DC) criterion. This new criterion has been developed from the well-known Modified Condition/Decision Coverage (MC/DC) criterion and is more suitable for the testing of safety-critical software where MC/DC may not provide adequate assurance. As a formal language for describing the criteria, the Z notation has been selected. Formal definitions in the Z notation for RC/DC, as well as MC/DC and other criteria, are presented. Specific examples of using these criteria for specification-based testing are considered and some features are formally proved. This characterization is helpful in the understanding of different types of testing and also the correct application of a desired testing regime. Received July 2004 Revised November 2005 Accepted November 2005 by J. Derrick, M. Harman and R.M. Herons     

Towards embedded model predictive control for System-on-a-Chip applications

We propose a framework for embedding model predictive control for Systems-on-a-Chip applications. In order to allow the implementation of such a computationally expensive controller on chip, we propose reducing the precision of the microprocessor to the minimum while maintaining near optimal control performance. Taking advantage of the low precision, a logarithmic number system based microprocessor architecture is used, that allows the design of a reduced size processor, providing further energy and computational cost savings. The design parameters for this high-performance embedded controller are chosen using a combination of finite element method simulations and bit-accurate hardware emulations in a number of parametric tests. We provide the methodology for choosing the design parameters for two particular control problems; the temperature regulation in a wafer cross-section geometry, and the control of temperature in a non-isothermal fluid flow problem in a microdevice. Finally, we provide the microprocessor architecture details and estimates for the performance of the resulting embedded model predictive controller.     

IP报文优先级分配的一种方案

IP路由器在处理到达的报文时可有多种排队方式犤1,2犦。文章提出的将用户数据报类型及报文长度综合考虑的多级优先多队列方案,可改善该排队系统的平均时延,而保持原有的QoS。文章同时给出方案的报文平均等待时间的绝对与相对的数量分析。对于报文长度与优先级的关系问题,以往典型的提法是“短报文应优先,以免被长报文拖延”犤5犦,这种提法有其片面性。实际上,短报文应优先,以改善排队系统的系统平均时延;而如果按报文长度赋予优先级,短报文优先,则可达到最佳系统平均时延。