Generalized ordering-search for learning directed probabilistic logical models

Recently, there has been an increasing interest in directed probabilistic logical models and a variety of formalisms for describing such models has been proposed. Although many authors provide high-level arguments to show that in principle models in their formalism can be learned from data, most of the proposed learning algorithms have not yet been studied in detail. We introduce an algorithm, generalized ordering-search, to learn both structure and conditional probability distributions (CPDs) of directed probabilistic logical models. The algorithm is based on the ordering-search algorithm for Bayesian networks. We use relational probability trees as a representation for the CPDs. We present experiments on a genetics domain, blocks world domains and the Cora dataset. Editors: Stephen Muggleton, Ramon Otero, Simon Colton.     

Does attention capacity moderate the effect of driver distraction in older drivers?

With age, a decline in attention capacity may occur and this may impact driving performance especially while distracted. Although the effect of distraction on driving performance of older drivers has been investigated, the moderating effect of attention capacity on driving performance during distraction has not been investigated yet. Therefore, the aim was to investigate whether attention capacity has a moderating effect on older drivers’ driving performance during visual distraction (experiment 1) and cognitive distraction (experiment 2). In a fixed-based driving simulator, older drivers completed a driving task without and with visual distraction (experiment 1, N = 17, mean age 78 years) or cognitive distraction (experiment 2, N = 35, mean age 76 years). Several specific driving measures of varying complexity (i.e., speed, lane keeping, following distance, braking behavior, and crashes) were investigated. In addition to these objective driving measures, subjective measures of workload and driving performance were also included. In experiment 1, crash occurrence increased with visual distraction and was negatively related to attention capacity. In experiment 2, complete stops at stop signs decreased, initiation of braking at pedestrian crossings was later, and crash occurrence increased with cognitive distraction. Interestingly, for a measure of lane keeping (i.e., standard deviation of lateral lane position (SDLP)), effects of both types of distraction were moderated by attention capacity. Despite the decrease of driving performance with distraction, participants estimated their driving performance during distraction as good. These results imply that attention capacity is important for driving. Driver assessment and training programs might therefore focus on attention capacity. Nonetheless, it is crucial to eliminate driver distraction as much as possible given the deterioration of performance on several driving measures in those with low and high attention capacity.     

Characterization and photo-Fenton treatment of used tires leachate

In this study the leachates derived from used tires were firstly characterized by means of the evaluation of their organic matter content. The leachate from tire powder presented a COD value of 508 mg O(2) l(-1) and a TOC of 214 mg Cl (-1). The main identified organic substances were constituents of the rubber structure: benzothiazole derivatives, phthalates, phenolic derivatives, hydrocarbons and fatty acids. The application of photo-Fenton treatment was investigated in order to obtain the maximum organic matter removal. When a solar chamber as light source was used (light intensity=500 Wm(-2)), the best operational conditions were the following: [H(2)O(2)]=3703 mg l(-1), [Fe(2+)]=92.1 mg l(-1), initial pH 2.7-3.0, reaction time=100 min. After the photo-Fenton treatment at optimum conditions, the reached COD and TOC reduction was 64% and 48%, respectively. The main initial organic substances were eliminated after the reaction and no significant by-products were identified. A complementary treatment consisted of coagulation-flocculation carried out with FeCl(3) x 6H(2)O at pH 12 produced a maximum organic matter removal of 43% as COD and 39% as TOC. A combination of photo-Fenton followed by coagulation-flocculation enhanced the organic matter removal: a reduction of 77% of COD and 64% of TOC was attained.     

Viewing 3D TV over two months produces no discernible effects on balance,coordination or eyesight

With the rise in stereoscopic 3D media, there has been concern that viewing stereoscopic 3D (S3D) content could have long-term adverse effects, but little data are available. In the first study to address this, 28 households who did not currently own a 3D TV were given a new TV set, either S3D or 2D. The 116 members of these households all underwent tests of balance, coordination and eyesight, both before they received their new TV set, and after they had owned it for 2 months. We did not detect any changes which appeared to be associated with viewing 3D TV. We conclude that viewing 3D TV does not produce detectable effects on balance, coordination or eyesight over the timescale studied.

Practitioner Summary: Concern has been expressed over possible long-term effects of stereoscopic 3D (S3D). We looked for any changes in vision, balance and coordination associated with normal home S3D TV viewing in the 2 months after first acquiring a 3D TV. We find no evidence of any changes over this timescale.     

Citywide: Supporting Interactive Digital Experiences Across Physical Space

The Citywide project is exploring ways in which technology can provide people with rich and engaging digital experiences as they move through physical space, including historical experiences, performances and games. This paper describes some initial results and experiences with this project based upon two prototype demonstrators. In the first, we describe an application in which a search party explores an archaeological site, uncovering enacted scenes within the virtual world that are of a historical relevance to their particular physical location. In the second, we describe a museum experience where participants explore an outdoors location, hunting for buried virtual artifacts that they then bring back to a museum for a more detailed study. Our demonstrators employ a varied set of devices, including mobile wireless interfaces for locating hotspots of virtual activity when outdoors, to give different experiences of the virtual world depending upon location, task, available equipment and accuracy of tracking. We conclude by discussing some of the potential advantages of using an underlying shared virtual world to support interactive experiences across extended physical settings.     

Agile: a problem-based model of regulatory policy making

We understand regulatory policy problems against the backdrop of existing implementations of a regulatory framework. There are argument schemes for proposing a policy and for criticising a proposal, rooted in a shared understanding that there is an existing regulatory framework which is implemented in social structures in society, yet has problems. The problems with the existing implementations may be attributed either to those implementations or to the constraints imposed by the regulatory framework. In this paper we propose that calls for change of regulatory policy, and case-based and statistical evidence produced in support of policy proposals, are based in model-based problem solving activities. This perspective suggests schemes for a good argument pro or con a policy proposal, while avoiding the problem of backing up claims and evidence on the policy level with a conjectural deep model of the policy domain.     

Automated formal analysis and verification: an overview

This paper provides an overview of various existing approaches to automated formal analysis and verification. The most space is devoted to the approach of model checking, including its basic principles as well as the different techniques that have been proposed for dealing with the state space explosion problem in model checking. This paper, however, includes a brief discussion of theorem proving and static analysis too. All of the discussed approaches are introduced mostly on an informal level, with an attempt to provide the reader with their basic ideas and references to works where more details can be found.     

α粒子微束定点照射--细胞的放射生物学效应及精确性分析

进行微束试验的关键是能够精确地控制照射的粒子数和将粒子准确地射入受照射位点.该研究通过对哥伦比亚大学单粒子微束装置在精确性、准确性以及各项指标的分析发现该装置可精确地控制照射粒子数,精确率为98.4%.同时,它可将α粒子准确地射入受照射位点,束半径为34,达到设计4的标准.在对细胞特定位点如细胞质照射上,粒子击中细胞质至少一个位点的概率为90%,在这一过程中的偶然核击中率,对大多数照射剂量(8个粒子)均小于0.8%.应用该微束装置的放射生物学研究发现单个α粒子仅导致大约20%的致死率,其存活率曲线类似于用常规照射获得的平均粒子存活曲线.诱变试验首次证实单个α粒子在AL细胞的CD59基因位点可诱导出比对照高出3倍数量的诱变子,诱变率随粒子数的增加而增加.这一结果不同于常规照射中,诱变率在高剂量照射后下降的结论.     

A continuous-time delta-sigma modulator for 802.11a/b/g WLAN implemented with a hierarchical bottom-up optimization methodology

This paper presents a 3rd-order continuous-time Delta-Sigma modulator with a resolution of 10 bits for a 10 MHz signal bandwidth. It is designed in a standard 0.18 μm CMOS technology and consumes only 6 mW. After the design/selection of the topologies for the integrators, comparator and D/A converters, optimal sizing of the complete modulator was ensured by using a hierarchical bottom-up, multi-objective evolutionary design methodology. With this methodology, a set of Pareto-optimal modulator designs is generated by using Pareto-optimal performance solutions of the hierarchically decomposed lower-level subblocks. From the generated Pareto-optimal design set, a final optimal design is chosen that complies with the specifications for the 802.11a/b/g WLAN standard and has minimal power consumption.