A PERTURBATION­BASED APPROACH FOR MULTI­CLASSIFIER SYSTEM DESIGN

Microsoft, Motorola, Siemens, Hitachi, IAPR, NICI, IUF This paper presents a perturbation­based approach useful to select the best combination method for a multi­classifier system. The basic idea is to simulate small variations in the performance of the set of classifiers and to evaluate to what extent they influence the performance of the combined classifier. In the experimental phase, the Behavioural Knowledge Space and the Dempster­Shafer combination methods have been considered. The experimental results, carried out in the field of hand­written numeral recognition, demonstrate the effectiveness of the new approach

The Trigger System of the ARGO-YBJ detector

The ARGO-YBJ experiment has been designed to detect air shower events over a large size scale and with an energy threshold of a few hundreds GeV. The building blocks of the ARGO-YBJ detector are single-gap Resistive Plate Counters (RPCs). The trigger logic selects the events on the basis of their hit multiplicity. Inclusive triggers as well as dedicated triggers for specific physics channels or calibration purposes have been developed. This paper describes the architecture and the main features of the trigger system.Comment: 4 pages, to be published in the Proceedings of the 28th International Cosmic Ray Conference (Tsukuba, Japan 2003

ZONING DESIGN FOR HAND­WRITTEN NUMERAL RECOGNITION

Microsoft, Motorola, Siemens, Hitachi, IAPR, NICI, IUF In the field of Optical Character Recognition (OCR), zoning is used to extract topological information from patterns. In this paper zoning is considered as the result of an optimisation problem and a new technique is presented for automatic zoning. More precisely, local analysis of feature distribution based on Shannon's entropy estimation is performed to determine "core" zones of patterns. An iterative region­growing procedure is applied on the "core" zones to determine the final zoning

The 1999 Flood of the Century: Extraordinary Hydrometeorological Event or Human-Induced Catastrophe?

In 1999 the effects of Floyd, Dennis, and Irene caused unprecedented flooding, but was this a natural event or a human disaster? The researchers examined photographs of the effects of Hurricane Floyd and some other floods to compare flood stage. They also looked at drainage basins and census data to examine land use changes and how they have affected the drainage basins. Rainfall data at 21 stations were collected during Hurricane Floyd. Hurricane Dennis, which dumped 10–20 inches of rainfall in the Greenville area, saturated the soils, but did not cause major flooding. The three-week period including Hurricanes Dennis and Floyd was as much as 85% of annual rainfall. At these stations, there were 200- and 500-year recurrence intervals, which means this was an extreme event. Using parametric and non-parametric statistics they find a significant trend in annual mean discharge and flow, but not an association with human activities. There was no trend through time. In comparison to Mississippi River flooding, they found that floods are self-similar events and recurrence intervals are subject to a large amount of uncertainty. The largest events drown out human impacts since there is limited storage capacity of wetlands. During a period of rapid urbanization, there was little change in the stream flow at the scale of watersheds. Extreme precipitation plus the sequencing of storms means that there was not a difference due to human land use issues