Expanding the analytical potential of channel locational probability maps using cellular statistics

The planimetric shifts in channel location of large alluvial rivers are a critical component in the creation of diverse structures and functions in riverine habitats. Engineered management schemes must also compensate for this type of channel change to protect resources and maintain navigation channels. The stability of the Lower Mississippi River channel was assessed through an analysis of historical records of channel position produced and archived by the United States Army Corps of Engineers. Channel location was recorded for the years 1765, 1820, 1881, 1915, 1930, 1937, 1960 and 1970. Channel stability was measured by two introduced metrics on a cell‐by‐cell basis: (1) the standard deviation of Euclidean distance to a channel cell for the entire period of record, and (2) the rate of Euclidean distance change between years in the period of record. At a coarse spatial scale, channel instability increased in the downstream direction. The variability of channel stability also increased in the downstream direction. Analysis of this variability identified alternating areas of high and low stability occurring with greater frequency as distance downstream increased. These findings are validated by past studies of channel stability along the Lower Mississippi River. As a result, the proposed metrics provide a consistent, quantitative, efficient and cost‐effective means of identifying areas of channel instability at several spatial scales. Copyright © 2006 John Wiley & Sons, Ltd.     

Monitoring children’s developmental progress using augmented toys and activity recognition

Previous research has established the connection between the way in which children interact with objects and the potential early identification of children with autism. Those findings motivate our own work to develop "smart toys," objects embedded with wireless sensors that are safe and enjoyable for very small children, that allow detailed interaction data to be easily recorded. These sensor-enabled toys provide opportunities for autism research by reducing the effort required to collect and analyze a child’s interactions with objects. In the future, such toys may be a useful part of clinical and in-home assessment tools. In this paper, we discuss the design of a collection of smart toys that can be used to automatically characterize the way in which a child is playing. We use statistical models to provide objective, quantitative measures of object play interactions. We also developed a tool to view rich forms of annotated play data for later analysis. We report the results of recognition experiments on more than fifty play sessions conducted with adults and children as well as discuss the opportunities for using this approach to support video annotation and other applications.     

Mobile phones as computing devices: the viruses are coming!

Understanding existing threats against mobile phones helps us better protect our information and prepare for future dangers. Mobile phones have evolved from their roots as analog walkie-talkies to full-scale Internet-enabled computers. Today, mobile phone handsets are arguably the dominant computer form factor consumers purchase. But having such powerful networked computers leads to a new class of malware: viruses, worms, and trojans specifically designed for the mobile environment. Merely enumerating known attacks doesn't help us understand all possible threats. Instead, we present a taxonomy of attacks against mobile phones that shows known as well as potential attacks.     

Hydrogen permeability of multiphase V-Ti-Ni metallic membranes

Development of advanced hydrogen separation membranes in support of hydrogen production processes such as coal gasification and as front end gas purifiers for fuel cell based system is paramount to the successful implementation of a national hydrogen economy. Current generation metallic hydrogen separation membranes are based on Pd-alloys. Although the technology has proven to be successful, at issue is the high cost of palladium. Evaluation of non-noble metal based dense metallic separation membranes is currently receiving national and international attention. The focal point of the reported work was to evaluate a Group 5A-Ta, Nb, V-based alloy with respect to microstructural features and hydrogen permeability. Electrochemical hydrogen permeation testing of the V-Ti-Ni alloy is reported herein and compared to pure Pd measurements recorded as part of this same study. The V-Ti-Ni was demonstrated to have a steady-state hydrogen permeation rate an order of magnitude higher than the pure Pd material in testing conducted at 22 °C.     

The role of speech input in wearable computing

Speech recognition seems like an attractive input mechanism for wearable computers, and as we saw in this magazine's first issue, several companies are promoting products that use limited speech interfaces for specific tasks. However, we must overcome several challenges to using speech recognition in more general contexts, and interface designers must be wary of applying the technology to situations where speech is inappropriate.     

Thick clients for personal wireless devices

A thin-client approach to mobile computing pushes as many services as possible on a remote server. Technology trends indicate, however, that an easy route to improving thin-client functionality will be to add disk storage, RAM, and a more powerful CPU. Thus, thin clients will rapidly become multipurpose thick clients. With time, users may come to consider their mobile system as their primary general-purpose computing device, maintaining their most-used files on the mobile system and relying on their desktop systems primarily for larger displays, keyboards, and other nonmobile interfaces     

A wearable computer-based American sign Language Recogniser

Modern wearable computer designs package workstation-level performance in systems small enough to be worn as clothing. These machines enable technology to be brought where it is needed most for the handicapped: everyday mobile environments. This paper describes a research effort to make a wearable computer that can recognise (with the possible goal of translating) sentence-level American Sign Language (ASL) using only a baseball cap mounted camera for input. Current accuracy exceeds 97% per word on a 40-word lexicon.