Artificial Intelligence

Contains a report on a research project.National Science Foundation (Grant G-16526)National Institutes of Health (Grant MH-04737-02)M.I.T. Computation Cente

A limited speech recognition system 2 Final report

Limited speech recognition system for computer voice lin

A limited speech recognition system Final report

Systems analysis, recognition algorithm, and design of limited speech recognition syste

The Voluntary Adjustment of Railroad Obligations

Automatic memory management techniques eliminate many programming errors that are both hard to find and to correct. However, these techniques are not yet used in embedded systems with hard realtime applications. The reason is that current methods for automatic memory management have a number of drawbacks. The two major ones are: (1) not being able to always guarantee short real-time deadlines and (2) using large amounts of extra memory. Memory is usually a scarce resource in embedded applications. In this paper we present a new technique, Real-Time Reference Counting (RTRC) that overcomes the current problems and makes automatic memory management attractive also for hard real-time applications. The main contribution of RTRC is that often all memory can be used to store live objects. This should be compared to a memory overhead of about 500% for garbage collectors based on copying techniques and about 50% for garbage collectors based on mark-and-sweep techniques

Monitoring functional arm movement for home-based therapy after stroke.

The goal of this project is to develop a means for individuals with stroke to practice arm movement therapy at home with remote monitoring. We previously developed a Web-based system for repetitive movement training (Java Therapy). This paper describes a new input device for the system that measures and assists in naturalistic arm movement, as well as software enhancements. The new input device is an instrumented, adult-sized version of Wilmington robotic exoskeleton (WREX), which is a five degrees-of-freedom orthosis that counterbalances the weight of the arm using elastic bands. To test the ability of the new device (Training-WREX or "T-WREX") to measure and assist in functional arm movements, we measured five chronic stroke subjects' movement ability while wearing the orthosis without gravity balance compared to wearing the orthosis with gravity balance. T-WREX's gravity balance function improved a clinical measure of arm movement (Fugl-Meyer Score), range of motion of reaching movements, and accuracy of drawing movements. Coupled with an enhanced version of Java Therapy, T-WREX will thus provide a means to assist functional arm movement training at home, either over the Web in real-time, or stand-alone with periodic communication with a remote site

Artificial Intelligence

Contains research objectives and reports on five research projects.Computation Center, M.I.T

Rare Variant Analysis of Human and Rodent Obesity Genes in Individuals with Severe Childhood Obesity

Obesity is a genetically heterogeneous disorder. Using targeted and whole-exome sequencing, we studied 32 human and 87 rodent obesity genes in 2,548 severely obese children and 1,117 controls. We identified 52 variants contributing to obesity in 2% of cases including multiple novel variants in GNAS, which were sometimes found with accelerated growth rather than short stature as described previously. Nominally significant associations were found for rare functional variants in BBS1, BBS9, GNAS, MKKS, CLOCK and ANGPTL6. The p.S284X variant in ANGPTL6 drives the association signal (rs201622589, MAF∼0.1%, odds ratio = 10.13, p-value = 0.042) and results in complete loss of secretion in cells. Further analysis including additional case-control studies and population controls (N = 260,642) did not support association of this variant with obesity (odds ratio = 2.34, p-value = 2.59 × 10 -3 ), highlighting the challenges of testing rare variant associations and the need for very large sample sizes. Further validation in cohorts with severe obesity and engineering the variants in model organisms will be needed to explore whether human variants in ANGPTL6 and other genes that lead to obesity when deleted in mice, do contribute to obesity. Such studies may yield druggable targets for weight loss therapies