Brane World Cosmic String Interaction

It is shown that brane world gravity produces an attractive force between cosmic strings, in contrast to conventional Einstein gravity. This force is sufficient for stable bound states of Type II strings (which normally repel each other) to form. There is a small separation between the strings, giving them a rope-like structure. At astronomical scales these `cosmic ropes' resemble higher winding number strings, and so all brane world cosmic strings are effectively Type I.Comment: 5 page

Report on the Workshop on Distributed AI

On June 9-11, 22 people gathered at Endicott House for the first workshop on the newly emerging topic of Distributed AI. They came with a wide range of views on the topic, and indeed a wide range of views of what precisely the topic was. In keeping with the spirit of the workshop, this report describing it was prepared in a distributed fashion. Each of the speakers contributed a summary of his comments. Sessions during the workshop included both descriptions of work done or in progress, and group discussions focused on a range of topics. The report reflects the organization, with nine short articles describing research efforts, and four summarizing the informal comments used as the foci for the group discussions.MIT Artificial Intelligence Laborator

Report on the Second Workshop on Distributed AI

On June 24, 1981 twenty-five participants from organizations around the country gathered in MIT's Endicott House for the Second Annual Workshop on Distributed AI. The three-day workshop was designed as an informal meeting, centered mainly around brief research reports presented by each group, along with an invited talk. In keeping with the spirit of the meeting, this report was prepared as a distributed document, with each speaker contributing a summary of his remarks.MIT Artificial Intelligence Laborator

Daze fasteners

A daze fastener system for connecting two or more structural elements wherein the structural elements and fastener parts have substantially different coefficient of thermal expansion physical property characteristics is employed in this invention. By providing frusto-conical abutting surfaces between the structural elements and fastener parts any differences in thermal expansion/contraction between the parts is translated to sliding motion and avoids deleterious thermal stresses in the connection. An essential feature for isotropic homogeneous material connections is that at least two sets of mating surfaces are required wherein each set of mating surfaces has line element extensions that pass through a common point

Collective Bargaining in Municipal Government: How Unionization Impacts Employee's Attitudes, Behaviors, and Values

The purpose of this dissertation is to examine the impact of public sector labor unions on member attitudes, beliefs, and values. I expect that as union members commit to the values of labor organizations they will perceive lower levels of bureaucratic red tape, exhibit higher public service motivation (PSM), and become more satisfied with the nature of public sector work. I devise and test nine hypotheses by analyzing qualitative data generated from interviews with 40 randomly selected union members in two large Kansas cities, and quantitative data collected from a survey instrument distributed to over 300 municipal union members in a single Kansas municipality. The qualitative findings indicate that the union context significantly influences perceptions of bureaucratic red tape and the motives that give rise to PSM. The findings from a series of structural equation models suggest that commitment to union values decreases perceptions of bureaucratic red tape, enhances all four component dimensions of public service motivation, and indirectly increases public sector job satisfaction via bureaucratic red tape and PSM. While this study supports the assertion that labor unions significantly influence the public sector workplace, I rebut the argument that unions primarily decrease organizational performance. Rather unions could increase the performance of public sector organizations by encouraging members to more favorably perceive the work context, promoting member actions designed to benefit others, and facilitating member job satisfaction

Gesture spotting and recognition using salience detection and concatenated hidden markov models

We developed a gesture salience based hand tracking method, and a gesture spotting and recognition method based on concatenated hidden Markov models. A 3-fold cross validation using the ChAirGest development data set with 10 users gives an F1 score of 0.907 and an accurate temporal segmentation rate (ATSR) of 0.923. The average final score is 0.9116. Compared with using the hand joint position from the Kinect SDK, using our hand tracking method gives a 3.7% absolute increase in the recognition F1 score

Toward natural interaction in the real world: real-time gesture recognition

Using a new hand tracking technology capable of tracking 3D hand postures in real-time, we developed a recognition system for continuous natural gestures. By natural gestures, we mean those encountered in spontaneous interaction, rather than a set of artificial gestures chosen to simplify recognition. To date we have achieved 95.6% accuracy on isolated gesture recognition, and 73% recognition rate on continuous gesture recognition, with data from 3 users and twelve gesture classes. We connected our gesture recognition system to Google Earth, enabling real time gestural control of a 3D map. We describe the challenges of signal accuracy and signal interpretation presented by working in a real-world environment, and detail how we overcame them.National Science Foundation (U.S.) (award IIS-1018055)Pfizer Inc.Foxconn Technolog

Analysis and test of superplastically formed titanium hat-stiffened panels under compression

Four hat-stiffened titanium panels with two different stiffener configurations were fabricated by superplastic forming/weld brazing and tested under a moderately heavy compressive load. The panels had the same overall dimensions but differed in the shape of the hat-stiffener webs; three panels had stiffeners with flat webs and the other panel had stiffeners with beaded webs. Analysis indicated that the local buckling strain of the flat stiffener web was considerably lower than the general panel buckling strain or cap buckling strain. The analysis also showed that beading the webs of the hat stiffeners removed them as the critical element for local buckling and improved the buckling strain of the panels. The analytical extensional stiffness and failure loads compared very well with experimental results

Consensus Knowledge Acquisition

We have developed a method and prototype program for assisting two experts in their attempts to construct a single, consensus knowledge base. We show that consensus building can be effectively facilitated by a debugging approach that identifies, explains, and resolves discrepancies in their knowledge. To implement this approach we identify and use recognition and repair procedures for a variety of discrepancies. Examples of this knowledge are illustrated\\ with sample transcripts from CARTER, a system for reconciling two rule-based systems. Implications for resolving other kinds of knowledge representations are also examined