27,600 research outputs found
Ground terminal expert (GTEX). Part 2: Expert system diagnostics for a 30/20 Gigahertz satellite transponder
A research effort was undertaken to investigate how expert system technology could be applied to a satellite communications system. The focus of the expert system is the satellite earth station. A proof of concept expert system called the Ground Terminal Expert (GTEX) was developed at the University of Akron in collaboration with the NASA Lewis Research Center. With the increasing demand for satellite earth stations, maintenance is becoming a vital issue. Vendors of such systems will be looking for cost effective means of maintaining such systems. The objective of GTEX is to aid in diagnosis of faults occurring with the digital earth station. GTEX was developed on a personal computer using the Automated Reasoning Tool for Information Management (ART-IM) developed by the Inference Corporation. Developed for the Phase 2 digital earth station, GTEX is a part of the Systems Integration Test and Evaluation (SITE) facility located at the NASA Lewis Research Center
Patent Damage Strategies and the Enterprise License: Constructive Notice, Actual Notice, No Notice
For the patent owner, early provision of patent notice can help maximize recoverable infringement damages during subsequent litigation. This iBrief recognizes a growing trend of infringement suits predicated on patented enterprise software technology, and analyzes application of patent notice principles against industry convention. This iBrief examines the licensing paradigm of enterprise software and questions whether mechanical compliance with the marking statute should qualify as constructive notice. Borrowing from analogous Federal Circuit principles, this iBrief concludes by proposing alternate notice theories that would empower patentees to seek increased remedies consistent with industry reality, case law, and fundamental statutory purpose
Application of fracture mechanics and half-cycle method to the prediction of fatigue life of B-52 aircraft pylon components
Stress intensity levels at various parts of the NASA B-52 carrier aircraft pylon were examined for the case when the pylon store was the space shuttle solid rocket booster drop test vehicle. Eight critical stress points were selected for the pylon fatigue analysis. Using fracture mechanics and the half-cycle theory (directly or indirectly) for the calculations of fatigue-crack growth ,the remaining fatigue life (number of flights left) was estimated for each critical part. It was found that the two rear hooks had relatively short fatigue life and that the front hook had the shortest fatigue life of all the parts analyzed. The rest of the pylon parts were found to be noncritical because of their extremely long fatigue life associated with the low operational stress levels
The Cost of Sybils, Credible Commitments, and False-Name Proof Mechanisms
Consider a mechanism that cannot observe how many players there are directly,
but instead must rely on their self-reports to know how many are participating.
Suppose the players can create new identities to report to the auctioneer at
some cost . The usual mechanism design paradigm is equivalent to implicitly
assuming that is infinity for all players, while the usual Sybil attacks
literature is that it is zero or finite for one player (the attacker) and
infinity for everyone else (the 'honest' players). The false-name proof
literature largely assumes the cost to be 0. We consider a model with variable
costs that unifies these disparate streams.
A paradigmatic normal form game can be extended into a Sybil game by having
the action space by the product of the feasible set of identities to create
action where each player chooses how many players to present as in the game and
their actions in the original normal form game. A mechanism is (dominant)
false-name proof if it is (dominant) incentive-compatible for all the players
to self-report as at most one identity. We study mechanisms proposed in the
literature motivated by settings where anonymity and self-identification are
the norms, and show conditions under which they are not Sybil-proof. We
characterize a class of dominant Sybil-proof mechanisms for reward sharing and
show that they achieve the efficiency upper bound. We consider the extension
when agents can credibly commit to the strategy of their sybils and show how
this can break mechanisms that would otherwise be false-name proof
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High-Performance Integrated Window and Façade Solutions for California
The researchers developed a new generation of high-performance façade systems and supporting design and management tools to support industry in meeting California’s greenhouse gas reduction targets, reduce energy consumption, and enable an adaptable response to minimize real-time demands on the electricity grid. The project resulted in five outcomes: (1) The research team developed an R-5, 1-inch thick, triplepane, insulating glass unit with a novel low-conductance aluminum frame. This technology can help significantly reduce residential cooling and heating loads, particularly during the evening. (2) The team developed a prototype of a windowintegrated local ventilation and energy recovery device that provides clean, dry fresh air through the façade with minimal energy requirements. (3) A daylight-redirecting louver system was prototyped to redirect sunlight 15–40 feet from the window. Simulations estimated that lighting energy use could be reduced by 35–54 percent without glare. (4) A control system incorporating physics-based equations and a mathematical solver was prototyped and field tested to demonstrate feasibility. Simulations estimated that total electricity costs could be reduced by 9-28 percent on sunny summer days through adaptive control of operable shading and daylighting components and the thermostat compared to state-of-the-art automatic façade controls in commercial building perimeter zones. (5) Supporting models and tools needed by industry for technology R&D and market transformation activities were validated. Attaining California’s clean energy goals require making a fundamental shift from today’s ad-hoc assemblages of static components to turnkey, intelligent, responsive, integrated building façade systems. These systems offered significant reductions in energy use, peak demand, and operating cost in California
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