The search for new physics by the measurement of the 4-jet cross section at LHC and FNAL

We investigate the possibility to look for new physics by the measurement of the 4-jet cross section at LHC and FNAL. In particular, we consider the model with scalar colour octet and the supersymmetric model with R-parity violation. In both models pair produced new particles decay into 2 jets thus leading to 4-jet events. Therefore, the measurement of the distributions of 4-jet differential cross section on the invariant dijet masses allows to look for new physics. The main background comes from standard QCD 4-jet events. We find that at LHC it would be possible to discover scalar colour particles with masses up to 900 Gev and for FNAL the corresponding bound is 175 Gev.Comment: 14 pages, late

Development of a knowledge acquisition tool for an expert system flight status monitor

Two of the main issues in artificial intelligence today are knowledge acquisition dion and knowledge representation. The Dryden Flight Research Facility of NASA's Ames Research Center is presently involved in the design and implementation of an expert system flight status monitor that will provide expertise and knowledge to aid the flight systems engineer in monitoring today's advanced high-performance aircraft. The flight status monitor can be divided into two sections: the expert system itself and the knowledge acquisition tool. The knowledge acquisition tool, the means it uses to extract knowledge from the domain expert, and how that knowledge is represented for computer use is discussed. An actual aircraft system has been codified by this tool with great success. Future real-time use of the expert system has been facilitated by using the knowledge acquisition tool to easily generate a logically consistent and complete knowledge base

Rapid prototyping facility for flight research in artificial-intelligence-based flight systems concepts

The Dryden Flight Research Facility of the NASA Ames Research Facility of the NASA Ames Research Center is developing a rapid prototyping facility for flight research in flight systems concepts that are based on artificial intelligence (AI). The facility will include real-time high-fidelity aircraft simulators, conventional and symbolic processors, and a high-performance research aircraft specially modified to accept commands from the ground-based AI computers. This facility is being developed as part of the NASA-DARPA automated wingman program. This document discusses the need for flight research and for a national flight research facility for the rapid prototyping of AI-based avionics systems and the NASA response to those needs

Description of an experimental expert system flight status monitor

This paper describes an experimental version of an expert system flight status monitor being developed at the Dryden Flight Research Facility of the NASA Ames Research Center. This experimental expert system flight status monitor (ESSFSM) is supported by a specialized knowledge acquisition tool that provides the user with a powerful and easy-to-use documentation and rule construction tool. The EESFSM is designed to be a testbed for concepts in rules, inference mechanisms, and knowledge structures to be used in a real-time expert system flight status monitor that will monitor the health and status of the flight control system of state-of-the-art, high-performance, research aircraft

Design of an expert-system flight status monitor

The modern advanced avionics in new high-performance aircraft strains the capability of current technology to safely monitor these systems for flight test prior to their generalized use. New techniques are needed to improve the ability of systems engineers to understand and analyze complex systems in the limited time available during crucial periods of the flight test. The Dryden Flight Research Facility of NASA's Ames Research Center is involved in the design and implementation of an expert system to provide expertise and knowledge to aid the flight systems engineer. The need for new techniques in monitoring flight systems and the conceptual design of an expert-system flight status monitor is discussed. The status of the current project and its goals are described

Expert systems development and application

Current research in the application of expert systems to problems in the flight research environment is discussed. In what is anticipated to be a broad research area, a real time expert system flight status monitor has been identified as the initial project. This real time expert system flight status monitor is described in terms of concept, application, development, and schedule

An engineering approach to the use of expert systems technology in avionics applications

The concept of using a knowledge compiler to transform the knowledge base and inference mechanism of an expert system into a conventional program is presented. The need to accommodate real-time systems requirements in applications such as embedded avionics is outlined. Expert systems and a brief comparison of expert systems and conventional programs are reviewed. Avionics applications of expert systems are discussed before the discussions of applying the proposed concept to example systems using forward and backward chaining

Flow control in S-Shaped Air Intake using Zero-Net-Mass-Flow

Flow control using zero-net-mass-flow jets in a twodimensional model of an S-Shaped air intake diffuser was investigated. Experiments were conducted in a channel flow facility at a Reynolds number of Re = 8×104 with particular image velocimetry measurements in the symmetry plane of the duct. In the natural configuration, separation of the boundary layer occurs in a region of the duct with a high degree of curvature. A stability analysis of the wall normal profile at the location of the applied control is presented and estimates the most effective frequency of the actuator. Time-averaged velocity fields show total reattachment of the boundary layer using active flow control

Observations of the Habits of \u3ci\u3eCorthylus Punctatissimus\u3c/i\u3e (Coleoptera: Scolytidae) Infesting Maple Saplings in Central Michigan

Corthylus punctatissimus, the pitted ambrosia beetle, infested and killed maple saplings that were 3-12 years of age with a basal diameter of 4-14 mm. The habits of the parental pair of adults are described. The beetles construct a spiral gallery system with about five egg niches per host. Half the brood reaches adult stage during the summer with a sex ratio of 1:1. No relationship was found between the number of niches, length of gallery system, or diameter of stem

High-frequency spin valve effect in ferromagnet-semiconductor-ferromagnet structure based on precession of injected spins

New mechanism of magnetoresistance, based on tunneling-emission of spin polarized electrons from ferromagnets (FM) into semiconductors (S) and precession of electron spin in the semiconductor layer under external magnetic field, is described. The FM-S-FM structure is considered, which includes very thin heavily doped (delta-doped) layers at FM-S interfaces. At certain parameters the structure is highly sensitive at room-temperature to variations of the field with frequencies up to 100 GHz. The current oscillates with the field, and its relative amplitude is determined only by the spin polarizations of FM-S junctions at relatively large bias voltage.Comment: 5 pages, 2 figures, (v2) new plot with a dependence of current J on magnetic field H added in Fig.2 (top panel), minor amendments in the text; (v3) minor typos corrected. To appear in Phys. Rev. Letter