Mitre Corporation

About: Mitre Corporation is a company organization based out in Bedford, Massachusetts, United States. It is known for research contribution in the topics: Air traffic control & National Airspace System. The organization has 4884 authors who have published 6053 publications receiving 124808 citations. The organization is also known as: Mitre & MITRE.

Progress in the design and realization of an electrically small Huygens source

Abstract: In this paper, we describe our progress to date in the design and realization of an electrically small Huygens source. We begin discussing work by Yaghjian that predicts the maximum directivity achievable with single and dual Huygens sources. Here, we attempt to realize the Huygens source utilizing electrically small electric and magnetic dipoles. Using straight-wire dipole and circular-loop elements, we demonstrate that the directivities predicted by Yaghjian can be achieved with the single and dual Huygens sources. Next, we attempt to realize the Huygens source using recently described, more practical electrically small electric and magnetic dipoles. In free space, these antennas are impedance matched to 50 Ohms and exhibit a quality factor (Q) that approaches the lower bound (the Chu limit). When used in the realization of a Huygens source, these antennas no longer exhibit matched impedances nor low Q's. The limitations that arise in realizing the Huygens source are discussed.

Automatic Reconfiguration for Large-Scale Reliable Storage Systems

Abstract: Byzantine-fault-tolerant replication enhances the availability and reliability of Internet services that store critical state and preserve it despite attacks or software errors. However, existing Byzantine-fault-tolerant storage systems either assume a static set of replicas, or have limitations in how they handle reconfigurations (e.g., in terms of the scalability of the solutions or the consistency levels they provide). This can be problematic in long-lived, large-scale systems where system membership is likely to change during the system lifetime. In this paper, we present a complete solution for dynamically changing system membership in a large-scale Byzantine-fault-tolerant system. We present a service that tracks system membership and periodically notifies other system nodes of membership changes. The membership service runs mostly automatically, to avoid human configuration errors; is itself Byzantine-fault-tolerant and reconfigurable; and provides applications with a sequence of consistent views of the system membership. We demonstrate the utility of this membership service by using it in a novel distributed hash table called dBQS that provides atomic semantics even across changes in replica sets. dBQS is interesting in its own right because its storage algorithms extend existing Byzantine quorum protocols to handle changes in the replica set, and because it differs from previous DHTs by providing Byzantine fault tolerance and offering strong semantics. We implemented the membership service and dBQS. Our results show that the approach works well, in practice: the membership service is able to manage a large system and the cost to change the system membership is low.

Entanglement dynamics in three-qubit X states

Abstract: I explore the entanglement dynamics of a three-qubit system in an initial $X$ state undergoing decoherence including the possible exhibition of entanglement sudden death To quantify entanglement I utilize negativity measures and make use of appropriate entanglement witnesses The negativity results are then extended to $X$ states with an arbitraty number of qubits I also demonstrate nonstandard behavior of the tripartite negativity entanglement metric: its sudden appearance after some amount of decoherence, followed quickly by its disappearance Finally, I solve for a lower bound on the three-qubit $X$-state concurrence, demonstrate when this bound goes to $0$, and outline simplifcations for the calculation of higher-order $X$-state concurrences

Monomolecular electronic device

Abstract: A monomolecular electronic device is provided that includes a molecular diode having at least one barrier insulating group chemically bonded between a pair of molecular ring structures to form a pair of diode sections, at least one dopant group chemically bonded to one of the pair of diode sections, and a molecular gate structure chemically bonded to the one diode section for influencing an intrinsic bias formed by the at least one dopant group. The device thus produced operates as a molecular electronic transistor, exhibiting both switching and power gain. By adding yet another insulating group to the other of the diode sections, an electrical resistance is formed to define an output which represents an inverter or NOT gate function. The NOT gate can be chemically bonded to molecular diode-diode logic structures to form a single molecule that exhibits complex Boolean functions and power gain.

The Relationship Between Trust and Use Choice in Human-Robot Interaction.

Abstract: Objective:To understand the influence of trust on use choice in human-robot interaction via experimental investigation.Background:The general assumption that trusting a robot leads to using that ro...