Real-time nucleic acid sequence-based amplification (NASBA) using molecular beacon technology (NASBA-beacon) was compared to standard NASBA with postamplification hybridization using electrochemiluminescently labeled probes (NASBA-ECL) for detection of enteroviruses (EV) in 133 cerebrospinal fluid and 27 stool samples. NASBA-ECL and NASBA-beacon were similar in sensitivity, detecting 55 (100%) ...

The IEEE 802.15.4 standard has attracted time-critical applications in wireless sensor networks (WSNs) because of its beaconenabled mode and guaranteed time slots (GTSs). However, the GTS management scheme’s built-in security mechanisms still leave the 802.15.4 MAC vulnerable to attacks. Further, the existing techniques in the literature for securing 802.15.4 either focus on non beacon-enabled ...

Stanford's Space Systems Development Laboratory is developing methods for automated spacecraft health operations. Such operations greatly reduce the need for ground-space communication links and full-time operators. However, new questions emerge about how to supply operators with the spacecraft information that is no longer available. One solution is to introduce a low-bandwidth health beacon a...

This document is disseminated under the sponsorship of the Department of Transportation in the interest of information exchange. The United States Government assumes no liability for its contents or use thereof. 6. Abstract GPS-Squitter is a system concept that merges the capabilities of Automatic Dependent Surveillance (ADS) and the Mode S beacon radar. The result is an integrated concept for ...

IEEE 802.15.4 provides beacon enabled and non-beacon enabled modes. Beacon enabled mode is generally used for energy efficiency. However, the main problem of beacon enabled mode is the fixed superframe structure that leads to inefficient transmission in dynamic traffic conditions. Moreover, 802.15.4 does not provide differential service according to traffic types. In this paper, we propose a Di...

A beacon is a point-like object that can be enabled to exert a magnetic pull on other point-like objects in space. Those objects then move towards the beacon in a greedy fashion until they are either stuck at an obstacle or reach the beacon’s location. Beacons placed inside polyhedra can be used to route point-like objects from one location to another. The notion of beacon-based routing was int...

Stanford's Space Systems Development Laboratory (SSDL) has initiated a new space system technology initiative in order to develop, demonstrate, and validate a beacon monitoring system for spacecraft. This system consists of automated fault detection on board a spacecraft, a state of health beacon signal broadcast by the spacecraft, a ground based monitoring network, and a mission control center...

Wireless transmitters deployed throughout an indoor environment offer the opportunity for accurate location tracking of mobile users. Using radio signal information alone, it is possible to determine the location of a roaming node at close to meter-level accuracy. We are particularly concerned with applications in which the robustness of the locationtracking infrastructure is at stake. For exam...

We describe an innovative implementation of the Shack-Hartmann wave-front sensor that is designed to correct the perspective elongation of a laser guide beacon in adaptive optics. Subapertures are defined by the segments of a deformable mirror rather than by a conventional lenslet array. A bias tilt on each segment separates the beacon images on the sensor's detector. One removes the perspectiv...

We examine a protocol πbeacon that outputs unpredictable and publicly verifiable randomness, meaning that the output is unknown at the time that πbeacon starts, yet everyone can verify that the output is close to uniform after πbeacon terminates. We show that πbeacon can be instantiated via Bitcoin under sensible assumptions; in particular we consider an adversary with an arbitrarily large init...