Methods for measuring waves and winds from a Wave Glider autonomous surface vehicle (ASV) are described and evaluated. The wave method utilizes the frequency spectra of orbital velocities measured by GPS, and the wind stress method utilizes the frequency spectra of turbulent wind fluctuations measured by an ultrasonic anemometer. Both methods evaluate contaminations from vehicle motion. The methods were evaluated with 68 days of data over a full range of open ocean conditions, in which wave heights varied from 1 to 8 m and wind speeds varied from 1 to 17 m s−1. Reference data were collected using additional sensors on board the vehicle. For the waves method, several additional datasets are included that use independently moored Datawell Waverider buoys as reference data. Bulk wave parameters are determined within 5% error with biases of less than 5%. Wind stress is determined within 4% error with 1% bias. Wave directional spectra also compare well, although the Wave Glider results have more spread at low frequencies.

This article reports on the design, development, and validation of advanced prototype 2 MVA generation equipment [i.e., naval package (NP)] for a shipboard medium-voltage dc integrated power system (MVDC IPS). The generation equipment is based on an ultrahigh-speed 22,500-r/min 12-phase alternator, which feeds an ac/dc power electronics converter comprising four diode rectifiers and four insulated-gate bipolar transistor (IGBT) choppers. The prototype realization constitutes a follow-up of a previous NP version employing a wound-field 6,300-r/min alternator feeding noncontrolled ac/dc converters. The major technical challenges faced in the design and development of the advanced NP prototype are outlined in this article, taking the previous lower-speed version as a technology reference. The system performance, as determined by the testing campaign, and lessons learned for future studies are addressed

This paper reports on the design, development and validation of an advanced prototype 2MVA generation equipment (Naval Package) for a shipboard Medium-Voltage DC integrated power system. The generation equipment is based on a ultra-high-speed 22500-rpm 12-phase alternator which feeds an AC/DC power electronics converter composed of four diode rectifiers and four IGBT choppers. The prototype realization constitutes a follow-up of a previous Naval Package version employing a wound-field 6300-rpm alternator feeding non-controlled AC/DC converters. The major technical challenges faced in the design and development of the advanced Naval Package prototype are outlined in this paper taking the previous lower-speed version as a technology reference. The system performance highlighted by the testing campaign are finally addressed along with the lesson learnt to be capitalized for future developments.

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The concept of distributed air-to-air separation assurance envisions aircraft detecting and resolving conflicts autonomously without the need for a ground based air traffic service provider. Current automated conflict resolution algorithms that assume instantaneous heading changes without consideration of turn dynamics can result in unintentional loss of separation. A simulation of distributed conflict resolutions is used to evaluate a recently developed algorithm that implements realistic turn dynamics, i.e., without assuming instantaneous heading changes. In particular, the algorithm incorporates turn dynamics to resolve pair-wise, horizontal conflicts at close ranges. Examples of resolution trajectories generated by the separation assurance algorithm are shown. Data on the performance of this algorithm is extracted from the simulation. More importantly, analysis of these results indicates a need for coordination and communication between conflicting aircraft in order to guarantee a high level of safety in a distributed air-to-air separation assurance environment. = Minimum distance achieved during the entire maneuver. This may occur during the turn, at the end of the turn, or in the straight-line segment beginning at the end of the turn