Space nuclear power systems

Space nuclear power systems are considered for use in those particular spacecraft applications for which nuclear power systems offer unique advantages over solar and/or chemical space power systems. Both isotopic and reactor heated space electrical power units are described in an attempt to illustrate their operating characteristics, spacecraft integration aspects, and factory-to-end of mission operational considerations. The status of technology developments in nuclear power systems is presented. Some projections of those technologies are made to form a basis for the applications of space nuclear power systems to be expected over the next 10-15 years

Musical minds

Comments on the idea that music might be a process of communication between composer and listener

Calling Bulls**t on the Lanham Act: The 2(a) Bar for Immoral, Scandalous, and Disparaging Marks

As the Lanham Act approaches the age of 65, it is a good time to take stock of its application to, and place within, the object and purpose of trademark law. Trademark law seeks to promote fair competition by reducing consumer search costs and preventing confusion in the minds of consumers as to the source of goods and services. However, Section 2(a) of the Lanham Act prevents registration of marks that are “immoral,” “scandalous,” “disparaging,” “deceptive,” or which “create a false association” with persons, institutions, beliefs, or national symbols. The 2(a) bar expands trademark law well beyond its basic goals. While a bar to registration for marks that are deceptive or create a false association is related to the overall object and purpose of trademark law, we argue that the bar to registration for marks that are immoral, scandalous, or disparaging is not, and that the 2(a) bar is — both in definition and application — ineffective, inconsistent, and vague, and that it should be removed from the Lanham Act

In-flight thrust determination on a real-time basis

A real time computer program was implemented on a F-15 jet fighter to monitor in-flight engine performance of a Digital Electronic Engine Controlled (DEES) F-100 engine. The application of two gas generator methods to calculate in-flight thrust real time is described. A comparison was made between the actual results and those predicted by an engine model simulation. The percent difference between the two methods was compared to the predicted uncertainty based on instrumentation and model uncertainty and agreed closely with the results found during altitude facility testing. Data was obtained from acceleration runs of various altitudes at maximum power settings with and without afterburner. Real time in-flight thrust measurement was a major advancement to flight test productivity and was accomplished with no loss in accuracy over previous post flight methods

Revisiting Constraints on Fourth Generation Neutrino Masses

We revisit the current experimental bounds on fourth-generation Majorana neutrino masses, including the effects of right handed neutrinos. Current bounds from LEPII are significantly altered by a global analysis. We show that the current bounds on fourth generation neutrinos decaying to eW and mu W can be reduced to about 80 GeV (from the current bound of 90 GeV), while a neutrino decaying to tau W can be as light as 62.1 GeV. The weakened bound opens up a neutrino decay channel for intermediate mass Higgs, and interesting multi-particle final states for Higgs and fourth generation lepton decays.Comment: 7 pages 1 fi

The fabrication and surface tolerance measurements of the JPL clear aperture microwave antenna

Present ground station microwave antennas of the Deep Space Network are of the symmetric dual reflector (cassegrainian) type. An investigation is being made of alternative high-performance offset antenna designs which have a clear aperture (no reflector or structural blockage) with shaped reflector surfaces. A 1.5-m, 32-GHz clear aperture model was built for experimental studies. The unique processes of fabrication, surface measurement, and alignment are described

Recognition of 3-D Objects from Multiple 2-D Views by a Self-Organizing Neural Architecture

The recognition of 3-D objects from sequences of their 2-D views is modeled by a neural architecture, called VIEWNET that uses View Information Encoded With NETworks. VIEWNET illustrates how several types of noise and varialbility in image data can be progressively removed while incornplcte image features are restored and invariant features are discovered using an appropriately designed cascade of processing stages. VIEWNET first processes 2-D views of 3-D objects using the CORT-X 2 filter, which discounts the illuminant, regularizes and completes figural boundaries, and removes noise from the images. Boundary regularization and cornpletion are achieved by the same mechanisms that suppress image noise. A log-polar transform is taken with respect to the centroid of the resulting figure and then re-centered to achieve 2-D scale and rotation invariance. The invariant images are coarse coded to further reduce noise, reduce foreshortening effects, and increase generalization. These compressed codes are input into a supervised learning system based on the fuzzy ARTMAP algorithm. Recognition categories of 2-D views are learned before evidence from sequences of 2-D view categories is accumulated to improve object recognition. Recognition is studied with noisy and clean images using slow and fast learning. VIEWNET is demonstrated on an MIT Lincoln Laboratory database of 2-D views of jet aircraft with and without additive noise. A recognition rate of 90% is achieved with one 2-D view category and of 98.5% correct with three 2-D view categories.National Science Foundation (IRI 90-24877); Office of Naval Research (N00014-91-J-1309, N00014-91-J-4100, N00014-92-J-0499); Air Force Office of Scientific Research (F9620-92-J-0499, 90-0083

Isolation of 39 polymorphic microsatellite loci and the development of a fluorescently labelled marker set for the Eurasian badger

We have isolated 78 microsatellite loci from the Eurasian badger (Meles meles). Of the 52 loci characterized, 39 were found to be polymorphic. A fluorescently labelled primer set was developed to enable individual-specific 17-locus genotypes to be obtained efficiently

An Overview and Analysis of the Impacts of Extreme Heat on the Aviation Industry

Weather is a common cause of flight delays and cancellations. However, the vast majority of the time when thinking about weather and its effect on aviation, winter conditions such as snow come to mind. Heat is usually one of the last types of weather we associate with airline challenges. Recently, a bomb cyclone made headlines for the disruptions it caused with travel, especially at John F. Kennedy International Airport. Interestingly, the exact opposite of winter weather conditions can cause just as many challenges. During the summer of 2017, a number of flights at various airports such as Phoenix Sky Harbor International were cancelled because the temperature on the runways was physically too hot for the planes to take off. The cancellations themselves only affected smaller, regional aircraft, but high temperatures still significantly affect larger Boeing and Airbus aircraft in the form of weight restrictions that often result in less passengers, less cargo, and potential delays in departure. This research overviews and analyzes the incident that occurred in Phoenix and details how heat significantly affects both small and large aircraft. The study poses several potential solutions including increasing runway lengths, adjusting airport routing, swapping aircraft, adjusting departure times, improving aircraft design, and decreasing on-board weight that can help mitigate the negative effects of extreme heat on the aviation industry