Conceptual dead weight device to provide pressure calibration

Dead weight testing device uses a common force plane piston manometer to set accurate gage pressure in pounds per square inch. An additional piston gage easily adapts the device for absolute pressure calibration

Combustion of velcro in low gravity

An experimental program was conducted to investigate the low gravity burning characteristics on nylon and Nomex Velcro fastening tapes in an atmosphere of 30-percent oxygen, 70-percent nitrogen at a 70-kPa pressure. The tests were conducted using the NASA Lewis Research Center Zero Gravity Facility. The test results, as documented by high-speed cameras, indicate that both nylon and Nomex burn in low gravity for the full 5.18 sec test time but that Nomex burns less vigorously than nylon. Nylon melts as it burns, whereas Nomex forms a solid char. Nylon also sputters burning droplets as it burns. Thus, from these limited tests, it appears that Nomex Velcro is less hazardous than nylon Velcro for spacecraft applications. The results also show that residual gas velocities, and by analogy spacecraft air circulation, can enhance the low-gravity combustion

Development of SSB/DSB auxiliary time division multiplexer and demultiplexer Final report, 14 Jun. 1967 - 19 Feb. 1968

Design and performance of single sideband-double sideband auxiliary time division multiplexer prototype and demultiplexer breadboard mode

The Ontological Basis of Strong Artificial Life

This article concerns the claim that it is possible to create living organisms, not merely models that represent organisms, simply by programming computers ("virtual" strong alife). I ask what sort of things these computer-generated organisms are supposed to be (where are they, and what are they made of?). I consider four possible answers to this question: (a) The organisms are abstract complexes of pure information; (b) they are material objects made of bits of computer hardware; (c) they are physical processes going on inside the computer; and (d) they are denizens of an entire artificial world, different from our own, that the programmer creates. I argue that (a) could not be right, that (c) collapses into (b), and that (d) would make strong alife either absurd or uninteresting. Thus, "virtual" strong alife amounts to the claim that, by programming a computer, one can literally bring bits of its hardware to life

Advanced thin film thermocouples

The fabrication, materials characterization, and performance of thin film platinum rhodium thermocouples on gas turbine alloys was investigated. The materials chosen for the study were the turbine blade alloy systems MAR M200+Hf with NiCoCrAlY and FeCrAlY coatings, and vane alloy systems MAR M509 with FeCrAlY. Research was focussed on making improvements in the problem areas of coating substrate stability, adhesion, and insulation reliability and durability. Diffusion profiles between the substrate and coating with and without barrier coatings of Al2O3 are reported. The relationships between fabrication parameters of thermal oxidation and sputtering of the insulator and its characterization and performance are described. The best thin film thermocouples were fabricated with the NiCoCrAlY coatings which were thermally oxidized and sputter coated with Al2O3

The Attack-and-Defense Group Contests: Best-shot versus Weakest-link

This study analyzes a group contest in which one group (defenders) follows a weakest-link whereas the other group (attackers) follows a best-shot impact function. We fully characterize the Nash and coalition-proof equilibria and show that with symmetric valuation the coalition-proof equilibrium is unique up to the permutation of the identity of the active player in the attacker group. With asymmetric valuation it is always an equilibrium for one of the highest valuation players to be active; it may also be the case that the highest valuation players in the attacker group free-ride completely on a group-member with a lower valuation. However, in any equilibrium, only one player in the attacker group is active, whereas all the players in the defender group are active and exert the same effort. We also characterize the Nash and coalition-proof equilibria for the case in which one group follows either a best-shot or a weakest-link but the other group follows an additive impact function

Acroneuria lycorias (Boreal Stonefly, Plecoptera: Perlidae) Emergence Behaviors Discovered in Pinus strobus Canopy

Species of Plecoptera, or stoneflies, are known to use vertical emergence supports, and researchers believe many species of Plecoptera exploit arboreal habitats during emergence. However, the exact nature of these arboreal behaviors has largely remained a mystery. While exploring the habitat potential of Pinus strobus (L.) (Eastern White Pine) canopies in northern Wisconsin we observed Acroneuria lycorias (Newman) (Boreal Stonefly, Plecoptera: Perlidae) exuviae at heights as high as 12m (observations at 6.6, 9, 9.5, and 12m). Most A. lycorias exuviae appeared to have a strong preference for emergence sites at the underside or base of branches similar to some Odonate species. We also observed A. lycorias, adults climbing upwards along the main stem, post-emergence, to heights up to 22m. To our knowledge, these heights represent the greatest heights ever documented for A. lycorias adults and exuviae, or any Plecopteran species. While other researchers have speculated that A. lycorias uses arboreal habitats during emergence, these behaviors were considered almost impossible to describe. Our observations provide us with new insights into Plecopteran emergence behaviors, especially for this species. We propose three alternative hypotheses that may explain these unique emergence behaviors

Devil's Staircase and Disordering Transitions in Sliding Vortices and Wigner Crystals on Random Substrates with Transverse Driving

Using numerical simulations we show that, in the presence of random quenched disorder, sliding superconducting vortices and Wigner crystals pass through a variety of dynamical phases when an additional transverse driving force is applied. If the disorder is weak, the driven particles form a moving lattice and the transverse response shows a devil's staircase structure as the net driving force vector locks with the symmetry directions of the moving lattice, in agreement with the predictions of Le Doussal and Giamarchi. For strong disorder, and particularly for smoothly varying potential landscapes, the transverse response consists of a sequence of disordering transitions with an intervening formation of stable channel structures.Comment: 7 pages, 6 postscript figures. Version to appear in Phys. Rev.

Simulation of How Jack Pine Budworm (Lepidoptera: Tortricidae) Affects Economic Returns From Jack Pine Timber Production in Michigan

The impact of jack pine budworm on economic returns from jack pine timber production in Lower Michigan and management actions that might be taken to reduce this impact were evaluated with a simulation model. Results indicate that current jack pine rotation ages arc excessive and should be reduced. Insecticide application is not a viable strategy for reducing jack pine budworm impact