19,187 research outputs found
Adjustable indicating device for load position
An indicating device designed to provide an electrical signal relative to the position of a load is described. The device has a central housing with two wing structures on each side which support conventional switch means having cantilevered arms. Extending through the housing is a movable shaft that is spring biased to a forward extended position and adapted to respond against a load being positioned. The rear end of the movable shaft has an adjustable cam means which acts upon the cantilevered ams to cause a switching action upon shifting of the movable shaft by a load
Noncommutative Dynamics of Random Operators
We continue our program of unifying general relativity and quantum mechanics
in terms of a noncommutative algebra on a transformation groupoid
where is the total space of a principal fibre bundle
over spacetime, and a suitable group acting on . We show that
every defines a random operator, and we study the dynamics of
such operators. In the noncommutative regime, there is no usual time but, on
the strength of the Tomita-Takesaki theorem, there exists a one-parameter group
of automorphisms of the algebra which can be used to define a state
dependent dynamics; i.e., the pair , where is a state
on , is a ``dynamic object''. Only if certain additional conditions
are satisfied, the Connes-Nikodym-Radon theorem can be applied and the
dependence on disappears. In these cases, the usual unitary quantum
mechanical evolution is recovered. We also notice that the same pair defines the so-called free probability calculus, as developed by
Voiculescu and others, with the state playing the role of the
noncommutative probability measure. This shows that in the noncommutative
regime dynamics and probability are unified. This also explains probabilistic
properties of the usual quantum mechanics.Comment: 13 pages, LaTe
Detection and Characterization of Stress Symptoms in Forest Vegetation
Techniques used at the Pacific Southwest Forest and Range Experiment Station to detect advanced and previsual symptoms of vegetative stress are discussed. Stresses caused by bark beetles in coniferous stands of timber are emphasized because beetles induce stress more rapidly than most other destructive agents. Bark beetles are also the most damaging forest insects in the United States. In the work on stress symptoms, there are two primary objectives: (1) to learn the best combination of films, scales, and filters to detect and locate injured trees from aircraft and spacecraft, and (2) to learn if stressed trees can be detected before visual symptoms of decline occur. Equipment and techniques used in a study of the epidemic of the Black Hills bark beetle are described
Remote sensing in forestry: Promises and problems
There are no author-identified significant results in this report
Dynamical Effects of Nuclear Rings in Disk Galaxies
We investigate the dynamical response of stellar orbits in a rotating barred
galaxy potential to the perturbation by a nuclear gaseous ring. The change in
3D periodic orbit families is examined as the gas accumulates between the inner
Lindblad resonances. It is found that the phase space allowable to the x2
family of orbits is substantially increased and a vertical instability strip
appears with the growing mass of the ring. A significant distortion of the x1
orbits is observed in the vicinity of the ring, which leads to the intersection
between orbits with different values of the Jacobi integral. We also examine
the dependence of the orbital response to the eccentricity and alignment of the
ring with the bar. Misalignment between an oval ring and a bar can leave
observational footprints in the form of twisted near-infrared isophotes in the
vicinity of the ring. It is inferred that a massive nuclear ring acts to weaken
and dissolve the stellar bar exterior to the ring, whereas only weakly
affecting the orbits interior to the inner Lindblad resonances. Consequences
for gas evolution in the circumnuclear regions of barred galaxies are discussed
as well.Comment: 27 pages, 11 postscript figures included, latex using aastex 4.0,
uuencoded compressed tar file, to appear in Ap
Diagnosis and Treatment of Infectious Enteritis in Neonatal and Juvenile Ruminants.
Common causes of infectious enteritis in neonate and juvenile ruminants include viral, bacterial, and protozoal pathogens. The most common presenting sign in ruminants with infectious enteritis is diarrhea. Diagnosis of the cause of enteritis has important zoonotic and herd health implications. Severity of clinical signs with similar pathogens may differ between calves and small ruminants. Treatment of enteritis involves supportive care to correct fluid and electrolyte imbalances, provision of nutritional support for neonates, prevention and treatment of endotoxemia or sepsis, and pathogen-specific treatments when relevant and available
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Diagnosis and Treatment of Infectious Enteritis in Adult Ruminants.
Infectious enteritis in adult ruminants is often a result of 1 or more viral, bacterial, or parasitic pathogens. Diagnosis of etiologic agents causing enteritis is important when considering herd implications and zoonotic potential of some etiologies. Differential diagnoses for enteritis in adult ruminants is not simple based on clinical signs alone. Diagnostic samples include feces, blood, and antemortem and postmortem tissues. Treatment of infectious enteritis is aimed at correcting dehydration and electrolyte imbalances secondary to diarrhea. In cases of some bacterial and parasitic pathogens, additional targeted treatment and control are recommended. Management of enteritis may be instituted while awaiting laboratory test results
QCD Thermodynamics from the Lattice
We review the current methods and results of lattice simulations of quantum
chromodynamics at nonzero temperatures and densities. The review is intended to
introduce the subject to interested nonspecialists and beginners. It includes a
brief overview of lattice gauge theory, a discussion of the determination of
the crossover temperature, the QCD phase diagram at zero and nonzero densities,
the equation of state, some in-medium properties of hadrons including
charmonium, and some plasma transport coefficients.Comment: 74 pp. 31 figs. To appear in the European Physical Journal A and
Advances in Physics of Particles and Nuclei. Added references, corrected
typos, and updated the discussion of the thermal heavy quark/antiquark
potential. Added and updated references. Final versio
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