On direction of spontaneous magnetization in a "cubic" ferromagnet

The magnetic properties of anisotropic films have been studied using 3D-neutron polarization analysis. The experimental facts refer to essential distinction of the sample states, magnetized in opposite directions. For an explanation of asymmetrical effects the model is offered, in which the fundamental theoretical principles of structural phase transitions are used.Comment: 4 pages LaTeX (phbauth) and 4 figures (epsfig

Infrared radiation measurements of combustion gases third quarterly progress report, 1 jan. - 31 mar. 1965

Infrared absorption spectrum measurements of carbon monoxide - exhaust gase

Temperature Dependence Of Brillouin Light Scattering Spectra Of Acoustic Phonons In Silicon

Electrons, optical phonons, and acoustic phonons are often driven out of local equilibrium in electronic devices or during laser-material interaction processes. The need for a better understanding of such non-equilibrium transport processes has motivated the development of Raman spectroscopy as a local temperature sensor of optical phonons and intermediate frequency acoustic phonons, whereas Brillouin light scattering (BLS) has recently been explored as a temperature sensor of low-frequency acoustic phonons. Here, we report the measured BLS spectra of silicon at different temperatures. The origins of the observed temperature dependence of the BLS peak position, linewidth, and intensity are examined in order to evaluate their potential use as temperature sensors for acoustic phonons. (C) 2015 AIP Publishing LLC.National Science Foundation (NSF) Thermal Transport Processes Program CBET-1336968PhysicsCenter for Complex Quantum SystemsMaterials Science and EngineeringTexas Materials InstituteMechanical Engineerin

The study of base heating by radiation from exhaust gases final report, oct. 1, 1963 - sep. 30, 1964

Base heating by radiation from exhaust gase

TinyQMIX: Distributed Access Control for mMTC via Multi-agent Reinforcement Learning

Distributed access control is a crucial component for massive machine type communication (mMTC). In this communication scenario, centralized resource allocation is not scalable because resource configurations have to be sent frequently from the base station to a massive number of devices. We investigate distributed reinforcement learning for resource selection without relying on centralized control. Another important feature of mMTC is the sporadic and dynamic change of traffic. Existing studies on distributed access control assume that traffic load is static or they are able to gradually adapt to the dynamic traffic. We minimize the adaptation period by training TinyQMIX, which is a lightweight multi-agent deep reinforcement learning model, to learn a distributed wireless resource selection policy under various traffic patterns before deployment. Therefore, the trained agents are able to quickly adapt to dynamic traffic and provide low access delay. Numerical results are presented to support our claims.Comment: 6 pages, 4 figures, presented at VTC Fall 202

Inferring periodic orbits from spectra of simple shaped micro-lasers

Dielectric micro-cavities are widely used as laser resonators and characterizations of their spectra are of interest for various applications. We experimentally investigate micro-lasers of simple shapes (Fabry-Perot, square, pentagon, and disk). Their lasing spectra consist mainly of almost equidistant peaks and the distance between peaks reveals the length of a quantized periodic orbit. To measure this length with a good precision, it is necessary to take into account different sources of refractive index dispersion. Our experimental and numerical results agree with the superscar model describing the formation of long-lived states in polygonal cavities. The limitations of the two-dimensional approximation are briefly discussed in connection with micro-disks.Comment: 13 pages, 19 figures, accepted for publication in Physical Review

Gradient Clogging in Depth Filtration

We investigate clogging in depth filtration, in which a dirty fluid is ``cleaned'' by the trapping of dirt particles within the pore space during flow through a porous medium. This leads to a gradient percolation process which exhibits a power law distribution for the density of trapped particles at downstream distance x from the input. To achieve a non-pathological clogging (percolation) threshold, the system length L should scale no faster than a power of ln w, where w is the width. Non-trivial behavior for the permeability arises only in this extreme anisotropic geometry.Comment: 4 pages, 3 figures, RevTe

Effects of Bioactive Glass Scaffold and BMP-2 in Segmental Defects

poster abstractReconstruction of segmental defects in the load-bearing area has long been a challenge in orthopaedics. We have demonstrated the feasibility of a biodegradable load-bearing scaffold fabricated from poly(propylene fumarate)/tricalcium phosphate (PPF/TCP) loaded with bone morphogenetic protein-2 (BMP-2) to successfully induce healing in those defects. However, there is limited osteoconduction observed with the PPF/TCP scaffold itself. Furthermore, a recent review on BMP-2 revealed greater risks in radiculities, ectopic bone formation, osteolysis and poor global outcome in association with the use of BMP-2 for spinal fusion. The aims of this study were to evaluate the potential use of a more osteoconductive material 13-93 bioactive glass and the potential side effects of locally delivered BMP-2 on adjacent bones. 13-93 glass scaffolds were fabricated by indirect selective laser sintering and implanted into critical size defects created in rat right femurs with and without 10 micrograms of BMP-2. The X-ray and micro-CT results showed that bridging callus was found as soon as 3 weeks and progressed gradually in the BMP group while minimal bone formation was observed in the control group. As expected, stiffness, peak load and energy to break of the BMP group were all higher than the control group. Higher healing rates in the 13-93 group was found compared to the healing rate in PPF/TCP group evaluated in the past indicating a more osteoconductive nature of the 13-93 scaffolds. The scaffolds of both control and BMP groups were partially degraded after 15 weeks as seen in the histological images. For the effects of local BMP-2 delivery to adjacent bones, no statistical difference in the bone area, mineral content and mineral density was found between control and BMP groups. In conclusion, a 13-93 bioactive glass scaffold with local BMP-2 delivery has been demonstrated for its potential application in treating large bone defects

Summary of combustion instability research at Princeton University, 1969

Control and causes of combustion instability in rocket engine