Comparison of drop size distributions from two droplet sizing systems

A comparison between the Phase Doppler Particle Analyzer and the combined measurements from Particle Measuring Systems' Forward Scattering Spectrometer Probe and the Optical Array Probe was conducted in an icing wind tunnel using NASA Icing Research Tunnel spray nozzles to produce the supercooled water droplet cloud. Clouds having a range of volume median diameters from 10 to greater than 50 microns were used for the instrument comparisons. A volume median diameter was calculated from combining the droplet distributions of the Optical Array Probe and the Forward Scattering Spectrometer Probe. A comparison of the combined volume median diameters and the Phase Doppler Particle Analyzer volume median diameters showed agreement from 10 microns up to 30 microns. Typical drop size distributions from the Phase Doppler Particle Analyzer, the Forward Scattering Spectrometer Probe, and Optical Array Probe are presented for several median volume diameters. A comparison of the distributions illustrates regions of the distributions where there is good agreement and other regions where there are discrepancies between the Phase Doppler Particle Analyzer and the Particle Measuring Systems' droplet size instruments

Study on contraction and relaxation of experimentally denervated and immobilized muscles: Comparison with dystrophic muscles

The contraction-relaxation mechanism of experimentally denervated and immobilized muscles of the rabbit is examined. Results are compared with those of human dystrophic muscles, in order to elucidate the role and extent of the neurotrophic factor, and the role played by the intrinsic activity of muscle in connection with pathogenesis and pathophysiology of this disease

Data assimilation insights on selecting the most valuable atmospheric measurements

We discuss how objective guidance on selecting the most valuable atmospheric measurements on future Mars spacecraft missions can be provided through already developed Martian atmospheric data assimilation systems, and in particular through Observing System Simulation Experiments (OSSEs) which are widely used to design instruments for the Earth’s atmosphere

The measurement of aircraft performance and stability and control after flight through natural icing conditions

The effects of airframe icing on the performance and stability and control of a twin-engine commuter-class aircraft were measured by the NASA Lewis Research Center. This work consisted of clear air tests with artificial ice shapes attached to the horizontal tail, and natural icing flight tests in measured icing clouds. The clear air tests employed static longitudinal flight test methods to determine degradation in stability margins for four simulated ice shapes. The natural icing flight tests employed a data acquisition system, which was provided under contract to NASA by Kohlman Systems Research Incorporated. This system used a performance modeling method and modified maximum likelihood estimation (MMLE) technique to determine aircraft performance degradation and stability and control. Flight test results with artificial ice shapes showed that longitudinal, stick-fixed, static margins are reduced on the order of 5 percent with flaps up. Natural icing tests with the KSR system corroborated these results and showed degradation in the elevator control derivatives on the order of 8 to 16 percent depending on wing flap configuration. Performance analyses showed the individual contributions of major airframe components to the overall degration in lift and drag

A New Method for Calculating Arrival Distribution of Ultra-High Energy Cosmic Rays above 10^19 eV with Modifications by the Galactic Magnetic Field

We present a new method for calculating arrival distribution of UHECRs including modifications by the galactic magnetic field. We perform numerical simulations of UHE anti-protons, which are injected isotropically at the earth, in the Galaxy and record the directions of velocities at the earth and outside the Galaxy for all of the trajectories. We then select some of them so that the resultant mapping of the velocity directions outside the Galaxy of the selected trajectories corresponds to a given source location scenario, applying Liouville's theorem. We also consider energy loss processes of UHE protons in the intergalactic space. Applying this method to our source location scenario which is adopted in our recent study and can explain the AGASA observation above 4 \times 10^{19} eV, we calculate the arrival distribution of UHECRs including lower energy (E>10^19 eV) ones. We find that our source model can reproduce the large-scale isotropy and the small-scale anisotropy on UHECR arrival distribution above 10^19 eV observed by the AGASA. We also demonstrate the UHECR arrival distribution above 10^19 eV with the event number expected by future experiments in the next few years. The interesting feature of the resultant arrival distribution is the arrangement of the clustered events in the order of their energies, reflecting the directions of the galactic magnetic field. This is also pointed out by Alvarez-Muniz et al.(2002). This feature will allow us to obtain some kind of information about the composition of UHECRs and the magnetic field with increasing amount of data.Comment: 10 pages, 8 figures, to appear in the Astrophysical Journa

Stress evolution of anodic alumina films prior to the pore formation

Porous anodic oxide (PAO) films are grown by electrochemical oxidation of metals in a solution that dissolve the oxide. During the film formation, voltage increases linearly until the peak, then declines to steady-state value. PAO finds extensive usage as templates and substrates in many applications, such as solar cells and optical devices. However, the mechanism underlying the observed initiation and evolution of self-organized PAO structure is not understood. Recent studies on pore formation points out the role of plastic flow on pore initiation process [1–3]. In this study, we characterized stress profiles and its evolution during the film formation prior to the pore initiation. Phase-shifting curvature interferometry was used to monitor sample curvature change during film growth and subsequent dissolution. Oxide films were grown at constant current densities in 0.4 M H3PO4 until different thicknesses and subsequently current was turned off to dissolve grown oxide film. The stress profile of oxide film was revealed by in-situ monitoring the curvature change during dissolution of oxide film period after anodizing [4] . In addition, morphological evolution of oxide film during film growth was characterized using SEM. Oxide films growth until different thicknesses values up to onset of pore initiation instability. The measured stress change during film growth was in excellent agreement with prior measurements [5]. Measured stress profiles showed that for thin films \u3c20 nm, compressive stress was evenly dispersed through the thickness. However, for thicker films, the stress is concentrated within 20-nm thick layer near the solution interface. Transition in the stress profile coincides with oxide film thickness associated with initial roughening instability at the solution interface [6]. SEM images also showed that the first instability initiated at an oxide thickness of 20 nm with stable surface roughness pattern with a length scale of 20 nm. After the initial instability, the stress level near the solution interface became increasingly compressive as oxide film thickens. This behavior continued until the moment of self-ordered pore initiation when the both oxide thickness and the integrated oxide stress rapidly decreased to steady-state values. Morphological change during anodizing coincides with the stress transient, which could be attributed to the relaxation of elastic stress due to onset of plastic flow. Thus, plastic yielding in the oxide may induce a second instability mechanism involving pore initiation, leading to final self-ordered pore pattern. ACKNOWLEDGMENTS Support was provided by the National Science Foundation (CMMI-100748). REFERENCES [1] Garcia-Vergara, S.J., et al. Electrochim. Acta. 2006, 52, 681. [2] Houser, J.E., Hebert, K.R. Nature Mater. 2009, 8, 415. [3] Oh, J., Thompson, C.V. Electrochim. Acta. 2011, 56, 4044. [4] Çapraz, Ö.Ö., Shotriya, P., Hebert, K.R. J. Electrochem. Soc. 2014, 161, D256. [5] Çapraz, Ö.Ö., Hebert, K.R., Shotriya, P. J. Electrochem. Soc. 2013, 160, D501. [6] Hebert, K.R., et al. Nature Mater. 2012, 11, 162

Academic Procrastination and Self-Control in Thesis Writing Students of Faculty of Psychology, Universitas Surabaya

Procrastination has long been regarded as reflection of low self-control. The emergence of temporal motivation theory (TMT) as a theoretical framework to explain procrastination also supports the role of self-control in bringing forth procrastination. This study aimed to test the suitability of TMT in explaining correlational pattern of self-control and procrastination, both in general and in thesis completion. Subjects were 157 psychology students working on their thesis. The results show that self-control has a negative correlation with general procrastination (r = -0.663) and thesis (r=-0.504). The role of TMT’s elements as mediators has been proven when the negative correlations weakened significantly after controlling for TMT elements. Nevertheless, a greater attenuation was actually found when self-control was used as the mediator variable. Alleged causes and implications of the findings are discussed. Keywords: general procrastination, self-control, temporal motivation theory, undergraduate thesis procrastinatio

Excitons in Mott insulators

Motivated by recent Raman and resonant inelastic X-ray scattering experiments performed for Mott insulators, which suggest formation of excitons in these systems, we present a theory of exciton formation in the upper Hubbard band. The analysis based on the spin polaron approach is performed in the framework of an effective t-J model for the subspace of states with one doubly occupied site. Our results confirm the existence of excitons and bear qualitative resemblance to experimental data despite some simplifications in our approach. They prove that the basic underlying mechanismof exciton formation is the same as that which gives rise to binding of holes in weakly doped antiferromagnets.Comment: 4 pages, 1 figur