Stability of the replica symmetric solution in diluted perceptron learning

We study the role played by the dilution in the average behavior of a perceptron model with continuous coupling with the replica method. We analyze the stability of the replica symmetric solution as a function of the dilution field for the generalization and memorization problems. Thanks to a Gardner like stability analysis we show that at any fixed ratio $\alpha$ between the number of patterns M and the dimension N of the perceptron ($\alpha=M/N$), there exists a critical dilution field $h_c$ above which the replica symmetric ansatz becomes unstable.Comment: Stability of the solution in arXiv:0907.3241, 13 pages, (some typos corrected

PENGARUH RASIO PENGENCERAN BERBEDA TERHADAP KUALITAS SPERMA IKAN NILEM (Osteochillus hasselti) YANG DISIMPAN DALAM EKSTENDER SARI KURMA, SUSU DAN KUNING TELUR

The purpose of this research was to determine the quality of spermatozoa of Nilem Fish (Osteochillus hasselti) after storage in extender palm juice, milk and egg yolk with different dilution ratios. The treatment given was in the form of different dilution ratios between sperm and extender palm juice, milk and egg yolk, namely P1: dilution ratio 1:10, P2: dilution ratio 1:15 and P3: dilution ratio 1:20. The data obtained were analyzed by means of variance (ANOVA). Data that showed a significant effect were continued with further Duncan testing. The results showed that the treatment had a significant effect on motility and viability, but did not have a significant effect on fertility and hatchability

Surface evolution during crystalline silicon film growth by low-temperature hot-wire chemical vapor deposition on silicon substrates

We investigate the low-temperature growth of crystalline thin silicon films: epitaxial, twinned, and polycrystalline, by hot-wire chemical vapor deposition (HWCVD). Using Raman spectroscopy, spectroscopic ellipsometry, and atomic force microscopy, we find the relationship between surface roughness evolution and (i) the substrate temperature (230–350 °C) and (ii) the hydrogen dilution ratio (H2/SiH4=0–480). The absolute silicon film thickness for fully crystalline films is found to be the most important parameter in determining surface roughness, hydrogen being the second most important. Higher hydrogen dilution increases the surface roughness as expected. However, surface roughness increases with increasing substrate-temperature, in contrast to previous studies of crystalline Si growth. We suggest that the temperature-dependent roughness evolution is due to the role of hydrogen during the HWCVD process, which in this high hydrogen dilution regime allows for epitaxial growth on the rms roughest films through a kinetic growth regime of shadow-dominated etch and desorption and redeposition of growth species

Dilution jet mixing program, supplementary report

The velocity and temperature distributions predicted by a 3-D numerical model and experimental measurements are compared. Empirical correlations for the jet velocity trajectory developed are presented. The measured velocity distributions for all test cases of phase through phase 3 are presented in the form of contour and oblique plots. quantification of the effects of the following on the jet mixing characteristics with a confined crossflow are: (1) orifice geometry momentum flux ratio and density ratio; (2) nonuniform mainstream temperature and velocity profiles upstream of dilution orifices; (3) cold versus hot jet injection; (4) cross-stream flow are a convergence as encountered in practical dilution zone geometries; (5) 2-D slot versus circular orifices; (6) discrete noncirculcer orifices; (7) single-sided versus opposed jets; (8) single row of jets

Nanoparticle measurement methods in internal combustion engines

The primary objective of this study is to investigate the characteristics of nanoparticle formation in dilute exhaust streams from diesel engines. Nanoparticle formation may be due to condensation, homogenous nucleation, coagulation and adsorption from low temperature, sulfate and water in exhaust system. After being released from the tail pipe, new nanoparticles also might be formed due to nucleation growth from low dilution ratio and long residence time. On the other hand, nanoparticles might be formed from dilution tunnels themselves. The artifact formation in dilution tunnels is due to specific problems that may occur in a dilution device, such as dilution ratio, dilution air temperature, dilution air pressure, residence time and critical flow orifice. The experimental apparatus consists of a variable residence time, micro dilution system for exhaust dilution. Particle detection instruments consist of a scanning mobility particle sizer (SMPS), a condensation particle counter (CPC), and a NOx analyzer. Exhaust from modern diesel and gasoline engines was analyzed. Two dilution devices were designed to simulate the process of engine exhaust into the atmosphere. For high dilution ratio from 5 to 10,000:1 and variable long residence time of 50 to 2000 ms, a first dilutor, Dilutor I, was used. For low dilution ratio from 5 to 300:1 and short fixed residence time of 50 ms, a second dilutor, Dilutor II, was used. Temperature, dilution ratio, and residence time were controllable. A NOx analyzer was used to check dilution ratio. A series of experiments was done to calibrate the dilutors. The results showed that the dilution devices alter particle size if particles were not solid. Particle size measurements were taken upstream and downstream of a diesel particulate filter (DPF) with residence time changing from 50 ms to 700 ms, which increased nanoparticle concentrations by up to two orders of magnitude. Nanoparticles below about 20 nm in diameter were higher than in Microwave Regeneration Particulate Filter (MRPF) exhaust engine out during DPF regeneration. The research should help for any future measurements of nanoparticles. The nanoparticle formation and growth under different dilution conditions needs to be investigated further. A nanoparticle formation model could be built to understand homogenous nucleation. Due to the complex nature of the atmospheric dilution process, a dilution system could be developed in the laboratory to imitate the atmospheric processes. The University of Tennessee, Knoxville (UTK) and the Oak Ridge National Laboratory have joined in this research. The Graduate Automotive Technology Education (GATE) Center of UTK, sponsored by U.S. Department of Energy (DOE), was the main participant, and the research was be conducted at Advanced Propulsion Technology Center (APTC), a research and evaluation laboratory for new internal combustion engines and emissions controls technologies. The DOE Office of Heavy Vehicle Technologies sponsored the research

A visual validation of the combined effect of pH and dilution on the porosity of carbon xerogels

The hypothesis about the formation of the porous structure of carbon xerogels when the pH and the dilution ratio of the precursor solution are simultaneously modified has been validated by means of scanning electron microscope analysis. The morphology of the carbon xerogels showed that the size and number of the clusters produced during the sol–gel reaction is not only influenced by the pH but also by the dilution ratio. As with a decrease in the pH value, an increase in the dilution ratio caused the formation of a small number of large clusters, leading to materials with large pores. However, depending on the values selected the effect of the pH and dilution ratio was enhanced or diminished by the effect of the other. Hence, an appropriate adjustment of these two variables allowed microporous, micro-mesoporous and micro-macroporous materials to be obtained with pore volumes that could not be achieved by modifying the pH or the dilution ratio separately.Financial support from the Ministerio de Economía y Competitividad of Spain MINECO (under Projects MAT2011-23733 and IPT-2012-0689-420000, (BES-2012-052676)) is greatly acknowledged. NRR is also grateful to MINECO for her predoctoral research grant.Peer reviewe

Nitric oxide formation in gas turbine engines: A theoretical and experimental study

A modified Zeldovich kinetic scheme was used to predict nitric oxide formation in the burned gases. Nonuniformities in fuel-air ratio in the primary zone were accounted for by a distribution of fuel-air ratios. This was followed by one or more dilution zones in which a Monte Carlo calculation was employed to follow the mixing and dilution processes. Predictions of NOX emissions were compared with various available experimental data, and satisfactory agreement was achieved. In particular, the model is applied to the NASA swirl-can modular combustor. The operating characteristics of this combustor which can be inferred from the modeling predictions are described. Parametric studies are presented which examine the influence of the modeling parameters on the NOX emission level. A series of flow visualization experiments demonstrates the fuel droplet breakup and turbulent recirculation processes. A tracer experiment quantitatively follows the jets from the swirler as they move downstream and entrain surrounding gases. Techniques were developed for calculating both fuel-air ratio and degree of nonuniformity from measurements of CO2, CO, O2, and hydrocarbons. A burning experiment made use of these techniques to map out the flow field in terms of local equivalence ratio and mixture nonuniformity