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101.
This paper describes a new approach to behavioral mode choice modeling using neurofuzzy models. The new approach combines the learning ability of artificial neural networks and the transparent nature of fuzzy logic. The approach is found to be highly adaptive and efficient in investigating nonlinear relationships among different variables. In addition, the approach only selects the variables that significantly influence the mode choice and displays the stored knowledge in terms of fuzzy linguistic rules. This allows the modal decision-making process to be examined and understood in great detail. The neurofuzzy model is tested on the U.S. freight transport market using information on individual shipper and individual shipments. Shipments are disaggregated at the five-digit Standard Transportation Commodity Code level. Results obtained from this exercise are compared with similar results obtained from the conventional logit mode choice model and the standard back-propagation artificial neural network. The advantages of using the neurofuzzy approach are described. 相似文献
102.
The exterior optical surfaces of satellites are directly exposed to the harsh space environment. Thermal control paints are resistant to the conditions encountered at low earth orbit (LEO): vacuum, atomic oxygen, thermal cycling, and ultraviolet radiation. In this paper two white paints were prepared by ultrasonic dispersing method for application to space structures. The white paints include zinc-oxide-pigmented silicone elastomer SilGel 612 (U1) and a zinc-oxide-pigmented silicone elastomer RT604 (U2). These coatings are electrically non-conductive. We present the behavior of thermal control paints under atomic oxygen (AO). The effects of AO exposure were studied by the mass loss of paint specimens and complementary techniques including scanning electron microscopy (SEM) and atomic force microscopy (AFM). Also the optical degradation in the reflectance spectra, solar absorptance and thermal emittance for U1 and U2 samples before and after AO exposure were investigated. The paints have promising AO resistance properties that could be suitable for space applications. 相似文献
103.
Somaieh Rahaie Zahra Emam‐Djomeh Sayed Hadi Razavi Mansoureh Mazaheri 《International Journal of Food Science & Technology》2012,47(8):1647-1653
In this study, the surface binding ability of Saccharomayces cerevisiae and Lactobacillus rhamnosus GG (LBGG) to aflatoxin in pistachio nuts was compared. Results showed that Saccharomayces cerevisiae and Lactobacillus rhamnosus strains had aflatoxin binding ability of 40% and 35% with initial concentration of 10 ppb and 70% and 60% with initial concentration of 20 ppb aflatoxin, respectively. Acid treatment increased this ability for yeast and bacterium to 60% and 85% in first concentration and 73% and 90% for second concentration of aflatoxin, respectively. Also, heat treatment could raise surface binding of yeast to 55% and 75% for two concentrations. In addition, heat condition for Lactobacillus improved binding to 85% and 90% for two concentrations of aflatoxin. Experiments showed that microorganism’s immobilisation on contaminated pistachio had no effect on qualitative characteristics of pistachio such as colour, texture and peroxide value. 相似文献
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Seyed M. A. Razavi Seyed Ali Mortazavi Lara Matia-Merino Seyed H. Hosseini-Parvar Ali Motamedzadegan & Elham Khanipour 《International Journal of Food Science & Technology》2009,44(9):1755-1762
Basil seed ( Ocimum basilicum L.) is cultivated in large quantities in different regions of Iran. This seed has reasonable amounts of gum with good functional properties which is comparable with commercial food hydrocolloids. A central composite rotatable design was applied to evaluate the effects of temperature, pH and water/seed ratio on the yield, apparent viscosity and protein content of water-extracted Basil seed gum. All of the variables significantly ( P < 0.05) affected the extraction yield, whereas the effect of water/seed ratio on apparent viscosity and the effects of pH and water/seed ratio on protein content were not significant ( P > 0.05). Numerical optimisation determined the optimum extraction conditions based on the highest yield and viscosity and the lowest protein content as being temperature 68.71 °C, pH 8.09 and water/seed ratio 65.98:1. Power law model well described non-Newtonian pseudoplastic behaviour of BSG. Flow behaviour index ( n ) and consistency index ( K ) of 1% crude and pure BSG samples were 0.306, 0.283 and 17.46, 20.22 Pa s n , respectively. 相似文献
106.
Synthesis, contact printing, and device characterization of Ni-catalyzed, crystalline InAs nanowires
Alexandra C. Ford Johnny C. Ho Zhiyong Fan Onur Ergen Virginia Altoe Shaul Aloni Haleh Razavi Ali Javey 《Nano Research》2008,1(1):32-39
InAs nanowires have been actively explored as the channel material for high performance transistors owing to their high electron
mobility and ease of ohmic metal contact formation. The catalytic growth of nonepitaxial InAs nanowires, however, has often
relied on the use of Au colloids which is non-CMOS compatible. Here, we demonstrate the successful synthesis of crystalline
InAs nanowires with high yield and tunable diameters by using Ni nanoparticles as the catalyst material on amorphous SiO2
substrates. The nanowires show superb electrical properties with field-effect electron mobility ~2700 cm2/Vs and ION/IOFF
>103. The uniformity and purity of the grown InAs nanowires are further demonstrated by large-scale assembly of parallel arrays
of nanowires on substrates via the contact printing process that enables high performance, “printable” transistors, capable
of delivering 5 10 mA ON currents (~400 nanowires). 相似文献
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Oscillatory measurements were used to investigate the effect of temperature and concentration on the viscoelastic and gelling properties of basil seed gum (BSG). Linear viscoelastic region was determined by strain sweep and it was found in 0.5% strain. Storage modulus (G′) was greater than loss modulus (G″) in all concentrations and they increased by improving BSG concentration. Yield stress value was determined by stress sweep and it increased from 1.40 to 7.47 Pa when BSG concentration increased from 1% to 3%. Frequency sweep showed BSG solution was a typical weak gel, and complex viscosity (η*) had linear correlation with frequency. The effect of temperature on gel forming was investigated during heating (20–90 °C) and cooling (90–20 °C) phases. BSG was characterised as a thermo‐reversible gel and did not have thermal hysteresis. Gelling temperature was raised as BSG concentration was increased. Exhibiting special rheological properties of BSG makes it as a proper synergistic gel, which can be applied in real food systems such as dairy desserts. 相似文献