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61.
In the field of images and imaging, super-resolution (SR) reconstruction of images is a technique that converts one or more low-resolution (LR) images into a highresolution (HR) image. The classical two types of SR methods are mainly based on applying a single image or multiple images captured by a single camera. Microarray camera has the characteristics of small size, multi views, and the possibility of applying to portable devices. It has become a research hotspot in image processing. In this paper, we propose a SR reconstruction of images based on a microarray camera for sharpening and registration processing of array images. The array images are interpolated to obtain a HR image initially followed by a convolution neural network (CNN) procedure for enhancement. The convolution layers of our convolution neural network are 3×3 or 1×1 layers, of which the 1×1 layers are used to improve the network performance particularly. A bottleneck structure is applied to reduce the parameter numbers of the nonlinear mapping and to improve the nonlinear capability of the whole network. Finally, we use a 3×3 deconvolution layer to significantly reduce the number of parameters compared to the deconvolution layer of FSRCNN-s. The experiments show that the proposed method can not only ameliorate effectively the texture quality of the target image based on the array images information, but also further enhance the quality of the initial high resolution image by the improved CNN. 相似文献
62.
Shabir Ahmad Mir Sowriappan John Don Bosco Manzoor Ahmad Shah Mohammad Maqbool Mir Kappat Valiyapeediyekkal Sunooj 《International Journal of Food Properties》2016,19(9):2102-2112
The popping process was optimized for brown rice based on an expansion ratio. A central composite design with interactive effect of three independent variables, including salt content (1–2.5 g/100 g raw material), moisture content (13–17 g/100 g raw material), and popping temperature (210–240°C) was used to study their effects on the expansion ratio of rice using response surface methodology. The experimental values of expansion ratio were ranged from 5.24 to 6.85. On fitting the experimental values of expansion ratio to a second order polynomial equation, a mathematical model with the predictability was developed with the statistical adequacy and validity (p ? 0.05). From the model, the optimal condition including salt content (1.75 g/100 g raw material), moisture content (15 g/100 g raw material), and popping temperature (225°C) were predicted for a maximum expansion ratio of 6.79, which was then proved to be 6.85 through experiment. Raw and popped brown rice were investigated for physical properties including hardness, L*, a*, and b* value, length/breadth ratio, bulk density, and minerals, which showed the significant differences. The optimized popped rice sample was evaluated for structural, spectroscopic, and thermal properties, which showed the significant difference from raw rice. 相似文献
63.
Understanding the chemistry of milk and its components is critical to the production of consistent, high-quality dairy products as well as the development of new dairy ingredients. Over the past 100 yr we have gone from believing that milk has only 3 protein fractions to identifying all the major and minor types of milk proteins as well as discovering that they have genetic variants. The structure and physical properties of most of the milk proteins have been extensively studied. The structure of the casein micelle has been the subject of many studies, and the initial views on submicelles have given way to the current model of the micelle as being assembled as a result of the concerted action of several types of interactions (including hydrophobic and the formation of calcium phosphate nanoclusters). The benefits of this improved knowledge of the type and nature of casein interactions include better control of the cheesemaking process, more functional milk powders, development of new products such as cream liqueurs, and expanded food applications. Increasing knowledge of proteins and minerals was paralleled by developments in the analysis of milk fat and its synthesis together with greater knowledge of its packaging in the milk fat globule membrane. Advances in analytical techniques have been essential to the isolation and characterization of milk components. Milk testing has progressed from gross compositional analyses of the fat and total solids content to the rapid analysis of milk for a wide range of components for various purposes, such as diagnostic issues related to animal health. Up to the 1950s, research on dairy chemistry was mostly focused on topics such as protein fractionation, heat stability, acid–base buffering, freezing point, and the nature of the calcium phosphate present in milk. Between the 1950s and 1970s, there was a major focus on identifying all the main protein types, their sequences, variants, association behavior, and other physical properties. During the 1970s and 1980s, one of the major emphases in dairy research was on protein functionality and fractionation processes. The negative cloud over dairy fat has lifted recently due to multiple reviews and meta-analyses showing no association with chronic issues such as cardiovascular disease, but changing consumer misconceptions will take time. More recently, there has been a great deal of interest in the biological and nutritional components in milk and how these materials were uniquely designed by the cow to achieve this type of purpose. 相似文献
64.
Biodegradable polymer blends of high-molecular-weight poly(3-hydroxybutyrate) (PHB) and poly(lactic acid) (PLA) are not miscible in general. Yet, by decreasing the molecular weight of PHB, the low-molecular-weight PHB could have improved miscibility with the PLA. In this study, a melt-induced degradation process of PLA/PHB blends was therefore implemented, termed the in-situ self-compatibilization approach, to produce low-molecular-weight PHB during melt blending process. The solution blends of PLA and oligomer PHB (PLA/OPHB) were also prepared as a basis to understand the role of low-molecular-weight PHB to improve its miscibility with PLA in PLA/PHB blends. Only one single glass transition temperature (Tg) was found for the resulting PLA/PHB blends at compositions of 95/05 to 80/20, proving that the miscibility was greatly improved by decreasing molecular weight of PHB. Because the degraded PHB had a relatively lower Tg, it thus provided plasticization effect to the PLA and resulted in the decreased crystallization temperature. Moreover, with increasing PHB content to 20% in the blend, the elongation at break increased significantly from 7.2% to 227%, more than 30-fold. The extensive shear yielding and necking behavior were observed during tensile testing for the blend of 80/20. The localized plasticization within PLA/PHB matrix with the reduction of local yield stress and the well-dispersed PHB crystallites were the major contributing factors to trigger shear yielding phenomenon. Moreover, initial modulus decreased only 20%, from 1.68 to 1.35 GPa. A common problem of severely reduced stiffness from the added plasticizer encountered in the plasticized PLA blends was therefore not perceived here. 相似文献
65.
In this research, poly(3,4-ethylenedioxythiophene) (PEDOT) nanoparticles less than 100 nm were synthesized first and applied as the solid stabilizer for producing PEDOT-polystyrene (PEDOT-PSt) composite latex by Pickering emulsion polymerization. The results showed that most PEDOT nanoparticles adhered to the PSt core particles having the size from 100 to 250 nm. By casting the latex, the obtained PEDOT-PSt film had a surface resistance of 4–5 kΩ/□, almost the same as the pure PEDOT film, though its PEDOT content was only 6.2 wt%. Those PEDOT nanoparticles in the outer layer could contact with one another, forming a continuous network as the conductive passageway. Furthermore, soft latex particles of poly(styrene-co-butyl acrylate), P(St-BA), were synthesized and mixed with the conducting rigid PEDOT-PSt latex for improving the toughness and transparency of the casting film. A critical point at about 2 wt% of PEDOT content in the PEDOT-PSt/P(St-BA) film was observed in the surface resistance measurement. 相似文献
66.
Simulation of DME synthesis from coal syngas by kinetics model 总被引:1,自引:0,他引:1
Hyun Min Shim Seung Jong Lee Young Don Yoo Yong Seung Yun Hyung Taek Kim 《Korean Journal of Chemical Engineering》2009,26(3):641-648
DME (Dimethyl Ether) has emerged as a clean alternative fuel for diesel. There are largely two methods for DME synthesis.
A direct method of DME synthesis has been recently developed that has a more compact process than the indirect method. However,
the direct method of DME synthesis has not yet been optimized at the face of its performance: yield and production rate of
DME. In this study it is developed a simulation model through a kinetics model of the ASPEN plus simulator, performed to detect
operating characteristics of DME direct synthesis. An overall DME synthesis process is referenced by experimental data of
3 ton/day (TPD) coal gasification pilot plant located at IAE in Korea. Supplying condition of DME synthesis model is equivalently
set to 80 N/m3 of syngas which is derived from a coal gasification plant. In the simulation it is assumed that the overall DME synthesis
process proceeds with steadystate, vapor-solid reaction with DME catalyst. The physical properties of reactants are governed
by Soave-Redlich-Kwong (SRK) EOS in this model. A reaction model of DME synthesis is considered that is applied with the LHHW
(Langmuir-Hinshelwood Hougen Watson) equation as an adsorption-desorption model on the surface of the DME catalyst. After
adjusting the kinetics of the DME synthesis reaction among reactants with experimental data, the kinetics of the governing
reactions inner DME reactor are modified and coupled with the entire DME synthesis reaction. For validating simulation results
of the DME synthesis model, the obtained simulation results are compared with experimental results: conversion ratio, DME
yield and DME production rate. Then, a sensitivity analysis is performed by effects of operating variables such as pressure,
temperature of the reactor, void fraction of catalyst and H2/CO ratio of supplied syngas with modified model. According to simulation results, optimum operating conditions of DME reactor
are obtained in the range of 265–275 °C and 60 kg/cm2. And DME production rate has a maximum value in the range of 1–1.5 of H2/CO ratio in the syngas composition. 相似文献
67.
Yoojin Jung Paul T. Imhoff Don C. Augenstein Ramin Yazdani 《Canadian Metallurgical Quarterly》2009,135(3):138-146
Gas collection systems of various designs have been used to control landfill gas emissions, which can be problematic, particularly before installation of final landfill covers. In this work, an innovative gas collection system that includes a permeable layer near the top surface of landfills was evaluated for enhancing capture of landfill gas and reducing fugitive methane emissions. A computational model that accounts for advective and diffusive fluxes of multiple gas components was used to evaluate the efficiency of this new design for intermediate landfill covers. The utility of the high-permeability gas-conductive layer was illustrated for several conditions of interest including varying refuse permeability, varying degrees of permeability anisotropy, and temporal atmospheric pressure changes. Simulations showed that the permeable layer decreased methane emissions by 43% when the horizontal to vertical permeability ratio for refuse was kh/kv = 3 and the domain average kh = 3×10?12?m2, while reductions in methane emissions decreased to 17% for the same anisotropy but with kh = 10?11?m2. With this design, barometric pressure changes did not significantly affect oxygen intrusion or methane emission rates. 相似文献
68.
Crystalline titanium dioxide (TiO2) coatings have been widely used in photo-electrochemical solar cell applications. In this study, TiO2 and carbon-doped TiO2 coatings were deposited onto unheated titanium and silicon wafer substrates using a DC closed-field magnetron sputtering system. The resultant coatings had an amorphous structure and a post-deposition heat treatment is required to convert this amorphous structure into the photoactive crystalline phase(s) of TiO2. This study investigates the use of a microwave plasma heat treatment as a means of achieving this crystalline conversion. The treatment involved placing the sputtered coatings into a 2.45 GHz microwave-induced nitrogen plasma where they were heated to approximately 550 °C. It was observed that for treatment times as short as 1 min, the 0.25-μm thick coatings were converted into the anatase crystalline phase of TiO2. The coatings were further transformed into the rutile crystalline phase after treatments at higher temperatures. The doping of TiO2 with carbon was found to result in a reduction in this phase transformation temperature, with higher level of doping (up to 5.8% in this study) leading to lower anatase-to-rutile transition temperature. The photoactivity performance of both doped and un-doped coatings heat-treated using both furnace and microwave plasma was compared. The carbon-doped TiO2 exhibited a 29% increase in photocurrent density compared to that observed for the un-doped coating. Comparing carbon-doped coatings heat-treated using the furnace and microwave plasma, it was observed that the latter yielded a 19% increase in photocurrent density. This enhanced performance may be correlated to the differences in the coatings' surface morphology and band gap energy, both of which influence the coatings' photoabsorption efficiency. 相似文献
69.
Zang Hee Cho Young Don Son Eun Jung Choi Hang Keun Kim Jeong Hee Kim Sang Yoon Lee Seiji Ogawa Young Bo Kim 《Magma (New York, N.Y.)》2013,26(1):71-79
Advances in the new-generation of ultra-high-resolution, brain-dedicated positron emission tomography-magnetic resonance imaging (PET/MRI) systems have begun to provide many interesting insights into the molecular dynamics of the brain. First, the finely delineated structural information from ultra-high-field MRI can help us to identify accurate landmark structures, thereby making it easier to locate PET activation sites that are anatomically well-correlated with metabolic or ligand-specific organs in the neural structures in the brain. This synergistic potential of PET/MRI imaging is discussed in terms of neuroscience and neurological research from both translational and basic research perspectives. Experimental results from the hippocampus, thalamus, and brainstem obtained with 18F-fluorodeoxyglucose and 11C-3-amino-4-(2-dimethylaminomethylphenylsulfanyl)benzonitrile are used to demonstrate the potential of this new brain PET/MRI system. 相似文献
70.