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41.
Super-resolution: a comprehensive survey 总被引:3,自引:0,他引:3
Super-resolution, the process of obtaining one or more high-resolution images from one or more low-resolution observations, has been a very attractive research topic over the last two decades. It has found practical applications in many real-world problems in different fields, from satellite and aerial imaging to medical image processing, to facial image analysis, text image analysis, sign and number plates reading, and biometrics recognition, to name a few. This has resulted in many research papers, each developing a new super-resolution algorithm for a specific purpose. The current comprehensive survey provides an overview of most of these published works by grouping them in a broad taxonomy. For each of the groups in the taxonomy, the basic concepts of the algorithms are first explained and then the paths through which each of these groups have evolved are given in detail, by mentioning the contributions of different authors to the basic concepts of each group. Furthermore, common issues in super-resolution algorithms, such as imaging models and registration algorithms, optimization of the cost functions employed, dealing with color information, improvement factors, assessment of super-resolution algorithms, and the most commonly employed databases are discussed. 相似文献
42.
The packing stage starts at the end of mold filling. During this stage, additional material is forced into the mold to compensate for the shrinkage during subse-quent cooling. Underpacking results in molded parts with dimensional variation. Overpacking causes flash at the parting lines, stick during ejection, and excess residual stresses resulting in warpage. The packing stage is thus extremely important in the determination of the final quality of the product. Despite its importance, analysis of the packing stage has been relatively ignored, particularly the viscoelastic effect. In this work, the analysis of the isothermal packing stage is presented for a Maxwell fluid. A set of governing equations is derived for a two-dimensional mold and solved using the Galerkin finite element method. In addition to the distribution of velocity and pressure, the model predicts the stresses in the planar direction, which could be used for subsequent calculation of the residual stresses. 相似文献
43.
J. Mustafa M. S. Ahmad Jr. A. Rauf S. M. Osman 《Journal of the American Oil Chemists' Society》1990,67(12):937-939
Branched-chain thioethers have been prepared from methyl 4-oxo-trans-2-hexadecenoate and 9,12-dioxo-trans-10-octadecenoic acid. The reagents involved in these preparations were mercaptoacetic and mercaptopropionic acids. The yields
of these thioethers are almost quantitative. 相似文献
44.
A partex surface was modified by a UV‐curing system with epoxy acrylate (EB‐600). A set of formulations was prepared with oligomer and the trifunctional monomer trimethylol propane triacrylate in different combinations of percentages (1–5%) of sand to study the role of sand in various physical properties of UV‐cured thin films, as well as partex surfaces. Increased pendulum hardness (PH), gloss, adhesion, and abrasion values were obtained by the addition of sand into the partex surfaces. The best results were obtained with the formulation containing 3% sand. An enhanced PH and a decreased percentage of gel content of the UV‐cured film was observed with an increase of the sand concentration. A simulated weathering test was performed with partex surfaces cured by a formulation containing 3% sand in the base coat. The losses of the physical properties were found to be lower over the surface treated with the formulation containing sand. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2385–2392, 2002 相似文献
45.
A novel mechanism to form binary polymer blends is through phase separation by spinodal decomposition in the unstable region of the phase diagram. The present work investigates the effects of thermally‐induced phase separation by spinodal decomposition on the morphology development of liquid crystalline polymer/polycarbonate blends. Moreover, a thermodynamic binary phase diagram is obtained using a twin‐screw extruder at various processing melt temperatures. Differential scanning calorimetry and scanning electron microscopy were used to study the miscibility of the blends and the resulting morphology. A thermodynamic binary phase diagram exhibiting a lower critical solution temperature was obtained. The droplet size distribution of the blend was also obtained and discussed in light of the Cahn‐Hilliard theory. 相似文献
46.
Jamal Mustafa M. S. Ahmad A. Rauf S. M. Osman 《Journal of the American Oil Chemists' Society》1984,61(3):555-558
Methyl 4-oxo-trans-2-octadecenoate (II), when treated with excess hydrazoic acid in the presence of BF3-etherate, produced 66% methyl 5-aza-nonadec-trans-2-enoate (4,5-d)-tetrazole (III), 10% methyl 5-aza-nonadec-4-oxo-trans-2-enoate (IV) and 7% pentadecamide (V). Individual products were characterized by spectral and elemental methods. 相似文献
47.
Mohamed M. Abd-Alla Maher F. El-Zohry Kamal I. Aly Mohamed M. M. Abd-El-Wahab 《应用聚合物科学杂志》1993,47(2):323-329
A new interesting category of organometallic polyesters based on diarylidenecycloalkanones containing ferrocene derivatives in the polymer main chain has been prepared by interfacial polycondensation of 1,1′-dichlorocarbonyl ferrocene or 1,1′-dichlorocarbonyl-4,4′-diiodoferrocene with 2,5-bis(p-hydroxybenzylidene)cyclopentanone, 2,5-divanillylidenecyclopentanone, 2,6-bis(p-hydroxybenzylidene)cyclohexanone, 2,6-divanillylidenecyclohexanone, and 2,7-bis(p-hydroxybenzylidene) cycloheptanone. The resulting polyesters were characterized by elemental analyses, infrared spectroscopy, solubility, and viscometry measurements. The thermal behavior of the synthesized polymers was evaluated by thermal gravimetric analysis and correlated with their structures. The crystallinity of all polymers were examined by x-ray diffraction analysis. Moreover, the electrical conductivity of a selected example of polymer was investigated above the temperature range (300–500 K) and showed that it followed an Arrhenius-type equation with activation energy 2.09 eV. © 1993 John Wiley & Sons, Inc. 相似文献
48.
Some commonly used empirical equations of state for polymers are considered: the Spencer-Gilmore equation with two and three adjustable parameters, the Whitaker-Griskey equation, and the Rehage-Breuer equation. Also, a new equation is proposed: the Inverse Volume equation. These equations are evaluated with regard to fitting experimental P-V-T data and agreement with experimental data on isothermal compressibility and thermal expansion coefficient. The adjustable parameters for each equation are determined with the help of Rosenbrock's optimum-seeking technique. Analysis of the residuals on specific volume for a variety of materials suggests that the Spencer-Gilmore equation with three adjustable parameters, the Rehage-Breuer and the Inverse Volume equations yield the smallest and most random residuals and thus the least systematic error. The same three equations mentioned above yield results in good agreement with experimental isothermal compressibility data. However, among all the equations considered in this study, the Inverse Volume equation yields the best agreement with experimental thermal expansion coefficient data. Furthermore, it is the only equation to correctly predict the rise in thermal expansion coefficient with increasing temperature. 相似文献
49.
Ali A. Moazzami Stefanie L. Haese Afaf Kamal‐Eldin 《European Journal of Lipid Science and Technology》2007,109(10):1022-1027
Sesame seed (Sesamum indicum L.) is a rich source of furofuran lignans with a wide range of potential biological activities. The major lignans in sesame seeds are the oil‐soluble sesamin and sesamolin, as well as glucosides of sesaminol and sesamolinol that reside in the defatted sesame flour. Upon refining of sesame oil, acid‐catalyzed transformation of sesamin to episesamin and of sesamolin to epimeric sesaminols takes place, making the profile of refined sesame oils different from that of virgin oils. In this study, the total lignan content of 14 sesame seeds ranged between 405 and 1178 mg/100 g and the total lignan content in 14 different products, including tahini, ranged between 11 and 763 mg/100 g. The content of sesamin and sesamolin in ten commercial virgin and roasted sesame oils was in the range of 444–1601 mg/100 g oil. In five refined sesame oils, sesamin ranged between 118 and 401 mg/100 g seed, episesamin between 12 and 206 mg/100 g seed, and the total contents of sesaminol epimers between 5 and 35 mg/100 g seed, and no sesamolin was found. Thus, there is a great variation in the types and amounts of lignans in sesame seeds, seed products and oils. This knowledge is important for nutritionists working on resolving the connection between diet and health. Since the consumption of sesame seed products is increasing steadily in Europe and USA, it is important to include sesame seed lignans in databases and studies pertinent to the nutritional significance of antioxidants and phytoestrogens. It is also important to differentiate between virgin, roasted and refined sesame oils. 相似文献
50.
Nanocomposites of epoxy resin with montmorillonite clay were synthesized by swelling of different proportions of the clay in a diglycidyl ether of bisphenol‐A followed by in situ polymerization with aromatic diamine as a curing agent. The montmorillonite was modified with octadecylamine and made organophilic. The organoclay was found to be intercalated easily by incorporation of the epoxy precursor and the clay galleries were simultaneously expanded. However, Na‐montmorillonite clay could not be intercalated during the mixing or through the curing process. Curing temperature was found to provide a balance between the reaction rate of the epoxy precursor and the diffusion rate of the curing agent into the clay galleries. The cure kinetics were studied by differential scanning calorimetry. The exfoliation behavior of the organoclay system was investigated by X‐ray diffraction. Thermogravimetric analysis was used to determine the thermal stability, which was correlated with the ionic exchange between the organic species and the silicate layers. The morphology of the nanocomposites was evaluated by scanning electron microscopy. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2201–2210, 2004 相似文献