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131.
Synergizing spatial and temporal texture 总被引:1,自引:0,他引:1
Chin-Hwee Peh Loong-Fah Cheong 《IEEE transactions on image processing》2002,11(10):1179-1191
Temporal texture accounts for a large proportion of motion commonly experienced in the visual world. Current temporal texture techniques extract primarily motion-based features for recognition. We propose a representation where both the spatial and the temporal aspects of texture are coupled together. Such a representation has the advantages of improving efficiency as well as retaining both spatial and temporal semantics. Flow measurements form the basis of our representation. The magnitudes and directions of the normal flow are mapped as spatiotemporal textures. These textures are then aggregated over time and are subsequently analyzed by classical texture analysis tools. Such aggregation traces the history of a motion which can be useful in the understanding of motion types. By providing a spatiotemporal analysis, our approach gains several advantages over previous implementations. The strength of our approach was demonstrated in a series of experiments, including classification and comparisons with other algorithms. 相似文献
132.
Mensch Amy E. Hamins Anthony Tam Wai Cheong Lu Z. Q. John Markell Kathryn You Christina Kupferschmid Matthew 《Fire Technology》2021,57(6):2981-3004
Fire Technology - Cooking equipment is involved in nearly half of home fires in the United States, with cooktop fires the leading cause of deaths and injuries in cooking-related fires. In this... 相似文献
133.
Tests were carried out at passive mine water treatment sites in South Korea to determine how flow and pH affected other water quality parameters. Computational flow analysis and tracer tests revealed that the water took surprisingly direct flow routes in the oxidation ponds, while other areas remained stagnant. Furthermore, ferrous iron concentration, dissolved oxygen, pH, electrical conductivity, total dissolved solids, turbidity, and water depth were all directly affected by the flow patterns due to the relationship between retention time and iron precipitation. 相似文献
134.
Computational tools such as one-dimensional models or Computational Fluid Dynamics (CFD) have been used for the fire safety
design of road tunnels. However, most of these analyses are performed using a specified fire source where the heat release
rate (HRR) in the tunnel is fixed by the user and the influences of ventilation conditions and tunnel geometry are not considered.
For a more realistic estimate, models need to incorporate these factors in their input. This paper discusses the use of a
statistical approach previously developed by other researchers (Carvel and Beard, The handbook of tunnel fire safety. Thomas
Telford Publishing, pp 184–197, 2005) and the use of a CFD approach to estimate the HRR in a road tunnel fire. As an application
example, fire scenarios in which a light goods vehicle carrying wooden pallets are used to compare the estimation of the HRR
using these two methods. 相似文献
135.
P.G. Jayathilake Zhijun Tan B.C. Khoo N.E. Wijeysundera 《Chemical engineering science》2010,65(3):1237-1252
Although permeable and deformable capsules are found in many applications in biological and industrial systems, studies on computational modeling of these capsules are still rather lacking. In this work, the osmotic swelling of a deforming capsule immersed in a diluted binary solution of a non-electrolyte solute under Stokes flows is simulated using the immersed interface method (IIM). The approximate jump conditions for solute concentration are calculated with the use of the Kedem–Katchalsky relations. The capsule membrane is considered to be either semi-permeable or fully permeable, and the material of capsule membrane is assumed to be Neo-Hookean. The employed properties of fluid and membrane lie in the range of a typical biological system. The numerical validation tests indicate that the present calculation procedure has achieved good accuracy in modeling the swelling and deformation of permeable capsules. The capsule swelling (with mass transfer across the membrane) and deformation are tested for different solute concentration fields and membrane permeability properties. Our numerical investigations show that the initial solute concentration field and the membrane permeability properties have much influence on the swelling/deformation of a permeable capsule under Stokes flows. 相似文献
136.
Physiological and biochemical characteristics of the ethyl tiglate production pathway in the yeast Saprochaete suaveolens
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Eric Grondin Alain Shum Cheong Sing Yanis Caro Gustavo M. de Billerbeck Jean Marie François Thomas Petit 《Yeast (Chichester, England)》2015,32(1):57-66
A yeast identified as Saprochaete suaveolens was investigated for its capacity to produce a large panel of flavouring molecules. With a production of 32 compounds including 28 esters, S. suaveolens seems to be a good producer of fruity flavours and fragrances and especially of unsaturated esters, such as ethyl tiglate. Physiological and biochemical analyses were performed in this study in an attempt to comprehend the metabolic route to the formation of this compound. We show that the accumulation of ethyl tiglate by S. suaveolens is specifically induced by isoleucine. However, and contrary to S. cerevisiae, which harbours a classical Ehrlich pathway leading to the production of 2‐methylbutanol from isoleucine, our results provide phenotypic and enzymological evidence of ethyl tiglate biosynthesis in S. suaveolens through the catabolism of this amino acid by the β‐oxidation pathway, which generates tiglyl‐CoA as a probable intermediate. A kinetic analysis of this flavour molecule during growth of S. suaveolens on glucose and isoleucine showed a phase of production of ethyl tiglate that culminated concurrently with isoleucine exhaustion, followed by a disappearance of this compound, likely due to reassimilation by the yeast. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
137.
Chin Yung Lai Choke Fei Cheong Jit Singh Mandeep Huda Binti Abdullah Nowshad Amin Khin Wee Lai 《Journal of Materials Engineering and Performance》2014,23(10):3541-3550
The synthesis of silver nanoparticles for silver ink formation has attracted broad interest in the electronic part printing and semiconductor chip industry due to the extraordinary electrical and mechanical properties of these materials. The preparation of silver nanoparticles through a physical or chemical reduction process is the most common methodology applied to obtain nanoparticles with the required size, shape and surface morphology. The chemical solution or solvent carrier applied for silver ink formulation must be applied simultaneously with the direct writing technique to produce the desired adherence, viscosity, and reliable performance. This review paper discusses the details concerning the past and recent advancement of the synthesis and characterization of silver nanoparticles and silver ink formation. A review on the advantages of various sintering techniques, which aim to achieve the electrical and mechanical properties of the required printed structure, is also included. A brief summary concerning the recent challenges and improvement approaches is presented at the end of this review. 相似文献
138.
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140.
The study investigates the effect of inherent structural properties of liquid substrates on physical vapor-deposited metallic condensates. Due to the limitations in characterizing the atomic structure of different kinds of liquids, quantitative analysis of all the influencing parameters of the liquid substrate is difficult. Real time considered computing simulation is called for to realize the effects of such properties, which gives direct analyzable results. As representatives of physical and chemical properties of substrates, the molecular frequency and adsorption probability (~binding energy) are utilized as the key simulation parameters. Nucleation kinetics represented by conventional equations and an adapted time algorithm are employed to guarantee a correct, comparable and efficient simulation technique. The results show the substrates’ influence on the ‘morphology’ and ‘formation time’ of the film. In particular, the non-uniform morphology and low coverage observed under ‘liquid-substrate conditions’ are in agreement with experimental observations. The method can also be applied for predicting the condensate morphology for various vapor/substrate systems with known conditions. 相似文献