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101.
The Shape-from-Template (SfT) problem is to recover the 3D shape of a deformable object from a single image, given a 3D template and a deformation constraint. We propose Particle-SfT, a new SfT algorithm which handles isometric and non-isometric deformations. We build Particle-SfT upon a particle system guided by deformation and reprojection constraint projections. Reconstruction is achieved by evolving particles to a globally attractive equilibrium, while taking observable external forces such as gravity into account, if any. Particle-SfT may be used to refine an existing initial shape. However, in practice we simply use the template as initial guess. This is because, as opposed to the existing refining methods, Particle-SfT has an extremely wide convergence basin. Particle-SfT is also faster than the existing refining methods. This is because it moves pieces of the shape’s mesh independently to achieve larger step size by optimal constraint projection. We proved its convergence to a fixed-point. We experimented it with synthetic and real data. It has the same accuracy as the best performing isometric method and consistently outperforms all existing elastic methods in almost all cases, while being much faster. 相似文献
102.
The authors derived a set of analytical models for serial production lines with multiple operation stations and multiple inspection/repair stations. Multiple defect types may be acquired by the production units from the raw stock as well as during processing at operation stations. The analytical models are steady-state equations for outgoing quality level, throughput rate and scrap rates. The analytical models are based on (1) traffic rate equations of the flow through a production line when represented as a directed flow network and (2) probabilistic models of changes in defect attributes of the production units as they flow. The formulas may be used for evaluating inspection configuration designs including the formulation of optimal cost models. 相似文献
103.
104.
Gaining strategic advantages require companies to adopt customer satisfaction as a core strategy that constitutes the fundamentals of total quality management and just in time philosophies. Total quality management and just in time have been used for some time in manufacturing; however, this research extends the idea into purchasing by adapting qualitative and quantitative tools to create a methodology that can be used to design purchasing processes. This paper solely presents the supplier selection and performance management system dimensions of the methodology followed by a case study to illustrate application in the purchasing department of a Turkish steel company. 相似文献
105.
The effects of polarization on properties of activated carbon cloth (ACC) have been investigated systematically. The polarization-treated ACC samples were prepared by polarizing them in Na2SO4 or KH2PO4/KOH buffer solutions at potentials from −1.5 to 5.0 V. The properties, such as surface area, pore size distribution (PSD), total pore volume, amount and nature of the surface functional groups and surface acidity, of pristine and polarization-treated ACC samples were determined. The samples were also characterized electrochemically by determining the properties such as specific capacitance and potential at point of zero charge (EPZC). Anodic polarization in different electrolytes was found to cause oxidation on ACC. Although the surface textural properties did not change considerably, the changes took place in chemical and electrochemical properties upon anodic polarization were found to be important. The increase in surface acidity shifted the pHPZC from 7.40 to 3.21 and EPZC from 164 to 355 mV. The optimum potential range, considered to be safe for polarization of ACC, was determined as −1.5 to +0.8 V. 相似文献
106.
A comparative study on the efficiencies of polyethylene compatibilizers by using theoretical methods
Functionalization of polyethylene chains by grafting of polar groups onto backbones is the most versatile way for preparing
polyethylene based compatibilizers (PECs). In this work, a series of theoretical studies were performed to analyze the structure,
adhesion and mixing behaviors of PECs. The effect of grafting different polar groups such as acrylic acid (AA), glycidyl methacrylate
(GMA), maleic anhydride (MAH) and itaconic acid (IA) on the structure and cohesive properties of polyethylene chains were
studied by Molecular Dynamics simulations. The mixing behavior of grafted polyethylenes with some commodity polymers such
as polyetylene teraphthalate (PET), polyamide 6 (Nylon6), polyvinyl acetate (PVA) and polylactide (PLA) as well as with starch
(ST) and starch acetate (STac) were investigated quantitatively by determining accurate interaction parameters using the modified
Flory-Huggins Theory. We showed that the polar groups are the most reactive sites and they bind the chemically incompatible
polymers by enabling the stronger interactions at the interfacial region. 相似文献
107.
The purpose of this study is to compare laboratory and field performances for dense graded asphalt mixtures. Control road pavement section was constructed in Black Sea Coast Highway. Marshall identical control samples produced in laboratory and core samples taken from wearing courses before the traffic opened were used. Three different moisture conditioning methods were applied to control laboratory and core samples. Mechanical properties of samples were evaluated with indirect tension, indirect tension strength and repeated creep tests. Indirect tensile strength test results for laboratory mixtures were found 1.22 and 1.30 times more in accordance with field samples at 10 °C and 20 °C respectively. Marshall samples gave higher resilient modulus for all control and conditioned mixtures. Repeated creep test results also proved the difference between laboratory and field sample performance. Laboratory samples protected their structural integrity along with the test duration and did not showed tertiary creep. It is concluded from this study that laboratory samples state expressly higher performance according to the core field samples. 相似文献
108.
研究了锻造态和热处理态不同成分铝基轴承合金在油润滑条件下的摩擦行为,以及材料的硬度、热处理制度和锻造对材料耐磨性的影响。所用材料是 Al-8.5Si-3.5Cu 和 Al-15Pb-3.7Cu-1.5Si-1.1Fe。在锻造过程中,应变范围为10%~20%。并对材料进行T6热处理。在销-盘式磨损试验机上对材料的摩擦性能进行测试。结果表明,锻造过程使材料的硬度得到增加;铸造应变在10%~20%的范围内对材料的摩擦磨损影响不明显。 相似文献
109.
A new supervised classification method is developed for quantitative analysis of remotely-sensed multi-spectral data. It is based on the comparisons of the probability density function of the mixture of three normal distributions for a pixel and the probability density functions of the mixture of three normal distributions for spectral classes. The comparisons are made according to the distances between them. The discriminant function, which takes values on the interval \[0, 2], is defined as Hellinger distance. The decision rule is established according to the values of Hellinger distances. The values of the discriminant functions give extra information including spectral similarity and difference percentages in the comparisons. This clarifies the classification results and could help researchers interpret better the classification results of remotely-sensed multi-spectral data. 相似文献
110.
In this study, Na‐montmorillonite was organically modified with cetyltrimethylammoniumbromide (CTAB) and intercalated with in‐situ polymerized indene. Polyindene(PIn)/Organo‐MMT nanocomposites were obtained with three different compositions and coded as: K1: [PIn(94.5%)/O‐MMT(5.5%)], K2: [PIn(92.8%)/O‐MMT(7.2%)], and K3: [PIn(87.9%)/O‐MMT(12.1%)]. These nanocomposites were subjected to full characterization with various techniques. Electrokinetic studies were conducted to reveal the zeta (ζ)‐potential characteristics of the nanocomposites. ζ‐potentials of the materials were observed to decrease with increasing O‐MMT content. The cationic (CTAB) and anionic (sodium dodecylsulfate) surfactants were shifted the ζ‐potentials of the colloidal dispersions to more positive and more negative regions, respectively whereas nonionic surfactant (Triton X‐100) caused almost no change. The pH and temperature were observed to shift the ζ‐potential values of the nanocomposites to more negative and slightly more positive regions, respectively. With the addition of mono (NaCl), di (BaCl2) and three (AlCl3) valent salts, the ζ‐potential of the nanocomposites were shifted to more negative, more positive, and much more positive regions, respectively. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献