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151.
Matching Trajectories of Anatomical Landmarks Under Viewpoint,Anthropometric and Temporal Transforms
Alexei Gritai Yaser Sheikh Cen Rao Mubarak Shah 《International Journal of Computer Vision》2009,84(3):325-343
An approach is presented to match imaged trajectories of anatomical landmarks (e.g. hands, shoulders and feet) using semantic
correspondences between human bodies. These correspondences are used to provide geometric constraints for matching actions
observed from different viewpoints and performed at different rates by actors of differing anthropometric proportions. The
fact that the human body has approximate anthropometric proportion allows innovative use of the machinery of epipolar geometry
to provide constraints for analyzing actions performed by people of different sizes, while ensuring that changes in viewpoint
do not affect matching. In addition, for linear time warps, a novel measure, constructed only from image measurements of the
locations of anatomical landmarks across time, is proposed to ensure that similar actions performed at different rates are
accurately matched as well. An additional feature of this new measure is that two actions from cameras moving at constant
(and possibly different) velocities can also be matched. Finally, we describe how dynamic time warping can be used in conjunction
with the proposed measure to match actions in the presence of nonlinear time warps. We demonstrate the versatility of our
algorithm in a number of challenging sequences and applications, and report quantitative evaluation of the matching approach
presented. 相似文献
152.
153.
随着网络规模的增大和通信技术的发展,网络安全、金融和交通等领域已经开始利用事件流技术实现其业务数据的处理及分析。该文针对这些领域复杂的网络环境为事件流引擎设计并实现了一种基于组件技术的通信框架,可以灵活地集成多种通信组件以应对不同的通信环境,并且通过嵌入Esper引擎提供统一的语义封装解析和高性能的事件流业务处理。 相似文献
154.
Girish Shah 《中国宝玉石》2018,(2)
正在印度文化中,钻石在3000年的时间长河里占据着稀罕珍贵又非凡的地位。作为一种象征着勇气和生命力的法宝,钻石深受皇宫贵族的喜爱而常常被佩戴于身上。爱美钻石集团成立于半世纪以前。多年来,秉持创业之初对于钻石的热爱,爱美钻石集团成为专门为行业内高端珠宝品牌公司提供美钻的供应商,并享誉全球。得益于我们多年来对于钻石制造工艺的精益求精,如今我们终于有能力推出一款拥有完美切工 相似文献
155.
O.N. Donkor N.P. Shah V. Apostolopoulos T. Vasiljevic 《International Dairy Journal》2010,20(6):373-385
The prevalence of allergic disorders may stem from reduced microbial exposure during childhood. Allergic disorders (rhinitis, asthma, atopic dermatitis) result from a systemic inflammatory reaction triggered by Th2-cell-mediated immune responses against ‘innocuous’ environmental antigens. Initial interpretations proposed an immune deviation of allergen-specific responses from a Th1 to a Th2 profile resulting from reduced production of interleukin-12 and interferons by natural immune cells stimulated by bacterial products. Both stereotypical and selective responses of innate host cells are invoked by different microorganisms. Early in an infection, pathogens can therefore imprint their ‘signatures’ on antigen-presenting cells and subsequent immune responses. This interaction between microorganisms and enterocytes is important for the controlled production of cytokines and chemokines. Some probiotic microorganisms can modulate the in vitro expression of pro- and anti-inflammatory cytokines in a strain-dependent manner, probably skew the immune response towards Th1 phenotype and play an important role in allergy prevention. 相似文献
156.
This work is aimed at the development of a state observer (steady state Kalman filter) for a multivariable system with unknown time delays, which is subjected to unmeasured disturbances. To design such a filter, we explore the feasibility of capturing system dynamics using generalized orthonormal basis filters (GOBF). A two step identification procedure is proposed by exploiting the fact that the GOBF based models have output error structure. The deterministic component of the model is identified in the first step and used to compute a residual signal. In the second step, a filter that whitens the residuals is estimated using GOBF and combined with the deterministic component. A minimal order state realization of the innovation form of the state model is then generated from this high order model using realization based sub-space based state space (4SID) identification algorithm. When time delays are not known a-priori, the similarity between GOBF and Pade approximation is used to estimates time delay matrix directly from multivariate data. The efficacy of the proposed modeling technique is demonstrated by carrying out simulation studies on the benchmark Shell control problem and experimental evaluation on a stirred tank heater (STH) system. From the analysis of simulation and experimental results, it can be inferred that the proposed approach produces fairly accurate estimates of the time delay matrix and the deterministic and stochastic components of the dynamic model. 相似文献
157.
R.B. Gopaluni H. Raghavan R.S. Patwardhan S.L. Shah G.A. Dumont 《Journal of Process Control》2006,16(9):903-912
A new identification method for single-input–single-output delay dominant recycle systems is presented in this paper. Identification of recycle systems is similar to that of closed loop systems. However, identification of recycle systems poses certain challenges in that the input-equivalent signal in the closed loop identification is not available for recycle systems. Therefore, special identification routines are required to ensure consistency of recycle and forward models. It is shown that consistent estimates of delay dominant recycle systems can be obtained by treating a delayed output as one of the inputs. Asymptotic variance expressions for the estimates of forward and recycle models are provided. These are then used in designing an optimal excitation signal for recycle systems. The results are illustrated through an industrial example. 相似文献
158.
We report the uniform planar anchoring of thermotropic liquid crystals on films of bovine serum albumin (BSA) covalently immobilized on the surface of glass microscope slides and mechanically rubbed using a cloth. The azimuthal orientations of the liquid crystals were measured to be parallel to the direction of rubbing. Following immersion and removal of these rubbed films of BSA from aqueous solutions containing either BSA, fibrinogen, lysozyme, anti-FITC immunoglobulin G (IgG), or antistreptavidin IgG, we measured liquid crystals placed onto these surfaces to largely retain their uniform alignment. In contrast, following immersion of a rubbed film of BSA into an aqueous solution of anti-BSA IgG, we observed liquid crystals on these surfaces to assume nonuniform orientations. We conclude that specific binding of anti-BSA IgG to the film of rubbed BSA erased anisotropy induced within the film of BSA by rubbing. This result suggests that the spatial scale of anisotropy within the rubbed film of BSA is comparable to or smaller than the size of the IgG molecule. Because the anisotropy within a rubbed film of a protein can be erased by specific binding of a second protein, we believe these types of substrates (rubbed films of proteins) have the potential to be useful in a variety of label-free biomolecular assays where specific binding of a target species to its ligand can be imaged through observation of the optical appearance of liquid crystal placed onto the surface. 相似文献
159.
D. G. Kuberkar N. A. Shah M. R. Gonal R. Prasad R. G. Kulkarni 《Journal of Superconductivity》2000,13(1):37-40
It has been reported that, by adding equal amounts of CaO and CuO to non superconducting La3Ba3Cu6O
z
(La-336), a series of superconductors with nominal compositions La3Ca
y
Ba3Cu6+y
O
z
were prepared with maximum Ton
c 80K. Similar studies on addition of CaO and CuO in nonsuperconducting LaBaCu2O
z
(La-112) resulted into superconducting LaCaBaCu3O
z
(La-1113). To date no attempt has been made to synthesize La2CaBa2Cu5O
z
(La-2125) superconducting phase by addition of CaO and CuO to non superconducting La2Ba2Cu4O
z
(La-224) system. Also no reports are published to study the effect of replacing larger La3+-ions (1.01Å) by smaller rare earth ions viz Y3+(0.89Å), Er3+(0.91Å), Gd3+(0.91Å) on the structural and superconducting properties of (La2–x
R
x
)Ba2(Ca
y
Cu4+y
)O
z
(LRBCaC); 0.0 x 0.5; y=2x system. In this paper, we report the method of synthesis, structural and superconducting property characterization using X-ray diffraction, oxygen content measurements using iodometry, resistivity measurements using d.c. four probe technique and a.c. susceptibility measurements in the temperature range RT to 15K. Also a comparative study, on the evolution of superconducting phase with Ca-concentration for different rare earth substitutions for LRBCaC system in the context of hole doping mechanism, is carried out. 相似文献
160.
A simple and novel interferometric setup for wave-front testing that uses a cross slit is described. In this method, the test beam illuminates a cross slit placed at the front focal plane of a Fourier lens. It selects two orthogonal slices from the test beam, and the interference of these two beams is observed at a slightly defocused plane near the back focal plane. Fringes of different conical forms (circular, elliptical, or hyperbolic) so obtained can be used for testing a coherent wave front in general. The theory, supported by some experimental results, is presented. An application of the method to the study of the nature of asymmetry in the beam profile of a semiconductor diode laser beam is demonstrated. 相似文献