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81.
Hyunjung Shim Rolf Adelsberger James Dokyoon Kim Seon-Min Rhee Taehyun Rhee Jae-Young Sim Markus Gross Changyeong Kim 《The Visual computer》2012,28(12):1139-1151
This paper presents a multi-view acquisition system using multi-modal sensors, composed of time-of-flight (ToF) range sensors and color cameras. Our system captures the multiple pairs of color images and depth maps at multiple viewing directions. In order to ensure the acceptable accuracy of measurements, we compensate errors in sensor measurement and calibrate multi-modal devices. Upon manifold experiments and extensive analysis, we identify the major sources of systematic error in sensor measurement and construct an error model for compensation. As a result, we provide a practical solution for the real-time error compensation of depth measurement. Moreover, we implement the calibration scheme for multi-modal devices, unifying the spatial coordinate for multi-modal sensors. The main contribution of this work is to present the thorough analysis of systematic error in sensor measurement and therefore provide a reliable methodology for robust error compensation. The proposed system offers a real-time multi-modal sensor calibration method and thereby is applicable for the 3D reconstruction of dynamic scenes. 相似文献
82.
Levi Valgaerts Andrés Bruhn Markus Mainberger Joachim Weickert 《International Journal of Computer Vision》2012,96(2):212-234
There are two main strategies for solving correspondence problems in computer vision: sparse local feature based approaches
and dense global energy based methods. While sparse feature based methods are often used for estimating the fundamental matrix
by matching a small set of sophistically optimised interest points, dense energy based methods mark the state of the art in
optical flow computation. The goal of our paper is to show that this separation into different application domains is unnecessary
and can be bridged in a natural way. As a first contribution we present a new application of dense optical flow for estimating
the fundamental matrix. Comparing our results with those obtained by feature based techniques we identify cases in which dense
methods have advantages over sparse approaches. Motivated by these promising results we propose, as a second contribution,
a new variational model that recovers the fundamental matrix and the optical flow simultaneously as the minimisers of a single
energy functional. In experiments we show that our coupled approach is able to further improve the estimates of both the fundamental
matrix and the optical flow. Our results prove that dense variational methods can be a serious alternative even in classical
application domains of sparse feature based approaches. 相似文献
83.
Hussein Muzahim Aziz Markus Fiedler H?kan Grahn Lars Lundberg 《Multimedia Systems》2012,18(3):251-262
Streaming video over a wireless network faces several challenges such as high packet error rates, bandwidth variations, and delays, which could have negative effects on the video streaming and the viewer will perceive a frozen picture for certain durations due to loss of frames. In this study, we propose a Time Interleaving Robust Streaming (TIRS) technique to significantly reduce the frozen video problem and provide a satisfactory quality for the mobile viewer. This is done by reordering the streaming video frames as groups of even and odd frames. The objective of streaming the video in this way is to avoid the losses of a sequence of neighbouring frames in case of a long sequence interruption. We evaluate our approach by using a user panel and mean opinion score (MOS) measurements; where the users observe three levels of frame losses. The results show that our technique significantly improves the smoothness of the video on the mobile device in the presence of frame losses, while the transmitted data are only increased by almost 9% (due to reduced time locality). 相似文献
84.
85.
Questions S. L. Bem's (see record 1983-21087-001) definition of a gender schema and argues that male and female sex-typed individuals do not have equivalent gender schemata. The high-androgynous individuals are the only ones for whom both masculinity and femininity are equally available and who might be properly termed "gender schematic." (6 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Markus Lazar Charalampos Anastassiadis 《International Journal of Engineering Science》2006,44(20):1571-1582
In this paper, following Noether’s theorem we investigate Lie point symmetries of linear theories of microstretch elasticity and micromorphic elasticity. We restrict our consideration to isotropic, compatible and homogeneous materials. Conservation and balance laws are derived, thereby extending results from micropolar elasticity. 相似文献
87.
Algorithms for Moving Objects Databases 总被引:8,自引:0,他引:8
88.
The existence of spectro-temporal receptive fields and evidence for population coding in auditory cortex motivate the development
of such models, that explicitly operate in the time-frequency domain and are based on a pulsed neural network. In presenting
such a model, a formal connection of the fields of Time Frequency Analysis and Pulsed Neural Networks is established. The
resulting neural time-frequency signal representation is shown to be representable as a signal-dependent overcomplete dictionary.
It is derived from neural population coding. Signal decomposition and filtering effects are presented, indicating obvious
technical applications of the proposed model.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
89.
Frey B Hartmann M Herrmann M Meyer-Pittroff R Sommer K Bluemelhuber G 《Microscopy research and technique》2006,69(2):65-72
High hydrostatic pressure (HHP) becomes more and more interesting for life science research, since it can be employed to inactivate various cells. To directly monitor "cells under pressure," the development of an optical high-pressure chamber is required. Therefore, an optical pressure chamber that can be used for up to 300 MPa was constructed. This chamber has already been described as a tool for in situ observation of dynamic changes of microscopic structures in bright field as well as phase contrast. In combination with an inverted microscope, we obtained brilliant microscopic color pictures with an optical resolution more than 0.56 microm. Here, we demonstrate the capabilities of the HHP cell, in combination with epifluorescence microscopy. Using a nonadherent human B-cell line (Raji, ATCC CCL 86), stained with the fluorescent dyes propidium iodide, Hoechst 33342, or dihexyloxacarbocyanine iodide, we were able to show that the system is suitable to perform fluorescence microscopic analyses, with pressures up to 300 MPa, with viable mammalian cells. 相似文献
90.
According to classical theories, automatic processes are autonomous and independent of higher level cognitive influence. In contrast, the authors propose that automatic processing depends on attentional sensitization of task-congruent processing pathways. In 3 experiments, the authors tested this hypothesis with a modified masked semantic priming paradigm during a lexical decision task by measuring event-related potentials (ERPs): Before masked prime presentation, participants attended an induction task either to semantic or perceptual stimulus features designed to activate a semantic or perceptual task set, respectively. Semantic priming effects on the N400 ERP component, an electrophysiological index of semantic processing, were obtained when a semantic task set was induced immediately before subliminal prime presentation, whereas a previously induced perceptual task set attenuated N400 priming. Across experiments, comparable results were obtained regardless of the difficulty level and the verbal or nonverbal nature of the induction tasks. In line with the proposed attentional sensitization model, unconscious semantic processing is enhanced by a semantic and attenuated by a perceptual task set. Hence, automatic processing of unconscious stimuli is susceptible to top-down control for optimizing goal-related information processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献