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81.
82.
故障现象:制冷正常,但制热时烧熔丝。分析与检测:该空调安装好后,试机时只试了制冷状态,制冷工作正常,却未进行制热试机。后来用户想试一下制热,拨到制热挡,熔断器一开机就跳闸,等合上闸后整机就无任何反应了。最初分析也许是巧合,检查主控板上的熔丝已经烧了,随即更换上了一块线路板,试机制冷正常,但在制热状态立刻烧熔断,判断制热存在严重短路现象。即然制冷正常,制热状态只多一个四通阀线圈用电,检查室外机的接线,原来是安装工错将三跟导线中的黄线接到了地上。 相似文献
83.
Tony Armstrong 《今日电子》2006,(10):38-39,41
就由电池供电并以微硬盘(HDD)作为主要存储介质的手持产品而言,目前有3种市场驱动因素汇聚在一起,可能导致在这些便携式产品的电池工作时间方面产生极大的突破。这类便携式产品包括便携式播放器(PMP)、MP3播放器、数码相机(DSC)、数字录像机(DVR)、智能电话和GPS系统等。 相似文献
84.
Error Analysis for Image Inpainting 总被引:1,自引:0,他引:1
Image inpainting refers to restoring a damaged image with missing information. In recent years, there have been many developments
on computational approaches to image inpainting problem [2, 4, 6, 9, 11–13, 27, 28]. While there are many effective algorithms
available, there is still a lack of theoretical understanding on under what conditions these algorithms work well. In this
paper, we take a step in this direction. We investigate an error bound for inpainting methods, by considering different image
spaces such as smooth images, piecewise constant images and a particular kind of piecewise continuous images. Numerical results
are presented to validate the theoretical error bounds.
Tony F. Chan received the B.S. degree in engineering and the M.S. degree in aerospace engineering in 1973, from the California Institute
of Technology, and the Ph.D. degree in computer science from Stanford University in 1978.
He is Professor of Mathematics and currently also Dean of the division of Physical science at University of California, Los
Angeles, where he has been a Professor since 1986. His research interests include mathematical and computational methods in
image processing, multigrid, domain decomposition algorithms, iterative methods, Krylov subspace methods, and parallel algorithms.
Sung Ha Kang received the Ph.D. degree in mathematics in 2002, from University of California, Los Angeles, and currently is Assistant
Professor of Mathematics at University of Kentucky since 2002. Her research interests include mathematical and computational
methods in image processing and computer vision. 相似文献
85.
Total Variation Wavelet Inpainting 总被引:6,自引:0,他引:6
Tony F. Chan Jianhong Shen Hao-Min Zhou 《Journal of Mathematical Imaging and Vision》2006,25(1):107-125
We consider the problem of filling in missing or damaged wavelet coefficients due to lossy image transmission or communication.
The task is closely related to classical inpainting problems, but also remarkably differs in that the inpainting regions are
in the wavelet domain. New challenges include that the resulting inpainting regions in the pixel domain are usually not geometrically
well defined, as well as that degradation is often spatially inhomogeneous. We propose two related variational models to meet
such challenges, which combine the total variation (TV) minimization technique with wavelet representations. The associated
Euler-Lagrange equations lead to nonlinear partial differential equations (PDE’s) in the wavelet domain, and proper numerical
algorithms and schemes are designed to handle their computation. The proposed models can have effective and automatic control
over geometric features of the inpainted images including sharp edges, even in the presence of substantial loss of wavelet
coefficients, including in the low frequencies. Existence and uniqueness of the optimal inpaintings are also carefully investigated.
Research supported in part by grants ONR-N00014-03-1-0888, NSF DMS-9973341, DMS-0202565 and DMS-0410062, and NIH contract
P 20 MH65166. 相似文献
86.
Backpropagation, similar to most learning algorithms that can form complex decision surfaces, is prone to overfitting. This
work presents classification-based objective functions, an approach to training artificial neural networks on classification
problems. Classification-based learning attempts to guide the network directly to correct pattern classification rather than
using common error minimization heuristics, such as sum-squared error (SSE) and cross-entropy (CE), that do not explicitly
minimize classification error. CB1 is presented here as a novel objective function for learning classification problems. It
seeks to directly minimize classification error by backpropagating error only on misclassified patterns from culprit output
nodes. CB1 discourages weight saturation and overfitting and achieves higher accuracy on classification problems than optimizing
SSE or CE. Experiments on a large OCR data set have shown CB1 to significantly increase generalization accuracy over SSE or
CE optimization, from 97.86% and 98.10%, respectively, to 99.11%. Comparable results are achieved over several data sets from
the UC Irvine Machine Learning Database Repository, with an average increase in accuracy from 90.7% and 91.3% using optimized
SSE and CE networks, respectively, to 92.1% for CB1. Analysis indicates that CB1 performs a fundamentally different search
of the feature space than optimizing SSE or CE and produces significantly different solutions.
Editor: Risto Miikkulainen 相似文献
87.
88.
A sample deposition device has been constructed and optimized for interfacing CEC and capillary LC columns to MALDI mass spectrometry. For CEC analysis, the device is composed of an inlet buffer reservoir and an outlet buffer reservoir connected to a matrix reservoir through a connection sleeve. The matrix reservoir is connected to a deposition capillary via another connection sleeve. CEC eluent is transported to the matrix reservoir via a capillary that is connected to the deposition capillary by the connection sleeve inside the matrix reservoir. This connection sleeve also acts as a mixing chamber, allowing the CEC eluent to be mixed with matrix prior to deposition. Complex glycan mixtures can be separated by CEC using hydrophilic-phase monolithic columns, with capillary eluent being deposited on a standard MALDI plate along with a suitable matrix solution. Thousands of discrete, highly homogeneous dots can be generated for a subsequent mass spectrometric analysis. With minor modifications, this device is also applicable to capillary LC of peptides using gradient elution. In this configuration, the outlet of the LC column is connected to a deposition capillary inside a matrix reservoir through a connection sleeve that allows mixing of the LC effluent with an appropriate matrix. The device has been evaluated with the tryptic digests of proteins. 相似文献
89.
Mandana?Ebadian?Dehkordi Nasser?SherkatEmail author Tony?Allen 《International Journal on Document Analysis and Recognition》2003,6(1):55-74
This paper describes an independent handwriting style classifier that has been designed to select the best recognizer for a given style of writing. For this purpose a definition of handwriting legibility has been defined and a method implemented that can predict this legibility. The technique consists of two phases. In the feature-extraction phase, a set of 36 features is extracted from the image contour. In the classification phase, two nonparametric classification techniques are applied to the extracted features in order to compare their effectiveness in classifying words into legible, illegible, and middle classes. In the first method, a multiple discriminant analysis (MDA) is used to transform the space of extracted features (36 dimensions) into an optimal discriminant space for a nearest mean based classifier. In the second method, a probabilistic neural network (PNN) based on the Bayes strategy and nonparametric estimation of probability density function is used. The experimental results show that the PNN method gives superior classification results when compared with the MDA method. For the legible, illegible, and middle handwriting the method provides 86.5% (legible/illegible), 65.5% (legible/middle), and 90.5% (middle/illegible) correct classification for two classes. For the three-class legibility classification the rate of correct classification is 67.33% using a PNN classifier.Received: 6 September 2002, Accepted: 19 September 2002, Published online: 6 June 2003 相似文献
90.
We present experimental measurements of the C K-ELNES of high temperature pyrolysed graphite and related crystalline materials as a function of collection angle and sample tilt. These results together with a corresponding theoretical analysis indicate that the so-called "magic angle" for EELS measurements of an anisotropic crystal such as graphite, where spectra are independent of sample orientation, is approximately two times the characteristic scattering angle. We briefly discuss the implications of this result for the experimental measurement of anisotropic structures, including interfaces, as well as for the detailed modelling of ELNES structures using advanced electronic structure calculations. 相似文献