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排序方式: 共有688条查询结果,搜索用时 15 毫秒
81.
M. A. Yousry G. W. Sturm C. J. Feltz R. Noorossana 《Quality and Reliability Engineering International》1991,7(3):123-132
In this paper an empirical Bayes model is developed to monitor and analyse discrete data generated in a manufacturing process for printed circuit boards. A key feature of this analysis is the use of the current observation at time t and the posterior estimates of the distribution of the proportion nonconforming at time t – 1 to obtain a new, updated estimate of the posterior distribution at time t. The derived approach is widely applicable to statistical process control and provides a simple and fast algorithm for updating. 相似文献
82.
This paper introduces a new method for combining different object models. By determining a configuration of the models, which maximizes their mutual information, the proposed method creates a unified hypothesis from multiple object models on the fly without prior training. To validate the effectiveness of the proposed method, experiments are conducted in which human faces are detected and localized in images by combining different face models. 相似文献
83.
Linear matrix inequality formulation of spectral mask constraints with applications to FIR filter design 总被引:1,自引:0,他引:1
Davidson T.N. Zhi-Quan Luo Sturm J.F. 《Signal Processing, IEEE Transactions on》2002,50(11):2702-2715
The design of a finite impulse response (FIR) filter often involves a spectral "mask" that the magnitude spectrum must satisfy. The mask specifies upper and lower bounds at each frequency and, hence, yields an infinite number of constraints. In current practice, spectral masks are often approximated by discretization, but in this paper, we derive a result that allows us to precisely enforce piecewise constant and piecewise trigonometric polynomial masks in a finite and convex manner via linear matrix inequalities. While this result is theoretically satisfying in that it allows us to avoid the heuristic approximations involved in discretization techniques, it is also of practical interest because it generates competitive design algorithms (based on interior point methods) for a diverse class of FIR filtering and narrowband beamforming problems. The examples we provide include the design of standard linear and nonlinear phase FIR filters, robust "chip" waveforms for wireless communications, and narrowband beamformers for linear antenna arrays. Our main result also provides a contribution to system theory, as it is an extension of the well-known positive-real and bounded-real lemmas. 相似文献
84.
Rapid thermal chemical vapor deposition (RTCVD) is a competing technology for the growth of Si1?xGex strained-layer structures for the development of silicon-based heterojunctions. High-quality epitaxial films with growth temperatures as low as 600°C and 4.5 nm-period superlattices have been demonstrated without the use of ultrahigh-vacuum techniques. Narrow-bandgap-base heterojunction bipolar transistors made of Si/Si1?xGex/Si have been shown to have superior characteristics compared to all-silicon homojunction devices, and extend the scaling limits of bipolar transistors. Finally, RTCVD strained Si1?xGex films exhibit well-resolved band-edge photoluminescence—the first step on the way to developing silicon-based light-emitting devices. 相似文献
85.
A Pillay H Liu CY Chen B Holloway AW Sturm B Steiner SA Morse 《Canadian Metallurgical Quarterly》1998,25(8):408-414
PURPOSE: Psychosocial distress and patient attitude towards psychosocial support as well as the correlations with clinical and sociodemographic characteristics should be assessed. METHODS: The stress due to cancer was measured in a consecutive sample of tumor patients at the start of radiotherapy (n = 117) by use of the Hornheide Questionnaire. In addition, the interest of these patients in professional psychosocial support was assessed with the help of the Questionnaire for Psychosocial Support. RESULTS: Patients in the course of radiotherapy and patients with a poor prognosis and advanced disease were more strongly distressed. 32.7% of patients wished professional psychosocial support from the oncologist treating them, 40.6% of the patients wished support from the oncologist and additionally from a psychotherapist or social worker. Interest in professional psychosocial support correlated with the amount of distress, but not with sociodemographic variables. CONCLUSIONS: Results stress the importance of training programs for oncologists in order to improve their ability to detect psychosocial distress in cancer patients and to offer adequate emotional support to them. 相似文献
86.
Einfluß von Wärmedehnungen auf das Spannungs- und Dehnungsverhalten fester Körper und Formulierung der Spannungs- und Dehnungsbeziehungen in Matrizenform für ebene und axialsymmetrische Probleme. Überprüfung der Aussagemöglichkeiten des Verfahrens anhand von Anwendungsbeispielen. 相似文献
87.
K Herholz U Pietrzyk J Voges R Schr?der M Halber H Treuer V Sturm WD Heiss 《Canadian Metallurgical Quarterly》1993,79(6):853-858
To determine histological correlates of the variability of glucose consumption in astrocytomas, the authors performed positron emission tomography (PET) with 18F-2-fluoro-2-deoxy-D-glucose (FDG) and matched the PET scans three-dimensionally with computerized tomography scans obtained in a stereotactic frame before biopsy. Ten patients with astrocytomas of World Health Organization Grade 2 or 3 were studied; patients with glioblastomas, oligodendrogliomas, or oligoastrocytomas were excluded from the study to avoid any confounding effects of different cell types and necroses. In samples of pure tumor, glucose consumption correlated significantly with cell density, but not with nuclear polymorphism. It is concluded that tumor cell density is a major determinant of glucose consumption in astrocytomas. The use of PET with FDG may help to locate the highest cell density and thus improve the diagnostic yield of stereotactic biopsy. 相似文献
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