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61.
Interface trap generation in nMOS transistors during both stressing and post-stress periods under the conditions of oxide field (dynamic and dc) stress with FN injection is investigated with charge pumping technique. In contrast to the post-stress interface trap generation induced by hot carrier stress which is a logarithmical function of post-stress time, the post-stress interface trap generation induced by oxide-field stress with FN injection first increases with post-stress time but then becomes saturated. The mechanisms for the interface trap generation in both stressing and post-stress periods are described  相似文献   
62.
We present a near-optimal detection method for decoding codes appropriate to transmission using multiple transmit antennas in a fixed wireless environment. The method is a nontrivial generalization of maximum ratio combining. This reduces the decoding complexity at the expense of some sacrifice in performance  相似文献   
63.
This paper describes a joint collaboration program between a major large electric machine manufacturer and a petrochemical manufacturer to investigate the effectiveness of time- and frequency-domain techniques for the online monitoring of the health of high-voltage machine stator insulation systems. Information is given on the factory and site testing carried out, as well as on the analysis and discussion of the results. It is concluded that both techniques can be used in the petrochemical environment for general assessments, but the time domain technique is required if identification of specific locations of discharge sites is needed  相似文献   
64.
A new approach to 2-dimensional (2D) colour-image detection and matching using a modified version of the generalised Hough transform (GHT) is proposed. In the conventional GHT, the useful colour information existing in the input image and the relationship between each pixel and its neighbourhood are not used. Furthermore, lighting changes in the image are not usually considered. Therefore, the conventional GHT is seldom applied to colour images. In the proposed approach, lighting are removed using normalised colour values. Next, certain critical pixels of an input colour image whose neighbourhoods have larger variances of normalised colour values are extracted. For each critical pixel, a feature vector, which includes the normalised colour values of the pixel as well as those of the pixel's neighbours, is then constructed. A modified voting rule for the GHT is therefore proposed which is based on a similarity-measure function of the feature vectors. High maximum peaks in the cell array are searched finally as the result. The proposed method is robust for colour-image detection and matching in noisy, occlusive, and lighting-change environments, as demonstrated by experimental results  相似文献   
65.
The authors have developed a neural-digital computer-aided diagnosis system, based on a parameterized two-level convolution neural network (CNN) architecture and on a special multilabel output encoding procedure. The developed architecture was trained, tested, and evaluated specifically on the problem of diagnosis of lung cancer nodules found on digitized chest radiographs. The system performs automatic "suspect" localization, feature extraction, and diagnosis of a particular pattern-class aimed at a high degree of "true-positive fraction" detection and low "false-positive fraction" detection. In this paper, the authors aim at the presentation of the two-level neural classification method in reducing false-positives in their system. They employed receiver operating characteristics (ROC) method with the area under the ROC curve (A(z)) as the performance index to evaluate all the simulation results. The two-level CNN showed superior performance (A(z)=0.93) to the single-level CNN (A(z)=0.85). The proposed two-level CNN architecture is proven to be promising and to be extensible, problem-independent, and therefore, applicable to other medical or difficult diagnostic tasks in two-dimensional (2-D) image environments.  相似文献   
66.
Fast clustering process for vector quantisation codebook design   总被引:1,自引:0,他引:1  
Cheng  S.-M. Lo  K.-T. 《Electronics letters》1996,32(4):311-312
A fast clustering process is introduced to the generalised Lloyd algorithm for vector quantisation codebook design. Simulations show that the proposed codebook design method achieves significant saving in computational time and similar qualitative performance to that of the conventional full-search approach  相似文献   
67.
The small-signal output conductance of GaAs MESFETs on semi-insulating substrate is studied using two-dimensional numerical analysis. Frequency-, temperature-, and drain-bias-dependent behaviours of the output conductance are analysed. It is confirmed that the bulk EL2 traps contribute significantly to the low-frequency-dependent behavior of the output conductance. Devices with different background trap concentrations and acceptor concentrations were analyzed and compared. For devices with higher trap concentrations, the output conductance is lower but exhibits stronger frequency dependence  相似文献   
68.
Based on my experience as an engineer and educator, I believe that "engineering leadership" rather than "engineering management" should be the goal of engineers in key roles and the focus of their management education. I would also like to see programs in technical organizations led by engineering leaders rather than nontechnical managers. I believe that it is more beneficial to enhance the leadership potential of an engineer than to educate the nontechnical manager in technology.  相似文献   
69.
Rechargeable all‐solid‐state batteries will play a key role in many autonomous devices. Planar solid‐state thin film batteries are rapidly emerging but reveal several drawbacks, such as a relatively low energy density and the use of highly reactive metallic lithium. In order to overcome these limitations a new 3D‐integrated all‐solid‐state battery concept with significantly increased surface area is presented. By depositing the active battery materials into high‐aspect ratio structures etched in, for example silicon, 3D‐integrated all‐solid‐state batteries are calculated to reach a much higher energy density. Additionally, by adopting novel high‐energy dense Li‐intercalation materials the use of metallic Lithium can be avoided. Sputtered Ta, TaN and TiN films have been investigated as potential Li‐diffusion barrier materials. TiN combines a very low response towards ionic Lithium and a high electronic conductivity. Additionally, thin film poly‐Si anodes have been electrochemically characterized with respect to their thermodynamic and kinetic Li‐intercalation properties and cycle life. The Butler‐Vollmer relationship was successfully applied, indicating favorable electrochemical charge transfer kinetics and solid‐state diffusion. Advantageously, these new Li‐intercalation anode materials were found to combine an extremely high energy density with fast rate capability, enabling future 3D‐integrated all‐solid‐state batteries.  相似文献   
70.
A mobile medical information system (MMIS) is an integrated application (app) of traditional hospital information systems (HIS) which comprise a picture archiving and communications system (PACS), laboratory information system (LIS), pharmaceutical management information system (PMIS), radiology information system (RIS), and nursing information system (NIS). A dynamic resource allocation table is critical for optimizing the performance to the mobile system, including the doctors, nurses, or other relevant health workers. We have designed a smart dynamic resource allocation model by using the C4.5 algorithm and cumulative distribution for optimizing the weight of resource allocated for the five major attributes in a cooperation communications system. Weka is used in this study. The class of concept is the performance of the app, optimal or suboptimal. Three generations of optimization of the weight in accordance with the optimizing rate are shown.  相似文献   
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