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91.
Virtually all previous classifier models take vectors as inputs, performing directly based on the vector patterns. But it is highly necessary to consider images as matrices in real applications. In this paper, we represent images as second order tensors or matrices. We then propose two novel tensor algorithms, which are referred to as Maximum Margin Multisurface Proximal Support Tensor Machine (M3PSTM) and Maximum Margin Multi-weight Vector Projection Support Tensor Machine (M3VSTM), for classifying and segmenting the images. M3PSTM and M3VSTM operate in tensor space and aim at computing two proximal tensor planes for multisurface learning. To avoid the singularity problem, maximum margin criterion is used for formulating the optimization problems. Thus the proposed tensor classifiers have an analytic form of projection axes and can achieve the maximum margin representations for classification. With tensor representation, the number of estimated parameters is significantly reduced, which makes M3PSTM and M3VSTM more computationally efficient when handing the high-dimensional datasets than applying the vector representations based methods. Thorough image classification and segmentation simulations on the benchmark UCI and real datasets verify the efficiency and validity of our approaches. The visual and numerical results show M3PSTM and M3VSTM deliver comparable or even better performance than some state-of-the-art classification algorithms.  相似文献   
92.

Gallium doped ZnO (GZO) top electrode thickness dependence of resistive switching characteristic of GZO/ZnO2/ZnO/ITO transparent valence change memory device is investigated. The thickness of the GZO top electrode modulates the resistance of the pristine device. Devices made with thicker GZO layer have higher leakage current; thus, require higher current compliance. An excessively high current compliance leads to a device breakdown upon reset process. Conversely, a very low current compliance may form a tiny conducting filament and is difficult to rejuvenate after the rupture; thus, its cycle-to-cycle characteristic shows a decaying behavior. Nevertheless, transparent valence change devices with a stable endurance and sufficient memory window that operate at a moderate level of current compliance are successfully fabricated by employing an appropriate thickness of the top electrode. We suggest that a good switch-ability of transparent valence change memory devices are strongly affected by the thickness of the top electrode.

  相似文献   
93.
Tommy Newcomb 《硅谷》2005,(5):89-90
最近,许多Web站点开始在开发人员社区当中引起关注。这些站点独特之处在于,它们更像是桌面应用程序而非Web应用程序。当您与它们交互时,它们可以快速在洲览器显示无穷的信息而又无需重新加载页面。  相似文献   
94.
As part of a complex network of genome control, long regulatory RNAs exert significant influences on chromatin dynamics. Understanding how this occurs could illuminate new avenues for disease treatment and lead to new hypotheses that would advance gene regulatory research. Recent studies using the model fission yeast Schizosaccharomyces pombe (S. pombe) and powerful parallel sequencing technologies have provided many insights in this area. This review will give an overview of key findings in S. pombe that relate long RNAs to multiple levels of chromatin regulation: histone modifications, gene neighborhood regulation in cis and higher-order chromosomal ordering. Moreover, we discuss parallels recently found in mammals to help bridge the knowledge gap between the study systems.  相似文献   
95.
Diastereomers of the spiroacetal, 2,8-dimethyl-1,7-dioxaspiro [5.5]undecane, represent main components of the cephalic secretion from males of the solitary bee,Andrena wilkella. The major compound proved to be of high enantiomeric purity, showing (2S,6R,8S) configuration. Only the naturally occurring enantiomer attracted patrolling males in the field; its antipode was behaviorally inactive and in a racemic mixture did not inhibit response. The (E,Z) diastereomers were also found to be almost inactive. EAG studies gave the same result as the behavioral tests. The biological function of the spiroacetal is discussed in view of the evolution of the mating behavior inA. wilkella.  相似文献   
96.
97.
The broadband ISDN (BISDN) or integrated broadband communication (IBC) customer access connection (CAC) must meet a wide variety of technical and economic requirements in order to be competitive with dedicated network accesses and cope with the evolution of future services. Many proposals for broadband implementations are based on various service scenarios. Such scenarios may very well be applicable to certain user categories or at certain points in time. The CAC to be defined, however, has not to be based on one such scenario–but has to be able efficiently to support all the varying and evolving customer needs during a long period of time. In this paper the requirements are analysed and a CAC system concept fulfilling the basic requirements is put forward bearing in mind the interaction with relevant basic technology. A step-by-step evolution scenario for the BISDN/IBC network with emphasis on the CAC system introduction is outlined and finally some standardization issues are highlighted.  相似文献   
98.
A new multi-layer self-organizing map (MLSOM) is proposed for unsupervised processing tree-structured data. The MLSOM is an improved self-organizing map for handling structured data. By introducing multiple SOM layers, the MLSOM can overcome the computational speed and visualization problems of SOM for structured data (SOM-SD). Node data in different levels of a tree are processed in different layers of the MLSOM. Root nodes are dedicatedly processed on the top SOM layer enabling the MLSOM a better utilization of SOM map compared with the SOM-SD. Thus, the MLSOM exhibits better data organization, clustering, visualization, and classification results of tree-structured data. Experimental results on three different data sets demonstrate that the proposed MLSOM approach can be more efficient and effective than the SOM-SD.  相似文献   
99.
The purpose of this study was to determine the effectiveness of filial therapy as a method of prevention and intervention for immigrant Chinese families in Canada. Results of the analyses of covariance indicate that parents in the experimental group demonstrated a significant increase in empathic interaction with their children, a significant increase in acceptance of their children, a significant reduction of perceived stress related to parenting, and a significant reduction of perceived problems related to their children's behavior. Children of parents in the experimental group demonstrated a significant increase in self-concept. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
We present three methods for deriving water-leaving radiance L(w)(lambda) and remote-sensing reflectance using a hyperspectral tethered spectral radiometer buoy (HyperTSRB), profiled spectroradiometers, and Hydrolight simulations. Average agreement for 53 comparisons between HyperTSRB and spectroradiometric determinations of L(w)(lambda) was 26%, 13%, and 17% at blue, green, and red wavelengths, respectively. Comparisons of HyperTSRB (and spectroradiometric) L(w)(lambda) with Hydrolight simulations yielded percent differences of 17% (18%), 17% (18%), and 13% (20%) for blue, green, and red wavelengths, respectively. The differences can be accounted for by uncertainties in model assumptions and model input data (chlorophyll fluorescence quantum efficiency and the spectral chlorophyll-specific absorption coefficient for the red wavelengths, and scattering corrections for input ac-9 absorption data and volume scattering function measurements for blue wavelengths) as well as radiance measurement inaccuracies [largely differences in the depth of the L(u)(lambda, z) sensor on the HyperTSRB].  相似文献   
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