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81.
In this paper, we have proposed some new numerical and semi-analytical methods for developing an equivalent three-layer model of an MQW waveguide. The waveguiding properties like effective index, field distribution, and fractional power within the core of the waveguide of these equivalent structures are compared with those of previously reported equivalent methods. These results are also compared with the results obtained from the exact multilayer analysis of the MQW waveguide. The waveguiding properties are accurately predicted by the semi-analytical method using variational analysis, and the computational effort is significantly reduced. The use of the three-layer equivalent is illustrated in obtaining an estimation of the waveguide losses and is used to study the effect of nonlinearity  相似文献   
82.
We have determined the nucleotide and encoded amino acid sequences of the capsid, membrane precursor, membrane, envelope, and nonstructural NS1 protein genes of a dengue-2 virus (D2-04) isolated from a patient in Hainan, China. The sequenced region contains a gene organization similar to that of other flaviviruses. The overall amino acid sequence similarity between D2-04 and other dengue-2 viruses is greater than 92%, whereas that between D2-04 and members of the other dengue serotypes is about 65%.  相似文献   
83.
84.
The Journal of Supercomputing - Multiple tasks arrive in the distributed systems that can be executed in either parallel or sequential manner. Before the execution, tasks are scheduled prioritywise...  相似文献   
85.
The Journal of Supercomputing - In this article, the authors suggested a rotation-invariant local binary pattern-based weighted generalized closest neighbor (RILBP-WGCN) method for HSI...  相似文献   
86.
Sharma  Shalini  Chou  Jerry 《The Journal of supercomputing》2021,77(10):10896-10920
The Journal of Supercomputing - Travelling salesman problem (TSP) is a graph problem that has been widely used in many applications, especially for transportation and logistics. Because TSP is a NP...  相似文献   
87.
Neural Computing and Applications - This work presents an efficient hybridized approach for the classification of electrocardiogram (ECG) samples into crucial arrhythmia classes to detect heartbeat...  相似文献   
88.
We propose a novel pose-invariant face recognition approach which we call Discriminant Multiple Coupled Latent Subspace framework. It finds the sets of projection directions for different poses such that the projected images of the same subject in different poses are maximally correlated in the latent space. Discriminant analysis with artificially simulated pose errors in the latent space makes it robust to small pose errors caused due to a subject’s incorrect pose estimation. We do a comparative analysis of three popular latent space learning approaches: Partial Least Squares (PLSs), Bilinear Model (BLM) and Canonical Correlational Analysis (CCA) in the proposed coupled latent subspace framework. We experimentally demonstrate that using more than two poses simultaneously with CCA results in better performance. We report state-of-the-art results for pose-invariant face recognition on CMU PIE and FERET and comparable results on MultiPIE when using only four fiducial points for alignment and intensity features.  相似文献   
89.
Experiments were performed on the superplastic Zn-22% Al eutectoid alloy to determine the contribution of grain boundary sliding at both low (35%) and high (235%) elongations. The tests were conducted at two different strain rates in the superplastic Region II, and the results show that, within the accuracy of the measurements, there is a large sliding contribution at both elongations. By taking detailed measurements of both the magnitude of the sliding offset and the type of interface, it is shown that the average offsets are generally a maximum at the Zn-Zn boundaries, there is less sliding at the Zn-Al interfaces, and the offsets are a minimum at the Al-Al boundaries. In addition, the distributions of the magnitudes of the sliding offsets are similar at both the low and high elongations. It is concluded that grain boundary sliding is an important deformation process in the superplastic Region II and that it remains important even when the elongation is very high. The nature of the results indicates also that experimental observations of the deformation behaviour in superplastic materials at low elongations (up to 50%) provide meaningful information on the behaviour at much higher (superplastic) elongations.On leave from Mechanical Engineering Department, Nanjing Aeronautical Institute, Nanjing, Jiang-su 210002, People's Republic of China.  相似文献   
90.
The creep properties of a commercial, single phase aIurnina have been determined in the temperature range of 1623 to 1723 K. The stress exponent,n, in the relationship n was determined to be 1.9 and the true activation energy was found to be 635 kJ mol–1. Normal primary stage creep transients were observed up to strains of 1%. At low stresses, steady-state conditions were not obtained due to the occurrence of concurrent grain growth. It is shown that the steady state creep results are consistent with the occurrence of an interface controlled diffusionaI creep mechanism.  相似文献   
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