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91.
Applied Intelligence - Measuring the spread of disease during a pandemic is critically important for accurately and promptly applying various lockdown strategies, so to prevent the collapse of the...  相似文献   
92.
The temperature dependence of the thermoelectric power of calcium substituted YBa2–x Ca x Cu3O7– pellets with 0x1.5 is presented between 60 K and 300 K. A metal–insulator transition was reported earlier by us in this system and was attributed to the ionic size-dependent localization effect. While the sign of thermoelectric power of all the calcium substituted samples was found to be positive, its magnitude increases significantly with calcium content in YBCO. The normal state thermoelectric power data of substituted YBa2–x Ca x Cu3O7– (0x1.5) are discussed in light of a two-band model originally proposed by Gottwick et al. for heavy fermion systems and later modified by Forro et al.  相似文献   
93.
We study stochastic stability of centralized Kalman filtering for linear time-varying systems equipped with wireless sensors. Transmission is over fading channels where variable channel gains are counteracted by power control to alleviate the effects of packet drops. We establish sufficient conditions for the expected value of the Kalman filter covariance matrix to be exponentially bounded in norm. The conditions obtained are then used to formulate stabilizing power control policies which minimize the total sensor power budget. In deriving the optimal power control laws, both statistical channel information and full channel information are considered. The effect of system instability on the power budget is also investigated for both these cases.  相似文献   
94.
Multimedia Tools and Applications - Automated segmentation has an essential role in detecting several diseases, such as skin lesions. In segmentation, the active contour (AC) is an efficient method...  相似文献   
95.
7,8-Dichloro-1,2,3,4-tetrahydroisoquinoline (DCTQ) (50 mg/kg i.p.) antagonized the inactivation of MAO by pargyline as measured by direct enzyme assays in brain homogenates and by accumulation of hypothalamic catecholamines. These findings lend credence to the earlier interpretation that changes in brain concentrations of biogenic amines and their metabolites in DCTQ-treated rats were due at least in part to MAO inhibition.  相似文献   
96.
Issues related to the automated identification and elimination of the adverse influence of small geometric model features on the quality of automatically generated meshes, using local mesh modification operators, are addressed. The definition of mesh validity with respect to the geometric model is extended to include multiple mesh entity classifications. Checks based on mesh topology are used to ensure no dimensional reductions in the locally modified mesh. Example geometric models of varied complexity containing small geometric features are used to demonstrate the ability of presented procedures to improve mesh quality in terms of aspect ratio and small angle metrics.  相似文献   
97.

Multi-level thresholding is a helpful tool for several image segmentation applications. Evaluating the optimal thresholds can be applied using a widely adopted extensive scheme called Otsu’s thresholding. In the current work, bi-level and multi-level threshold procedures are proposed based on their histogram using Otsu’s between-class variance and a novel chaotic bat algorithm (CBA). Maximization of between-class variance function in Otsu technique is used as the objective function to obtain the optimum thresholds for the considered grayscale images. The proposed procedure is applied on a standard test images set of sizes (512 × 512) and (481 × 321). Further, the proposed approach performance is compared with heuristic procedures, such as particle swarm optimization, bacterial foraging optimization, firefly algorithm and bat algorithm. The evaluation assessment between the proposed and existing algorithms is conceded using evaluation metrics, namely root-mean-square error, peak signal to noise ratio, structural similarity index, objective function, and CPU time/iteration number of the optimization-based search. The results established that the proposed CBA provided better outcome for maximum number cases compared to its alternatives. Therefore, it can be applied in complex image processing such as automatic target recognition.

  相似文献   
98.
Neural Computing and Applications - Cost and physical constraints in the engineering applied problems obligate finding the best results that global optimization algorithms cannot realize. For...  相似文献   
99.
Through our experience in synthesis, validation, test, and integration of the picoJava processor core in a system-on-chip (SoC) design we point out the challenges faced and issues to address in efficient reuse of a soft core  相似文献   
100.
Wave-equation-based forward modelling using explicit finite-difference methods is a standard technique for calculating synthetic seismograms. The stability criterion restricts the size of the time step. In this paper a predictor–corrector method for solving the wave equation is described which allows the use of a larger time step. A stability analysis of the method is also carried out. Parallel implementation of the algorithm is described for a distributed computing environment which makes use of MPI and PVM message passing calls for communication between processors.  相似文献   
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