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61.
Amit Bermanis Amir Averbuch Ronald R. Coifman 《Applied and Computational Harmonic Analysis》2013,34(1):15-29
We introduce a multiscale scheme for sampling scattered data and extending functions defined on the sampled data points, which overcomes some limitations of the Nyström interpolation method. The multiscale extension (MSE) method is based on mutual distances between data points. It uses a coarse-to-fine hierarchy of the multiscale decomposition of a Gaussian kernel. It generates a sequence of subsamples, which we refer to as adaptive grids, and a sequence of approximations to a given empirical function on the data, as well as their extensions to any newly-arrived data point. The subsampling is done by a special decomposition of the associated Gaussian kernel matrix in each scale in the hierarchical procedure. 相似文献
62.
Yogendra K. Gautam Amit K. ChawlaRajan Walia R.D. AgrawalRamesh Chandra 《Applied Surface Science》2011,257(14):6291-6295
Structural and optical properties of pure Mg thin film coated with Pd have been investigated. Pd-capped Mg thin films had been prepared by DC magnetron sputtering. This work presents an ex situ study on hydrogenation and dehydrogenation kinetics of Pd/Mg films at different conditions using XRD, AFM and optical spectrophotometer. We have succeeded to load thin films of Mg to MgH2 at normal temperature and normal pressure of hydrogen gas. In hydrogenation, α-MgH2 phase of magnesium hydride was observed in hydrogenated films at 200 °C and γ-MgH2 at 250 °C respectively. The desorption kinetics in vacuum also revealed the phase transformation α-MgH2 to γ-MgH2. A reflectance change was observed in hydrogenated films in comparison of as deposited thin film. Hydrogenated (H loaded) samples were observed partially transparent in comparison of as deposited. 相似文献
63.
A new integrated scheme based on resource-reservation and adaptive network flow routing to alleviate contention in optical burst switching networks is proposed. The objective of the proposed scheme is to reduce the overall burst loss in the network and at the same time to avoid the packet out-of-sequence arrival problem. Simulations are carried out to assess the feasibility of the proposed scheme. Its performance is compared with that of contention resolution schemes based on conventional routing. Through extensive simulations, it is shown that the proposed scheme not only provides significantly better burst loss performance than the basic equal proportion and hop-length based traffic routing algorithms, but also is void of any packet re-orderings. 相似文献
64.
A novel optical burst switching (OBS) high speed network architecture has been proposed. To verify its feasibility and evaluate its performance, just-enough-time (JET) signaling has been considered as a high performance protocol. In the proposed architecture, to avoid burst losses, firstly, a short-prior- confirmation-packet (SPCP) is sent over the control channel that simulates the events that the actual packet will experience. Once SPCP detects a drop at any of the intermediate nodes, the actual packet is not sent but the process repeats. In order to increase network utilization, cost effectiveness and to overcome some limitations of conventional OBS, inherent codes (e.g., orthogonal optical codes (OOC)), which are codified only in intensity, has been used. Through simulations, it shows that a decrease in burst loss probability, cost effectiveness and a gain in processing time are obtained when optical label processing is used as compared with electronic processing. 相似文献
65.
66.
Hanna TA Ghosh AK Ibarra C Zakharov LN Rheingold AL Watson WH 《Inorganic chemistry》2004,43(24):7567-7569
Molybdenum monooxo compoundsMoO(OAr)4-nCln (n=0-2, Ar=2,6-Me2C6H3 or 2,6-i-Pr2C6H3) have been synthesized starting from the dioxo precursor MoO2Cl2. The complexes are characterized spectroscopically and by X-ray diffraction. The formation mechanism likely involves phenol precoordination followed by addition across the Mo=O bond. 相似文献
67.
Novel enediynyl amino acids and peptides 3 and 5-8 were synthesized and their thermal reactivity towards Bergman cyclization studied and compared with the earlier reported amino acid 4, which demonstrated, for the first time, the effect of H-bonding and electrostatic interactions in lowering the activation energy of Bergman cyclization. 相似文献
68.
A lot of importance has been attached to the testing phase of the Software Development Life Cycle (SDLC). It is during this phase it is checked whether the software product meets user requirements or not. Any discrepancies that are identified are removed. But testing needs to be monitored to increase its effectiveness. Software Reliability Growth Models (SRGMs) that specify mathematical relationships between the failure phenomenon and time have proved useful. SRGMs that include factors that affect failure process are more realistic and useful. Software fault detection and removal during the testing phase of SDLC depend on how testing resources (test cases, manpower and time) are used and also on previously identified faults. With this motivation a Non-Homogeneous Poisson Process (NHPP) based SRGM is proposed in this paper which is flexible enough to describe various software failure/reliability curves. Both testing efforts and time dependent fault detection rate (FDR) are considered for software reliability modeling. The time lag between fault identification and removal has also been depicted. The applicability of our model is shown by validating it on software failure data sets obtained from different real software development projects. The comparisons with established models in terms of goodness of fit, the Akaike Information Criterion (AIC), Mean of Squared Errors (MSE), etc. have been presented. 相似文献
69.
Danne Ashruba B. Choudhari Amit S. Sarkar Dhiman Sangshetti Jaiprakash N. Khedkar Vijay M. Shingate Bapurao B. 《Research on Chemical Intermediates》2018,44(10):6283-6310
Research on Chemical Intermediates - The synthesis of a new series of triazole-biscoumarin conjugates by using a molecular hybridization approach is described. The newly synthesized compounds... 相似文献
70.
Amit Deshpande Rahul Jain T. Kavitha Satyanarayana V. Lokam Jaikumar Radhakrishnan 《Random Structures and Algorithms》2005,27(3):358-378
An error‐correcting code is said to be locally decodable if a randomized algorithm can recover any single bit of a message by reading only a small number of symbols of a possibly corrupted encoding of the message. Katz and Trevisan 12 showed that any such code C : {0, 1}n → Σm with a decoding algorithm that makes at most q probes must satisfy m = Ω((n/log |Σ|)q/(q?1)). They assumed that the decoding algorithm is non‐adaptive, and left open the question of proving similar bounds for adaptive decoders. We show m = Ω((n/log |Σ|)q/(q?1)) without assuming that the decoder is nonadaptive. © 2005 Wiley Periodicals, Inc. Random Struct. Alg., 2005 相似文献