A lightweight trust management algorithm based on subjective logic for interconnected cloud computing environments

The Journal of Supercomputing - The interconnected cloud computing paradigm is gaining considerable attention as a fundamental emerging model of cloud computing. It allows a wide range of...     

Efficient detection of delamination in multilayered structures using ultrasonic guided wave EMATs

This paper presents an efficient method for the detection of delamination using a combined technology of ultrasonic guided wave and electromagnetic acoustic transducer (EMAT). The material for inspection studied in this paper is a three-layered brass/copper/brass metal composite for coin stocks. We first observed a cyclic behavior of wave sensitivity to delamination width in the experiment. This observation is then confirmed with finite element simulation. We found out that the cyclic behavior is related to the phase velocity of the converted wave modes in the two subsystems after delamination. To compensate for the cyclic behavior, two wave modes are used in an industrial inspection system to ensure effective detection of delamination in the composite sample. The inspection speed achieved with this EMAT inspection system is 1.8 m²/s.     

Ferromagnetism in Rutile Structure Cr Doped VO<Subscript>2</Subscript> Thin Films Prepared by Reactive-Bias Target Ion Beam Deposition

First generation spintronics has entered the mainstream of information technology through its utilization of the magnetic tunnel junction in applicable devices such as read head sensors for hard disk drives and magnetic random access memory. The future of spintronic devices requires next generation spintronic materials (Wolf et al. in IBM J. Res. Dev. 9:101, [2006]). Here we report on the structural, transport, and magnetic characteristics of V_1−x Cr _x O₂ (0.1≤x≤0.2) thin films deposited on (001) Al₂O₃ substrates. We show that the metal-insulator transition of VO₂ is suppressed and the rutile structure is stable down to 100 K. The films are remarkably smooth having a root-mean squared surface roughness of 0.3 nm. Films are conductive at room temperature and appear to follow a variable-range-hopping conduction mechanism below that. Ferromagnetism is observed at room temperature and is dependent on Cr concentration. The combination of these characteristics makes V_1−x Cr _x O₂ a viable candidate material for next generation spintronic multilayer devices.     

Iterative adaptive spatial filtering for noise‐suppression in functional magnetic resonance imaging time‐series

We present an iterative scheme for adaptive smoothing of functional magnetic resonance images. We propose a novel similarity measure to estimate the weights of the smoothing filter based on the functional similarity of the voxels under the smoothing kernel with the voxel under consideration as well as their similarity with a reference time‐course representing the expected BOLD response. We demonstrate the performance of the proposed method by applying the method to preprocess both simulated and real fMRI data. The method improves the functional SNR of the data while preserving the shapes of the functionally active region and its performance is not compromised when structured noise is the dominant noise source. © 2011 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 21, 260‐270, 2011;     

Evaluation of Dynamic Channel and Power Assignment for Cognitive Networks

In this paper, we develop a unifying optimization formulation to describe the Dynamic Channel and Power Assignment (DCPA) problem and an evaluation method for comparing DCPA algorithms. DCPA refers to the allocation of transmit power and frequency channels to links in a cognitive network so as to maximize the total number of feasible links while minimizing the aggregate transmit power. We apply our evaluation method to five representative DPCA algorithms proposed in the literature. This comparison illustrates the tradeoffs between control modes (centralized versus distributed) and channel/power assignment techniques. We estimate the complexity of each algorithm. Through simulations, we evaluate the effectiveness of the algorithms in achieving feasible link allocations in the network, and their power efficiency. Our results indicate that, when few channels are available, the effectiveness of all algorithms is comparable and thus the one with smallest complexity should be selected. The Least Interfering Channel and Iterative Power Assignment algorithm does not require cross-link gain information, has the overall lowest run time, and achieves the highest feasibility ratio of all the distributed algorithms; however, this comes at a cost of higher average power per link.     

Adaptive Power Control Scheme for Mobile Wireless Sensor Networks

Wireless Personal Communications - One of the major factors that affects the performance of wireless sensor networks (WSN) is its limited battery capacity. Mobile wireless sensor networks (MWSN)...     

Effect of Au additions on the structure and properties of (Fe0.5Co0.5)71Nb4Si5B20 bulk metallic glass

The effect of addition of gold (Au) on the structure and mechanical properties of (Fe_0.5Co_0.5)₇₁Nb₄Si₅B₂₀ BMG alloy was studied. Addition of Au formed crystals in the BMG alloy. Gradual increase in the amount of Au added to the BMG alloy resulted in an increase in the amount of crystallinity and hardness of the alloy. Hardness values in excess of 1100 H_V were found in all the alloys with a maximum value of 1245 H_V. The thermal transition temperatures were also found to increase with an increasing amount of Au. Corner cracks were produced in the alloy with 1.5?at.-% Au content showing a low indentation fracture toughness value of 2.98?MPa-m^0.5.