A fuzzy decision scheme for relay selection in cooperative wireless sensor network

In energy‐constrained military wireless sensor networks, minimizing the bit error rate (BER) with little compromise on network lifetime is one of the most challenging issues. This paper presents a new relay selection based on fuzzy logic (RSFL) scheme which provides balance between these parameters. The proposed scheme considers node's residual energy and path loss of the relay‐destination link as the input parameters for the selection of the relay node. The relay node selection by fuzzy logic is based on prioritizing higher residual energy and minimum path loss. To evaluate the performance on wireless sensor network, we compare the proposed scheme with the three existing relay selection strategies, ie, random, maximum residual energy based relay selection (MaxRes), and minimum energy consumption based relay selection (MinEnCon). The simulation results of the proposed scheme in terms of network lifetime, BER, Network Survivability Index (NSI), and average energy of network nodes have been presented and compared with different relay selection schemes. The simulation results show that the proposed RSFL scheme has the lowest BER, moderate network lifetime, average energy, and NSI.     

The modeling and analysis of a butting assembly in the presence of workpiece surface roughness and part dimensional error

Butt joints are frequently used in assembly processes. However, relatively little attention has been paid to the proper design and selection of butt joint geometries and processes. In this paper, the assembly accuracy performance of different butt joint geometries and joining processes has been studied by using analytical models for part misalignment in the presence of part dimensional errors, surface roughness, and surface waviness. Our analysis shows that both short-term roughness, as well as long-term waviness, has an effect on the assembly precision levels. The analysis is verified statistically using a simulation program; experiments are conducted using this program to show that the differences in the performance between different butt joining methods can be significant. Therefore, proper design and selection of forming butting assemblies can have important impacts on the assembly precision.     

Ethylene-propylene diene monomer-based polymer composite for attenuation of high energy radiations

Radiation shielding composites of ethylene-propylene diene monomer (EPDM), reinforced with tungsten (W) and barium sulphate (BaSO₄) in different filler weight (wt%) were synthesized. The effects of W and BaSO₄ on gamma and neutron attenuation properties of the composites were studied by experimental methods using ¹³⁷Cs, ⁶⁰Co and ²⁵²Cf radioactive sources. EPDM composites with W and BaSO₄ fillers were also investigated for filler dispersion using scanning electron microscopy and X-ray radiograph. The experimental results revealed that the incorporation of W and BaSO₄ significantly improved the radiation attenuation properties of the EPDM composites. It was observed that the attenuation properties of the composite material increases with higher concentration of the filler. The half-value layer (HVL), tenth value layer thickness and relaxation length of the composites were found to decrease with increasing concentration of the filler. The results also showed that the attenuation behaviour of 50 wt% BaSO₄ filled polymer composite is comparable to that of the composite with 25 wt% W. The developed composite with 75 wt% W filler exhibited the maximum radiation attenuation with lowest HVL thicknesses.     

LF-SegNet: A Fully Convolutional Encoder–Decoder Network for Segmenting Lung Fields from Chest Radiographs

Wireless Personal Communications - Segmentation of lung fields is an important pre-requisite step in chest radiographic computer-aided diagnosis systems as it precisely defines the...     

Experimental and mathematical analysis of simulation results for sheet metal parts in deep drawing

In this paper, deep drawing of conical and cylindrical cups without blank holder is investigated using a conical die design. These cups are produced by pushing circular blanks by pushing the flat head punch in a single stroke. ANSYS APDL 14.0 was then used to investigate the effects of die and punch geometry, half-cone angle, die and punch fillet radius, and drawing load. The thickness distribution of the cup was numerically investigated to determine the optimal process design, and mathematical analysis was adopted to determine the thickness distribution and longitudinal stress calculation. An experimental set-up was designed to validate the simulation results for conical and cylindrical shaped sheet-metal cups. Tensile tests were carried out to obtain the flow of the stress-strain curve for the simulation. The drawing characteristics of materials were investigated by performing Erichsen cupping and Vickers hardness tests. Experiments were conducted on blanks of aluminum alloys and stainless steel with initial thicknesses of 1.5 mm. A cylindrical cup of ss304 with LDR of up to 2.2 and conical cup of AA1100 with LDR of up to 2.7 were successfully achieved. Finite element simulation results showed good agreement with the mathematical and experimental results.     

Ferroic ordering and charge‐spin‐lattice order coupling in Gd‐doped Fe3O4 nanoparticles relaxor multiferroic system

We investigated the effect of gadolinium doping (1‐5 at.%) on the magnetic and dielectric properties of Fe₃O₄ nanoparticles, synthesized by the chemical co‐precipitation technique, primarily to understand the onset of multifunctional properties such as ferroelectricity and magnetodielectric coupling. The substitution of larger Gd³⁺ ions at smaller Fe³⁺ octahedral sites in inverse spinel Fe₃O₄ has significantly influenced the morphology, average crystallite size, and more importantly, the magneto‐crystalline anisotropy and saturation magnetization. The magneto‐crystalline anisotropy and the saturation magnetization decreases substantially, however, significant increase in the average crystallite size is observed upon Gd doping. Furthermore, temperature‐dependent dielectric studies suggest that these nanoparticle systems exhibit relaxor ferroelectric behavior, with much pronounced ferroelectric polarization moment recorded for 5 at.% Gd doped Fe₃O₄ as compared to its undoped counterpart.     

Analysis of a nonisothermal simulated moving‐bed reactor

Simulated moving‐bed reactor (SMBR) is a multifunctional reactor wherein in situ separation of the products facilitates the reversible reaction to completion beyond thermodynamic equilibrium and at the same time obtaining products of high purity. In this work, we investigate the feasibility of introducing variances in adsorption strength, which has recently been proven to effectively improve SMB performance for pure separation, into an SMB system to include reactions. Synthesis of methyl acetate catalyzed by amberlyst 15 is considered as model system. Numerical simulations were carried out for an SMBR unit consisting of four columns and operated with various temperature distributions in the range of 308–323 K. SMBR productivities were evaluated and compared under the constraints of complete conversion and complete product separation. The effects of kinetics, heat transfer efficiency and adsorption strength of reactant were systematically investigated. © 2013 American Institute of Chemical Engineers AIChE J, 59: 4705–4714, 2013     

Structural and Mössbauer Investigation of Nanocrystalline SrFe1−xTixO3−δ

Crystal structure and cation distribution of nanocrystalline SrFe_1?xTi_xO_3?δ (0 ≤ x ≤ 0.3) synthesized by combined high‐energy ball milling and solid‐state reactions are investigated using Neutron powder diffraction and Mössbauer spectroscopy. Ti doping stabilizes the single phase tetragonal structure with I4/mmm space group up to x = 0.3. The neutron and Mössbauer data confirm that Fe exists in three different sites both crystallographically as well as magnetically in all the four compositions. The cation distribution at various sites is established through Rietveld refinement.     

A system for automatic animation of piano performances

Playing the piano requires one to precisely position one's hand in order to strike particular combinations of keys at specific moments in time. This paper presents the first system for automatically generating three‐dimensional animations of piano performance, given an input midi music file. A graph theory‐based motion planning method is used to decide which set of fingers should strike the piano keys for each chord. As the progression of the music is anticipated, the positions of unused fingers are calculated to make possible efficient fingering of future notes. Initial key poses of the hands, including those for complex piano techniques such as crossovers and arpeggio, are determined on the basis of the finger positions and piano theory. An optimization method is used to refine these poses, producing a natural and minimal energy pose sequence. Motion transitions between poses are generated using a combination of sampled piano playing motion and music features, allowing the system to support different playing styles. Our approach is validated through direct comparison with actual piano playing and simulation of a complete music piece requiring various playing skills. Extensions of our system are discussed. Copyright © 2012 John Wiley & Sons, Ltd.     

Interoperability Verification in ISO 18000-7 Active RFID Systems: Experimental Setup and Results

Interoperability in an RFID system conforming to ISO 18000-7 standard is defined as the ability of any commercial interrogator to communicate with any commercial tag. A possibility that conformance verification in the physical communication layer between active tags and interrogators (readers) does not satisfy the interoperability property is established. Challenging the traditional or matrix test to verify interoperability, a novel methodology to verify interoperability for active RFID systems in particular and all communication systems following a command-reply protocol in general is introduced in a prior publication. In this article, the methodology is experimentally implemented using industry standard laboratory equipment and automation tools to develop a fully automated interoperability test suite. The automated test system design considerations, challenges and results are discussed in detail. For a particular equipment, the NI-5671 Radio Frequency Signal generator, the maximum number of samples that can be tested for different parameters of the physical communication layers are provided. The equipment limitations are discussed to provide the reader with guidelines to experiment with, and a reference to evaluate the resolution (one measure of the accuracy of the test) of different equipment. The different parameters considered in the test and their interactions in determining the interoperability property are recorded.