Performance optimization in delay tolerant networks using backtracking algorithm for fully credits distribution to contrast selfish nodes

The Journal of Supercomputing - Delay Tolerant Network (DTN) can be characterized as a heterogeneous network of nodes in which nodes mobility is high and resources are limited to transmit messages....     

Effect of Oxidation Heat Treatments on the Mechanical Behavior of a Si-C-O-Fiber-Reinforced Magnesium Aluminosilicate

Oxidized magnesium aluminosilicate composites reinforced with Si-C-O (Nicalon) fiber have been found to retain their as-received flexural strength. The elastic moduli of the oxidized composites exhibited an increase for samples oxidized at 1000°C and a decrease at higher temperatures. Densification of the matrix may increase the elastic modulus of composites oxidized at 1000°C, whereas cracks in the matrix and at the fiber-matrix interfaces may be responsible for the low elastic moduli of composites oxidized at higher temperatures. The interfacial friction stresses were high at or near the edges and low in the interior of the oxidized samples. As a result, the oxidized composites failed by fiber fracture on the surface, followed by delamination and fiber pullout in the interior.     

Stereoscopic visualization of laparoscope image using depth information from 3D model

Laparoscopic surgery is indispensable from the current surgical procedures. It uses an endoscope system of camera and light source, and surgical instruments which pass through the small incisions on the abdomen of the patients undergoing laparoscopic surgery. Conventional laparoscope (endoscope) systems produce 2D colored video images which do not provide surgeons an actual depth perception of the scene. In this work, the problem was formulated as synthesizing a stereo image of the monocular (conventional) laparoscope image by incorporating into them the depth information from a 3D CT model. Various algorithms of the computer vision including the algorithms for the feature detection, matching and tracking in the video frames, and for the reconstruction of 3D shape from shading in the 2D laparoscope image were combined for making the system. The current method was applied to the laparoscope video at the rate of up to 5 frames per second to visualize its stereo video. A correlation was investigated between the depth maps calculated with our method with those from the shape from shading algorithm. The correlation coefficients between the depth maps were within the range of 0.70–0.95 (P < 0.05). A t-test was used for the statistical analysis.     

Detection and elimination of mechanism defects in the selective precision synthesis of planar mechanisms

Possible mechanism defects and errors that may be encountered during the selective precision synthesis of planar mechanisms are discussed in detail and suitable remedial measures recommended. These defects include dyadic assembly error, locking defect, branching defect and the sequential mismatch defect. By solving these problems, the selective precision synthesis method can easily be adapted to solving numerous planar kinematic synthesis problems.     

Thermal cycle test of urea for latent heat storage applications

Accelerated thermal cycle tests for melt/freeze cycles of urea were conducted. Urea has shown a very high degradation in its latent heat and melting point within the first few cycles and did not melt after a few cycles. It is recommended that urea should not be used as a latent heat storage material. Copyright © 2001 John Wiley & Sons, Ltd.     

Highly efficient in-line wet cyclone air sampler for airborne virus detection

Journal of Mechanical Science and Technology - Early detection of highly pathogenic strains is particularly important from the point of view of controlling and minimizing the spread of the virus....     

Study of infrared spectroscopy and elastic properties of fine and coarse grained nickel–cadmium ferrites

The elastic properties of Cd _x Ni_1−x Fe₂O₄ (x = 0.2, 0.4, 0.6 and 0.8) spinel ferrite system synthesized by wet-chemical technique, have been studied by infra-red spectroscopy and X-ray diffraction pattern analysis before (W) and after high temperature annealing (AW). The average particle size for wet-samples was within the range 4–5 nm, which is much lower than the average particle size found for AW samples (≈85 nm). The force constants for tetrahedral and octahedral sites determined by infrared spectral analysis, lattice constant and X-ray density values by X-ray diffraction pattern analysis; have been used to calculate elastic constants. The elastic moduli for W-samples are found to be larger as compared to AW samples, which are explained on the basis of grain size reduction effect. The average crystallite size calculated from elastic data is in agreement to that determined from X-ray diffraction data analysis.     

Buffer-aided cooperative NOMA with partial relay selection

Telecommunication Systems - The Cooperative Non-orthogonal multiple access (C-NOMA) technique has been considered as a promising solution to improve the coverage extension and transmission...     

A Chain‐Elongated Oligophenylenevinylene Electrolyte Increases Microbial Membrane Stability

A novel conjugated oligoelectrolyte (COE) material, named S6 , is designed to have a lipid‐bilayer stabilizing topology afforded by an extended oligophenylenevinylene backbone. S6 intercalates biological membranes acting as a hydrophobic support for glycerophospholipid acyl chains. Indeed, Escherichia coli treated with S6 exhibits a twofold improvement in butanol tolerance, a relevant feature to achieve within the general context of modifying microorganisms used in biofuel production. Filamentous growth, a morphological stress response to butanol toxicity in E. coli, is observed in untreated cells after incubation with 0.9% butanol (v/v), but is mitigated by S6 treatment. Real‐time fluorescence imaging using giant unilamellar vesicles reveals the extent to which S6 counters membrane instability. Moreover, S6 also reduces butanol‐induced lipopolysaccharide release from the outer membrane to further maintain cell integrity. These findings highlight a deliberate effort in the molecular design of a chain‐elongated COE to stabilize microbial membranes against environmental challenges.