Traffic grooming and clique partitioning‐based spectrum assignment in elastic optical networks

We adopt a fragmentation reducing policy for spectrum assignment and incorporate it with multicast traffic grooming in EON. To reduce fragmentation, the spectrum is partitioned based on the clique partitioning approach and spectral slots are assigned to traffic demands depending on which partition they belong. Simulation results predict that the proposed approach has better spectrum slot utilization compared to the state‐of‐the‐art non‐partitioning approach and the proposed approach reduces fragmentation, and also has less blocking ratio compared to the state‐of‐the‐art partitioning approach.     

Pseudo-Jahn–Teller effects in two-dimensional silicene,germanene and stanene: a crystal orbital vibronic coupling density analysis

The presence of the pseudo-Jahn–Teller (PJT) effect has been investigated in the heavier analogues of graphene, namely silicene, germanene and stanene, by applying the orbital vibronic coupling density theory. In order to do so, we have made a vis-a-vis analogy with their respective planar, honeycomb molecular cluster models, namely hexasilabenzene \((\hbox {Si}_{6}\hbox {H}_{6}\)), hexagermabenzene \((\hbox {Ge}_{6}\hbox {H}_{6}\)) and hexastannabenzene \((\hbox {Sn}_{6}\hbox {H}_{6})\). One-to-one mapping of the occupied crystal orbitals and unoccupied crystal orbitals in two-dimensional (2D) Si, Ge and Sn systems to the occupied molecular orbitals and unoccupied molecular orbitals of the corresponding molecular units are used to identify PJT-active bands and compute the crystal orbital vibronic coupling density (c-OVCD) and crystal orbital vibronic coupling constants (c-OVCCs). c-OVCD and c-OVCC show the local picture of the PJT coupling in these 2D systems. This article exemplifies the fruitfulness of deciphering the structural aspects in materials based on orbitals of their corresponding simple molecular units—a reductionist quantum chemical approach to materials.     

Fatigue crack propagation under in‐phase and out‐of‐phase biaxial loading

Fatigue damage characteristics of aluminium alloy under complex biaxial loads such as in‐phase and out‐of‐phase loading conditions and different biaxiality ratios have been investigated. The effects of microscale phenomena on macroscale crack growth were studied to develop an in‐depth understanding of crack nucleation and growth. Material characterization was conducted to study the microstructure variability. Scanning electron microscopy was used to identify the second phase particles, and energy dispersive X‐ray spectroscopy was performed to analyse their phases and elements. Extensive quasi‐static and fatigue tests were conducted on Al7075‐T651 cruciform specimens over a wide range of load ratios and phases. Detailed fractography analysis was conducted to understand the crack growth behaviour observed during the fatigue tests. Significant differences in crack initiation and propagation behaviour were observed when a phase difference was applied. Primarily, crack retardation and splitting were observed because of the constantly varying mode mixity caused by phase difference. The crack growth behaviour and fatigue lives under out‐of‐phase loading were compared with those under in‐phase loading to understand the effect of mixed‐mode fracture.     

On-Demand Local Modification of High-Tc Superconductivity in Few Unit-Cell Thick Bi2Sr2CaCu2O8+δ

High-temperature superconductors (HTSs) are important for potential applications and for understanding the origin of strong correlations. Bi₂Sr₂CaCu₂O_8+δ (BSCCO), a van der Waals material, offers a platform to probe the physics down to a unit-cell. Guiding the flow of electrons by patterning 2DEGS and oxide heterostructures has brought new functionality and access to new science. Similarly, modifying superconductivity in HTS locally, on a small length scale, is of immense interest for superconducting electronics. A route to modify superconductivity locally by depositing metal on the surface is reported here by transport studies on few unit-cell thick BSCCO. Deposition of chromium (Cr) on the surface over a selected area of BSCCO results in insulating behavior of the underlying region. Cr locally depletes oxygen in CuO₂ planes and disrupts the superconductivity in the layers below. This technique of modifying superconductivity is suitable for making sub-micrometer superconducting wires and more complex superconducting devices.     

Anti-CD40 ligand antibody treatment of SNF1 mice with established nephritis: preservation of kidney function

Prior studies have demonstrated that treatment of young, prenephritic lupus-prone mice with Ab directed against CD40 ligand (CD40L) prolongs survival and decreases the incidence of severe nephritis. In this report, we show that for (SWR x NZB)F1 (SNF1) animals with established lupus nephritis, long-term treatment with anti-CD40L beginning at either 5.5 or 7 mo of age prolonged survival and decreased the incidence of severe nephritis. "Older" mice were chosen for these studies to more closely resemble the clinical presentation of patients with established renal disease. We show that age at the start of treatment, which typically correlates with severity of disease, is an important factor when determining an efficacious therapeutic protocol since animals that began treatment at 7 mo of age required a more aggressive treatment protocol than animals at 5.5 mo of age. Remarkably, several anti-CD40L-treated animals beginning treatment at age 5.5 mo demonstrated a decline in proteinuria, as opposed to increasing proteinuria levels seen in hamster IgG (HIg)-treated controls, and histologic examination of kidneys from anti-CD40L-treated mice revealed dramatically diminished inflammation, sclerosis/fibrosis, and vasculitis, in marked contrast to the massive inflammation and kidney destruction observed in control animals that received hamster IgG. Spleens from anti-CD40L-treated mice also exhibited markedly reduced inflammation and fibrosis compared with controls. Together, these results show that treatment of older, nephritic SNF1 animals with long-term anti-CD40L immunotherapy significantly prolongs survival, reduces the severity of nephritis, and diminishes associated inflammation, vasculitis, and fibrosis.     

Can quantum discord increase in a quantum communication task?

Quantum teleportation of an unknown quantum state is one of the few communication tasks which has no classical counterpart. Usually the aim of teleportation is to send an unknown quantum state to a receiver. But is it possible in some way that the receiver’s state has more quantum discord than the sender’s state? We look at a scenario where Alice and Bob share a pure quantum state and Alice has an unknown quantum state. She performs joint measurement on her qubits and channel to prepare Bob’s qubits in a mixed state which has higher quantum discord than hers. We also observe an interesting feature in this scenario, when the quantum discord of Alice’s qubits increases, then the quantum discord of Bob’s prepared qubits decreases. Furthermore, we show that the fidelity of one-qubit quantum teleportation using Bob’s prepared qubits as the channel is higher than using Alice’s qubits.     

Rail-to-rail split-output SET tolerant digital gates

Analog Integrated Circuits and Signal Processing - Electronic circuits operating in the radiation intensive environment like space, are subject to a barrage of cosmic particles like neutrons,...     

Unsupervised band extraction for hyperspectral images using clustering and kernel principal component analysis

The ‘curse of dimensionality’ is a drawback for classification of hyperspectral images. Band extraction is a technique for reducing the dimensionality and makes it computationally less complex for classification. In this article, an unsupervised band extraction method for hyperspectral images has been proposed. In the proposed method, kernel principal component analysis (KPCA) is used for transformation of the original data, which integrates the nonlinear characteristics, as well as, the advantages of principal component analysis and extract higher order statistics of data. The KPCA is highly dependent on the number of patterns for calculating kernel matrix. So, a proper selection of subset of patterns, which represent the original data properly, may reduce the computational cost for the proposed method with considerably better performance. Here, density-based spatial clustering technique is first used to group the pixels according to their similarity, and then some percentages of pixels from each cluster are selected to form the proper subset of patterns. To demonstrate the effectiveness of the proposed clustering- and KPCA-based unsupervised band extraction method, investigation is carried out on three hyperspectral data sets, namely, Indian, KSC, and Botswana. Four evaluation measures, namely classification accuracy, kappa coefficient, class separability, and entropy are calculated over the extracted bands to measure the efficiency of the proposed method. The performance of the proposed method is compared with four state-of-the-art unsupervised band extraction approaches, both qualitatively and quantitatively, and shows promising results compared to them in terms of four evaluation measures.     

Effect of electron beam radiation on mechanical and electrical properties of poly(ethylene-co-vinyl acetate)

Ethylene-vinyl acetate (EVA) copolymer (12% vinyl acetate content) is subjected to electron beam irradiation using trimethylolpropane trimethacrylate (TMPTMA) as a radiation sensitizer. Mechanical and electrical studies of these irradiated samples show that the strength properties (tensile strength, elongation at break) are increased with radiation dosage up to an optimum radiation dose and sensitizer level above which the properties begin to deteriorate. Crosslinking of the polymer takes place on irradiation which is attributed to an increased gel content with increasing radiation dose. Compared to the original samples both dielectric constant and dielectric loss factor decrease for samples subjected to irradiation.     

Process development for electrocarboxylationof 2-acetyl-6-methoxynaphthalene

Electrochemical carboxylation of 2-acetyl-6-methoxynaphthalene to 2-hydroxy-2-(6-methoxy-2-naphthyl)propionic acid may be carried out in good yield (89% in the electrolysis; 75% as isolated dried product) in an undivided flow cell using lead as the cathode and aluminium as the dissolving anode. Dimethylformamide was found to be the best solvent for the reaction and low cost tetraethylammonium chloride hydrate is a good electrolyte for the system. The best conditions are those that increase carbon dioxide concentration although higher pressure seems to be more effective than low temperature. The reaction may be carried out with good yield at fairly high current density (1150Am–1) and higher current densities are likely attainable. The allowable payload is limited to around 10% because higher payloads (20%) resulted in solution too viscous to pump. Initially it was surmised that trace quantities of water would be detrimental to good yields in these reactions. However, it was found that small amounts of water (that associated with typical quaternary ammonium chloride salts) has the beneficial effect of eliminating the major byproduct which is formed in more nearly anhydrous solutions without resulting in formation of alternative byproducts. Process conditions were evaluated at 0.2L scale, then scaled up to 1L and finally 75L. The best results were attained in the 1L system, solvable operating problems limited the yield in the largest scale electrolysis.