Effect of LaAlO3_3 Surface Topography on RF Current Distribution in Superconducting Microwave Devices

A laser scanning microscope with a thermal spot size of about 4 $\mu$m is used to measure a quantity proportional to the rf current density in an operating superconducting co-planar waveguide microwave resonator. The twinning of the LaAlO$_3$ substrate produces a meandering of the current at the edges due to irregularities in the wet etching of the YBa$_2$Cu$_3$O$_{7-\delta}$ film associated with substrate twin domain blocks, and a ($\sim$ 20%) enhancement of the rf photoresponse at these locations. These irregularities are candidates for enhanced nonlinear response from the device. The effects of substrate twinning and the resulting edge features on the superconducting film are discussed and analyzed.Comment: 13 pages, 4 figures, submitted to Applied Physics Letter

CP-ABE IN DECENTRALIZED DISRUPTION-TOLERANT MILITARY NETWORKS FOR SECURE RETRIEVAL OF DATA

In this rapidly growing world, communication involves transfer of confidential information across the globe within a short amount of time. This kind of technical communication involves network of communicating devices. These devices will be carrying the confidential data across the devices which may be far apart. In military environment, communication disruption can occur because of intermittent network connectivity. Solution found for these kinds of disruption is the Disruption Tolerant Network (DTN) technology. This technology allows the soldiers to reliably access the data by using the capacity of the external storage nodes. Most challenging issue found in this DTN technology is enforcement of authorization policies and update of policies for the retrieval of confidential data.  CP-ABE is one such cryptographic method which provides the solution to the access control issues. But there exists several problems with regard to key escrow, attribute revocation and coordination of attributes which are issued by different key authorities when applying CP-ABE in decentralized DTNs. In this paper, more secured method for the retrieval of confidential data using CP-ABE for decentralized DTNs is proposed where sets of attributes will be generated and managed by multiple authorities independently and addresses several existing proble

A continuous compositional-spread technique based on pulsed-laser deposition and applied to the growth of epitaxial films

A novel continuous-compositional spread technique based on the non-uniformity of the deposition rate typically observed in Pulsed Laser Deposition (PLD) is introduced. The approach uses the spatial variations in the deposition-rate naturally occurring in PLD; therefore, there is no need for the masks typically used in combinatorial techniques. Consequently, combinatorial materials synthesis can be carried out under optimized film growth conditions (e.g. at high temperature). Additionally, lifting the need for post-annealing renders this method applicable to heat-sensitive materials and substrates (e.g. films of transparent oxides on polymer substrates). Composition determination across the sample and mapping of physical properties onto the ternary phase diagram is achieved via a simple algorithm using the parameters that describe the deposition-rate profiles. Results are shown for the high-temperature growth of crystalline perovskites (including (Ba,Sr)TiO3 and the formation of a metastable alloy between SrRuO3 and SrSnO3) and the room-temperature growth of transparent conducting oxides.Comment: 6 pages, accepted for publication in Rev. Sci. Inst

Study on the Fecundity and Gonado somatic index of Rastrelliger kanagurta (Cuvier, 1817) of southern coast of Maharashtra, India

Investigation of fecundity and gonado somatic index (GSI) of Rastrelliger kanagurta were carried out from March 2011 to February 2012. Fecundity was determined at different length, weight and ovary ranges of different individual fishes. Study revealed that at 5% significant level significant average absolute fecundity was found to be 1,08,266 and relative fecundity ranged from 407 to 1499. The number of ova generally increased with increase in length and weight. However, variations in fecundity with respect to length and weight were also noticed. The gonado-somatic index (GSI) was calculated for each individual fish (592 numbers) and was averaged for each month. The average GSI values were plotted against each month to analysed monthly variations. GSI showed wide variations between sex and it was highest for both males and females during the month of April and September, showing occurrence of more ripe individuals. Analysis of regression showed that there were significant relationship between the fecundity with the fish length, body weight and ovary weight

Overcoming data scarcity of Twitter: using tweets as bootstrap with application to autism-related topic content analysis

Notwithstanding recent work which has demonstrated the potential of using Twitter messages for content-specific data mining and analysis, the depth of such analysis is inherently limited by the scarcity of data imposed by the 140 character tweet limit. In this paper we describe a novel approach for targeted knowledge exploration which uses tweet content analysis as a preliminary step. This step is used to bootstrap more sophisticated data collection from directly related but much richer content sources. In particular we demonstrate that valuable information can be collected by following URLs included in tweets. We automatically extract content from the corresponding web pages and treating each web page as a document linked to the original tweet show how a temporal topic model based on a hierarchical Dirichlet process can be used to track the evolution of a complex topic structure of a Twitter community. Using autism-related tweets we demonstrate that our method is capable of capturing a much more meaningful picture of information exchange than user-chosen hashtags.Comment: IEEE/ACM International Conference on Advances in Social Networks Analysis and Mining, 201

Recent advances in pulsed-laser deposition of complex-oxides

Pulsed-laser deposition (PLD) is one of the most promising techniques for the formation of complex-oxide heterostructures, superlattices, and well-controlled interfaces. The first part of this paper presents a review of several useful modifications of the process, including methods inspired by combinatorial approaches. We then discuss detailed growth kinetics results, which illustrate that 'true' layer-by-layer (LBL) growth can only be approached, but not fully met, even though many characterization techniques reveal interfaces with unexpected sharpness. Time-resolved surface x-ray diffraction measurements show that crystallization and the majority of interlayer mass transport occur on time scales that are comparable to those of the plume/substrate interaction, providing direct experimental evidence that a growth regime exists in which non-thermal processes dominate PLD. This understanding shows how kinetic growth manipulation can bring PLD closer to ideal LBL than any other growth method available today.Comment: 37 pages, 9 figures. Revie

Sustainable optimizing WMN performance through meta-heuristic TDMA link scheduling and routing

Wireless mesh networks (WMNs) have become a popular solution for expanding internet service and communication in both urban and rural areas. However, the performance of WMNs depends on generating optimized time-division multiple access (TDMA) schedules, which distribute time into a list of slots called superframes. This study proposes novel meta-heuristic algorithms to generate TDMA link schedules in WMNs using two different interference/constraint models: multi-transmit-receive (MTR) and full-duplex (FD). The objectives of this study are to optimize the TDMA frame for packet transmission, satisfy the constraints, and minimize the end-to-end delay. The significant contributions of this study are: (1) proposing effective and efficient heuristic solutions to solve the NP-complete problem of generating optimal TDMA link schedules in WMNs; (2) investigating the new FD interference model to improve the network capacity above the physical layer. To achieve these objectives and contributions, the study uses two popular meta-heuristics, the artificial bee colony (ABC) and/or genetic algorithm (GA), to solve the known NP-complete problems of joint scheduling, power control, and rate control. The results of this study show that the proposed algorithms can generate optimized TDMA link schedules for both MTR and FD models. The joint routing and scheduling approach further minimizes end-to-end delay while maintaining the schedule's minimum length and/or maximum capacity. The proposed solution outperforms the existing solutions in terms of the number of active links, end-to-end delay, and network capacity. The research aims to improve the efficiency and effectiveness of WMNs in most applications that require high throughput and fast response time

Pitfalls in single clone crispr-cas9 mutagenesis to fine-map regulatory intervals

The majority of genetic variants affecting complex traits map to regulatory regions of genes, and typically lie in credible intervals of 100 or more SNPs. Fine mapping of the causal variant(s) at a locus depends on assays that are able to discriminate the effects of polymorphisms or mutations on gene expression. Here, we evaluated a moderate-throughput CRISPR-Cas9 mutagenesis approach, based on replicated measurement of transcript abundance in single-cell clones, by deleting candidate regulatory SNPs, affecting four genes known to be affected by large-effect expression Quantitative Trait Loci (eQTL) in leukocytes, and using Fluidigm qRT-PCR to monitor gene expression in HL60 pro-myeloid human cells. We concluded that there were multiple constraints that rendered the approach generally infeasible for fine mapping. These included the non-targetability of many regulatory SNPs, clonal variability of single-cell derivatives, and expense. Power calculations based on the measured variance attributable to major sources of experimental error indicated that typical eQTL explaining 10% of the variation in expression of a gene would usually require at least eight biological replicates of each clone. Scanning across credible intervals with this approach is not recommended