On the Topological Origin of Entanglement in Ising Spin Glasses

The origin of thermal and quantum entanglement in a class of three-dimensional spin models, at low momenta, is traced to purely topological reasons. The establishment of the result is facilitated by the gauge principle which, when used in conjunction with the duality mapping of the spin models, enables us to recast them as lattice Chern-Simons gauge theories. The thermal and quantum entanglement measures are expressed in terms of the expectation values of Wilson lines, loops, and their generalisations. For continuous spins, these are known to yield the topological invariants of knots and links. For Ising-like models, they are expressible in terms of the topological invariants of three-manifolds obtained from finite group cohomology -- the so-called Dijkgraaf-Witten invariants.Comment: RevTex4, 6 page

Possible ferro-spin nematic order in NiGa2S4

We explore the possibility that the spin-1 triangular lattice magnet NiGa2 S4 may have a ferro-nematic ground state with no frozen magnetic moment but a uniform quadrupole moment. Such a state may be stabilized by biquadratic spin interactions. We describe the physical properties of this state and suggest experiments to help verify this proposal. We also contrast this state with a `non-collinear' nematic state proposed earlier by Tsunetsugu and Arikawa for NiGa2S4

Emergence of Artificial Photons in an Optical Lattice

We establish the theoretical feasibility of direct analog simulation of the compact U(1) lattice gauge theories in optical lattices with dipolar bosons. We discuss the realizability of the topological Coulomb phase in extended Bose-Hubbard models in several optical lattice geometries. We predict the testable signatures of this emergent phase in noise correlation measurements, thus suggesting the possible emergence of artificial light in optical lattices.Comment: 4 pages, 2 eps figur

Algebraic spin liquid as the mother of many competing orders

We study the properties of a class of two-dimensional interacting critical states -- dubbed algebraic spin liquids -- that can arise in two-dimensional quantum magnets. A particular example that we focus on is the staggered flux spin liquid, which plays a key role in some theories of underdoped cuprate superconductors. We show that the low-energy theory of such states has much higher symmetry than the underlying microscopic spin system. This symmetry has remarkable consequences, leading in particular to the unification of a number of seemingly unrelated competing orders. The correlations of these orders -- including, in the staggered flux state, the Neel vector and the order parameter for the columnar and box valence-bond solid states -- all exhibit the SAME slow power-law decay. Implications for experiments in the pseudogap regime of the cuprates and for numerical calculations on model systems are discussed.Comment: Minor changes; final published version. 17 pages, 3 figure

Early congestion detection and adaptive routing in MANET

AbstractAd hoc mobile networks are composed of mobile nodes communicating through wireless medium, without any fixed backbone infrastructure. In these networks, congestion occurs in any intermediate node when data packets travel from source to destination and they incur high packet loss and long delay, which cause the performance degradations of a network. This paper proposes an early congestion detection and adaptive routing in MANET called as EDAPR. Initially EDAPR constructs a NHN (non-congested neighbors) neighbors list and finds a route to a destination through an NHN node. All the primary path nodes periodically calculate its queue_status at node level. While using early congestion detection technique, node detects congestion that is likely to happen and sends warning message to NHN nodes. The ancestor NHN node is aware of this situation and finds an alternate path to a destination immediately by applying adaptive path mechanism. Thus, EDAPR improves performance in terms of reducing delay, routing overhead and increases packet delivery ratio without incurring any significant additional cost. The performance of EDAPR was compared with EDAODV and EDCSCAODV using the Ns-2 simulator. The result reveals significant improvement over EDAODV and EDCSCAODV routing schemes

Light trap, an effective component of integrated management of Tuta absoluta(Lepidoptera : Gelechiidae) on Tomato

The effectiveness of mass trapping the moths of Tuta absoluta was evaluated using light traps in tomato polyhouse at ICAR-Indian Institute of Horticultural Research, Bengaluru during March - June, 2018. Various colours of light sources were evaluated for their efficacy in attracting the moths. Of different coloured light sources evaluated, yellow and white (bluish) were found relatively effective for attraction of the moths. The efficacy of mass trapping was further evaluated and incandescent yellow bulb of 60 W was found most efficient in attracting both sexes of Tuta moths. Thus light traps can be an effective tool for IPM of this pest on tomato, under polyhouse conditions

Control strategies for seamless transfer between the grid-connected and islanded modes of a microgrid system

Design of control strategies for Distributed generation systems is very important to achieve smoother transition between the grid connected and islanding modes of operation. The transition between these two modes of operation should be seamless, without any severe transients during the changeover. In this paper, two different control strategies namely inverter output current control and indirect grid current control for the seamless transfer between the modes of operation has been explored for the suitability. The design and analysis of the cascaded control loops based on Proportional Integral (PI) controller has been dealt in detail for both inverter output current control and indirect grid current control strategy. Control parameters are designed using the control system toolbox in MATLAB. A 10kW grid connected microgrid system has been designed and simulated in MATLAB/Simulink and the results are presented under grid connected operation, islanding operation and the transition between the modes considering fault condition in the grid side. The simulation studies are carried out using both the control strategies and the results are presented to validate the design methodology

Online access to DRDO periodicals using open source software

Defence Scientific Information and Documentation Centre (DESIDOC) is a nodal centre for information communication and dissemination in the Defence Research & Development Organization (DRDO). As the publication wing of DRDO, DESIDOC brings out regular publications including Defence Science Journal, DESIDOC Bulletin of Information Technology, DRDO Newsletter, DRDO Samachar and Technology Focus. These periodicals cover a wide variety of topics in various subject areas targeting different user communities situated all over India. A pilot project was undertaken with an aim to provide online desktop access to the full text of these periodicals to the users including R&D scientists of more than 50 laboratories and establishments. The project also aimed at facilitating the Publications Division to directly upload the contents to the system. The open source software EPrints is used and customized according to the user requirements particularly on Intranet. Upon successful testing and evaluation, these periodicals will be hosted on Internet allowing subscription, access and downloading by users across the globe. This paper discusses the experience in using EPrints and customization at various levels for DRDO publications and explains various features of the model

Mechanical Characterization of Coir Fiber and Cotton Fiber Reinforced Unsaturated Polyester Composites for Packaging Applications

The aim of this work is to develop a natural fiber composites that can become a substitute for plywood and medium density fiber boards used in packaging application. In this work, the composite was fabricated with randomly oriented chopped coir and cotton fiber reinforced with unsaturated polyester resin. The different types of composite materials were prepared with different quantity of coir fiber and cotton fiber reinforced with unsaturated polyester by using hand lay-up technique. Mechanical properties such as tensile, flexural, impact and hardness strength are evaluated. Scanning Electron Microscope (SEM) was conducted on the fabricated composite to analysis the interfacial properties, internal cracks and internal structure of the fractured surfaces. Based on the results, cotton fiber reinforced with unsaturated polyester has better mechanical properties to be used for packaging applications compared with other combinations of coir/cotton fiber reinforced with unsaturated polyester

FLAVONOID CONTENT AND ANTIBACTERIAL ACTIVITY OF ALBIZIA JULIBRISSIN. DURAZZ LEAF, STEM AND FLOWER EXTRACTS AGAINST CLINICALLY ISOLATED BACTERIAL PATHOGENS

Objective: To test the antibacterial efficacy of leaf, stem, and flower extracts of Albizia julibrissin against bacterial pathogens. Methods: Extraction of active metabolites was carried out by using six different solvents, and total flavonoid content in each extract was determined by Aluminium chloride method. To determine the antibacterial activity of extracts, disc diffusion method and tube dilution method were carried out. Zone of inhibition and Minimum inhibitory Concentration (MIC) were calculated. Results: Methanolic extracts of leaf samples of A. julibrissin showed highest extractive value (5.14g/100g) and total flavonoid content (35.14mg/g). In overall leaf extracts of A. julibrissin showed maximum zone of inhibition towards P. vulgaris (10.1 mm*) and least susceptible microorganism is S. typhi (3.5 mm*). Stem and flower extracts inhibited bacterial growth only at higher concentrations (MIC, 160-215 and 65-180µg/ml respectively). Conclusion: Apart from the energy crop, based on the results and value-added compounds present in A. julibrissin, it may be considered as antibacterial agent in future