119 research outputs found

    Stochastic Consensus-based Control of μGs with Communication Delays and Noises

    Get PDF

    Developmental periods of Oenopia conglobata contaminata (Col.: Coccinellidae) reared on eggs of Sitotroga cerealella (Lep.: Gelechiidae) and Ephestia kuehniella (Lep.: Pyralidae) at constant temperatures

    Get PDF
    The coccinellid Oenopia conglobata contaminata (Menteries) is one of the most important predators of orchard pests in Iran. The effect of eggs of Sitotroga cereallela Olivier (Lep.: Gelechiidae) and Ephestia kuehniella Zeller (Lep.: Pyralidae) on development and survival of this beetle was studied and compared under laboratory conditions (five constant temperatures i.e., 22.5 ± 1, 25 ± 1, 27.5 ± 1, 30 ± 1 and 32.5 ± 1 °C 55 ± 5% relative humidity (R. H.) and a 16:8 h light: dark photoperiod). Total developmental time at the above-mentioned temperatures were 28.83 ± 0.17, 24.52 ± 0.37, 21,39 ± 0.21 17.92 ± 0.16 and 18.22 ± 0.29 days on S. cereallelaand27 ± 0.38, 23.32 ± 0.14, 19.57 ± 0.28, 16.14 ± 0.17 and 16.33 ± 0.05 days on E. kuehniella. The lower developmental thresholds (T0) of egg, larva, pupa and egg to adult on E. kuehniella were estimated15.02, 8.6, 7.48 and 8.55 ºC and the thermal constant for these periods calculated as 38.16, 222.22, 71.9 and 370.37 DD. The lower developmental thresholds on S. cereallela were found to be 13.79, 5.6, 5.82 and 6.54 ºC andthermal constant for the mentioned periods were 41.15, 277.77, 91.7, 454.54 DD, respectively. Although significant differences between developmental times at different temperatures exist, no significant differences was observed between 30 and 32.5 °C for two prey species. The results suggest that E. kuehniella serves as a more effective host than S. cereallela for rearing of coccinellid O. conglobata

    Quantum discord evolution of three-qubit states under noisy channels

    Full text link
    We investigated the dissipative dynamics of quantum discord for correlated qubits under Markovian environments. The basic idea in the present scheme is that quantum discord is more general, and possibly more robust and fundamental, than entanglement. We provide three initially correlated qubits in pure Greenberger-Horne-Zeilinger (GHZ) or W state and analyse the time evolution of the quantum discord under various dissipative channels such as: Pauli channels σx\sigma_{x}, σy\sigma_{y}, and σz\sigma_{z}, as well as depolarising channels. Surprisingly, we find that under the action of Pauli channel σx\sigma_{x}, the quantum discord of GHZ state is not affected by decoherence. For the remaining dissipative channels, the W state is more robust than the GHZ state against decoherence. Moreover, we compare the dynamics of entanglement with that of the quantum discord under the conditions in which disentanglement occurs and show that quantum discord is more robust than entanglement except for phase flip coupling of the three qubits system to the environment.Comment: 17 pages, 4 figures, accepted for publication in EPJ

    Dr. Inventor, Promoting Scientific Creativity by Utilising Web-based Research Objects, FP7

    Get PDF
    Scientific creativity and innovation represent the beating heart of European growth at a time of rapid technological change. Dr Inventor is built on the vision that technologies have great potential to supplement human ingenuity in science by overcoming the limitations that people suffer in pursuing scientific discovery. It presents an original system that will provide inspiration for scientific creativity by utilising the rich presence of web-based research resources. Dr Inventor will act as a personal research assistant, utilising machine-empowered search and computation to bring researchers extended perspectives for scientific innovation by informing them of a broad spectrum of relevant research concepts and approaches, by assessing the novelty of research ideas, and by offering suggestions of new concepts and workflows with unexpected features for new scientific discovery. Dr Inventor is an attempt to understand the potential of technology in the scientific creative process within current technology limitations. It represents a sound balance between scientific insight into individual scientific creative processes and technical implementation using innovative technologies in information extraction, document summarization, semantics and visual analytics. The outcomes will be integrated into a web-based system that will allow evaluation in a selected research area under real-world settings with carefully designed metrics, benchmarks and baseline for creative performance, leading to tangible measurements on the performance of the technologies in enhancing human creativity and a blueprint for future technologies in computational creativity. Dr Inventor has huge implications for scientific innovation in Europe, as it has the potential to change the way in which scientific research is undertaken. The acceptance of the system by general research communities will open opportunities for many industrial sectors, leading to reinforced leadership of European industry

    Dynamics of multipartite quantum correlations under decoherence

    Full text link
    Quantum discord is an optimal resource for the quantification of classical and non-classical correlations as compared to other related measures. Geometric measure of quantum discord is another measure of quantum correlations. Recently, the geometric quantum discord for multipartite states has been introduced by Jianwei Xu [arxiv:quant/ph.1205.0330]. Motivated from the recent study [Ann. Phys. 327 (2012) 851] for the bipartite systems, I have investigated global quantum discord (QD) and geometric quantum discord (GQD) under the influence of external environments for different multipartite states. Werner-GHZ type three-qubit and six-qubit states are considered in inertial and non-inertial settings. The dynamics of QD and GQD is investigated under amplitude damping, phase damping, depolarizing and flipping channels. It is seen that the quantum discord vanishes for p>0.75 in case of three-qubit GHZ states and for p>0.5 for six qubit GHZ states. This implies that multipartite states are more fragile to decoherence for higher values of N. Surprisingly, a rapid sudden death of discord occurs in case of phase flip channel. However, for bit flip channel, no sudden death happens for the six-qubit states. On the other hand, depolarizing channel heavily influences the QD and GQD as compared to the amplitude damping channel. It means that the depolarizing channel has the most destructive influence on the discords for multipartite states. From the perspective of accelerated observers, it is seen that effect of environment on QD and GQD is much stronger than that of the acceleration of non-inertial frames. The degradation of QD and GQD happens due to Unruh effect. Furthermore, QD exhibits more robustness than GQD when the multipartite systems are exposed to environment.Comment: 15 pages, 4 figures, 4 table

    Detecting Manipulations in Video

    Get PDF
    This chapter presents the techniques researched and developed within InVID for the forensic analysis of videos, and the detection and localization of forgeries within User-Generated Videos (UGVs). Following an overview of state-of-the-art video tampering detection techniques, we observed that the bulk of current research is mainly dedicated to frame-based tampering analysis or encoding-based inconsistency characterization. We built upon this existing research, by designing forensics filters aimed to highlight any traces left behind by video tampering, with a focus on identifying disruptions in the temporal aspects of a video. As for many other data analysis domains, deep neural networks show very promising results in tampering detection as well. Thus, following the development of a number of analysis filters aimed to help human users in highlighting inconsistencies in video content, we proceeded to develop a deep learning approach aimed to analyze the outputs of these forensics filters and automatically detect tampered videos. In this chapter, we present our survey of the state of the art with respect to its relevance to the goals of InVID, the forensics filters we developed and their potential role in localizing video forgeries, as well as our deep learning approach for automatic tampering detection. We present experimental results on benchmark and real-world data, and analyze the results. We observe that the proposed method yields promising results compared to the state of the art, especially with respect to the algorithm’s ability to generalize to unknown data taken from the real world. We conclude with the research directions that our work in InVID has opened for the future

    Correlation dynamics of three spin under a classical dephasing environment

    Full text link
    By starting from the stochastic Hamiltonian of the three correlated spins and modeling their frequency fluctuations as caused by dephasing noisy environments described by Ornstein-Uhlenbeck processes, we study the dynamics of quantum correlations, including entanglement and quantum discord. We prepared initially our open system with Greenberger-Horne-Zeilinger or W state and present the exact solutions for evolution dynamics of entanglement and quantum discord between three spins under both Markovian and non-Markovian regime of this classical noise. By comparison the dynamics of entanglement with that of quantum discord we find that entanglement can be more robust than quantum discord against this noise. It is shown that by considering non-Markovian extensions the survival time of correlations prolong.Comment: 13 pages, 4 figure

    Approximation Algorithms for 2-Stage Stochastic Optimization Problems

    Full text link
    Abstract. Stochastic optimization is a leading approach to model optimization problems in which there is uncertainty in the input data, whether from measurement noise or an inability to know the future. In this survey, we outline some recent progress in the design of polynomialtime algorithms with performance guarantees on the quality of the solutions found for an important class of stochastic programming problems — 2-stage problems with recourse. In particular, we show that for a number of concrete problems, algorithmic approaches that have been applied for their deterministic analogues are also effective in this more challenging domain. More specifically, this work highlights the role of tools from linear programming, rounding techniques, primal-dual algorithms, and the role of randomization more generally.
    • …
    corecore