Detection of Review Abuse via Semi-Supervised Binary Multi-Target Tensor Decomposition

Product reviews and ratings on e-commerce websites provide customers with detailed insights about various aspects of the product such as quality, usefulness, etc. Since they influence customers' buying decisions, product reviews have become a fertile ground for abuse by sellers (colluding with reviewers) to promote their own products or to tarnish the reputation of competitor's products. In this paper, our focus is on detecting such abusive entities (both sellers and reviewers) by applying tensor decomposition on the product reviews data. While tensor decomposition is mostly unsupervised, we formulate our problem as a semi-supervised binary multi-target tensor decomposition, to take advantage of currently known abusive entities. We empirically show that our multi-target semi-supervised model achieves higher precision and recall in detecting abusive entities as compared to unsupervised techniques. Finally, we show that our proposed stochastic partial natural gradient inference for our model empirically achieves faster convergence than stochastic gradient and Online-EM with sufficient statistics.Comment: Accepted to the 25th ACM SIGKDD Conference on Knowledge Discovery and Data Mining, 2019. Contains supplementary material. arXiv admin note: text overlap with arXiv:1804.0383

Lepton number violation via intermediate black hole processes

Black holes at the TeV scale are investigated in the extra large dimension scenario. We interpret the lightest black hole excitation as a singlet scalar field, and show how interaction terms can be appended to the standard model at the dimension five non-renormalizable level. Lepton family number violation is natural in this model. Muon magnetic moment, and neutrino masses are investigated. We also present a quantization scheme in n dimensions.Comment: 5 pages, 4 figure

Electro-Reflectance Spectra of Blue Bronze

We show that the infrared reflectance of the quasi-one dimensional charge-density-wave (CDW) conductor K0.3MoO3 (blue bronze) varies with position when a voltage greater than the CDW depinning threshold is applied. The spatial dependence and spectra associated with these changes are generally as expected from the electro-transmission [B.M. Emerling, et al, Eur. Phys. J. B 16, 295 (2000)], but there are some differences which might be associated with changes in the CDW properties on the surface. We have examined the electro-reflectance spectrum associated with CDW current investigation for light polarized parallel to the conducting chains for signs of expected current-induced intragap states, and conclude that the density of any such states is at least an order of magnitude lower than expected.Comment: 1)submitted to Eur. Phys. J B 2) revised (July 24) to a) better emphasize results and b) with new figure insets to make paper more self-containe

Masses and decay modes of charmonia using a confinement model

The masses of charmonium s and p-states, pseudoscalar and vector decay constants, leptonic, hadronic as well as radiative decay widths for charmonia have been computed in the framework of extended harmonic confinement model without any additional parameters. The outcome in comparison with other contemporary theoretical and experimental results is presented.Comment: Submitted to AIP for proceedings of International Workshop on Theoretical High Energy Physics held at IIT Roorkee, INDIA during 15-20 March, 200

Three Dimensional Nanowire Array Piezo-phototronic and Piezo-photo-magnetotronic Sensors

Piezotronic and piezo-phototronic is a burgeoning field of study which emerges from the coupling of intrinsic materials properties exhibited by non-centrosymmetric semiconductors. In the past decade research efforts were mainly focused on the wurtzite family of 1D nanostructures, with major emphasis on ZnO nanowire nanogenerators, MS piezotronic transistors, LEDs and photodetectors mainly integrated on single nanowires. In view of previously known advantages of charge carrier separation in radial heterojunctions, particularly in type-II core/shell nanowires, it can be anticipated that the performance of photosensing devices can be largely enhanced by piezo-phototronic effect. Moreover, the performance metrics can be further improved in an array of nanowires where geometrical feature enabled multiple reflection can efficiently trap incident illumination. The crux of this dissertation lies in the development of 3D type-II core/shell nanowire array based piezo-phototronic device and also to investigate the effect of magnetic field on ZnO nanowire arrays based piezotronic and piezo-phototronic device for new class of sensors. In this regard, prototype piezo-phototronic broadband photodetectors integrated on two material systems, namely type-II CdSe/ZnTe 3D core/shell nanowire arrays and fully wide band gap type-II ZnO/ZnS 3D core/shell nanowire arrays have been developed where the photodetection performance of each device exhibits high sensitivity, fast response and large responsivity. The application of piezo-phototronic effect further improves the device performance by three to four orders of magnitude change numerically calculated from absolute responsivities at multiple wavelengths. A 3D ZnO nanowire array based new class of piezo-photo-magnetotronic sensor is also developed for detection of pressure, illumination and magnetic field suggesting multiple functionality of a single device where more than one effect can be coupled together to exhibit piezo-magnetotronic or piezo-photo-magnetotronic type of device behavior

Cyclic variations in the ovarian activity of a fresh water perch Colisa fasciatus (Bl. & Schn.)

A morfologia geral, histologia e mudanças cíclicas no ovário de Colisa fasciatus foram descritas. 0 ovário apresenta um tipo assincrônico de desenvolvimento ovocitário, com um só pico de desova que se estende de junho a agosto. 0 ooplasma, núcleo e constituintes da parede celular exibem distintas mudanças morfológicas e histológicas durante seu ciclo anual. 0 aparecimento de núcleos de vitelo, extrusões nucleolares e deposição de vitelo foram discutidas

A Critical Review of the Principles Governing Diet Intake in Ayurveda

Diet has been given very crucial importance in Ayurveda regarding maintenance of health and causation of diseases. A lot of description about what to eat and how to eat has been given in the texts. This article discusses the rules for deciding the food for an individual and eating the food as given in Ayurveda in the light of scientific knowledge