587 research outputs found

    Effectiveness of specific rubber bearing isolator for multi-storeyed residential building in Dhaka

    Get PDF
    Earthquake is one of the most dreadful, sudden and uncontrolled natural disasters. „Base Isolation‟ is one of the popular seismic retrofitting techniques used through-out the world. The prime objective of this study is to identify the effectiveness of a specific rubber bearing isolator in reducing the overall drift of a structure caused by lateral forces like earthquake. An 8 storey RCC building assumed to be located in the moderate seismic zone of Bangladesh is taken as a reference for this work. The building is modelled with and without base „Isolator‟ by using the finite element software „SAP 2000‟ and designed by adopting the building design code „ACI 318‟. It is evident from the research that, use of the rubber bearing isolator increases the fundamental period of vibration and the overall displacement of the structure to a greater extent. At the same time the relative storey drift decreases significantly. Though the whole work focuses on a specific example, but it paves the way for the design of rubber bearing isolators which can be used in the multi-storeyed residential buildings with confidence

    Cloud-based online social network

    Get PDF
    International audienceOnline social media network has become part of human life by transforming the way users create new social relations or relate with family and friends. Online social network (OSN) has drastically increased the rate at which people interact with each other by simplifying the means of communication. However, privacy is raising a serious concern. All user generated data within the OSN system need to be protected against unauthorized friends or hackers or even against the provider of OSN. Many research works are going on to encounter the privacy issues in OSN. This paper analyses the limitations of the recent work being done in this field and proposes an efficient abstract solution to them

    Genetic diversity of kampung chicken (Gallus gallus domesticus) from selected areas in East Coast Peninsular Malaysia inferred from partial control region of mitochondrial DNA

    Get PDF
    After the 2014 Malaysia massive flood, genetic variation of the kampung chicken Gallus gallus domesticus in East Coast Peninsular Malaysia (ECPM) was investigated for a better understanding of their genetic diversity for its conservation. A total of fifty-nine samples were collected from three states; Kelantan, Terengganu and Pahang for mitochondrial DNA analysis. Partial mtDNA control regions were amplified, sequenced, and analyzed to determine the genetic variation among the states. Eleven haplotypes were detected among all the samples. Hap-1 was the most widespread haplotype among the three states and comprised of 45.8% of all samples. Genetic variation was the highest in Pahang (Pi = 0.01037, Hd = 0.8676), followed by Terengganu (Pi = 0.00938, Hd = 0.7316) and Kelantan (Pi = 0.00363, Hd = 0.5579). Low nucleotide diversity in Kelantan indicated the loss of genetic resources, which might be due to the population bottleneck phenomenon. Both the non-significant values of Tajima’s D and Fu’s FS in Pahang and Terengganu, suggested that they were at genetic equilibrium. Significant deviation from Tajima’s D neutrality test (P<0.05) in Kelantan indicated the possibility of population expansion, which might be a result of population recovery from the population bottleneck due to the massive flood in December 2014

    Pulse Shape Discrimination in the IGEX Experiment

    Get PDF
    The IGEX experiment has been operating enriched germanium detectors in the Canfranc Underground Laboratory (Spain) in a search for the neutrinoless double decay of 76Ge. The implementation of Pulse Shape Discrimination techniques to reduce the radioactive background is described in detail. This analysis has been applied to a fraction of the IGEX data, leading to a rejection of ~60 % of their background, in the region of interest (from 2 to 2.5 MeV), down to ~0.09 c/(keV kg y).Comment: 18 pages, 10 figure

    Measurement of double beta decay of 100Mo to excited states in the NEMO 3 experiment

    Full text link
    The double beta decay of 100Mo to the 0^+_1 and 2^+_1 excited states of 100Ru is studied using the NEMO 3 data. After the analysis of 8024 h of data the half-life for the two-neutrino double beta decay of 100Mo to the excited 0^+_1 state is measured to be T^(2nu)_1/2 = [5.7^{+1.3}_{-0.9}(stat)+/-0.8(syst)]x 10^20 y. The signal-to-background ratio is equal to 3. Information about energy and angular distributions of emitted electrons is also obtained. No evidence for neutrinoless double beta decay to the excited 0^+_1 state has been found. The corresponding half-life limit is T^(0nu)_1/2(0^+ --> 0^+_1) > 8.9 x 10^22 y (at 90% C.L.). The search for the double beta decay to the 2^+_1 excited state has allowed the determination of limits on the half-life for the two neutrino mode T^(2nu)_1/2(0^+ --> 2^+_1) > 1.1 x 10^21 y (at 90% C.L.) and for the neutrinoless mode T^(0nu)_1/2(0^+ --> 2^+_1) > 1.6 x 10^23 y (at 90% C.L.).Comment: 23 pages, 7 figures, 4 tables, submitted to Nucl. Phy

    Recent advances in neutrinoless double beta decay search

    Full text link
    Even after the discovery of neutrino flavour oscillations, based on data from atmospheric, solar, reactor, and accelerator experiments, many characteristics of the neutrino remain unknown. Only the neutrino square-mass differences and the mixing angle values have been estimated, while the value of each mass eigenstate still hasn't. Its nature (massive Majorana or Dirac particle) is still escaping. Neutrinoless double beta decay (0Μ0\nu-DBD) experimental discovery could be the ultimate answer to some delicate questions of elementary particle and nuclear physics. The Majorana description of neutrinos allows the 0Μ0\nu-DBD process, and consequently either a mass value could be measured or the existence of physics beyond the standard should be confirmed without any doubt. As expected, the 0Μ0\nu-DBD measurement is a very difficult field of application for experimentalists. In this paper, after a short summary of the latest results in neutrino physics, the experimental status, the R&D projects, and perspectives in 0Μ0\nu-DBD sector are reviewed.Comment: 36 pages, 7 figures, To be publish in Czech Journal of Physic

    Astrophysical Axion Bounds

    Get PDF
    Axion emission by hot and dense plasmas is a new energy-loss channel for stars. Observational consequences include a modification of the solar sound-speed profile, an increase of the solar neutrino flux, a reduction of the helium-burning lifetime of globular-cluster stars, accelerated white-dwarf cooling, and a reduction of the supernova SN 1987A neutrino burst duration. We review and update these arguments and summarize the resulting axion constraints.Comment: Contribution to Axion volume of Lecture Notes in Physics, 20 pages, 3 figure

    Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at sqrt(s) = 7 TeV

    Get PDF
    Results are presented from a search for a W' boson using a dataset corresponding to 5.0 inverse femtobarns of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at sqrt(s)=7 TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W' to t b, leading to a final state signature with a single lepton (e, mu), missing transverse energy, and jets, at least one of which is tagged as a b-jet. A W' boson that couples to fermions with the same coupling constant as the W, but to the right-handed rather than left-handed chiral projections, is excluded for masses below 1.85 TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge coupling for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits.Comment: Submitted to Physics Letters B. Replaced with version publishe

    Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment

    Get PDF
    This paper describes an analysis of the angular distribution of W->enu and W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and the missing transverse energy, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw > 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour, are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017 +/- 0.030, where the first uncertainties are statistical, and the second include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables, revised author list, matches European Journal of Physics C versio
    • 

    corecore