32,999 research outputs found

    Measurement of the LCG2 and glite file catalogue's performance

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    When the Large Hadron Collider (LHC) begins operation at CERN in 2007 it will produce data in volumes never before seen. Physicists around the world will manage, distribute and analyse petabytes of this data using the middleware provided by the LHC Computing Grid. One of the critical factors in the smooth running of this system is the performance of the file catalogues which allow users to access their files with a logical filename without knowing their physical location. This paper presents a detailed study comparing the performance and respective merits and shortcomings of two of the main catalogues: the LCG File Catalogue and the gLite FiReMan catalogue

    Identifying information seeking behaviours of low and high literacy users: combined cognitive task analysis.

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    Motivation – According to the UK’s National Skills for Life survey carried out in 2003, 16% or equivalent to 5.2 million of the UK population presented low levels of literacy (Williams, et al. 2003). In this study we investigate the differences in information seeking behaviours between low and high literacy users of an on-line social service system. Research approach – Ten volunteers participated in the study. Using the National Skills for Life Survey, five were classified as high literacy; five as low literacy. All participants were asked to think-aloud whilst carrying out the information search using the “Adviceguide” website. The four tasks were of varying difficulty; easy, medium and difficult. Observations, video recording, and a semi structured interview technique that uses cognitive probes were used. The qualitative data were transcribed and analysed using Strauss and Corbin’s (1998) Grounded Theory and Wong and Blandford (2002) Emergent Themes Analysis approach. Findings/Design – We identified eight themes or characteristics from this study; Verification, Reading, Recovery, Trajectories, Abandon, Focus, Satisfied, and Perception. Results showed that low and high literacy users demonstrated critically different characteristics. Take away message – To better support the low and high literacy users with information seeking, we plan to look at information seeking behaviour models as theoretical lenses to analyse their behaviour from the identified characteristics (Makri, Blandford & Cox, 2008). The behaviour models will better inform the development of interface design for low and high literacy users

    Identification of MHC Class II Binders/ Non-binders using Negative Selection Algorithm

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    The identification of major histocompatibility complex (MHC) class-II restricted peptides is an important goal in human immunological research leading to peptide based vaccine design. These MHC class–II peptides are predominantly recognized by CD4+ T-helper cells, which when turned on, have profound immune regulatory effects. Thus, prediction of such MHC class-II binding peptides is very helpful towards epitope-based vaccine design. HLA-DR proteins were found to be associated with autoimmune diseases e.g. HLA-DRB1*0401 with rheumatoid arthritis. It is important for the treatment of autoimmune diseases to determine which peptides bind to MHC class II molecules. The experimental methods for identification of these peptides are both time consuming and cost intensive. Therefore, computational methods have been found helpful in classifying these peptides as binders or non-binders. We have applied negative selection algorithm, an artificial immune system approach to predict MHC class–II binders and non-binders. For the evaluation of the NSA algorithm, five fold cross validation has been used and six MHC class–II alleles have been taken. The average area under ROC curve for HLA-DRB1*0301, DRB1*0401, DRB1*0701, DRB1*1101, DRB1*1501, DRB1*1301 have been found to be 0.75, 0.77, 0.71, 0.72, and 0.69, and 0.84 respectively indicating good predictive performance for the small training set

    Giant magnetothermal conductivity and magnetostriction effect in charge ordered Nd0.8_{0.8}Na0.2_{0.2}MnO3_{3} compound

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    We present results on resistivity (ρ\rho), magnetization (MM), thermal conductivity (κ\kappa), magnetostriction (ΔLL(0)\frac{\Delta L}{L(0)}) and specific heat (CpC_{p}) of charge-orbital ordered antiferromagnetic Nd0.8_{0.8}Na0.2_{0.2}MnO3_{3} compound. Magnetic field-induced antiferromagnetic/charge-orbital ordered insulating to ferromagnetic metallic transition leads to giant magnetothermal conductivity and magnetostriction effect. The low-temperature irreversibility behavior in ρ\rho, MM, κ\kappa and ΔLL(0)\frac{\Delta L}{L(0)} due to field cycling together with striking similarity among the field and temperature dependence of these parameters manifest the presence of strong and complex spin-charge-lattice coupling in this compound. The giant magnetothermal conductivity is attributed mainly to the suppression of phonon scattering due to the destabilization of spin fluctuations and static/dynamic Jahn-Teller distortion by the application of magnetic field.Comment: 4 Pages, 4 Figure

    Visible and near infrared spectroscopy of Hayabusa re-entry using semi-autonomous tracking

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    A ground-based tracking camera and co-aligned slit-less spectrograph were used to measure the spectral signature of visible radiation emitted from the Hayabusa capsule as it entered into the Earth's atmosphere in June 2010. Good quality spectra were obtained that showed the presence of radiation from the heat shield of the vehicle and the shock-heated air in front of the vehicle. An analysis of the black body nature of the radiation concluded that the peak average temperature of the surface was about (3100±100) K

    M-GEAR: Gateway-Based Energy-Aware Multi-Hop Routing Protocol for WSNs

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    In this research work, we advise gateway based energy-efficient routing protocol (M-GEAR) for Wireless Sensor Networks (WSNs). We divide the sensor nodes into four logical regions on the basis of their location in the sensing field. We install Base Station (BS) out of the sensing area and a gateway node at the centre of the sensing area. If the distance of a sensor node from BS or gateway is less than predefined distance threshold, the node uses direct communication. We divide the rest of nodes into two equal regions whose distance is beyond the threshold distance. We select cluster heads (CHs)in each region which are independent of the other region. These CHs are selected on the basis of a probability. We compare performance of our protocol with LEACH (Low Energy Adaptive Clustering Hierarchy). Performance analysis and compared statistic results show that our proposed protocol perform well in terms of energy consumption and network lifetime.Comment: IEEE 8th International Conference on Broadband and Wireless Computing, Communication and Applications (BWCCA'13), Compiegne, Franc

    Role of non-timber forest products in sustaining forest-based livelihoods and rural households' resilience capacity in and around protected area- a Bangladesh study

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    People in developing world derive a significant part of their livelihoods from various forest products, particularly non-timber forest products. This article attempts to explore the contribution of NTFPs in sustaining forest-based rural livelihood in and around a protected area of Bangladesh, and their potential role in enhancing households resilience capacity. Based on empirical investigation our study revealed that, local communities gather a substantial amount of NTFPs from national park despite the official restrictions. 27 percent households of the area received at least some cash benefit from the collection, processing and selling of NTFPs, and NTFPs contribute as HHs primary, supplementary and emergency sources of income. NTFPs also constituted an estimated 19 percent of HHs net annual income, and were the primary occupation for about 18 percent of the HHs. HHs dependency on nearby forests for various NTFPs varied vis-a-vis their socio-economic condition as well as with their location from the park. Based on our case study the article also offers some clues for improving the situation in PA.Comment: To appear in Journal of Environmental Planning and Management, 201
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