285 research outputs found

    How Bio-physical Impacts of Campsite-Use affect Camping Experiences at Highly-visited National Parks of Sri Lanka

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    With escalating demand for wildlife tourism in Sri Lanka’s National Parks, the visitor interest on camping in designated campsites inside National Parks is also on the rise. However, unplanned recreational uses such as camping in natural areas can induce significant and often localized resource impacts that can affect soil, vegetation, wildlife, and water, with severity of such impacts varying depending on the intensity of use. Limited or no published research have attempted to assess the camp-site users’ perceptions on bio-physical impacts of campsite use in the Sri Lankan context. Therefore, this study evaluated the campers’ perception on environmental impacts of campsite use in highly-visited National Parks in the dry zone of Sri Lanka. Campsite user characteristics, visitor motivations, behaviors and how visitor experience is affected by visible biophysical impacts at campsites were evaluated using a structured questionnaire. The survey also gathered management actions perceived by campsite users to minimize such environmental impacts. The questionnaire was administered over-the-phone with a total of 202 individuals who had a camping experience within a period of less than 12 months from the date of contact, responding to the survey (response rate of 56.1%). Results revealed that “to be in a natural setting” as the main motivation for camping in National Parks while wildlife viewing and photography were the most popular activities of campers. Well-educated middle-aged males dominated the camping visitor segment. Based on the visitor behaviors and underlying visitor motivations derived through a Factor Analysis, the study further identified three distinct segments of campsite users: Eco-tourists, Prestige seekers, and Adventure seekers. Results further indicated that presence of litter, vandalism activities, vehicle related impacts and current solid waste disposal practices in campsites are negatively affecting visitor experience. Respondents in general, especially the well-educated high income visitor segment exhibited environmentally responsible behaviors during camping. With respect to visitor perceptions on future management of campsites, respondents approved management measures aimed at assuring the ecological integrity of campsites while disapproving substantial infrastructure development within campsites. Study results overall highlights the importance of managing biophysical impacts in campsites to provide a high quality visitor experience, while sustainably managing tourism activities in National Parks. Potential management implications are further discussed.Keywords: Wildlife tourism, Camping, Recreation ecology, Campsite user survey, Ecotouris

    Hotel Green Implementation for Future

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    The online hotel management system was designed for the client hotel green, colombo, sri lanka. Currently, the client uses a manual system for management purposes where employees handle large amounts of data manually. The proposed system allows users to store and manipulated all the data in their database making their data handling process very effective. The proposed system is developed to cover the process of the hotel such as employee management, resource management, food management, rooms management, and user account management. The admin adds and updates the available rooms and foods, and customers can check the available rooms and order foods through the system. Admin adds, updates, and deletes employee details. Admin can mark the attendance of the employees. Admin can search relevant details. Admin can view details of all customers. The customers register and log in to the system.  Customers can update and delete their accounts. A web application was developed to ensure that the customers of the hotel can make orders and reservations online. The system reduces data manipulation errors in the current process, resulting in considerable development in human resource utilization. It improves the client's relationship with their customers gaining profit for the business. The system is user-friendly, reliable, and efficient and its statistics all the customer requirements

    Liquid-phase approach to glass-microfiber-reinforced sulfide solid electrolytes for all-solid-state batteries

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    Deformable, fast-ion conducting sulfides enable the construction of bulk-type solid-state batteries that can compete with current Li-ion batteries in terms of energy density and scalability. One approach to optimizing the energy density of these cells is to minimize the size of the electrolyte layer by integrating the solid electrolyte in thin membranes. However, additive-free thin membranes, as well as many membranes based on preprepared scaffolds, are difficult to prepare or integrate in solid cells on a large scale. Here, we propose a scalable solution-based approach to produce bulk-type glass-microfiber-reinforced composites that restore the deformability of sulfide electrolytes and can easily be shaped into thin membranes by cold pressing. This approach supports both the ease of preparation and enhancement of the energy density of sulfide-based solid-state batteries

    Time and length scales in supercooled liquids

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    We numerically obtain the first quantitative demonstration that development of spatial correlations of mobility as temperature is lowered is responsible for the ``decoupling'' of transport properties of supercooled liquids. This result further demonstrates the necessity of a spatial description of the glass formation and therefore seriously challenges a number of popular alternative theoretical descriptions.Comment: 4 pages, 4 figs; improved version: new refs and discussion

    Jamming at Zero Temperature and Zero Applied Stress: the Epitome of Disorder

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    We have studied how 2- and 3- dimensional systems made up of particles interacting with finite range, repulsive potentials jam (i.e., develop a yield stress in a disordered state) at zero temperature and applied stress. For each configuration, there is a unique jamming threshold, ϕc\phi_c, at which particles can no longer avoid each other and the bulk and shear moduli simultaneously become non-zero. The distribution of ϕc\phi_c values becomes narrower as the system size increases, so that essentially all configurations jam at the same ϕ\phi in the thermodynamic limit. This packing fraction corresponds to the previously measured value for random close-packing. In fact, our results provide a well-defined meaning for "random close-packing" in terms of the fraction of all phase space with inherent structures that jam. The jamming threshold, Point J, occurring at zero temperature and applied stress and at the random close-packing density, has properties reminiscent of an ordinary critical point. As Point J is approached from higher packing fractions, power-law scaling is found for many quantities. Moreover, near Point J, certain quantities no longer self-average, suggesting the existence of a length scale that diverges at J. However, Point J also differs from an ordinary critical point: the scaling exponents do not depend on dimension but do depend on the interparticle potential. Finally, as Point J is approached from high packing fractions, the density of vibrational states develops a large excess of low-frequency modes. All of these results suggest that Point J may control behavior in its vicinity-perhaps even at the glass transition.Comment: 21 pages, 20 figure

    Plastic Flow in Two-Dimensional Solids

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    A time-dependent Ginzburg-Landau model of plastic deformation in two-dimensional solids is presented. The fundamental dynamic variables are the displacement field \bi u and the lattice velocity {\bi v}=\p {\bi u}/\p t. Damping is assumed to arise from the shear viscosity in the momentum equation. The elastic energy density is a periodic function of the shear and tetragonal strains, which enables formation of slips at large strains. In this work we neglect defects such as vacancies, interstitials, or grain boundaries. The simplest slip consists of two edge dislocations with opposite Burgers vectors. The formation energy of a slip is minimized if its orientation is parallel or perpendicular to the flow in simple shear deformation and if it makes angles of ±π/4\pm \pi/4 with respect to the stretched direction in uniaxial stretching. High-density dislocations produced in plastic flow do not disappear even if the flow is stopped. Thus large applied strains give rise to metastable, structurally disordered states. We divide the elastic energy into an elastic part due to affine deformation and a defect part. The latter represents degree of disorder and is nearly constant in plastic flow under cyclic straining.Comment: 16pages, Figures can be obtained at http://stat.scphys.kyoto-u.ac.jp/index-e.htm

    It Is Hot in the Sun: Antarctic Mosses Have High Temperature Optima for Photosynthesis Despite Cold Climate

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    The terrestrial flora of Antarctica’s frozen continent is restricted to sparse ice-free areas and dominated by lichens and bryophytes. These plants frequently battle sub-zero temperatures, extreme winds and reduced water availability; all influencing their ability to survive and grow. Antarctic mosses, however, can have canopy temperatures well above air temperature. At midday, canopy temperatures can exceed 15°C, depending on moss turf water content. In this study, the optimum temperature of photosynthesis was determined for six Antarctic moss species: Bryum pseudotriquetrum, Ceratodon purpureus, Chorisodontium aciphyllum, Polytrichastrum alpinum, Sanionia uncinata, and Schistidium antarctici collected from King George Island (maritime Antarctica) and/ or the Windmill Islands, East Antarctica. Both chlorophyll fluorescence and gas exchange showed maximum values of electron transport rate occurred at canopy temperatures higher than 20°C. The optimum temperature for both net assimilation of CO2 and photoprotective heat dissipation of three East Antarctic species was 20–30°C and at temperatures below 10°C, mesophyll conductance did not significantly differ from 0. Maximum mitochondrial respiration rates occurred at temperatures higher than 35°C and were lower by around 80% at 5°C. Despite the extreme cold conditions that Antarctic mosses face over winter, the photosynthetic apparatus appears optimised to warm temperatures. Our estimation of the total carbon balance suggests that survival in this cold environment may rely on a capacity to maximize photosynthesis for brief periods during summer and minimize respiratory carbon losses in cold conditions.Alicia V. Perera-Castro, Melinda J. Waterman, Johanna D. Turnbull, Michael B. Ashcroft, Ella McKinley, Jennifer R. Watling, Jessica Bramley-Alves, Angelica Casanova-Katny, Gustavo Zuniga, Jaume Flexas, and Sharon A. Robinso

    Alternative Methods to Finding Patterns in HiRes Stereo Data

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    In this paper Ultra High Energy Cosmic Rays UHECRs data observed by the HiRes fluorescence detector in stereo mode is analyzed to search for events in the sky with an arrival direction lying on a great circle. Such structure is known as the arc structure. The arc structure is expected when the charged cosmic rays pass through the galactic magnetic field. The arcs searched for could represent a broad or a small scale anisotropy depending on the proposed source model for the UHECRs. The Arcs in this paper are looked for using Hough transform were Hough transform is a technique used to looking for patterns in images. No statistically significant arcs were found in this study

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

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    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

    Search for the standard model Higgs boson decaying into two photons in pp collisions at sqrt(s)=7 TeV

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    A search for a Higgs boson decaying into two photons is described. The analysis is performed using a dataset recorded by the CMS experiment at the LHC from pp collisions at a centre-of-mass energy of 7 TeV, which corresponds to an integrated luminosity of 4.8 inverse femtobarns. Limits are set on the cross section of the standard model Higgs boson decaying to two photons. The expected exclusion limit at 95% confidence level is between 1.4 and 2.4 times the standard model cross section in the mass range between 110 and 150 GeV. The analysis of the data excludes, at 95% confidence level, the standard model Higgs boson decaying into two photons in the mass range 128 to 132 GeV. The largest excess of events above the expected standard model background is observed for a Higgs boson mass hypothesis of 124 GeV with a local significance of 3.1 sigma. The global significance of observing an excess with a local significance greater than 3.1 sigma anywhere in the search range 110-150 GeV is estimated to be 1.8 sigma. More data are required to ascertain the origin of this excess.Comment: Submitted to Physics Letters
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