10,311 research outputs found
Bound states near a moving charge in a quantum plasma
It is investigated how the shielding of a moving point charge in a
one-component fully degenerate fermion plasma affects the bound states near the
charge at velocities smaller than the Fermi one. The shielding is accounted for
by using the Lindhard dielectric function, and the resulting potential is
substituted into the Schr\"odinger equation in order to obtain the energy
levels. Their number and values are shown to be primarily determined by the
value of the charge and the quantum plasma coupling parameter, while the main
effect of the motion is to split certain energy levels. This provides a link
between quantum plasma theory and possible measurements of spectra of ions
passing through solids.Comment: Published in EPL, see
http://epljournal.edpsciences.org/articles/epl/abs/2011/09/epl13478/epl13478.htm
Instability and Evolution of Nonlinearly Interacting Water Waves
We consider the modulational instability of nonlinearly interacting
two-dimensional waves in deep water, which are described by a pair of
two-dimensional coupled nonlinear Schroedinger equations. We derive a nonlinear
dispersion relation. The latter is numerically analyzed to obtain the regions
and the associated growth rates of the modulational instability. Furthermore,
we follow the long term evolution of the latter by means of computer
simulations of the governing nonlinear equations and demonstrate the formation
of localized coherent wave envelopes. Our results should be useful for
understanding the formation and nonlinear propagation characteristics of large
amplitude freak waves in deep water.Comment: 4 pages, 4 figures, to appear in Physical Review Letter
Practices and performance outcomes of green supply chain management initiatives in the garment industry
Purpose
The garments/textiles industry is the second most polluting industry in the world. However, efforts to understand and curtail its adverse environmental impacts have not been commensurate, and previous works have largely been fragmented and disjointed. This study aims to conduct a comprehensive and systematic green supply chain management (GSCM) investigation on this industry, where a multidimensional framework involving green supply chain practices and performance is developed, validated and applied.
Design/methodology/approach
A framework consisting of 12 constructs (8 on practices and 4 on performance) and their underlying measures were developed through an extensive literature review. A survey methodology was used to obtain responses from 403 garment-manufacturing firms in Bangladesh, one of the leading garment producers in the world. Confirmatory factor analysis and structural equation modelling were used first to validate the first- and second-order constructs and then test the hypothesized relationships.
Findings
Internal environmental management and cooperation with stakeholders were identified as necessary precursors for implementing the second-order green supply chain practices comprising green design, green purchasing, green manufacturing, green transportation, green facilities and end-of-life management. The implementation of green supply chain practices was found to have a (direct) positive impact on environmental, economic and operational performance and an indirect positive impact on organizational performance. Similarly, both economic and operational performance was found to impact organizational performance positively. Surprisingly, a negative relationship (albeit low) was observed between environmental and organizational performance. Also, garment-manufacturing firms were found to have been unable to translate their IEM capabilities into strategic and long-term cooperation with stakeholders.
Research limitations/implications
The study fills a gap in the literature about applying/implementing GSCM in the garment industry. Future studies in the garment industry and elsewhere could utilize the framework to understand further the synergistic impact of green supply chain practices on performance.
Practical implications
The findings provide practitioners, policymakers and organizations associated with the garment industry with critical insights on the various opportunities and challenges in adopting GSCM. Also, the positive impact of green supply chain practices on performance could provide the impetus for manufacturing firms to adopt GSCM.
Originality/value
A comprehensive GSCM investigation on the garment industry has not been previously attempted and constitutes the novelty of this work. Also, Bangladesh is the second-largest garment exporter worldwide, making this study contribution even more valuable
Perinatal and maternal outcome in meconium stained amnioticfluid (thin and thick) at dhiraj general hospital, a rural tertiary health centre
Background: To determine the perinatal outcome of with Meconium-stained amniotic fluid (MSAF) compared with clear amniotic fluid at Dhiraj Hospital.Methods: A prospective observational study was carried out in obstetrics and gynaecology department of Dhiraj Hospital, Sumandeep Vidyapeeth from March 2021 to August 2021. All patients fulfilling inclusion and exclusion criteria as mentioned above were taken for the study. All the categorial variables were analysed independently with the help of chi square test and fisher’s exact test and all the continuous variables were analysed with independent ‘t test’.Results: Out of 500 patients selected for the present study which had inclusion criteria, 13.6% were meconium stained out of which 50 (73.5%) cases had thin meconium and 18 (26.4%) cases had thick meconium. Fetal CTG abnormalities were more common in MSAF group and were noted in 38.2% of cases which is significantly increased compared to control group with CTG abnormalities in 8.3%. The difference was significant with p value of <0.001. 32(47.0%) patients with meconium-stained amniotic fluid had normal vaginal delivery, while in control group out of 432, 360 (83.3%) delivered normally. Incidence of LSCS and assisted vaginal delivery was more in meconium-stained amniotic fluid.Conclusions: Meconium-stained amniotic fluid is associated with more frequency of operative delivery, birth asphyxia, neonatal sepsis, and neonatal intensive care unit admissions compared to clear amniotic fluid. Better perinatal outcome in clear amniotic fluid compared to meconium stained liquor
Depth Customization of DSpace: Best Practices and Techniques of Institutional Repository at IIT Kanpur, India
4th International Conference on Open RepositoriesThis presentation was part of the session : DSpace User Group PresentationsDate: 2009-05-21 08:30 AM – 10:00 AMRealizing the importance and magnitude of Institutional Repository and global visibility and further research scope, Indian Institute of Technology Kanpur, India has intensively planned and designed a full fledged IR project started in mid 2005. Considering the various characteristics and strategies we have designed a well defined and distinct roadmap for establishing our IR in two phases. In the first phase we have planned the mass digitization of entire theses collection of Masters and Doctoral Dissertations produced from 1963 spanning one million pages with their complex content. The content management and uploading to the content server with extracted metadata encoded in XML from our existing server by an in-house developed script is being organised effectively ensuring adequate quality checking of these pages. Initially manual submission for theses was in place. Now a provision has been made available to researchers to submit their theses online even without submitting any hardcopy in the library. The second phase is conceived of digitizing scholarly publications other than theses from our academic community. Its coverage is extremely appreciable in number and strategy we are using for our IR. Excellent feature of our system is the depth customization of DSpace at several places incorporating enhanced features. We discovered that default features offered by even the latest version of DSpace are not sufficient and adequate for academic community to establish their IR system in its full functionality so as to deliver the right information to the right user at the time it is needed. After a detailed study and research we have incorporated significant features like workflow, additional browse and search options, cross-collection search, linking to keywords/subject/homepage/citation, total count of items in respect of supervisor/subject/citation. Additionally, login user authentication from central database, IP based access restrictions, embargo and encryption on the bit stream are also provided. Redesigned feedback form has also been provided to improve its scope and functionalities of our system. These are unique features of our IR system and these enhanced features may be useful to any system in identical academic environment using DSpace to power their Institutional Repositories.Indian Institute of Technology Kanpur, Indi
Broadband study of blazar 1ES 1959+650 during flaring state in 2016
Aim : The nearby TeV blazar 1ES 1959+650 (z=0.047) was reported to be in
flaring state during June - July 2016 by Fermi-LAT, FACT, MAGIC and VERITAS
collaborations. We studied the spectral energy distributions (SEDs) in
different states of the flare during MJD 57530 - 57589 using simultaneous
multiwaveband data to understand the possible broadband emission scenario
during the flare. Methods : The UV/optical and X-ray data from UVOT and XRT
respectively on board Swift and high energy -ray data from Fermi-LAT
are used to generate multiwaveband lightcurves as well as to obtain high flux
states and quiescent state SEDs. The correlation and lag between different
energy bands is quantified using discrete correlation function. The synchrotron
self Compton (SSC) model was used to reproduce the observed SEDs during flaring
and quiescent states of the source. Results : A decent correlation is seen
between X-ray and high energy -ray fluxes. The spectral hardening with
increase in the flux is seen in X-ray band. The powerlaw index vs flux plot in
-ray band indicates the different emission regions for 0.1 - 3 GeV and
3-300 GeV energy photons. Two zone SSC model satisfactorily fits the observed
broadband SEDs. The inner zone is mainly responsible for producing synchrotron
peak and high energy -ray part of the SED in all states. The second
zone is mainly required to produce less variable optical/UV and low energy
-ray emission. Conclusions : Conventional single zone SSC model does
not satisfactorily explain broadband emission during observation period
considered. There is an indication of two emission zones in the jet which are
responsible for producing broadband emission from optical to high energy
-rays.Comment: 11 pages, 12 figures, Accepted in A&
Components of the dilepton continuum in Pb+Pb collisions at TeV
The dilepton invariant mass spectrum measured in heavy-ion collisions
includes contributions from important QGP probes such as thermal radiation and
the quarkonium (, and ) states. Dileptons coming from
hard scattering, the Drell-Yan process, contribute in all mass
regions. In heavy-ion colliders, such as the LHC, semileptonic decays of heavy
flavor hadrons provide a substantial contribution to the dilepton continuum.
The dilepton continuum can give quantitative information about heavy quark
yields and their modification in the medium and thus it is important to know
all different sources which populate the continuum.
In the present study, we calculate and production and
determine their contributions to the dilepton continuum in Pb+Pb collisions at
TeV with and without including heavy quark energy
loss. We also calculate the rates for Drell-Yan and thermal dilepton
production. The contributions to the continuum from these dilepton sources are
studied in the kinematic ranges relevant for the LHC detectors. The relatively
high cutoff for single leptons excludes most dileptons produced by the
thermal medium. Heavy flavors are the dominant source of dilepton production in
all the kinematic regimes except at forward rapidities where Drell-Yan start
dominating in high mass range beyond 10 GeV/.Comment: 18 pages, 9 figure
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