6,350 research outputs found

    Turbulent flow structures and scour hole characteristics around circular bridge piers over non-uniform sand bed channels with downward seepage

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    Bridges play an important role in the transportation of goods and people across rivers. In civil engineering, one of the most important issues is to protect bridge piers from collapse. In fact, their foundation may be threatened by localized scour, as a result of the flow constriction of the cross-sectional area, and the subsequent increase of the flow velocity [1]. Thus, in order to ensure the protection of such structures, it is of a high priority to predict the flow field and sediment transport around the bridge piers. Many researchers have studied the vortice systems around piers, stating that they primarily aect the local scour [2–6]. Melville and Coleman [5] stated that the flow field around a bridge pier is characterized by down-flow, surface roller, and wake vortices, such as the horseshoe vortex, at the base of the pier, and wake vortices behind the pier. According to Melville [2] and Chiew [4], a horseshoe vortex increases the flow velocity near the bed, and the wake vortex carries the eroded bed material downstream. However, the eect of the pier on flow separation, and the consequent sediment transport, depends on turbulence. Some studies have investigated the stochastics nature of turbulent flow around a pier [2,7–11], but there still remains a lack information concerning the trend of higher order moments for the fluctuating velocities

    Turbulent Flow Structure in Developing and Fully-Developed Flows under the Impact of Downward Seepage

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    This work experimentally investigates the turbulent flow characteristics of developing and fully-developed flows over a rough bed channel that is subjected to downward seepage. Instantaneous 3D velocities were collected using an acoustic Doppler velocimeter (ADV) in the developing and fully-developed flow regions, along the channel centerline, to analyze different turbulent statistics. Observations revealed that the streamwise and vertical velocities were higher in developing flows, whereas the Reynolds shear stresses, and turbulence intensities, were smaller. The downward seepage would affect the velocity distributions and flow depth in both the developing and fully-developed regions. Therefore, new equations to represent the distribution of the turbulence intensities were proposed, and a comparison with the current literature is provided. The investigation of the Reynolds stress anisotropy tensors concludes that the degree of anisotropy in fully-developed flows is lower than for developing flows

    Bibliographics for the 983 eprints in the live archives of E-LIS : trends and status report up to 7th July 2004, based on author-self-archiving metadata

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    The priority for ideas and philosophy related to "Network Theory" have been traced back and documented by Braun(2004),and credit goes to Karinthy(1929).The IT has empowered to realise it, as the most practical phenomena and it is no more a humour. The OAI (Open Archives Initiatives)and ACIS (Academic Contributor Information System)are progressive in the direction ,which may lead to realise the "Collective Genius" at global level. Focus of present study is on Author-Self-Archiving (A-S-A)Metadata of the 983 Eprints in the Live Archives of the E-LIS (EPrints of Library and Information Science),which were approved till 7th July 2004.The A-S-A Metadata was used for librametric analysis. Self-explanatory bibliographics are illustrated.The highlights include: Conference papers (34%); highest approval, June 2004 (28%); published archives (76%);not refereed (52%); not in public domain (60%); highest self-archiving-author (De Robbio, Antonella).The Nos. of EPrints having single JITA domain specifications were: Theoretical and general aspects of libraries and information(27); Information use and sociology of information(80);Users,literacy and reading(13);Libraries as physical collections(30);Publishing and legal issues(57);Management(13);Industry, profession and education(36);Information sources, supports, channels(113) ; Information treatment for information services, Information functions and techniques (101); Technical services libraries, archives and museums(25); Housing technologies(1); Information technology and library technology(92); and Inter-domainery (395) i.e. having specifications of two or more than two JITA classes

    A Unified Shell model for Buoyancy-Driven Turbulence

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    We construct a unified shell model for stably stratified and convective turbulence. Shell model simulation of stably stratified flow in turbulent regime exhibit Bolgiano-Obukhbov (BO) scaling in which the kinetic energy spectrum varies as k11/5k^{-11/5}. However, simulation of convective turbulence shows Kolmogorov's spectrum. These results are consistent with the direct numerical simulations of Kumar {\em et al.} [Phys. Rev. E {\bf 90}, 023016 (2014)]. We also observe a dual scaling (k11/5k^{-11/5} and k5/3k^{-5/3}) for a limited range of parameters in stably stratified flow

    Variability of Energy Dissipation and Shear Rate with Geometry in Unbaffled Surface Aerator

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    mixing in surface aerators. At constant dynamic variables (rotational speed), both and γ are greatly affected by the geometric parameters (impeller diameter, cross-sectional area of the tank, liquid height, rotor blade length and immersion height). By doing numerical computation by VISIMIX ®, present work analyzes the effect of non-dimensional (which is non-dimensionalized through rotor diameter) geometric parameters on e and g. With an increase in liquid height, there is an increase in the case of energy dissipation and shear rate values. In the case of tank area and blade length, it is vice versa. Energy dissipation and shear rate are not affected by the variation in immersion height of the impelle

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    Story of the Story-Teller: A Conversation with Ramendra Kumar

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    Ramendra Kumar (Ramen) is an award-winning writer, storyteller and inspirational speaker with 42 books to his name.  Ramen’s writings have been published by many of the leading publishers in the county and translated into 30 languages. They have found a place in several textbooks and anthologies. He has written across all genres ranging from picture books to adult fiction, satire, poetry, travelogues, biographies and on issues related to parenting and relationships. He has been invited to literary festivals held in Denmark, Greece, Sharjah, Sri Lanka as well Indian events including the prestigious Jaipur Litfest to conduct storytelling sessions and creative writing workshops. He has also been empanelled by Pearson India Education Services as well as several schools to conduct workshops. He was nominated as a Jury Member for the Best Children’s Author Category of The Times of India’s ‘Women AutHer’ Awards 2020. Many of his stories have been showcased by popular audio streaming, apps both within and outside the country, such as Spotify, Gaatha, Talking Stories Radio – London et al. An Engineer & an MBA, Ramen was serving as the General Manager (Corporate Communications), SAIL, Rourkela Steel Plant, when he took Voluntary Retirement to pursue his passion, in August 2020. To know more about the writer, you can visit his website www.ramendra.in & his page on Wikipedia.  Dr. Sagar Kumar Sharma interviews the author and unfolds the pages of his life. &nbsp

    NOTICE!!! This person (known as Ashwin Kumar) plagiarized the text titled: "Using phenomenological research methods in qualitative health research"

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    EDITORIAL NOTICE: 1. This publication has been removed due to detected plagiarism by the editorial. 2. If you have cited, you MUST UPDATE your reference with the following original article: Wojnar, Danuta, and Kristen Swanson. “Phenomenology An Exploration”. Journal of holistic nursing : official journal of the American Holistic Nurses’ Association 25 (01 October 2007): 172-80; discussion 181. https://doi.org/10.1177/0898010106295172.     _________________________________________  3. Submitter's Profile Record (the thief, the plagiariser): Name: Ashwin KumarURL: http://www.freewebs.com/ak2146Affiliation: University of Western Sydney, Australia.Country: AustraliaBio Statement:Dr. Ashwin Kumar,PO Box 571,Toongabbie,Sydney,Australia, NSW, 2146.Homepage: http://www.freewebs.com/ak2146Email: [email protected] [email protected]: 0432-622-147Skype Internet Phone ID: ak2146 Dr. Ashwin Kumar (BA, MA (Distinction), PhD) is an academic researcher whose research interests and areas of expertise include: Complementary and alternative medicine (CAM), ageing and social gerontology, sociology, social anthropology, sociology of care, public health, health promotion, Indigenous health, migrant and refugee health, disability and chronic illness. Ashwin is the author of 8 books and numerous academic journal articles in the field of public health, health sociology and anthropology of health and illness. His books: The Lived Experience of Caring; The Lived Experience of Ageing; The Lived Experience of Using Complementary and Alternative Medicine; Doing Sociology; The Basics of Sociology; Plain English Writing; Research and Writing Skills and Writing Effective Essays are available at:  http://www.amazon.com/s/ref=ntt_athr_dp_sr_1?_encoding=UTF8&sort=relevancerank&search-alias=books&field-author=PhD.%20Ashwin%20Kumar  My homepage: http://www.freewebs.com/ak2146  ________________________________________

    Multivariate Quantitative Representativeness and Constituency Analysis of Ecological Observation Networks

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    Cite this code as: Kumar, J. (2023). Multivariate Quantitative Representativeness and Constituency Analysis of Ecological Observation Networks (Version 1.0) [Computer software]. https://doi.org/10.5281/zenodo.8048530 Multivariate Quantitative Representativeness and Constituency Analysis of Ecological Observation Networks Author: Jitendra (Jitu) Kumar ([email protected]), Oak Ridge National Laboratory Regional and global ecological research networks, representing coordinated and standardized as well as adhoc networks of observation sites, provide valuable observations necessary for ecological modeling and synthesis studies. Studies conducted across observational networks strive to scale up their results to larger areas, trying to reach conclusions that are valid throughout regional, continental, and even global scales. Network representativeness and constituency can show how well conditions at those locations represent conditions elsewhere within a larger area containing the network and can be used to help scale-up results over larger regions. Representativeness: Euclidean distance between two sites plotted in multivariate environmental space can be used as an inverse measure of multivariate similarity to quantify representativeness. Close sites in environmental space have a similar combination of environmental factors, and therefore are highly representative of each other. Constituency: For any site in the network, its Constituency represent all locations that are best represented by the multivariate environmental drivers at that site. Code Compilation: make Edit the ```makefile``` as needed for your platform. CC=gcc CFLAGS= -O3 hpea: network_representativeness.o\ utility.o (CC)(CC) (CFLAGS) *.o -lm -o network_representativeness .o: (CC)(CC) (CFLAGS) -c $< clean: \rm *.o network_representativeness Running the representativeness analysis: Usage: network_representativeness -infile input data file [ASCII] -coordsfile coordinate file name -clustfile coordinate file name [OPTIONAL -- must be used with -siteclustfile] -sitefile site data file name -siteclustfile site data file name [OPTIONAL -- must be used with -clustfile] -nsites No. of sites -minmaxfile minmax file name -outfile output file name -nrows No. of rows in input data -ncols No. of variables -details [OPTIONAL -- turn on output representativeness for each site, default is to write network representativeness and constituency only.] -help program usage help. Publications using ```network_reprentativeness``` code: Kumar, J., Coffin, A. W., Baffaut, C., Ponce-Campos, G., Witthaus, L., and Hargrove, W. W. (2023) "Quantitative Representativeness and Constituency of the Long-Term Agroecosystem Research Network, and Analysis of Complementarity with Other Existing Ecological Networks", Environmental Management (in press) M. M. T. A. Pallandt, J. Kumar, M. Mauritz, E. A. G. Schuur, A.-M. Virkkala, G. Celis, F. M. Hoffman, and M. Göckede. Representativeness assessment of the pan-arctic eddy covariance site network and optimized future enhancements. Biogeosciences, 19(3):559--583, 2022. https://doi.org/10.5194/bg-19-559-2022 J. Kumar, F. M. Hoffman, W. W. Hargrove, and N. Collier. Understanding the representativeness of FLUXNET for upscaling carbon flux from eddy covariance measurements. Earth System Science Data Discussion, 2016:1--25, August 2016. https://doi.org/10.5194/essd-2016-36.If you use this software, please cite it as below. Kumar, J. (2023). Multivariate Quantitative Representativeness and Constituency Analysis of Ecological Observation Networks (Version 1.0) [Computer software]. https://doi.org/10.5281/zenodo.804853
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