276 research outputs found
Autonomic management of data streaming and in-transit processing for data intensive scientific workflows
No full textHigh-performance computing is playing an important role in science and engineering and is enabling highly accurate simulations, which provide insights into complex physical phenomena. A key challenge is managing the enormous data volumes and high data rates associated with these applications, so as to have minimal impact on the execution of the simulations. Furthermore these applications are based on seamless interactions and coupling between multiple and potentially distributed computational, data and information services. This requires addressing the natural mismatches in the ways data is represented in different workflow components and on a variety of machines, and being able to "outsource" the required data manipulation and transformation operations to less expensive commodity resources "in-transit". Satisfying these requirements is challenging, especially in large-scale and highly dynamic in-transit environments with shared computing and communication resources, resource heterogeneity in terms of capability, capacity, and costs, and where application behaviors, needs, and performance are highly variable.
In this research we address these requirements by developing a data streaming and in-transit data manipulation framework that provides mechanisms as well as the management strategies for large scale and wide-area data intensive scientific and engineering workflows. The main objectives of this research are: (1) developing an end-to-end QoS management framework for data intensive applications so that it is able to provide robust underlying support for asynchronous, high-throughput, low-latency data streaming, and (2) effectively and opportunistically utilize resources in-transit for data processing, to match data mismatches between application entities executing in scientific workflows.
In this thesis, we address problem at two levels, the first or application level deals with satisfying QoS goals at the end points. Specifically, it ensures that the data is delivered in a timely manner, with no loss at the source or destination, and with minimal storage requirements at the end-points. The solution couples model-based limited look-ahead controllers (LLC) with rule-based managers to satisfy data streaming requirements under various operating conditions. The second or in-transit level focuses on scheduling in-transit computations and data transfer in an opportunistic manner on the in-transit overlay resources taking into account the higher level QoS goals of the source and the sink. Additionally the in-transit level management is coupled with the application level management at end points to manage QoS of grid workflows.
This research is driven by the requirements of the Fusion Simulation Project (FSP), which forms the basis of a predictive plasma edge simulation capability to support next-generation burning plasma experiments such as the International Thermonuclear Experimental Reactor (ITER). These scientific workflows require in-transit data manipulation and streaming in a wide area environment. The self-managing data streaming service developed using this approach for the FSP workflow minimizes streaming overheads on the executing simulation to about 2% of the simulation execution time, reduces buffer occupancy at the source and thus prevents data loss. Additionally experiments with self-managing data streaming and in-transit processing demonstrates that adaptive processing using this service during network congestions decreases average idle time per data block from 25% to 1%, thereby increasing utilization at critical times. Furthermore, coupling end-point and in-transit level management during congestion reduces average buffer occupancy at in-transit nodes from 80% to 60.8%, thereby reducing load and potential data loss.Ph.D.Includes bibliographical references (p. 136-143)
Comparison between Color Spaces of Vita Lumin Shade Guide with Natural Teeth in Bengaluru Population using Spectrocolorimeter: An in vivo Study
No full textABSTRACT
Aim
The aim of this study is to compare the color space of Vita Lumin shade guide (SG) with the natural teeth of the local population.
Materials and methods
A total of 100 maxillary central incisors (100 patients) were subjected to color measurement with a spectrocolorimeter. For each tooth, L*, a*, b* values were recorded. All the shade tabs of Vita Lumin SG were analyzed with a spectrocolorimeter to define the color space covered by the Vita Lumin SG. The L*a*b* values of natural teeth were plotted on separate scattered diagrams and compared.
Results
About two out of three attributes (luminance and blue spectrum) of the local population of Bengaluru displayed a broader range than those available in Vita Lumin SG.
Conclusion
The local population requires an SG with an extended range, covering a higher luminance spectrum and broader blue spectrum.
Clinical significance
Esthetic restorations require accurate shade matching with the adjacent natural teeth, SGs being the mean of shade selection and communication should be comparable to the natural teeth.
How to cite this article
Shetty RM, Bhat AN, Gupta N, Mehta D, Srivatsa G, Singh I. Comparison between Color Spaces of Vita Lumin Shade Guide with Natural Teeth in Bengaluru Population using Spectrocolorimeter: An in vivo Study. J Contemp Dent Pract 2017;18(8):683-687.
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Engineering Economical and Sustainable Solutions for the Abatement of Volatile Organic Compounds
No full textOver the last three decades, combined efforts of industries, the EPA, and automakers have helped reduce the emission of many harmful molecules such as carbon monoxide, sulfur dioxide, and particulate matter to improve air quality. However, rapid industrialization and urbanization have contributed to a significant rise in volatile organic compounds (VOCs), one of the primary air pollutants. Prolonged exposure to certain VOCs, even at concentrations as low as 0.25 ppm, is known to be carcinogenic. Therefore, the detrimental health impacts of VOCs and their increasingly stringent environmental regulations warrant continuous research to develop more effective, economical, and sustainable technologies to mitigate their emissions. In most industries, the VOCs are curtailed by combining an adsorption-desorption process using beaded activated carbon (BAC) with subsequent thermal incineration. This hybrid VOC abatement system suffers from two major limitations. First, the occurrence of strongly, or irreversibly adsorbed species in BAC, referred to as “heel”, prevents complete regeneration of the sorbent, decreasing its capacity and lifetime. Second, the massive energy requirement of the thermal incinerator increases the carbon footprint of the operation and overall operational cost.
The research presented in this dissertation provides economical and sustainable strategies to address the limitations of the hybrid abatement process described above. Using spectroscopic and thermogravimetric techniques, we aimed at understanding the factors responsible for the heel accumulation in BAC during gas-phase adsorption-desorption operation. Addressing this, the dissertation provides a facile methodology to modify the surface of the BAC through a chemical treatment to impede heel formation. This modification protocol increases the porosity of BAC by up-to 55% without altering its structural integrity. Consequently, the adsorption capacity of the BAC increased by nearly 38% while decreasing the peak desorption temperature by as much as 50°C due to lowered adsorption strength. Furthermore, this thesis explored feasible methods of regenerating the spent BAC to improve the efficacy of the industrial VOC abatement technique. This effort resulted in the invention of a unique vapor-phase regeneration technique. The lab-scale studies demonstrated that dimethyl sulfoxide vapors could be effectively used to recover nearly 82% of the adsorption capacity of the spent BAC without compromising its structural integrity.
The second phase of this research investigated the feasibility of using energy-efficient catalytic oxidation to decompose or destroy VOCs into H2O and CO2 at low temperatures. As such, the dissertation provides a roadmap to the synthesis of a novel catalyst architecture of encapsulating catalytically active noble metals in porous TiO2 support. Electron microscopic studies indicated that encapsulation helps maintain a uniform metal particle distribution (2-5 nm) and promotes metal-support interactions by maximizing interfacial sites, thereby improving catalytic activity. In addition, we discovered that subjecting the encapsulated catalyst to a post-synthesis solvothermal treatment step anchors the active metal more strongly to the support, which helps maintain superior activity under repeated uses. Finally, the thesis attempts to push the boundaries of catalytic VOC oxidation reactions via concurrent utilization of thermal energy and visible light to bring down the overall energy requirement of the VOC abatement. By encapsulating plasmonic silver nanostructures in a porous TiO2 shell resembling a core@shell morphology, we created a multifunctional material capable of generating energetic electrons upon visible light illumination. These electrons can be used in tandem with thermal energy to decompose n-butanol at viable rates at significantly reduced temperatures as low as 200°C.PhDChemical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/170068/1/bhatada_1.pd
Characterization of Enzymes Produced by Bacillus species
No full textThis Dissertation / Report is the outcome of investigation carried out by the creator(s) / author(s) at the department/division of Central Food Technological Research Institute (CFTRI), Mysore mentioned below in this page
Bajji on the Beach: Middle-Class Food Practices in Chennai’s New Beach
No full textThis book produced by a group of interdisciplinary and international researchers working on a wide variety of cities throughout Asia, Latin America and Europe, addresses, rethinks and, in some cases, abandons the notions of formal and ..
Defective interaction between Pol2p and Dpb2p, subunits of DNA polymerase epsilon, contributes to a mutator phenotype in Saccharomyces cerevisiae.
No full textMost of the prokaryotic and eukaryotic replicative polymerases are multi-subunit complexes. There are several examples indicating that noncatalytic subunits of DNA polymerases may function as fidelity factors during replication process. In this work, we have further investigated the role of Dpb2p, a noncatalytic subunit of DNA polymerase epsilon holoenzyme from Saccharomyces cerevisiae in controlling the level of spontaneous mutagenesis. The data presented indicate that impaired interaction between catalytic Pol2p subunit and Dpb2p is responsible for the observed mutator phenotype in S. cerevisiae strains carrying different mutated alleles of the DPB2 gene. We observed a significant correlation between the decreased level of interaction between different mutated forms of Dpb2p towards a wild-type form of Pol2p and the strength of mutator phenotype that they confer. We propose that structural integrity of the Pol epsilon holoenzyme is essential for genetic stability in S. cerevisiae cells
VERMITECHNOLOGY: AN ECO APPROACH OF SOLID WASTE MANAGEMENT IN RURAL AREAS
No full textOver the last few years, solid waste generation and its management has become one of the biggest major environmental concerns. Each year, human, livestock and crops produce approximately 38 Billion metric ton per year (BMTY-1) of organic waste worldwide. In India food industries, intensive livestock farming and poultry farms generate huge quantities of organic solid wastes. Utilization of these waste materials for productivity process is important for both economical and environmental reasons. Although various physical, chemical and microbiological methods of disposal of organic wastes are currently in use, these methods are time consuming and involve high costs. Therefore, there is a dire need to find out cost-effective alternative method of shorter duration particularly suited to rural conditions. In this regard, vermicomposting (VC) has been reported to be a viable cost-effective and rapid technique for the efficient management of the organic solid wastes. VC is an important aspect, as it converts waste to wealth by using cheap eco-friendly option with the activity of earthworms. Vermicompost is rich in plant nutrients, provides the entire essential nutrient element, improves soil structure, texture, aeration, water holding capacity and prevents soil erosion. Vermicompost is also rich in beneficial micro-flora such as N-fixers, P-solubilizers, cellulose decomposing micro-flora etc. Different organic wastes which are generated in villages have been converted into vermicompost by different species of earthworms include cattle dung, horse waste, pig waste, sheep waste, poultry droppings, cow slurry, kitchen waste, agricultural wastes etc. VC is especially beneficial in rural areas as it targets solid waste management and at the same time provides with chemical free organic fertilizer to enhance crop productivity, employment for rural communities, low cost and high gain technology
Detailed optical and near-infrared polarimetry, spectroscopy and broad-band photometry of the afterglow of GRB 091018 : polarization evolution
No full textFollow-up observations of large numbers of gamma-ray burst (GRB) afterglows, facilitated by the Swift satellite, have produced a large sample of spectral energy distributions and light curves, from which their basic micro- and macro-physical parameters can in principle be derived. However, a number of phenomena have been observed that defy explanation by simple versions of the standard fireball model, leading to a variety of new models. Polarimetry can be a major independent diagnostic of afterglow physics, probing the magnetic field properties and internal structure of the GRB jets. In this paper we present the first high-quality multi-night polarimetric light curve of a Swift GRB afterglow, aimed at providing a well-calibrated data set of a typical afterglow to serve as a benchmark system for modelling afterglow polarization behaviour. In particular, our data set of the afterglow of GRB 091018 (at redshift z = 0.971) comprises optical linear polarimetry (R band, 0.13-2.3d after burst); circular polarimetry (R band) and near-infrared linear polarimetry (Ks band). We add to that high-quality optical and near-infrared broad-band light curves and spectral energy distributions as well as afterglow spectroscopy. The linear polarization varies between 0 and 3per cent, with both long and short time-scale variability visible. We find an achromatic break in the afterglow light curve, which corresponds to features in the polarimetric curve. We find that the data can be reproduced by jet break models only if an additional polarized component of unknown nature is present in the polarimetric curve. We probe the ordered magnetic field component in the afterglow through our deep circular polarimetry, finding P circ < 0.15per cent (2σ), the deepest limit yet for a GRB afterglow, suggesting ordered fields are weak, if at all present. Our simultaneous R- and Ks-band polarimetry shows that dust-induced polarization in the host galaxy is likely negligible
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