3,512 research outputs found
Linear and Nonlinear Bullets of the Bogoliubov-de Gennes Excitations
We report on the focalization of Bogoliubov–de Gennes excitations of the nonlinear Schrödinger equation in the defocusing regime (Gross-Pitaevskii equation for repulsive Bose-Einstein condensates) with a spatially modulated periodic potential. Exploiting the modification of the dispersion relation induced by the modulation, we demonstrate the existence of localized structures of the Bogoliubov–de Gennes excitations, in both the linear and nonlinear regimes (linear and nonlinear “bullets”). These traveling Bogoliubov–de Gennes bullets, localized both spatially and temporally in the comoving reference frame, are robust and propagate remaining stable, without spreading or filamentation. The phenomena reported in this Letter could be observed in atomic Bose-Einstein condensates in the presence of a spatially periodic potential induced by an optical lattice.Peer ReviewedPostprint (published version
Kinetic Modelling for Tar Evolution and Formation in a Downdraft Gasifier
Biomass gasification modeling is a powerful tool
used to optimize the design of a gasifier. A detailed kinetic model
was built by the current authors [1] to predict the behavior of
air blown downdraft gasifier for a wide range of materials
within the range of (38≤C≤52) %, (5.2≤H≤7) %, and
(21.7≤O≤45) %. The model was verified and showed a good
stability for a wide range of working parameters like
equivalence ratio and moisture content. In the current research,
4 main tar species are added to the model to represent tar
formation using detailed kinetic reactions. The yield of tar
species is discussed for different zones of a gasifier based on
temperature of each zone. Mass and energy balance are
calculated. 18 different kinetic reactions are implemented in the
kinetic code to predict the optimum working conditions that
leads to the production of higher value producer gas. Results
conclude that using ER of 0.3 with moisture content levels lower
than 10% will lead to the production of higher yields of syngas
with lower amounts of tar
ERAM2 - ENERGY BASED RESOURCE ALLOCATION WITH MINIMUM RECKON AND MAXIMUM RECKON
The emerging field of cloud computing has flexibility and dominant computational architecture that offers ubiquitous services to users. It is different from traditional architecture because it accommodates resources in a unified way. Due to rapid growth in demands for providing the resources and computation in cloud environments, Resource allocation is considered as primary issues in performance, efficiency, and cost. For the provisioning of resource, Virtual Machine (VMs) is employed to reduce the response time and executing the tasks according to the available resources. The users utilize the VMs based on the characteristics of the tasks for effective usage of resources. This helps in load balancing and avoids VMs being in an idle state. Several resource allocation techniques are proposed to maximize the utility of physical resource and minimize the consuming cost of Virtual Machines (VMs). This paper proposes an Energy-Based Resource Allocation with Minimum Reckon and Maximum Reckon (ERAM2); which achieves an efficient scheduling by matching the user tasks on Resource parameters like Accessibility, Availability, Cost, Reliability, Reputation, Response time, Scalability and Throughput in the terms of Maximum Reckon and Minimum Reckon. This paper proposes an Ant Colony - Maximum Reckon and Minimum Reckon (AC-MRMR) method to consolidate all the available resource based on the pheromone value; the score is calculated for each pheromone value. When the score value exceeds Threshold limit then task migration process is carried out for optimized resource allocation of tasks
Distribution of Wigner delay time from single channel disordered systems
We consider the scattering of an electron from a semi-infinite
one-dimensional random medium. The random medium is characterized by force,
-\d V/\d L being the basic random variable. We obtain an analytical
expression for the stationary delay time () distribution
within a random phase approximation. Our result agrees with earlier analytical
expressions, where the random potential is taken to be of different kind,
indicating universality of the delay time distribution, i.e., delay time
distribution is independent of the nature of disorder.Comment: 8 pages RevTeX, no figure
Hand Vein Pattern Recognition using Natural Image Statistics
Biometrics is the science of identifying a person using physiological or behavioural characteristics. Hand vein pattern is a recent and unique biometric feature which is used for high secure authentication of individuals. The dorsal hand contains dorsal metacarpal veins, dorsal venous network, cephalic vein and basilic vein. Â This paper presents an image descriptor which uses statistical structure of natural images. In this work, stack of natural image patches are used as filters and these transform an image into integer labels describing the small-scale appearance of the image. These labels are converted into histogram and it is used for further image analysis. The feature space contains binarized statistical image features. The proposed work is tested on NCUT dataset with state-of-the-art algorithms. The experimental results demonstrate that the proposed work outperforms of the state-of-the-art algorithms with the recognition rate of 99.80 per cent.Defence Science Journal, Vol. 65, No. 2, March 2015, pp.150-158, DOI:http://dx.doi.org/10.14429/dsj.65.731
Assessment of Forest Encroachment in Shimoga District of Western Ghats, India, Using Remote Sensing and Gis
Sustainable management of Forest ecosystem is necessary as it serves the important functions such as supplementing human dietary requirements, ecological significance in terms of biodiversity conservation, flood control, water purifica-tion and micro climate regulation etc. Hence, an inventory of reserve forest in a given area is a pre-requisite for their con-servation and management. The present study is focused on RS and GIS based assessment of forest encroachment in Shimoga district of Karnataka for the years 1990, 2000 and 2010 using Landsat TM/MSS/ETM+ for 1990 and 2000, and IRS P6 LISS III for the year 2010. It’s located in the mid south western part of malnad region of Karnataka state, geographically lies between 13°27' and 14°39' N latitudes and 74°38' and 76°4'E longitudes. It covers an area of 8,482.32 km2 a apart of western ghats areas (Sahayadrihill ranges), the densely forested high hilly Malnad in the west and sparsely forested tablelands semi-malnad in the east of Karnataka state with a forest area constituting 32.66% of the total geographical area of the district. The study revealed that the encroachment in reserve forest area accounts for 282.92 km2, 257.27 km2 and 192.43 km2 for the year 2010, 2000 and 1990 respectively. Extension of cultivation is the major cause of large-scale encroachment in the district. There is no proper demarcation of the forest boundaries in some places. This has also resulted in encroachment of for-est land. It has led to forest fragmentation, loss of habitat and corridor for movement of wild animals, etc. The policy mak-ers and judiciary have stressed the need for use of recent satellite data to assess the forest encroachment in Western Ghats region. In this regard, an attempt has been made to study the two decadal forest encroachment patterns of Shimoga district. The extent of encroachment was observed to be 12.13 % in 2010. Encroachment is more prevalent in the moist and dry deciduous forests than the evergreen forests and is seen increasing day by day. This information will help for frontline forest officials to trace and book forest offences occurring in their jurisdiction and also to prevent encroachments
Design and Modeling of Tool Trajectory in C0 Continuity Concept by Importing the IGES Neutral File
A common task in geometric modeling is to interpolate a sequence of points or derivatives, sampled from a curve, with a parametric polynomial or spline curve. To do this the first step is to choose parameter values corresponding to the interpolation points. In a parametric environment, user can completely define a geometric feature with some parameters. This paper has an aim to generate a smooth tool trajectory spline for machining a workpiece. With the spline technique MATLAB program has been proposed for simulation of cutter contact points in the trajectory. The author has gone through C0 continuity concept and at last the simulated result has been shown by MATLAB program in its output. Keywords: Spline, Approximation technique, C++, IGES, MATLA
Accuracy of clinical coding for procedures in oral and maxillofacial surgery.
Clinical coding has important financial implications, and discrepancies in the assigned codes can directly affect the funding of a department and hospital. Over the last few years, numerous oversights have been noticed in the coding of oral and maxillofacial (OMF) procedures. To establish the accuracy and completeness of coding, we retrospectively analysed the records of patients during two time periods: March to May 2009 (324 patients), and January to March 2014 (200 patients). Two investigators independently collected and analysed the data to ensure accuracy and remove bias. A large proportion of operations were not assigned all the relevant codes, and only 32% - 33% were correct in both cycles. To our knowledge, this is the first reported audit of clinical coding in OMFS, and it highlights serious shortcomings that have substantial financial implications. Better input by the surgical team and improved communication between the surgical and coding departments will improve accuracy
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