573 research outputs found
A REVIEW ON MULTIPLE-FEATURE-BASED ADAPTIVE SPARSE REPRESENTATION (MFASR) AND OTHER CLASSIFICATION TYPES
A new technique Multiple-feature-based adaptive sparse representation (MFASR) has been demonstrated for Hyperspectral Images (HSI's) classification. This method involves mainly in four steps at the various stages. The spectral and spatial information reflected from the original Hyperspectral Images with four various features. A shape adaptive (SA) spatial region is obtained in each pixel region at the second step. The algorithm namely sparse representation has applied to get the coefficients of sparse for each shape adaptive region in the form of matrix with multiple features. For each test pixel, the class label is determined with the help of obtained coefficients. The performances of MFASR have much better classification results than other classifiers in the terms of quantitative and qualitative percentage of results. This MFASR will make benefit of strong correlations that are obtained from different extracted features and this make use of effective features and effective adaptive sparse representation. Thus, the very high classification performance was achieved through this MFASR technique
A Report on the Preliminary design of Composite Cocured LCA Fin
A report on the preliminary design of composite cocured LCA fin is presented. A six spar structural configuration involving laminated carbon composite construction is employed in the design of torsion box. The design studies are carried out using a strength of materials based analysis. Three critical loading cases have been considered in the investigation. Results for various cases studied are presented and discussed
MR Spectroscopic Imaging of Peripheral Zone in Prostate Cancer Using a 3T MRI Scanner: Endorectal versus External Phased Array Coils.
Magnetic resonance spectroscopic imaging (MRSI) detects alterations in major prostate metabolites, such as citrate (Cit), creatine (Cr), and choline (Ch). We evaluated the sensitivity and accuracy of three-dimensional MRSI of prostate using an endorectal compared to an external phased array "receive" coil on a 3T MRI scanner. Eighteen patients with prostate cancer (PCa) who underwent endorectal MR imaging and proton (1H) MRSI were included in this study. Immediately after the endorectal MRSI scan, the PCa patients were scanned with the external phased array coil. The endorectal coil-detected metabolite ratio [(Ch+Cr)/Cit] was significantly higher in cancer locations (1.667 ± 0.663) compared to non-cancer locations (0.978 ± 0.420) (P < 0.001). Similarly, for the external phased array, the ratio was significantly higher in cancer locations (1.070 ± 0.525) compared to non-cancer locations (0.521 ± 0.310) (P < 0.001). The sensitivity and accuracy of cancer detection were 81% and 78% using the endorectal 'receive' coil, and 69% and 75%, respectively using the external phased array 'receive' coil
Epidemiology of Helicobacter pylori infection in dyspeptic Ghanaian patients
Introduction: Helicobacter pylori is a gram-negative urease-producing bacterium causally linked with gastritis, peptic ulcer disease and gastricadenocarcinoma. Infection is more frequent and acquired at an earlier age in developing countries compared to European populations. The incidence of Helicobacter pylori infection in dyspeptic Ghanaian patients was 75.4 %. However, epidemiological factors associated with infection vary across populations. Methods: This study used a cross-sectional design to consecutively sample dyspeptic patients at the Endoscopy Unit of the Korle-Bu Teaching Hospital, Accra between 2010 and 2012. The study questionnaire elicited their epidemiological clinical characteristics. Helicobacter pylori infection was confirmed by rapid-urease examination of antral biopsies at upper Gastro-intestinal endoscopy.Results: The sample population of dyspeptic patients attending the Endoscopy Unit for upper GI endoscopy yielded 242 patients of which 47.5 % were females. The age distribution of H. pylori-infection was even across most age – groups, ranging from 69.2% (61 – 70) years to 80% (21 –30) years. Helicobacter pylori prevalence decreased across areas mapping to the three residential classes in accordance with increasing affluence with rural areas having the highest prevalence. The unemployed and patients in farming had relatively high Helicobacter pylori infection rates of 92.3 % and 91.7 % respectively.Conclusion: Helicobacter pylori is endemic in Ghana but the persistently high prevalence across age groups despite significant community anti-microbial use suggests likely re-crudescence or re-infection from multiple sources in a developing country. Socio-cultural factors such as residential class and farming may be facilitating factors for its continued prevalence
Simulation of the Performance of the IISc Chemical Kinetics Shock Tube
This report presents the results of an investigation of the performance of the Chemical Kinetics Shock tube at the Indian Institute of Science. The one-dimensional Lagrangian code L1d of Jacobs (1998) has been used to simulate the tube at several operating conditions. The conditions have different shock tube filling pressures, resulting in different shock speeds and different tube lengths, resulting in different dwell times. The simulations have been performed both with and without viscous effects simulated in the tubes. At the lowest shock tube filling pressure condition, the shock tube operates in an overtailored mode and it is undertailored at the higher filling pressure conditions. The results show that viscous effects, which lead to attenuation of the primary shock and heat loss from the test gas to the tube walls, result in an increasing p5 pressure during the test time. The viscous effects are more dominant at the condition with the lowest filling pressure (highest primary shock speed). A simulation run for 50 ms after diaphragm rupture or the configuration with a long driver tube shows that the test gas is periodically re-compressed by reflections of waves along the driver and shock tubes. The recompressions become sequentially weaker and thus the test gas temperature and pressure are never raised to as high levels as for the primary compression
An energy-efficient cluster head selection in wireless sensor network using grey wolf optimization algorithm
Clustering is considered as one of the most prominent solutions to preserve theenergy in the wireless sensor networks. However, for optimal clustering, anenergy efficient cluster head selection is quite important. Improper selectionofcluster heads(CHs) consumes high energy compared to other sensor nodesdue to the transmission of data packets between the cluster members and thesink node. Thereby, it reduces the network lifetime and performance of thenetwork. In order to overcome the issues, we propose a novelcluster headselection approach usinggrey wolf optimization algorithm(GWO) namelyGWO-CH which considers the residual energy, intra-cluster and sink distance.In addition to that, we formulated an objective function and weight parametersfor anefficient cluster head selection and cluster formation. The proposedalgorithm is tested in different wireless sensor network scenarios by varyingthe number of sensor nodes and cluster heads. The observed results conveythat the proposed algorithm outperforms in terms of achieving better networkperformance compare to other algorithms
Microstructure and Mechanical properties of Borated Stainless Steel (304B) GTA and SMA welds
Borated stainless steels are used in nuclear power plants due to their high capacity to absorb thermal neutrons.Borated Stainless Steels are being used to control neutron criticality in reactors as control rods, shieldingmaterial, spent fuel storage racks and transportation casks. In the present study, an attempt has been madeto investigate the microstructural and mechanical properties of the borated stainless steel welds made on10 mm thick plates, using SMAW and GTAW welding processes. Microstructural investigations revealed thatthe fusion zone in GTAW exhibited dendritic structure with eutectic constituents in interdendritic regions. GTAwelds failed in the partially melted zones formed (PMZ) immediately adjacent to the fusion zone, while theSMA welds failed in the base metal because of the high heat input used per pass in GTAW process resulting inlarger PMZ. The heat input in GTAW was very high compared to the SMAW while both the welds exhibited highjoint efficiencies, SMA welds were found to be superior. Impact testing revealed that welds made using SMAexhibited significantly higher toughness as the filler does not contain boron. It has been concluded that highefficiency welded joints can be made on 304B plates using both the processes
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