3,354 research outputs found
Speech Enhancement using Adaptive Mean Median Deviation and EMD Technique
No full textDuring the acquisition of the speech signal by the non-contact Speech Sensor (SS), the signal is degraded by severe colored noises which are non-linear and non-uniform in nature. Therefore, in this study, a new approach for advancing the speech enhancement technique is proposed to suppress these noises from the acquired speech signal. This technique is based on the adaptive thresholding, which uses Mean Median Deviation (MMD) method to determine adaptive threshold points, and Empirical Mode Decomposition (EMD) method. This algorithm has been validated by simulation data, and results of the proposed algorithm have been compared with other existing enhancement algorithms. Spectrograms and Signal to Noise Ratio (SNR) comparison are used to analyze the quality of the enhanced speech signal. From the results, we demonstrate that the proposed algorithm offers better speech enhancement than previously existing speech enhancement techniques
PPGAppendix_ed - Glacier facies characterization using optical satellite data: Impacts of radiometric resolution, seasonality, and surface morphology
No full textPPGAppendix_ed for Glacier facies characterization using optical satellite data: Impacts of radiometric resolution, seasonality, and surface morphology by Bisma Yousuf, Aparna Shukla, Manoj Kumar Arora and Avtar Singh Jasrotia in Progress in Physical Geography: Earth and Environment</p
Photoluminescence properties of europium-activated double layered perovskite Sr 3 Ti 2 O 7 for high-quality lighting applications
No full textThermally stable double-layered perovskite materials for solid-state lighting applications.We present a comprehensive investigation into the concentration and temperature-dependent photoluminescence (PL) properties of europium ion (Eu 3+ ) activated double-layered perovskite Sr 3 Ti 2 O 7 materials. We conducted thorough analyses to assess their phase purity, crystal structure, surface morphology, and optical properties to gain a complete understanding. The double-layered perovskite Sr 3 Ti 2 O 7 :Eu 3+ exhibited a tetragonal phase with space group I 4/ mmm . When excited by 395 nm ultraviolet (UV) light, the prepared materials exhibited a firm red emission peak at 616 nm, indicating the hypersensitive electric dipole transition 5 D 0 → 7 F 2 in Eu 3+ ions. The quantum yield of the optimized sample was estimated to be 18%. To explore the temperature-dependent behavior of the photoluminescence, measurements were carried out over a wide range of temperatures from 300 K to 450 K. Notably, the phosphors demonstrated significant thermal stability, with 75% of the emission intensity retained at 420 K compared to 300 K. These findings signify the material's ability to maintain its luminescent properties at elevated temperatures. The photometric characterization of Sr 3 Ti 2 O 7 :Eu 3+ further validated its red emission capability. Moreover, we employed the Judd–Ofelt approach to examine the radiative intensity parameters ( Ω 2 , Ω 4 , Ω 6 ). The obtained results provide substantial support for the promising prospects of this perovskite material in the rapidly growing field of solid-state lighting and display devices.Thermally stable double-layered perovskite materials for solid-state lighting applications.We present a comprehensive investigation into the concentration and temperature-dependent photoluminescence (PL) properties of europium ion (Eu 3+ ) activated double-layered perovskite Sr 3 Ti 2 O 7 materials. We conducted thorough analyses to assess their phase purity, crystal structure, surface morphology, and optical properties to gain a complete understanding. The double-layered perovskite Sr 3 Ti 2 O 7 :Eu 3+ exhibited a tetragonal phase with space group I 4/ mmm . When excited by 395 nm ultraviolet (UV) light, the prepared materials exhibited a firm red emission peak at 616 nm, indicating the hypersensitive electric dipole transition 5 D 0 → 7 F 2 in Eu 3+ ions. The quantum yield of the optimized sample was estimated to be 18%. To explore the temperature-dependent behavior of the photoluminescence, measurements were carried out over a wide range of temperatures from 300 K to 450 K. Notably, the phosphors demonstrated significant thermal stability, with 75% of the emission intensity retained at 420 K compared to 300 K. These findings signify the material's ability to maintain its luminescent properties at elevated temperatures. The photometric characterization of Sr 3 Ti 2 O 7 :Eu 3+ further validated its red emission capability. Moreover, we employed the Judd–Ofelt approach to examine the radiative intensity parameters ( Ω 2 , Ω 4 , Ω 6 ). The obtained results provide substantial support for the promising prospects of this perovskite material in the rapidly growing field of solid-state lighting and display devices.Alexander von Humboldt-Stiftung https://doi.org/10.13039/10000515
#x03C3;LBDR: Congestion-aware logic based distributed routing for 2D NoC
No full textWith the advent of multi-core technologies, a significant amount of research has been directed towards running multiple applications concurrently and efficiently. This elevates work load on the network which leads to congestion and subsequently degrades the performance and increases the latency of the network. Table based methods can be used for handling congestion but these methods are not scalable in terms of area. In this paper, we propose a novel routing mechanism that eliminates the need of large routing tables. The results show the performance of σLBDR is better than competing routing algorithms for handling congestion as the area requirement is very less irrespective of the size of the network.</p
A novel non-minimal turn model for highly adaptive routing in 2D NoCs
No full textNetwork-on-Chip (NoC) is emerging as a promising communication paradigm to overcome bottleneck of traditional bus-based interconnects for future micro-architectures (MPSoC and CMP). One of current issue in NoC routing is the use of acyclic channel dependency graph (ACDG) for deadlock freedom prohibiting certain routing turns. Thus, ACDG reduces the degree of adaptiveness. In this paper, we propose a novel nonminimal turn model which allows cycles in channel dependency graph provided that extended channel dependency graph is acyclic. Proposed turn model reduces number of restrictions on routing turns (specially on 90-degree), hence able to provide additional minimal and non-minimal routes between source and destination. We also propose a non-minimal and congestion-aware adaptive routing algorithm based on proposed turn model to demonstrate advantages. From results, we can observe that proposed method improves the network performance by distributing the traffic load in the non-congested regions.</p
Fault tolerant and highly adaptive routing for 2D NoCs
No full textNetworks-on-Chip (NoCs) are emerging as a promising communication paradigm to overcome bottleneck of traditional bus-based interconnects for current microarchitectures (MCSoC and CMP). One of the known current problems in NoC routing is the use of acyclic Channel Dependency Graph (CDG) for deadlock freedom. This requirement forces certain routing turns to be prohibited, thus, reducing the degree of adaptiveness. In this paper, we propose a novel non-minimal turn model which allows cycles in CDG provided that Extended Channel Dependency Graph (ECDG) remains acyclic. The proposed turn model reduces number of restrictions on routing turns, hence able to provide path diversity through additional minimal and non-minimal routes between source and destination. We also develop a fault tolerant and congestion-aware routing algorithm based on the proposed turn model to demonstrate the effectiveness. In this algorithm, a non-minimal route is used only when links in minimal routes are congested or faulty. Average performance gain of the proposed method is up to 26% across all selected benchmarks when compared with DRFT and 12% when compared with LEAR for 7 × 7 mesh.</p
Network-on-chip: Current issues and challenges
No full textDue to the shrinking transistor sizes, the density of ICs roughly doubles every year as predicted by Moore's law. These advancements in the VLSI integration densities towards the nano scale era, witnessed a paradigm shift from computation centric designs to communication centric designs incorporating very large number of simple cores. Plenty of traditional interconnect schemes like point to point, buses and crossbars are available to interconnect small number of cores. While achieving fast and efficient communication with point to point communication schemes, wire density is a barrier for adapting them to many core architectures. Moreover, buses are simpler in design, they suffer from the scalability and arbitration issues along with bandwidth bottleneck as the number of cores increases. Similarly area and power requirements of a crossbar limits its applicability. Hence, in many core architectures like Chip Multiprocessors (CMP) and Multi processor System-on-Chip (MPSoCs), emerge the need of an efficient communication infrastructure as traditional solutions fails to handle the communication challenges. Network-on-Chip (NoC), a scalable and modular design approach, has been proposed as a promising alternative to traditional bus based architectures for inter-core communication
Monitoring of spatio‐temporal glaciers dynamics in Bhagirathi Basin, Gharhwal Himalayas using remote sensing data
No full textGlacier retreat represents a highly sensitive indicator of climate change and global warming. Therefore, timely mapping and monitoring of glacier dynamics is strategic for water budget forecasting and sustainable management of water resources. In this study, Landsat satellite images of 2000 and 2015 have been used to estimate area extent variations in 29 glaciers of the Bhagirathi basin, Garhwali Himalayas. ASTER DEM has been used for extraction of glacier terrain features, such as elevation, slope, area, etc. It is observed from the analysis that Bhagirathi sub-basin has a maximum glaciated area of ~ 35% and Pilang has the least with ~ 3.2%, whereas Kaldi sub-basin has no glacier. In this region, out of 29 glaciers, 25 glaciers have
shown retreat, while only 4 glaciers have shown advancement resulting in a total glacier area loss of ~ 0.5%, while the retreat rate varies from ~ 0.06 m/yr to ~ 19.4 m/yr. Dokarni glacier has maximum retreat rate (~ 19.4 m/yr), whereas Dehigad has maximum advancing rate (~ 10.1 m/yr). Glaciers retreat and advance have also been analyzed based on terrain parameters and observed that northern and southern orientations have shown retreat, whereas the area change is highly correlated with glacier length. The study covers more than 65% of the total glaciated area and based on the existing literature represents one of the most exhaustive studies to cover the highest number of glaciers in all sub-basins of the Bhagirathi basin
Improved adaptive routing for networks-on-chip
No full textThe degree of adaptiveness has a major impact on the performance of an adaptive routing method. An improved turn model-based routing method that provides a high degree of adaptiveness for a 2D mesh is presented. The proposed method reduces restrictions on the routing turns significantly and hence can provide path diversity using additional routes (both minimal and non-minimal). Experimental results show that the proposed method provides better performance (average latency and throughput) compared with recent routing methods
RECTIFIED DIFFERENTIAL CRYPTANALYSIS OF 16 ROUND PRESENT
No full textRECTIFIED DIFFERENTIAL CRYPTANALYSIS OF 16 ROUND PRESENT
Manoj Kumar , Pratibha Yadav and Meena Kumari
SAG, DRDO, Metcalfe House, Delhi-110054, India
ABSTRACT
In this paper, we have suggested rectifications in differential cryptanalysis of ultra-lightweight block cipher PRESENT reduced to 16 rounds. We have shown that proposed differential attack by Wang [3] on 16 round PRESENT can recover at the most 30 subkey bits, although the author has claimed to recover 32 bits of subkey for last two rounds. We have also computed data complexity and success probability for recovering 30 subkey bits accordingly by the differential attack on 16 round PRESENT.
KEYWORDS
Lightweight block cipher, differential cryptanalysis, PRESEN
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