scholarly journals Research on Speech Codec with Compression using Legendre Polynomials

2019 ◽  
Vol 8 (5S3) ◽  
pp. 278-284
Keyword(s):  
Harmonic Oscillator ◽  
Spherical Harmonic ◽  
Legendre Polynomials ◽  
Direct Method ◽  
Matrix Inversion ◽  
Timing Constraints ◽  
Filter Model ◽  
The Past ◽  
Speech Codec ◽  
Digital Telephony

Speech Codecs have been developed in several forms over the past 30 years and are used in Cellular digital telephony. Based on the throat excitation pulses and mouth cavity filter model, all the methods aim to encode the speech samples without much loss of clarity. The complexity of the methods using codebook searching, filtering and matrix inversion, all need heavy computations, leading to timing constraints. After describing a tutorial elucidating the essentials of the present methods, a different direct method of encoding, suggested by the spherical harmonic oscillator functions of Legendre, is introduced. Its performance and simplicity are such that the same may find its applications soon.

scholarly journals First in situ record of decadal glacier mass balance (2003–2014) from the Bhutan Himalaya

2016 ◽  
Vol 57 (71) ◽  
pp. 289-294 ◽  
Author(s):  
Phuntsho Tshering ◽  
Koji Fujita
Keyword(s):  
Mass Balance ◽  
Direct Method ◽  
Eastern Himalaya ◽  
Glacier Mass Balance ◽  
Differential Gps ◽  
Humid Climate ◽  
Equilibrium Line Altitude ◽  
The Past ◽  
Southeastern Tibet

AbstractThis study presents the first decadal mass-balance record of a small debris-free glacier in the Bhutan Himalaya, where few in situ measurements have been reported to date. Since 2003 we have measured the mass balance of Gangju La glacier, which covers an area of 0.3km2 and extends from 4900 to 5200ma.s.l., using both differential GPS surveys (geodetic method) and stake measurements (direct method). The observed mass balance ranged from –1.12 to –2.04mw.e. a–1 between 2003 and 2014. The glacier exhibited much greater mass loss than neighbouring glaciers in the eastern Himalaya and southeastern Tibet, which are expected to be sensitive to climate change due to the monsooninfluenced humid climate. Observed mass-balance profiles suggest that the equilibrium-line altitude has been higher than Gangju La glacier since 2003, implying that the entire glacier has experienced net ablation for at least the past decade.

scholarly journals Exact solution of a kind of n-dimensions non-spherical harmonic oscillator p otential

2003 ◽  
Vol 52 (8) ◽  
pp. 1858
Author(s):  
Long Chao-Yun ◽  
Chen Ming-Lun ◽  
Cai Shao-Hong
Keyword(s):  
Exact Solution ◽  
Harmonic Oscillator ◽  
Spherical Harmonic

WKB quantization rules for three-dimensional confinement

2001 ◽  
Vol 79 (6) ◽  
pp. 939-946 ◽  
Author(s):  
A Sinha ◽  
R Roychoudhury ◽  
Y P Varshni
Keyword(s):  
Hydrogen Atom ◽  
Harmonic Oscillator ◽  
Reasonable Agreement ◽  
Three Dimensional ◽  
Quantum Systems ◽  
The Past ◽  
Two Systems ◽  
Mathematical Techniques ◽  
Confined Quantum Systems ◽  
Quantization Rules

Confined quantum systems have been studied by various authors over the past decades, by using various mathematical techniques. In this work, we derive the WKB quantization rules for quantum systems confined in an impenetrable spherical box of radius r0. We apply the proposed method to two systems explicitly, viz., the confined harmonic oscillator and the confined hydrogen atom. The results are found to be in reasonable agreement with those obtained by other methods. PACS No.: 03.65

Embarrassingly Parallel GPU Based Matrix Inversion Algorithm for Big Climate Data Assimilation

2018 ◽  
Vol 10 (1) ◽  
pp. 71-92 ◽  
Author(s):  
M. Varalakshmi ◽  
Amit Parashuram Kesarkar ◽  
Daphne Lopez
Keyword(s):  
Data Assimilation ◽  
Direct Method ◽  
Weather Prediction ◽  
Matrix Inversion ◽  
Climate Data ◽  
Inversion Algorithm ◽  
Test Environment ◽  
Multiple Gpus ◽  
Resolution Model ◽  
Speed Up

Attempts to harness the big climate data that come from high-resolution model output and advanced sensors to provide more accurate and rapidly-updated weather prediction, call for innovations in the existing data assimilation systems. Matrix inversion is a key operation in a majority of data assimilation techniques. Hence, this article presents out-of-core CUDA implementation of an iterative method of matrix inversion. The results show significant speed up for even square matrices of size 1024 X 1024 and more, without sacrificing the accuracy of the results. In a similar test environment, the comparison of this approach with a direct method such as the Gauss-Jordan approach, modified to process large matrices that cannot be processed directly within a single kernel call shows that the former is twice as efficient as the latter. This acceleration is attributed to the division-free design and the embarrassingly parallel nature of every sub-task of the algorithm. The parallel algorithm has been designed to be highly scalable when implemented with multiple GPUs for handling large matrices.

Sign in / Sign up

Export Citation Format

Share Document