Lossless Compression of High-frequency Intervals in Digital Audio : bachelor's thesisIvan Benc
, 2022, undergraduate thesis
Abstract: In this Thesis, an algorithm for lossless audio compression in a time domain is developed and implemented. The algorithm is designed to estimate the signal frequency based on the number of local extremes, and adapts the encoding to the estimated high or low- frequency intervals. As possible adaptations, fitting line segments, quadratic Bézier curves to the signal, and dictionary compression are examined. Residuals are encoded with delta encoding and compressed with binary adaptive sequential coding. The difference in the proportions of line segments and curves used in the high and low-frequency intervals have been detected, but this is not significant enough for this kind of interval discrimination to be meaningful in the current design of the algorithm.
Keywords: lossless audio compression, delta encoding, binary adaptive sequential coding, greedy method
Published in DKUM: 07.11.2022; Views: 133; Downloads: 23
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Software based encoder/decoder generation for data exchange optimization in the internet of things : master's thesisTjaž Vračko
, 2022, master's thesis
Abstract: Efficient encoding of data is an important part of projects in
the Internet of Things space. Communication packets must be kept
as small as possible in order to minimize the power consumption of
In this thesis, an automatic code generation tool, irpack, is proposed
that will unify the way packets are defined across all future
projects at Institute IRNAS.
Using a schema, this tool generates source code of encoders and
decoders in target programming languages. A schema evolution system
is also defined, by which changes to packets can be compatible
across multiple versions.
The tool is then applied to a selection of past projects to gauge
its usefulness. It is determined that irpack is able to encode the same
data into a similar or smaller size packet, while also providing
additional versioning information.
Keywords: encoding/decoding, schema, schema evolution, bit packing, code generation
Published in DKUM: 31.01.2022; Views: 365; Downloads: 53
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Modeling of molecular and cellular mechanisms involved in [Ca sup 2+] signal encoding in airway myocytesMarko Marhl
, Denis Noble
, Etienne Roux
, 2006, review article
Abstract: In airway myocytes signal transduction via cytosolic calcium plays an important role. In relation with experimental results we review models of basic molecular and cellular mechanisms involved in the signal transduction from the myocyte stimulation to the activation of the contractile apparatus. We concentrate on mechanisms for encoding of input signals into Ca2+ signals and the mechanisms for their decoding. The mechanisms are arranged into a general scheme of cellular signaling, the so-called bow-tie architecture of signaling, in which calcium plays the role of a common media for cellular signals and links the encoding and decoding part. The encoding of calcium signals in airway myocytes is better known and is presented in more detail. Inparticular, we focus on three recent models taking into account the intracellular calcium handling and ion fluxes through the plasma membrane. Themodel of membrane conductances was originally proposed for predicting membrane depolarization and voltage-dependent Ca2+ influx triggered by initialcytosolic Ca2+ increase as observed on cholinergic stimulation. Cellular models of intracellular Ca2+ handling were developed to investigate the role of a mixed population of InsP3 receptor isoforms and the cellular environment in the occurrence of Ca2+ oscillations, and the respective role ofthe sarcoplasmic reticulum, mitochondria, and cytosolic Ca2+-binding proteins in cytosolic Ca2+ clearance. Modeling the mechanisms responsible for the decoding of calcium signals is developed in a lesser extent; however, the most recent theoretical studies are briefly presented in relation with the known experimental results.
Keywords: biophysics, mathematical modelling, modelling, calcium oscillations, contractions, airway smooth muscle cells, muscle cells, smooth muscles, encoding, decoding, bow-tie structures
Published in DKUM: 07.06.2012; Views: 1671; Downloads: 39
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