scholarly journals INFORMATION PARAMETERS OF CODES THAT ARE SYNTHESIZED ON THE BASIS OF ONE MODULE

2020 ◽  
Vol 3 (7) ◽  
pp. 95-102
Author(s):  
Mikola Zaharchenko ◽  
Matin Hadzhyiev ◽  
Nariman Salmanov ◽  
Denis Golev ◽  
Natalya Shvets
Keyword(s):  
Information Transfer ◽  
Communication Channel ◽  
High Accuracy ◽  
Code Word ◽  
Russian Text ◽  
Constant Length ◽  
Efficient Coding ◽  
Digital Methods ◽  
Constant Duration

The advantages of digital methods of processing, displaying, storing and transmitting information. Currently, various conversion methods and efficient coding methods are used to increase the speed of information transfer, maintain high accuracy and provide the required latent accuracy. In particular, timer (temporary) signal constructions, which, in comparison with other coding methods, for example, positional (bitwise) coding, can reduce costs by more than two times. In the work, the information parameters of the code ensembles synthesized at a constant duration "m" are evaluated. Determined the conditions for the formation of a code ensemble and calculate the number of code dictionary implementations on a segment of a nyquist elements.In order to use the communication channel efficiently, the proposed increase in the entropy of the transmitted ensemble is due to the use of code sets with different number of information segments and at a constant length of the code word. A significant increase in the weight of the synthesized ensemble ensured an increase in the value of the module А0 =19 integer times K є 8:18 .The maximum values of the module are calculated in which the greatest number of code words is synthesized: At: КА0 =13, Np=8; КА0 =14, Np=10 КА0 =15, Np=15; КА0 =17, Np=16 КА0 =18, Np=10; КА0 =19, Np=6 КА0 =20, Np=1 For these КА0 values, the entropy value is H=3.269, which is less than the entropy of the Russian text H=4.35. In accordance with code words that satisfy the conditions of the quality equation. The methods and algorithms of reliable reception of code words under the influence of interference in the channel used were analyzed.Studies and calculations have shown that the use of temporary signal structures synthesized on the basis of a onemodule can significantly reduce the value of entropy for the transmission of Russian text.

Ultimate resolution and information in electron microscopy

1991 ◽  
Vol 49 ◽  
pp. 496-497
Author(s):  
D. Van Dyck
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Transfer Function ◽  
Information Transfer ◽  
Communication Channel ◽  
Structural Information ◽  
Information Rate ◽  
Noise Power ◽  
Signal Power ◽  
Imaging Device

An (electron) microscope can be considered as a communication channel that transfers structural information between an object and an observer. In electron microscopy this information is carried by electrons. According to the theory of Shannon the maximal information rate (or capacity) of a communication channel is given by C = B log2 (1 + S/N) bits/sec., where B is the band width, and S and N the average signal power, respectively noise power at the output. We will now apply to study the information transfer in an electron microscope. For simplicity we will assume the object and the image to be onedimensional (the results can straightforwardly be generalized). An imaging device can be characterized by its transfer function, which describes the magnitude with which a spatial frequency g is transferred through the device, n is the noise. Usually, the resolution of the instrument ᑭ is defined from the cut-off 1/ᑭ beyond which no spadal information is transferred.

Capacity of a Single Spiking Neuron Channel

2009 ◽  
Vol 21 (6) ◽  
pp. 1714-1748 ◽  
Author(s):  
Shiro Ikeda ◽  
Jonathan H. Manton
Keyword(s):  
Information Processing ◽  
Channel Capacity ◽  
Information Transfer ◽  
Communication Channel ◽  
Discrete Distribution ◽  
Random Variable ◽  
Temporal Coding ◽  
Reasonable Assumption ◽  
Rate Coding ◽  
The Brain

Information transfer through a single neuron is a fundamental component of information processing in the brain, and computing the information channel capacity is important to understand this information processing. The problem is difficult since the capacity depends on coding, characteristics of the communication channel, and optimization over input distributions, among other issues. In this letter, we consider two models. The temporal coding model of a neuron as a communication channel assumes the output is τ where τ is a gamma-distributed random variable corresponding to the interspike interval, that is, the time it takes for the neuron to fire once. The rate coding model is similar; the output is the actual rate of firing over a fixed period of time. Theoretical studies prove that the distribution of inputs, which achieves channel capacity, is a discrete distribution with finite mass points for temporal and rate coding under a reasonable assumption. This allows us to compute numerically the capacity of a neuron. Numerical results are in a plausible range based on biological evidence to date.

scholarly journals A Hybrid Speller Design Using Eye Tracking and SSVEP Brain–Computer Interface

Sensors ◽  
2020 ◽  
Vol 20 (3) ◽  
pp. 891 ◽  
Author(s):  
Malik M. Naeem Mannan ◽  
M. Ahmad Kamran ◽  
Shinil Kang ◽  
Hak Soo Choi ◽  
Myung Yung Jeong
Keyword(s):  
Eye Tracking ◽  
Classification Accuracy ◽  
Information Transfer ◽  
High Speed ◽  
Communication Channel ◽  
Computer Interface ◽  
Stimuli Responsive ◽  
Transfer Rates ◽  
Computer Interfaces ◽  
Large Numbers

Steady-state visual evoked potentials (SSVEPs) have been extensively utilized to develop brain–computer interfaces (BCIs) due to the advantages of robustness, large number of commands, high classification accuracies, and information transfer rates (ITRs). However, the use of several simultaneous flickering stimuli often causes high levels of user discomfort, tiredness, annoyingness, and fatigue. Here we propose to design a stimuli-responsive hybrid speller by using electroencephalography (EEG) and video-based eye-tracking to increase user comfortability levels when presented with large numbers of simultaneously flickering stimuli. Interestingly, a canonical correlation analysis (CCA)-based framework was useful to identify target frequency with a 1 s duration of flickering signal. Our proposed BCI-speller uses only six frequencies to classify forty-eight targets, thus achieve greatly increased ITR, whereas basic SSVEP BCI-spellers use an equal number of frequencies to the number of targets. Using this speller, we obtained an average classification accuracy of 90.35 ± 3.597% with an average ITR of 184.06 ± 12.761 bits per minute in a cued-spelling task and an ITR of 190.73 ± 17.849 bits per minute in a free-spelling task. Consequently, our proposed speller is superior to the other spellers in terms of targets classified, classification accuracy, and ITR, while producing less fatigue, annoyingness, tiredness and discomfort. Together, our proposed hybrid eye tracking and SSVEP BCI-based system will ultimately enable a truly high-speed communication channel.

Пассивные дальномеры: от оптических к оптико-­электронным системам

2020 ◽  
Vol 14 (4) ◽  
pp. 344-358
Author(s):  
А.В. Медведев ◽  
А.В. Гринкевич ◽  
С.Н. Князева
Keyword(s):  
High Accuracy ◽  
Range Measurements ◽  
Digital Methods

Пассивные оптические дальномеры обладают скрытностью, но не обеспечивают высокой точности измерения дальности в сравнении с лазерными дальномерами. Предложены новые оптические решения на основе комбинации цифровых методов и оригинальных оптических решений. Комбинация обеспечивает разнообразные варианты малогабаритных пассивных прицелов-­дальномеров с высокой точностью измерения дальности до цели при скрытности измерений. Passive optical rangefinders provide stealth, but do not provide high accuracy range measurements in comparison with laser ones. New optical solutions based on a combination of digital methods and original optical solutions are proposed. The combination provides a variety of options for small-­sized passive sights-­rangefinders with high accuracy of measuring the distance to the target with secretive measurements.

Computer Modeling of Underwater Communication Channel

2018 ◽  
Vol 1 (1) ◽  
Author(s):  
Alexander Andonov ◽  
◽  
◽  
Keyword(s):  
Information Transfer ◽  
Communication Channel ◽  
Underwater Communication ◽  
Output Data ◽  
Spreading Factor ◽  
Input And Output ◽  
Wide Range ◽  
Basic Parameters ◽  
Data Files ◽  
Improved Model

On the basis of the latest developments, an improved model of underwater communication channel is presented. A set of programs to allow calculation of the basic parameters of the channel over a wide range of parameters has been created. Mathematical models for calculating the spreading factor are developed. A process of creating the model is reviewed, so that the resulting model should become easily expandable. Userfriendly information-transfer interface is set between the programs and input and output data files.

scholarly journals Efficient population coding depends on stimulus convergence and source of noise

2021 ◽  
Vol 17 (4) ◽  
pp. e1008897
Author(s):  
Kai Röth ◽  
Shuai Shao ◽  
Julijana Gjorgjieva
Keyword(s):  
Information Transfer ◽  
Single Channel ◽  
Nerve Fibers ◽  
Optimal Number ◽  
Population Coding ◽  
Maximum Information ◽  
Sensory Stimuli ◽  
Efficient Coding ◽  
Theoretical Predictions ◽  
Optimal Information

Sensory organs transmit information to downstream brain circuits using a neural code comprised of spikes from multiple neurons. According to the prominent efficient coding framework, the properties of sensory populations have evolved to encode maximum information about stimuli given biophysical constraints. How information coding depends on the way sensory signals from multiple channels converge downstream is still unknown, especially in the presence of noise which corrupts the signal at different points along the pathway. Here, we calculated the optimal information transfer of a population of nonlinear neurons under two scenarios. First, a lumped-coding channel where the information from different inputs converges to a single channel, thus reducing the number of neurons. Second, an independent-coding channel when different inputs contribute independent information without convergence. In each case, we investigated information loss when the sensory signal was corrupted by two sources of noise. We determined critical noise levels at which the optimal number of distinct thresholds of individual neurons in the population changes. Comparing our system to classical physical systems, these changes correspond to first- or second-order phase transitions for the lumped- or the independent-coding channel, respectively. We relate our theoretical predictions to coding in a population of auditory nerve fibers recorded experimentally, and find signatures of efficient coding. Our results yield important insights into the diverse coding strategies used by neural populations to optimally integrate sensory stimuli in the presence of distinct sources of noise.

scholarly journals Communication space in the library and information sphere

2019 ◽  
pp. 31-41
Author(s):  
O. A. Solopova
Keyword(s):  
Information Transfer ◽  
Communication Channel ◽  
Communication Channels ◽  
Channel Selection ◽  
Communication Barriers ◽  
Target Audience ◽  
Communication Process ◽  
Negative Consequences ◽  
Selection Algorithm ◽  
Communication Space

Specific features of the communication space in the library and information sphere are discussed. The communication process players and factors are named. The communication space scheme for the library and information sphere is proposed. The scheme comprises: library and information staff, target audience (users), partners, and regulatory authorities. The formal and informal communication channels are characterized and compared with their advantages and drawbacks named. Several procedures for choosing communication channels relevant to target audience are proposed to increase effectiveness of the communication process and validity of communicant-recipient information transfer. Optimum communication channel selection stages and factors are characterized. Communication barriers due to wrong communication channel and their negative consequences for the communication process are described. Knowledge of the communication space in the library and information sphere and communication channel selection algorithm enables to exclude the communication barriers.

scholarly journals Performance Analysis With Different Types of Visual Stimuli in a BCI-Based Speller Under an RSVP Paradigm

2021 ◽  
Vol 14 ◽  
Author(s):  
Ricardo Ron-Angevin ◽  
M. Teresa Medina-Juliá ◽  
Álvaro Fernández-Rodríguez ◽  
Francisco Velasco-Álvarez ◽  
Jean-Marc Andre ◽  
...  
Keyword(s):  
Information Transfer ◽  
Communication Channel ◽  
Brain Computer Interface ◽  
Visual Presentation ◽  
Computer Interface ◽  
Ocular Motor ◽  
Alternative Communication ◽  
Information Transfer Rate ◽  
Different Types ◽  
Disabled Patients

Brain-Computer Interface (BCI) systems enable an alternative communication channel for severely-motor disabled patients to interact with their environment using no muscular movements. In recent years, the importance of research into non-gaze dependent brain-computer interface paradigms has been increasing, in contrast to the most frequently studied BCI-based speller paradigm (i.e., row-column presentation, RCP). Several visual modifications that have already been validated under the RCP paradigm for communication purposes have not been validated under the most extended non-gaze dependent rapid serial visual presentation (RSVP) paradigm. Thus, in the present study, three different sets of stimuli were assessed under RSVP, with the following communication features: white letters (WL), famous faces (FF), neutral pictures (NP). Eleven healthy subjects participated in this experiment, in which the subjects had to go through a calibration phase, an online phase and, finally, a subjective questionnaire completion phase. The results showed that the FF and NP stimuli promoted better performance in the calibration and online phases, being slightly better in the FF paradigm. Regarding the subjective questionnaires, again both FF and NP were preferred by the participants in contrast to the WL stimuli, but this time the NP stimuli scored slightly higher. These findings suggest that the use of FF and NP for RSVP-based spellers could be beneficial to increase information transfer rate in comparison to the most frequently used letter-based stimuli and could represent a promising communication system for individuals with altered ocular-motor function.

scholarly journals DETERMINATION OF PROBABILITY - TEMPORARY CHARACTERISTICS OF COMMUNICATION CHANNELS WHEN TRANSMITTING PRIORITY AND NON-PRIORITY DATA.

2019 ◽  
Vol 2019 (3) ◽  
pp. 20-27
Author(s):  
Sh Karimov ◽  
Keyword(s):  
Computer Networks ◽  
Petri Net ◽  
Information Transfer ◽  
Communication Channel ◽  
Stationary Mode ◽  
Input Stream ◽  
Distinctive Features ◽  
Basic Parameters

The article discusses the issues of finding the main indicators of the quality of the communication channel in computer networks when transmitting priority and non-priority data at different frame lengths. To solve this problem, methods of the theory of queuing using Petri nets are proposed. The proposed method for calculating the temporal and probabilistic characteristics of computer networks allows determinining the main indicators of the quality of the channel in a stationary mode when transmitting priority and non-priority data of computing tools at various values of the input stream intensity. To simulate the transmission of priority and non-priority frames, a color temporary Petri net is proposed. An algorithm is proposed for determining the basic parameters of information transfer, based on the use of the Little formula and allowing one to determine the number of frames in a queue, the average time a frame has been in a queue, and other distinctive features of the algorithm include the use of the window mode. The proposed technique allows to reduce the loss of priority frames of trajectory information and ensuring their transmission in real time.

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