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Kotta U.,Institute of Cybernetics
European Control Conference, ECC 1999 - Conference Proceedings | Year: 2015

The paper deals with nonlinear system described by the set of higher-order difference equations in the inputs and the outputs. A theorem for transforming such a system around a regular equilibrium point into a locally equivalent one, but having the so-called row- and column-reduced form, is formulated. The importance of this form comes from the fact that this is a suitable starting point for studing the realization problem for a set of nonlinear multi-input multi-output difference equations. © 1999 EUCA.

Di Marzo V.,CNR Institute of Biomolecular Chemistry | De Petrocellis L.,Institute of Cybernetics
Current Medicinal Chemistry | Year: 2010

In the late 1990's, a series of experiments carried out independently in two laboratories led to establish an important connection between the function of the endocannabinoids, which, as exemplified in this special issue, is per se very complex and ubiquitous in animals, and that of the transient receptor potential (TRP) channels, a large family of plasma membrane cation channels involved in several mammalian and non-mammalian physiological and pathological conditions, overlapping only in part with those in which the cannabinoid receptors participate. These experiments were initially based on the observation that the endocannabinoid anandamide and the xenobiotic ligand of TRP channels of V1 type (TRPV1), capsaicin, are somehow chemically similar, both compounds being fatty acid amides, as are also synthetic activators of these channels and inhibitors of anandamide cellular re-uptake. As discussed in this article, the same type of "chemical thoughts" led to the discovery of N-arachidonoyl-dopamine, an endogenous ligand of TRPV1 channels that behaves also an endocannabinoid. The overlap between the ligand recognition properties of some TRP channels and proteins of the endocannabinoid system, namely the cannabinoid receptors and the proteins and enzymes catalyzing anandamide cellular re-uptake and hydrolysis, is being actively explored through the rational design and synthesis of new endocan-nabinoid-based drugs with multiple mechanisms of action. These aspects are discussed in this review article, together with the possible functional and pharmacological consequences of endocannabinoid-TRP channel interactions. © 2010 Bentham Science Publishers Ltd.

Casagrande D.,University of Udine | Kotta U.,Institute of Cybernetics | Tonso M.,Institute of Cybernetics | Wyrwas M.,AGH University of Science and Technology
IEEE Transactions on Automatic Control | Year: 2010

Nonlinear control systems on homogeneous time scales are studied. First the concepts of reduction and irreducibility are extended to higher order delta-differential input-output equations. Subsequently, a definition of system equivalence is introduced which generalizes the notion of transfer equivalence in the linear case. Finally, the necessary and sufficient conditions are given for the existence of a state-space realization of a nonlinear input-output delta-differential equation. © 2006 IEEE.

Yefremov A.A.,Institute of Cybernetics
Proceedings of 2014 International Conference on Mechanical Engineering, Automation and Control Systems, MEACS 2014 | Year: 2014

This paper introduces new operations on fuzzy numbers and intervals. These operations allow keeping the shape of a membership function intact and constructing complex linguistic terms corresponding to such linguistic hedges as 'very' and 'more or less'. The article contains mathematical equations which allow us to determine the characteristic points of operation results for particular types of membership functions without integral evaluation. © 2014 IEEE.

Kakauridze G.,Institute of Cybernetics | Kilosanidze B.,Institute of Cybernetics
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2011

The new method of imaging Stokes spectropolarimetry in real time on the basis of polarization-holographic element is offered. Polarization-holographic element with complicated profile of anisotropy for the real-time complete analysis of polarization state of light (all Stokes parameters) is developed. During diffraction the element decomposes light incoming on them onto orthogonal circular and linear basis. The simultaneous measurement of the intensities in all points of images in diffracted orders by means of CCD matrices and appropriate software allows to determine the spatial distribution of a polarization state in the images of extended objects, and also the dispertion if this distribution. © 2011 Copyright SPIE - The International Society for Optical Engineering.

Didenkulova I.,Institute of Cybernetics | Didenkulova I.,Institute of Applied Physics | Pelinovsky E.,Institute of Applied Physics | Sergeeva A.,Institute of Applied Physics
Coastal Engineering | Year: 2011

The random long wave runup on a beach of constant slope is studied in the framework of the rigorous solutions of the nonlinear shallow water theory. These solutions are used for calculation of the statistical characteristics of the vertical displacement of the moving shoreline and its horizontal velocity. It is shown that probability characteristics of the runup heights and extreme values of the shoreline velocity coincide in the linear and nonlinear theory. If the incident wave is represented by a narrow-band Gaussian process, the runup height is described by a Rayleigh distribution. The significant runup height can also be found within the linear theory of long wave shoaling and runup. Wave nonlinearity nearshore does not affect the Gaussian probability distribution of the velocity of the moving shoreline. However the vertical displacement of the moving shoreline becomes non-Gaussian due to the wave nonlinearity. Its statistical moments are calculated analytically. It is shown that the mean water level increases (setup), the skewness is always positive and kurtosis is positive for weak amplitude waves and negative for strongly nonlinear waves. The probability of the wave breaking is also calculated and conditions of validity of the analytical theory are discussed. The spectral and statistical characteristics of the moving shoreline are studied in detail. It is shown that the probability of coastal floods grows with an increase in the nonlinearity. Randomness of the wave field nearshore leads to an increase in the wave spectrum width. © 2010 Elsevier B.V.

Gonzalez-Fernandez Y.,Institute of Cybernetics | Gonzalez-Fernandez Y.,York University | Soto M.,Institute of Cybernetics
Journal of Statistical Software | Year: 2014

The use of copula-based models in EDAs (estimation of distribution algorithms) is currently an active area of research. In this context, the copulaedas package for R provides a platform where EDAs based on copulas can be implemented and studied. The package offers complete implementations of various EDAs based on copulas and vines, a group of well-known optimization problems, and utility functions to study the performance of the algorithms. Newly developed EDAs can be easily integrated into the package by extending an S4 class with generic functions for their main components. This paper presents copulaedas by providing an overview of EDAs based on copulas, a description of the implementation of the package, and an illustration of its use through examples. The examples include running the EDAs defined in the package, implementing new algorithms, and performing an empirical study to compare the behavior of different algorithms on benchmark functions and a real-world problem. © 2014, American Statistical Association. All rights reserved.

Aliev T.A.,Institute of Cybernetics | Guluyev G.A.,Institute of Cybernetics | Pashayev F.H.,Institute of Cybernetics | Sadygov A.B.,Institute of Cybernetics
Mechanical Systems and Signal Processing | Year: 2012

Technology for determining values of noise variance, cross-correlation functions and coefficients of correlation between the useful signal and the noise is proposed for monitoring of the latent period of an object failure. The determined values form sets of informative attributes, which are equal to zero in the normal state of the object. In the course of object operation, values of elements that are different from zero are used to determine the moment and location of the fault. The technology has been applied in the monitoring system of the compressor unit at the Heydar Aliyev Baku Oil Refinery. © 2011 Elsevier Ltd. All rights reserved.

Didenkulova I.,Institute of Cybernetics | Didenkulova I.,Institute of Applied Physics | Pelinovsky E.,Institute of Applied Physics
Pure and Applied Geophysics | Year: 2011

The problem of tsunami wave shoaling and runup in U-shaped bays (such as fjords) and underwater canyons is studied in the framework of 1D shallow water theory with the use of an assumption of the uniform current on the cross-section. The wave shoaling in bays, when the depth varies smoothly along the channel axis, is studied with the use of asymptotic approach. In this case a weak reflection provides significant shoaling effects. The existence of traveling (progressive) waves, propagating in bays, when the water depth changes significantly along the channel axis, is studied within rigorous solutions of the shallow water theory. It is shown that traveling waves do exist for certain bay bathymetry configurations and may propagate over large distances without reflection. The tsunami runup in such bays is significantly larger than for a plane beach. © 2010 Springer Basel AG.

News Article | April 27, 2016
Site: www.nature.com

The 'small-n' challenge plagues all historians, but this problem of under-sized samples is especially acute in the history of science and technology. Most scientific discoveries seem to happen uniquely. We do sometimes see multiples — about half a dozen articulations of the principle of the conservation of energy or the periodic table around the same time, for example — but the diversity of specializations, the pace of communication and the vagaries of publishing mean that most innovations arise as singletons, to use sociologist Robert Merton's term. The issue is perhaps most striking with the flagship technology of our present moment: the Internet. Here, we have an n of 1. This matters for two reasons. First, singletons frustrate generalization, making it difficult to draw lessons for science policy. Second is the related puzzle of contingency. We currently have an Internet, and it has a set of properties (such as the end-to-end principle, which stipulates that applications should happen at the edges of the network, rather than at intermediary nodes). Does it look like this because it has to, or are its features contingent characteristics of this specific Internet? Without alternatives to compare it to — a larger n — we just cannot say. In How Not to Network a Nation, communications specialist Benjamin Peters argues for contingency, on the basis of an n increased from 1 to 2. Well, to 1.37 or thereabouts. Historians have already started to chronicle networks past as useful comparisons. One is Project Cybersyn, an experiment to network the Chilean economy under president Salvador Allende in the 1970s, described in Eden Medina's Cybernetic Revolutionaries (MIT Press, 2011). Peters summarizes these well, but his quarry is the great white whale of this specialized historiography: the Soviet Internet. Whether there ever was such a thing, why it never moved beyond the project stage and which of the various projects between the late 1950s and the late 1980s can be properly classified as efforts to develop one are the main subjects of the book. Peters makes a good case to move beyond historian Slava Gerovitch's excellent pun on this seeming oxymoron: “InterNyet”. His intuition is spot on. The cold-war origins of the US networking programme have been well documented, for example in Janet Abbate's Inventing the Internet (MIT Press, 1999). Direct military sponsorship was crucial. The defence department provided patronage through its Advanced Research Projects Agency, which launched ARPANET, the embryonic Internet, on 29 October 1969. The Internet's conceptual roots included cybernetics, created by mathematician Norbert Wiener in 1948. Given the close parallels between Soviet and US cold-war technologies, it would be surprising if there had been no efforts to generate a Soviet Internet. Indeed, Peters finds six different proposals to develop an 'all-union' computer network. This stands to reason, given what he calls “the outsized infrastructural imagination of Soviet planners”, who liked their projects big and utopian — think the space programme, dams and nuclear power. Peters concentrates on computer scientist Viktor Glushkov's OGAS (obshche-gosudarstvennaia avtomatizirovannaia sistema, as the standard Library of Congress transliteration would render it — although various systems are used inconstantly throughout the book). The full name is a mouthful: “All-State Automated System for the Gathering and Processing of Information for the Accounting, Planning, and Governance of the National Economy, USSR”. Beginning in 1962, Glushkov spent 25 years trying to mobilize support for his network from his Institute of Cybernetics in Kiev, which created a rich set of cultural resources, including a model constitution, passport and cartoons depicting the land of “Cybertonia”. Peters reproduces these in plentiful images and descriptions, chronicling their utopian spirit and demonstrating the need for engineers in all times to let off steam through flights of fancy. But the project was never realized. It is difficult to glean all the technical specifics from the material that Peters mobilizes from archives, interviews and declassified CIA reports. Some proposals look like cloud computing or tablets, but it would be anachronistic to interpret them in that way (and Peters doesn't). The idea was to use real-time processing to connect economic inputs and outputs, rendering the planned economy both functional and adaptive. We cannot even be sure that Glushkov's plans would have worked. What we do know is that the failure was not caused by a scarcity of personal computers, because OGAS was meant to link factory mainframes. Nor was it ideology: cybernetics, as Peters readably recounts, was well suited to Soviet ideological preferences in materialism and planning. To discover the roots of the issue, Peters invokes the cybernetic concept of heterarchy, which he defines as “complex networks with multiple conflicting regimes of evaluation in operation at the same time”; he then uses this to explore the heterogeneity of approaches to networking. Perhaps predictably, OGAS's demise was death by a thousand paper cuts. Documents were misfiled, meetings were missed, the military and the statistical ministries disagreed about who would benefit. Peters's provocative thesis is that “The capitalists behaved like socialists while the socialists behaved like capitalists.” The US Internet was the result of state subsidies and benevolent paternalism; the Soviet attempt foundered on entrepreneurial infighting. (Elsewhere, Peters puts the culprit down as cost, although how costs were tabulated was in itself a bureaucratic conundrum.) There is no dramatic climax to How Not to Network a Nation. Non-existent technologies end with a whimper, but even whimpers can tell you something.

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