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Boiling heat transfer in micro-channels is a subject of intense academic and practical interest. Though many heat transfer correlations have been proposed, most were empirically formulated from experimental data. However, hydrodynamic and thermal aspects of boiling in micro-channels are not well understood. Moreover, there are only a few theoretical models that link the heat transfer mechanism with...
Measures of divergence between two points play a key role in many engineering problems. One such measure is a distance function, but there are many important measures which do not satisfy the properties of the distance. The Bregman divergence, Kullback-Leibler divergence and f-divergence are such measures. In the present article, we study the differential-geometrical structure of a manifold induced...
Basic features of narrow optical beam interactions with a dielectric interface are analysed. As it was recently shown, two types of paraxial beams – elegant Hermite-Gaussians of linear polarization and elegant Laguerre-Gaussians of circular polarization – can be treated as vector normal modes of the interface [1]. In this contribution the problem of normal modes is discussed with special attention...
A problem of the Boussinesq type for flow of incompressible fluid through a medium with the porosity being a given function of time is studied. At first, from the continuity equation the Dupuit relation for the fluid velocity in the considered medium is found. Next the Boussinesq equation is derived for the medium. This equation, if written for quantity H = h/ and not for the hydraulic head h, has...
This paper introduces a new classifier design method based on regularized iteratively reweighted least squares criterion function. The proposed method uses various approximations of misclassification error, including: linear, sigmoidal, Huber and logarithmic. Using the represented theorem a kernel version of classifier design method is introduced. The conjugate gradient algorithm is used to minimize...
In optimization power theory we can distinguish the three approaches: -the theory of instant power values -the theory of average power values (integral power) -the theory of instant.average power value. The theory of instant power uses the instant power and signals values i.e. p(t) = u(t)i(t) whereas the theory of average power uses the energy or average power terms i.e. P = (u(t), i(t)) (the dot...
The unique characteristic of a repetitive processes is a series of sweeps, termed passes, through a set of dynamics defined over a finite duration. On each pass an output, termed the pass profile is produced which acts as on forcing function, and hence contributes to, the dynamics of the next pass profile. This leads to the possibility that the output, i.e. the sequence of pass profiles, will contain...
The discrete-time adaptive LQG control of first-order systems is considered from robustness point of view. Both stability and performance robustness are analyzed for different control system structures. A case of amplitude-constrained control is presented, and application of certainty equivalence for self-tuning implementation is also discussed.
In the paper, using some MATLAB fuzzy logic toolbox Demos, in which the fuzzy controllers are compared with the classical PID ones, it is shown that the well tuned classical PID controllers are significantly better than those fuzzy presented in the Demos. It is shown, that using fuzzy approach, it is very difficult to shape the input-output nonlinearity, describing the so called fuzzy block of the...
Two different analytical methods of determining extremal dynamic errors in linear dynamic systems are presented. The main idea of these methods is based on finding certain additional equations. These additional equations are obtained due to the assumption that an extremal point obtained from the necessary condition dx/dt=0, is also an extremum point with respect to initial conditions, that is, d/dci=...
The paper deals with the problem of surface-integral representation of electromagnetic force/torque for magnetically anisotropic region. It is pointed out that in some anisotropic regions a component of electromagnetic force/torque appears - the so-called anisotropy component. The total electromagnetic field force/torque calculated with the help of Maxwell’s and Lorentz’s methods could lead to the...
We present the basic high-level structures used for developing quantum programming languages. The presented structures are commonly used in many existing quantum programming languages and we use quantum pseudo-code based on QCL quantum programming language to describe them. We also present the implementation of introduced structures in GNU Octave language for scientific computing. Procedures used...
Tuning rules for position and velocity controllers in P-PI and PI-PI electrical servomechanisms are developed using the root locus design method. P-PI controller is equivalent to PID controller with a set-point filter. PI-PI servo provides zero steady-state error for linear disturbances, which may be important for some tracking tasks. Three design data are needed to calculate the tunings, i.e. drive...
Thermal and time delay aspects of long interconnect lines have been investigated. To design a modern integrated circuit we need to focus on very long global interconnects in order to achieve the desired frequency and signal synchronization. The long interconnection lines introduce significant time delays and heat generation in the driver transistors. Introducing buffers helps to spread the heat production...
In the present article we studied the thermodynamical theory of micropolar porous material and derived the equations of the linear theory of microploar porous generalized thermoelastic solid. Then the general solution to the field equations for plane axi-symmetric problem are obtained. The Laplace and Hankel transforms have been employed to study the problem, which are inverted numerically by using...
This paper briefly introduces side channel attacks on cryptographic hardware with special emphasis on differential power analysis (DPA). Based on existing countermeasures against DPA, design method combining power equalization for synchronous and combinatorial circuits has been proposed. AES algorithm has been implemented in Xilinx Spartan II-E field programmable gate array (FPGA) device using the...
The wheel-legged robot is a vehicle with many degrees of freedom. Thanks to its peculiar design, depending on the need, the vehicle will use one of its ways of moving: travelling on wheels or walking (in special situations), which enhances its locomotive properties. The paper presents the robot’s kinematic wheel suspension system, general operation strategy and control system. The application responsible...
The paper presents a localization system for a mobile robot using the vision system and LED markers and considers the problem of velocity and acceleration estimation in the case of planar motions. Theoretical considerations include the principle of measurement and the details of Kalman estimator with illustrations based on experimental setup. The presented measurement system can be used for a realization...
An approach to the problem of interoperability in open and heterogeneous multirobot system is presented. It is based on the paradigm of Service Oriented Architecture (SOA) and a generic representation of the environment. A robot, and generally a cognitive and intelligent device, is seen as a collection of its capabilities exposed as services. Several experimental protocols (for publishing, discovering,...
The paper deals with structuring robot control systems. The control system is decomposed into distinct agents. An agent, in general, is responsible for control of its effector, perception of the environment for the purpose of its effector control, and inter-agent communication. The behaviour of the agent is governed by its set of transition functions. The control system consists of two tiers – the...
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