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When optimizing the directivity and energy characteristics of the antennas with flat reflectors and the leaky-wave antennas, high-speed computational algorithms are required for a reliable analysis of the diffraction of electromagnetic waves on a conducting screen, accounting for the inhomogeneities with the dimensions commensurate with the wavelength. To calculate the diffraction field of an electromagnetic wave with an arbitrary-shaped front on a rectangular groove in the screen, a numerical model has been developed. This model is based on the approximation of the wave front by finite locally flat patches and the use of the authors' rigorous solution of the problem of locally flat wave diffraction on a conducting screen with a groove. The field above the screen is represented by the Fourier integral, while the field in the groove – by the sum of waveguide modes. The set of functional equations is obtained using the method of partial domains. Through a re-expansion of the modal functions of the field of partial domains in terms of the basis of the adjacent domain, the functional equations are reduced to a set of linear algebraic equations with respect to the complex amplitudes of the waveguide modes of the groove. The implementation of the main computational procedures is described. Based on the analysis of the particular results, the reliability of the developed model is proved. The influence of the quality of the wave front interpolation on the accuracy of the solution is studied. Recommendations on the frequency of a wave-front fragmentation are formulated. The proposed digital algorithm can be used to analyze and synthesize antennas with the flat perforated distributing and radiating systems. [ABSTRACT FROM AUTHOR]

The paper presents the results of data simulation for managing digital projects of information audit of enterprise processes. Based on the study of the main business processes of the enterprise, key indicators of the IT-audit are determined. The mathematical formulation of the task of conducting the IT-audit is presented. The system dynamics method is applied to model key indicators of IT-audit of business processes. [ABSTRACT FROM AUTHOR]

The competency to think critically is one of the skills that students must possess in the 21st century. This study aims to determine vocational students' critical thinking skills (CTs) in digital simulation and communication subjects using expository based on digital learning repository. This research uses quantitative descriptive. The samples of this study were students of class X SMK N 2 Surakarta. The instrument used is a multiple-choice test that developed based on indicators of CTs, according to Facione, which consist of interpretation, analysis, evaluation, inference, explanation, and self-regulation. The results of this study showed that the average percentage of students' CTs is in the sufficient category. The results of each indicator can be described as follows: (1) The interpretation indicator is 46.8% in the sufficient category, (2) The analysis indicator is 49.5% in the sufficient category, (3) The evaluation indicator is 60.5% in the sufficient category, (4) The inference indicator is 48, 4% in the sufficient category, (5) About 56.5% for the explanation indicator in the sufficient category, and (6) The self-regulation indicator is 64.5% in the high category. The results showed that students' CTs were still quite or moderate. Students' CTs need to be improved with innovative learning models and methods that will affect learning motivation and critical thinking skills towards various student problems in teaching and learning activities. [ABSTRACT FROM AUTHOR]

The introduction of new repair technologies requiring production readjustments is inextricably linked with the development of effective digital modeling methods. The paper presents some research results on the creation of a methodology for the automated design of technological processes for the production of car repair enterprises, based on digital modeling of car structures and technological processes of their repair. The article considers the method of constructing a mathematical model of the car (or its unit) structure, created on the basis of the structural-parametric method, which allows the most efficient way to carry out the exploding of the structure and the formation of the composition of sets of technological documentation for the repair of cars. The block diagram of the automatic coupler and the graph, which is a mathematical description of this structure, are given. [ABSTRACT FROM AUTHOR]

A digital eco-monitoring platform is considered as a control system for a complex multi-circuit object with a Von Neumann-type regulator. Common analytical models of object under control and data processing by digital controller are obtained. It is shown, that transfer functions, obtained from analytical description of discrete data processing by digital controller may be combined with transfer functions, obtained from analytical description of object under control reaction on continual actions. Typical flow-chart and analytical mathematical model of system functioning, which takes into account time delays between transactions, caused by sequential interpretation of control algorithm operators and random character of data processed, is worked out. It is shown, that time lags between transactions adduce to an appearance in transfer function both numerator and denominator of closed through digital controller system, complex exponents, which describes such phenomena as data skew, and pure lag. The method of time intervals between transactions estimation in cyclic algorithms of arbitrary complexity, based on their representation as semi-Markov process, is proposed. Theoretical postulates are confirmed by simulation of two-loop digital control system functioning. [ABSTRACT FROM AUTHOR]

This paper discusses Brushless DC Motor (BLDCM) drives using a resolver which is implemented in PSIM digital simulation software. In contrast to the use of a hall-effect sensor (HES) which can be used directly because the output is digital, the use of a resolver requires a resolver to digital converter (RTDC) algorithm to produce digital output such as HES which is used as the information for operating six-step commutation. Furthermore, the resolver can also be used as a speed detection through a calculation algorithm too. These algorithms are embedded through PSIM's simplified C-block feature. Based on the results of the tests that have been carried out, these resolver-based BLDCM drives produce reliable drive performance at variable speed, constant speed (high and low speed) operation, and under load conditions. The speed calculation results also produce precise and accurate characteristics. The resolver can be a reliable solution for BLDCM commutation and speed detection, so it can save on the use of sensors used. [ABSTRACT FROM AUTHOR]

The problem of the development of low-generation technologies is currently a topical problem. This article presents a study of the electric modes of a gas piston generator that combines electromagnetic transmission between a generator and a turbine instead of a mechanical coupling in order to increase the dynamic stability of a generator operating on an electrical network under various disturbing influences. The results of experimental studies are presented. Also, the construction of dynamic models of a gas piston plant in the RTDS system (real time digital simulation) and the results of various transients during a short circuit in the electrical network are considered. [ABSTRACT FROM AUTHOR]

The purpose of the study is to determine the impact of a groundbreaking technology on the development of production using a digital model of the enterprise, reflecting the current trend in the use of resources, and a significant increase in the intensity of use of production resources due to innovation introduction. The following research tasks are to be solved: influence assessment of a new technology in comparison with the previous one, taking into account the prevailing conditions of production process under consideration and determination of the role of previous statistics in the current intensification of the use of production resources. It was found that the predicted values of production volume are determined not by the sum of previous values of output and the new values of volume, but by the multiplication product of the previous volume by a special factor. It is shown that when using a groundbreaking technology, it is of particular interest to assess the multiple effects of production resources on production volume. The importance of this process was established at an integrated analysis of situations developing in production. An example of increase calculation in the production volume when introducing a groundbreaking technology is given. [ABSTRACT FROM AUTHOR]

The advantages and features of the use of simulation modeling in digital transformation projects of business processes are considered. The interrelation of business processes models with information technologies that automate the execution of business processes at enterprises in real time is shown. The aspects of planning experiments within the framework of a stochastic simulation model of a business process based on statistical modeling methods to obtain adequate simulation results are considered. The principles of constructing models of business processes are formulated and the possibilities that simulation modeling provides in the context of transforming business processes of an enterprise are revealed. [ABSTRACT FROM AUTHOR]

Bending rigidity of the textile materials determines the textile fabric handle and drape and affects the handling process during the assembly of the clothing. This paper gives overview about the state of the art in the literature regarding the testing of the bending rigidity, its influence from the pattern and material type and from the availability of sewing threads. After the review of the state of the art a preliminary experimental results of investigation the sewing lines and the type of the opening of the allowances are reported. The results demonstrate that the seams change the bending rigidity of the fabrics and these changes have to be considered during the drape simulation and digital fit of clothing. [ABSTRACT FROM AUTHOR]

The multiple-input single-output (MISO) technique is undoubtedly one of the most revolutionary perspectives adapted to the second generation's DVB-T2 terrestrial standard. Compared to Single-input single-output (SISO), it can minimize harmful interference and boost Single Frequency Network coverage. This paper represents a simulation of digital television signal transmission according to the DVB-T2 SFNs with MISO transmission mode employment. DVB-T2 MISO modified Alamouti mode is compared with the traditional SISO SFNs. Different types of propagation channel models were used: fixed, mobile reception of Gaussian, Ricean, and Rayleigh channels for both SISO, MISO SFNs simulation scenarios. MISO diversity gain and graphical bit error rate (BER) dependencies after LDPC encoding have been obtained. Finally, accomplished simulation results are evaluated and discussed with encouraging expectations of the MISO diversity scheme's outstanding performance in DVB-T2 SFNs areas. [ABSTRACT FROM AUTHOR]

Computer-Aided Engineering (CAE) has supported the industry in its transition from trial-and-error towards physicsbased modelling, but our ways of treating and exploiting the simulation results have changed little during this period. Indeed, the business model of CAE centers almost exclusively around delivering base-case simulation results with a few additional operational conditions. In this paper, we describe a new paradigm for treating and exploiting simulation data: instead of reporting simulations of base-case and additional scenarios, databases covering a wide spectrum of operational conditions are built on the basis of simulation data with machine learning algorithms.We refer to the end product resulting from hybrid physics-based and data-driven modelling as Simulation Digital Twin. While the approach is suitable for all sorts of CAE applications, the present contribution addresses the fluid-flow simulation (CFD) sub-branch of CAE. [ABSTRACT FROM AUTHOR]

The paper deals with the applications of modeling and simulation tools in the optimization of business processes, especially in solving an optimization of signal flow in security company. As a modeling tool was selected Simul8 software that is used to process modeling based on discrete event simulation and which enables the creation of a visual model of production and distribution processes. [ABSTRACT FROM AUTHOR]

The search for sets of good interpolation points is highly motivated by the fact that, due to the finite precision of digital computers, valid results can only be expected when the interpolation problem is well-conditioned. The conditioning of polynomial interpolation and of rational interpolation with preassigned poles is measured by the respective Lebesgue constants. Here we summarize the main results with respect to the Lebesgue constant for polynomial interpolation and we present the best Lebesgue constants in existence for rational interpolation with preassigned poles. The new results are based on a fairly unknown rational analogue of the Chebyshev orthogonal polynomials. We compare with the results obtained in [1] and [2]. [ABSTRACT FROM AUTHOR]

The classical paradigm of the neural brain as the seat of human natural intelligence is too restrictive. This paper defends the idea that the neural ectoderm is the actual brain, based on the development of the human embryo. Indeed, the neural ectoderm includes the neural crest, given by pigment cells in the skin and ganglia of the autonomic nervous system, and the neural tube, given by the brain, the spinal cord, and motor neurons. So the brain is completely integrated in the ectoderm, and cannot work alone. The paper presents fundamental properties of the brain as follows. Firstly, Paul D. MacLean proposed the triune human brain, which consists to three brains in one, following the species evolution, given by the reptilian complex, the limbic system, and the neo-cortex. Secondly, the consciousness and conscious awareness are analysed. Thirdly, the anticipatory unconscious free will and conscious free veto are described in agreement with the experiments of Benjamin Libet. Fourthly, the main section explains the development of the human embryo and shows that the neural ectoderm is the whole neural brain. Fifthly, a conjecture is proposed that the neural brain is completely programmed with scripts written in biological low-level and high-level languages, in a manner similar to the programmed cells by the genetic code. Finally, it is concluded that the proposition of the neural ectoderm as the whole neural brain is a breakthrough in the understanding of the natural intelligence, and also in the future design of robots with artificial intelligence. [ABSTRACT FROM AUTHOR]

Reactive behavior is still considered and the exact opposite for the anticipatory one. Despite the advances on the field of anticipation there are little thoughts on relation with the reactive behavior, the similarities and where the boundary is. In this article we will present our viewpoint and we will try to show that reactive and anticipatory behavior can be combined. This is the basic ground of our unified theory for anticipatory behavior architecture. We still miss such compact theory, which would integrate multiple aspects of anticipation. My multi-level anticipatory behavior approach is based on the current understanding of anticipation from both the artificial intelligence and biology point of view. As part of the explanation we will also elaborate on the topic of weak and strong artificial life. Anticipation is not matter of a single mechanism in a living organism. It was noted already that it happens on many different levels even in the very simple creatures. What we consider to be important for our work and what is our original though is that it happens even without voluntary control. We believe that this is novelty though for the anticipation theory. Naturally research of anticipation was in the beginning of this decade focused on the anticipatory principles bringing advances on the field itself. This allowed us to build on those, look at them from higher perspective, and use not one but multiple levels of anticipation in a creature design. This presents second original though and that is composition of the agent architecture that has anticipation built in almost every function. In this article we will focus only on first two levels within the 8-factor anticipation framework. We will introduce them as defined categories of anticipation and describe them from theory and implementation algorithm point of view. We will also present an experiment conducted, however this experiment serves more as explanatory example. These first two levels may seem trivial, but growing interest in implicit anticipation and reactive anticipation in last two years suggest that this is worthwhile topic. The simplicity of them is intentional to demonstrate our way of thinking and understanding of the topic. The comparison with other results is possible only when these levels are integrated into the complex architecture, as will be shown below that can also act as standalone. [ABSTRACT FROM AUTHOR]

Structural damage detection is a very important research topic and, currently, there are not specific tools to solve it. A promising tool that can be used is the artificial neural network, ANN, which can deal with hard problems. This paper uses a back propagation ANN with Bayesian regularization training to locate and quantify damage in truss structures. The input parameters corresponded to natural frequencies combined with shape modes, modal flexibilities or modal strain energies. The ANN was trained by considering only simple damage scenarios, random multiple damage scenarios or a combination of them. The results are shown in terms of the percentage of cases in which the ANN trained achieves a determined performance in assessing both the damage extension and the presence of damaged elements. The best performance for the ANN is obtained by using modal strain energies and multiple damage scenarios. [ABSTRACT FROM AUTHOR]

‘Machine Consciousness’, which some years ago might have been suppressed as an inappropriate pursuit, has come out of the closet and is now a legitimate area of research concern. This paper briefly surveys the last few years of worldwide research in this area which divides into rule-based and neural approaches and then reviews the work of the author’s laboratory during the last ten years. The paper develops a fresh perspective on this work: it is argued that neural approaches, in this case, digital neural systems, can address phenomenological consciousness. Important clarifications of phenomenology and virtuality which enter this modelling are explained in the early parts of the paper. In neural models, phenomenology is a form of depictive inner representation that has five specific axiomatic features: a sense of self-presence in an external world; a sense of imagination of past experience and fiction; a sense of attention; a capacity for planning; a sense of emotion-based volition that influences planning. It is shown that these five features have separate but integrated support in dynamic neural systems. [ABSTRACT FROM AUTHOR]

The current state of development of Computational Electrochemistry is briefly discussed, and a unifying view of the field is proposed, with the aim of stimulating a communication between, and unity of, computationally oriented electrochemists involved in diverse kinds of computations. The most recent work of the author, pertaining to the field, is also reviewed. [ABSTRACT FROM AUTHOR]

Simulating the forming process for sheet metal parts is currently the standard for guaranteeing feasible manufacturing at the time of tool design. In contrast simulating springback and its computer-supported compensation is still under development. The status of the technology for simulating springback will be illustrated and demonstrated using examples. Various strategies related to compensation of shape deviations due to springback will be discussed and explained using examples. The necessary steps for the use of computer-aided simulation and compensation of springback are illustrated for an inner part. The example shows how the simulation of springback can be integrated into the development process of a deep-drawing tool to determine the compensation of the tool surfaces — based on the springback results — before tool production. Another example demonstrates how a new draw die design, that minimizes or eliminates the shape deviation, can be quickly determined from the springback-related shape deviations using special software. The principle of the procedure for compensating for shape deviation and problems that could still occur are explained. The possibilities and limits of the “springforward” compensation procedure are also discussed. © 2005 American Institute of Physics [ABSTRACT FROM AUTHOR]