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The finite-difference method for solving a nonlinear two-point boundary value problems consists of discretization and solving the resulting system of nonlinear equations, usually by the Newton’s method. In this paper, we modify Newton’s method to solve the system of nonlinear equations related to the discretization of a special class of the nonlinear two-point boundary value problems, where y′′is expressed as a multivariate polynomial in y and y′. In the proposed method, the new iteration point is determined as the minimal point of the square of 2-norm of residuals along Newton direction. The minimal point is computed using the solution of a univariate polynomial equation. The numerical examples show that the proposed method performs better than the standard Newton’s method with the unit step length.

Performance of memory allocation and garbage collection algorithms depends on many factors. These factors are mutually depedent and usually cannot be easily observed or measured since they are part of programmming language implementation. Therefore, we propose and implement a simulator, which enables the modelling and simulation of different memory-related processes. Organization of the simulator is described, followed by two examples of its usage for comparison of memory allocation and garbage collection algorithms.

A novel derivative-free algorithm for solving quasi-linear systems is presented. It resembles “classical” optimization approach but greatly simplifies computation, resulting in fast execution and numerical stability. Though the global convergence cannot be guaranteed, it turns out that the presented algorithm finds a solution as successfully as other commonly accepted methods. The algorithm is clearly developed and mathematically founded, and its properties are examined by comparisons with other methods.

One of the main principles of the smartphone and tablet operating systems is simplicity and accessibility. This feature was usually not available on the embedded systems and devices. By connecting these two types of devices, user interface and accessibility can be simplified. A myriad of new possibilities can be added to the embedded systems while giving smartphone and tablet users control over the external devices. The goal of this project is to create and build a fully functional model of a remotely controlled boat controllable through a mobile application. Connection is established through standard Bluetooth protocol and users are presented with the readings of the sensors found on the model. Boat is controlled by rotating the mobile device laterally and longitudinally and has the ability to change velocity or steer away from the obstacles.

The aim of this paper is to propose various comparison criteria for reconfigurable processor architectures and to give an overview of the specification methods for them. The main contribution of this paper is a proposal of the new ontology-based representation of reconfigurable processor architectures.

In this paper two different methods for non-technical losses (NTL) detection are analyzed and new approach is proposed, based on the noticed drawbacks. It is shown that NTL can be successfully detected by a neural network trained by “artificial”, i.e., generated samples. This approach eliminates the need for many hard-to-obtain real life samples and the network can easily be trained to detect some new, nontypical occurrences in the system. This makes the proposed solution suitable for large companies that supply many different consumers who possibly change their consumption habits.

This paper describes mathematical modelling of traditional graphic structures within textile materials using binary matrices, which is made possible by the binary nature of these structures. An algorithm is presented for woven design construction (weave draft, threading draft, treadling draft and tie-up), as well as an algorithm for weave reinforcement using binary matrices. The general advantage of the algorithm is its simplicity and execution speed. Application of the weave reinforcement algorithm is also presented in this paper, and the computer program, written in C#, shows the ease of its implementation, opening the way to integration into existing and new CAD/CAM packages.

Prospective liberalization of European electrical energy market requires appropriate technological support because of increasing demands on energy quality control and measurement accuracy. This paper considers one possible direction of the development of highly accurate electronic energy meters based on spectral analysis. The concept is explained theoretically and justified by results obtained with a prototype. Important advantages and drawbacks are recognized, and directions for further development provided.

A simulation model of the radar network operation of five military radar stations has been developed. Simulation was performed in GPSS language and contains the time of operation of five radars through a period of one year, time of planned preventive maintenance, irregularities, time of corrective maintenance and maintenance teams. The simulation shows the influence of the number of maintenance teams on the availability of each radar and presents a good orienteering point for defining the optimal model of preventive and corrective maintenance of the radar network.

This paper describes the modelling language GPSS++. One of the main purposes of the language is its use in education. It extends the well-known discrete-event modelling language GPSS in several aspects, among which an object-oriented modelling is one of the most important. Other extensions of GPSS++ are: support for modular and hierarchical modelling, support for hybrid modelling (discrete and continuous), and significantly enhanced features for description of model behaviour (by using features of a general purpose programming languages). Syntax of the language is also modernized. In the same time, GPSS++ tries to retain the basic GPSS concept of modelling that uses transactions and blocks. The paper describes the main features of the GPSS++ mentioned above. Results of comparison of models written in GPSS and GPSS++ are given. The main advantages of GPSS++ over old versions of the language are better organization of the model and improved readability and writeability. Also, the language is better adapted to the programmers with the background in modern and widely used object-oriented languages. In addition, GPSS++ is better suited for larger models due to its modular and hierarchical organization. GPSS++ is currently under development and here we describe its first version and we also give directions for future improvements and research.

This paper describes the design and the implementation of a computer memory simulator which is modular, extensible and portable. It enables the simulation of various memory-related events from the aspect of the running program. The model includes the algorithms for memory allocation, garbage collection, stack behavior, etc. The simulation uses traces obtained by running the actual programs (benchmarks) written in any programming language. The simulator fulfills its main purpose: to simplify the development of algorithms for memory allocation and garbage collection. The algorithms can be easily modeled, validated, tested and compared in order to select the most efficient one.

This paper elaborates the present stage and predictable direction of future development of Sine Wave Calculator (SWC), a simple method for signal analysis in time domain that provides accuracy comparable to the best classical methods (relative errors about few times 10– 6). The main SWC advantages are extreme simplicity, possibility of selection of samples and straightforward calculations, which makes it preferable solution for quick implementation. The main shortage is still unknown mathematical analysis of errors, which are probably unequal for different signal parameters.

This paper elaborates the present stage and predictable direction of future development of Sine Wave Calculator (SWC), a simple method for signal analysis in time domain that provides accuracy comparable to the best classical methods (relative errors about few times 10– 6). The main SWC advantages are extreme simplicity and straightforward calculations, which makes it preferable solution for quick implementation. The main shortage is still unknown mathematical analysis of errors, which are probably unequal for different signal parameters.

The performance of a memory system depends to great extent on the algorithms used for memory allocation and garbage collection (GC). GC implementers need accurate data about memory objects' behaviour in order to produce high quality garbage collectors optimized for their particular problems. Therefore, different GC-related data should be collected and analysed afterwards. We propose a set of parameters that should be traced in benchmark programs and organization of an analysis environment. Then we present several examples of results obtainable by the proposed analysis environment. That results can be useful in improving the existing or in the creation of new GC algorithms. The profiled data are obtained by running benchmarks written in the Java programming language that we use as a representative of the languages that belong to the object oriented programming paradigm.

Extreme complexity of traffic systems imposes two problems in their simulation: the simulation speed, and the model's level of details. The simulation speed is improved by using better simulation algorithms, or by using more processing power. The level of details is managed by the most appropriate modeling scale. The simultaneous usage of multiple scales gives multiscale models. We have implemented a prototype simulator in order to investigate the possibility of using agents in multiscale modeling. The agents model characteristics of vehicles and drivers' behavior. Preliminary experiments have shown satisfactory simulation speed. We plan to enhance the simulator with agents that model road sections in order to support meso- and macroscale models.

Garbage collection (GC) algorithms are often based on beliefs about common behaviour of memory objects. Object behaviour patterns are very different because they depend on many factors (programming paradigm, language execution style, application itself, and programmer's style). There are several proposals and implementations of software for tracing the behaviour of memory objects or trace formats for heap allocation events (HATF).

The performance of memory system depends to great extent on the algorithms used for memory allocation and garbage collection (GC). GC implementers need accurate data about memory objects behaviour in order to produce high quality garbage collectors optimized for their particular problems. Therefore, different GC-related data should be collected and analysed afterwards. We propose a set of parameters that should be traced in benchmark programs and organization of an analysis environment. Then we present several examples of results that can be useful in improvements of performance of the memory system. Data are obtained by running Java benchmarks.

The program package ATLAS (Advanced Tools and Languages for Microprocessor Architecture Simulation) consists of several tools. The most important are COMPAS (Configurable Microprocessor Architecture Simulator) and CONAS (Configurable Assembler).

Simulation methods are widely used in system analysis. An ATLAS digital simulation package is used to model and simulate complete DC motor drive control system. DC motor drive is modeled using transfer functions in Z domain. Controller of the drive is composed of a microprocessor with memory, D/A and A/D converter. Detailed model of a controller and satisfactory approximation of the drive makes possible testing and examining behavior of microprocessor controller. Model implemented in ATLAS enables the determination of optimal hardware and software solution for a desired control algorithm. Described model is extensively used for teaching principles of real time computer control.

This paper proposes and describes the method for performance evaluation and microprocessor bus allocation using a genetic algorithm

In this paper the digital system simulation program package ATLAS (Advanced Tools and Languages for microprocessor Architecture Simulation) is described. Different software modules, parts of ATLAS are developed: COMPAS - COnfigurable MicroProcessor Architecture Simulator, CONAS - CONfigurable ASsembler, ADEL - Assembler DEscription Language, COMDEL- COMponent DEscription Language and SYSDEL - SYStem DEscription Language. The simulator COMPAS and its implementation are explained in more details. The digital component description language features are given.