System analysis
Three architectures of the cooperative thread scheduler in a multithreaded application that is executed on a multi-core system are considered. Architecture A0 is based on the synchronization and scheduling facilities, which are provided by the operating system. Architecture A1 introduces a new synchronization primitive and a single queue of the blocked threads in the scheduler, which reduces the interaction activity between the threads and operating system, and significantly speed up the processes of blocking and unblocking the threads. Architecture A2 replaces the single queue of blocked threads with dedicated queues, one for each of the synchronizing primitives, extends the number of internal states of the primitive, reduces the inter- dependence of the scheduling threads, and further significantly speeds up the processes of blocking and unblocking the threads. All scheduler architectures are implemented on Windows operating systems and based on the User Mode Scheduling. Important experimental results are obtained for multithreaded applications that implement two blocked parallel algorithms of solving the linear algebraic equation systems by the Gaussian elimination. The algorithms differ in the way of the data distribution among threads and by the thread synchronization models. The number of threads varied from 32 to 7936. Architecture A1 shows the acceleration of up to 8.65% and the architecture A2 shows the acceleration of up to 11.98% compared to A0 architecture for the blocked parallel algorithms computing the triangular form and performing the back substitution. On the back substitution stage of the algorithms, architecture A1 gives the acceleration of up to 125%, and architecture A2 gives the acceleration of up to 413% compared to architecture A0. The experiments clearly show that the proposed architectures, A1 and A2 outperform A0 depending on the number of thread blocking and unblocking operations, which happen during the execution of multi-threaded applications. The conducted computational experiments demonstrate the improvement of parameters of multithreaded applications on a heterogeneous multi-core system due the proposed advanced versions of the thread scheduler.
The article discusses the approach to modeling of metamorphoses in the development of a number of species in the context of their influence on the success of long-term trends of population dynamics. Changes in survival during early ontogenesis, controlled by important factor – the rate of individual development in a competing group of individuals, can cause unexpected degradation of population with a small excess fishing impact. The theory of nonlinear efficiency of reproduction leads us to the hypothesis that two different nonlinear effects are controlled by similar mechanisms. For insects such fluctuations in survival during metamorphosis can start another process - the rapid outbreak of pests, where actual formalization of the impact of parasites on the first stage of development, depending on the initial concentration of clutches, but limited resources is taken into account at a finishing. The method has been for submission to decline of generations on the basis of dynamic overriding differential equations with discrete-continuous structure of time. To extend the previously proposed model for the formation of generations is formed computing structure for the account mortality depending on the level of competition, complete with trigger functional and a new scheme describing the changes the growth rate for the example of the Caspian Sea sturgeon in three ecological and physiological stages of development. The new model has a non-trivial possibilities parametrically modification of behavior regimes. The coexistence of alternative cycles is explained by the increase in adaptive interspecies differences.
This paper presents results of a comparative analysis of 34 measures published in the scientific literature and used for evaluation of the image quality without a reference image. In English literature, they are called no-reference (NR) measure or measures NR-type. The first article, the term no-reference, was published in 2000 and each year a growing number of publications on new measures NR-type. However, comparative studies of such measures is not practically conducted. Such measures are very important for a) just made photo quality evaluation, b) assessment of image enhancement transformations and selection of their parameters (such as contrast and brightness adjustments, tone-mapping, decolorization and others). Publicly available image quality databases used for study no-reference quality measures (TID2013, etc.), contain 4-5 variants of images distorted by predefined transformations with unknown parameters. We presented six types of experiments to analyze correlation of the computed numerical quality values with visual estimates of the test images quality. Four of the experiments are new: comparison of images after gamma-correction and contrast enhancement with different parameters, as well as analysis of the retouched images and photos taken with different focal length. It was shown experimentally that no one of the known no-reference quality assessment measure is universal, and the calculated value cannot be converted to a quality scale, excluding factors influencing the distortion of the image. Most of the studied measures calculates local estimates in small neighborhoods, and their arithmetic mean is the quality index of the image. If the image contains large areas of uniform brightness, the measures of this type can give incorrect quality assessment, which will not correlate with the visual assessments.
It is shown that the maximally full description of vita-medium with “the substantially sensor system” on the basis of expressed syntax properties implies introduction of complex assertions of experts built on elementary estimates. Natural conditions of determinacy and completeness are put on multiple models by corresponding to all sensor components which control vita-medium properties. The trueness of assertions by experts and inadequacy measure of vita-medium properties provision have been considered in the process of sensor control.
It is shown that thermodynamics ideas of informational processes can be used for the generalized description of vita-medium during sensor control of its properties. In order to find out thermodynamic regularities of the censor control procedure the series circuit of conversions is considered: object property – controlled parameter – feature distortion – generalized coordinate – information model. During the high precision control the information quantity is determined with the aid of relative precision logarithm, and in case of comparatively rough determination of vita-medium parameters it depends on the square of sensor control relative precision.
Reasons and consequences of distorted sensor images have been considered with the use of technical means of outlines of events and vita-medium properties provision. A contradictory, two-value character of impact on the process of control of extra technical means is shown, which are included between the controlled object and “the subjective sensor system”. Probability of provision of successful collection, procession, accumulation and renewal of information on vita-medium parameters with intelligent system means has been analyzed.
Management of technical objects
Classical method of designing electric motors help to achieve functional motor, but doesn’t ensure minimal cost in manufacturing and operating. Recently optimization is becoming an important part in modern electric motor design process. The objective of the optimization process is usually to minimize cost, energy loss, mass, or maximize torque and efficiency. Most of the requirements for electrical machine design are in contradiction to each other (reduction in volume or mass, improvement in efficiency etc.). Optimization in design permanent magnet synchronous motor (PMSM) is a multi-objective optimization problem. There are two approaches for solving this problem, one of them is evolution algorithms, which gain a lot of attentions recently. For designing PMSM, evolution algorithms are more attractive approach. Genetic algorithm is one of the most common. This paper presents components and procedures of genetic algorithms, and its implementation on computer. In optimization process, analytical and finite element method are used together for better performance and precision. Result from optimization process is a set of solutions, from which engineer will choose one. This method was used to design a permanent magnet synchronous motor based on an asynchronous motor type АИР112МВ8.
The main requirement to imitating modeling of military operations adequacy. Proceeding from it is necessary that the behavior of modeling objects has been as much as possible approached to behavior of real objects in the same conditions of conditions or, at least, did not contradict logic of common sense and requirements of authorized documents. It creates necessity of working out of the mechanism, allowing to formalize administrative experience of commanders of corresponding levels and automatically to deduce decisions, on the basis of parameters of a current situation and preliminary set solving rules.
As a rule, in decision-making process, the commander operates with difficult formalizable information at level of complex categories. Contrary to it, the object condition in modeling system is described in the form of a set of values of concrete parameters. For transformation of set of parameters of objects to parameters of higher level the method of the analysis of hierarchies is used.
Thus there is the second problem demanding the permission synthesis of the device of decision-making on the basis of the received complex concepts. Use of the mechanism of an indistinct logic conclusion for this purpose is offered. In this case preference of a choice of this or that variant of behavior is set depending on character of crossing of the indistinct sets defined by the expert which functions of an accessory are constructed on axes generated before complex parameters. In quality konsekvents solving rules in advance generated strategy of behavior of modeling objects in this connection in offered algorithm actually there is no stage defuzzyfication act, and for accumulation of the conclusions the formula of algebraic association is
used. The offered approach allows to carry out an automatic choice of alternative of behavior during modeling without participation of the operator.
Data processing and decision–making
The modified algorithm of the adaptive compensating of the active noise jamming, based on usage of the recurrence estimation of inverse covariance matrix of jamming in the course of an self-tuning is considered. The matrix estimation is formed by a method of a serial regression (SRM), a consequence application of a lemma about inversing of a matrix to differential – to the difference equation for a rounded estimation of direct covariance matrix of jamming (CMJ). The single estimation of straight line CMJ is formed as result dyad products of the instant vectors of noises in handling channels. In partial channels the adaptive transversal filters with the self-tuning on value of a signal of an aggregate error are implemented.
In article skeleton diagrams of devices of the compensating implemented by various methods are resulted. Mathematical modeling of operation of the algorithms, implemented by a method of the least squares (criterion of a minimum RMS error) and a method of a serial regression is performed.
Results of mathematical modeling of operation of the device of compensating of active noises jamming in the conditions of the active radio-electronic counteraction at multipath propagation of signals both non-identical amplitude and phase characteristics of channels of handling are resulted. Optimal values of technical parameters of devices of compensating of the active noises jamming providing obtaining of demanded values of coefficient of suppression are given. The comparative analysis of indexes of efficiency of classical and offered algorithms of compensating is made. Advantage of algorithm of compensating of the active noises jamming, using the recurrence estimation of a inverse covariance matrix of jamming is shown.
The algorithm of functioning on the basis of SRM allows to lower essentially requirements to specialized VLSI (FPGA) at implementation is hardware – program complexes for preprocessing of the radar, radio communication and radio – navigation information in the conditions of influence of the active noises jamming in the presence of effects of multipath propagation of signals, in the presence of delay of signals on an antenna system aperture, and also at unremovable technological dispersion amplitude and phase characteristics of the microwave of channels of handling.
This paper introduces the design and development of QMRS (Quadcopter Mobile Robotic System). QMRS is a real-time obstacle avoidance capability in Belarus-132N mobile robot with the cooperation of quadcopter Phantom-4. The function of QMRS consists of GPS used by Mobile Robot and image vision and image processing system from both robot and quad-copter and by using effective searching algorithm embedded inside the robot. Having the capacity to navigate accurately is one of the major abilities of a mobile robot to effectively execute a variety of jobs including manipulation, docking, and transportation. To achieve the desired navigation accuracy, mobile robots are typically equipped with on-board sensors to observe persistent features in the environment, to estimate their pose from these observations, and to adjust their motion accordingly. Quadcopter takes off from Mobile Robot, surveys the terrain and transmits the processed Image terrestrial robot. The main objective of research paper is to focus on the full coordination between robot and quadcopter by designing an efficient wireless communication using WIFI. In addition, it identify the method involving the use of vision and image processing system from both robot and quadcopter; analyzing path in real-time and avoiding obstacles based-on the computational algorithm embedded inside the robot. QMRS increases the efficiency and reliability of the whole system especially in robot navigation, image processing and obstacle avoidance due to the help and connection among the different parts of the system.
Information security
Practical application of advanced algebraic constructions in modern communication systems based on MC-CDMA (Multi Code Code Division Multiple Access) technology and in cryptography necessitates their further research. One of the most commonly used advanced algebraic construction is the binary bent-function having a uniform amplitude spectrum of the Walsh-Hadamard transform and, accordingly, having the maximal distance from the codewords of affine code. In addition to the binary bent-functions researchers are currently focuses on the development of synthesis methods of their many-valued analogues. In particular, one of the most effective methods for the synthesis of many-valued bent-functions is the method based on the Agievich bent-squares. In this paper, we developed a regular synthesis method of the ternary bent-squares on the basis of an arbitrary spectral vector and the regular operator of the triad shift. The classification of spectral vectors of lengths N = 3 and N = 9 is performed. On the basis of spectral classification more precise definition of many-valued bent-sequences is given, taking into account the existence of the phenomenon of many-valued bent-sequences for the length, determined by odd power of base. The paper results are valuable for practical use: the development of new constant amplitude codes for MC-CDMA technology, cryptographic primitives, data compression algorithms, signal structures, algorithms of block and stream encryption, based on advanced principles of many-valued logic. The developed bent-squares design method is also a basis for further theoretical research: development of methods of the permutation of rows and columns of basic bent-squares and their sign coding, synthesis of composite bent-squares. In addition, the data on the spectral classification of vectors give the task of constructing the synthesis methods of bent-functions of lengths N = 32k+1, k Є ℕ.
Information technologies in education
Using of learning management systems increases the possibility of teachers and students in achieving their goals in education. Such systems provide learning content, help to organize and to monitor training progress, help to collect statistics. However, the transition from one LMS to another there is a problem of content migration, because all training materials and tests should either be recreated, or somehow be migrated to the new system. Content migration by hand is a very time-consuming process, so the leading developers of the learning management systems developed a standard for the organization and storage of content, called SCORM (Eng., Sharable Content Object Reference Model). Created by this standard, the content must migrate to the learning management system provided its support for these systems. SCORM standard allows you to create training content that is not dependent on the learning management system, but the loosely embedded in it. This approach enables teachers to develop unique courses and put them free available or for sale in the Internet for all interested persons, and to use educational content created by the best specialists around the world to carry out their activities. The content on the SCORM standard imposes certain requirements on the learning management systems, as they do not distort the training content and properly interact with the tests. The aim of this article is a software implementation of a content migration by SCORM standard from other learning management systems in its own development used at the Software Department of the Faculty of Information Technology and Robotics of the Belarusian National Technical University.
ISSN 2414-0481 (Online)