×

You are using an outdated browser Internet Explorer. It does not support some functions of the site.

Recommend that you install one of the following browsers: Firefox, Opera or Chrome.

Contacts:

+7 961 270-60-01
ivdon3@bk.ru

  • Methods of estimating the adequacy of simulation results

    This paper describes application of different criteria for estimating parameters of traffic simulation. For comparison following methods were used: statistical methods for comparison of a flow and speed in control points of a network - analysis of variance (ANOVA), Theil's U-statistics; relationships between flow, density and speed; relationships between trip time and stop time with using two-fluid models of traffic flow. For this aim we also used concept of meta-model. In order to implement this method we need on the first step to create separately relationship between traffic flow parameters for observation and simulation data and then to estimate combined model. The paper included results of calculation  

    Keywords: validation, traffic, simulation, flow, speed

  • Research the relationship between technological possibility forest machines with the parameters of forest environment

      To estimate the effectiveness of forest machines developed technological possibility coefficient. Coefficients reflect the ability to provide a given performance of transport vehicles in the logging, the decline in the quality of the skid road surface. Method allows determining the amount of logging residues, necessary for the skid road construction. At calculating the available volume accounted for logging residues. Resources of logging residues are calculated depending on the type of timber and the length of skid road. The method allows selecting the optimum system of machines to work in these natural production conditions or schedule performance loss due to reduced carrying capacity of skid road.

    Keywords: Cross country, technological passableness, forest machines, bearing capacity of soils, skid road, wood types, logging residues

  • Inductance per unit length of twisted pair at microwave frequencies

    Proposed an approach to calculate the inductance per unit length of twisted pair at microwave frequencies. Analytical relations to calculate the inductance per unit length of double line and twisted pair at microwave frequencies. An efficient algorithm for the approximate calculation of the inductance per unit length of twisted pair at any veins angle.

    Keywords: inductance per unit length, microwave frequency, twisted pair, double line, veins angle

  • Using of modeling of the road motion for estimation of the ecological condition is exposed-road network

    In the publication the problematics of an estimation of emissions of polluting substances from motor transport is stated. Aplying foreign experience in estimation of the ecological situation at modelin  

    Keywords: soiling the air pool, surge polluting material from motor transport, features of the transport flow.

  • The analysis of on-line transaction processing systems’ model with replication of database fragments designed by using principles the cloud environment

      The model of on-line transaction processing system architecture constructed by a principle of cloud structure is considered. The mathematical model of OLTP-system as the queuing system is offered. Results of modeling and their analysis are led.

    Keywords: On-line transaction processing system, Cloud architecture, Distributed database, Queuing system

  • Development of defensive infrastructure in the St. Petersburg agglomeration

      Describes the status of defense infrastructure of Saint-Petersburg agglomeration, in the transport, engineering and social, and proposed the ways of its perspective development.

    Keywords: urban agglomerations, city, frame, transport, defense, defense infrastructure

  • A new approach to provide web accessibility for the blind users based on the enhance of navigational characteristics of web pages

    Most of web pages of the Web are inaccessible for the blind users. And the main reason is a lack of the semantics at the source code (technical) level of web pages and absence of the navigational components. In this work we propose a new web page representation---multiaxial navigation model---representing web documents in the form convinient for the blind users. Moreover, we present methodology for the navigation on the model proposed, that ensure an efficiency of user mobility. Automatic transformation of a web page into the multiaxial navigation model and navigation means are realized in the Blindzilla prototype. An efficiency of the proposed concepts is proven experimentally regarding contemporary screen readers, such as JAWS, Window-Eyes, and Fire Vox.

    Keywords: web accessibility, navigation, web page, web technologies

  • Propagation of acoustic waves in water supply systems with varying diameter pipes

    In operation the case when the radiant of an acoustic signal is in a composite cylindrical pipe is viewed. It is shown, that at transition of a pipe of one diameter in a pipe of other diameter, it is expedient to apply modal representation of an acoustic wave to each site of a pipe.

    Keywords: acoustics, the control, diameter, waterpipe

  • Cognitive approach to the research of geopolitical processes in world regions and cognitive modeling of their development (On the example of the Black – Caspian Region)

      The article is devoted to the problem of the research of geopolitical processes on the world regions’ scale under present-day conditions. The article substantiates the necessity of their analysis with the help of the cognitive approach as an effective means of cognition of the interconnections and interrelationships within the complicated systems. With that aim in view the specifics and the stages of the cognitive modeling are given thorough analysis in the article. This type of modeling is adapted to the analysis of geopolitical dynamics on the regional/sub regional level taking into consideration its aptitudes to make prognostic scenarios of the development of the situation. The possibilities of the cognitive modeling of geopolitical processes are illustrated on the example of the situation in three sub regions constituting one (big) the Black Sea – Caspian region.

    Keywords: World regions, geopolitical processes, modeling of the complicated systems, modeling of the geopolitical processes, cognitive modeling, the program’s system of the cognitive modeling, the Black Sea – Caspian Region, the Black Sea sub region, the Caucasus

  • Numerical solution for a plane area containing the unknown interface

    The numerical algorithm consists of in determination of a minimum of some functional, defined in the area containing in advance unknown interface. The unknown interface is obtained from a minimization condition of the functional together with unknown functions. The problem for plane area dares a method of grids.

    Keywords: algorithm, functional, minimum, genetic algorithm, grid, function, area, interface

  • To a question on defense of the St.-Petersburg agglomeration (town-planning aspect)

    The facts allowing scientifically are analyzed - to prove participation of a town-planning science with a view of accommodation of military force in territory of the state, and in particular the St.-Petersburg agglomeration. Also problems in town-planning maintenance of agglomeration to defense are stated.

    Keywords: urban agglomerations, city, armed forces, defense, territory

  • Multicriteria decision making under risk based on the integration of multi-agent, evolutionary modeling and numerical methods

    Decision making in the organizational and technical systems is complicated by the risk of various events emergence in the systems with a given probability. The article describes a method for supporting decision making under risk on the basis of integration of evolutionary, multi-agent, simulation models and numerical methods. In the course of the method's work the following steps are performing: a set of alternatives solutions is formed;  transition to a one-criterion alternatives evaluation is fulfilled by using linear convolution; transition to the system behavior certainty is fulfilled with the use of numerical optimization Bayes-Laplace criterion. The developed method is applied to solving the projects scheduling problem; the results agree with the problem solution that has been performed by using genetic algorithm method under certainty.

    Keywords: decision making risks, multi-agent modeling, numerical methods of decisions optimization, scheduling problem, evolutionary modeling

  • Model of system of three-level maintenance of information interaction in the management information system

      In article the information system of the MANAGEMENT information system is represented as the three-level model constructed by a principle of cascade maintenance. Problems of delays of the supply with information, formations arising at the expense of delays and data transmission are considered. The mathematical model of system intended for optimization of maintenance on parameter of delays, on the basis of priorities of processes of formation and an information transfer is developed.

    Keywords: Sirotkin A.V. information supply, information service delay

  • Modifications of BM25 using a genetic algorithm

    The rapidly growing information space combined area networks creates new needs for management, reporting, and especially in the search for data. On the first place there is the criterion of relevance, which allows for its correct use to increase the efficiency of information retrieval. There is a fairly large number of schemes and models for solving search problems, one of which is the BM25.

    Keywords: genetic algorithm, information retrieval, modification BM25

  • Problem analysis of navigation in portable scientific data representation

      Article describes actual problems of personal navigation in portable scientific document set representation. Proposed algorithm for ranking document graph paths based on machine learning, described algorithm analysis and most probable navigation context parts.

    Keywords: Document set navigation, machine learning, navigation context, scientific data visualization