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PROCEEDINGS OF THE 8TH INTERNATIONAL CONFERENCE RELIABILITY AND STATISTICS IN TRANSPORTATION AND COMMUNICATION (RELSTAT-08), 15-18 OCTOBER 2008, RIGA, LATVIA, ISBN 978-9984-818-11-5

ON A COPULA FOR A RELIABILITY FUNCTION OF A MULTICOMPONENT SYSTEM 

Alexander Andronov

Riga Technical University
Kalku str. 1, Riga, Latvia, LV-1658
E-mail: Aleksandrs.Andronovs@rtu.lv

A considered reliability system consists from n identical elements. Each element can be available or failed. A failure rate of element equals to λ / i, where i is a number of available elements. Time till a failure of an element has exponential distribution. Independence property has place too. Therefore total failure rate is the constant λ, until at last one element is available. Initially all elements are available. The main aim of the paper is to determine a joint distribution of the available time for all elements, as so as a corresponding copula. It allows us to generalize gotten results on unexponential case.
Keywords: multi-component system, reliability function, copula

DYNAMIC MODELLING OF AIRCRAFT COMPOSITE METALLIC THIN-WALLED CONSTRUCTION SHAPING ELECTROMAGNETIC PROCESS 

Victor Astapov, Alexander Silouyanov, Roman Chernyavsky, Leonid Khoroshko

"МАTI" - Russian State Aviation Technological University
Orshanskaya 3, Moscow, 121552, Russia
Ph.: 8 495 1419502. E-mail: Khoroshko@mati.ru

The presented paper “Dynamic modelling of aircraft composite metallic thin-walled construction shaping electromagnetic process” reviews the axisymmetric blank assembly process with magnetic impact metal processing method. Shell junction formation process is divided into three basic stages: free shifting stage, consequent shifting stage and unloading stage. According to a numeric resolution of shifting equalities, a axisymmetrical metal composite formation process is modelled for each stage. On basis of the model developed, real time tubular jointment creation kinematics was studied from 0 time up to time of deformation process termination, i.e. creation of hermetic construction, that allows to determine time and speed characteristics of wall movement while pressing the aluminium blank. To learn magnetic impact assembly process, contemporary 3rd graphics systems are used.
Keywords: dynamic modelling, electromagnetic process, aircraft CONSTRUCTION, free shifting stage, consequent shifting stage, unloading stage, 3rd graphics systems

MOBILE DECISIONS OF TRANSPORTATION OF DANGEROUS GOODS 

Nijole Batarliene Vilnius Gediminas

Technical University (VGTU)
Department of Transport Management
Plytines str. 27, Vilnius-16, LT-10105, Lithuania
Ph: +370 52370634.
Fax: +370 52745059.
E-mail: nijbat@ti.vgtu.lt

This paper presents several ideas of effective transport systems technologies, technological solutions in systems for identification objects on the road for dangerous goods transport. In the article the coherence of new technologies and new possibilities for location and control of cargo and vehicles with systems of positioning system, location system standards are theoretically shown. A remote identification system for freight transport allows new possibilities of differential GPS (GNSS) techniques and applications for dangerous goods safe transportation.
Keywords: transportation, dangerous goods, location, vehicle, mobile decisions

BUSINESS DEVELOPMENT IN LITHUANIA THROUGH INNOVATIVE INFORMATION TECHNOLOGIES 

Darius Bazaras1, Ramunas Palsaitis2

Vilnius Gediminas Technical University
Department of Transport Management
Plytines str. 27, Vilnius-16, LT-10105, Lithuania
Ph: +370 852744776,
Fax: +370 852745059
E-mail: 1dbazaras@vv.vtgu.lt, 2trvadyba@ti.vtgu.lt

Information and Communication Technologies (ICT) play very significant role in logistics management, so trade companies and manufacturing industry have a big demand of such systems, because there exist lots of information, which must be quickly processed, evaluated and, if it’s necessary, given to customers. The purpose of the current survey is to give an overview about the ICT situation, usage and development among Lithuanian companies, covering both infrastructure and service areas. The respondents of the survey were mainly SMEs from logistics, manufacturing, trading and other industries. From other results confirmed by this survey, including lack of ICT personnel, lack of tailored solutions for the companies and from the positive side open mindedness of Lithuanians for using ICT in their everyday work.
Keywords: information technologies, business management, logistics, marketing

THE APPROACH TO CONSTRUCTION OF SIMULATION MODEL FOR URBAN TRAFFIC FLOWS ROUTING ON THE BASIS OF THE COMPUTER NETWORKS DYNAMIC ROUTING PROTOCOL OSPF 

Alexander Berezhnoy, Konstantin Chudinov

Transport and Telecommunication Institute
Lomonosova str. 1, Riga, LV-1019, Latvia
Ph.: +371 29110030, +371 26481880. E-mail: avb@tsi.lv

In the given research the alternative approach to the decision of a problem of traffic flows management in the city scale is offered. Using a similarity method the comparative analysis of major control principles in the areas of transport systems and computer networks is realized. It is proposed to apply the computer networks dynamic routing protocols for arranging the information management and control of vehicular traffic. General requirements to development of simulation model for solving the given problem are formulated, base structural elements are developed and the model for the arbitrary topology of street road network is constructed. The analysis of simulation results is carried out.
Keywords: traffic management and control, street road network, computer networks, dynamic routing protocols, simulation modelling

INVESTIGATION OF FUNCTIONAL AVAILABILITY FOR THE NETWORK ACCESS POINTS INFRASTRUCTURE 

Alexander Berezhnoy, Jelena Levshina

Transport and Telecommunication Institute
Lomonosova str. 1, Riga, LV-1019, Latvia
Ph: +371 29110030, +371 29647434.
E-mail: avb@tsi.lv

The given research deals with the analysis of computer network infrastructure for the purpose of outbound access to the company information resources and Internet global network. For this purpose network infrastructure chains supporting the key information services are selected. The construction of the conditions graph for the network access point service chains is carried out. The transformation of conditions graph and evaluation of reliability indexes such as final state probabilities and availability coefficient is made.
Keywords: reliability, conditions graph, availability, computer network access point, information services

THE COMPARISON OF COST REGIONAL PASSENGER TRANSPORTATION IN LITHUANIA RAILWAY AND ROAD TRANSPORT 

Jonas Butkevicius1, Aldona Jarasuniene2

Vilnius Gediminas Technical University
Transport Research Institute
Plytines str., 27, LT-10105, Vilnius-16, Lithuania
Ph: +370 2370633, +3702745076.
Fax: +370 2745059, +370 2699711
E-mail: 1jonas.butkevicius@ti.vgtu.lt, 2ajarasuniene@yahoo.com

The railway and road transport are rival in the regional passenger transportation of the country. The cost is a general index of passenger transportation. So, this article deals with the cost of the regional passenger transportation in the railway and road transport. The cost is comparable to 1 passenger kilometres, according to train types and according to expense elements. There are described the factors influenced to the cost transportation in the every transport means in the given study.
Keywords: regional passenger transportation, railways and roads transport, train, bus, cost, route

MODELLING DISTURBANCES IN SYSTEM TRACK – RAIL VEHICLE 

Tadeusz Cisowski1, Andrzej Niewczas2, Józef Stokłosa3

High School of Economics and Innovation
Melgiewska str. 7/9, 20-209 Lublin, Poland
1Ph: +48 483617762, t.cisowski@pr.radom.pl
2Ph: +48 815384258, a.niewczas@pollub.pl
3Ph: +48 483617751, j.stoklosa@pr.radom.pl

All real systems work in disturbances conditions. “Disturbances” term belongs to special category of entry values which are not known before and do not make subject to control, it means they are uncontrolled entry signals. Disturbances are an important element of systems regulation, because usually lead to unexpected effects in functioning of steered systems. An alternative approach has been proposed in this article in disturbing signals description, related on theory of wave disturbances, which allow to describe wide disturbances scale, occurred in suspensions of active vehicles. Disturbances models based on new wave interpretation can describe wide class of real, indefinite disturbances which occur in suspensions of active vehicles.
Keywords: suspensions, active vehicles suspensions, wavy interpretation of disturbances, Laplace transform, random disturbances

RESEARCH OF STUDY SUBJECTS’ INTERCONNECTION FOR TRANSPORT AND LOGISTICS EDUCATIONAL PROGRAMS 

Nadezda Fila1, Boriss Misnevs2

Transport and Telecommunication Institute
Information Technology Department
Lomonosova str. 1, Riga, LV-1019, Latvia
1Ph. +371 67100596, e-mail: nf@tsi.lv
2Ph. +371 67100675, e-mail: bfm@tsi.lv

The purpose of the paper is to present the methodology and its implementation results in the field of statistical research of TTI study process trends by use of analytical system. The actual analytical system (AS TTI) for data maintenance and analysis was created at Transport and Telecommunication Institute (TTI) based on the OLAP principle [1]. The paper represents experimental results of the analytical system implementation for statistical research of study subjects’ interconnections for transport and logistics educational programs. Advanced technology allows users to perform a multidimensional data analysis for decision making purposes. The system uses independent Data Marts, which are constructed basing on information delivered from actual TTI Information System (OLTP). The paper emphasizes one of the analytical tasks of study processes management at the university, which has been solved using the AS TTI Data Mart “Analysis of examinations marks for study subjects at different study programs. As the example of the suggested methodology some correlation coefficients were calculated and analyzed to characterize examination marks interdependency between study subjects for several educational programs in the transport and logistics area. As the result factually existing study subject interconnection was recognized on the base of correlation analyses. The analytical methodology implemented in the AS TTI was recommended as an eventual tool for investigation of study subjects’ interconnection, aimed to improve the quality of educational programs.
Keywords: the University Analitical System, OLAP-technology and Data Marts

MAIN TASKS FOR THE SUCCESSFUL DEVELOPMENT OF THE LOGISTICS CENTRE 

Olga Girvica

66 North Delivery and Logistics
Jurmalas str., Pinki, Babites district, Riga, Latvia
Ph: 29203422, e-mail: olga@66north.lv

One of the main objectives for any logistics company is to simplify the supply chain, minimize storage and maximize speed and efficiency for delivery of goods.
Keywords: Logistics centre tasks

CONCEPT OF INTELLIGENT SYSTEM FOR OPERATIONAL PLANNING AND OPTIMISATION OF INTRA-CITY SUPPLY CHAINS 

Alexander Grakovski, Igor Kabashkin, Anatoly Ressin

Transport and Telecommunication Institute
Lomonosova str.1, Riga, LV-1019, Latvia
Ph: +371 67100654,
e-mail: avg@tsi.lv

Currently in the city of Riga there are several parallel, independent of each other, networks for delivery goods. It is noteworthy that, unlike the major networks, companies doing outsourcing cannot provide the routes full load vehicles and the best routes. In the central part of the city near the same streets perform different trucks delivering goods to customers of neighbouring addresses. The movement, parking and downloading of vehicles produced during the working day and during peak hours, sometimes without taking a single lane road. This creates additional problems for urban traffic, pedestrians and the urban environment. The situation could be improved by creation of a virtual segment of intellectual transport system, planning the work of small transport companies (SME) that work on outsourcing of logistics centres. The concept of such a system is in creation of the Internet-portal for linking customers and freight transport companies.
Keywords: intelligent transport systems, supply chains, optimisation, vehicle routing problem

THE INFLUENCE OF THE PASSENGERS’ TRANSPORT SYSTEM CONVENIENCE ON THE LIVING STANDARDS IN VILNIUS CITY 

Daiva Griskeviciene

Vilnius Gediminas Technical University
Transport Management Department
Plytines str. 27, Vilnius, LT-10105, Lithuania
Ph: +370 5 2745099.
Fax: +370 5 2699714.
E-mail: griskeviciene.daiva@gmail.com

Good quality of life depends on a whole series of factors, including having enough money and dwelling with good communication conditions. The level of usage of public transport practically depends on both the level of system’s development accessible for all passengers and the level of citizen living standards, their lifestyle and financial possibilities. The regular route public transport system has serious competition from the side of private transport means in Lithuania. Selective data interrogation of Vilnius citizens seeking to explain their socio-economic possibilities to use public transport services or private cars was accomplished in 2007. The survey results show, that the main factor for the choice of public transport service is the purchasing power or life quality level of urban residents, and, on other hand, combination of the public transport service with the usage of private car for the sustainable development of communication systems in urban and suburb territories.
Keywords: public transport system, car competition, passenger market, living standards, expenses of household member, demand of suburban passengers

THE ANALYSIS OF THE CONSTRUCTION COSTS OF TRANSPORT INFRASTRUCTURE PROJECTS 

Аlgirdas Griskevicius1, Ausrine Griskeviciute-Geciene2

1Vilnius Gediminas Technical University
Transport Management Department
Plytines str. 27, Vilnius, LT-10105, Lithuania
Ph: +370 52745099.
E-mail: algirdas.griskevicius@gmail.com

2Urban Engineering Department
Saulėtekio al. 11, Vilnius,LT-10223, Lithuania
Ph: +370 52744719.
E-mail: aushgri@yahoo.com

The significant rise of the construction costs of transport investment projects at present days is considered in the paper. The analysis of reasons of cost rise is accomplished on the purpose to use the EU financial support and other financing resources for transport sector more effectively and to plan the further usage of investments for transport infrastructure. Costs, acting factors, financing resources influence on the priority projects of transport infrastructure are analysed and changes of construction costs are defined and the problems of the implementation of infrastructure project are clarified. The recommendations are offered concerning preventive measures for up the costs of transport infrastructure works and their application possibilities, and to substantiate the development of infrastructure projects.
Keywords: transport infrastructure projects, financing resources, the evaluation of investment projects, construction costs, influence of external factors

ANALYSIS OF THE QUALITY OF SERVICE OF THE RIGA COACH TERMINAL FROM THE VIEWPOINT OF TRAVELLERS 

Vaira Gromule

JSC Riga International Coach Terminal
Pragas str. 1, Riga, LV-1050, Latvia
E-mai: autoosta@autoosta.lv

In this research the main attention is paid to the analysis of the reasons – why travellers choose train rather than bus in some regional directions in Latvia. This analysis is done on the basis of the results of questionnaire and in future it may be the basis for the Discrete-Choice models application. Also the analysis of the travellers’ attitude to service of the Riga Coach Terminal is fulfilled on the basis of the annual questionnaire data.
Keywords: coach terminal, passengers, service quality, transportation, transit capacity

MODELLING AND FORECASTING OF GREENHOUSE GASES EMISSION IN LATVIA 

Mara Gulbe1, Arnis Gulbis2

1University of Latvia
Faculty of Economics and Management
Aspazijas blvd. 5, LV-1050, Riga, Latvia
Ph: +371 67034746.
E-mail: mgulbe@lanet.lv

2Riga Technical University
Faculty of Electronics and Telecommunications
Azenes str. 12, LV 1048, Riga, Latvia
Ph: +371 67089239.
E-mail: Arnis.Gulbis@etf.rtu.lv

This paper presents a forecast analysis of production in different sectors of Latvia’s manufacturing. It considers the results of investigation ordered by Ministry of Environment Protection. The forecasts of production growth in different sectors of manufacturing are calculated up to 2020. On basis of these forecasts by means of unified EU methodology the forecasts of CO2 emission are calculated. The calculated CO2 emission forecasts will serve for Latvia’s emission quota demand from EU as basis.
Keywords: "Greenhouse effect", greenhouse gases, CO2 emission, production functions

IMPROVEMENT OF URBAN TRANSPORT ACCESSIBILITY FOR THE PASSENGERS WITH REDUCED MOBILITY BY APPLYING INTELLIGENT TRANSPORT SYSTEMS AND SERVICES 

Gražvydas Jakubauskas

Vilnius Gediminas
Technical University Faculty of Transport Engineering
Transport Management Department
Plytinės str. 27, Vilnius, LT-10105, Lithuania
Ph: +370 52745099.
Fax: +370 52745059.
E-mail: Grazvydas.Jakubauskas@ti.vgtu.lt

Deployment of Intelligent Transport Systems and Services (ITS) has been strongly considered as crucial element of improved accessibility for passengers with reduced mobility. Intelligent transport systems in the light of improving an access to urban transport for passengers with reduced mobility are analysed in the article. The need of deployment of these systems in three areas – information, infrastructure and vehicles is emphasized and practical examples are provided. Only in the case if intelligent transport systems are deployed in all the three areas, a seamless transportation for the disabled people is ensured. The aim of the research is to evaluate solutions, encouraged by the EU transport policy and proved by a good practise that might be implemented in Lithuanian urban transport system. These solutions are also based on results of questionnaire, accomplished by the author.
Keywords: mobility handicaps, reduced mobility, sustainability, Intelligent Transport Systems

ESTIMATION OF IMPORTANCE OF INTELLIGENT TRANSPORT SYSTEMS (ITS) ARCHITECTURE 

Aldona Jarasuniene

Transport Research Institute
Vilnius Gediminas Technical University,
Plytines str. 27, LT-10105, Vilnius-16, Lithuania
Ph: +370 2745076,
fax: +370 2699711
E-mail: ajarasuniene@yahoo.com

This paper introduces the important concepts of system architecture, including why it is needed and how it has been developed and applied around the word. In the past, control systems for road traffic were often installed to provide just one or two services working independently as separate subsystems, In contrast, complex management, control and data-gathering services are provided simultaneously by ITS. While there are risks of a number of subsystems working in conflict with one another, there are significant opportunities for an amalgamation of these subsystems working in synergy. System architecture provides the logical framework, based on user requirements for planning, defining, and integrating intelligent transportation systems. A national or regional system architecture is a formal statement of the national or regional approach to ITS, and the first step on the way to creating detailed designs. In addition, the establishment and use of the ITS architecture adds considerable value to the overall ITS development process in various ways.
Keywords: ITS Architecture, shared vision, risk management, levels of ITS Architecture

THE FEASIBILITY STUDY TO TRANSFER GOODS BETWEEN PORTS OF KLAIPEDA AND SWINOUJUSCE 

Ilona Jaržemskienė1, Jurgita Barysienė2, Vytautas Jaržemskis3, Andrius Jaržemskis4

Vilnius Gediminas Technical University
Sauletekio av. 11, Vilnius-16, LT-10105, Lithuania
Ph.: +370 52370605.
Fax: +370 52370555
E-mail: 1ilona@ti.vgtu.lt,
2bjurgita@ti.vgtu.lt,
3vytautas.jarzemskis@ti.vgtu.lt,
4andrius.jaržemskis@ti.vgtu.lt

The purpose of this article is to present results of the research of feasibilities of freight transportation by ferry between Klaipeda Seaport in Lithuania and Swinoujusce Seaport in Poland. The study is related to the BSR Interreg III B NP project Baltic Gateway PLUS. The study includes the following researches: (1) to specify freight flows to Region Berlin via Klaipeda Seaport; (2) to specify freight flows to Region Berlin via Kalvariju cross border check point. The applied method is the collection of official statistical data for years 2005 and 2006 from legal statistical bureaus and some freight operators. The study concluded that freight flow via Klaipeda port and Kalvariju check point (incl. Lazdiju) to the so-called Region Berlin defined as the destination point in which freight was unloaded was 199,59 thousand tons in 2005 and 229,96 thousand tons in 2006. Freight flow via Klaipeda port and Kalvariju check point (incl. Lazdiju) from the so-called Region Berlin defined as origin point in which freight was loaded was 48,88 thousand tons in 2005 and 78,45 thousand tons in 2006. About 10 % of freight flow in axis Kalvariju-Berlin is loaded/unloaded in the so-called Region Berlin. About 90 % of flow in the mentioned axe is a cross trade flow of Region Berlin.
Keywords: intermodal transport, transport statistics, short sea shipping, freight flows, trailer, ferry

RESEARCH OF TECHNOLOGY TRANSFER PROBLEMS IN LITHUANIA 

Andrius Jaržemskis1, Renatas Morkvėnas2, Vytautas Jaržemskis3, Mindaugas Samoška4

Vilnius Gediminas Technical University
Sauletekio av. 11, LT-10105, Vilnius-16, Lithuania
Ph: +370 52370605.
Fax: +370 52370555
E-mail: 1andrius.jarzemskis@ti.vgtu.lt;
2renatasmorkvenas@yahoo.com;
3vytautas.jarzemskis@ti.vgtu.lt

Lithuania has already become a real member of the European Union, where the priority and the aim are knowledge of economy and technology innovation policy. Lithuania is far away from the other EU countries and the other candidate countries developing technology knowledge together with entrepreneurship. So, this fact promotes the deeper analysis of technology environment as the anchor of technological innovations and encourages foreseeing its further development in Lithuanian. The promotion of innovation is implemented by developing business incubators, science and technology parks in Lithuania. Now Lithuania has 7 business incubators, 6 science and technology parks. Here the enterprises have administrative services, rending, and technical support on favourable terms.
Keywords: technology transfer, technology parks

VIDEO REGISTER PICTURE EVALUATION TO SUPPORT DRIVERS TRAINING AND EXAMINATION 

Tomasz Kamiński, Gabriel Nowacki, Izabella Mitraszewska

Motor Transport Institute
Management and transport telematics Centre
Jagiellońska 80, 03–301 Warsaw, Poland
Ph : +48 228113231 ex. 134
E-mail: tomasz.kaminski@its.waw.pl

This paper refers to some problems on digital video recording of picture during driver training and examination process for obtaining driving license. Since 10 April 2006, all examining institutions have to use video and audio recording devices in Poland. The legal regulations in force do not clearly determine the functional requirements and technical parameters for video recorders; hence the actual devices used do not meet user requirements. This paper describes a deterioration of recording quality parameters of the video recorder as well as construction of camera, its main elements and their influence on the recording quality parameters. The paper refers to attention to geometrical deformation of image that is made in optical camera system. The authors have made an attempt to determine camera parameters, their location and quality of the picture. In mentioned case the objective and subjective picture validation methods will be presented.
Keywords: video register, quality picture evaluation

DEVELOPMENT AT ACCIDENT FORECASTING METHODOLOGY IN ROAD TRAFFIC 

Denis Kapskij

Belorussian National Technical University
Nezavisimosty av. 65, Minsk, 220013, The Republic of Belarus
Ph.: +375 2312968.
Fax: +375 2373631.
E-mail: OAPDD@BNTU.BY

Keywords: losses in road traffic, methodology of accident forecasting, accident losses, social constituent, forecasting methods

MODELLING OF THE MULTIPRODUCT INVENTORY PROBLEM 

Eugene Kopytov1, Leonid Greenglaz2, Aivars Muravyov1

1Transport and Telecommunication Institute
Lomonosova str. 1, Riga, LV-1019, Latvia
E-mail: kopitov@tsi.lv, aivars@tsi.lv

2Riga International School of Economics and Business Administration
Meza str. 1, build. 2, Riga, LV-1048, Latvia
E-mail: gringlaz@riceba.lv

The given paper considers a multiproduct inventory control model with random demands for goods. The authors propose the model with a fixed period of time between the moments of placing neighbouring orders. The order quantity is determined as the difference between the fixed stock level and the quantity of goods at the moment of ordering. It is assumed that each order may enclose only fixed kinds of products. The considered model is realized by the combination of the analytical and simulation approaches in packages MS Excel and ExtendSim correspondingly. The numerical example of the problem solving is presented. The considered model is of interest because it illustrates a real business situation.
Keywords: inventory control, random demand, analytical method, optimisation, simulation

RECONSTRUCTION OF THE ROADWAY COVERAGE PARAMETERS FROM RADAR SUBSURFACE PROBING DATA 

Alexander Krainyukov, Valery Kutev, Daniil Opolchenov

Transport and Telecommunications Institute
Lomonosova str. 1, Riga, LV-1019, Latvia
Ph: +371 67100634,
fax: +371 67100660,
e-mail: krain@tsi.lv, kutev@tsi.lv, Opolo84@mail.ru

This work is focused on the development of approach to the inverse problem of subsurface radar sounding solution in frequency domain. The genetic algorithm is used for search of global minimum of aim functional. To improve accuracy of parameters reconstruction with the use of genetic algorithm it is necessary correctly to choose the values of arguments for aim function and parameters of genetic algorithm. We propose value of threshold in aim functional was set with the use of middle power of spectral constituents, used for the calculation of aim functional. Conditions are certain numeral calculations for the automatic calculation of threshold value Reconstruction of parameters for model roadway coverage is executed with the use of different of selection methods of genetic algorithm. Statistical estimations of the reconstruction of parameters under various conditions are received.
Keywords: radar, radar monitoring, inverse problem, genetic algorithm, reconstruction of parameters

ANALYSIS OF SOLITARY ELECTROMAGNETIC TRANSIENTS BASED ON THE K/E PULSE CONCEPT 

Yuri A. Krasnitsky

Transport and Telecommunication Institute
Lomonosov str. 1, Riga, LV-1019, Latvia
Ph.: +371 7100608.
Fax: +371 7100660.
E-mail: krasn@tsi.lv

Application of kill-pulse and extinction-pulse concepts for natural resonanses analysis of solitary electromagnetic pulses are discussed. The main problems considered are: 1) choice of the initial moment to extract the late time part of the pulse; 2) separation of natural resonances originating from the source of pulse radiation from the poles correlating with the propagation trace. For the purpose of illustrating the use of the poles extraction procedures for solitary non-repeated pulses generated by lightning discharges the set of Matlab programs was created. Some algorithms for the analysis of pulses registrated on different distances from lightning strokes are described. Efforts to evaluate irregularities in processed signals are demonstrated.
Keywords: convolutional model, natural resonances, poles estimation

STATISTICAL ANALYSIS OF IT SERVICE DESK INCIDENTS WITH OBJECTIVE TARGET FOR OPTIMISATION OF SERVICE LEVEL AGREEMENTS 

Jörg Kundler

Transport and Telecommunication Institute
Head of IT-Services, DFS, Deutsche Flugsicherung GmbH, Langen,
Am DFS-Campus 7, D-63225 Langen
Ph. +49 6103 707 2530.
Fax +49 6103 707 4596.
E-mail: Joerg.Kundler@dfs.de

Since year 2004 an in-sourced IT Service Desk of German Air Navigation Service is operated based on the Single Point of Contact (SPOC) to the customer of the German wide used Business Support Systems and ATM-shore Applications. The IT Service Desk operation is managed and controlled by Key Performance Indicators (KPI); because the insourcing project have been performed under the condition that the service is delivered at market conform conditions. Main parameters of SLA are based on arithmetic mean values. During review process of actual SLA parameter and customer pitches different lacks of calculation of service parameter have been detected. For a better evaluation of service quality it was decided to change arithmetic mean values for service parameter, due to the fact that arithmetic means stretch and “dilute” the different contents of service parameter. Average values for performance information are not sufficient for the service management. With help of quantiles it will be possible to fulfil the defined limits for different parameter ranges, especially for time and performance related parameter for the IT-Service desk. So it will be a better way to define quantified and differentiated service statements based on specified quantile Qp. The goal of statistical analysis is to investigate the observed service parameters and different technical analyses of serviced applications to derive technical expertise for an implementation of statistical quantiles as a basis function for service parameters. The results of statistical analysis of Service Desk Incidents is to be able to offer the mentioned KPIs by different requested quantiles for the SLA and to be able to offer these KPIs on higher scientific level. The results of statistical investigation will also be used for a more stabile forecasting and annual planning of service capacity and resources. The quantile distribution can be used for the incident distribution of service desk portfolio. So it can be decided that product releases shall switch into operation only by fulfilment of specified quantile Qp. In the paper typical and market conform service parameters for an IT Service Desk have been researched and the results of statistical analysis will be applied for further restructuring at operational use and adaptation of SLA.
Keywords: technical statistical analysis, categorization IT incidents, impact on SLA, service availability, service quantiles

ESTMATION OF RISK INSURANCE IN PRACTICE OF WORK OF ACTUARIALS 

Victor Lyumkis, Aleksei Tarasov

Transport and communication institute
Lomonosova str. 1, Riga, LV-1019, Latvia
E-mail: vlyumkis@yahoo.com, aleksejs@etalogic.com

The problem of estimating various probabilistic characteristics of risk in activity of actuaries of the insurance company is considered in the article. The model of collective risk is discussed more detail. As well as in models of individual risk, in models of collective risk ruin is defined by total payments S of the insurance company of kind S= Y1 + Y2 + Y3 + … + Yν, and the probability of ruin of the company are defined as P (Y1 + Y2 + Y3 + … + Yν > U), where U - size of actives of the company. Exact analytical estimation of this probability for any distributions of random variables ν and Yν are far not always possible to receive. In the article it is offered and numerically realized the algorithm of an estimation of probability of ruin of the insurance company under conditions of model of collective risk at use practically any distribution of size of damage and trivial discrete (non-negative integer) distribution of the number of insurance cases.
Keywords: statistics, insurance, estimation, collective risk model

PROFESSIONAL DRIVER’S LABOUR MARKET IN POLAND ACCORDING TO DIRECTIVE 2003/59 

Izabella Mitraszewska, Gabriel Nowacki, Tomasz Kamiński

Motor Transport Institute
Management and Transport Telematics Centre
Jagiellońska 80, 03–301 Warsaw, Poland
E-mail: izabella.mitraszewska@its.waw.pl

Significant changes can be observed on the professional driver’s labor market in Poland brought about by several reasons. First of all, there is a constant migration of the Polish drivers to the “old” EU countries and changes of the driving time requirements as well as resting time of the drivers, introduced by the Regulation 561/2006. The consequences of that are staff shortages in this professional group. The article discusses professional driver’s labour market segment, and estimates the number of drivers necessary to current conduct haulage tasks in the forthcoming years. Also taken into account are the needs of the commercial transport, whose share in the total haulage, despite the slumping tendencies, is still significant. There is an attempt to estimate the needs of the professional driver’s market in Poland. Finally, the results of the 2003/59 Directive implementation in Poland have been mentioned. It concerns preliminary and periodical training of the professional drivers and is due to come into force in September 2008.
Keywords: professional drivers, job market, average employment, multi-shift work system

SIMULATION OF INTELLECTUAL COMPUTER SYSTEMS OF PROCESSING MEDIA DATA 

Ravil Muhamediyev, Yury Shunin, Victor Gopeyenko

Information Systems Management Institute
Department of Natural Sciences and Computer Technologies
E-mail: ravil@inbox.lv, shunin@isma.lv, Viktors.Gopejenko@isma.lv

The problems of observing system’s simulation (a media dots in wide view) are considered. A classification of systems of video observation, base function of such systems and processes of analysing media dates are described. The approach to the analysing of video observation systems is proposed. Some simulation models based on stochastic Petri nets and results are discussed Now in all spheres of living systems of video observation and other media systems are actively applied. They allow conducting round-the-clock supervision over object, to supervise access, to operate technical devices remotely, to fix emergencies and to inform secure structures, so to provide safety and safety of people and material assets. The main source of the information in such systems is video stream, but not only this one. The various media-information sources can be generalized, using media-dots concept - an elements, which are capable to accept, reproduce and process media data. Much plenty of resources (memory and computing capacities) is required for processing and storing of media data. One of the problems is how to find optimum for using resources (processors, memory) so that there was the least number of refusals for the information processing. One of variants of the decision of this problem is the maximal processing of video information in the point of its reception.
Keywords: video observation, Petri nets, simulation model, media dots, program agents

OPTIMAL ADAPTIVE CONTROL OF PREVENTIVE MAINTENANCE PROCESS OF AIRCRAFT STRUCTURES 

Konstantin N. Nechval1, Nicholas A. Nechval2, Gundars Berzins2, Maris Purgailis2, Juris Krasts2, Uldis Rozevskis2, Kristine Rozite2, Vladimir F. Strelchonok3

1Transport and Telecommunication Institute
Department of Mathematical Methods and Modelling
Lomonosov Str. 1, LV-1019, Riga, Latvia
E-mail: konstan@tsi.lv

2University of Latvia
Mathematical Statistics Department
Raina Blvd 19, LV-1050, Riga, Latvia
E-mail: nechval@junik.lv

3Baltic International Academy
Informatics Department
Lomonosov Str. 4, LV-1019, Riga, Latvia
E-mail: str@apollo.lv

Fatigue is one of the most important problems of aircraft arising from their nature as multiple-component structures, subjected to random dynamic loads. Fatigue damage is considered to initiate in a structural element when cracks develop, whether or not they are detected. The fatigue process then continues by crack propagation, resulting in strength degradation. Periodic inspections of aircraft are common practice in order to maintain their reliability above a desired minimum level. Thus, a catastrophic accident during flight can be avoided. In this paper, a control theory is used for planning inspections in service of fatigue-sensitive aircraft structure components under crack propagation. One of the most important features of control theory is its great generality, enabling one to analyse diverse systems within one unified framework. A key idea, which has emerged from this study, is the necessity of viewing the process of planning in-service inspections as an adaptive control process. Adaptation means the ability of self-modification and self-adjustment in accordance with varying conditions of environment. The adaptive control of preventive maintenance process of aircraft structures differs from ordinary stochastic control of preventive maintenance process in that it attempts to re-evaluate itself by force of uncertainties in the preventive maintenance process as they unfold and change.
Keywords: aircraft, fatigue crack, preventive maintenance process, adaptive control

FINDING OPTIMAL MULTI-PERIOD PROJECT PORTFOLIO INVESTMENT STRATEGY UNDER UNCERTAINTY 

Konstantin N. Nechval1, Nicholas A. Nechval2, Gundars Berzins2, Maris Purgailis2, Juris Krasts2, Uldis Rozevskis2, Vladimir F. Strelchonok3, Natalie Zolova2

1Transport and Telecommunication Institute
Department of Mathematical Methods and Modelling
Lomonosova Str. 1, LV-1019, Riga, Latvia
E-mail: konstan@tsi.lv

2University of Latvia
Mathematical Statistics Department
Raina Blvd. 19, LV-1050, Riga, Latvia
E-mail: nechval@junik.lv

3Baltic International Academy
Informatics Department
Lomonosova Str. 4, LV-1019, Riga, Latvia
E-mail: str@apollo.lv

Project portfolio selection is a crucial decision in many organizations, which must make informed decisions on investment, where the appropriate distribution of investment is complex, due to varying levels of risk, resource requirements, and interaction among the proposed projects. In this paper, we present a mathematical model of investment for a set of projects under conditions of uncertainty. The model addresses the problem of an investor with access to a limited pool of capital, which makes decisions on investments. The problem is to decide how much to invest in each project so as to maximize the total expected return by the end of the horizon in relation to a given utility function. We discuss optimal investment decisions for the cases where the return from investment is a random variable. The single-period and multi-period cases of investment decisions are considered. The paper presents closed form solutions for commonly adopted utility functions.
Keywords: project, portfolio, multi-period investment, optimal control

CASCO INSURANCE STATISTICS AND INSURER’S RISK MANAGEMENT 

Nadezhda Novozhilova

Baltic International Academy
Lomonosov str. 4, LV-1019, Riga, Latvia
Ph: +371 294184876.
E-mail: elpis@btv.lv

A complex of the expert researches and actuarial accountings directed to the analysis of the transactions of CASCO insurance in the Latvian insurance market is performed in the given paper. Opportunities of creating the uniform and general system of the insurance statistics indices taking into account all objectives and functions of CASCO insurance are considered. Such complex of researches and calculations is performed for the development of the underwriting management and underwriting risk management of the auto insurance. The statistical data of the Financial and Capital Market Commission related to the insurance market in Latvia is used.
Keywords: CASCO insurance, uniform indices, statistics, risk management

RESEARCH OF INFRASOUND NOISE IN HEAVY GOODS VEHICLE AND BUSSES 

Gabriel Nowacki, Izabella Mitraszewska, Tomasz Kamiński, Andrzej Wierzejski

Motor Transport Institute
Management and Transport Telematics Centre
Jagiellońska 80, 03–301 Warsaw, Poland
Ph: +48 228113231 ex. 134
E-mail: gabriel.nowacki@its.waw.pl

The article refers to some problems of infrasound and infrasound noise and their influence on the behaviour of drivers of mechanical vehicles and machine operators. Infrasound waves act on the entire human organism. They induce resonance vibrations of the chest, abdominal membrane and digestive organs. That causes respiratory system problems, and with a prolonged exposure leads to the digestive system disorders. Furthermore infrasound causes feeling of tiredness, discomfort, and drowsiness; it decreases psychomotoric perception and eye sight clarity. Motor Transport Institute has carried out research on infrasound noise. Measurements were taken using SVANTEK SVAN 945A register on correction curves A, Lin and G as well as dynamic characteristics Fast and Slow. Measurements were made only in the driver work place, recording level of sound pressure for 30 seconds. Tests were carried out on 5 buses (M3 category), 10 vehicles of N3 category (saddle tractors and HGV`s), 3 HGV`s N1 category and 2 vehicles of category M1. Research results confirm high infrasound noise levels in the case of M3 category vehicles. They would remain at about 110÷115 dB level, according to correction curve G with relatively low level of interior noise of about 66÷74 dB according to correction curve A, and at the speed range of 70 to 90 km/h. The level of infrasound noise reaches lower values of about 100 dB in the vehicles of N3 and N1 category. During the research, an importance of road surface condition was established, adding up to 7 dB, but in extreme cases even up to 10 dB, causing momentary increase of infrasound noise even to 125 dB.
Keywords: infrasound, infrasound noise

ANALYSIS OF TRANSPORT TERMINALS NETWORK STRATEGIC PLANNING 

Ramunas Palsaitis, Gintautas Labanauskas

Vilnius Gediminas Technical University
Department of Transport Management
Plytines str. 27, Vilnius-16, LT-10105, Lithuania
Ph: +370 852744776.
Fax: +370 852745059.
E-mail: trvadyba@ti.vgtu.lt

Creation of the network of transport terminals in Lithuania will have a positive impact on the economical development of the country. Transport terminals located in the strategic dominant state points and established under the contemporary requirements will provide the needed co-operation with big trading companies and other terminals in the EU, Europe and outside Europe. The existing TEN-T corridors will play significant role in interlinking separate terminals into the international network. An increase of international transit cargo flows will be also related to the complementary and boosting activities of logistic services associated with the development of transport terminals network as in Lithuania as in the whole region.
Keywords: terminals, logistics, transport, economics, development, cargo

BAYES-FIDUCIAL APPROACH FOR MATHEMATICAL STATISTICS PROBLEM SOLUTION 

Yury Paramonov

Aviation Institute
Riga Technical University
Lomonosova str. 1, Riga LV 1019, Latvia
Ph.: +371 7255394;
fax: +371 7089990;
E-mail rauprm@junik.lv

Review of using of Bayes-Fiducial (BF) approach for solution of some important statistical problem is given. BF decision is always a function of sufficient statistics (even in case when sufficient statistics coincides with the sample itself (for example, for Weibull distribution)). By contrast with maximum likelihood method BF decision is based on the use of specific loss function. By contrast with Bayes decision it does not need a priori distribution of unknown parameters. For the distributions with location and/or scale parameter the solutions of the following problems are considered: point estimates of location and scale parameters, p-bound (prediction limit) calculation and specified life nomination with specific loss function. Numerical examples are given.
Keywords: parameter estimation, testing statistical hypotheses, prediction limit

EFFICIENCY ANALYSIS OF EUROPEAN COUNTRIES RAILWAYS 

Dmitry Pavlyuk

Transport and Telecommunication Institute
Lomonosova str. 1, Riga, LV-1019, Latvia
Ph: +371 29958338.
Email: dmitry@magicwebsolutions.co.uk

This study uses stochastic frontier analysis for estimating efficiencies of railways systems in European countries. We consider railways as a system which uses its infrastructure (length of lines worked, numbers of cars and wagons, staff strength) and a scale of market (number of habitants and tourists) for transporting passengers and freights. We estimate efficiencies of freight and passenger transportations separately on the base of different models. We use the database provided by International Union of Railways, which includes annual statistical data about biggest European railways companies from 1997 to 2006 to estimate model parameters. Railways systems show huge variations in technical efficiency between different countries and also between freight and passenger transportation within the same country. The study also contains the analysis of dependencies between calculated railways efficiency estimates and popular economic indicators.
Keywords: stochastic frontier, efficiency, railway systems

A DISCRETE CHOICE MODEL FOR WEB SITE WORK RESULTS 

Dmitry Pavlyuk

Transport and Telecommunication Institute
Lomonosova str. 1, Riga, LV-1019, Latvia
Ph: +371 29958338.
Email: dmitry@magicwebsolutions.co.uk

Currently a corporate web site is not considered as a necessary business attribute, but as a marketing tool which should yield results. In this study we consider a web site as an instrument for attraction of new partners (customers, suppliers). Web site outputs are a number of visitors interested in contact information (reached the contact info page) and a number of visitors who sent a request via a special form on the web site. We build a sequential discrete choice model for web site outputs. Explanatory variables set includes a number of visited pages, seconds spent on the web site, and dummy variables for specific pages visited (a page with prices information, a portfolio page). Also we investigate an influence of search engines (Google, Yahoo, MSN), which refer a visitor to a corporate web site and keywords used for pay-per-click advertising campaigns. We estimate model parameters on the base of a small UK-based web development company’s web site statistical data and discover strong dependencies, which allow improving web site organisation and its search engine positioning.
Keywords: sequential discrete choice model, corporate web site

THE ECONOMETRIC ANALYSIS OF THE MUSEUM AUDIENCE IN POLAND 

Mariola Piłatowska, Aleksandra Mreła, Anna Pomianowska-Kardaś, Danuta Nowicka

Wyższa Szkoła Gospodarki w Bydgoszczy
Garbary 2-3, 85-229 Bydgoszcz, Poland
Ph: (4852)5670047.
E-mail: mpilat@umk.pl, amrela@byd.pl,
annapomianowska@byd.pl, danowicka@o2.pl

Analysing the tourist attractions the role of museums is of great importance. To study the museum attractiveness the questionnaire surveys are often conducted with focus on recognition of visitors and factors influencing the reception of the museum exhibitions. However there are also quantitative measures of museum attractiveness like the museum audience. The purpose of the paper is to analyse the museum audience in Poland (on the example of chosen museums), to forecast it and to indicate the perspectives of development in museum tourism.
Keywords: tourism, econometric analysis, museum audience

INVESTIGATION OF TRAFFIC ACCIDENT: GATE DEFORMATIONS DURING MOTOR VEHICLE-GATE INTERACTION 

Olegas Prentkovskis1, Andrey Beljatynskij2, Rasa Prentkovskienė3, Ona Lukoševičienė4, Edgar Sokolovskij5

1, 3, 4, 5Vilnius Gediminas Technical University
Faculty of Transport Engineering

1, 3Dept of Transport Technological Equipment
Plytinės g. 27, LT-10105 Vilnius, Lithuania

4, 5Dept of Automobile Transport
J. Basanavičiaus g. 28, LT-03224 Vilnius, Lithuania

2National Aviation University
Institute of Municipal Activity
Dept of Airport Reconstruction and Automobile Roads
Kosmonavta Komarova ave 1, 03680 Kiev, Ukraine

E-mails: 1olegas@ti.vgtu.lt; 2beljatynskij@mail.ru; 3rasa@ti.vgtu.lt; 4tiauto@ti.vgtu.lt; 5edgar.sokolovskij@ti.vgtu.lt

Statistical data of registered traffic accidents in Lithuania is presented. The specific traffic accident investigated using the mathematical model of transport and pedestrian traffic restricting gate which is designed and briefly presented in paper. There are two sections of the gate: first section restricted the traffic of motor vehicles, second section limited the traffic of pedestrians. The gate was modelled based on the first-order one-dimensional finite elements taking into account only the resilience of the gate elements and the impact of soil on the ground-embedded parts of the gate support and auxiliary posts. The deformations of gate elements were determined based on the mathematical model designed. The computer-run simulation (for the purpose of working out the mathematical model of gate) was performed using specially developed Maple and Compaq Visual Fortran Professional software-based applied programs.
Keywords: traffic accident, motor vehicle, interaction, gate, finite elements, deformation, computer-run simulation

POPULARITY OF STUDY PROGRAMMES IN TRANSPORT MANAGEMENT AMONG THE APPLICANTS TO LITHUANIAN HIGHER SCHOOLS, PARTICIPATING IN JOINT ADMISSION PROGRAMME 

Olegas Prentkovskis1, Romualdas Kliukas2, Alfonsas Daniūnas3

Vilnius Gediminas Technical University
Admission Office of Applicants
1Plytinės g. 27, LT-10105 Vilnius, Lithuania
E-mail: olegas@ti.vgtu.lt

2Saulėtekio al. 11, LT-10223 Vilnius, Lithuania
E-mail: pirmininkas@adm.vgtu.lt

3Saulėtekio al. 11, LT-10223 Vilnius, Lithuania
E-mail: alfonsas.daniunas@adm.vgtu.lt

The operation of industrial, construction and agricultural enterprises as well as work efficiency and public opinion largely depend on reliability and effective performance of transport system. Lithuanian universities train qualified specialists in transport management, who are highly appraised in the European Union and other countries. Two higher schools in Lithuania (Vilnius Gediminas Technical University and General Jonas Žemaitis Military Academy of Lithuania) offer study programmes in transport management, leading to Bachelor’s degree in Management and Business Administration. The present paper briefly describes a system of joint admission to Lithuanian higher schools which has been already used for several years in Lithuania. The problems of selecting applicants to Lithuanian universities and the level of knowledge of the applicants admitted to study the programmes in transport management will also be discussed.
Keywords: Lithuanian universities, applicants, joint admission, transport management, study programme, popularity

EFFECT OF WIND CONDITIONS OF SITE LOCATIONS OF WIND TURBINE GENERATORS CAUSED ON PROFITABILITY OF THE COMMERCIAL WIND ENERGY PROJECTS 

Jurijs Roļiks

Transport and Telecommunication Institute
Lomonosova str. 1, Riga, LV-1019, Latvia
Ph: +371 67100585,
e-mail: rolik@tsi.lv

Hereby the results of operation of two wind energy projects realized on the basis of the wind turbine generators (WTG) of the NORDEX N54 type of the 1.0 MW capacity each, in the localities of Uzhava and Alsunga at the Baltic sea coast of the Republic of Latvia, over the 5-year period are presented. The results were obtained by means of comparison of the wind conditions and basic economic indexes of operation of the WTG’s of the considered projects. It demonstrates the effect of wind conditions and distance of the WTG site locations from the coastline caused on the profitability of the commercial wind energy projects.
Keywords: wind turbine generator, wind conditions, wind speed, annual electric energy production, prime cost of 1 kWh of electric energy

OVERVIEW OF FLOW SYSTEMS INVESTIGATION AND ANALYSIS METHODS 

Mihail Savrasov

Transport and Telecommunication Institute
Lomonosov str. 1, Riga, LV-1019, Latvia
Ph.: +371 29654003,
e-mail: mms@tsi.lv

This paper presents the results of the overview of flow systems research methods and approaches. Under the flow systems it could be understood the artificial, technical and controlled systems created for material and non-material objects processing (generation transportation, transformation, accumulation and termination). The set of objects could be fixed by direct measurement or could be presented conceptually in separate system points (on the network links). They are presented as the sequences of discrete batches or as the continuous flow. Flow systems cover not only different systems of the material flow processing but also the systems themselves, the financial and tasks flows are processed, for example. For this moment there are a lot of methods, which could be used for the flow systems research. The classification of methods is presented. The classification on the high level contains: the analytical modeling and simulation. Under analytical modeling there is shown a wide range of methods and theories. The simulation branch is presented by three approaches. They are the simulation on microscopic level, simulation on mesoscopic level and simulation on macroscopic level. The advantages and disadvantages of using every approach are described here.
Keywords: flow system, modeling, flow systems investigation

MODELLING OF FUNDAMENTAL PROPERTIES OF CARBON NANOTUBES 

Yury Shunin, Victor Gopeyenko

Information Systems Management Institute
Department of Natural Sciences and Computer Technologies
E-mail: shunin@isma.lv, Viktors.Gopejenko@isma.lv

The scattering theory approach gives possibilities to calculate an electronic structure and elastic properties of condensed media, which should be considered as static phenomena. At the same time this approach is convenient for the electron transport modelling, which is a dynamical problem. It is the principal distinctive feature as compared to a tight-binding theory, where transport phenomena defy description. Some special problems of multiple scattering theory approach for effective media electronic structure calculations of carbon nanotubes, which are considered as perspective elements of nanodevices for computer technologies are studied.
Keywords: multiple scattering theory, carbon nanotubes

REDUCING EMPTY CONTAINER FLOW BY PROMOTING BALTIC AND RUSSIAN’S WASTEPAPER EXPORT TO CHINA THROUGH PORT OF TALLINN 

Andres Tolli1, Hanh Dam Le-Griffin2

1Institute of Roads Tallinn
University of Technology
19086 Tallinn, Estonia
Ph.: +372 6770391.
Fax +372 6202601.
E-mail: andres.tolli@live.com

2Department of Civil and Environmental Engineering
University of Southern California
CA 90089, Los Angeles, USA
Ph.: +1 2137400603.
Fax +1 213-740-8662.
E-mail: hdle@usc.edu

In 2006 out of one hundred imported marine containers from China to Europe, forty one were repositioned to China empty and from Russia at least seventy. To promote a healthy trade between these countries, it requires a more balanced cargo flows. It is of high importance that the marine containers filled with commodities sent from China to the Baltics and Russia would not be transported back to China empty. This paper provides a global analysis on freight flows by commodity to and from China with focus on a comparative analysis of potential export cargo to China. Our goal is to explore the possibility and to propose a logistics mechanism to promote the growth of container trade between China and Russia via Estonia. In developing our analysis, wastepaper is considered in this paper as one of the potential export commodities from Russia and Baltics through Estonia to China. The potential of this commodity to fill containers that would otherwise be repositioned empty to China, and the possibility of consolidating empty containers at the Port of Tallinn from other trade flows with China, is examined.
Keywords: Wastepaper, container, export, market, trade, port

TRANSPORT SYSTEM’S MESOSCOPIC MODEL VALIDATION USING SIMULATION ON MICROLEVEL 

Jury Tolujew1,2, Mihail Savrasov1

1Transport and Telecommunication Institute
Lomonosova 1, Riga, LV-1019, Latvia
Ph: +371 29654003.
E-mail: mms@tsi.lv

2Otto von Guericke University Magdeburg
Universitätsplatz 2, Magdeburg, 39106, Germany
Ph: +49391 4090310.
E-mail: tolujew@iff.fraunhofer.de

A lot of new mathematical models for traffic systems were developed in the past. Two approaches are widely used, namely microscopic and macroscopic models. Both approaches have several deficits. The mesoscopic approach presented here eliminates the deficits inherent in both the microscopic and the macroscopic approach [1]. The paper shows that the mesoscopic approach is suitable for reproducing process sequences in flow systems and describes the use of the mesoscopic approach to modelling and analysing a group of crossroads, which organizes transport network. There exist good results in modelling the particular crossroad, which could be found in [2]. But the task of modelling a transport network is still open. The paper presents the conceptual mesoscopic model of the defined transport network and its implementation with MS Excel plus VBA. The modelling task is to estimate the dynamics of all the queues and the crossroads capacity utilization. The mesoscopic approach is quite new; there is only one paper, which validates mesoscopic approach, done for queuing systems [3]. That is why the task of mesoscopic models validation is implemented. To validate mesoscopic model we are using simulation on microscopic level, by development of the model in simulation package PTV VISION VISSIM 5.1 [4], which is widely used for traffic simulation [5].
Keywords: mesoscopic modelling, crossroad modelling, crossroad capacity estimation, microsimulation

COVERAGE ENSURING IN HETEROGENEOUS WIRELESS NETWORKS 

Boris Tsilker

Transport and Telecommunication Institute
Faculty of Computer Science and Electronics
Lomonosova str. 1, Riga, LV-1019, Latvia
E-mail: tsilker@tsi.lv

Wireless network cost-effectiveness always is of primary importance regardless of network type. One of the feasible solution lies on the way of heterogeneous networks, consisting of different kinds of nodes with various coverage abilities. The high-end nodes have greater servicing range; the low-end ones are much cheaper and with lesser service radius. A mixed deployment of these nodes can achieve a balance of coverage and cost of wireless network. In any case necessary coverage level at every point in the service area must be ensured. Some aspects of suitable network topologies for such kind networks are discussed. It is noted that in most cases network cost-effectiveness improvement with ensured 1-coverage is reachable, replacing particular low-end nodes by high-end ones at saving existing node allocation. Possible approach for near to optimal choice of candidates for such replacement is proposed. The approach is based on the mathematical apparatus of Voronoi tessellation, namely on multiplicative weighted Voronoi diagrams, allowing to take into account heterogeneity of the network. Proposed method allows finding a good approximation for optimal cost-effective heterogeneous wireless network topology saving the desirable level of network area coverage.
Keywords: wireless networks, coverage, heterogeneity, homogeneity, Voronoi tessellations

KNOWLEDGE MANAGEMENT MODEL FOR CONSTRUCTION PROJECTS 

Laura Tupenaite, Loreta Kanapeckiene, Jurga Naimaviciene

Vilnius Gediminas Technical University
Sauletekio Avenue 11, Vilnius, LT-10223, Lithuania
E-mail: Laura.Tupenaite@adm.vgtu.lt

In the past there has been no structured approach to learning from construction projects once they are completed. At present the construction industry is adapting concepts of knowledge management to improve the situation. In this paper knowledge management benefits to construction industry organizations and projects are discussed. The main purpose of this paper is to present knowledge management model for construction projects. Paper consists of three parts. In the first part the concept of knowledge management in construction is discussed. In the second part different knowledge management models presented in scientific literature are discussed and compared as well as the new model, developed by the authors, is presented. In the third part, basing on the proposed model, the architecture of Knowledge Based Decision Support System for Construction Projects Management has been created as well as Multiply Criteria Analysis Method COPRAS application for construction decisions support have been discussed.
Keywords: knowledge management, construction projects, knowledge based decision support system, multiply criteria analysis

RISK LEVEL EVALUATION OF CONSTRUCTION INVESTMENTS PROJECTS 

Leonas Ustinovichius, Galina Shevchenko

Vilnius Gediminas Technical University
Civil Engineering Faculty
Department of Construction Technology and Management
Sauletekio av. 11, Vilnius, LT-2040, Lithuania
E-mail: Galina.Sevcenko@st.vgtu.lt

Management of investment risk is a usual practice of any investment project or business. The estimation of risk must be carried out at various project stages. In practice it is impossible to avoid not exhaustive and inaccurate information, therefore, unfavourable risky situations occur, the consequences of which can be very damaging to the project or business. Due to close cooperation of the participants of the project the risk occurring in one stage of the project can transfer to other stages and one type of risk can change into another one. This means that chain reaction is characteristic to the risk and it decreases efficiency and safety of any project or business. Various types of risk can be caused by different factors. Classification of risk is determined by efficiency of risk management organisation. Risk classification is understood as risk allotment according to certain features into concrete groups for reaching the set objectives. Conceptually reasoned risk classification allows defining the role of each risk in the total system of all risks. This paper presents methods of multiattribute comparativite analysis (CLARA and SAW methods) of variants of investment classified risks in construction. A practical case of illustrating the methods work is presented.
Keywords: investment, project, risk, multi-attribute analysis

USE OF STATISTICAL TECHNIQUES IN QUALITY MANAGEMENT SYSTEMS 

George Utekhin

Transport and Telecommunication Institute
Lomonosova str. 1, Riga, LV-1019, Latvia
Ph. +371 26516513,
e-mail: gu@tsi.lv

This article contains research results, what was made with a purpose to analyse statistical technique using in quality management practices. 34 enterprises and organizations have been analyzed. And a lot of problems in statistical technique using were identified.
Keywords: statistical techniques, quality management

SOME QUESTIONS OF SPEED HUMPS APPLICATION ON THE ROADS 

Yuri Vrubel, Denis Kapskij, Dmitrij Mazalevskij, Tatiana Samoylovich, Tonja Korzhova, Vasilij Kuzmenko

Belorussian National Technical University
Nezavisimosty avenue, 65, Minsk, 220013, The Republic of Belarus
Ph: +375 2312968.
Fax: +375 2373631.
E-mail: OAPDD@BNTU.BY

In the article questions of application of humps in streets and roads from the point of view of their effective application are considered. Efficiency of application should be estimated by losses in road traffic (emergency, ecological, economic and social). The analysis of results of preliminary researches is given.
Keywords: speed bump, losses in road traffic

FUTURE OF AIR-TRAFFIC-MANAGEMENT: HOW TO OVERCOME A POTENTIAL CAPACITY WALL? 

Peter Waldinger

DFS Deutsche Flugsicherung GmbH (1993-2007)
Technical University Darmstadt
Feldstraße 24 E, D-61352 Bad Homburg, Germany
Ph: +49 (0) 172 8473204.
E-mail: Peter@Peter-Waldinger.de

Punctuality, safety, sustainability and efficiency (user charges) are the key performance indicators of air traffic management. They are grounds for performance benchmarks, based on reporting systems and reliable statistics being more and more available. In particular punctuality was not satisfying in the last decade. The so-called “punctuality crisis” was the catalyst of the “Single European Sky” (SES) initiative and program, whose implementation we are experiencing now. The political objectives associated to SES are ambitious. Main programmatic parts to achieve these goals are the creation of “Functional Airspace Blocks” (FAB), the concept of “Flexible Use of Airspace” (FUA) and in particular the SESAR (SES ATM Research) Program plus the harmonization of processes, roles, structures and systems in the EU. In this paper the focus is on SESAR and the innovation it will bring to the European ATM network in terms of methods, operational concept and technology.
Keywords: statistics of punctuality, growth in aviation, capacity-limits, Single European Sky (SES), SES-ATM-Research (SESAR), innovation in air traffic management

SELECTION OF CONSTRUCTION PROJECT MANAGERS BY APPLYING COPRAS-G METHOD 

Edmundas Kazimieras Zavadskas1, Zenonas Turskis2, Jolanta Tamosaitiene3, Valerija Marina4

Vilnius Gediminas Technical University
1,2,3Departmen of Construction Technology and Management
4 Institute of Humanities,
Department of Foreign Languages
Sauletekio av. 11, LT-2040 Vilnius, Lithuania
E-mail: 1edmundas.zavadskas@adm.vgtu.lt; 2zenonas.turskis@st.vgtu.lt; 3jolanta.tamosaitiene@st.vgtu.lt; 4lynx_114@yahoo.com

There is a number of attributes and associated sub-factors influencing the matching of managers to construction projects. Attributes and sub-attributes were identified based on a thorough review of the related literature and interviews of management personnel involved in the selection of project managers. Project managers’ characteristics are considered to be less important for effective project management. The model is based on multi-attribute evaluation of project managers. The evaluation embraces the identified attributes influencing the process of construction project manager selection. This paper considers the application of grey relations methodology for defining the utility of alternatives, and a multiple criteria method of COmplex PRoportional ASsessment of alternatives with Grey relations (COPRAS-G) is offered. In this model, the parameters of the alternatives are determined by the grey relational grade and expressed in intervals. A case study presents the selection of construction project manager. The results obtained show that this method may be used as an effective decision aid in multi-attribute selection.
Keywords: COPRAS, grey relations, manager, selection

CONSTRUCTION RISK ASSESSMENT OF SMALL SCALE OBJECTS BY APPLYING TOPSIS METHOD WITH ATTRIBUTES VALUES DETERMINED AT INTERVALS 

Edmundas Kazimieras Zavadskas1, Zenonas Turskis2, Jolanta Tamosaitiene3

1, 2, 3Vilnius Gediminas Technical University
Civil Engineering Faculty,
Department of Construction Technology and Management
Sauletekio av. 11, LT-2040 Vilnius, Lithuania
E-mail: 1edmundas.zavadskas@adm.vgtu.lt; 2zenonas.turskis@st.vgtu.lt; 3jolanta.tamosaitiene@st.vgtu.lt

The paper presents risk assessment in construction. The assessment of small scale construction objects in competitive environment is based on the multi-attribute method. Ranking of objects and determination of their optimality are calculated by applying TOPSIS method with attributes values determined at intervals. The risk evaluation attributes are selected taking into consideration the interests and goals of the stakeholders as well as factors that have influence of the construction process efficiency. A background and a description of the proposed model are provided and key findings from the analysis are presented.
Keywords: TOPSIS attributes values determined at intervals, risk, assessment.

APPLICATION OF VERBAL METHODS TO MULTI-ATTRIBUTE COMPARATIVE ANALYSIS OF INVESTMENTS RISK ALTERNATIVES IN CONSTRUCTION 

Edmundas Kazimieras Zavadskas, Leonas Ustinovichius, Zenonas Turskis, Galina Shevchenko

Vilnius Gediminas Technical University
Civil Engineering Faculty
Department of Construction Technology and Management
Sauletekio av. 11, Vilnius, LT-2040, Lithuania
E-mail: Galina.Sevcenko@st.vgtu.lt

Management of investment risk is a usual practice of any investment project. The estimation of risk must be carried out at various project stages. Management of investments risk means presence of the all procedures control in any phase of the project. Quite reliable estimations of investments quality are a challenge because the uniform parameter of probability of means return does not exist yet. There is a set of attributes (parameters, factors, criteria) necessary for considering. The investor works conditions changes continuously due to an economic situation changes. The rules of an estimation of investment projects quality really can be based only on the politician of a management of the investor and lean on its intuition and experience. During decision-making becomes classification essential a role, i.e. the attitude of objects to classes of decisions. The classification subject objects can be described by means of various attributes estimations. The attributes can have both qualitative and quantitative character. At competent statement of investment process is in parallel used a method. There are known various methods of such problems decision. Verbal methods are applying in the given work for definition of investments risk in construction. The offered method of the best of building investment projects variants selection is tested in the decision of actual problem.
Keywords: investment, project, risk, the qualifier of attributes, multi-attribute analysis

STABILITY CONDITIONS FOR MARKED POINT PROCESSES WITH QUASITOEPLITZ SELECTED DISCRETE COMPONENT 

Andrei Zorine

Nizhniy Novgorod State University
603950, Russia, Nizhniy Novgorod, prospect Gagarina, 23
Department of Calculative Mathematics and Cybernetics
Ph: +7 831 4657883,
Email: zoav1@uic.nnov.ru

It is important for practical needs to discover conditions for existence of stationary distributions of queue length, waiting time and computation of different service characteristics for systems with unreliable server. Real-world flows of customers have varying stochastic structure which can be seen as a presence of some random environment. Marked point processes with selected discrete components arise as a natural mathematical model of unreliable service process in random environment. These selected discrete components have some general properties which help investigating stationarity conditions. Example application to a single-line system with unreliable server and non-ordinary input flow is considered.
Keywords: unreliable server, queuing system in random environment, stationary distribution, quasitoeplitz chains, iterative-dominating approach

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