2013, volume 14 #1. "Transport and Telecommunication". Журнал издательства TSI, ISSN 1407-6160, ISSN 1407-6179 | TSI

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2013, volume 14 #1. "Transport and Telecommunication". Журнал издательства TSI, ISSN 1407-6160, ISSN 1407-6179

 

EXPLORATORY ASSESSMENT OF THE LIMITING EXTENDED KALMAN FILTER PROPERTIES

Constantinos Antoniou, Alexandra Kondyli, Georgia-Maria Lykogianni and Elias Gyftodimos

National Technical University of Athens, Greece, School of Rural and Surveying Engineering
Laboratory of Transportation Engineering
Zografou, GR-15780, Greece
Ph.: +30 210 7722783. Fax: +30 210 7722629
E-mail: antoniou@central.ntua.gr, akondyli@gmail.com, gmlikog@gmail.com
elias.gyftodimos@gmail.com

Most of the methodologies for the solution of state-space models are based on the Kalman Filter algorithm (Kalman, 1960), developed for the solution of linear, dynamic state-space models. The most straightforward extension to nonlinear systems is the Extended Kalman Filter (EKF). The Limiting EKF (LimEKF) is a new algorithm that obviates the need to compute the Kalman gain matrix on-line, as it can be calculated off-line from pre-computed gain matrices. In this research, several different strategies for the construction of the gain matrices are presented: e.g. average of previously computed matrices per interval per demand level and average of previously computed matrices per interval independent of demand level. Two case studies are presented to investigate the performance of the LimEKF under the different assumptions. In the first case study, a detailed experimental design was developed and a large number of simulation runs was performed in a synthetic network. The results suggest that indeed the LimEKF algorithm is robust and – while not requiring the explicit computation of the Kalman gain matrix, and thus having vastly superior computational properties – its accuracy is close to that of the “exact” EKF. In the second case study, a smaller number of scenarios is evaluated using a real-world, large-scale network in Stockholm, Sweden, with similarly encouraging results. Taking the average of various pre-computed Kalman Gain matrices possibly reduces the noise that creeps into the computation of the individual Kalman gain matrices, and this may be one of the key reasons for the good performance of the LimEKF (i.e. increased robustness).

Keywords: Origin-destination flows’ estimation and prediction, state-space models, Extended Kalman Filter (EKF), Limiting Extended Kalman Filter (LimEKF)

TELEMATICS BUSINESS AND MANAGEMENT IN BAHRAIN MARKET

Marwan Rajeh Hussain1, Abduljalil Zainal2, Wael Mohamed Elmedany3, Mohamed Waleed Fakhr4

1Telematics Department (consultant), Spatial Technology Solutions (STS),University of Bahrain
P.O Box 32038, Manama, Kingdom of Bahrain
E-mail: marwan.rajeh@sts-int.net
2CEO, Spatial Technology Solutions (STS), University of Bahrain
Manama, Kingdom of Bahrain
E-mail: abduljalil.zainal@sts-int.net
3Computer Engineering Department, University of Bahrain
P.O. Box 32038, Manama, Kingdom of Bahrain
E-mail: welmedany@uob.edu.bh
4Electronic Engineering Department, University of Bahrain
Manama, Kingdom of Bahrain
E-mail: waleedfakhr@yahoo.com

The aim of this paper is to present and discuss issues related to the telematics business and management in Bahrain. Telematics is a part of Information and Communication Technologies (ICT), which plays a major role in the economic development of countries. Telematics applications are becoming increasingly important in modern transportation to increase reliability, safety and security of both vehicles and drivers. There are many applications for telematics; some of these applications are telematics for educations, telematics for health, and vehicle telematics. One of the most important applications of telematics is vehicle telematics, which includes vehicle tracking, fleet management, container tracking, trail tracking. In this paper we are focusing on vehicle telematics business and management in Bahrain market.

Keywords: Telematics, ICT, Vehicle Telematics, GPS, GSM, GPRS, navigation, fleet management

PLANNING AND FINANCING SCHEMES LINKED TO THE DECISION-MAKING FOR THE INTERCONNECTION OF LONG-SHORT DISTANCE TRANSPORT

Eftihia Nathanail1, Giannis Adamos2

1University of Thessaly, Department of Civil Engineering
Pedion Areos, 38334 Volos, Greece
Ph.: +30 24210 74164. Fax: +30 24210 74131. E-mail: enath@uth.gr
2University of Thessaly, Department of Civil Engineering
Pedion Areos, 38334 Volos, Greece
Ph.: +30 24210 74158. Fax: +30 24210 74131. E-mail: giadamos@civ.uth.gr

The development of interfaces between long and short distance transport networks is associated with the general processes planned by central governmental bodies; and the degree of their efficiency depends heavily on the successful cooperation among the involved planning stakeholders at various territorial levels. At the same time, no matter how efficient the planning process may be the lack of the appropriate financial planning and the coordination of the involved stakeholders for finding the required resources, affects the development of successful long and short-distance interfaces. Towards this direction, the aim of the present paper is to investigate the planning and financing schemes developed in longshort interconnection in representative European countries, and assess how these processes are linked to the decision-making processes at a local, regional, national and European level. In addition, obstacles and barriers in the relative processes are indicated and methods for their alleviation are proposed.

Keywords: modal interconnection, terminal interfaces, decision-making, planning, financing, questionnaire survey

DISTINGUISHING BETWEEN SPATIAL HETEROGENEITY AND INEFFICIENCY: SPATIAL STOCHASTIC FRONTIER ANALYSIS OF EUROPEAN AIRPORTS

Dmitry Pavlyuk

Transport and Telecommunication Institute
Lomonosova 1, Riga, LV-1019, Latvia
Ph.: (+371)29958338. E-mail: Dmitry.Pavlyuk@tsi.lv

A problem of distinguishing between frontier heterogeneity and inefficiency is widely acknowledged in benchmarking. A special type of heterogeneity, based on the spatial structure, can significantly affect performance estimates in the airport industry. In this research we presented a general specification of the spatial stochastic frontier model, which includes spatial lags, spatial autoregressive disturbances and spatial autoregressive inefficiencies. Maximum likelihood estimator has been derived for this model. Applying the suggested model specification to the European airports dataset, we discovered presence of significant spatial heterogeneity, which leads to biased estimates of efficiency, received using classical models.

Keywords: airport efficiency, spatial stochastic frontier, maximum likelihood estimator

MOBILE AUTONOMOUS ROBOTS – A NEW TYPE OF CITY PUBLIC TRANSPORT

Vasili Shut1, Valery Kasyanik2

1Brest State Technical University, Brest, Belarus,st. Moskovskaja, 267
Ph.: +375295264295. E-mail: lucking@mail.ru
2Brest State Technical University, Brest, Belarus, st. Moskovskaja 267
Ph.: +375295274539. E-mail: vvkasyanik@bstu.by

In the article the problem of modern cities – transport jams – is taken up. We propose several variants of solution and one of the main – the use of autonomous mobile robots as public transport. This is caused by active development of robotics. The article contains the review of the latest achievements of this perspective sphere and technical characteristic of two mobile robots for providing effectiveness of traffic. Functioning of robots takes place in confined environment with distinct infrastructure.

Keywords: robot, intellectual transport system, jam, city public transport, passenger traffic

INDIVIDUAL ATTITUDES AND SHOPPING MODE CHARACTERISTICS AFFECTING THE USE OF E-SHOPPING AND RELATED TRAVEL

1Federica Crocco, 2Laura Eboli, 3Gabriella Mazzulla

University of Calabria – Faculty of Engineering, Department of Land Use Planning P. Bucci, cubo 46/B, 87036 Rende (CS), Italy
1Ph. +39.984.496754. Fax +39.984.496784. E-mail: federica.crocco@unical.it
2Ph. +39.984.496784. Fax +39.984.496784. E-mail: laura.eboli@unical.it
3Ph. +39.984.496782. Fax +39.984.496784. E-mail: g.mazzulla@unical.it

New telecommunication technologies and services have caused important challenges on travel behaviour and trip characteristics. Existing literature studies show many different outcomes regarding the effects of the new technologies on the participation of people to their personal activities and related travel; specifically, e-shopping may produce the reduction of shopping trips (substitution effect), but also an increase of trips thanks to the reuse of the travel time saved for other activities and trips (complementarity’s effect). The focus of this study is to analyse the aspects mostly affecting consumer choices of purchasing goods by web or in-store, with the aim of understanding how to operate so that e-shopping can positively modify consumers’ travel behaviour. Our research findings show that individual social and economic factors, consumer attitudes, and shopping mode characteristics influence the usage of online shopping. An experimental survey addressed to a sample of Italian consumers is used in the study.

Keywords: e-commerce; travel behaviour; logistic regression models

SOME APPROACHES TO THE ROLLING WHEELS’ DYNAMICS MODELLING IN THE WEIGHT-IN-MOTION PROBLEM

Alexander Grakovski, Yuri Krasnitski, Igor Kabashkin, Yuri Sikerzhitski Victor Truhachov

Transport and Telecommunication Institute
Lomonosova 1, Riga, LV 1019, Latvia
Ph.: (+371) 67100654. Fax: (+371) 67100535. E-mail: avg@tsi.lv

Some possibilities of fibre-optic sensors (FOS) application for measuring the weight of moving vehicles realized in weightin- motion (WIM) systems are discussed. As the first, the model of small-buried seismic sensor transient response excited by a car tyre interaction with asphalt-concrete road pavement is proposed. It is supposed that a seismic wave received by the sensor is the vertical component of surface Raleigh wave. The model is based on supposition that a tyre footprint is acceptable to consider as some array of point sources of these waves. The proper algorithms permit to vary different parameters of the array excitation, as to footprint dimensions, load distribution, car velocities and others. The set of Matlab codes is worked out for seismic pulses modelling and processing. The second way considered is to simulate the FOS signal in the basis of differential equations describing a deformable wheel behaviour, or wheel oscillations, in order to identify relations with optoelectronic mechanical parameters. An attempt to find the mass of the vehicle is based on minimizing the discrepancy between the actual FOS signal and the solution of the differential equation. The accuracy of the evaluated weight depends on many external factors, the mathematical modelling of them are expressed in the numerical values of the coefficients and external stimuli. The influence of these factors are analysed and tested by simulations and field experiments. One of ideas in dynamic weighing problem solution should consist in evaluation of position of virtual gravity centre of the vehicle in time. The processing algorithm of the data received from the FOS is proposed based on conception of database retaining in some reference system memory. Certain requirements concerning the elements and blocks of the algorithm are defined as well. The reference system is realized as the digital filter with the finite impulse response. The method to estimate the filter coefficients is worked out. Several experiments with this algorithm have been carried out for the vehicle identification with the reference loads adopted from real data. The different factors have an influence on the measurement accuracy of FOS. The roadbed features, temperature, nonlinearities and delay effects in FOS are among them. The results of laboratory and field measurements with FOS responses to different axle’s loadings are presented. Charging and inertial characteristics of FOS under the impact of various external factors (protective cover, temperature, contact area, and installation mode especially) as well as their approximations are investigated. It is found that the final calibration of the FOS has to be done individually and only after it has been installed in the pavement. Certain methods and algorithms of linearization, as well temperature and dynamic errors compensation of FOS data are discussed.

Keywords: Weight-in-motion, WIM systems, fibre optic sensors, sensor’s sensitivity, tyre footprint, road pavement reaction, sensor response modelling

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