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Slavko Šarić, Jozo Balić, Rudo Vidović
2004 (Vol 16), Issue 6
This article presents a review of the existing networks andthe NGN concept. By analysing the condition of the existingtelecommunication networks and services it is obvious that theyare different single-se1vice networks that cannot meet the requirementsof the users for various se1vices. The increased demandsof the users for telecommunication se1vices have inducedthe introduction of liberalization in the telecommunicationmarket. That opened the door for competition and greatinvestments in the development of telecommunication networks.The existing telecommunication networks orientated to thetransmission of voice and the existing data network could notbe adapted to new requirements without difficulties. That is thereason why the search for a solution for convergence and unionof a great number of different single-service networks started.The basic requirement was reduced in the end to the conceptionof the universal wideband data network that can meet all thedemands of the users by dividing the resources. As a collSequenceof that it was necessmy to find the solution for the transmissionof voice by a data network. The solution was seen in theerection of softswitch architecture for VoiP. Thus, the voicewould be transmitted by packets as one of the components indata transmission. It was necessary to define protocols for enablingthe operation in the NGN conception, as well as to thoroughlyobserve the problems of the JP telephony operation in regardto the real-time voice component. Apart from these tasks itwas necessmy to see how to adapt the existing networks into theNGN conception and to provide interaction between differentnetworks and different layers of networks by applying certainstandards and protocols. The awareness of the necessity ofgradual introduction and realization of NGN conception hasbecome obvious, always in the relation to the existing conditionof PSTN and the users' demands. Special attention should begiven to the introduction of IN as a tool for the realization ofadditional se1vices and for enabling the control in NGN. Theproblem of JP routers for NGN has also been mentioned, aswell as the importance of the new core generation of optical networks.The conceptual framework of NGN is based today onIP/ATM transport technology, which is at this level of developmentgenerally accepted as the optimal transp011 solution. The problem of addressing caused by the insufficient address spaceof Ipv4 has been stressed and the solution of that problem hasbeen anticipated with the introduction of lpv6 technology,which, due to its complexity and high costs, would be graduallyintroduced by a dual approach into the system.The differentiating elements of NGN in relation to the existingnetworks have been specially pointed out. The modulm;that is, plane nature of the NGN conception in relation to thevertical and hierarchical conception of PSTN has beenstressed, as well as the pdvileges that this open conception offerswhen choosing the equipment of the highest quality by differentmanufacturers. Both existing, voice (TDM) and data(NGN) (ATM/IP), networks will act parallel in the next yearsuntil new solutions to NGN will have been introduced.
Iztok Ostan
2004 (Vol 16), Issue 6
The empirical sociological studies of exploitation are nowadaysrare in Slovenia and in other countries as well. Researchamong Slovene students showed that according to their statementsthere is much exploitation in Slovenia and that it hasbeen increasing. It showed also that statements of students donot differ much from the results of public opinion research regardingexploitation, nor from the statements of irregular studentswith long working experience. It was also found that thereare no substantial differences in statements of Italian and Slovenestudents. Traffic technology students are a group amongfull-time students who agree most with the statements that thereis much exploitation and that it has been increasing. A hypothesiswas set that statements of these students could be used as anindicator of general student opinion regarding exploitation.
Mirsad Kulović
2004 (Vol 16), Issue 6
The road freight transport costs are a function of numerousfactors that could be grouped according to their characteristicsand level of utilization of company's technical and human potential.The different input prices, product characte1istics, truckconfiguration, geographical characteristics, road conditions,and driving characteristics make it very difficult to estimate thecurrent transportation costs for a particular company. To investigatethe main factors that may affect road freight transportcosts, it is useful to analyze the influence of truck fleet operationalparameters on these costs. This paper desc1ibes freighttransport costs model based on tntck fleet operational parameters.The explanation of the model is given through a practicalexample. The model enables changes of input parameters andreflects the influence of different management decisions whichhave an impact on transportation costs.
Andrej Godec, Boštjan Hernavs
2004 (Vol 16), Issue 6
Over the past few years we have been witnessing a rapid andundreamt of development in the communications field. Every·one wants to communicate with others all the time. Industry isa major generator of these changes. But users do not like fastand frequent changes because they usually mean nothing good.The majority is satisfied with basic necessities and there is ahuge problem in t1ying to convince them into something new.There is a difference between technical and marketing sector.We are dealing with economy, promises, contracts. But industrywants more: new users, fresh money for new investments.The aim of this article is to find a technical solution for increasingthe existent optical cable capacities. The purpose is notto replace the existing cables but to use advanced technologyand to improve economy, safety and reliability of all kinds ofcommunications which use optical transmission medium.
Slavko Šarić, Anto Bilobrk, Davor Nađ
2004 (Vol 16), Issue 6
Voice transmission over JP networks (Voice over InternetProtocol) represents one of the ways in which voice and datanetworks are integrated. The future development is based onthe explosion of the Internet as the means of communication,with the openness of standards and the readiness of the equipmentmanufacturers to accept such standard and to unify it.The service providers find interest in introducing new servicesthat are not based only on voice transmission, but voice becomesonly one of the applications that are realised over the JPnetworks. Voice transmission over the JP technology is at themoment not at the level of the existing quality of services, butthe coming solutions in the near future will enable Vo!P as thestandard operative solution. The advantages are reflected in theincrease of income keeping the current users and attracting newones, investments into infrastructure will maximize the opportunitiesfor packet service development, strengthen customers'loyalty and reduce operative expenditures, the services will bewidespread - long-distance international services or nationalservices of calling cards can be located at almost any European,African, or Central-Eastern count1y and directed to almost100 percent of the population. With the advantages of lowinitial costs of the new POPs (Points of Presence), the serviceproviders can suddenly expand their presence to many countriesor destinations.
Goran Zovak, Goran Beraković, Ivica Ostrun
2004 (Vol 16), Issue 6
Traffic accidents in road traffic are becoming an increasingproblem regardless of whether there is only material damage orserious injuries and fatalities. There are various causes resultingin traffic accidents, and this paper describes the reconstructionwork on a section of the motorway in order to improve thetraffic safety. Also, the results of the given reconstruction havebeen analysed.
Velimir Kolar, Vinko Jenić, Boris Magličić
2004 (Vol 16), Issue 6
The paper deals with all the resources and factors that determineor influence to any extent the technological process ofstaff of train rostering. The Timetable, Train Traction andTraction Vehicle Maintenance Sector and the legal regulationsstipulate the basic parameters for rostering and these are explained.The paper also analyses the contents and the methodof producing the rostering plan which shows all the practicaldrawbacks and the limiting factors that influence significantlythe possibility of corrections in order to improve the utilisationlevel of the staff of train. A model has been developed with thepresentation of the factors that influence the staff of train rostering.The paper also shows the project of a software solutionfor the staff of train rostering with the defined and explainedClipper program.
Bojan Pirš
2004 (Vol 16), Issue 5
The joining of the Republic of Slovenia in the EuropeanUnion gives special significance to the economic subjects becausethe past market and competition are open directly for theSlovenian economic subjects. It means that competition will increasefor the market of transport service. There will be morepossibilities for the enterprises to move faster towards culmination,the phase of degeneration - crisis. Since the business crisisendangers the future existence and development of the Slovenskeieleznice Holding, it has become very important to be ableto control it. In order to avoid this, the Slovenske ielezniceHolding needs clear and methodical business politics whichmeans common interconnections and interacting influence ofelements (rules, criteria, measures and activities), which constantlymove, change and develop. The business politics givesaims and feedback as a condition for the existence and functioningof everything, so it cannot be regarded only as a globalprogramme of development, but rather as a very complex anddynamic system.The elements of the business politics model- incorporatingfactor to the European traffic flows are the sub-politics of thebusiness politics which influence its realisation; production,staff, marketing, finances and development sub-politics. Theevaluation of the elements of the model has taken into considerationtheir condition and meaning in the realisation of the businesspolitics in 2003 and their expected values in 2008, whensimple transmission of achievements is expected in the railwaytraffic in the European Union and in the year 2012 when a repeatedenlargement of the European Union is foreseen.The model of business politics -factor of integration of theSlovenske ieleznice Holding into the European traffic flows isan experiment to restore the collaborating relation between certainelements of the model.
Teodor Perić, Nada Štrumberger, Dean Perić
2004 (Vol 16), Issue 5
As an interdisciplinary science, ergonomics needs to makethe operating of traffic safer, faster and more reliable, for thesake of higher profitability and generally improved economiceffects. This is achieved by adapting and shaping the workplace,machines, transport means, equipment, physical environment,working process etc. according to experience abouthuman anatomic physica~ sociologica~ intellectual and otherminimal, average or maximal capabilities. Therefore, it is necessaryto analyse ergonomics from the standpoint of better productivenessof humans, greater safety (comfort) and security ingeneral.
Slavko Šarić, Zoran Božanić, Romeo Svalina
2004 (Vol 16), Issue 5
During the last decade of the 20th century, intensive developmentof telecommunication infrastructure set high requirementsregarding technical documentation that started to haveproblems in following the changes in the network. In the lastseveral years HT made a great shift regarding automation andpresentation of technical documentation, that is introductionof GIS (Geographic Information System), as precondition forthe introduction of DIS (Documentation Information System),thus realising the necessary preconditions to use the gatheredand organised spatial and atllibute data, for higher quality ofanalysis, processing and repair of interference in the telecommunicationnetwork The aim of this paper is to inform aboutthe segments and computer programs used for the developmentof technical documentation.
Stanislav Pavlin, Slavko Roguljić, Vedran Ivančić
2004 (Vol 16), Issue 5
Capital city airports in the European countries realise trafficvolume of several thousands to several hundred thousandaircraft operations i. e. landings and takeoffs annually. In itsAirport Planning Manual, the International Civil Aviation Organizationrecommends that the capital city airports have atleast two runways in order to avoid complete closing down ofthe airport in cases of aircraft accidents on the runway or therunway strip, due to repair or maintenance of the runway, removalof snow, unlawful interference in civil aviation etc. Thepaper analyses the current situation in traffic and the capacitiesof the manoeuvring areas at the European capital city airports.
Gordana Brčić, Vinko Vidučić
2004 (Vol 16), Issue 5
This paper analyses the features of passenger liner shippingcompared to tramp shipping as well as human resources ofliner companies. The biggest Croatian passenger liner company,Jadrolinija d. d., Rijeka is analysed as well as the capacityof the Croatian passenger liner companies in terms of the needsof tourism and promotion of the Croatian shipbuilding. Trendsthat appear in the capacity and characteristics of ships used inliner shipping and for cruising indicate the necessity of complexapproach to stimulating the development of these branches. Acomplex approach to shipping, tourism and shipbuilding is expectedto significantly contribute to restructuring of the Croatianeconomy and to stimulating the export sector.
Robert Muha
2004 (Vol 16), Issue 5
Car washing is a task performed by every passenger carowner more or less frequently, mainly to achieve a finer appearanceof the vehicle rather than for the need for cleanness.In the transport business, the owner's concern is to presentclean and orderly vehicles on the road as a relevant external elementof order, implying good corporate image to customers. Onthe other hand, in dangerous goods transportation there areother reasons requiring special technology of washing, applicableto the transport means used, depending on the change oftype of goods in carriage, the preliminary preparation of a vehicleto load the cargo, or to undergo maintenance.Water applied in the technology of washing collects the residueof goods carried in the vehicle and is polluted to such an extentthat it cannot be discharged into sewers - nor directly into awatercourse - without previous treatment.The paper presents a solution model and a sequence oftechnological procedures involved in an efficient treatment ofthe polluted wastewater in tank wash stations, in which mostlyvehicles carrying ADR goods are washed.
Peter Vidmar, Stojan Petelin
2004 (Vol 16), Issue 5
The basic aim of this treatise is to research the relevant featuresof the control and management of fire event in road tunnels.The simulation of 200 meters long cut out of the road tunnelis performed with the computer code FDS (Fire DynamicsSimulator) which is based on the computational fluid dynamics.FDS is used to simulate fire dynamics behavior in three differentscenarios: natural ventilation, forced ventilation with axialventilators and vertical smoke extraction.It is believed that the present research, the methodology appliedand its findings should promote and improve safety andreliability of fire safety in road tunnels and to cope with thecomplex contemporary logistic demands of safety and reliabilityin the transportation of passengers and goods.
Rudi Čop, Franc Dimc
2004 (Vol 16), Issue 4
From the very beginning of its usage the navigation systemGPS has been applied in studying the cases of the car followingbehaviour of two-vehicle platoons. The navigation receiver isused for vehicle position and speed data collections. The measurementaccuracy is to be improved by the real-time dGPScorrection-data or by additional data post-processing. For additionalmeasurement of the vehicle-to-vehicle separation, bothvehicles should be equipped with a GPS receiver. The vehicle-to-vehicle separation is calculated later on, during the datapost-processing.This paper describes the choice of the experimental setup,on the basis of the radio-navigation system GPS, which may beused for recording the data on location, speed and time. Thepresented measurement results have been attained in two steps:first, the data were collected, through the process of tracking oftwo-vehicle platoons in real life traffic-flow, and then processed.The selected mathematical model is based on the PIDcontroller in the closed-loop control system. It enables evaluationof the measurement results and assessment of the behaviouralelements of each driver.
Elen Twrdy, Ivan Smredu
2004 (Vol 16), Issue 4
Maritime traffic, in particular container transport, is experiencingrapid and technologically advanced development oftransport means. This development has led to the constructionof vessels of constantly increasing capacity that transport containersaround the world. Vessels with a capacity of up to18,000 TEU are to be expected and port development will haveto adapt to these trends.This trend will inevitably change conditions in the northernAdriatic, which is lacking the maritime and market conditionsto accommodate large dimension vessels. Hence, the questionis raised whether the northern Adriatic ports will be able to establishconnections that will allow them to maintain their marketshare in relation to western European ports. The solutioncan be provided by an optimal feeder vessel service.
Ivan Mavrin, Damir Knežević, Ivo Jurić
2004 (Vol 16), Issue 4
Fine particles that can be found in the exhaust gases of dieselengines and have a diameter of 2. 5 !Jl1l and ultra-fine particlesof 0.1 !Jl1l in diameter are mainly products of the combustionprocess. Experiments on animals have proven that theparticulates from the ambient air can cause damage to thelungs and can even end fatally. Therefore, it is necessary to reducethe mass of fine particles in the atmosphere and the numberof ultra-fine particles. Numerous studies of experiments onanimals have proven the toxicity of these particles. The air saturatedby particles resulted in cardio-pulmonary diseases in animalmodels. The epidemiological studies have shown the interdependenceof the increase in mortality and morbidity, especiallyin the elderly and persons suffering from respiratory ailmentsand cardio-vascular diseases. A hypothesis has been setthat the ultra-fine particles cause inflammatory reactions in alveoliand interstitium resulting in the increase of blood coagulationand deterioration of the condition in persons sufferingfrom the problems in cardio-vascular system.
Zlatko Sviben, Zdravko Toš, Miroslav Borković
2004 (Vol 16), Issue 4
Road noise disturbance on rough roads by means of loudnesssensor caused by wideband signal components with a significantimpact of tonal effects on smooth roads and in specificactions in driving lead to the annoyance of drivers. A systemicapproach has been applied for the sound quality estimation ofphysical properties of various noise sources and structuralvibroacoustic car properties and its components as an integratedparameter in car design for the purpose of the developmentand vehicle noise reduction. Simulation of the most importantcharacteristics of listening impressions was performedby modem systems of signal analysis together with the presentationof loudness, sharpness, and roughness as essential quantities.Optimization of the noise control measuring regarding vehiclesound was obtained by means of a simulation system withthe capability of the real time original sound filtering. Structuralanalysis was performed as an acoustic modal analysis on therear part and the car interior with the quantitative analysis ofsport and luxury car sounds. The possibility of active noise controlwas studied and examples are given for an application ofpsychoacoustic tools for car sound quality design. Sound qualitywas obtained by an observation of certain aspects, which areempirically or theoretically connected with the design. An experimentalsound synthesis with psychometrical measuring wasapplied. The sound quality of car interior is presented takinginto consideration the criteria of objectivity, reliability and validity.
Caj Holm, Mario Anžek, Slobodan Kaštela
2004 (Vol 16), Issue 4
This paper discusses the suitability of mobile phone positioningdata for travel time information. The Finnish NationalRoad Administration Finnra has carried out a study on thesubject (1) and managed pilot installations on two road sections(6) in order to determine the feasibility of mobile phonetracking for traffic monitoring and management purposes. Accordingto the study and the pilots, the mobile phone positioningcan provide useful link monitoring data, i. e. the travel timeand speed. Mobile phone tracking was found to be a very promisingtool for implementing travel time information service todrivers.
Teodor Perić, Andreja Lorković, Dalibor Vučić
2004 (Vol 16), Issue 4
Management planning in traffic and other activities includesa choice of missions and goals, as well as actions undertakenfor their realisation. It requires decision-making, that is,a choice among alternative trends of future actions. Therefore,planning and control are closely related.There are several types of plans: purposes or missions,goals, strategies, policies, procedures, rules, programs and calculations.Once managers become aware of the opportunities, they rationallyplan the setting of the goals and assumptions about thecurrent and future environment, finding and evaluating alternativetrends, and selecting the one that is to be followed.Therefore, planning means looking ahead and controlmeans looking backwards. The concept of overall planning,thus including traffic planning, illustrates the approach to managementwhich is based on the achieved goals.
Jasna Golubić, Velimir Kolar, Tomislav Župić
2004 (Vol 16), Issue 4
The work considers the differences in the aircraft engine exhaustemissions, as well as the impact of the emissions on theenvironment depending on several factors. These include theage of the engine, i. e. technical refinement, engine operating regimesat different thrusts during time periods: takeoff, climb,approach, etc. Also, the exhaust emissions do not have thesame influence on different atmospheric layers. The pollutantsemitted at higher altitudes during cruising have become agreater problem, although the volume of pollutants is smaller,due to the chemical complexity and sensitivity of these layers ascompared to the lower layers of atmosphere. One of the reasonswhy these problems have long remained outside the focus of interestof the environmentalists is that the air transport of goodsand people is performed at high altitudes, so that the pollutionof atmosphere does not present a direct threat to anyone, sincethe environment is being polluted at a global level and thereforeis more difficult to notice at the local level.
Jasna Jurum Kipke, Valentina Pirić, Marina Manucci
2004 (Vol 16), Issue 4
This paper deals with the application of BMW Group energystrategy communication in order to build excellent BMWcorporate image worldwide with the purpose of analyzing thecurrent situation regarding this topic on the Croatian car marketas well as analyzing the possible influence of BMW environmentprotection care and energy strategy on BMW corporateimage in the Republic of Croatia.To ensure sufficient supply of energy in order to meet the futureneeds, the BMW's chosen priorities worldwide are to promoteefficient use of today's available energy sources and to developinnovative solutions for the future. The company usesthese elements in building the desirable BMW corporate image.On the basis of the conducted surve, it was more than obviousthat these activities still do not play a large role in building agood BMW corporate image among BMW customers in Croatia.Obviously, there is great possibility for the BMW Group toimprove its corporate image in Croatia and on the similar marketsboth with the application of intensive environmental careand the energy strategy communication.
Željko Trošelj, Goran Zovak, Ivica Premužić
2004 (Vol 16), Issue 3
The analysis of the data from the case history of patientswith tibia and ankle fractures was carried out to show the significanceof identifying such conditions and the consequent implementationof transporl immobilisation as the first step intreating the injured persons. The implementation of transporlimmobilisation in indicative conditions should be imperativein providing first aid regardless of who is providing it (a laymanor a medically educated person). The tibia and ankle fracturesare easily identifiable and it is not difficult to diagnose them.The data that have been gathered lead to considering thelevel of education or negligence of the participants included inthe first aid chain. Taking into consideration the facts that thenumber of traffic accidents is increasing in the world, thatCroatia is at the very top of the list regarding the number of fatalitiesper capita, that the timely and properly provided first aidreduces the frequency of complications of the injury itself, thuscausing the reduction of the treatment costs, in our opinion immobilisationas one of the aspects of providing first aid did notlose its actual significance, but acquired additional significancewithin the framework of increased and higher-quality possibilitiesof providing first aid.
Igor Trupac, Jurij Kolenc
2004 (Vol 16), Issue 3
Today, the countries of Central andEastemEurope (CEE)have developed into a fast growing and promising part of Europe.The vision of the management of the Port of Koper is tobecome the most important logistic centre for these countries.In the future the North Adriatic region will have to cope withfurther challenge, i. e. an increasing presence of the Asian Pacificeconomies on the European continent and in the CEEcountries in particular. For the traffic flows from this source,the North Adriatic is, from the geo-transport aspects the mostconvenient seaway/ route.It was for this reason that the Port of Koper as the key companyjoined a pilot project- STLC (Slovenian transport logisticcluster) as a stakeholder. The main purpose of the STLC is topromote the Slovenian transport route using the Port of Koperas the focal point.This paper aims to: (I) review the current state of the developmentof Slovenian transport logistic cluster, (JJ) assess thepotential benefits of such a cluster for the Port of Koper (Ill) introduceinitial presentations, experiences and results.
Ratimir Dovečar
2004 (Vol 16), Issue 3
The basic aim of this treatise is to research relevant featuresof multimodal transportation chains, their advantages and disadvantagesas well as the problems of the synchronization ofwork of all the participants in multimodal transport. With thedevelopment of information technology the method of optimisationof multimodal transportation chains is more and morebased on the computer programs being representative tools insolving of comprehensive tasks.It is believed that the present research, the methodology appliedand its findings should promote and improve multimodaltransportation chains in order to cope with the complex contemporarylogistic demands of global economy.
Rudi Čop, Milan Batista
2004 (Vol 16), Issue 3
The traffic flow theory is dealing with the better understandingof the traffic flow and its improvement. Most often, the researchedsubject was been the road traffic. It is namely thatheavy traffic and traffic jams are the frequent phenomena onthe roads.The traffic flow theory incorporates the different areas ofknowledge necessary to establish a successful traffic-flow simulationmodel. Good correlation between the simulation modelresults and data collected in the open road conditions are notthe only conditions which are necessary to approve the simulationmodel as accurate. The obtained simulation results may beused for the improvement of traffic conditions, only if themodel obeys the classical laws of physics.This paper is dealing with the simple microscopic model fortwo-vehicle-platoon behaviour in the traffic flow. The model isbased on solving of the delay differential equations. The simulationmodel results have been compared with the measurementresults. The comparison has enabled assessment of the selectedsimulation model to check whether it would be goodchoice for further traffic-flow researches at the microscopiclevel.
Vladimir Marić, Zvonko Kavran, Dražen Kovačević
2004 (Vol 16), Issue 3
Public urban transit system is of special significance in thetraffic and economic system of big cities. Continuous laggingbehind of the public transit system development compared tothe city development can be noticed as a consequence of thetraffic policy and the fascination by the passenger cars. Plannedorientation of the urban traffic systems is of a recent date. Thispaper tends to give incentive to the need for a more complex urbanplanning and planning of traffic in a unique multidisciplinaryprocess within the urban planning system.
Drago Pupavac, Ratko Zelenika, Marinko Jurčević
2004 (Vol 16), Issue 3
The main goal of this scientific study is to explore the significanceof human potentials management in micro and macrotransport systems, i. e. whether and to what extent do the humanpotentials represent the factor of growth and developmentof transport systems. The facts gathered by this study shouldrepresent quantitative starting points for viewing the specifics oftransport service productions and future movements on thetransport labour market, and the possibilities of informationtechnologies implementation in transport human potentialsmanagement optimisations, all with the aim of producing newand of improving the inherited comparative advantages of theCroatian transport systems.
Antun Stipetić, Srečko Kreč, Vinko Jenić
2004 (Vol 16), Issue 3
Considering the strategy of the railway traffic infrastructuredevelopment of the Republic of Croatia, the authors have alsoconsidered the restructuring of the railways in EU and Croatiawith the aim of insuring the very complex process being carriedout in everyday lives, full ofinterdependencies. First, the paralleldevelopment of the three networks that form the EU railwayssystem is given, together with their characteristics and futureroles. These are: the network of the Trans-European conventionalrailway line system, the high-speed railway line network(HS Net) and the network of railway lines intended prevailinglyfor the cargo transport (RTEFF, TEFFN). This is followed by apresentation of the basic aims of the strategic development ofrailways in Croatia and the overview of the conditions and thenecessary activities on the Corridor railway lines so as to preparethem for the integration into theE U traffic system. In elaboratingthe development strategy of the railway traffic infrastructurein Croatia, a summarised overview of the objectivesand the necessary activities is given, in order to renew the railwaynetwork, and to reconstruct it so that it could meet the requirementsset by the AGC andAGTC standards which are thecondition for the Pan-European railway lines.
Mirko Čičak, Tomislav Josip Mlinarić, Borna Abramović
2004 (Vol 16), Issue 2
This work presents the methodological procedure of determiningthe throughput capacity of the railway lines under theconditions of organising traffic with parallel and non-parallelgraphs, i. e. travelling of trains at the same and different speeds.If the non-parallel graph traffic organisation is applied, i. e.trains of different speeds travel along the line, which is often thecase, then the railway line capacity can be calculated by meansof the so-called 'coefficient of elimination'. Therefore, thework defines the coefficient of elimination and presents themethodological approach to its determination for various trafficconditions, i. e. for single-track and double-track lines. Also,some empirical formulas are given which determine the coefficientof elimination.
Ivan Bošnjak, Ibrahim Jusufranić, Vinko Višnjić
2004 (Vol 16), Issue 2
Deployment of flexible traffic control, pre-trip, on-trip,guidance and other ITS services require considerable researchtoward the development of appropriate methodological frameworkand tools. In this paper, adapted modelling framework fordynamic mu/tic/ass traffic assignment (DMTA) in ITS environmentis proposed and elaborated. DMTA system uses trafficdata associated with three backdrops: time, space and defined'user classes'. The proposed structure of DMTA system includesmodules for 0-D estimation and prediction, real-timenetwork state simulation, consistency checking, updating functions,resetting functions. The methodological tools for solvingDMTA problems include combination of mathematical programming,simulation and heuristic methods.
Tone Magister
2004 (Vol 16), Issue 2
The paramount priorities for safe implementation of a singlepilot manned cockpit concept and the futuristic concept of asingle pilot acting as a supervisor for a fully automated aircraftflying on incessantly self-optimised trajectories are eliminationsof the risk of mid-air collisions and of conflicts resulting fromthe lack of safe airborne separations. Avoidance procedureswith initiation of descent behind the intruder for conflict resolutionbetween a pair of aircraft where one of them is in the vicinityof the top of its descent represents merely one little piece ofthis giant puzzle.
Ivo Marković, Dalibor Vučić, Mirela Muić
2004 (Vol 16), Issue 2
The current condition of the Zagreb - Rijeka railway line,and the throughput capacity of the line on the Botovo - Rijekasection reflect the overall situation of the railway traffic on thesection of the Corridor Jib. The existing condition needs to bereconstmcted by investing in the infra- and supra-structure.Along with the modernisation the increasingly present environmentalawareness should bring to the gradual shift of cargofrom road to railways. Such principle would contribute to theincrease in passenger traffic and eventually of the maritimetraffic as well.
Borivoj Galović, Doris Novak, Tomislav Kaštelan
2004 (Vol 16), Issue 2
The helicopter generated noise at and around the airports islower than the noise generated by aeroplanes, since their numberof operations, i. e. the number of takeoffs and landings ismuch lower than the takeoffs and landings of the aeroplanes.Out of some hundred operations a day, helicopters participatewith approximately 15%, but the very impact of noise is by nomeans negligible, since the number of helicopter flights aboveurban areas is constantly increasing.This paper attempts to analyse this phenomenon and thetype of helicopter generated noise, its negative impacts, to explainthe flight procedures and the operative procedures duringtakeoff, landing and overflight of helicopters in operations inthe vicinity and outside airports, as well as the methods of measuringand determining the limit of noise [eve~ and the resultingproblems.
Zoran Radišić
2004 (Vol 16), Issue 2
These days we are witnessing an increase of container trafficin general and at sea in particular. In order to economizetheir business the ship owners are building bigger container vesselswhich can carry up to 8000 TEUs (Maersk line) and otherbig carriers are following suit. On the drawing board is the vesselof 12000 TEUs from the mentioned ship owner. Obviously,such large quantity of containers requires highly efficient lashingequipment in order to secure them, particularly thosestowed on the deck Under the deck, almost as a rule all contemporarycontainer ships have cell guides as securing devices.Attention in this work is focused on container lashing systemexposed on the ship's deck and the relevant forces acting on thelash system during transportation at sea. Once containers areloaded on the ship's deck they should be safely secured by oneof the lashing systems in order to prevent damage and that is theprincipal task of the lashing equipment engaged within theframe of the lash system. In order to fulfill its objective theforces acting on the container should be properly calculated.The acting forces, their influence and the way of calculatingthem have been explained for all the major ship movementsand suggestions for optimum lashing equipment are given.
Dušan Fabe
2004 (Vol 16), Issue 2
Like teachers of subject related languages in general alsothe teachers of traffic related language are faced with the challengesof contemporary, technologically fast developing society.In modem information times students are much better informedthrough satellite TV; Internet and numerous publications.On the other hand, getting hold of all this information isno easy task for teachers. If they want to be interesting andmake students attend their classes, they must even be ahead oftime or at least be the first to pass on fresh information. Here aquestion arises about the current role of language textbooks intertiary education. Writing of a good textbook requires at least ayear or two, considering the time from its conception to publication.However, by that time it is no longer up-to-date. One ofthe solutions to the problem is presentation of current articlesfound by students in various contemporary scientific and technicalpublications. The present paper gives recommendations,based on long experience, how to acquire traffic-related languagewith such presentations in class.
Elen Twrdy
2004 (Vol 16), Issue 2
Over the last fifteen years the European transport markethas witnessed a growth of container traffic which today reachesapproximately 50 million TEU per year. From 1997 to 2002,container traffic in the northern European ports increased from14 to 20.6 million TEU per year, in the ports of the westernMedite'anean from 6 to 10 million TEU per year, and in thenorthern Adriatic ports from 0. 69 to 0. 74 million TEU per year.The ports of the northern Adriatic are located in three states(Slovenia, Croatia and Italy) with different statuses in relationto the common European market. In addition, different developmentlevels of these states are reflected in different levels ofinternational commercial exchange, the development of the existinginfrastructure and plans for the construction of new infrastructures.However, all three countries share a common goaltoincrease their competitiveness in comparison with the westemEuropean ports.
Eduard Missoni, Igor Bogović, Vinko Višnjić
2004 (Vol 16), Issue 1
Among numerous participants in road traffic there are alsothe cyclists. Cycling has become during the recent years one ofthe major components of the modem living, even in Croatia. Inalmost all the developed countries of the world, cycling isemphasised as an activity which improves health and contributesto the improvement of overall physical fitness and environmentalprotection. During the period between 1 January 1996and 31 December 1999, an analysis of the number of cyclist accidentsin road traffic was carried out. Special attention waspaid to the number of injured cyclists. In 1996, in road traffic,there were 1,218 cyclist accidents in which 912 (74.9%) cyclistswere injured. In 1997, there were 1,146 incidents and accidents,with 854 (74.5%) injured persons. In 1998, there were 1,167accidents, 887 (76.0%) injured. In the last study in 1999, thetotal number of cyclist accidents amounted to 1,230, and thenumber of the injured cyclists was 924 (75.1% ).Every event resulting in a more or less severe disability is agreat distress and great damage to every injured person as individualas well as for the family and eventually for the society asa whole. This paper recommends certain measures and proceduresthat should substantially reduce the traffic accidents andincidents which involve cyclists.
Jani Beko
2004 (Vol 16), Issue 1
The paper deals with the estimation of demand functionsfor services of public railway passenger transportation in thecase of Slovenia. Six demand functions were selected and separatelyinterpreted. The aggregate values of demand elasticitiesreported in this paper suggest that the railway passenger demandis price- and income-inelastic. Coefficients of incomeelasticity below one show that the services of railway passengertransportation in Slovenia can be classified among normalgoods. A hypothetical increase in average real fares leads to apercentage decrease in the number of passengers traveling byrail that is smaller than the percentage increase in fares. The estimatedprice elasticities imply that, in the short run, there is potentialfor improving revenues of the railway operator by increasingaverage real fares.
Serđo Kos, Zdenka Zenzerović
2004 (Vol 16), Issue 1
This paper presents the mathematical model for solving theproblem of defining optimal cargo transport structure, occurringwhen, on a predefined sailing route, adequate number ofcontainers of various types, masses and sizes, possibly includingRO!RO cargo, is to be selected, i.e., a 'container lot' is to beestablished in loading ports with the aim of gaining maximumship profit and, at the same time, of exploiting useful load andtransport capacity of container ship as much as possible. Theimplementation of the proposed model enables considerableincrease in the efficiency of container ship operations. Themodel was tested using a numerical example with real data.The applied post-optimal analysis examines the influence ofchange in some values of the mathematical model on the resultingoptimal program.
Andrej Grebenšek, Stanislav Pavlin
2004 (Vol 16), Issue 1
LjubljanaAirport is the main and central airport of the Republicof Slovenia that serves the needs of the major part of thecountry as well as the needs of the eminent regions across theborder. Due to its proximity to the capital of Slovenia, it is ofspecial importance for the country. The traffic at Ljubljana Airportconsists of IFR and VFR traffic. In calculations, however,only IFR traffic is considered. Although the VFR traffic participateswith a significant share in the total amount of traffic, it isso flexible that in the end, it only contributes to the overall capacityof the runway.LjubljanaAirport is specific because there is no taxiway tillthe holding position of runway 31. Aircraft generally land onrunway 31. This is the only available instrumental runway forlanding. Take-offs can be executed in the directions 31 or 13.Both directions are considered in the calculations. The basiccalculations are done on the assumption that take-offs andlandings are executed in the same direction, that is, on runway31. This presents a normal procedure at traffic peaks since sucha situation is clearer, easier and safer for an Air Traffic Controllerto handle. The present traffic load at the airport is not soheavy, therefore in quieter periods of the day aircraft land onrunway 31 and take off from runway 13. This procedure reducesthe capacity of the runway and the calculations for ithave been carried out at the end.
Igor Jakomin, Marino Medeot
2004 (Vol 16), Issue 1
The moment the Republic of Slovenia joins the EU all theservice offices or agencies related to cross-border operations, inparticular the freight fmwarders, will feel the consequences reflectingthese issues, or resulting therefrom:- In the field of legislation, no major direct consequences areexpected, but rather some indirect ones;- Bigger freight forwarders, better provided with capital andpresent globally will affect the operations arising from thechanged market position in the common European logisticalmarket;- As result of market changes, certain adverse financial effectswill occur in some forwarders. This will affect the social positionof employees as well;- The consequences in the macro-economic level will notonly reflect on the social area, but also on lower newlyadded value, and on some non-exploited part of the capital.The facts listed above show that the accession of Sloveniato the EU will bring about a series of adverse consequences inall freight forwarders in the first stage. The economic consequenceswill be mainly visible in the decrease of revenues offreight forwarders, whereas the social outcome will reflect in redundancies.These will lead to closing-down, liquidation orbankruptcy of minor freight forwarding agents.
Tomaž Tolazzi
2004 (Vol 16), Issue 1
The problem of minor vehicles crossing or merging into themajor stream at unsignalized priority-controlled intersections iswell-known. Numerous solutions involve various assumptionsconcerning the major headway distributions, number of majorlanes, critical gap distributions, etc. Such cases can be dividedinto two main groups: intersections with two streams (one majorand one minor stream) and intersections with more thantwo streams (more than one major stream and one minorstream). At roundabouts, also at single-lane roundabouts,there are similar problems like the ones at other unsignalizedpriority-controlled intersections. A vehicle at the roundaboutapproach can only cross the pedestrian crossing when a sufficienttime-gap between two pedestrians (or cyclists) is provided.A vehicle at the roundabout entries can only merge into the majorstream when a sufficient gap between the two vehicles in themajor stream is provided. Because of that, single-lane roundaboutscan also be treated as unsignalized intersections withtwo major lanes: the first one in its circulatory roadway and thesecond one on the pedestrian crossing.
Katica Miloš, Ivan Miloš, Danko Čurepić
2004 (Vol 16), Issue 1
The saving of energy by reducing the mass of the materialrepresents one of the basic requirements in the development ofthe transport technology. High potential in this direction hasbeen recognised in the relatively new group of materials knownas the composites. Their application is expected to achieve greatreduction in the mass of the transport means, especially theroad and railway vehicles. This paper attempts to present informationabout the composites, their status as well as the possibilitiesof their mass implementation.
Joso Vurdelja, Davor Žmegač, Valentino Rajković
2004 (Vol 16), Issue 1
The analysis of the current condition regarding the trafficinfrastructure of the town of Kutina it is possible to concludethat in some elements it fully satisfies the needs of its users,whereas in some other elements there are certain divergences. Itis specially emphasised that a significant part of the trafficproblems of Kutina cannot be solved in a good and permanentmanner unless the basic guidelines in the urban planning areadopted and the facilities for public purposes are built, meaningfirst of all the market and similar facilities for public use.The good location of such facilities changes the whole conceptof the urban traffic flows and the co-ordinated planning resultsin permanent and good traffic solution of the whole traffic networkof Kutina.In order to harmonise the existing condition of the trafficinfrastructure with the current and planned needs of the citizensof Kutina, the social community should cany out detailed traffie research and insure adequate financial means for this purposefrom the budget.
Tonči Carić, Senka Pašagić, Zdenko Lanović
2004 (Vol 16), Issue 1
The Vehicle Routing Problem cannot always be solved exactly,so that in actual application this problem is solved heuristically.The work describes the concept of several concrete VRPmodels with simplified initial conditions (all vehicles are ofequal capacity and start from a single warehouse), suitable tosolve problems in cases with up to 50 users.
