The importance of freight transport for today's society neednot be underlined. Yet, rather few attempts have been made inorder to model freight transport demand in a quite 'original'and appropriate way, especially if the literature on freight transportis compared with lhe huge amount of works done on passengertransport.The aim of lhe paper is twofold: firs/, a seleclive survey isconducted on the issue of freighttransporl demand modelling,also from an 'evolutionary' standpoint; second, such a body ofliterature is arranged in order to provide an original classificationof available models.

The paper analyses the statistics of vehicle anival at a selectedintersection in the city of Zagreb. The intersection has allthe elements of movement: going straight, left turns and rightturns. The statistic analysis in this work is based on the measurementsearned out by means of a device for gathering informationon traffic, HI-STAR Model NC-90A.We have shown that four days (Monday - Thursday) havethe same statistical regularity. Two inte1vals have been isolatedin which normal distribution can be accepted: one from 6 a. m.1012 noon and another from 1 p.m. to 4 a. m. The period from6 a.m. to 12 noon has Gauss distribution with the expectedpeaktrafficdensityalft = 9.9o'clock (i.e. atsixminutestoteno'clock) and standard deviation a = 3.1. The periods from1 p.m. to 4 a. m. have Gauss distribution with the expected peaktraffic density at fA. = 15.6 o'clock (i.e. at twenty-four minutes tosix p.m.) and standard deviation a = 4.2. The results can beused for traffic regulation at that intersection i.e. for the trafficsignal control of the intersection.

The paper analyses the urban motorway, the Ljubljanskaand Slavonska Avenue in Zagreb. As the key road, it is importantfor the city of Zagreb both regarding internal and externaltraffic links. The almost ideal location of the Ljubljanska andSlavonska Avenue has not been properly evaluated and used bythe Zagreb urban and traffic designers. The traffic count, measuringthe vehicles speed and the analysis of the existing interchangeshave indicated the disadvantages, drawbacks and irregulalitiesrelated to the design of the motorway. The measuresfor improving the traffic flows and change of signalling deviceshave been proposed and the design of interchanges has beenrecommended. The traffic forecast for the next ten years, accordingto the growth predicted by BDP, imposes urgency in realisingthe phases in improving the throughput capacity andsafety of the traffic along this motorway.

Considering previous calculation of vehicle speeds negotiatingcwvcs, in this paper we are trying to define and detenninelateral accelerations which occur when a vehicle negotiates acun1e. We have also analysed how the speed of negotiating acwve influences the braking force, which is in many traffic accidentsthe cause of the accident, if the braking system is not adjustedto the speed (and vice versa).

Paper deals with conceptual guidelines of national air trafficdevelopment from the point of view of safety and shows thenecessity of creating a national safety program.Requirement of safety program implementation is the foundationof national aviation safety board, which should be operatedindependent of civil aviation authority. The main tasks ofthis board are accident and incident investigations, data analysisand suggesting of safety recommendations and standards,i.e. prevention programs. The next premise of safety programmodeling is to reach the legal and administrative considerationsfor introduction of incident reporting system on confidentialprinciples. The application of the model of safety programin Croatian air traffic is closely related with implementation ofEuropean aviation normative.

The article describes the project of the Adriatic Corridor,analysing the European and Italian framework in which itcould be collocated, the planned structure of the Corridor interms of geographic extension and infrastructure elements, themain objectives of the project, the works that it includes, thepresent obstacles to its development and, finally, the presentand future freight and passenger transport demand in the areacovered by the Corridor.The realisation of the Adriatic Corridor is considered strategicin order to contribute to achieving the main objectives ofthe European transport policy: the territorial and economic cohesionof the EU Countries, the development of the trade withthe non-EU regions and a sustainable mobility.

A whole range of dangerous substances and harmful organicand inorganic materials are transported daily through thesystem of traffic and tourist environment and flows. The use ofthese substances covers a wide range: in the production ofdrugs, agrotechnical protective means, fertilisers, paint and varnish,po(vmers, detergents, fuel, and in other industries.Within the strategy of environmental protection and thetourist and traffic surrounding, the producers and traffic societiestake relatively good care about the so-called technologicalsafety during the production, handling and transport of thedangerous substances.According to the legislation, the obligations accepted fromthe Base{ Convention, and conclusions of the United NationsConference on Environment and Development (UNCED) etc.,the elimination of the harmful ma ller and waste from the Croatianecological environment has a strategic objective, althoughthe necesswy protective measures have not been unde1takenand organised completely yet, just as the knowledge in case ofmajor accidents with dangerous material has not been acquiredyet.In the transport environment and the tourist flows it is necessaryto strengthen the control of selection, development andintroduction of the technologies that include dangerous substances.On the other hand, the technologies that represent anexcessively big risk regarding accidents, with the possibility ofendangering the inhabitants, goods and eco-environment,should be strongly opposed to.

This paper describes the criteria, standards, and engineeringprocedures used to design principal elements of the highwayalignment, highway cross sections, and adjacent roadside environment.Development of a comprehensive highway design focuseson the establishment of travel lane configuration, alignmentlocation, and all dimensions related to the highway crosssection. A three-dimensional physical location is determinedthrough calculation of a horizontal and vertical alignment ofthe highway centerline, based on a variety of operational considerations.The results of these activities are refe'ed to as thegeometric design and represent all the visible features of a highwayor street. The first and major portion of the paper deals withthe design of motor-vehicle facilities. Specific design elementsare described and discussed with respect to design methodology.

Call centre largely came into being as a result of consumerneeds converging with enabling technology- and by the companiesrecognising the revenue opportunities generated by meetingthose needs thereby increasing customer satisfaction. Regardlessof the specific application or activity of a Call centre, customersatisfaction with the interaction is critical to the revenuegenerated or protected by the Call centre. Physical(v, Call centreset up is a place that includes computer, telephone and supervisorstation. Call centre can be available 24 hours a day - whenthe customer wants to make a purchase, needs information, orsimply wishes to register a complaint.

Analyst motivation is to develop team work with forwarderand his principal in order to realise effective communicationbetween forwarder and principal, according to the set problemsand limitations directed by the surroundings in the system of internationalforwarding agency, foreign trade, traffic and informationsyscems.The analyst cares for personal and collective motivationdevelopment, creating convenient conditions of team work offorwarder and his principal in order to model the process anddata in the most creative way using the Stntctured SystemsAnalysis method. By applying this method, the analyst createscomplete documentation of the process model: Functional DecompositionDiagram, Context Diagram, Data Flow Diagramof other levels of abstraction, logic process definition, and descriptionof data flow structure and description of data bufferstntcture.The team tries to achieve the optimal diversity with definitegoodwill of analyst, forwarder and principal, and diverse characteristicsof personality, professional knowledge and balanceof all members.

This article describes the basic technology of satellite .I)'Stemsrelated to the geostationary satellites particular(v with regardto the .)'Stem of satellites in the European network ofEUTELSAT (European Telecommunications Satellite Organization)covering Europe, North Africa and part of the MiddleEast.This enables positioning of vehicles in the internationalroad transport system in the territory which has been covered bythe satellite signal.The EUTELTRACS system within the EUTELSAT organizationenables not only positioning with preciseness ofabout 300 m, but also two-way communications between vehiclesand company headquarters, which is an advantage comparedto the other positioning systems.EUTELTRACS service belongs to the land mobile satelliteservices with secondary status (it must not impose any interferenceto other radio-communication services and cannot claimprotection from other services).The use of frequency bands is for the up-links 14.0-14.25GHz, and for the down-links 10.25-11.20 GHz, 11.45-11.70GHz and 12.50-12.75 GHz.The EUTELTRACS system provides services by means ofOmniTRACS terminals and CEPT (European Conference ofPostal and Telecommunications Administrations) administrationsissue type approvals, designating the terminal markingand make decisions regarding free circulation of terminals inconformity with their national regulations.The OmniTRACS terminal.l)'stem has been specially presentedas well as the fixed part of EUTELTRACS .)'Stem withthe satellite segment.Every transport company has been considered as a subscriberto an authorised EUTELTRACS service provider.The service for tracing trucks in the international trafficthroughout Europe and Middle East can be fully expressed byincluding the stronger transport companies (more than 10trucks) which can establish the transport more rationallythrough EUTELTRACS service.The implementation of the EUTELTRACS service hasbeen imposed on the Croatian companies, whose internationaltransport could be well developed.Croatia has been a member of the EUTELSAT organisationsince December 1992, and this has provided the basic conditions for organising this service. The service provider canbe the acting telecommunications operator, in this case theCroatian Post and Telecommunications (HPT), or any othercompany in co-operation with HPT (leasing the telecommunicationslines, tariffs, maintenance etc.).The article presents the possibility of implementing theEUTELTRACS service in Croatia with the responsibility of theservice provider to establish connections between any dispatchcentre in Croatia by means of Croatian telecommunicationsnetwork, and through international network to the HUB stationand the corresponding geostationary satellites, includingthe accounting matters.It also presents the usage of the computerised road maps foraccurate vehicle position-plotting and free circulation for OmniTRACSterminals.

Regarding characteristics of transportation exchange andthe problems of subjects active in this market, the paper considersthe possibility of qualitative improvement through organisationof business on the exchange principles. Since the level ofbusiness operation in the transportation exchange influencesdirectly the development of the transportation, any improvementin this sense has its positive effects on the functioning ofthe traffic system as a whole.

The road regulations and traffic signs, as we know them today,are not older than a hundred years. When the first motorvehicles appeared on the roads, passing the state borders evermore frequently and easily, and that was at the beginning of the20'h century, the need arouse to detennine international regula tionsthat would hannonise the infOJmation on all the roads.This paper presents the historical development of the trafficsigns.

Besides the trade flow, the Port of Koper, as an organisationalfonn of co-operation between parties offering transportservices, needs also the infonnation flow in the area it covers.The article shows the possibility of graphic presentation ofthe Port transport and logistic infrastructure and the graphiccommunication between all the users of the Port area. The intranetconnection gives every user the insight into the systemwhere all the requested data for an efficient exploitation of a detenninedinfrastructure are available.The possibility of applying the intranet connections in thewhole operating system of the enterprise offering port services isillustrated in the conclusion.

The access to a single vertex of the non-directional transportationnetwork graph can be defined in various ways, but ifwe want to classifY the vertices and at the same time avoid ambiguity,then each of them has to be assigned a certain number.The paper uses the method for detemzining the access to a singlevertex based on the description of the transportation networkusing the symmetrical matrix of incidence. By knowingthe matrix of incidence it is possible to detemzine the eigenvaluesi.e. eigenvectors, and their comparison detemzines the valuesfor single vertices. Apart from describing the method, theconcrete example of the tram network of the city of Zagreb hasbeen analysed. Based on the obtained analysis results, it is possibleto detemzine the efficiency of connecting single vertices inthe considered transportation network, i.e. to propose its improvements.

In view of the fact that there are different approaches tostudying traffic in states of emergency, this article discusses oneof the possible approaches to research of global standpoints inthe analysis and assessment of the factors of exposure, menace,level of risk and danger of traffic systems in states of emergency.

About 50% of the analyses of actual road traffic accidentsare the analyses of various collision conditions of vehicles, i.e.various collisions of two vehicles or crashes of vehicles intovarious types of solid barriers. Such analyses, however, requirethat the values of vehicle post-collision movement parametersof its kinematics are determined with as much accuracy as possible.Since methods commonly LLSed in the present forensic expertisedo not provide satisfactory results by not taking into accountall the elements of the vehicle movement, this paper presentsanalytic considerations of the issue, thus determining relativelysimple and for the practice acceptable analytical expressionswhich can be LLSed to detennine the vehicle movement parametersimmediately following collision.

Postal administration world-wide is improving the postaltraffic also by introducing modem automation throughout itsoperation in mail transport.The Croatian Post must also carry out this demanding andchallenging project which must necessarily be well planned andimplemented as soon as possible. The automation of the operatingprocedures in the technological phases of mail-piecestransmission provides a significant substitution for the slowand expensive manual work, resulting in substantial reductionof costs, rise in the quality level of services and cutting down ofthe time-limit control of transmission.This is the aim of this article, as preliminary communication,which is based on the carried out research regarding importanttraffic parameters in the post centre Zagreb, as the largestone in Croatia. The results can also be used as adequate referencefonn for the research in other post centres ofCroatia. Afterthese studies and the obtained relevant infonnation, amethod of designing new rationally organised postal network ofCroatia in all segments of mail-pieces transmission would follow,as well as fanning of a suitable postal code and developingof the Croatian postal code map. This comprehensive workpresents the preparation phase of the project and it is absolutelynecessary for the success of the general automation in the Croatianpostal traffic.

In radio network planning, the goal is to specify optimalbase station locations, service areas, antenna patterns and handoverstrategies for a given mobile radio system. The system performanceis fixed and the radio channel is subject to optimisation.Network planning requires channel characteristics thatprovide information about the expected sendee quality, especiallythe outage probability. The channel description must onlyperform as a qualitative measure of an actual receiving area.Power delay profiles are a convenient and very common descriptionof channel time dispersion, which can be easily physicallyunderstood as footprints of individual reflected or scatteredpaths, and provide a capability to a network planning engineerto discover areas of heavy time dispersion and importantscattering regions on the terrain. This in turn enables better assessmentof base station sites, antenna pattern selection, sen,iceregion (cell) shaping (handover criteria) and solving networkproblems.Time dispersion is mostly found to be the cause of poor coverageby excluding other possible causes. In cases where fieldstrength coverage does not overlap and base station sites cannotbe moved, shaping antenna directivity will be the only way toeliminate excessive time dispersion.

Aeronautical Public Correspondence (APC) is a telecommtmicationsse!Vice, which enables passengers onboard aircraftto make telecommunication calls to people on the ground.This article describes the terrestrial communications seiVicewhich is based on cellular network for the European CEPTmember countries (CEPT- European Conference of Postaland Telecommunications Administrations) named TerrestrialFlight Telecommunications System (TFTS).This system is a Pan-European System, which means theusage of hannonised frequencies in Europe with hannonisedstandards for the TFTS equipment, which have been issued bythe European Telecommunications Standard Institute (ETSI).Frequencies allocated for TFTS have been designated bythe World Administrative Radio Conference, WARC-92 withfrequency bandwidth of 2x5 MHz:1670- 1675 MHz, for ground to air1800- 1805 MHz, for air to ground.TFTS planning is perfonned by the application of frequencyblocks (42 blocks) with 164 channels in total. Bandwidthof each radio channel, which contains 4 speech channels,is equal to 30.3 kHz.Due to the very high flight of the aircraft (about 13,000 m),it needs a long distance between the centres of cells (radio stationon the ground) to avoid the eo-channel or adjacent channelinteJference.The article presents the planning process with typical cellradius of240km or 350km. In the viewofthatfact, the need ispointed out for finding a compromise solution with regard toemitting power and the influence of interference.Final(v, it is noted that TFTS ground radio stations inCroatia, which are located in Zagreb and Split, may cover theterritory of some neighbouring countries other than Croatia,which is important from the commercial point of view.

The geo-traffic advantages of the Republic of Croatia havenot yet been evaluated as a whole. The traffic-maritime valorisationis included in the strategy of long-term development ofCroatia. This particularly implies the constntction and modernisationof the sophisticated railway and road traffic routesconnecting the Danube region and the Adriatic, especiallyalong the transversal corridor the Danube region - Zagreb -Rijeka - maritime markets, and then towards other maritimeand river ports. At the same time, the application of these technologiesshould be reconstntcted longitudinally from the Westto the East. The container and piggyback terminals and cargotransport centres (RTC) should be primarily constructed, regularcontainer and piggyback trains established and connected,by sea ports and shipping, first of all through the port of Rijeka,with various maritime markets.In this way, higher rationalisation would be achieved, firstof all in traffic, then in economy and the community as a whole,with a far greater traffic safety, environmental protection, majorforeign exchange inflow, etc.

Incomplete combustion process is a potential source ofbenzo(a)pyrene (BaP) and tetrachlorodibenzo-p-dioxin(TCDD ). These compounds have been detected in effluents ofmunicipal incinerators, sewage sludge, cigarette smoke, automobileexhaust etc. Although BaP and TCD have carcinogenicpotential, in recent years these agents have received great attentiondue to their environmental persistence and remarkablyacute toxicity.To assess health risks associated with human exposure toBaP and TCDD, it was of interest to evaluate their effects uponhuman polymorphonuclear leucocytes by measuring the releaseof lysosomal and cytoplasmic enzymes.Suspensions of human polymorphonuclear leucocytes(PMNL) were treated with BaP, TCDD and BaP+ TCDD atconcentrations of 1 0·1, 1 Q-6M. These agents provoked a progressivetime- and dose-dependent release of lysosomal enzymebeta-N-acetyl-glucosaminidase and cytoplasmic enzyme lactate dehydrogenase, beta-GLM and LDH respectively. Atconcentrations listed TCDD was much more effective in realisingboth enzymes beta -G LM and LDH than BaP. In the experimentswith the combination of BaP+ TCDD, extracellular releaseof beta-GLM or LDH was significantly higher as comparedto BaP or TCDD-treated samples. lt seems possible thatTCDD affected the solubility of beta-GLM and LDH to agreater extent than the activity of BaP.The observations obtained in these studies suggest that BaPand TCDD damage the lysosomal and cellular membranes.

This paper presents a survey of strong bora wind. Bora windof extreme severity, which may blow along the entire Adriaticcoast, usually causes a lot of damage to the electrical power networkand a complete road and sea traffic disruption. Therefore,there is a growing need for introducing the bora risk factor intraffic planning.

Knowledge of traffic characteristics is useful to the highwayengineer in developing highway and transportation plans, performingeconomic analyses, establishing geometric design criteria,selecting and implementing traffic control measures, andevaluating the pe1[ormance of transportation facilities. Doze/ISof measures have been employed to describe the quality andquantity of traffic flow. This paper presents information onthose flow characteristics that fundamentally bear on the planning,design, and operation of highway and transport facilities:traffic speed, travel time, volume, and density.

The construction of the bridge mainland - Krk has integratedthe island of Krk into a unique road traffic system ofRijeka and the Croatian seaside. The bridge, together with theferryboat lines Senj and Baska, have significantly improved thetraffic connections of the islands of Cres and Rab, especiallywith Rijeka and the seaside of the counties: Primorsko-goranskaand Licko-senjska and Istarska zupanija.Apart from the connection of the island of Krk with themainland and the neighbouring islands, also the interurbanconnections within the islands are very important.The development of tourism will increase the significanceof the Krk Airport, especially during the tourist season.

In the past, traffic science did not always have the role andtask in accordance with its needs and abilities.The analyses reveal that scientific research in the field oftraffic has not always been in accordance with its characteristicsand did not app£v an adequate methodology which oftenbrought to suboptimum solutions.Accordingly, traffic science is treated as an independent scientificfield called 'traffic' within technical sciences. Thus,having a definite object of research it would best fulfill its roleand accomplish its task.

The paper presents, in broad outlines, the concept of theFormal Safety Assessment, a newly proposed official methodologyfor the rule-making process in IMO. It examines possiblepotentials and drawbacks of the proposed methodology and attemptsto identify the most important long-term consequencesof its application in the international shipping and shipboardoperations.

The paper presents Slovenian cargo shipping, its system oforganisation, ownership, age and value stntcture. It shows theimportance of shipping in the Slovenian overseas trade and itsimpact on the state's balance of payments. The analysis of thecompetitiveness of shipping was made from the viewpoint ofoperation costs and in comparison with the competitiveness ofEU shippers. The paper concludes with a proposal of possiblesystemic solutions which improve the competitiveness of Slovenianshipping.

A great number of very severe traffic accidents occurs as thedirect result of destabilisation of the vehicle negotiating a curve,most often caused by excessive speed of the vehicle for the givencurve configuration, and for the given surface condition. Therefore,the issue of determing the speed in negotiating curve is notjust a problem met by experts involved in the analysis of the actualtraffic accidents, but also a question without which the preventivesafety measures in road traffic cannot be thought of,both regarding the construction and design of the roads, and regardingspeed limitations at certain points. The aim of this papersis to define a exactly analyticall method for case of actualvehicle negotiating a curve situation.

The article presents a system approach to air traffic operationand control. A mathematical model of the system has beendeveloped, for the case when the input/output functions are discreterandom processes. A solution for a special example of inputfunctions has been calculated and analysed.

Full implementation of the final phase of EATCHIP isplanned for the beginning of the 21' century. It will re-define theEuropean system of air traffic regulation and control. The integrationof a great number of ATC systems into a unique operativenetwork is supported by the technical modernisation andstandardisation of the communication, navigation and radardevices. Integration of Croatia into the European air trafficcontrol system assumes its active participation in the cun·entprojects, implementation of relevant technical standards andthe national air traffic development strategy within the contextof Euro-atlantic integration.

The article deals with the problem of network facilities locationin the low-pressure networks. It is a 'general m-median'problem. The demand of gas is defined both in the nodes andalong the edge. The problem is solved by a heuristic algorithm.It searches for the optimal location of supply facilities in thenetwork using Mini-sum criterion. The continuous demand oneach link is replaced by a concentrated demand in the middlepoint of the link.

Traffic counts or statistical evidence of the traffic processare often a characteristic of time-series data. In this paper fundamentalproblem of estimating deterministic and stochasticcomponents of a traffic process are considered, in the context of'generalised traffic modelling'. Different methods for identificationand/or elimination of the trend and seasonal componentsare applied for concrete traffic counts. Further investigationsand applications of ARIMA models, Hilbert space formulationsand state-space representations are suggested.

The majority of network services provision (postal and telecommunicationsservices, rail transport, air transport, etc.)were traditionally considered as natural monopoly. New scenarioof the liberalised national market and 'Open NetworkProvision' require precise and concrete economic evaluationbefore implementation itselfThis paper considers the methodology for the application ofnatural monopoly with the concept of cost sub-additivity. It ispointed out that the scale and scope economies, associatedwith 'plant (network) sub-additivity' is not sufficient to justifythe monopoly in every service provision in the traffic system andits subsystems. The paper considers and analyses the possiblemarket configuration with various degrees of competition fortelecommunication subsystem. The asymmetric competition inthe telecommunication subsystem by means of the dominantorganisation model has been analysed.

The paper shows the maritime system of the Republic ofSlovenia and its weakpoints, mainly as a result of the transitionand gaining of independence. The second heading describes researchactivities in the area of the maritime system of the Republicof Slovenia during the period from 1992 to 1995. Thethird heading gives a brief review of the EU maritime policy anddescription of Research & Development projects that are intendedas guidelines of the EU maritime policy. In conclusion,the author presents a proposal of the themes and procedures ofscientific research projects in the area of maritime activities ofthe Republic of Slovenia.

The European cities are faced today by the phenomenon ofexpanding everyday activities, affecting directly the traffic development.Physical expansion, the growing number of cars androad networks explain the increase in car utilisation in all typesof travelling in the range of 75 to 90%.Due to the adverse effects on the environment caused bysuch growing motorisation, the efforts are made in order to establishenvironmentally friendlier traffic. The paper considersthe concept of environmentally friendly individual trafficthrough MCC (Micro Compact Car) and MCC- mobility .systemwhich will provide its linking with other traffic participants,which may have a long-term positive influence on the quality ofurban life.

This paper describes the applications of an enhanced neuralnetwork and genetic algorithm for bus tickets sales forecasting.The proposed approach has several significant advantagesover conventional prediction methods. The major advantage ofthe approach is that no assumptions need to be made about theunderlying function or model, since the neural network is ableto extract hidden infonnation from the historical data. Althoughneural networks represent a promising altemative forforecasting, the problem of network design remains and couldimpair widespread applications in practice. The genetic algorithmis used to evolve neural network architectures automatically,thus eliminating the pitfalls associated with human engineeringapproach.

Internet information traffic becomes greater and moreimportant. With increasing growth of information importancerequirement for its security becomes indispensable. Theinformation security problem especially affect large and smallcompanies whose prosperity is depending on Internet presence.This affecting the three areas of Internet commerce: credit cardtransactions, virtual private networks and digital certification.To ensure information traffic it is necessary to find a solution,in a proper way, for three major problems: frontier problem,market problem and government problem. While the eventualemergence of security standards for Internet transactions isexpected, it will not automatically result in secure Internettransactions. In future, there is a wealth of security issues thatwill continue to require attention: internal security, continuedhacking, social engineering, malicious code, reliability andperformance, skills shortages and denial of se1vice attacks.

The paper presents a model of a detector-controlled trafficlight intersection as a complex traffic system. By analysing thekey factors of safety, the preliminary guidelines are given for theimplementation of the presented solution. The special emphasisis on defining the safety intervals as significant safety factorsin passing through an intersection.

The work describes some biologically regenerative fuels andcomments on the possibility of their application. Regarding theEuropean conditions, the most acceptable biologically regenerativefuel has proven to be the one based on rape. The characteristicssignificant for the combustion have been compared tothe conventional (fossil) fuels. Also, the impact of biologicallyregenerative fuels on the emission of harmful exhaust gases hasbeen described, and a favourable influence on the emission ofcarbon dioxide (CO2) and other harmful exhaust gases hasbeen determined.

The paper first describes the invention and introduction ofmobile telephony in the world and in Croatia. Then the basiccharacteristics are compared as well as the possibilities of certaingenerations of the mobile radio telephone systems with emphasison certain advantages. Finally, the prospects of furtherdevelopment of the mobile telephones are discussed, and theadequate conclusions made.

The development of fast railway results in an increased applicationof Trailer Train bimodal system transportation. Thetraffic costs are multiply reduced, particularly the variablecosts. On the other hand the environmental pollution from exhaustgases is also reduced. Therefore, by the year 2010 cargotransport should be preponderant~v used which would be characterisedby fast electric trains producing less noise, at lowercosts and with clean environment.

Air supply can be performed in two ways: by transportingthe technical equipment by transport aircraft or helicopters,and unloading upon landing and by air-dropping. The airdropcan be performed by dropping without parachutes, with parachutesand by low altitude cargo extraction. In the USA- CADS(Controlled Aerial Delivery System) has been developed providingcontrol of the falling cargo via a remote controller.