Using the data collected by the Universal Postal Union, thepaper studies the con·elation between the delive1y time of ordinarymail items by air and the geographical distance. lt is foundthat there is poor linear co'elation. The reasons for the obtainedresults are discussed and a suggestion for improvementis offered, which would mean improvement in the quality of theconsidered postal service.

Roads are one of the main factors which influence roadtraffic safety. They influence the time of the realisation and thecosts of the transport itself by their technical and exploitationcharacteristics. The right selection of a street will highly affectthe costs of transport that can be reduced, and the speed ofrealisation that can be increased. The paper presents one of themethods of recognition of forms which is later on also tested onan example of selecting the type of the street. The aim of this paperwas to show the possibilities of using the recognition offorms in the traffic and transport system. This way of selectionand classification is needed when it is necesswy to decide fastabout the direction of movement, particularly in special circumstances.

The function of transport is to bridge the distance betweenthe producer and the consumer at the lowest possible price. Anyway in which transport costs can be reduced has to be welcomed,either through introduction of a means which correspondsclosely to the needs of transport service users (more convenient,safer, more reliable, faster transport), or a meanswhich is less expensive to provide, and its function regardingeconomic aspect can also be efficient and reliable.

Mobile telephony appeared in 1955 and its development inthe world and in Croatia can be divided into two generations:analogue mobile system and digital mobile systems. Mobile te/eplzony is a part of the telecommunication market experiencingthe fastest growth. Already in 1990, the mobile telephonesaccounted for 4% of the world market in telecommunicationservices, and their share is increasing daily. Liberalisation ofthe Croatian market of mobile telephony was a necessity for establishingcompetition as a necessG/y prerequisite for providinghigh-quality se1vices and reducing their prices, and it COJTespondsto the mobile telephony system development worldwide.At the beginning of the 90s, the Republic of Croatia was laggingbehind the telecommunication-developed world, and today shehas a modem infrastructure that supports highly sophisticatedse1vices by two digital and one analogue mobile telephone network.

The design of intermediate shaft with axially movablesplined joint must be adapted to the variable position of theshaft axis, i.e. to the change of the joint angle during operation.This design is also used for the reduction of axial forces whichare caused by inaccuracy in the production and assembling ofC(ll·dan mechanisms. The axial force which is generated by frictionof contact swfaces in the splined joint is the function of themagnitude of the transfeJTed torsion moments, splined dimensions,lubrication conditions, and materials used for contactswfaces. It will cause additional bearing loads at cross journalsand in the shaft supports, as well as unallowed vibrations andnoise during operation, thus affecting the safety and lifetime ofthe Cardan mechanism. The theoretical and empirical analysisof Cm·dan mechanisms, which have been studied with andwithout axial forces in the splinedjoint and its effect on durabilityof mechanism elements have been presented.

The port of Rijeka, as part of the future system of the NorthAdriatic ports (Koper, Trieste, Rijeka) plays a significant role infreight transportation towards the Central European region. Bycons/meting the Danube - Sava Canal from Vukovar toSamac, by canalising the river Sava from Samac to Sisak, andby good railway and road connections that will be realised inthe first two to three decades of the third millennium the port ofRijeka will receive the key role in the development of the NorthAdriatic ports. High-quality railway and road connections betweenthe port of Rijeka and /stria, Koper and Trieste, will providemajor possibilities of rationalising the transportation processfrom the port of Rijeka towards the Danube region and theCentral European countries.

The liability of air carriers in international air traffic is stillregulated by the Warsaw Convention from 1929and its amendments.In 1999the Montreal Convention was accepted, whichcompletely substitutes the rules contained in the Warsaw Conventionincluding all its later amendments, and the most importantmodifications have been made regarding the air can·iers'liabilities in case of passenger injury or death on intemationaI flights.