International Conference on Applied Internet and Information Technologies, 2018 DOI:10.20544/AIIT2018.P21 Software Solution for the Calculation of Critical Load Points for Special Consignments Gordana Jotanovic*, Zeljko Stojanov**, Mirko Stojcic*, Goran Jausevac*, Mladen Kuravica*** * Faculty of Transport and Traffic Engineering, Doboj, Republic of Srpska, Bosnia and Herzegovina ** University of Novi Sad, Technical Faculty "Mihajlo Pupin", Zrenjanin, Republic of Serbia *** Republic of Srpska Railways A.D Doboj gjotanovic@yahoo.com, zeljko.stojanov@uns.ac.rs, mirkostojcic1@hotmail.com, gjausevac@gmail.com, eremijamilan5@gmail.com Abstract - The calculation of critical points of special consignments during transport in most cases is counted manually. Usually it is a job that requires several hours, in some cases even days of work. In order to simplify and shorten this long- and long-term work, the software solution "Calculate critical points" is proposed for the calculation of the critical points of the shipments. Key words - Subscribe consignments, transport of special consignments, critical point of the load, software solution. I. INTRODUCTION Safe railway transport means safe passage of traffic composition under overpasses, tunnels, etc. This situation requires accurate and fast calculation of the critical load points of special consignments. Critical load points for special consignments are still counted manually at ŽRS A.D. Doboj, and according to their findings, it takes several hours. This is the job of the Construction Service, which belongs to the Construction Department. The time required by that service to examine the possibility of transporting special consignment ranges from 5 to 20 days. Time depends on the complexity of the consignment. Such a long period of time required to examine the possibilities of transporting the railway becomes uncompetitive on the market, because it becomes unacceptable for the user to wait 10-30 days (in exceptional cases) for the transport. A. Special consignments Special consignments include vehicles whose loading, transport, transshipment, unloading, causes difficulties with respect to installations or railway means of transport, and which can be received for transport only under special technical and operational conditions. Special consignments can be grouped into 9 groups, as follows:  special consignments exceeding the factory profile,  special consignments exceeding the allowed load,  on-wagon consignments without the RIV mark, as well as new vehicles not yet fitted into the rolling stock of a railway,  goods that require special measures due to the position of the center of gravity,  freight rail and steel or concrete structures over 36m long,  wagons with more than 8 axles,  special consignments of goods loaded on two or more wagons,  Individual items whose weight is over 25t. All consignments that must be transported under special technical or exploitation conditions shall also be included in the special consignment. II. TESTING THE POSSIBILITY OF TRANSPORT OF SPECIAL CONSIGNMENT In the case of local traffic, the examination of the possibilities for the transport of a special consignment is performed by the railway transport company (RTC) on whose territory the consignment is transported. Within the ŽRS A.D Doboj, the exploitation sector (transport and transport service and technical service), the construction sector, the electro technical sector and the traction sector are engaged. The request comes first to the exploitation sector (transport and transport service) where its processing and recording is done. After that, it is handed over to the department for jobs (civil service), which is conducting additional tests. In practice, the electrical and technical services sector is engaged as needed. The results of the tests carried out in these sectors (services) are returned to the TTS (Traffic and Transport Services) sector. The TTS prescribes the necessary traffic and technical measures of conditions, and based on them, the economic conditions (price) are required from the sector for railway commercial operations. After that, the TTS informs interested units on the field. Examination of the possibility of transporting a particular consignment is carried out in several stages:  choice of wagon,  check of allowed load,  determining the center of gravity of cargo on the wagon,  determining critical points for consignments that engulf the free profile, 99