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The port shunting yards are developed inside the area of the ports. The main activities are to receive the freight trains from the hinterland, to shunt the freight wagons according to their final destinations from the area of the port, to receive the wagons from maritime terminals, to accumulate wagons according to their destination, and to depart the freight train to the hinterland. So, it is important for port administration to have good methods to evaluate the transit capacity of port shunting yards. A feasible method is to use the discrete simulation model. In our paper, we develop one of this taking into consideration the input flow characteristics of freight trains from land network, the input flow characteristics of freight wagons from maritime terminals, the number of tracks in a port railway station, the technology used for separation of freight wagons on destinations (inside the port or from hinterland), and the duration of technological processes. From the results, we extract the values of trains and wagon sets that transit through the main areas of the railway station (Receiving Tracks, Hump(s) and Departure Tracks).

The recent emergence of bad events (fires, terrorist attacks, etc.) resulted in a large number of deceased and injured people, brought to the attention of specialist’s problems and caused by the lack of adequate dimensioning of access and transit path. In the case of urban transport terminals linking rail lines, metro lines, and surface public transport lines there are a number of specific aspects such as the transport means arrival after a fixed schedule, group acces within the terminal, long waiting time in the terminal etc. In this case the use of a discrete simulation model allows the evaluation of the use of access gates, transit times, etc. In this paper, a simulation model is developed for a hypotetical passenger terminal using the topology of the main Romanian train station. The obtained data can be used for the optimal dimensioning of the number of access gates, of the stairs, of the waiting area etc.

Seaports are multifunctional socio-economic spaces that provide a wide range of services and serve a wide range of customers including shippers, forwarders, logistics operators and transport companies. One of their main tasks is to facilitate the domestic and international trade of goods. The paper attempts to highlight the major role that ports have in the transport system together with the minimization of the transport costs. Ports provide a crucial interface between land and sea. Ports, as integrated logistics centers and multifunctional socio-economic spaces, are key components of the European and global transport system. They also cover transport, logistics, distribution and space functions that influence the city development. Port improvement plays a major role in reducing the transport costs. In order to reduce transport costs, we need to identify the necessary changes to the system (additional berths, reducing the service time by upgrading the operating facilities etc.) to reduce the penalties. Most often, in order to minimize costs, the economic function (sum of waiting costs) have to be optimized. A useful tool for approaching port optimization problems is provided by the theory of queuing: ships can be regarded as "customers", while the "service stations" can be represented by the berths of a seaport. In the case of transit storage, the transfer of goods between sea and land transport is not a single-stage process. In these circumstances the optimum number of berths should be replaced by the optimum number of cranes and the optimum area for transit storage. However, in the hypothetical case study from the paper we will consider the case of a single-stage and single-channel facility (one berth) in order to reduce the queuing time. The main conclusion from the analysis is that the expected queuing time may be reduced either by increasing the handling speed or by making ships more homogeneous (by specializing in serving a particular type of ship or cargo).

The urban transport models are used in the development of Sustainable Urban Mobility Plans. These models are designed to reproduce the actual traffic flow on transport network infrastructure and to test and evaluate the solutions that will lead to a sustainable mobility. One of these solutions is represented by the development of park and ride facilities, for users that are coming from extra urban area. The authors propose in the paper an algorithm for traffic allocation when are developed park and ride facilities. The initial data are obtained from a classic four steps model and are processed to evaluate the degree of demand of transport network when a multi-stage phased scenario is pursued. The results obtained with the proposed method are useful for local and regional decision makers to conceive a strategy to develop new park and ride facilities as well as to obtain a series of quantifiable results for transport network users.

Summary. This paper provides an overview on the ACROSSEE project (funded by the ERDF under the SEE program), its objectives, general methodology, and the main results. Moreover, the main survey results are presented as they relate to the Romanian road and rail border-crossing points (BCPs) with the Eastern neighbourly country, Moldavia. Results include the actual status of the road BCP, surveys on exiting and entering traffic flows, answers to specific questionnaires of the truck and car drivers in relation with origin-destination of the trips, average waiting time in queue and time required for procedures and controls. Discussion on the mathematical modelling is presented and a provisional simulation model is developed, using ARENA software. The early results are used in order to introduce the need for future assessment of the transit time in a road BCP, with the main purpose: the substantiation of the strategic and operational actions for improvements in trade and transport crossings of the EU borders, considering the need for more vigilant and less time-consuming checks at the outside borders of the EU.

In this paper it is developed a location model for the infrastructures dedicated to non-motorized movements by bike in Oradea city, using ArcGIS geographic and information system [3]. They are taken into consideration the movements made by the target people – alternating movements (from home to school) and optional movements (made for recreation), the densities in residential areas, the type of the city arteries and the mobility need of the target people (in this case – young people aged between 15 and 25) in order to design two structures of the transport infrastructure networks (one for the alternating movements and the other for the optional movements), structures which will be realized on the actual frame of the existing transport infrastructure in Oradea city. Using Dijkstra algorithm, the minimal routes for the movements related to the alternating mobility, but also for the movements specific to the optional mobility are determined. Further on the most used arteries in the two structures of urban infrastructure networks are determined. The paper suggests as a solution the structure of the network for the non-motorized movements and also those arteries that must be used for its development, that guarantee gains for the target people (time), for the main operators who exploit the motorized systems, for the local budget of the local municipalities (less funds to sustain the public services) and especially for the environment and people’s health (attenuation of noxious and phonic pollution, reduction of the accidents’ number and health improvement).

Warehousing enables the consolidation of shipments to clients by assembling full truck loads from goods stored in warehouse or distribution center. Storage can be efficiently replenished by ordering full truck loads from suppliers. In order to reduce freight storage and handling costs from distribution centers, cross-docking technique represents a logistic solution which is more and more used. Thus, the optimization of simultaneous unloading/loading operations constitutes an important issue for the distribution center owner/administrator. This paper presents a model based on genetic algorithms optimization techniques for solving the problem of unloading/loading ramps allocation. The efficiency of a cross-docking center is conditioned practically by finding an allocation and an optimal arrangement of ramps. This implies the allocation of destinations to unloading/loading ramps of distribution centers to minimize the total distance performed by the the cargo handling equipment. The case study presents a cross-docking platform with single handling equipment which is assigned to 10 unloading/loading ramps. By applying the solution of the ramp allocation generated through simulation, the total distance performed by the handling equipment is reduced which means lower handling cost for the distribution center owner/administrator.

One of the most frustrating problems when dealing with risks it’s that they come in so many different forms. They can appear at any point in a port logistic system, they can interrupt the supply of raw materials or products, they can cause demand fluctuations (peak or collapse), inventory problems (lack or crowding), dispatch delay. Risks can range on a scale from small delay to a natural disaster, from short term to a permanent damage, with effects localized on a part of a supply chain or affecting the whole chain activity. The risk management allows port administration to take appropriate measures to reduce the consequences of a risk, to provide a good reliability of the logistic system or to design a resilient one. The paper investigates the major risks in port logistics and adequate measures to minimizing their effects. A risk management tree is set-up. Using computer simulation modelling, a case study investigates the port logistic system behaviour under different risk scenarios and evaluates the reliability of the system and its resilience. The operation capacity for different port logistics sub-system is assessed taking into consideration the required operating standards and the measures of performance (e.g. waiting time for vessels and transport vehicles, storage area and time for commodities) of the logistic system are computed.

The identification and the assessment of the risks faced by logistic chains involving the transport of containerized dangerous goods with a maritime component, have a special attention from the specialists in the field because of the share of the containerized transport in the maritime transport.

It is of great importance to examine all interactions between ports, terminals, intermodal transport and logistic actors of distribution channels, as their optimization can lead to operational improvement. Proposed paper starts with a brief overview of different goods types and allocation of their logistic costs, with emphasis on storage component. Present trend is to optimize storage costs by means of port storage area buffer function, by making the best use of free storage time available, most of the ports offer. As a research methodology, starting point is to consider the cost structure of a generic intermodal transport (storage, handling and transport costs) and to link this to intermodal distribution patterns most frequently cast-off in port relationship to hinterland. The next step is to evaluate storage costs impact on distribution pattern selection. For a given value of port free storage time, a corresponding value of total storage time in the distribution channel can be identified, in order to substantiate a distribution pattern shift. Different scenarios for transport and handling costs variation, recorded when distribution pattern shift, are integrated in order to establish the reaction of the actors involved in port related logistic and intermodal transport costs evolution is analysed in order to optimize distribution pattern selection.

Sea ports are important nodes in the supply chain, joining two high capacity transport modes: rail and maritime transport. The huge cargo flows transiting port requires high capacity construction and installation such as berths, large capacity cranes, respectively shunting yards. However, the port shunting yards specificity raises several problems such as: limited access since these are terminus stations for rail network, the in-output of large transit flows of cargo relatively to the scarcity of the departure/arrival of a ship, as well as limited land availability for implementing solutions to serve these flows. It is necessary to identify technological solutions that lead to an answer to these problems. The paper proposed a simulation model developed with ARENA computer simulation software suitable for shunting yards which serve sea ports with access to the rail network. Are investigates the principal aspects of shunting yards and adequate measures to increase their transit capacity. The operation capacity for shunting yards sub-system is assessed taking in consideration the required operating standards and the measure of performance (e.g. waiting time for freight wagons, number of railway line in station, storage area, etc.) of the railway station are computed. The conclusion and results, drawn from simulation, help transports and logistics specialists to test the proposals for improving the port management.

An intermediate hub might increase the accessibility level of ports but also hinterland and so it can be considered more than a facility with a transhipment role. These hubs might lead to the development of other transport services and enhance their role in gathering and covering economic centres within hinterlands and also getting the part of logistic facility for the ports, with effects on port utilization and its connectivity to global economy. A new location for a hub terminal leads to reduced transport distances within hinterland, with decreased transport costs and external effects, so with gains in people's life quality. Because the production and distribution systems are relatively fixed on short and medium term and the location decisions are strategic and on long term, the logistic chains activities location models have to consider the uncertainties regarding the possible future situations. In most models, production costs are considered equal, the location problem reducing itself to a problem that aims to minimize the total transport costs, meaning the transport problem. The main objective of the paper is to locate a hub terminal that links the producers of cereals that are going to be exported by naval transportation with the Romanian fluvial-maritime ports (Galaţi, Braila). GIS environment can be used to integrate and analyse a great amount of data and has the ability of using functions as location - allocation models necessary both to private and public sector, being able to determine the optimal location for services like factories, warehouses, logistic platforms and other public services.

The Romanian capital market is still an emergent one. Following the mass- privatization process and the private investments, three of the most important handling and storage companies acting in Constantza Port (OIL Terminal, Comvex and SOCEP) are listed on Romanian Stock Exchange. The paper investigates their evolution on the market, identifying the expected rate of return and the components of the shares risk (specific and systematic). Also, the price evolution could be analyzed through the informational efficiency which instantly reflects the price relevance. The Jarque-Bera normality test regarding the shares return rate distribution and the Fama test for the informational efficiency are completed for each company. The market price model is taken into consideration for price forecasting, computing the return rate auto-correlations. The results are subject of interpretation considering additional managerial and financial information of the companies' activity.

The concepts of reliability and vulnerability are quite important in assessing the ability of transport networks from land to provide continuity in operation tacking in consideration the relation with seaports. Transport infrastructure modernizing and extension according to land use and sustainable development requirements still represents a challenging issue among policy makers, regional/local communities and scientists. The interest for the researches reliability and vulnerability for transport networks who connect maritime ports with interior city's is generate by the natural disasters, the terrorist acts, unconventional war, etc.. Transport network modelling enable the development of mathematical models used in evaluating the reliability and vulnerability. Nodes or link disruption could have an important impact over transport network users. In our paper we investigates the Romanian road network vulnerability related to Danube crossing versus maritime ports (Constanta and Mangalia) and its mitigation by improving network topology. We use Visum software to promote a methodology to assess road transport network vulnerability versus Romanian seaports and we propose some solutions to reduce probability of road transport network to fail.

Since 1990, in Romania and especially in Bucharest there has been a constantly growing tendency towards new expensive residential settlements located in the suburbs. Following this, even more cars have increased the road traffic towards the city centre. In the last few years, the need to extend the metropolitan area of Bucharest City has become more accepted as a solution to relocate some socio-economic activities. Bucharest is a historically developed city and there is no available space to increase the street capacity for cars and traffic. In this paper, we propose a bicycle infrastructure project to support the sustainable development of the new metropolitan area of Bucharest, and develop a model to evaluate the impacts of such a transport infrastructure on the spatial accessibility of the city centre. We reveal the importance of bicycle parking locations and their integration with urban public transport (subway and light rail). Taking into consideration a natural, native disposition of the younger population to use bicycles, in this way, we will provide quite an effective means of attracting them to non-motorized transportation as opposed to car use.

This paper presents part of the research on traffic risk estimation for Bucharest City area. The aim of our research is to develop complex models as tools of urban traffic risk assessment in planning phase. In this way, several urban planning alternatives could be analysed and evaluate before important transport infrastructure investment are made. The first part of the paper analyses the state of road accidents recorded in Bucharest. The second part of the paper demonstrates how the intersection conflict index can be used in traffic micro-simulation models to assess measures of traffic risk reducing.

Sustainable development is a necessity, solutions for satisfying users’ needs having to be adopted in relation to criteria that often integrate divergent interests of those involved. The optimal location of production centers has the best effect on production costs. The paper focuses on industrial location from the user's point of view, taking into account elements like maximum distance for efficient road transportation, resources proximity and available infrastructure. The developed model has a large scale of applicability in economic sectors like: distribution, automotive industry, constructions. Results of applying this model proved its utility and necessity of further researches on location problems.

The maritime container terminal allows the transfer of container flows from maritime vessels to the land transport network and vice versa. The transit capacity through the terminal is affected by the handling capacity of the equipment at the terminal, by the size of the storage areas and least by the technologies used in handling and storing the containers in the terminal. In this paper, the influence of these last two technologies on the duration of the process of unloading/loading of sea vessels within the terminal is analyzed. A discrete simulation model is used to evaluate the sizing method for short-term storage area located on the dock. The manner of allocating the flows of containers on it, as well as the working technology of the handling equipment, have an influence on the number of containers taken over, respectively loaded on the maritime vessels. The simulation model topology is developed following the existing physical structure of a container terminal from Constanta Port, in Romania. The obtained results can help the administration of the container terminal in optimizing the activity of handling, storing, and transferring the flows of containers from the maritime environment to the mainland and vice versa.