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This paper investigates the efficiency of different models in shaping the transfer function of port container terminals by coordinating the handling equipment’s activity. Differences in the productivity of the handling equipment and the limited capacity of the storage area at berth generate deadlock situation that could be handle through three correlation procedures: (i) adjusting the productivity to the minimum when the storage area is fully used; (ii) on/off control of the most efficient equipment, and (iii) limitation of the productivity of the most performing equipment. These techniques and the variations in input elements (ships arrival rate, containers number to unload/load, berth storage area) are taken into account for choosing the best strategy of port activity. A simulation model, developed with ARENA software, is created to analyse the port activity. Beyond the analytical models that deal with one ship handling process, the simulation model could take into consideration the process on a period of time, allowing studying the impact of stochastic elements on the process. The model contains the following modules: the vessels arrival, waiting in harbour, anchorage, containers unloading/loading on the vessels, temporary storage at berth, container transfer to inland storage area, and vessel departure. Computer simulations allow analysing random variable of the vessels time spent in port. The mean value should be kept at minimum and thus the best handling strategy could be identified. In addition, the sensitivity of the results according to the variation of the input elements is obtained.

The paper tries to improve the multimodal passenger transport system. The growing demand for mobility has led to the need of finding ways to deal with it. The Authorities should focus on providing an attractive public transport which implies a public transport with sufficient transport capacity and with announced and correlated transport schedules. Transfer time is one of the most important service quality indicator for evaluating intermodal transit system. The paper is making available to decision-makers from transport domain a methodology for correlating both transport capacities and transport schedules, exemplifying it on a case study in Henri Coanda airport. To increase the airport accessibility, the airport Authority depends on other involved organizations like: urban and regional public transport companies; taxi operators; rental car companies etc. The transport options for air passengers from/to home to/from Henri Coanda Airport are: individual long distance modes (private vehicle, taxi); collective long distance modes (bus transport). The paper presents the correlation of transport capacities and transport schedules in Henri Coanda airport considering the air traveler passengers flow

Quality demands imposed to transportation by beneficiaries might be reached in the situation that the transport means that get obsolete with time, are replaced with others to satisfy the need for mobility addressed to the system. Establishing the moment of transport means replacement is an economic equilibrium problem. As time passes, obsolescence arises and maintenance and operating costs rise. They increase until they exceed the acquisition cost of a new vehicle. The research methodology consists in establishing the most appropriate maintenance and operating costs evolution function so that, by finding its minimum and considering the costs of acquiring a new transport vehicle to determine the minimum value of both cost categories. To take into account real situations, calculation encloses an updated value of costs in time. The theoretical considerations are supported by a case study where the economic moment of replacing a transport vehicle is determined for both cases, with and without updating.

The correlations between investments in transport infrastructure and territorial development continue to concern public authorities. They are responsible for optimising the allocation of financial resources, and they are interested in the correct short- and long-term estimations of investments in transport infrastructure’s consequences for development. The direct and indirect effects of transport infrastructure are present in the socio-economic assessment methodologies of projects. Despite the recorded progress, uncertainties remain in technical assessments, especially socio-economic ones, and they do not remove decision-makers’ concerns regarding the necessity and appropriateness of investments. Based on these aspects, this paper aimed to clarify the effects of new infrastructure on socio-economic development.

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.

Impetuous multiplication of mobility and road traffic proliferation lead to concerns for increasing the attractiveness of urban public transport. Compared to private car use, urban public transport attractiveness is conditioned, in particular, by travel times and certainty of respecting the transport schedules, meaning planned traffic stability. Traffic schedules are considered to be more stable as the primary delays from the announced schedule have low probabilities and values and their propagation as repeated delays is least noticed in time and space. Solutions for assuring traffic stability must take into consideration contradictory aspects, because introducing time reserves in the schedules means time travel extensions. In order to assure the stability of planned traffic, present paper develops studies of various models and methods that aim to reduce inherent primary delays. Thereby, for studying repeated delays on a complex network, a mathematical model adequate to a Discrete Event Dynamic System (DEDS), that in MAX-PLUS algebra becomes a linear system, was used. The paper concludes with a case study on an integrated network resulted from the superposition of Bucharest’s existing suburban rail network with the underground network designed for 2030, being identified measures for improving the stability indicators. Traffic stability is assessed on the basis of two indicators: instability coefficient and delay elimination rate. Main measure for improving stability indicators is the growth of time reserves taking into consideration the quality requirements resulting from the condition of maintaining a reduced planned travel time.

The performance of a transport service is measured by its quality attribute, which is the most synthetic and comprehensive indicator. However, it is difficult to identify this service quality attribute because it involves the various customer perceptions and it may be influenced by the passengers’ preferences or by the travel behavior corresponding to a certain social category. The modal split of passenger transport is also influenced by the quality of supplied services which establishes a market share for the transport mode analyzed, in this case the urban public transport. The present paper aims to identify specific indicators for assessing the quality of urban public transport services, and to characterize the performance of the transport supply. It is well-known that a quality service guarantees the success of a public transport operator, with direct implications on user behavior. A case study was carried out, highlighting the compliance of the public transport operator in Bucharest with the traffic program, and an indicator of travel time accuracy was established. Conclusions are formulated in order to improve service quality and, in this way, to increase the attractiveness of urban public transport and the quality of life.

Transport studies are conducted for a better understanding of the actual mobility and for developing transport forecasting models to predict the future transport demand and the changes in travel patterns. Transport planning involves the decision-making process for potential improvements to a community’ s roadway infrastructure. The first transport models used to analyze globally the transport system requirements while nowadays models were rethought as a demand – supply interaction reflecting the correlation between transport and socio-economic development. The transport forecasting methodology use a four stage structure consisting of: trip generation, trip distribution, modal split, traffic assignment. In the second stage of the model, the generated trips for each zone are distributed to all other zones based on the choice of destination. The trip pattern is represented by means of an origin-destination (O-D) matrix. The Growth Factor Model and the Gravity Model are two methods to distribute trips among destinations. The two methods for developing the O-D Matrix are presented and criticized in this paper, showing the similarities and differences between them and highlighting the implications for rigorous determination of future transport demand. A case study is done to emphasize the differences between these models and their implications in carrying out transport studies.

The paper tries to evaluate the influence of the Bucharest metro network development on the urban areas accessibility and to characterize its homogeneity. In the case study the homogeneity index is determined according to which some conclusions regarding the actual metro network situation are drawn. The network poles accessibility was also determined, the quality of service of the inhabitants from the five studied areas being characterized. Some correlations between the accessibility and the population and between the accessibility and the population density were made, some conclusions upon the further network developments being drawn.

This paper presents the authors’ vision about the planning foundation for the new residential areas from the large cities outskirts, in a sustainable development framework. One considers the great generation potential of the high and very high income population in case of the used products with remained reuse value, or new and undesired products, available in the residential places. We propose a space allocation model with a hexagonal hierarchical structure for the centralized return centers in a reverse logistics. The space allocation model for the recovery centers implementation takes into consideration: the recovery habits, environmental care and sustainable development education, “moral” compensations, centralized recovery centers facilities, walking willingness of the average inhabitant of the considered area, decision makings involvement at the local Public Authority level, and local community. One reveals the importance of the data collecting stage for the potential and availability of the exhausted products (having reuse value) in a specific area with high and very high income population

Fulfilling the nowadays population’s mobility requirements is an acute duty that the policy makers, and mostly those from the public transportation field or local authorities, should solve into a sustainable manner. We travel more and for different purposes, with a lot of travel means, proving a selfish travel behavior. The travel pattern, mainly in the cities, has changed dramatically during the last century, and we assist to an exacerbate use of the personal cars instead of the public transportation or walk. The paper investigates the public transportation system in Bucharest area, outlining the way the public authorities decided to shape its development. Different transport modes (subway, bus, tram, trolleybus) are analyzed, considering their network features and technological procedures. Using dedicated software (VISUM), the public transport levels of service for the city’s districts are evaluated. A concordance between the territory system characteristics and the public transport is seek out. Conclusions, to improve the public transport attractiveness and to alleviate the mobility, are proposed.

The transport system is a powerful system with varying loads in operation coming from changes in freight and passenger traffic in different time periods. The variations are due to the specific conditions of organization and development of socio-economic activities. The causes of varying loads can be included in three groups: economic, technical and organizational. The assessing of transport demand variability leads to proper forecast and development of the transport system, knowing that the market price is determined on equilibrium between supply and demand. The reduction of transport demand variability through different technical solutions, organizational, administrative, legislative leads to an increase in the efficiency and effectiveness of transport. The paper presents a new way of assessing the future needs of transport through dynamic series. Both researchers and practitioners in transport planning can benefit from the research results. This paper aims to analyze in an original approach how a good transport forecast can lead to a better management in transport, with significant effects on transport demand full meeting in quality terms. The case study shows how dynamic series of statistics can be used to identify the size of future demand addressed to the transport system.

The significant growth of volumes and distances on road transportation led to the necessity of finding solutions to increase water transportation market share together with the handling and transfer technologies within its terminals. It is widely known that the biggest times are consumed within the transport terminals (loading/unloading/transfer) and so the necessity of constantly developing handling techniques and technologies in concordance with the goods flows size so that the total waiting time of ships within ports is reduced. Port development should be achieved by harmonizing the contradictory interests of port administration and users. Port administrators aim profit increase opposite to users that want savings by increasing consumers' surplus. The difficulty consists in the fact that the transport demand – supply equilibrium must be realised at costs and goods quantities transiting the port in order to satisfy the interests of both parties involved. This paper presents a port equipment sizing model by using queueing theory so that the sum of costs for ships waiting operations and equipment usage would be minimum. Ship operation within the port is assimilated to a mass service waiting system in which parameters are later used to determine the main costs for ships and port equipment.

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.