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Traffic congestion spread beyond major cities and expands on national roads that connect various sites of interest. Many of these roads pass through the towns whose inhabitants must endure the negative consequences of transit traffic: increased delays and pollution levels, decreasing pedestrians safety. Thus, it is necessary to find a balance between road users’ wishes (drivers and pedestrians) in order to reduce vehicles transit time and increased pedestrians safety. The study of road traffic is a complex problem, difficult to analyze by analytical methods and therefore it is suitable for computer simulation. Using advanced simulation software, the paper investigate the influence of traffic intensity, pedestrian crossings, traffic signals timing and traffic signals coordination parameters through microsimulation of traffic on an important national road that transit a Romanian town without bypass. The proposed solutions can lead to reduced vehicles transit time, of air pollution and an increase of pedestrians safety.

According to the transport White Paper “better modal choices will result from greater integration of the modal networks: airports, ports, railway, metro and bus stations, should increasingly be linked and transformed into multimodal connection platforms for passengers.” Transport terminals are the junction points of local, regional or inter-regional transport. The main objective of a transport terminal is to serve the passengers’ demand by maintaining their safety and comfort. Intermodal terminals have emerged as a response or solution to the demands of sustainable development (reducing congestion should be the main objective), Bucharest ranks 5th in the world at congestion (according to Tomtom Traffic Index). The use of intermodality in passenger transport significantly reduces congestion in cities. Intermodal passenger terminals lead to reduced congestion but impair passenger quality parameters such as time, comfort, convenience and even travel’s cost because each mode of transport has its own pricing principles. The problem of reducing the transit time through these intermodal terminals is the key in making the public transport more attractive; the way the terminals are designed and organized leads to their intensive use or not. The paper presents a model for designing intermodal passenger terminals that encourage modal transfer. The model’s framework suppose the correlation of the transport modes timetables, placing the platforms so that the movements between them are as small as possible, tariff integration and the use of an unique ticket, etc. The model presented within the paper has been tested on a hypothetical intermodal passenger terminal that has benefitted by transport modes schedules correlation through a linear programming with integer numbers model.

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 paper presents a method for optimizing the financing option for transport infrastructure project. The execution time for large project is substantial and the social costs generated during the construction phase are insufficient included in the assessment models. These are the main reasons for starting the research to extend the project evaluation methods with procedures that consider also social costs during the implementation of the project, besides the social costs after work completion. The proposed method aims to enhance the solution given by the current applied methods for investment assessment. Starting from the results of the present procedures of transport investment assessment, two approaches are presented. The first one assumes that the work starts at the reference year and different construction schemes can be applied. The optimal time of project implementation is determined considering the social costs during construction and after project implementation. In the second approach, the purpose is to determine the moments of the starting and the completion of the works for minimum of the losses caused by the social costs before and during the project implementation. The paper emphasizes that social cost during transport infrastructure work must be considered in investment timing. In this regard, supplementary procedures can be added to the current method used for ranking of the transport infrastructure investments. For an investment measure identified as opportune, the proposed method aim to minimize the total social cost.

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.

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.

Milling cutters belong to a widely used category of cutting tools. In this category, modular milling cutters are a narrow niche, less studied, and developed. Usually, they are symmetrical cutting tools. A milling cutting tool that can be reconfigured due to its modularity and still keeps its symmetry becomes more interesting and useful for machining. The paper presents such a new concept in a computer aided design (CAD) model of a cutting tool based on some novel features. The tool itself is designed as a modular complex. The way the torque is transmitted from the shaft to the elementary cutters is an original one, as they are joined together based on a profiled assembling. The profile is one formed of filleted circular sectors and segments. The reaming of the elementary cutters has two sections each of them assuming a task: transmitting the torque, and precisely centring, respectively. The cooling system, which is a component of the tool, provides the cutting area with coolant both on the front and side face of the cutting tool. Some nozzles placed around the cutting tool send jets or curtains of coolant towards the side surface of the cutter, instead of parallel, as some existing solutions do. The source of the coolant supply is the inner cooling system of the machine tool. This provides the tool with coolant having proper features: high enough flow and pressure. The output of the research is a CAD-based model of the modular milling cutter with a high performance cooling system. All of this model’s elements were designed taking into account the design for manufacturing principles, so it will be possible to easily manufacture this tool. Several variants of milling cutters obtained by reconfiguring the complex tool are presented. Even if the tool is usually a symmetric complex, it can process asymmetric parts. Symmetry is intensively used to add some advantages to the modular cutting tool: balanced forces in the cutting process, the possibility of controlling the direction of the axial cutting force, and a good machinability of the grooves used to assemble the main parts of the cutting tool.

It is well known the important role of the tools for mechanical processing in manufacturing within the present context of the rush for profitability and technical optimization for an environmentally friendly industrial production. Modularization of tools is a way to ensure their versatility being at the same time economically advantageous. In this paper, two milling cutters are adapted in order to be used also for surface hardening. The third tool described here is a newly designed modular tool that, according to needs, can be used to perform rough, finish milling or mechanical hardening.

Terminals constitute the factual interface between different modes and, as a result, buffer stocks are unavoidable whenever transport flows with different discontinuities meet. This is the reason why assessing materials handling and storage capacities is an important issue in the course of attempting to increase operative planning of logistic processes in terminals. Proposed paper starts with a brief review of the compatibilities between different sorts of materials and corresponding transport modes and after, a literature overview of the studies related to ports terminals and their specialization is made. As a methodology, discrete event simulation stands as a feasible technique for assessing handling and storage capacities at the terminal, taking into consideration the multi-flows interaction and the non-uniform arrivals of vessels and inland vehicles. In this context, a simulation model, that integrates the activities of an inland water terminal and describes the essential interactions between the subsystems which influence the terminal capacity, is developed. Different scenarios are simulated for diverse sorts of materials, leading to bottlenecks identification, performance indicators such as average storage occupancy rate, average dwell or transit times estimations, and their evolution is analysed in order to improve the transfer operations in the logistic process