Volume 39 (2016): Edizione 1 (October 2016)

The work describes the impact the reliability of the information quality IQ for information and communication systems. One of the components of IQ is the reliability properties such as relativity, accuracy, timeliness, completeness, consistency, adequacy, accessibility, credibility, congruence. Each of these components of IQ is independent and to properly estimate the value of IQ, use one of the methods of modeling uncertainty. In this article, we used a hybrid method that has been developed jointly by one of the authors. This method is based on the mathematical theory of evidence know as Dempstera-Shafera (DS) theory and serial links of dependent hybrid named IQ (hyb).

The military networks, contrary to commercial ones, require standards which provide the highest level of security and reliability. The process to assuring redundancy of the main connections through applying various protocols and transmission media causes problem with time needed to re-establish virtual tunnels between different locations in case of damaged link. This article compares reliability of different IP (Internet Protocol) tunnels, which were implemented on military network devices.

The article presents a model of Bring Your Own Device (BYOD) as a model network, which provides the user reliable access to network resources. BYOD is a model dynamically developing, which can be applied in many areas. Research network has been launched in order to carry out the test, in which as a service of BYOD model Work Folders service was used. This service allows the user to synchronize files between the device and the server. An access to the network is completed through the wireless communication by the 802.11n standard. Obtained results are shown and analyzed in this article.

The article refers to the impact of damage and dynamic variables on operation of routing protocols and consequently to the whole network (Technical Object - TO) determining its reliability and effectiveness. On this purpose, there was introduced the characteristic of the routing protocols and both an internal and an exterior gateway. Then, it was built the network architecture based on the TCP/IP stack. In the stack, there were created three autonomous systems and one of them was the backbone of the network. What is more, reliability tests, which have been performed, consisted of a resistance to physical damage to the network and dynamically changing parameters of the network as well as performance test.

This article introduces division of transport systems into land transport systems (road and rail) as well as land and water transport systems (inland and sea), depending on the type of environment in which these systems carry out their tasks. Such systems comprise the class of social engineering systems of the Man – Technological Object – Environment (M – TO – E) type. Such systems are influenced by forcing factors, leading to changes in their condition. Such factors may be divided into operational, external and anthropotechnical and they cause the degradation of the system on various levels, including a decrease of the degree of its safety. The article attempts to evaluate the safety of the operation of transport systems on the basis of the evaluation of the safety of the transport process carried out over a defined time interval Δt. The evaluation of the safety of the implemented transport process was prepared on the basis of a set of calculated index values determined depending on the type of transport.

This article characterizes circumstances associated with the formation of sediment in FAME and factors intensifying this process. It describes the formation of sediment due to oxidation of FAME and the precipitation of sediment in low temperatures of storage which relates to the raw material nature and incomplete production process of FAME. It indicates more causes of sediment’s formation originating from the incompatibility of construction materials used in logistics and microbiological contamination.

The paper presents feature of geometric track irregularities occurring on tram infrastructure with varying levels of maintenance and their influence on vehicle’s dynamic response. Measurements of vehicle’s model masses accelerations were conducted during rides on chosen track sections projecting real geometry. Frequency characteristics of vibration accelerations obtained from simulation and spectra of measured track irregularities were shown and compared to find the relationship between them.

The article presents results of tribological research carried on four ball tester and dynamic rheometer for different magnetorheological fluids. The wear test was conducted with and without magnetic field. The dynamic rheology measurement was done at wide range of velocity. The inteligent fluids differed from each other by an amount of solid phase and kind of base liquid.

The method of risk assessment based on ship systems technical failures during the passage in the region of Świnoujście of the large LPG (liquefied petroleum gas) tanker is presented. The statistical reliability indicators and the simulation model of ships manoeuvring. The researches carried out within this paper let to determine the safety level and necessary tug escort service during the passage of the ship with the hazardous cargo in the port area.