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Abstract

This paper presents the results of analyses of the series resonance phenomenon in a system containing supercapacitors. The specific features of such components, especially the diffusion processes, cause their dynamic properties significantly differ from those of typical capacitors. In contrast to other authors work, the presented results were obtained during discharging of super-capacitors through periodically changing resistor. Such procedure corresponds to conditions when supercapacitors can be discharged by periodically changing loads. Analysis of resonance phenomena is a very important task; especially in power supply circuits, where supercapacitors often act as energy storage elements. The tests carried out for selected supercapacitors and frequencies range were verified practically using a specially prepared test system.

Abstract

Monitoring of country maritime border is an important task of the Border Guard. This activity can be enhanced with the use of the technology enabling gathering information from distributed sources, processing of that information and its visualization. The paper presents the next stage of development of the STRADAR project (Streaming of real-time data transmission in distributed dispatching and teleinformation systems of the Border Guard), which is realized for the security and defence of the country. In the paper, storing, processing and visualization of the radar data, which is one of the tasks of the discussed scientific and research project, is described. Firstly, the general principle of radar data flow in the system was presented. Secondly, technical software description was described. Finally, radar data visualization functionality was presented.

Abstract

The aim of the article is to show the changes taking place in the structures of logistical support of the Polish Navy, focusing on the changes in the way of supplying ships of the Polish Navy. In recent years, the Polish Navy has undergone many changes in the subject matter, starting from the liquidation of the Logistics of the Polish Navy and the Polish Navy Command, including the Management of Logistics Planning. The changes contributed to the centralization of Logistics, creating the Inspectorate for Armed Forces Support of the Republic of Poland, which focused on the main burden of tasks related to, among others, repairs, modernization and supply of ships. On the other hand, it extends the time of issuing opinions on, for example, the protocols for assessing the technical condition of military equipment (ME), which are the basis for the replacement, repair or further exploitation of the ME.

Abstract

In the paper, there has been determined an exponential element in the discrete model of the non-classical Bittner operational calculus for the n th-order forward difference.

Abstract

The paper presents a formal and legal status within the scope of design, construction and equipping the Polish Navy ships. Regulations in force in the Ministry of National Defence are not complete and have a significant impact on the possibilities and limited efficiency of building new ships.

The article presents an attempt to systematise issues in terms of the construction of new ships for the Polish Navy. Fundamental attention was focused on identification of existing gaps in the regulations, as well as presenting proposals to eliminate them.

Abstract

The paper attempts to analyze the technical possibilities of using a compressor heat pump to recover waste heat from energy processes implemented by a watercraft. The amount of waste heat that could be used for the heating needs of the vessel was estimated and the hydrothermal potential of the marine waters was assessed. The possibilities of reducing the power of the ship's power plant used to power the ship's heating installation were determined.

Abstract

Detecting and recognizing text in natural scenes (e.g. streets, restaurants, shops, etc.) could be a part of an artificial intelligence system, especially with regard to the speech synthesis system. Properly detected text is passed to a recognition stage and then to the speech synthesis system, which translates text to speech. Research is carried out for the ‘Toucan Eye’ project — embedded device with artificial intelligence system able to help people with impaired sight. Due to constrained resources and abilities of embedded devices, criteria for text spotting must be met. First criterion is quality of detected and recognized regions with text and the second is time spent on both operations. Particular stages of the system and chosen methods of text spotting under aforementioned constraints are presented.

Abstract

It is very common for users to create weak passwords. Currently, the majority of websites deploy password strength meters to provide timely feedback. These meters are in wide use and their effects on the security of passwords have been relatively well studied. In this paper another type of feedback is studied: a gamified approach supported by fear appeal. In this approach, users are encouraged to make passwords stronger through the use of visual and textual stories. This approach is supported by data-driven suggestions about how to improve password security as well as by fear appeal. To prove the effectiveness of this gamified password creation process, an experiment was performed in which users changed their passwords in two ways: without any feed-back, and with gamified feedback with fear appeal. To support the initial findings a questionnaire was completed by participants at the end of research.

Abstract

The article discussed aim to introduce readers to the problem matter in connection with the changes taking place within the area related to the issue of metrology in the Armed Forces of the Polish Republic. The article depicts the current situation along with the changes, which took place over the recent years, in the structures of Military Metrology, and it presents the major directions of its development, with particular emphasis on the automation of the calibration process.

Abstract

In this paper a results of a transient analysis of the linear actuator is presented. The linear actuator consist of the three cylindrical unmovable coils surrounded by a soft ferromagnetic case, a runner made from sequence of ferromagnetic and permanent magnet rings. The model of the linear actuator was implemented into two software: the Comsol Multiphysics and the Matlab-Simulink. Both environments are commonly used in simulation analysis, but the first one uses Finite Element Method (FEM) and the second one uses Ordinary Differential Equations (ODE). Moreover, the dynamic model was analysed in Matlab-Simulink software with value of electromagnetic phenomena implemented from Comsol Multiphysics. Comparison was made due to the time needed for calculation, accuracy of the simulation model as well as the as utility for further optimization process.