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In the middle of a continuous and exponential development of renewable energies trend, generated by the increasing price of the conventional fuels which are quickly draining, and facing the fact that we have tremendous messages sent by our polluted Planet, the IMO (International Maritime Organization) returned its face to environment concerns in 2008. During time IMO has realized a series of environment impact studies of maritime domain and, in concordance with this idea, developed IMO's Marine Environment Protection Committee (MEPC). MEPC has given extensive consideration to control of greenhouse gas (GHG) emissions from ships which are implemented in MARPOL Annex VI as a new Chapter 4, entitled "Regulations on energy efficiency for ships". We strongly believe that there will be a rapid grow in the number of ships which will have renewable energies systems onboard in the near future. One kind of energy that can be very well applied to the naval domain is the solar energy. As the technologies are developing very fast in the domain of photovoltaics, there is a continuous need of research in order to implement the best technical solutions in naval domain, which, as we know, presents different characteristics from classic terrain applications. Thus, there are some questions that we tried to respond on this article, as: "what is the difference between efficiency of an onboard installed PV panel and a classic terrain installed PV panel?; how much will affect the albedo of the water?; how much will affect the ships' oscillation moves?; how is comporting a vertical Sun facing PV panel and a non-facing one?To respond at these questions we realized a comparative study between a simulated PV system and its similar real system installed onboard, in order to determine the differences between results and estimate how much we can take in consideration from a simulated PV classic system when we design a real onboard PV system. Index Terms-data acquisition, maritime, photovoltaic systems, power system simulation, shipbuilding industry.

No abstract

Communications applications in the underwater environment have recently developed a considerable development due to the demand for underwater research with Robot Underwater Vehicle (ROV). The most important aspects addressed by researchers are related to the speed and distance of data transmissions. In most cases, this data signal may be electromagnetic, optical or acoustic. The first two cases have limitations on the distance of the communication channel due to signal attenuation. That is why the acoustic field can be considered the favorite in this choice. In this case, the limitations of use are given by the acoustic field propagation, which depends on the temperature, salinity and pressure of the underwater environment and the result is the variation of the propagation speed. The influence of frequency on attenuation and reverberation are important factors limiting the use of the acoustic field. Based on these considerations, the paper presents an experimental transceiver model of data transmission using Frequency Shift Keying (FSK), modulation with phase discontinuity for transmitting and receiving commands at the speed of 2kbits / s

The main part of the alerting system of the GMDSS is done by automating alerting using Digital Selective Calling on VHF or MF/HF bands. Most of the small craft used to transport migrants use VHF-DSC to alert European's agencies of distress situations, which, in the all-most situations are fake. Because the maximum range of VHF propagation is around 50NM and it's related to the antennas' heights, it is necessary to increase the coverage area by installing many DSC receivers. The paper contains an example of a VHF-DSC receiver using a 20 Euros dongle and free GNU radio software. Instead to buy a maritime radio coast station the authorities can implement this system using low-cost dongle and small computers like Raspberry Pi, which also permit internet connection and IoT.