An analysis of installation of submarine pipelines

There are different methods of construction of outfall pipelines, all of them have to solve the problem of placing a tube over a known location in sea bed. This process has sometimes to be done in difficult conditions as waves, current or depths greater than 30 metres, where a diver cannot go safely beyond. Also the placement of the pipeline must be carried out without any damage to the tube, therefore a close control of the deflections and stresses in the structure must be performed. The importance of this control should be not diminished because a damage during the construction would imply a very difficult and expensive repair, that should be avoided with a proper design of the construction process. This paper is focused in the analysis of the tube during its placement according to a very well known construction method consisting in placing the tube from a boat, where all the connections between consecutive tube segments are performed, and also the whole process is controlled. This method is used for outfall as well as offshore pipelines, and it will be described in Section 2

A Survey on Intermediation Architectures for Underwater Robotics

Currently, there is a plethora of solutions regarding interconnectivity and interoperability for networked robots so that they will fulfill their purposes in a coordinated manner. In addition to that, middleware architectures are becoming increasingly popular due to the advantages that they are capable of guaranteeing (hardware abstraction, information homogenization, easy access for the applications above, etc.). However, there are still scarce contributions regarding the global state of the art in intermediation architectures for underwater robotics. As far as the area of robotics is concerned, this is a major issue that must be tackled in order to get a holistic view of the existing proposals. This challenge is addressed in this paper by studying the most compelling pieces of work for this kind of software development in the current literature. The studied works have been assessed according to their most prominent features and capabilities. Furthermore, by studying the individual pieces of work and classifying them several common weaknesses have been revealed and are highlighted. This provides a starting ground for the development of a middleware architecture for underwater robotics capable of dealing with these issues.

A Survey on Underwater Acoustic Sensor Network Routing Protocols

Underwater acoustic sensor networks (UASNs) have become more and more important in ocean exploration applications, such as ocean monitoring, pollution detection, ocean resource management, underwater device maintenance, etc. In underwater acoustic sensor networks, since the routing protocol guarantees reliable and effective data transmission from the source node to the destination node, routing protocol design is an attractive topic for researchers. There are many routing algorithms have been proposed in recent years. To present the current state of development of UASN routing protocols, we review herein the UASN routing protocol designs reported in recent years. In this paper, all the routing protocols have been classified into different groups according to their characteristics and routing algorithms, such as the non-cross-layer design routing protocol, the traditional cross-layer design routing protocol, and the intelligent algorithm based routing protocol. This is also the first paper that introduces intelligent algorithm-based UASN routing protocols. In addition, in this paper, we investigate the development trends of UASN routing protocols, which can provide researchers with clear and direct insights for further research.

Development of data reduction pipelines for GTC instruments at the UCM

The UCM Instrumentation Group (GUAIX) is developing currently Data Reduction Pipelines (DRP) for four instruments of the GTC: EMIR, FRIDA, MEGARA and MIRADAS. The purpose of the DRPs is to provide astronomers scientific quality data, removing instrumental biases, calibrating the images in physical units and providing a estimation of the associated uncertainties.

Chemical compositions of rocks and minerals from an underwater volcano of the Kuril deep-sea basin

Mineralogy and geochemistry of low-temperature hydrothermal manifestations occurring on the surface of basalts and in their cracks within a submarine volcano in the north-eastern part of the Kuril deep-sea basin have been studied. The following order of isolation of mineral phases has been found out: Fe-rich sulphides (pyrite) - Fe-rich layered silicates (hydromica of celadonite-nontronite type) - amorphous silica (opal) - Fe-oxyhydroxides (goethite) - Mn-oxyhydroxides (vernadite). Sulphide mineralization is of the phenocryst-stockwork type. Finding of pure barite fragments does not exclude presence of hydrothermal exhalations (smokers) on this volcanic structure.

Chemical composition and age of magmatic rocks from the underwater Hokkaido Rise

Geological and geophysical investigations carried out within the Hokkaido Rise showed that intrusives composing outcrops of the crystalline basement on the ocean floor form a continuous series from monzonites and diorite-monzonites to granites with prevalence of granodiorites with stable mineralogical association: biotite - hornblende - K-feldspar. Acidic volcanic rocks are characterized by a similar mineralogical association with almost complete absence of plagioclase-pyroxene species. It seems that the Hokkaido Rise, as well as the marginal oceanic Zenkevich swell as a whole are not primary oceanic structural formations and have undergone a complex and long history of geological development with intense orogenic movements that occurred in Middle Cretaceous and preceded subalkaline basalt outpouring during postorogenic subsidence of the Earth crust.

A solution for the wave velocity field existing on an underwater portion of an impervious sloping breakwater /

"Contract No. DA-22-079-civeng-63-104."

Drydock extension : a 1980 underwater technology survey for extension of time between drydockings /

"Report no. CD-D-15-81."

Meeting the submarine challenge : a short history of the Naval Underwater Systems Center /

Shipping list no.: 97-0340-P.