Notes on some small points relating to duplex balances on long submarine cables

With wind turbines increasing in size, installed at greater distances from the mainland, and greater depths, submarine cables are facing new challenges. Materials and technologies used so far for the production of submarine cables with lead, aluminium, or copper sheaths make them unsuitable or even obsolete for modern solutions such as floating wind farms. The article discusses types of submarine cables, their construction, working conditions, and operational factors, with emphasis placed on the role of the radial water barrier. The focus has been placed on dry and semi-dry designs. The article is also devoted to a discussion regarding directions of further development, possible materials, and constructions that may appear in the future. Current research and results regarding the use of multi-layer coatings with the use of thermoplastic block copolymers for the layer with high moisture absorption are also presented.

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A Thermal Model for Three-Core Armored Submarine Cables Based on Distributed Temperature Sensing

Energies ◽

10.3390/en14133897 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3897

Author(s):

Miguel Ángel González-Cagigal ◽

Juan Carlos del-Pino-López ◽

Alfonso Bachiller-Soler ◽

Pedro Cruz-Romero ◽

José Antonio Rosendo-Macías

Keyword(s):

Temperature Sensing ◽

The Finite Element Method ◽

Current Profile ◽

Distributed Temperature Sensing ◽

Numerical Resolution ◽

Electromagnetic Model ◽

Proposed Model ◽

Relative Errors ◽

Dynamic Loading Conditions ◽

Submarine Cables

This paper presents a procedure for the derivation of an equivalent thermal network-based model applied to three-core armored submarine cables. The heat losses of the different metallic cable parts are represented as a function of the corresponding temperatures and the conductor current, using a curve-fitting technique. The model was applied to two cables with different filler designs, supposed to be equipped with distributed temperature sensing (DTS) and the optical fiber location in the equivalent circuit was adjusted so that the conductor temperature could be accurately estimated using the sensor measurements. The accuracy of the proposed model was tested for both stationary and dynamic loading conditions, with the corresponding simulations carried out using a hybrid 2D-thermal/3D-electromagnetic model and the finite element method for the numerical resolution. Mean relative errors between 1 and 3% were obtained using an actual current profile. The presented procedure can be used by cable manufacturers or by utilities to properly evaluate the cable thermal situation.

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20,000 In League Under the Sea: Anonymous Communication, Trust, MLATs, and Undersea Cables

Proceedings on Privacy Enhancing Technologies ◽

10.1515/popets-2015-0002 ◽

2015 ◽

Vol 2015 (1) ◽

pp. 4-24 ◽

Cited By ~ 5

Author(s):

Aaron D. Jaggard ◽

Aaron Johnson ◽

Sarah Cortes ◽

Paul Syverson ◽

Joan Feigenbaum

Keyword(s):

Autonomous System ◽

Probability Distributions ◽

Arms Race ◽

Experimental Results ◽

Modular System ◽

Anonymous Communication ◽

Legal Assistance ◽

Correlation Attacks ◽

Submarine Cables ◽

Undersea Cables

Abstract Motivated by the effectiveness of correlation attacks against Tor, the censorship arms race, and observations of malicious relays in Tor, we propose that Tor users capture their trust in network elements using probability distributions over the sets of elements observed by network adversaries. We present a modular system that allows users to efficiently and conveniently create such distributions and use them to improve their security. To illustrate this system, we present two novel types of adversaries. First, we study a powerful, pervasive adversary that can compromise an unknown number of Autonomous System organizations, Internet Exchange Point organizations, and Tor relay families. Second, we initiate the study of how an adversary might use Mutual Legal Assistance Treaties (MLATs) to enact surveillance. As part of this, we identify submarine cables as a potential subject of trust and incorporate data about these into our MLAT analysis by using them as a proxy for adversary power. Finally, we present preliminary experimental results that show the potential for our trust framework to be used by Tor clients and services to improve security.

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