A method for evaluating a shallow water influence on a motor vessel driven by a drive output, including the continuous sequence of steps: determination of the water depth adjacent to the motor vessel and of a set-point speed in deep water that is expected from the predetermined drive output; calculation of the expected speed loss from the set-point speed as a function of the determined water depth; determination of the necessary output difference in the drive output that is needed in order to compensate for the expected speed loss; and display of the expected speed loss and the necessary output difference on a display unit.

The disclosure relates to a method of applying a coating to an external surface of a man-made object to be at least partly immersed in water (e.g. a vessel or an offshore drilling station) for a time period wherein there is relative movement between the immersed object and the water. The applied coating has a minimal resistance rating for a set of coatings. The method comprises a computer-implemented coating selection process, which comprises a first steps of obtaining, for each coating in the set of coatings, a total roughness value of the external surface based on a fouling roughness value, a macro roughness value and a micro roughness value associated with each coating. The coating selection process comprises in a second step selecting a coating from the set of coatings, wherein the selected coating has a minimal resistance rating associated with the obtained total roughness value for the time period. The method further comprises applying the selected coating to the external surface of the man-made object.

The disclosure relates to a method of applying a coating to an external surface of a man-made object to be at least partly immersed in water (e.g. a vessel or an offshore drilling station) for a time period wherein there is relative movement between the immersed object and the water. The applied coating has a minimal resistance rating for a set of coatings. The method comprises a computer-implemented coating selection process, which comprises a first steps of obtaining, for each coating in the set of coatings, a total roughness value of the external surface based on a fouling roughness value, a macro roughness value and a micro roughness value associated with each coating. The coating selection process comprises in a second step selecting a coating from the set of coatings, wherein the selected coating has a minimal resistance rating associated with the obtained total roughness value for the time period. The method further comprises applying the selected coating to the external surface of the man-made object.

A method for constructing a hull of an offshore structure includes (a) welding a plurality of plates together to form a plate assembly. The method also includes (b) passing the plate assembly through a rolling machine with the plate assembly in a vertical orientation. In addition, the method includes (c) bending the plate assembly into a cylinder during (b). The cylinder includes a pair of circumferentially adjacent free ends. Further, the method includes (d) welding the free ends of the cylinder together after (c) to form a cylindrical external wall.

A system for monitoring a physical change of a marine structure includes a complex optical measuring instrument configured to detect a behavior and structural change of the marine structure by using at least one optical sensor by means of optical fiber Bragg grating.

Inflatable device pressure gauge apparatus and methods are described. According to one aspect, an inflatable device pressure gauge apparatus includes a housing, an attachment mechanism configured to attach the pressure gauge apparatus to an inflatable device which comprises an air chamber which is configured to be inflated to an increased pressure above atmospheric pressure during use of the inflatable device, a pressure sensor coupled with the housing and configured to sense pressurized air from the air chamber of the inflatable device and to output a signal corresponding to an air pressure within the air chamber, a processor configured to process the signal from the pressure sensor and to control generation of a user perceptible emission regarding the air pressure of the air chamber as a result of the processing of the signal, and a power source coupled with the housing and configured to provide electrical energy to the processor.

Inflatable device pressure gauge apparatus and methods are described. According to one aspect, an inflatable device pressure gauge apparatus includes a housing, an attachment mechanism configured to attach the pressure gauge apparatus to an inflatable device which comprises an air chamber which is configured to be inflated to an increased pressure above atmospheric pressure during use of the inflatable device, a pressure sensor coupled with the housing and configured to sense pressurized air from the air chamber of the inflatable device and to output a signal corresponding to an air pressure within the air chamber, a processor configured to process the signal from the pressure sensor and to control generation of a user perceptible emission regarding the air pressure of the air chamber as a result of the processing of the signal, and a power source coupled with the housing and configured to provide electrical energy to the processor.

A catamaran lifting apparatus is disclosed for lifting objects in a marine environment. The apparatus includes first and second vessels that are spaced apart during use. A first frame spans between the vessels. A second frame spans between the vessels. The frames arc spaced apart and connected to the vessels in a configuration that spaces the vessels apart. The first frame connects to the first vessel with a universal joint and to the second vessel with a hinged connection. The second frame connects to the second vessel with a universal joint and to the first vessel with a hinged or pinned connection. Each of the frames provides a space under the frame and in between the barges that enables a package to be lifted and/or a marine vessel to be positioned in between the barges and under the frames. In this fashion, an object that has been salvaged from the seabed can be placed upon the marine vessel that is positioned in between the barges and under the frames.

A catamaran lifting apparatus is disclosed for lifting objects in a marine environment. The apparatus includes first and second vessels that are spaced apart during use. A first frame spans between the vessels. A second frame spans between the vessels. The frames arc spaced apart and connected to the vessels in a configuration that spaces the vessels apart. The first frame connects to the first vessel with a universal joint and to the second vessel with a hinged connection. The second frame connects to the second vessel with a universal joint and to the first vessel with a hinged or pinned connection. Each of the frames provides a space under the frame and in between the barges that enables a package to be lifted and/or a marine vessel to be positioned in between the barges and under the frames. In this fashion, an object that has been salvaged from the seabed can be placed upon the marine vessel that is positioned in between the barges and under the frames.

A modular housing structure comprising a plurality of modular elements each having a relative bearing structure defining an inner housing volume, and relative removable union components/devices for the reciprocal connection, associated with the bearing structure, wherein each of the modular elements comprises relative removable union components/devices for the reciprocal connection, and wherein the union components/devices are associated with the bearing structure and are of the magnetic type.