Parry-Romberg syndrome (PRS) is an uncommon degenerative condition characterized by a slow, progressive, and, generally, unilateral atrophy of facial tissues, including muscles, bones and skin. Ophthalmological and neurological manifestations have frequently been observed and few oral changes have been reported. This article reports a case of PRS in a 22-year-old woman, exhibiting facial asymmetry, hypoplasia of the right side of the face, areas of skin hyperpigmentation, and oral alterations, involving the mandible and teeth. These clinical and radiological findings led to the diagnosis of PRS. In an attempt to improve the patient's facial aesthetic and the dental functions, oral pentoxifylline, orthodontic rehabilitation, and subcutaneous injections of polymethylmethacrylate microspheres were used as part of the treatment for the facial atrophy. Together, these approaches accounted for a minimal invasive treatment with long term satisfactory results.
The installation of a subsea equipment such as manifold needs careful planning and coordination. Studies on the behavior of the dynamic responses are crucial to guarantee safety. Some important factors in these operations include the current profile, waves characteristics, winches motions at topside, and the elastic behavior of the cable (due to resonance effects). Currently, most of the available commercial codes use simplified models for the hydrodynamic forces of submerged equipment. However, for cases with complex geometries and strong interactions with the environmental loads, those models fail to represent correctly the dynamics. In this paper we present an initial method and a hydrodynamic model to include terms that allow the modelling of complex behavior of submerged complex geometries by using hydrodynamic derivatives extracted from model tests. To verify the procedure, tests were performed both at a flume tank and at a towing tank. The model was implemented in a commercial code by using a Simplified Buoy model, to which a python procedure that calculated the hydrodynamic forces was attached. The study was divided into two phases: the first one consisted of the verification of the effectiveness of the external routine. This was done for a manifold in 1DOF and then in 6 DOF. In the second phase, the dynamic maneuvering model using Hydrodynamic Derivatives was implemented as an external routine and, using the output from dynamic excitation experiments at small scale with a manifold, kinematical behavior results were compared. Results showed good adherence, although some further investigations are still needed.
During the installation of a subsea module it is extremely important to guarantee that the structure will not be damaged, as this would imply in elevated costs and hazards to the environment. In order to minimize these risks, the installation process can be simulated inside software that use numerical modeling by considering different environmental conditions, so that a safer procedure with more adequate operational window can be achieved. However, these software can be very expensive, and this kind of simulations usually takes a long time, making it very convenient when one has access to a simplified model, capable of simulating different conditions in a short period of time, while still providing reliable results. This paper presents a simplified model developed in Python programming language, which uses a fourth-order Runge-Kutta method to solve the equation of motions that governs a vertical installation process. The installation ship's motions were applied to the top of the cable, simulating its connection to a crane aboard, and then the motions of the suspended equipment and the cable tension could be calculated. The results obtained through the use of this simplified model were then compared to the ones obtained through the use of a much more complex model using the OrcaFlex® software and to experimental data.
Due to risks involved during the installation of subsea equipment, it is necessary to simulate the installation process to determine a safe operating window. However, most of the software capable of running these kinds of simulations are very expensive, and these simulations usually take a long time to be made. It is then very convenient to develop a simplified model, capable of running these analyses in a short period of time while still providing us with reliable results. This model was developed using the Python programming language, where a fourth-order Runge Kutta method was implemented to solve the equation of motions that governs the manifold’s installation process. The assumptions are that the wave forces are applied to the ship executing the manifold installation. The ship’s motions were applied at the top of the cable, connected to the crane, so the manifold motions underwater and the cable tension could be calculated. Previously, a simplified one-degree of freedom (1DoF) model was developed and compared to other numerical models and experimental data. In this present work, the model was then expanded to motions in a vertical plane, that is, three degrees of freedom (3 DoF), in order to better represent the physics of the real problem. Its results were then compared to the ones obtained by the 1 DoF model and to the experimental results. The 3 DoF model resulted in a dynamic response closer to the ones observed in the experiments, which shows that it is a better representation of the problem.
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