Dolphins are essential structures used in gas and oil terminals for berthing and mooring purposes. In essence, design of these structures is mostly based on linear analysis, so that the effect of nonlinearity on the actual responses is not considered. In this paper, the effect of nonlinearity caused by the gap modeling between parts of the structure is investigated and the modeling is carried out using accurate and efficient finite element software. As a case study, a mooring dolphin located in the Persian Gulf is simulated in order to demonstrate the nonlinear analysis effects. In contrary to the most common mooring dolphins, the dolphin is designed to have flexible structural behavior. As a result, it is comprised of three short piles connected by a triangle-shape box girder from the top. The box girder is composed of two triangle plates as flanges, which are connected by means of vertical stiffeners acting as web. Besides, three torsion bars are used to change the direct shear to a torsion shear to get a more efficient force transmission. In the piles-box girder connection, where piles pass through the holes prepared in the flanges, there is a considerable difference between the diameter of piles and holes as a tolerance (gap) for construction and codes provisions (BS 6349). The nonlinear effects are mainly caused by the gap in this connection besides the vertical supports of the box girder and the torsion bars. This paper contains the results of a nonlinear static analysis in which the gap between different parts is modeled using nonlinear spring elements to reach a convergence in solving the equations. Results are then compared with the linear static analysis of a similar dolphin, which gaps are not modeled in it and nonlinear effects are presented.

Background: Complex regional pain syndrome (CRPS) is a common complication in orthopedic surgeries. The present study aimed at evaluating the effect of calcitonin in the treatment of patients with CRPS.

This paper contains the results of mooring analyses of two side-by-side operating crane barges in the installation procedure of a jacket type platform in an oil-gas field in the Persian Gulf. Since the vessels are proposed to operate next to a fixed structure, making sure about their displacements and a convenient clearance between them and the jacket is a highly important aspect of the design process. In essence, the analyses consist of setting an appropriate configuration and positioning of the vessels relative to each other, considering a reasonable gap between vessels and the jacket, connecting the vessels together, and studding the behavior of the moored system when it is subjected to a set of environments. In particular, an equilibrium configuration is found when the system is subjected to the mean force of the environment which consists of waves, wind gusts and currents. Then the dynamics of the system about the mean position is investigated. In order to study the influence of a dynamic mooring analysis, two cases are compared; one considering weight and buoyancy as the only forces acting on the lines and carrying out a quasi-static mooring analysis, and the other taking into account the hydrodynamic forces from the mooring lines. An accurate and efficient finite element program for the coupled analysis of the hull-mooring system is used and two types of modeling the connected vessels are compared; one using joints with restraints for all relative motions but in relative roll, and the other using slings and fenders. In all cases, the results of time domain analyses consisting of mooring line loads and motion responses of the vessels are presented in time histories and the statistics are studied.

Introduction : Avascular necrosis (AVN) is a rather common complication of scaphoid fractures, particularly scaphoid waist nonunion, which may occur even after surgical fixation. In the present investigation we aimed to evaluate the efficacy of Mathoulin technique in the surgical fixation of scaphoid waist nonunion with definite proximal AVN. Methods A total of 35 cases of scaphoid waist non-union with definite proximal AVN undergoing surgical fixation in a major tertiary referral orthopaedic hospital in northwestern Iran in 2021 were enrolled. Postoperative pain intensity, grip strength (based on modified mayo wrist score) and carpal range of motion (angles of movements) were evaluated at four time intervals, 1, 4.5, 6 and 9 months following Mathoulin surgical fixation. Results A total of 35 patients, 28 (80%) male and 7 (20%) female, with a mean age of 28.96 ± 1.89 were investigated. By the end of the 9th month, no patients complained of severe pain, and 33 (94.28%) participants only reported mild pain. Carpal flexion, extension, supination and pronation angles significantly improved following surgery. Grip strength in 29 patients improved significantly. Wrist function Union as achieved in 33 (97.29%) patients. Conclusion Mathoulin method in patients with proximal definite AVN with Scafoid Waist fusion leads to a reduction in pain intensity, improvement of motor angles, grip strength and satisfaction with surgery to a desirable extent.