http://hdl.handle.net/10453/11590 Thu, 23 May 2013 15:53:14 GMT 2013-05-23T15:53:14Z http://hdl.handle.net/10453/19435 Control of Non-linear vibrations using three-to-one internal resonances Ji Jinchen; Zhang Nong S.S. Law, L. Cheng, Y. Xia, and Z.Q. Su A weakly nonlinear vibration absorber is used to suppress the primary resonance vibrations of a single-degree-of-freedom weakly nonlinear oscillator subjected to periodic excitation. The linearized natural frequency (low frequency mode) of the nonlinear absorber is tuned to be approximately one-third of the linearized natural frequency (high frequency mode) of the primary nonlinear oscillator. The cubically nonlinear coupling of stiffness establishes the terms that develop three-to-one internal resonances. The low frequency mode required for the absorber can be achieved by a light-weight mass nonlinear attachment with small values of linear and nonlinear stiffness of coupling. The method of multiple scales is used to obtain the averaged equations that determine the amplitudes and phases of the first-order approximate solutions. Numerical results are given to show the effectiveness of the nonlinear absorber for suppressing nonlinear vibrations of the primary nonlinear oscillator under primary resonance conditions. Sat, 01 Jan 2011 00:00:00 GMT http://hdl.handle.net/10453/19435 2011-01-01T00:00:00Z http://hdl.handle.net/10453/19434 Surgical Adhesion and Its Prevention Godara Pankaj; Milthorpe Bruce P. Ducheyne, K.E. Healy, D.W. Hutmacher, D.W. Grainger, C.J. Kirkpatrick Adhesion of freely moving tissues and organs due to surgical injury and trauma can be a serious postoperative complication. High rates of incidence due to surgical intervention, especially associated with abdominal procedures, have been reported. This chapter gives an introduction to the formation of adhesions, with particular focus on peritoneum, urinary and reproductive (female) systems, tendon, ligament, joint, and pericardium. A number of techniques, treatments, and materials have been proposed for the prevention/reduction of adhesion formation. Of these, barrier methods are considered the only effective method currently available. An overview of biomaterials currently used as barriers for postsurgical tissue adhesion is presented. Current clinical practice utilizes solid membranes/mechanical barriers, spray-on, and gel and liquid barriers. These barriers can be either resorbable, nonresorbable, or a combination of both. Complications of barrier films are examined, and design criteria for barrier membranes are presented. Adhesion formation can be beneficial in particular circumstances, such as for anchoring implants, and these uses are commented upon. Much advancement has been made in this area, thanks to the increasing knowledge and understanding regarding the events that control adhesion formation, but there is still a long way to go before an optimum solution to this problem is found. Sat, 01 Jan 2011 00:00:00 GMT http://hdl.handle.net/10453/19434 2011-01-01T00:00:00Z http://hdl.handle.net/10453/17634 Guide to Demand Management Turner Andrea; Willetts Juliet; Fane Simon; Giurco Damien; Kazaglis Alexander; White Stuart Tue, 01 Jan 2008 00:00:00 GMT http://hdl.handle.net/10453/17634 2008-01-01T00:00:00Z http://hdl.handle.net/10453/16745 On necessary and sufficient conditions for H-Infinity output feedback control of Markov jump linear systems Li Li; Ugrinovskii Valery NA This note addresses the output feedback H8 control problem for continuous-time Markov jump linear systems. It is shown that the feasibility of a set of linear matrix inequalities is both sufficient and necessary for the existence of a solution. Under standard assumptions, we also give a Riccati-type sufficient and necessary condition for an H8-suboptimal controller to exist Sun, 01 Jan 2006 00:00:00 GMT http://hdl.handle.net/10453/16745 2006-01-01T00:00:00Z