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A motor assembly may comprise a motor assembly and a crankshaft. The motor assembly may include a... more A motor assembly may comprise a motor assembly and a crankshaft. The motor assembly may include an engine block defining a first cylinder bank defining two cylinders and a second bank defining two cylinders, wherein a V4-assembly is formed. The crankshaft may comprise a first connecting rod pin, a second connecting rod pin, a third crankpin, and a fourth connecting rod journals. The fourth connecting-rod pin may be rotationally offset from the first rod pin technically to a first angle of less than two hundred and seventy degrees in the direction of rotation of the crankshaft. The second and third connecting-rod pin can be rotationally technically disposed between the first connecting-rod pin and the fourth connecting-rod pin in the direction of rotation.
Revision total hip arthroplasty often presents surgeons with difficult bone loss problems. The pu... more Revision total hip arthroplasty often presents surgeons with difficult bone loss problems. The purpose of this study was to evaluate the results of hip revision surgery according to bone stock We evaluated, in a retrospective study, 148 hip revision surgeries during 2004 to 2010. The Harris Hip Score (HHS), the acetabular cementation, the AAOS classification, the SOFCOT 99 bone loss grading and Barrack classification were used for clinical and radiological assessment. It can be observed significant improvement of HHS from a mean value of 45 preoperatively to 77.2 points postoperatively. Grade B acetabular cementation was observed in a significantly higher rate for situations that needed acetabular allograft reconstruction and where it cannot be performed because of allografts lack. Barrack grades C and D cementation were associated with 70% of SOFCOT 99 stage III and IV cases and only 5% of SOFCOT 99 stage 0-II cases.Using bone graft seems to be a reliable solution for restoring bon...
Hydroforming is a process used to manufacture tubular sections from circular tubes. Two systems f... more Hydroforming is a process used to manufacture tubular sections from circular tubes. Two systems for hydroforming are mainly used, high pressure hydroforming (HPH), and pressure sequence hydroforming (PSH). In this paper, an energy approach is used to calculate the compressive forces developed in the tube wall during deformation in PSH. The pressure required to prevent buckling of the tube wall is estimated based on a two dimensional buckling model. The differences in the mechanics of deformations between HPH and PSH are explained. The advantages and limitations of both systems are also summarized.
Journal of Materials Processing Technology, 2007
A motor assembly may comprise a motor assembly and a crankshaft. The motor assembly may include a... more A motor assembly may comprise a motor assembly and a crankshaft. The motor assembly may include an engine block defining a first cylinder bank defining two cylinders and a second bank defining two cylinders, wherein a V4-assembly is formed. The crankshaft may comprise a first connecting rod pin, a second connecting rod pin, a third crankpin, and a fourth connecting rod journals. The fourth connecting-rod pin may be rotationally offset from the first rod pin technically to a first angle of less than two hundred and seventy degrees in the direction of rotation of the crankshaft. The second and third connecting-rod pin can be rotationally technically disposed between the first connecting-rod pin and the fourth connecting-rod pin in the direction of rotation.
Revision total hip arthroplasty often presents surgeons with difficult bone loss problems. The pu... more Revision total hip arthroplasty often presents surgeons with difficult bone loss problems. The purpose of this study was to evaluate the results of hip revision surgery according to bone stock We evaluated, in a retrospective study, 148 hip revision surgeries during 2004 to 2010. The Harris Hip Score (HHS), the acetabular cementation, the AAOS classification, the SOFCOT 99 bone loss grading and Barrack classification were used for clinical and radiological assessment. It can be observed significant improvement of HHS from a mean value of 45 preoperatively to 77.2 points postoperatively. Grade B acetabular cementation was observed in a significantly higher rate for situations that needed acetabular allograft reconstruction and where it cannot be performed because of allografts lack. Barrack grades C and D cementation were associated with 70% of SOFCOT 99 stage III and IV cases and only 5% of SOFCOT 99 stage 0-II cases.Using bone graft seems to be a reliable solution for restoring bon...
Hydroforming is a process used to manufacture tubular sections from circular tubes. Two systems f... more Hydroforming is a process used to manufacture tubular sections from circular tubes. Two systems for hydroforming are mainly used, high pressure hydroforming (HPH), and pressure sequence hydroforming (PSH). In this paper, an energy approach is used to calculate the compressive forces developed in the tube wall during deformation in PSH. The pressure required to prevent buckling of the tube wall is estimated based on a two dimensional buckling model. The differences in the mechanics of deformations between HPH and PSH are explained. The advantages and limitations of both systems are also summarized.
Journal of Materials Processing Technology, 2007