We reviewed 13 cases of osteochondritis dissecans of the patella followed-up for 18 months to 19 years. Two were treated conservatively with excellent results, and 11 by operation with six excellent, four good and one fair result. There was complete radiographic healing of the defect in 10 cases and partial healing in three. The size of the osteochondritic lesion appeared to be of prognostic si...

Industries have many rotational operations that are used for design, transport, lift, drilling, rolling, robotics, and other applications. These rotating applications require a proper controller accurate control of the operation. Separately excited DC motors (SEDCMs) versatile various industrial because their specific speed characteristics. So, smooth operation an SEDC motor, controllers should...

Purpose. Development of a methodology for optimizing the technological parameters airlift operation, based on analysis pressure balance in annulus and drill string that occurs during drilling. Methodology. The tasks were solved by complex research method, which includes review generalization literary patent sources, analytical studies existing methods drilling with reverse circulation using an ...

This paper presents ongoing research in improvement of analytical tools for the characterization of rock mass structure from oriented borehole discontinuity data. Using automated multivariate cluster analysis and the “three dimensional stereonet” provides for fast and objective characterization of oriented core discontinuity data. Improvements to the CYL software include three new methods of cl...

Shahid Technique’ to help reduce suitable fracture configurations to facilitate ease of the Lag Screw Principle. In oblique fracture configurations, inter fragmentary compression at a fracture site can be achieved using the ‘Lag Screw Principle’. A screw inclination perpendicular to the fracture plane in this configuration allows for optimal compression. If compression is applied at an angle gr...

K e y w o r d s F o u r t h g r a d e fluid, Unsteady flow, Lie symmetries. 1. I N T R O D U C T I O N In recent years, considerable efforts have been usefully devoted to the s tudy of flow of nonNewton ian fluids. This is ma in ly due to their m a n y appl icat ions in pe t ro leum drilling, manufactu r ing of food and paper, and other similar activities. A vast a m o u n t of l i te ra ture i...

This paper examines the diverse nature of user reactions to information technology (IT) within the social-historical context of its organizational use. Employing activity theory as a conceptual framework, we conduct an interpretive analysis of physicians work, perceptions, and IT usage experience at a large community hospital to understand why some of these physicians were favorably disposed to...

Control of well drilling operations poses a challenging issue to be tackled. The loss of well control could lead to the occurrence of blowout as a severe threat, involving the risk of human lives and environmental and economic consequences. Conventional proportional-integral (PI) controller is a common practice in the well control operation. The small existing margin between pore pressure and f...

The distinguishing characteristics of carbon fibre reinforced laminates, like low weight, high strength or stiffness, had resulted in an increase of their use during the last decades. Although parts are normally produced to “near-net” shape, machining operations like drilling are still needed. In result of composites non-homogeneity, this operation can lead to delamination, considered the most ...