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[en] Assessment of doctors is in a state of flux. Traditional methods of assessment have been critically examined and found inherently limited. The wholesale shift towards outcome-orientated education in the last 10 years has led to the relatively rapid development of a radically different method of assessment. This method focuses on assessing what doctors do in everyday practice rather than written or practical simulations. Known collectively as 'workplace-based assessment' tools, these have been embraced in North America, whereas they have been more cautiously adopted in the UK. However, many of these assessment tools have not been rigorously studied and, moreover, few have been specifically developed for assessing radiologists. However, they are likely to be incorporated into radiology training in the near future. This paper critically analyses both the underpinning assumptions behind this method and the evidence behind existing tools, and looks at the work that is required to develop, adopt or adapt such tools for use in radiology.
[en] Westinghouse has developed several concepts to dismantle reactor internals based on safe and reliable techniques, including Plasma Arc Cutting (PAC), Abrasive Water Jet Cutting (AWJC), Metal Disintegration Machining (MDM), or mechanical cutting. Westinghouse has applied its technology to all types of reactors covering Pressurized Water Reactors (PWR), Boiling Water Reactors (BWR), Gas Cooled Reactors (GCR) and sodium reactors. The primary challenges of a segmentation and packaging project are to separate the highly activated materials from the less-activated materials and package them into appropriate containers for disposal. Since space is almost always a limiting factor it is therefore important to plan and optimize the available room in the segmentation areas. The choice of the optimum cutting technology is important for a successful project implementation and depends on some specific constraints like disposal costs, project schedule, available areas or safety. Detailed 3-D modeling is the basis for tooling design and provides invaluable support in determining the optimum strategy for component cutting and disposal in waste containers, taking account of the radiological and packaging constraints. Westinghouse has also developed a variety of special handling tools, support fixtures, service bridges, water filtration systems, video-monitoring systems and customized rigging, all of which are required for a successful reactor vessel internals segmentation and packaging project. The purpose of this paper is to provide an overview of the Westinghouse reactor internals segmentation experience by illustrating projects related to various types of reactors and providing feedback from project execution. (authors)
[en] Attention focuses on means of improving the efficiency and capabilities of multipurpose machine tools by expanding the range of available tools and the methods of surface machining. As an example, new approaches are applied to the manufacture of complex parts by means of a multipurpose machine tool. The machining efficiency is improved.
[en] This paper addresses the problem of generating optimal inspection strategies for randomly failing equipment where imminent failure is not obvious and can only be detected through inspection. Inspections are carried out following a condition-based procedure. The equipment is replaced if it has failed or if it shows imminent signs of failure. The latter state is indicated by measuring certain predetermined control parameters during inspection. Costs are associated with inspection, idle time and preventive or corrective actions. An optimal inspection strategy is defined as the inspection sequence minimizing the expected total cost per time unit over an infinite span. A mathematical model and a numerical algorithm are developed to generate an optimal inspection sequence. As a practical example, the model is applied to provide a machine tool operator with a time sequence for inspecting the cutting tool. The tool life time distribution and the trend of one control parameter defining its actual condition are supposed to be known
[en] The application of CNC machine tool being widely expanded according to variety of machine work method and rapid promotion of machine tool, cutting tool, for high speed efficient machine work. In order to conduct of the project of manufacture and maintenance of laboratory equipment, production design and machine work technology are continually developed, especially the application of CNC machine tool is very important for the improvement of productivity, quality and clearing up a manpower shortage. We publish technical report which it includes CNC machine tool program and drawing, it contributes to the systematic development of CNC program design and machine work technology
[en] The requirements of contemporary industry and the flashing development of modern sciences impose restrictions on the majority of the elements of machines; the resulting financial constraints can be satisfied by a better output of the production equipment. As for those concerning the design, the resistance and the correct operation of the product, these require the development of increasingly precise parts, therefore the use of increasingly powerful tools . The precision of machining and the output of the machine tools are generally determined by the precision of rotation of the spindle, indeed, more this one is large more the dimensions to obtain are in the zone of tolerance and the defects of shape are minimized. During the development of the machine tool, the spindle which by definition is a rotating shaft receiving and transmitting to the work piece or the cutting tool the rotational movement, must be designed according to certain optimal parameters to be able to ensure the precision required. This study will be devoted to the choice of the material of the spindle fulfilling the imposed requirements of precision.