6,789 research outputs found

    An improved approach for automatic process plan generation of complex borings

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    The authors are grateful for funding provided to this project by the French Ministry of Industry, Dassault Aviation, Dassault Systemes, and F. Vernadat for his review and recommendations.The research concerns automated generation of process plans using knowledge formalization and capitalization. Tools allowing designers to deal with issues and specifications of the machining domain are taken into account. The main objective of the current work is to prevent designers from designing solutions that would be expensive and difficult to machine. Among all available solutions to achieve this goal, two are distinguished: the generative approach and the analogy approach. The generative approach is more adapted to generate the machining plans of parts composed of numerous boring operations in interaction. However, generative systems have two major problems: proposed solutions are often too numerous and are only geometrically but not technologically relevant. In order to overcome these drawbacks, two new concepts of feature and three control algorithms are developed. The paper presents the two new features: the Machining Enabled Geometrical Feature (MEGF) and the Machinable Features (MbF). This development is the result of the separation of the geometrical and the technological data contained in one machining feature. The second objective of the paper is to improve the current Process Ascending Generation (PAG) system with control algorithms in order to limit the combinatorial explosion and disable the generation of unusable or not machinable solutions

    A retrospective comparative study of three data modelling techniques in anticoagulation therapy.

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    Three types of data modelling technique are applied retrospectively to individual patients’ anticoagulation therapy data to predict their future levels of anticoagulation. The results of the different models are compared and discussed relative to each other and previous similar studies. The conclusions of earlier papers are reinforced here using an extensive data set and continuously-updating neural network models are shown to predict future INR measurements best of the models presented here

    Localized Immunotherapy Delivery Using Injectable in situ Forming Chitosan Hydrogel

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    Cytokine-based cancer immunotherapies stimulate a host’s immune system to fight cancer. In particular, interleukin-12 (IL-12), a potent pro-inflammatory cytokine, has demonstrated the ability to eliminate tumors in a number of preclinical models. Toxicities associated with the systemic delivery of IL-12 have precluded its use in the clinic. We are developing a novel chitosan-based hydrogel to maintain high local concentrations of cytokines, such as IL-12, in the tumor while minimizing its systemic dissemination. This hydrogel was found to form spontaneously within ten seconds of mixing two proprietary components. To increase the usefulness of the hydrogel, an efficient mixing and delivery system is needed. We designed and evaluated a device capable of mixing two solutions from two syringes during injection. A total of eight prototypes were created using three-dimensional printers; six were printed on an Object30; one was printed on a MakerBot; another was printed on an uPrint SE Plus. Three tests were used to determine the effectiveness of the device. The first test was a dimensional test to check for fitting of the syringes and needle. After passing this test, the fluid dynamics were tested using distilled water. If the device pasted the previous tests, the third test determined the mixing ability of the device using the novel hydrogel. After success in all three tests, the sterility of the device became the main goal. Hydrogel formation was achieved but a better material for the device is still under investigation

    Seven Dimensions of Portability for Language Documentation and Description

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    The process of documenting and describing the world's languages is undergoing radical transformation with the rapid uptake of new digital technologies for capture, storage, annotation and dissemination. However, uncritical adoption of new tools and technologies is leading to resources that are difficult to reuse and which are less portable than the conventional printed resources they replace. We begin by reviewing current uses of software tools and digital technologies for language documentation and description. This sheds light on how digital language documentation and description are created and managed, leading to an analysis of seven portability problems under the following headings: content, format, discovery, access, citation, preservation and rights. After characterizing each problem we provide a series of value statements, and this provides the framework for a broad range of best practice recommendations.Comment: 8 page
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