5,160 research outputs found

    The Political Economy of Industrial Policy in China: The Case of Aircraft Manufacturing

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    Since 1960, only one new country, Brazil, has succeeded in delivering more than one civil jet per month. Otherwise, all the countries now offering world-class planes were established in aviation by the end of World War I. This being said, low-cost producers within several of the newly emerging markets have already acquired front-end manufacturing expertise as a direct result of industrial offset contracts and/or other forms of technology transfer. In all such cases, government intervention, notably through state ownership, has been predominant, but failures have been numerous in view of the difficulty of aligning ownership structure to financial, managerial, and technological requirements and of garnering the support of domestic interest groups. In this paper the focus is China’s efforts to build a world-class aircraft manufacturing industry. In the first half of the 1990s the potential of the Chinese industry to mount a competitive challenge to Western aircraft builders was largely discounted. Nowadays, as China strives to bear the ARJ-21 project to execution and even considers entering the market for wide-bodies, the threat is taken more seriously. The growth in the Chinese air transport market has reinforced the bargaining power of national aircraft producers and authorities are giving priority to building science and technology capacity in this area. Progress in creating military/civilian synergies has proven much more modest – especially when compared to the shipbuilding industry – and better coordination in the overall industry comes a distant fourth in the explanations’ peaking order.http://deepblue.lib.umich.edu/bitstream/2027.42/40165/3/wp779.pd

    An ontology framework for developing platform-independent knowledge-based engineering systems in the aerospace industry

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    This paper presents the development of a novel knowledge-based engineering (KBE) framework for implementing platform-independent knowledge-enabled product design systems within the aerospace industry. The aim of the KBE framework is to strengthen the structure, reuse and portability of knowledge consumed within KBE systems in view of supporting the cost-effective and long-term preservation of knowledge within such systems. The proposed KBE framework uses an ontology-based approach for semantic knowledge management and adopts a model-driven architecture style from the software engineering discipline. Its phases are mainly (1) Capture knowledge required for KBE system; (2) Ontology model construct of KBE system; (3) Platform-independent model (PIM) technology selection and implementation and (4) Integration of PIM KBE knowledge with computer-aided design system. A rigorous methodology is employed which is comprised of five qualitative phases namely, requirement analysis for the KBE framework, identifying software and ontological engineering elements, integration of both elements, proof of concept prototype demonstrator and finally experts validation. A case study investigating four primitive three-dimensional geometry shapes is used to quantify the applicability of the KBE framework in the aerospace industry. Additionally, experts within the aerospace and software engineering sector validated the strengths/benefits and limitations of the KBE framework. The major benefits of the developed approach are in the reduction of man-hours required for developing KBE systems within the aerospace industry and the maintainability and abstraction of the knowledge required for developing KBE systems. This approach strengthens knowledge reuse and eliminates platform-specific approaches to developing KBE systems ensuring the preservation of KBE knowledge for the long term

    The Political Economy of Industrial Policy in China: The Case of Aircraft Manufacturing

    Get PDF
    Since 1960, only one new country, Brazil, has succeeded in delivering more than one civil jet per month. Otherwise, all the countries now offering world-class planes were established in aviation by the end of World War I. This being said, low-cost producers within several of the newly emerging markets have already acquired front-end manufacturing expertise as a direct result of industrial offset contracts and/or other forms of technology transfer. In all such cases, government intervention, notably through state ownership, has been predominant, but failures have been numerous in view of the difficulty of aligning ownership structure to financial, managerial, and technological requirements and of garnering the support of domestic interest groups. In this paper the focus is China’s efforts to build a world-class aircraft manufacturing industry. In the first half of the 1990s the potential of the Chinese industry to mount a competitive challenge to Western aircraft builders was largely discounted. Nowadays, as China strives to bear the ARJ-21 project to execution and even considers entering the market for wide-bodies, the threat is taken more seriously. The growth in the Chinese air transport market has reinforced the bargaining power of national aircraft producers and authorities are giving priority to building science and technology capacity in this area. Progress in creating military/civilian synergies has proven much more modest – especially when compared to the shipbuilding industry – and better coordination in the overall industry comes a distant fourth in the explanations’ peaking order.aerospace, China

    Fiscal year 1973 scientific and technical reports, articles, papers, and presentations

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    Formal NASA technical reports, papers published in technical journals, and presentations by MSFC personnel in FY73 are presented. Papers of MSFC contractors are also included

    Optimization of operation sequences using constraint programming

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    In this paper, we connect the dots: design and optimization of production systems. A possible link between these two areas, is a previously presented modeling language, Sequence Planner Language (SPL). It has been demonstrated how relevant information can be extracted from production systems modeling applications, and converted into SPL. We show how the SPL model can be converted into a constraint programming model for optimization. Also, a useful abstraction concept, work-equivalence, is introduced to enable alternative model formulations. A case study consisting of an aero engine structure assembly plant is presented, in which the efficiency of the resulting constraint programs is investigated. The formulations enabled by abstraction are shown to perform better than the standard formulation

    Structures performance, benefit, cost-study

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    New technology concepts and structural analysis development needs which could lead to improved life cycle cost for future high-bypass turbofans were studied. The NASA-GE energy efficient engine technology is used as a base to assess the concept benefits. Recommended programs are identified for attaining these generic structural and other beneficial technologies

    Saving disassembly at heavy-duty gas turbine compressor reengineering

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    In a paper the considered questions of a machine industry hard loaded responsible products resource saving at a stage of their repair, on an example of the heavy-duty gas-turbine compressors. The main causes of failure and include the results of turbo systems. The modern concept of the rational search path to the failed element of sophisticated equipment. The technique of safe disassembly of their element base in view of maintenance specificity co nditions of and residual influence on an environment is stated. Practical application of the offered approach will allow to increase quality and safety of special assignment, and introduction of the formalized technique in conditions of real manufacture will allow increase in level of efficiency and the use of available means of complex technological equipment.У статті розглянуті питання збереження ресурсу важко навантажених відповідальних виробів машинобудування на етапі їхнього ремонту, на прикладі газотурбінних компресорів великої потужності. Наведено основні причини та зазначені результати відмов турбокомпресорних установок. Розглянуто сучасні концепції пошуку раціонального шляху доступу до елемента, що відмовив, в складному встаткуванні. Запропоновано методику ощадного розбирання елементної бази газотурбінних компресорів з урахуванням специфіки умов експлуатації та залишкового впливу на навколишнє середовище
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