查看更多>>摘要：Aluminium is being increasingly used in all fields of industry. Especially if it is about the structures like car bodies or frames for transportation units aluminium replaces steel. The components used are regularly assembled by joining welds. Therefore there is an increasing need for reliable repair work on aluminium welds. Repair work to aluminium structures is conducted extremely successfully. This paper will present considerations associated with the repair of aluminium structures due to practical examples. A focus will be the investigation of finding reasons for appearance of failures. Repair strategies are developed to help to prevent problems associated with repair work and to help ensure consistently successful repairs.
查看更多>>摘要：A mathematical model for translating machine settings from universal Cradle-Type hypoid generator to Cartesian-Type hypoid generator is proposed in this paper. A mathematical model of universal Cradle-Type hypoid generator was proposed by Fong [12] to simulate conventional hypoid generators including face milling and face hobbing machines. A few years ago, the Gleason Works presented the Phoenix hypoid generator, which is a Cartesian-Type machine, and the machine is gaining good commercial success. Therefore, we proposed a mathematical transformation model to translate the machine settings from conventional Cradle-Type hypoid generator to the new Cartesian-Type CNC machine. The proposed mathematical equations can be used to implement the existing cutting method on the six-axis CNC machine.
查看更多>>摘要：The key element of the in-process surface roughness monitoring system is the decision-making model, which is utilized to analyze the input factors and then to generate a proper output. The success of the in-process monitoring system depends on the accuracy of the decision-making model. To increase the accuracy and reliability of model, it is important to reduce the variation of the inputs. To achieve this objective, an integration of regression and neural network was developed as a decision-making model in this research. In this integrated model, the regression model was applied as a filter to sort the input variables into groups. Furthermore, the grouped data was implemented to train and to generate different neural networks models to reduce the affection of input variation and increase the accuracy of the monitoring system. The input variables was first filtered by the threshold of regression model, and then analyzed by different neural networks model based on the filtered result. Finally, to evaluate the performance of the integrated model, the regression neural network and traditional neural networks were both developed for surface roughness monitoring system in an end milling operation to compare the accuracy of systems.
查看更多>>摘要：Increasing the productivity and the quality of the machined parts are the main challenges of manufacturing industry, in particular for difficult-to-machine materials, such as Inconel 718, employed in aeronautic and aerospace applications. A L_(18) (2×3~7) orthogonal array (OA) and signal-to-noise (S/N) were employed to analyze the effect of mill parameters when milling Inconel 718. Experimental results indicated that the cutting tool, depth of cut, cutting speed, feed rate, frequency and coolant have statistical and physical significance on the flank wear, surface roughness and cutting force obtained, respectively.
查看更多>>摘要：There is an increasing need in modern cities for automated Crowd Condition Monitoring (CCM) in order to provide continuous real-time on-line information regarding the density, number and movement behaviour of crowd within a specific area in order to allow the required level of services and facilities to be specified and directed. This paper describes the novel application of low-cost infrared system for estimating people's density using infrared thermography. Sensor fusion system is developed to compensate for environmental noise. The results show that the suggested monitoring system could provide an efficient method to estimate crowd's density.
查看更多>>摘要：Condition monitoring systems of manufacturing processes have been recognised in recent years as one of the key technologies that provide the competitive advantage in many manufacturing environments. It is capable of providing an essential means to reduce cost, increase productivity, improve quality and prevent damage to the machine or work-piece. Turning operations are considered one of the most common manufacturing processes in industry. Despite recent development and intensive engineering research, the development of tool wear monitoring systems in turning is still on-going challenge. In this paper, force and acoustic emission signals are used for monitoring tool wear in a feature fusion model. The results prove that the developed system can be used to enhance the design of condition monitoring systems for turning operations to predict tool wear or damage.
查看更多>>摘要：Based on GT-POWER software, simulation model of working process of a long-stroke sequential turbocharging (STC) diesel engine is set up, the calculated result tends to be in agreement with the experimental ones. It proves that the calculation model,method and the selection of the relative parameters are reasonable and the model could predict and improve the performance of the diesel well. To avoid the surging problem and extend its working area, performance parameters of diesel which uses STC with bypass are calculated and compared with experimental data. The paper mainly analyzes the performance and running process of diesel.Finally, the switch point and bypass area of STC are confirmed.
查看更多>>摘要：The surface micro-topography characteristics of micro-WEDM, which can have a directly significant impact on the parts usability properties, have been attached more and more importance by people. In this study, the method of statistical analysis is applied to work out the two-dimensional autocorrelation function figure and the power spectrum density function figure of the surface micro-topography of micro-WEDM. It can be seen that there are more sharp and narrow peaks and high frequency components, meanwhile, there are some low frequency wave components on the surface. A conclusion is arrived at that the three-dimensional (3D) surface micro-topography of micro-WEDM shows isotropy through analyzing its texture characteristics. The results can provide the theoretical basis for further establishing the appropriate evaluation parameters for the surface roughness of micro-WEDM.
查看更多>>摘要：War-broken parts could be repaired quickly without power and gas in the field by using the thermit welding technology. In this paper, experimental and structural analysis on strength of thermit welding was made. According to orthogonal experiments, the pressure mode was found to influence tensile stress most, then the warm-up temperature and the welding line clearance. By quadratic general revolving combination design, the mathematics equation indicating the relation of welding tensile stress, warm-up temperature, pressing time and welding line clearance was obtained, and the optimized welding parameters to achieve the best tensile strength were decided as well. By further analysis on microstructures and fractures of welded seam, fusion zone and HAZ of thermit steel, conclusion was made that it was of vital significance to adopt welding-after-peening method for improving the strength of the welded seam.
查看更多>>摘要：As a bridge between top-level transaction and low-level control system of facilities, MES (Manufacturing Execution System) is the key technology to implement the integration of all enterprise information systems. The research on MES oriented to agile manufacturing is of great importance in improving the level of management and automation. This paper is a brief introduction to the features of MES and its key technologies based on agile manufacturing environment. In view of the advanced technology and its practicability and feasibility, the methodology of software reuse is employed to study MES oriented to agile manufacturing. Meanwhile, the author analyses its key technologies, proposes an integration framework of MES oriented to agile manufacturing which can realize the horizontal integration and vertical integration for MES by adopting agent components, and presents a solution to MES's implementation for the agile manufacturing company.
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