Applied Mechanics and Materials Vols. 80-81

Abstract: In this paper, a new classification equipment for Bauxite desiliconization is introduced, which combines Centrifugal with gravity and it can separate diaspore and slime effectively in a composite force; The flow field in the equipment was simulated by Fluent software for explaining separation process and principle; the laboratory experiments and pilot tests had been finished on this kind of device, showing that a concentrate with Al₂O₃ recovery of 90.64% and Al-Si ratio of 6.34 was obtained from the feed with a Al/Si ratio of 4.7 based on one stage desiliconization separation; the pilot tests show that new classification equipment for Bauxite desiliconization can increase the concentration with Al₂O₃ recovery by 1.59 percent and Al-Si ratio by 0.19 and degrease the Al-Si ratio of tailing by 0.39. The separation index of the new separator is better than the general separator obviously.

Abstract: There are many varieties of materials and suppliers for the PCB assembly process; meanwhile, process modifications as well as order changings happen frequently during production. The PCB assembly industry is suffering uncertainty and unknowingness due to the lack of timely, accurate, and consistent production data. Therefore, real-time production information tracking plays an important role for the PCB assembly industry, which provides the right information to the right person at right time to support the decision making and optimize the production management. This paper applies RFID technology to capture the production data and process production information for PCB assembly enterprises. In a PCB assembly line, machines and materials are equipped with RFID device such as RFID readers and tags to build the real-time data collecting environment. A number of production information processing methods are proposed to extract the production tracking information such as progress, WIP (Work-in-progress) inventory from the mass real-time data through data filtering and selection. Finally, a case study is given to demonstrate the developed methodologies.

Abstract: Job scheduling and AGV scheduling in FMS are regarded as two independent problems by most researchers. Their isolation ignores AGV’s use conflicts in the job scheduling and leads to low average equipment utilization. We point out the necessity for the job scheduling to integrate with AGV scheduling through analyzing scheduling problem of a specific type of FMS with single AGV and single buffer area. Then a corresponding mathematic model for integrated scheduling is presented based on the problem description and constraints for scheduling. A specific FMS is adopted to validate this integrated scheduling model. Based on data from this FMS, the model is performed through genetic algorithm with appropriate parameters. And job’s processing sequences as well as AGV’s moving path are obtained from the optimal gene order. The experiment result of this scheduling model adopting genetic algorithm shows good computing efficiency and equipment utilization.

Abstract: Cuprum and aluminium are common thermal conductive materials in daily life. Thermal contact resistance is quite complex and depends on many parameters including surface characteristics of the interfacial region, temperature and contact pressure. In this paper, experimental equipment is invented and different working conditions are designed for studying the relationship of thermal contact resistance and temperature between cuprum and aluminium. Experimental results showed that thermal contact resistance will decrease obviously in a period of temperature, and after that period, thermal contact resistance will almost be a constant. These results would be a certain benefit to practical application of cuprum and aluminum.

Abstract: The accuracy of edge detection determines the accuracy of actual dimension measurement，in order to improve the measuring accuracy, this paper proposes a fast algorithm of detecting the glass bottle dimension based on Zernike moments. Firstly, combines the traditional Zernike moment-based method with Otsu adaptive threshold algorithm and a new fast algorithm for edge detection is proposed. Then uses this fast algorithm to detect the edge of glass bottle with subpixel-level and uses the least square method to fit ellipses formed by the glass bottle mouth and bottom. Calibrated the system with standard gauge block and obtain the actual dimension at last. Experimental results show that the improved algorithm not only can make the edge detection reach the subpixel-level accuracy, but also can avoid the edge misidentification and inefficient causing by repeatedly manual adjustments to select the threshold value when detecting the edge. Making a rapid, accurate, non-contact measuring system becomes a reality.

Abstract: Swarm intelligence has been the new method to resolve traditional structure optimization problem. Group cooperative system composed by individual robots will complete task which individual robot cannot do by coordinating each other and cooperating mutually. From worldwide advances in the researches of groups-robot cooperation system and typical groups-robot cooperation system, we can see meta trends of researches into groups-robot cooperation system and difficulties restrict development and translation to utility system of groups-robot cooperation system. The future coming burning issue will be how to build up the groups-robot cooperation system of higher robustness and adaptability in the face of the true environment with characteristics of unstructured and dynamic.