The objective of this research is to reduce waste in the production ceramics of Ceramics Factory in Thailand. The 7 Quality Control Tools （7 QC Tools） were implemented including Check sheet, Graph, Pareto diagram an...The objective of this research is to reduce waste in the production ceramics of Ceramics Factory in Thailand. The 7 Quality Control Tools （7 QC Tools） were implemented including Check sheet, Graph, Pareto diagram and Fishbone diagram, which were used to analyze and solve the problems. It was found that most of the wastes come from burning ceramics process. The kilns and trolleys has been used for a long time. Furthermore, the equipment and parts were damaged from lack of maintenance. The non-standard of product arrangement method into the kilns were the cause of waste. Thus, the researcher improved trolleys into the kilns and designed a fixture to help worker to product arrangement. The results of the research gathered data from quality inspection department. Then comparing data before the improvement （between September 2013 to December 2013） and after the improvement （between November 2014 to February 2015）, the wastes are reduced from 8.97% to 0.29%. The result of improving is very efficiency because it can reduce the wastes by 8.68%.展开更多
A novel backoff algorithm in CSMA/CA-based medium access control (MAC) protocols for clustered sensor networks was proposed. The algorithm requires that all sensor nodes have the same value of contention window (CW) i...A novel backoff algorithm in CSMA/CA-based medium access control (MAC) protocols for clustered sensor networks was proposed. The algorithm requires that all sensor nodes have the same value of contention window (CW) in a cluster, which is revealed by formulating resource allocation as a network utility maximization problem. Then, by maximizing the total network utility with constrains of minimizing collision probability, the optimal value of CW (Wopt) can be computed according to the number of sensor nodes. The new backoff algorithm uses the common optimal value Wopt and leads to fewer collisions than binary exponential backoff algorithm. The simulation results show that the proposed algorithm outperforms standard 802.11 DCF and S-MAC in average collision times, packet delay, total energy consumption, and system throughput.展开更多
文摘The objective of this research is to reduce waste in the production ceramics of Ceramics Factory in Thailand. The 7 Quality Control Tools （7 QC Tools） were implemented including Check sheet, Graph, Pareto diagram and Fishbone diagram, which were used to analyze and solve the problems. It was found that most of the wastes come from burning ceramics process. The kilns and trolleys has been used for a long time. Furthermore, the equipment and parts were damaged from lack of maintenance. The non-standard of product arrangement method into the kilns were the cause of waste. Thus, the researcher improved trolleys into the kilns and designed a fixture to help worker to product arrangement. The results of the research gathered data from quality inspection department. Then comparing data before the improvement （between September 2013 to December 2013） and after the improvement （between November 2014 to February 2015）, the wastes are reduced from 8.97% to 0.29%. The result of improving is very efficiency because it can reduce the wastes by 8.68%.
基金Project(60772088) supported by the National Natural Science Foundation of China
文摘A novel backoff algorithm in CSMA/CA-based medium access control (MAC) protocols for clustered sensor networks was proposed. The algorithm requires that all sensor nodes have the same value of contention window (CW) in a cluster, which is revealed by formulating resource allocation as a network utility maximization problem. Then, by maximizing the total network utility with constrains of minimizing collision probability, the optimal value of CW (Wopt) can be computed according to the number of sensor nodes. The new backoff algorithm uses the common optimal value Wopt and leads to fewer collisions than binary exponential backoff algorithm. The simulation results show that the proposed algorithm outperforms standard 802.11 DCF and S-MAC in average collision times, packet delay, total energy consumption, and system throughput.
