This paper analyzes the characteristics of the output gradient histogram and shortages of several traditional automatic threshold methods in order to segment the gradient image better. Then an improved double-threshol...This paper analyzes the characteristics of the output gradient histogram and shortages of several traditional automatic threshold methods in order to segment the gradient image better. Then an improved double-threshold method is proposed, which is combined with the method of maximum classes variance, estimating-area method and double-threshold method. This method can automatically select two different thresholds to segment gradient images. The computer simulation is performed on the traditional methods and this algorithm and proves that this method can get satisfying result. Key words gradient histogram image - threshold selection - double-threshold method - maximum classes variance method CLC number TP 391. 41 Foundation item: Supported by the National Nature Science Foundation of China (50099620) and the Project of Chenguang Plan in Wuhan (985003062)Biography: YANG Shen (1977-), female, Ph. D. candidate, research direction: multimedia information processing and network technology.展开更多
The carbon nanobeads were prepared through high temperature pyrolysis and deposition from phthalocyanine. After surface's functionalization treatment of the carbon beads, the carbon nanobeads supported Pt catalyst...The carbon nanobeads were prepared through high temperature pyrolysis and deposition from phthalocyanine. After surface's functionalization treatment of the carbon beads, the carbon nanobeads supported Pt catalyst was produced. The Pt/C catalyst was characterized by SEM, TEM, Raman spectrum, EDS and XRD methods. Combining the carbonaceous paper spreaded up with the catalyst with Nafion membrane, we made MEA electrode. The discharge curves indicated that this carbon nanobeads supported Pt is a good fuel cell catalyst with excellent performance, high activity and sign of a long-time life.展开更多
文摘This paper analyzes the characteristics of the output gradient histogram and shortages of several traditional automatic threshold methods in order to segment the gradient image better. Then an improved double-threshold method is proposed, which is combined with the method of maximum classes variance, estimating-area method and double-threshold method. This method can automatically select two different thresholds to segment gradient images. The computer simulation is performed on the traditional methods and this algorithm and proves that this method can get satisfying result. Key words gradient histogram image - threshold selection - double-threshold method - maximum classes variance method CLC number TP 391. 41 Foundation item: Supported by the National Nature Science Foundation of China (50099620) and the Project of Chenguang Plan in Wuhan (985003062)Biography: YANG Shen (1977-), female, Ph. D. candidate, research direction: multimedia information processing and network technology.
文摘The carbon nanobeads were prepared through high temperature pyrolysis and deposition from phthalocyanine. After surface's functionalization treatment of the carbon beads, the carbon nanobeads supported Pt catalyst was produced. The Pt/C catalyst was characterized by SEM, TEM, Raman spectrum, EDS and XRD methods. Combining the carbonaceous paper spreaded up with the catalyst with Nafion membrane, we made MEA electrode. The discharge curves indicated that this carbon nanobeads supported Pt is a good fuel cell catalyst with excellent performance, high activity and sign of a long-time life.
