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量子阱控制极和异质谷间转移电子三极管初探 被引量:1
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作者 薛舫时 《半导体杂志》 1997年第4期1-8,31,共9页
介绍了能带混合量子阱中的多能谷混合和异质谷间转移电子效应。运用这一新物理效应设计制成了新的异质谷间转移电子器件。通过二极管的振荡和放大性能测试从实验上研究了能带混合量子阱的触发和控制功能。运用能带混合隧穿共振理论和M... 介绍了能带混合量子阱中的多能谷混合和异质谷间转移电子效应。运用这一新物理效应设计制成了新的异质谷间转移电子器件。通过二极管的振荡和放大性能测试从实验上研究了能带混合量子阱的触发和控制功能。运用能带混合隧穿共振理论和MonteCarlo输运模拟分析了新器件的动态工作模式和量子阱控制极的控制功能。最后讨论了使用量子阱控制极的新控制功能来制作新的转移电子三极管的可能性。 展开更多
关键词 异质价间 转换电子器件 量子阱 控制三极管
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A Method for Spatial Heterogeneity Evaluation on Landscape Pattern of Farmland Shelterbelt Networks:A Case Study in Midwest of Jilin Province,China 被引量:12
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作者 SHI Xiaoliang LI Ying DENG Rongxin 《Chinese Geographical Science》 SCIE CSCD 2011年第1期48-56,共9页
On the basis of landscape ecology, combining the Spot 5 high resolution satellite imagery with GIS, a method evaluating the spatial heterogeneity of shelterbelts distribution at landscape scale is put forward in this ... On the basis of landscape ecology, combining the Spot 5 high resolution satellite imagery with GIS, a method evaluating the spatial heterogeneity of shelterbelts distribution at landscape scale is put forward in this paper. The distance coefficients of reasonable and existing landscape indexes of farmland shelterbelt networks were com-puted, and then through the classification of the distance coefficients, and the establishment of evaluation rules, the spatial heterogeneity of farmland shelterbelts was evaluated. The method can improve the evaluating system of previ-ous studies on shelterbelts distribution, resolve the disadvantages of lacking spatiality of overall evaluation, and make the evaluation results have more directive significance for shelterbelt management. Based on this method, spatial het-erogeneity of shelterbelt networks was evaluated in the midwest of Jilin Province, China. The results show that the re-gions with fewer shelterbelts and no closed network account for 34.7% of the total area, but only 4.9% of the area has relative reasonable pattern of shelterbelt networks. Many problems exist in the distribution pattern of shelterbelts, therefore, much attention should be paid to construct farmland shelterbelts in the study area. 展开更多
关键词 farmland shelterbelt spatial heterogeneity Spot 5 distance coefficient
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