微波功率模块(Microwave Power Module,MPM)是电真空发射机的发展方向之一,目前MPM饱和功率量级在百瓦量级。为保障系统工作稳定性和判断MPM的输出能效,需要MPM具有实时监测输出功率的能力。文章提出了一种在行波管输出端增加耦合口的...微波功率模块(Microwave Power Module,MPM)是电真空发射机的发展方向之一,目前MPM饱和功率量级在百瓦量级。为保障系统工作稳定性和判断MPM的输出能效,需要MPM具有实时监测输出功率的能力。文章提出了一种在行波管输出端增加耦合口的方案来监测输出功率。相比传统通过定向耦合器测试功率的方案,该方案具有高效率、小型化、低成本、高可靠性等特点。展开更多
基于区域和统计的SAR分割方法,提出一种结合Voronoi划分技术、最大期望值EM(Expectation Maximization)和最大边缘概率MPM(Maximization of the Posterior Marginal)算法的多视SAR图像分割方法。首先利用Voronoi划分将图像域划分成不同...基于区域和统计的SAR分割方法,提出一种结合Voronoi划分技术、最大期望值EM(Expectation Maximization)和最大边缘概率MPM(Maximization of the Posterior Marginal)算法的多视SAR图像分割方法。首先利用Voronoi划分将图像域划分成不同的子区域,而每个子区域可以被看成待分割同质区域的一个组成部分,并假设每个子区域内的像素满足同一独立的Gamma分布,从而建立多视SAR图像模型,并在贝叶斯理论架构下建立图像分割模型,然后结合EM/MPM算法进行图像分割和模型参数估计。该方法将基于像元的马尔可夫随机场(Markov Random Field,MRF)模型扩展到基于区域的MRF模型,并且能同时有效地获取模型参数估计和基于区域的SAR图像最优分割。采用本文算法,分别对RADARSAT-Ⅰ/ⅡSAR强度图像和合成SAR强度图像进行了分割实验,定性和定量的测试结果验证了本文方法的有效性、可靠性和准确性。展开更多
[ Objective] The experiment aimed to clone Paramyosin/mini-Paramyosin (PM/mPM) gene to analyze the relations between it and moving behaviors. [Method] PCR method and RACE technology were used to obtain whole cDNA of...[ Objective] The experiment aimed to clone Paramyosin/mini-Paramyosin (PM/mPM) gene to analyze the relations between it and moving behaviors. [Method] PCR method and RACE technology were used to obtain whole cDNA of PM and some cDNA of mPM of Bombyx moil. By comparing wgs of Bombyx mori, the genomic sequence of PM/mPM of Bombyx mori was obtained, and, their genome structure was determined. [ Result] PM/mPM genes consisted of 17 exons and 16 intrens. By the use of selective promoters, The gene sequence encoded PM and mPM, while PM and mPM shared the last 6 exons. The cluster analysis between PM of Bombyx mori and PM of other invertebrate animals demonstrated that the relation between Bombyx mori and Bombyx mandarina was closest and the relation between Bombyx mori and Drosophila melanogaster was farthest in Insecta. [ Conclusion] There was no point mutation which could influence flight in amino acid sequence of PM of Bombyx mori and Bombyx mandarina, so the difference of flight capacity of Bombyx mori and Bombyx mandarina might be regulated by other mechanism.展开更多
文摘微波功率模块(Microwave Power Module,MPM)是电真空发射机的发展方向之一,目前MPM饱和功率量级在百瓦量级。为保障系统工作稳定性和判断MPM的输出能效,需要MPM具有实时监测输出功率的能力。文章提出了一种在行波管输出端增加耦合口的方案来监测输出功率。相比传统通过定向耦合器测试功率的方案,该方案具有高效率、小型化、低成本、高可靠性等特点。
文摘基于区域和统计的SAR分割方法,提出一种结合Voronoi划分技术、最大期望值EM(Expectation Maximization)和最大边缘概率MPM(Maximization of the Posterior Marginal)算法的多视SAR图像分割方法。首先利用Voronoi划分将图像域划分成不同的子区域,而每个子区域可以被看成待分割同质区域的一个组成部分,并假设每个子区域内的像素满足同一独立的Gamma分布,从而建立多视SAR图像模型,并在贝叶斯理论架构下建立图像分割模型,然后结合EM/MPM算法进行图像分割和模型参数估计。该方法将基于像元的马尔可夫随机场(Markov Random Field,MRF)模型扩展到基于区域的MRF模型,并且能同时有效地获取模型参数估计和基于区域的SAR图像最优分割。采用本文算法,分别对RADARSAT-Ⅰ/ⅡSAR强度图像和合成SAR强度图像进行了分割实验,定性和定量的测试结果验证了本文方法的有效性、可靠性和准确性。
基金Supported by the National High Technology Research and Development Program of China(863 Program)(No.2006AA10A118)~~
文摘[ Objective] The experiment aimed to clone Paramyosin/mini-Paramyosin (PM/mPM) gene to analyze the relations between it and moving behaviors. [Method] PCR method and RACE technology were used to obtain whole cDNA of PM and some cDNA of mPM of Bombyx moil. By comparing wgs of Bombyx mori, the genomic sequence of PM/mPM of Bombyx mori was obtained, and, their genome structure was determined. [ Result] PM/mPM genes consisted of 17 exons and 16 intrens. By the use of selective promoters, The gene sequence encoded PM and mPM, while PM and mPM shared the last 6 exons. The cluster analysis between PM of Bombyx mori and PM of other invertebrate animals demonstrated that the relation between Bombyx mori and Bombyx mandarina was closest and the relation between Bombyx mori and Drosophila melanogaster was farthest in Insecta. [ Conclusion] There was no point mutation which could influence flight in amino acid sequence of PM of Bombyx mori and Bombyx mandarina, so the difference of flight capacity of Bombyx mori and Bombyx mandarina might be regulated by other mechanism.