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
[ 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
为了在模型参数先验分布知识未知情况下实现基于区域和统计的图像分割,并同时获取更加精确的模型参数,提出了一种结合Voronoi划分技术、最大期望值(Expectation Maximization,EM)和最大边缘概率(Maximizationof the Posterior Marginal,...为了在模型参数先验分布知识未知情况下实现基于区域和统计的图像分割,并同时获取更加精确的模型参数,提出了一种结合Voronoi划分技术、最大期望值(Expectation Maximization,EM)和最大边缘概率(Maximizationof the Posterior Marginal,MPM)算法的图像分割方法。该方法利用Voronoi划分技术将图像域划分为若干子区域,待分割图像中的同质区域可以由一组子区域拟合而成,并假定各同质区域内像素强度服从同一独立的正态分布,从而建立图像模型,然后结合EM/MPM算法进行图像分割和模型参数估计,其中,MPM算法用于实现面向同质区域的图像分割,EM算法用于估计图像模型参数。为了验证提出的图像分割方法,分别对合成图像和真实图像进行了分割实验,并和传统的基于像素的MRF分割结果进行对比,测试结果的定性和定量分析表明了该方法的有效性和准确性。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。
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.
文摘为了在模型参数先验分布知识未知情况下实现基于区域和统计的图像分割,并同时获取更加精确的模型参数,提出了一种结合Voronoi划分技术、最大期望值(Expectation Maximization,EM)和最大边缘概率(Maximizationof the Posterior Marginal,MPM)算法的图像分割方法。该方法利用Voronoi划分技术将图像域划分为若干子区域,待分割图像中的同质区域可以由一组子区域拟合而成,并假定各同质区域内像素强度服从同一独立的正态分布,从而建立图像模型,然后结合EM/MPM算法进行图像分割和模型参数估计,其中,MPM算法用于实现面向同质区域的图像分割,EM算法用于估计图像模型参数。为了验证提出的图像分割方法,分别对合成图像和真实图像进行了分割实验,并和传统的基于像素的MRF分割结果进行对比,测试结果的定性和定量分析表明了该方法的有效性和准确性。
