回环检测作为同步建图与定位(Simulation Localization and Mapping,SLAM)算法中的基本组成部分,能有效关联相同场景之间的特征信息,提供全局一致性的位姿估计。基于词袋(Bag of Words,BoW)模型的回环检测算法在视觉SLAM领域有着显著成...回环检测作为同步建图与定位(Simulation Localization and Mapping,SLAM)算法中的基本组成部分,能有效关联相同场景之间的特征信息,提供全局一致性的位姿估计。基于词袋(Bag of Words,BoW)模型的回环检测算法在视觉SLAM领域有着显著成效,但对于激光雷达SLAM算法,主流的方法无法实时有效地识别回环场景,且通常无法校正完整的六自由度(6 Degree of Freedom,6-DOF)环路姿态。针对以上问题,文章提出了一种基于线性关键点特征表示的词袋模型,用于激光雷达SLAM中的实时回环检测。该词袋模型计算性能高效,可满足自动驾驶实时性要求。同时,算法具有稳定的姿态校正能力,可用于精确的点对点匹配。在公开数据集上,将文章提出的方法嵌入激光SLAM算法中进行闭环性能评估。结果表明,基于词袋模型的回环检测算法在激光SLAM领域优于现有的主流方法。展开更多
[Objective] This study was to investigate the effect of forsythiaside A added in chick embryo kidney cells (CEKs), on the changes in expression of interferon α(IFN-α) and mRNA expression level of correlated factors ...[Objective] This study was to investigate the effect of forsythiaside A added in chick embryo kidney cells (CEKs), on the changes in expression of interferon α(IFN-α) and mRNA expression level of correlated factors in JAK-STAT pathway. [Methods] Three levels of forsythiaside (100, 200, 400 μg/ml) were adopted to treat the experimental materials, then the expression levels of IFN-α and correlated factors in JAK-STAT pathway were detected by real-time RT-PCR at the transcriptional level (mRNA) and by Western blot at the translation level(IFN-α protein). [Result] Compared with the control group (untreated group), Application of forsythiaside A not only significantly increased the expression of IFN-α in treated CEKs (P<0.05) , but also up-regulated the expression of STAT1, JAK1, IFNAR1, IFNAR2, IRF1 and IRF7, the correlated factors in JAK-STAT pathway. [Conclusion] Forsythiaside A induced the expression of IFN-α in CEKs, and can positively regulate the JAK-STAT signaling pathway significantly.展开更多
This paper has proposed a new methodology extracting stability classes of field association words depending on automatically power link analysis to enhance the precision of decision tree. In this paper, we have studie...This paper has proposed a new methodology extracting stability classes of field association words depending on automatically power link analysis to enhance the precision of decision tree. In this paper, we have studied the effects of the time variation based on the frequencies of specific words called field association words that connected to documents using power link in a specific period. The stability classes have referred to the popularity of field association words based on the change of time in a given period. The new approach has evaluated by conducting experiments simulating results of 1575 files (about 5.16 MB). Based on these experiments, it has turned out that, the F-measure for ascending, stable and descending classes have achieved 93.6%, 99.8% and 75.7%, respectively. These results mean that F-measure was increasing by 12%, 4% and 34% than traditional methods because of the power link analysis.展开更多
文摘回环检测作为同步建图与定位(Simulation Localization and Mapping,SLAM)算法中的基本组成部分,能有效关联相同场景之间的特征信息,提供全局一致性的位姿估计。基于词袋(Bag of Words,BoW)模型的回环检测算法在视觉SLAM领域有着显著成效,但对于激光雷达SLAM算法,主流的方法无法实时有效地识别回环场景,且通常无法校正完整的六自由度(6 Degree of Freedom,6-DOF)环路姿态。针对以上问题,文章提出了一种基于线性关键点特征表示的词袋模型,用于激光雷达SLAM中的实时回环检测。该词袋模型计算性能高效,可满足自动驾驶实时性要求。同时,算法具有稳定的姿态校正能力,可用于精确的点对点匹配。在公开数据集上,将文章提出的方法嵌入激光SLAM算法中进行闭环性能评估。结果表明,基于词袋模型的回环检测算法在激光SLAM领域优于现有的主流方法。
文摘[Objective] This study was to investigate the effect of forsythiaside A added in chick embryo kidney cells (CEKs), on the changes in expression of interferon α(IFN-α) and mRNA expression level of correlated factors in JAK-STAT pathway. [Methods] Three levels of forsythiaside (100, 200, 400 μg/ml) were adopted to treat the experimental materials, then the expression levels of IFN-α and correlated factors in JAK-STAT pathway were detected by real-time RT-PCR at the transcriptional level (mRNA) and by Western blot at the translation level(IFN-α protein). [Result] Compared with the control group (untreated group), Application of forsythiaside A not only significantly increased the expression of IFN-α in treated CEKs (P<0.05) , but also up-regulated the expression of STAT1, JAK1, IFNAR1, IFNAR2, IRF1 and IRF7, the correlated factors in JAK-STAT pathway. [Conclusion] Forsythiaside A induced the expression of IFN-α in CEKs, and can positively regulate the JAK-STAT signaling pathway significantly.
文摘This paper has proposed a new methodology extracting stability classes of field association words depending on automatically power link analysis to enhance the precision of decision tree. In this paper, we have studied the effects of the time variation based on the frequencies of specific words called field association words that connected to documents using power link in a specific period. The stability classes have referred to the popularity of field association words based on the change of time in a given period. The new approach has evaluated by conducting experiments simulating results of 1575 files (about 5.16 MB). Based on these experiments, it has turned out that, the F-measure for ascending, stable and descending classes have achieved 93.6%, 99.8% and 75.7%, respectively. These results mean that F-measure was increasing by 12%, 4% and 34% than traditional methods because of the power link analysis.
