自主机器人定位中,从激光雷达扫描数据提取出精确的环境特征将能大幅提高即时定位与构图(Simultaneous localization and mapping,SLAM)技术中匹配的速度。目前,特征提取算法大多采用迭代计算的方法,计算复杂度高,计算量较大。针对此问...自主机器人定位中,从激光雷达扫描数据提取出精确的环境特征将能大幅提高即时定位与构图(Simultaneous localization and mapping,SLAM)技术中匹配的速度。目前,特征提取算法大多采用迭代计算的方法,计算复杂度高,计算量较大。针对此问题,提出了一种角点特征的提取方法。该方法避免了迭代计算,通过角点定位对分割结果进行修正,在保证精度的前提下,使用两点拟合直线代替了最小二乘法。首先,使用激光雷达获得的扫描点对应矢径长度和角度,计算相邻点的斜率差,对点集进行初始分割。然后,计算分割后每部分点集对应线段的斜率,对过分割的点集进行合并。最后,通过计算相邻两直线的交点对角点特征进行定位和提取。通过实验验证,该算法能够准确地提取出数据帧中的角点特征,并且具有较好的位置精度和计算效率。展开更多
OBJECTIVE: To observe capillary blood flow at acupoints during acupuncture treatment of primary dysmenorrhea and gain new insights into its analgesic mechanism. METHODS: Patients with primary dysmenorrhea were enrolle...OBJECTIVE: To observe capillary blood flow at acupoints during acupuncture treatment of primary dysmenorrhea and gain new insights into its analgesic mechanism. METHODS: Patients with primary dysmenorrhea were enrolled and randomly assigned to a treatment or control group. Subjects' symptoms were differentiated into variousTraditional Chinese Medicine(TCM) syndromes and treated for 10 sessions with puncturing acupuncture or self-pressing right-hand Hegu(LI 4), adding other acupoints based on syndrome. Laser speckle was used to compare the change in the vasomotor amplitude and perfusion of the capillaries in Hegu(LI 4) before and during the treatment. Each subject was required to finish the period pain symptoms observation form, verbal rating scales, numerical rating scale, pain rating index, face rating scale, Zung self-rating depression scale, Zung self-rating anxiety scale, and numerical rating scale before and after treatments. RESULTS: After 10 sessions, the symptom scores, pain index(PI), and visual analog scale(VAS) decreased significantly in treatment group. The volume of blood flow in Hegu(LI 4) declined slightly. No significant evidence supported that needling caused capillary contraction, but the capillary vasomotor amplitude at Hegu(LI 4) increased remarkably. CONCLUSION: Acupuncture can increase the capillary blood flow, thus promoting the flow of Qi and blood in terms of TCM theory, which facilitates pain relief.展开更多
It is necessary that the laser inertial system is used to further improve the fire accuracy and quick reaction capability in the ballistic missile strapdown inertial navigation system. According to the guidance contro...It is necessary that the laser inertial system is used to further improve the fire accuracy and quick reaction capability in the ballistic missile strapdown inertial navigation system. According to the guidance controlling method and the output and error model of ballistic missile laser SIMU, the mathematical model of error propagation mechanism is set up and any transfer environmental function of error coefficient that affects the fire accuracy is deduced. Also, the missile longitudinal/lateral impact point is calculated using MATLAB. These establish the technical foundation for further researching the dispersion characteristics of impact point and reducing the laser guidance error.展开更多
文摘自主机器人定位中,从激光雷达扫描数据提取出精确的环境特征将能大幅提高即时定位与构图(Simultaneous localization and mapping,SLAM)技术中匹配的速度。目前,特征提取算法大多采用迭代计算的方法,计算复杂度高,计算量较大。针对此问题,提出了一种角点特征的提取方法。该方法避免了迭代计算,通过角点定位对分割结果进行修正,在保证精度的前提下,使用两点拟合直线代替了最小二乘法。首先,使用激光雷达获得的扫描点对应矢径长度和角度,计算相邻点的斜率差,对点集进行初始分割。然后,计算分割后每部分点集对应线段的斜率,对过分割的点集进行合并。最后,通过计算相邻两直线的交点对角点特征进行定位和提取。通过实验验证,该算法能够准确地提取出数据帧中的角点特征,并且具有较好的位置精度和计算效率。
基金Supported by National Natural Science Foundation(No.81072760)Sino-Austrian Science and Technology Collaboration Program of the Ministry of Science and Technology of the People's Republic of China(ZZ04007)Foundation for Excellent Returnees of Ministry of Human Resources and Social Security of the People's Republic of China,and Research on Specificity of Vasomotor Micrangium in Acupoints Transmitted along Meridians[National Program on Key Basic Research Project(973 Program),2012CB518502]
文摘OBJECTIVE: To observe capillary blood flow at acupoints during acupuncture treatment of primary dysmenorrhea and gain new insights into its analgesic mechanism. METHODS: Patients with primary dysmenorrhea were enrolled and randomly assigned to a treatment or control group. Subjects' symptoms were differentiated into variousTraditional Chinese Medicine(TCM) syndromes and treated for 10 sessions with puncturing acupuncture or self-pressing right-hand Hegu(LI 4), adding other acupoints based on syndrome. Laser speckle was used to compare the change in the vasomotor amplitude and perfusion of the capillaries in Hegu(LI 4) before and during the treatment. Each subject was required to finish the period pain symptoms observation form, verbal rating scales, numerical rating scale, pain rating index, face rating scale, Zung self-rating depression scale, Zung self-rating anxiety scale, and numerical rating scale before and after treatments. RESULTS: After 10 sessions, the symptom scores, pain index(PI), and visual analog scale(VAS) decreased significantly in treatment group. The volume of blood flow in Hegu(LI 4) declined slightly. No significant evidence supported that needling caused capillary contraction, but the capillary vasomotor amplitude at Hegu(LI 4) increased remarkably. CONCLUSION: Acupuncture can increase the capillary blood flow, thus promoting the flow of Qi and blood in terms of TCM theory, which facilitates pain relief.
文摘It is necessary that the laser inertial system is used to further improve the fire accuracy and quick reaction capability in the ballistic missile strapdown inertial navigation system. According to the guidance controlling method and the output and error model of ballistic missile laser SIMU, the mathematical model of error propagation mechanism is set up and any transfer environmental function of error coefficient that affects the fire accuracy is deduced. Also, the missile longitudinal/lateral impact point is calculated using MATLAB. These establish the technical foundation for further researching the dispersion characteristics of impact point and reducing the laser guidance error.