The great attention has been paid to the mini-invasive methods of the distribution of the malignant process in the thoracic and abdominal cavities for last time. In the Thoracic department of the Republican Research O...The great attention has been paid to the mini-invasive methods of the distribution of the malignant process in the thoracic and abdominal cavities for last time. In the Thoracic department of the Republican Research Oncological Centre of the Republic of Uzbekistan during the period from 2004 to 2008 in the plan of investigation of the patients with esophageal and stomach cancer including roentgenoscopy and (or) roentgenography of the thoracic chest, contrast esophageal and stomach roentgenoscopy, EPGDS and ultrasonography of the mediastinal and abdominal cavity organs additionally computed tomography and diagnostic thoraco-and (or) laparoscopy were included. The cancer of mesothoracic esophageal part with invasion into the upper thoracic part was diagnosed in 2 patients, the cancer of mesothoracic esophageal part-in 12 patients, the cancer of the middle and the lower parts-in 7 patients, the cancer the lower thorax part-in 7 patients, the cardioesophageal cancer-in 9 patients, a total cancer of a stomach with affection of the bottom third of the oesophagus-in 1 patient. Thoracoscopy and laparoscopy allow determination of the respectability of the tumorous process in the esophageal and stomach cancer considerably lowering the number of exploratory thoracotomies and laparotomies.展开更多
针对局部均值分解(Local Mean Decomposition,LMD)算法应用于电能质量扰动检测时存在“端点效应”与滑动平均收敛速度慢,严重影响测量精度的问题,提出一种改进局部均值分解方法(Modified LMD,MLMD)。通过分段三次Hermite插值取代滑动平...针对局部均值分解(Local Mean Decomposition,LMD)算法应用于电能质量扰动检测时存在“端点效应”与滑动平均收敛速度慢,严重影响测量精度的问题,提出一种改进局部均值分解方法(Modified LMD,MLMD)。通过分段三次Hermite插值取代滑动平均法,有效改善LMD收敛慢、受平滑长度影响的弊端。为避免延拓长度不够而导致的“延拓失败”情形,在镜像延拓法的基础上结合“奇延拓”方法提出改进镜像延拓法。针对“直接法”求频率存在“毛刺现象”的弊端,文中改用希尔伯特变换(Hilbert Transform,HT)求取瞬时频率。最后,将MLMD分别应用于单一扰动信号与复合谐波信号的检测,相较传统的经验模态分解方法(Empirical Mode Decomposition,EMD),MLMD方法可有效抑制“端点效应”,同时能更准确的定位扰动信号的起止时刻,并且对高次谐波信号有更好的提取能力。展开更多
In cooperative localization with sparse communication networks, an agent maybe only receives part of locating messages from the others. It is difficult for the receiver to utilize the part instead of global knowledge....In cooperative localization with sparse communication networks, an agent maybe only receives part of locating messages from the others. It is difficult for the receiver to utilize the part instead of global knowledge. Under the extended Kalman filtering, the utilization of the locating message is maximized by two aspects: the locating message generating and multi-locating messages fusing. For the former, the covariance upper-bound technique, by introducing amplification coefficients, is employed to remove the dependency of locating messages on the global knowledge. For the latter, an optimization model is setup; the covariance matrix determinant of the receiver's state estimate, expressed as a function of the amplification coefficients, is selected as the optimization criterion, under linear constraints on the amplification coefficient characteristics and the communication connectivity. Using the optimization solution, the local optimal state of the receiver agent is obtained by the weighting fusion. Simulation with seven agents is shown to evaluate the effectiveness of the proposed algorithm.展开更多
A new method for speeding up the state augment operations involved in the compressed extended Kalman filter-based simultaneous localization and mapping (CEKF-SLAM) algorithm was proposed. State augment usually requi...A new method for speeding up the state augment operations involved in the compressed extended Kalman filter-based simultaneous localization and mapping (CEKF-SLAM) algorithm was proposed. State augment usually requires a fully-updated state eovariance so as to append the information of newly observed landmarks, thus computational volume increases quadratically with the number of landmarks in the whole map. It was proved that state augment can also be achieved by augmenting just one auxiliary coefficient ma- trix. This method can yield identical estimation results as those using EKF-SLAM algorithm, and computa- tional amount grows only linearly with number of increased landmarks in the local map. The efficiency of this quick state augment for CEKF-SLAM algorithm has been validated by a sophisticated simulation project.展开更多
In this paper a label-based simultaneous localization and mapping( SLAM) system is proposed to provide localization to indoor autonomous robots. In the system quick response( QR) codes encoded with serial numbers ...In this paper a label-based simultaneous localization and mapping( SLAM) system is proposed to provide localization to indoor autonomous robots. In the system quick response( QR) codes encoded with serial numbers are utilized as labels. These labels are captured by two webcams,then the distances and angles between the labels and webcams are computed. Motion estimated from the two rear wheel encoders is adjusted by observing QR codes. Our system uses the extended Kalman filter( EKF) for the back-end state estimation. The number of deployed labels controls the state estimation dimension. The label-based EKF-SLAM system eliminates complicated processes,such as data association and loop closure detection in traditional feature-based visual SLAM systems. Our experiments include software-simulation and robot-platform test in a real environment. Results demonstrate that the system has the capability of correcting accumulated errors of dead reckoning and therefore has the advantage of superior precision.展开更多
文摘The great attention has been paid to the mini-invasive methods of the distribution of the malignant process in the thoracic and abdominal cavities for last time. In the Thoracic department of the Republican Research Oncological Centre of the Republic of Uzbekistan during the period from 2004 to 2008 in the plan of investigation of the patients with esophageal and stomach cancer including roentgenoscopy and (or) roentgenography of the thoracic chest, contrast esophageal and stomach roentgenoscopy, EPGDS and ultrasonography of the mediastinal and abdominal cavity organs additionally computed tomography and diagnostic thoraco-and (or) laparoscopy were included. The cancer of mesothoracic esophageal part with invasion into the upper thoracic part was diagnosed in 2 patients, the cancer of mesothoracic esophageal part-in 12 patients, the cancer of the middle and the lower parts-in 7 patients, the cancer the lower thorax part-in 7 patients, the cardioesophageal cancer-in 9 patients, a total cancer of a stomach with affection of the bottom third of the oesophagus-in 1 patient. Thoracoscopy and laparoscopy allow determination of the respectability of the tumorous process in the esophageal and stomach cancer considerably lowering the number of exploratory thoracotomies and laparotomies.
基金supported by the National Natural Science Foundation of China(61273357)
文摘In cooperative localization with sparse communication networks, an agent maybe only receives part of locating messages from the others. It is difficult for the receiver to utilize the part instead of global knowledge. Under the extended Kalman filtering, the utilization of the locating message is maximized by two aspects: the locating message generating and multi-locating messages fusing. For the former, the covariance upper-bound technique, by introducing amplification coefficients, is employed to remove the dependency of locating messages on the global knowledge. For the latter, an optimization model is setup; the covariance matrix determinant of the receiver's state estimate, expressed as a function of the amplification coefficients, is selected as the optimization criterion, under linear constraints on the amplification coefficient characteristics and the communication connectivity. Using the optimization solution, the local optimal state of the receiver agent is obtained by the weighting fusion. Simulation with seven agents is shown to evaluate the effectiveness of the proposed algorithm.
基金Sponsored by the Beijing Education Committee Cooperation Building Foundation Project
文摘A new method for speeding up the state augment operations involved in the compressed extended Kalman filter-based simultaneous localization and mapping (CEKF-SLAM) algorithm was proposed. State augment usually requires a fully-updated state eovariance so as to append the information of newly observed landmarks, thus computational volume increases quadratically with the number of landmarks in the whole map. It was proved that state augment can also be achieved by augmenting just one auxiliary coefficient ma- trix. This method can yield identical estimation results as those using EKF-SLAM algorithm, and computa- tional amount grows only linearly with number of increased landmarks in the local map. The efficiency of this quick state augment for CEKF-SLAM algorithm has been validated by a sophisticated simulation project.
基金Supported by Program for Changjiang Scholars and Innovative Research Team in University,National Science Foundation of China(61105092)the National Natural Science Foundation of China(61473042)
文摘In this paper a label-based simultaneous localization and mapping( SLAM) system is proposed to provide localization to indoor autonomous robots. In the system quick response( QR) codes encoded with serial numbers are utilized as labels. These labels are captured by two webcams,then the distances and angles between the labels and webcams are computed. Motion estimated from the two rear wheel encoders is adjusted by observing QR codes. Our system uses the extended Kalman filter( EKF) for the back-end state estimation. The number of deployed labels controls the state estimation dimension. The label-based EKF-SLAM system eliminates complicated processes,such as data association and loop closure detection in traditional feature-based visual SLAM systems. Our experiments include software-simulation and robot-platform test in a real environment. Results demonstrate that the system has the capability of correcting accumulated errors of dead reckoning and therefore has the advantage of superior precision.