Anomaly IoT Node Detection Based on Local Outlier Factor and Time Series

The heterogeneous nodes in the Internet of Things(IoT)are relatively weak in the computing power and storage capacity.Therefore,traditional algorithms of network security are not suitable for the IoT.Once these nodes alternate between normal behavior and anomaly behavior,it is difficult to identify and isolate them by the network system in a short time,thus the data transmission accuracy and the integrity of the network function will be affected negatively.Based on the characteristics of IoT,a lightweight local outlier factor detection method is used for node detection.In order to further determine whether the nodes are an anomaly or not,the varying behavior of those nodes in terms of time is considered in this research,and a time series method is used to make the system respond to the randomness and selectiveness of anomaly behavior nodes effectively in a short period of time.Simulation results show that the proposed method can improve the accuracy of the data transmitted by the network and achieve better performance.

Image sequence-based risk behavior detection of power operation inspection personnel

A novel image sequence-based risk behavior detection method to achieve high-precision risk behavior detection for power maintenance personnel is proposed in this paper.In this method,the original image sequence data is first separated from the foreground and background.Then,the free anchor frame detection method is used in the foreground image to detect the personnel and correct their direction.Finally,human posture nodes are extracted from each frame of the image sequence,which are then used to identify the abnormal behavior of the human.Simulation experiment results demonstrate that the proposed algorithm has significant advantages in terms of the accuracy of human posture node detection and risk behavior identification.

A preliminary study on photogrammetry for the FAST main reflector measurement

The Five-hundred-meter Aperture Spherical radio Telescope(FAST) is the largest single-dish radio telescope in the world. In this paper, we apply photogrammetry to measure local area surface accuracy of the FAST main reflector. Contrast with the existing photogrammetric methods that need to stick the cooperation target on the panel. In this paper, we directly detect nodes according to their natural feature. Analyzing the FAST reflector composition, we propose a two-step Hough transform method for node detection. Due to the high similarity of the neighboring area around nodes, it is hard to match two images by the feature matching method. Therefore, we apply the nodes combination approach to obtain the homography matrix between two photos for nodes matching. After nodes detection and matching,triangulation and bundle adjustment algorithms are adopted for 3 D reconstruction. During the experiment,the adjusted node position deform a local area of the FAST main reflector into a spherical cap with a radius of 300 m. The experimental result shows that the measurement accuracy of the sphere with a radius of 300 m is 12.299 mm, indicating that it is feasible to apply photogrammetry for the FAST main reflector measurement.

Indocyanine Green Fluorescence Imaging-Guided Lymphangiography in Colorectal Oncologic Practice:Current Use and Future Considerations

The clearance of lesions during surgery for colorectal cancer encompasses the removal of both the primary tumour and its concomitant lymphatic drainage.Huge strides have been made in identifying the precise location of not only the primary tumour,but also the lymph nodes(LNs),owing to the use of intraoperative navigation techniques.Among these techniques,indocyanine green-enhanced fluorescence imaging(ICG-FI)has revolutionized colorectal oncologic surgery by providing clear visualization during lymphangiography.ICG-FI has emerged as a powerful tool for sentinel lymph node procedures that allows for local excision instead of radical D3 lymphadenectomy.It also makes it possible to identify potential metastatic lateral pelvic lymph nodes,which enables simultaneous lymphadenectomy of the pelvic side-wall during the resection of middle-lower rectal cancer.This review provides an update on the current use of and research on ICG-FI-guided LNs mapping for colorectal malignancies,and also discusses its drawbacks and future prospects.