Eddies assume a pivotal role in both the oceanic heat cycle and marine dynamic processes. The development of real-time satellite observations, coupled with advancements in computer intelligence, has propelled automati...
详细信息
Eddies assume a pivotal role in both the oceanic heat cycle and marine dynamic processes. The development of real-time satellite observations, coupled with advancements in computer intelligence, has propelled automatic eddy detection algorithms to the forefront of ocean remote sensing research. Nevertheless, target omissions and accuracy degradations are inevitable for multiple detection algorithms due to strong morphological variations in ocean eddies. This paper proposes an automatic detection algorithm based on the quadrant angle of the velocity vector in the flow field. Firstly, a rectangular search box is established, and the corresponding quadrant angles at the four vertices are calculated. Secondly, the centres and types of eddies are determined according to the cumulative sum and variety rules of quadrant angles. Then the outermost boundary is identified by regularity of quadrant angles in eight directions expanding outward from the centre of the eddy using the stream function equation. The new algorithm is assessed and verified using geostrophic flow data derived from the CMEMS standard gridded sea level anomaly product. Furthermore, its detection capabilities are demonstrated through a comparative analysis with several other algorithms. All methods exhibit consistent efficacy in detecting the majority of eddies with similar spatial distributions. In cases where the new algorithm identifies a specific eddy not detected by the FF15 and ND10 algorithms, sea surface temperature data is employed for verification. The sea surface temperature distribution map, along with the obtained results, illustrates the superiority of the new algorithm and its adaptability to products with varying resolutions. Additionally, the results undergo verification through a manual detection method, revealing that the new algorithm achieves SDR of 91.73% and an EDR of 3.54%. This percentage significantly surpasses the lower acceptable limit of 80% for the SDR parameter. The new algor
An objects detection algorithm for color dynamic images from two cameras is proposed for a surveillance system under low illumination. It provides automatic calculation of a fuzzy corresponding map and color similarit...
详细信息
An objects detection algorithm for color dynamic images from two cameras is proposed for a surveillance system under low illumination. It provides automatic calculation of a fuzzy corresponding map and color similarity for lower luminance conditions, which detects little chromatic regions in CCD camera images under lower illumination and presents regions with a possibility of occlusion situation. Experimental detection results for two dynamic images from real surveillance cameras in a downtown area in Japan under low luminance conditions show that the proposed algorithm has 15% improved accuracy compared with the independent detection algorithm in the same false alarm rate, which occlusion regions are correctly presented. Moreover, implementability for severe surveillance situation is discussed. The proposed algorithm is being considered for use in a low cost surveillance system at a relatively poor security downtown (shopping mall) area in Japan. (C) 2007 Elsevier B.V. All rights reserved.
In this paper, the new detection algorithm of scene boundary based on information theory has been presented. It uses the changed color of frame image as feature. With the detection of scene sudden change and gradual c...
详细信息
ISBN:
(纸本)9780769536880
In this paper, the new detection algorithm of scene boundary based on information theory has been presented. It uses the changed color of frame image as feature. With the detection of scene sudden change and gradual change, this algorithm can get better experiment results compared with others.
A point target detection algorithm for IR image is proposed based on spatial statistics. Firstly, according to the spatial correlation of atmosphere background in infrared image, the spatial statistical analysis metho...
详细信息
ISBN:
(纸本)9780819497765
A point target detection algorithm for IR image is proposed based on spatial statistics. Firstly, according to the spatial correlation of atmosphere background in infrared image, the spatial statistical analysis method is adopted, and a background suppression algorithm based on Kriging is put forward. Secondly, using peak detection algorithm merged with Kriging, the problem of high false-alarm probability for adaptive threshold filter is solved by dual channel filter. The result shows that the detection probability of the algorithm reaches to 99 percent when the input SCR is no less than 6 and probability of false alarm is between 1x10(-3) and 1x10(-4).
As a hot-spot of 5G, the research on detection algorithms for massive multiple input multiple output (MIMO) system is significant but difficult. The traditional MIMO detection algorithms or their improvements are not ...
详细信息
As a hot-spot of 5G, the research on detection algorithms for massive multiple input multiple output (MIMO) system is significant but difficult. The traditional MIMO detection algorithms or their improvements are not appropriate for large scaled antennas. In this paper, we propose artificial bee colony (ABC) detection algorithm for massive MIMO system. As one advanced technology of swarm intelligence, ABC algorithm is most efficient for large scaled constrained numerical combinatorial optimization problem. Therefore, we employ it to search the optimum solution vector in the modulation alphabet with linear detection result as initial. Simulation and data analysis prove the correctness and efficiency. Versus the scale of massive MIMO systems from 64 x 64 to 1024 x 1024 with uncoded four-quadrature-amplitude-modulation signals, the proposed ABC detection algorithm obtains bit error rate of 10(-5) at low average received signal-to-noise-ratio of 12 dB with rapid convergence rate, which approximates the optimum bit error rate performance of the maximum likelihood and achieves the theoretical optimum spectral efficiency with low required average received signal-to-noise-ratio of 10 dB in similar increasing regularity, over finite time of low polynomial computational complexity of O(N-T(2)) per symbol, where N-T denotes the transmitting antennas' number. The proposed ABC detection algorithm is efficient for massive MIMO system. Copyright (C) 2016 John Wiley & Sons, Ltd.
In order to obtain the best scheme of safety production and operation decision-making of a smart factory and improve the rapid response ability of product information of a smart factory, the safety production detectio...
详细信息
In order to obtain the best scheme of safety production and operation decision-making of a smart factory and improve the rapid response ability of product information of a smart factory, the safety production detection algorithm of a smart factory is designed by using programmable computer (PC) control technology. The main interface, login interface, function interface, and navigation interface are designed, respectively, to realize the front-end design of the smart factory safety production detection platform. Based on PC control technology, the hardware equipment of perception layer, network layer, and application layer are installed, and on this basis, the database of the smart factory safety production detection platform is established. Once the operation data information is collected and detected, it is stored to the equipment fault experience knowledge base, and the fault diagnosis method of the minimum cut set of the fault tree is used to implement the on-site equipment diagnosis of the underlying Internet of Things of the smart factory, and finally the information sharing function of safety production detection through the information transmission of the safety production links of each smart factory is realized. Experiments show that the throughput data of the designed algorithm run stably, improve the control accuracy of safety production, and effectively improve the work efficiency.
Recommender system is widely used in various fields for dealing with information overload effectively, and collaborative filtering plays a vital role in the system. However, recommender system suffers from its vulnera...
详细信息
Recommender system is widely used in various fields for dealing with information overload effectively, and collaborative filtering plays a vital role in the system. However, recommender system suffers from its vulnerabilities by malicious attacks significantly, especially, shilling attacks because of the open nature of recommender system and the dependence on data. Therefore, detecting shilling attack has become an important issue to ensure the security of recommender system. Most of the existing methods of detecting shilling attack are based on user ratings, and one limitation is that they are likely to be interfered by obfuscation techniques. Moreover, traditional detection algorithms cannot handle different types of shilling attacks flexibly. In order to solve the problems, we proposed an outlier degree shilling attack detection algorithm by using dynamic feature selection. Considering the differences when users choose items, we combined rating-based indicators with user popularity, and utilized the information entropy to select detection indicators dynamically. Therefore, a variety of shilling attack models can be dealt with flexibility in this way. The experiments show that the proposed algorithm can achieve better detection performance and interference immunity.
In the traditional physical layer encryption methods, both the delay and errors brought by the keys generation and interaction and those from the channel estimation are too high to be employed for the uplink multiuser...
详细信息
In the traditional physical layer encryption methods, both the delay and errors brought by the keys generation and interaction and those from the channel estimation are too high to be employed for the uplink multiuser massive multiple-input and multiple-output (MIMO) systems. Differently, this paper constructs a lightweight encryption scheme with the modulation random chaotic encryption (MRCE) signals in the uplink massive MIMO systems where the keys are not required to be known, a priori, at the base station (BS). Their generation is off-line and does not employ the channel state information, and there is no immediate interaction. Specially, as a deep learning based solution for detecting the MRCE signals in the uplink massive MIMO systems, the convolutional-neural-network aided nonlinear detection (CAD) algorithms are proposed in this paper. The simulation results showed their effectiveness. The anti-eavesdrop ability of the MRCE signals is verified even against eavesdroppers equipped with multiple antennas at high average signal to noise ratio (SNR). As shown in the simulation results, when the BS does not previously know the keys, the proposed CAD algorithms have a much better bit error rate (BER) performance and higher secrecy spectral efficiency (SSE) than the less efficient ones of their corresponding unassisted methods. The BER is closer to the theoretical lower bound of the optimum value obtained by the maximum likelihood method. They require lower average received SNR to converge to the theoretical maximum SSE given by the no error transmissions from the legitimate users to the BS. These performances also approach those of their corresponding unassisted algorithms without prior known keys. The proposed CAD algorithms have medium/strong robustness against the channel estimation error and medium/low polynomial computational complexity.
The application of autonomous driving technology in the field of transportation has become a hot research direction, and autonomous vehicles need to accurately detect and track moving targets around. As a kind of sens...
详细信息
The application of autonomous driving technology in the field of transportation has become a hot research direction, and autonomous vehicles need to accurately detect and track moving targets around. As a kind of sensor widely used in the field of automatic driving, LiDAR has the characteristics of high precision and long distance detection. Therefore, this paper adopts a target detection algorithm based on three-dimensional LiDAR, which can identify moving targets accurately. Then the motion path of the detected target is captured and tracked by optical method, and the motion state of the target is monitored in real time. The experimental results show that the moving target detection algorithm and optical motion acquisition method based on 3D LiDAR can detect and track the moving target effectively, and capture its moving trajectory accurately. The application of this method to autonomous vehicles can improve vehicle perception and driving safety, and also provide a useful reference for other fields of moving object detection and tracking research.
Aiming at the problems of parameter optimization and insufficient utilization of split reads in the detection for copy number variation (CNV), a new definition of relative read depth (RRD) and a randomized sampling st...
详细信息
Aiming at the problems of parameter optimization and insufficient utilization of split reads in the detection for copy number variation (CNV), a new definition of relative read depth (RRD) and a randomized sampling strategy (RGN) are proposed in this paper. Compared to the raw read depth, the RRD parameter has weak correlation with GC content, mappability and the width of analysis windows tiled along the genome. The RGN strategy is based on the weighted sampling strategy which can speed up the read count data analysis. Subsequently, we propose an improved detection algorithm for CNV based on hidden Markov model (CNV-HMM). The HMM detects the abnormal signal of read count data and outputs the detection results of candidate CNVs. At the end of the algorithm, we filter out the results of candidate CNVs using the split reads to improve the performance of CNV-HMM algorithm. Finally, the experiment results show that our CNV-HMM algorithm has higher sensitivity and accuracy for CNVs detection than most of current detection algorithms and applicative both for diploid animal and plant.
暂无评论