Fingerprint authentication system is used to verify users' identification according to the characteristics of their fingerprints.However,this system has some security and privacy problems.For example,some artifici...Fingerprint authentication system is used to verify users' identification according to the characteristics of their fingerprints.However,this system has some security and privacy problems.For example,some artificial fingerprints can trick the fingerprint authentication system and access information using real users' identification.Therefore,a fingerprint liveness detection algorithm needs to be designed to prevent illegal users from accessing privacy information.In this paper,a new software-based liveness detection approach using multi-scale local phase quantity(LPQ) and principal component analysis(PCA) is proposed.The feature vectors of a fingerprint are constructed through multi-scale LPQ.PCA technology is also introduced to reduce the dimensionality of the feature vectors and gain more effective features.Finally,a training model is gained using support vector machine classifier,and the liveness of a fingerprint is detected on the basis of the training model.Experimental results demonstrate that our proposed method can detect the liveness of users' fingerprints and achieve high recognition accuracy.This study also confirms that multi-resolution analysis is a useful method for texture feature extraction during fingerprint liveness detection.展开更多
针对目前基于深度学习的带式输送机煤量检测算法参数量大、难以部署于边缘计算设备及缺乏定量检测的问题,提出一种基于改进DeepLabv3+的带式输送机煤量检测方法。将轻量化网络MobileNetV2作为DeepLabv3+的骨干网络进行特征提取,在尽可...针对目前基于深度学习的带式输送机煤量检测算法参数量大、难以部署于边缘计算设备及缺乏定量检测的问题,提出一种基于改进DeepLabv3+的带式输送机煤量检测方法。将轻量化网络MobileNetV2作为DeepLabv3+的骨干网络进行特征提取,在尽可能保证分割精度的同时提高计算速度;针对煤流与输送带的方向性特征及输送带像素边缘呈现细长条状结构特征,采用条状空洞空间金字塔池化(SASPP)进行加强,并将SASPP模块、1×1卷积与残差结构进行融合,得到CA−SASPP,加强深层次的特征提取;结合CBAM注意力机制实现对特征图中关键信息的加权聚焦。实验结果表明,改进DeepLabv3+模型在平均分割精度仅下降0.36%的情况下,参数量减少了85.58%,推理速度提升至113帧/s,较原方法提高了12帧/s,在保持与原模型相当的分割精度的同时,实现了显著的轻量化效果。基于语义分割结果,通过计算煤量与输送带区域的面积占比,实现了煤量的定量检测,为多级带式输送机的智能调速提供了理论依据。将改进DeepLabv3+模型通过TensorRT加速并部署至Jetson Orin Nano边缘计算设备,实现了煤流图像的实时处理与分析,降低了云端服务器的计算负担,满足了工业现场对实时性和准确性的需求。展开更多
This study proposes a new model of granary storage weight detection based on the Janssen model to satisfy the strategic requirements of granary storage quantity detection in China. The model theoretically elucidates t...This study proposes a new model of granary storage weight detection based on the Janssen model to satisfy the strategic requirements of granary storage quantity detection in China. The model theoretically elucidates the relationship between granary storage weight and bottom/side pressure. A new layout of pressure sensors along the inner and outer rings is also proposed to obtain the pressure value. The experimental results indicate that the detection error of the proposed model is significantly lower than 1% with respect to the low-cost detection system, and this effectively satisfies the actual requirement for real-time monitoring of granary storage quantity.展开更多
Currently, most researches use signals, such as the coil current or voltage of solenoid, to identify parameters; typically, parameter identification method based on variation rate of coil current is applied for positi...Currently, most researches use signals, such as the coil current or voltage of solenoid, to identify parameters; typically, parameter identification method based on variation rate of coil current is applied for position estimation. The problem exists in these researches that the detected signals are prone to interference and difficult to obtain. This paper proposes a new method for detecting the core position by using flux characteristic quantity, which adds a new group of secondary winding to the coil of the ordinary switching electromagnet. On the basis of electromagnetic coupling theory analysis and simulation research of the magnetic field regarding the primary and secondary winding coils, and in accordance with the fact that under PWM control mode varying core position and operating current of windings produce different characteristic of flux increment of the secondary winding. The flux increment of the electromagnet winding can be obtained by conducting time domain integration for the induced voltage signal of the extracted secondary winding, and the core position from the two-dimensional fitting curve of the operating winding current and flux-linkage characteristic quantity of solenoid are calculated. The detecting and testing system of solenoid core position is developed based on the theoretical research. The testing results show that the flux characteristic quantity of switching electromagnet magnetic circuit is able to effectively show the core position and thus to accomplish the non-displacement transducer detection of the said core position of the switching electromagnet. This paper proposes a new method for detecting the core position by using flux characteristic quantity, which provides a new theory and method for switch solenoid to control the proportional valve.展开更多
Optically detected magnetic resonance(ODMR)has emerged as a powerful technique for quantum sensing,enabling high-sensitivity detection of physical quantities even at room temperature.Solid-state defects,such as nitrog...Optically detected magnetic resonance(ODMR)has emerged as a powerful technique for quantum sensing,enabling high-sensitivity detection of physical quantities even at room temperature.Solid-state defects,such as nitrogen-vacancy(NV)centers in diamond,have demonstrated remarkable capabilities in this domain[1–4].However,these systems are limited by their rigid lattice structures and lack tunability.展开更多
基金supported by the NSFC (U1536206,61232016,U1405254,61373133, 61502242)BK20150925the PAPD fund
文摘Fingerprint authentication system is used to verify users' identification according to the characteristics of their fingerprints.However,this system has some security and privacy problems.For example,some artificial fingerprints can trick the fingerprint authentication system and access information using real users' identification.Therefore,a fingerprint liveness detection algorithm needs to be designed to prevent illegal users from accessing privacy information.In this paper,a new software-based liveness detection approach using multi-scale local phase quantity(LPQ) and principal component analysis(PCA) is proposed.The feature vectors of a fingerprint are constructed through multi-scale LPQ.PCA technology is also introduced to reduce the dimensionality of the feature vectors and gain more effective features.Finally,a training model is gained using support vector machine classifier,and the liveness of a fingerprint is detected on the basis of the training model.Experimental results demonstrate that our proposed method can detect the liveness of users' fingerprints and achieve high recognition accuracy.This study also confirms that multi-resolution analysis is a useful method for texture feature extraction during fingerprint liveness detection.
文摘针对目前基于深度学习的带式输送机煤量检测算法参数量大、难以部署于边缘计算设备及缺乏定量检测的问题,提出一种基于改进DeepLabv3+的带式输送机煤量检测方法。将轻量化网络MobileNetV2作为DeepLabv3+的骨干网络进行特征提取,在尽可能保证分割精度的同时提高计算速度;针对煤流与输送带的方向性特征及输送带像素边缘呈现细长条状结构特征,采用条状空洞空间金字塔池化(SASPP)进行加强,并将SASPP模块、1×1卷积与残差结构进行融合,得到CA−SASPP,加强深层次的特征提取;结合CBAM注意力机制实现对特征图中关键信息的加权聚焦。实验结果表明,改进DeepLabv3+模型在平均分割精度仅下降0.36%的情况下,参数量减少了85.58%,推理速度提升至113帧/s,较原方法提高了12帧/s,在保持与原模型相当的分割精度的同时,实现了显著的轻量化效果。基于语义分割结果,通过计算煤量与输送带区域的面积占比,实现了煤量的定量检测,为多级带式输送机的智能调速提供了理论依据。将改进DeepLabv3+模型通过TensorRT加速并部署至Jetson Orin Nano边缘计算设备,实现了煤流图像的实时处理与分析,降低了云端服务器的计算负担,满足了工业现场对实时性和准确性的需求。
基金Supported by Natural Science Project of Henan Provincial Science and Technology Department(172106000013)State Key Laboratory of Grain Information Processing and Control,Ministry of Education(KFJJ-2016-102)Grain Information Processing Technology of University Science and Technology Innovation Team in Henan Province(16IRTSTHN026)
文摘This study proposes a new model of granary storage weight detection based on the Janssen model to satisfy the strategic requirements of granary storage quantity detection in China. The model theoretically elucidates the relationship between granary storage weight and bottom/side pressure. A new layout of pressure sensors along the inner and outer rings is also proposed to obtain the pressure value. The experimental results indicate that the detection error of the proposed model is significantly lower than 1% with respect to the low-cost detection system, and this effectively satisfies the actual requirement for real-time monitoring of granary storage quantity.
基金supported by National Natural Science Foundation of China(Grant No.51175362)
文摘Currently, most researches use signals, such as the coil current or voltage of solenoid, to identify parameters; typically, parameter identification method based on variation rate of coil current is applied for position estimation. The problem exists in these researches that the detected signals are prone to interference and difficult to obtain. This paper proposes a new method for detecting the core position by using flux characteristic quantity, which adds a new group of secondary winding to the coil of the ordinary switching electromagnet. On the basis of electromagnetic coupling theory analysis and simulation research of the magnetic field regarding the primary and secondary winding coils, and in accordance with the fact that under PWM control mode varying core position and operating current of windings produce different characteristic of flux increment of the secondary winding. The flux increment of the electromagnet winding can be obtained by conducting time domain integration for the induced voltage signal of the extracted secondary winding, and the core position from the two-dimensional fitting curve of the operating winding current and flux-linkage characteristic quantity of solenoid are calculated. The detecting and testing system of solenoid core position is developed based on the theoretical research. The testing results show that the flux characteristic quantity of switching electromagnet magnetic circuit is able to effectively show the core position and thus to accomplish the non-displacement transducer detection of the said core position of the switching electromagnet. This paper proposes a new method for detecting the core position by using flux characteristic quantity, which provides a new theory and method for switch solenoid to control the proportional valve.
文摘Optically detected magnetic resonance(ODMR)has emerged as a powerful technique for quantum sensing,enabling high-sensitivity detection of physical quantities even at room temperature.Solid-state defects,such as nitrogen-vacancy(NV)centers in diamond,have demonstrated remarkable capabilities in this domain[1–4].However,these systems are limited by their rigid lattice structures and lack tunability.
