Обнаружение транспортных средств на изображениях загородных шоссе на основе метода Single shot multibox Detector

This paper reviews recent progress of portable short-range noncontact microwave radar systems for motion detection, positioning, and imaging applications. With the continuous advancements of modern semiconductor technologies and embedded computing, many functionalities that could only be achieved by bulky radar systems in the past are now integrated into portable devices with integrated circuit chips and printed circuits boards. These portable solutions are able to provide high motion detection sensitivity, excellent signal-to-noise ratio, and satisfactory range detection capability. Assisted by on-board signal processing algorithms, they can play important roles in various areas, such as health and elderly care, veterinary monitoring, human-computer interaction, structural monitoring, indoor tracking, and wind engineering. This paper reviews some system architectures and practical implementations for typical wireless sensing applications. It also discusses potential future developments for the next-generation portable smart radar systems.

A Review on Recent Progress of Portable Short-Range Noncontact Microwave Radar Systems

This paper presents the results of a research project aimed at examining the capabilities and challenges of two distinct but not mutually exclusive approaches to in-service bridge assessment: visual inspection and installed monitoring systems. In this study, the intended functionality of both approaches was evaluated on its ability to identify potential structural damage and to provide decision-making support. Inspection and monitoring are compared in terms of their functional performance, cost, and barriers (real and perceived) to implementation. Both methods have strengths and weaknesses across the metrics analyzed, and it is likely that a hybrid evaluation technique that adopts both approaches will optimize efficiency of condition assessment and ultimately lead to better decision making.

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Comparison of Visual Inspection and Structural-Health Monitoring As Bridge Condition Assessment Methods

Short-range noncontact sensors are capable of remotely detecting the precise movements of the subjects or wirelessly estimating the distance from the sensor to the subject. They find wide applications in our day lives such as noncontact vital sign detection of heart beat and respiration, sleep monitoring, occupancy sensing, and gesture sensing. In recent years, short-range noncontact sensors are attracting more and more efforts from both academia and industry due to their vast applications. Compared to other radar architectures such as pulse radar and frequency-modulated continuous-wave (FMCW) radar, Doppler radar is gaining more popularity in terms of system integration and low-power operation. This paper reviews the recent technical advances in Doppler radars for healthcare applications, including system hardware improvement, digital signal processing, and chip integration. This paper also discusses the hybrid FMCW-interferometry radars and the emerging applications and the future trends.

https://www.mdpi.com/1424-8220/16/8/1169/pdf

Short-Range Noncontact Sensors for Healthcare and Other Emerging Applications: A Review.

Owing to effective and flexible data acquisition, unmanned aerial vehicle (UAV) has recently become a hotspot across the fields of computer vision (CV) and remote sensing (RS). Inspired by recent success of deep learning (DL), many advanced object detection and tracking approaches have been widely applied to various UAV-related tasks, such as environmental monitoring, precision agriculture, traffic management. This paper provides a comprehensive survey on the research progress and prospects of DL-based UAV object detection and tracking methods. More specifically, we first outline the challenges, statistics of existing methods, and provide solutions from the perspectives of DL-based models in three research topics: object detection from the image, object detection from the video, and object tracking from the video. Open datasets related to UAV-dominated object detection and tracking are exhausted, and four benchmark datasets are employed for performance evaluation using some state-of-the-art methods. Finally, prospects and considerations for the future work are discussed and summarized. It is expected that this survey can facilitate those researchers who come from remote sensing field with an overview of DL-based UAV object detection and tracking methods, along with some thoughts on their further developments.

Deep Learning for UAV-based Object Detection and Tracking: A Survey

Object detection in high-resolution aerial images is a challenging task because of 1) the large variation in object size, and 2) non-uniform distribution of objects A common solution is to divide the large aerial image into small (uniform) crops and then apply object detection on each small crop In this paper, we investigate the image cropping strategy to address these challenges Specifically, we propose a Density-Map guided object detection Network (DMNet), which is inspired from the observation that the object density map of an image presents how objects distribute in terms of the pixel intensity of the map As pixel intensity varies, it is able to tell whether a region has objects or not, which in turn provides guidance for cropping images statistically DMNet has three key components: a density map generation module, an image cropping module and an object detector DMNet generates a density map and learns scale information based on density intensities to form cropping regions Extensive experiments show that DMNet achieves state-of-the-art performance on two popular aerial image datasets, ie VisionDrone [30] and UAVDT [4]

/pdf/density-map-guided-object-detection-in-aerial-images-1wwc3j6ptx.pdf

Density Map Guided Object Detection in Aerial Images

This paper introduces a strategy for automatically selecting dc offset calibration methods on a 24-GHz continuous wave (CW) radar sensor, which measures displacement for the purpose of structural health monitoring Obtaining accurate displacement measurements using CW radar requires the successful application of dc offset calibration This article compares four commonly applied dc offset calibration methods with a focus on each of the methods' accuracy and efficiency for different measurement signal characteristics Simulation results are presented to evaluate the accuracy of each method An advanced systematic strategy for selecting the most appropriate method based on signal characteristics is developed The automated selection strategy is implemented in software and validated on experimental data

Automated DC Offset Calibration Strategy for Structural Health Monitoring Based on Portable CW Radar Sensor

Summary
Continuous wave (CW) radar sensors are a promising technology for structural displacement measurement. However, the commonly employed passive backscattering measurement configuration has some limitations for low-power applications of CW radar. To improve displacement measurement performance using the low-power CW radar, an active transponder configuration is introduced. Compared with passive backscattering, the active transponder configuration is capable of increasing the radar's signal power, thereby increasing the signal to noise ratio for more accurate displacement measurement. A series of laboratory experiments to demonstrate the performance of the transponder configuration was conducted, and the experimental results were compared with the results of using the backscattering configuration. The investigation revealed that the signal improvement provided by the transponder is a function of the distance between the transponder and the radar. In addition, a full-scale bridge test with the active transponder configuration was conducted to verify the improved performance. An oblique angle test using the transponder was conducted in the laboratory to demonstrate the potential for flexible installation strategies when deploying the radar/transponder pair for bridge displacement measurements. Copyright © 2016 John Wiley & Sons, Ltd.

Structural displacement measurements using DC coupled radar with active transponder

Smart Radar Sensor Network for Bridge Displacement Monitoring

The development of effective structural health monitoring (SHM) strategies is critical as aging infrastructure remains a
national concern with widespread impact on the quality of our daily lives. Wireless smart sensor networks (WSSNs) are
an attractive alternative to traditional SHM systems for their lower deployment cost and their ability to enable new
methods of distributed data processing. While acceleration has been the primary measurement utilized in most WSSN
SHM applications, practically and accurately capturing structural deflections has been proven much more challenging.
Displacement sensors produce reliable low-frequency measurements but are often difficult to implement in long-term
field deployments. Conventional technologies for measuring deflection, both dynamic and static, are either too bulky or
expensive to be integrated into WSSNs or lack sufficient accuracy. This paper presents the validation and
characterization of a network of low-cost, wireless radar-based sensors for the enhancement of low-frequency vibrationbased
bridge monitoring and the measurement of static bridge deflections. Experimental results utilizing a laboratoryscale
truss bridge are presented and the performance of the wireless radar sensors is compared to conventional vibration
and displacement transducers. In addition, challenges associated with detection distance, interference rejection and
signal processing are discussed.

Shanyue Guan

Papers

Density Map Guided Object Detection in Aerial Images

Automated DC Offset Calibration Strategy for Structural Health Monitoring Based on Portable CW Radar Sensor

Structural displacement measurements using DC coupled radar with active transponder

Smart Radar Sensor Network for Bridge Displacement Monitoring

A radar-based sensor network for bridge displacement measurements