892 research outputs found
Book of abstracts of the 24th Euro Working Group on Transportation Meeting
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Advanced Sensors for Real-Time Monitoring Applications
It is impossible to imagine the modern world without sensors, or without real-time information about almost everything—from local temperature to material composition and health parameters. We sense, measure, and process data and act accordingly all the time. In fact, real-time monitoring and information is key to a successful business, an assistant in life-saving decisions that healthcare professionals make, and a tool in research that could revolutionize the future. To ensure that sensors address the rapidly developing needs of various areas of our lives and activities, scientists, researchers, manufacturers, and end-users have established an efficient dialogue so that the newest technological achievements in all aspects of real-time sensing can be implemented for the benefit of the wider community. This book documents some of the results of such a dialogue and reports on advances in sensors and sensor systems for existing and emerging real-time monitoring applications
A New Form of Interlocking Developing Technology for Level Crossings and Depots with International Applications
There are multiple large rail infrastructure projects planned or currently being undertaken within the
United Kingdom. Many of these projects aim to reduce the continual issue of limited or overcapacity
service. These projects involve an expansion of Rail lines, introducing faster lines, improved stations in
towns and cities and better communication networks. Some major projects like Control Period 6 (CP6) are
being managed by Network Rail; where projects are initiated throughout Great Britain. Many projects are
managed outside Great Britain e.g., Trans-European Transport Network Program, which is planning for
expansion of Rail lines (almost double) for High-Speed Rails (category I and II). These projects will increase
the number of junctions and Level Crossings. A Level Crossing is where a Rail Line is crossed by a road or
a walkway without the use of a tunnel or bridge. The misuse from the road users account for nearly 90%
of the fatalities and near misses at Level Crossings. During 2016/2017, the Rail Network recorded 6
fatalities, about 400 near-misses and more than 77 incidents of shock and trauma. Accidents at Level
Crossings represent 8% of the total accidents from the whole Rail Network. Office of Rail and Road (ORR)
suggested that among these accidents at Level Crossings 90% of them are pedestrians. Such high numbers
of accidents, fatalities and high risk have alarmed authorities. These authorities found it necessary to
invest time and utilise given resources to improve the safety system at a Level Crossing using the safer
and reliable interlocking system. The interlocking system is a feature of a control system that makes the
state of two functions mutually independent. The primary function of Interlocking is to ensure that trains
are safe from collision and derailment. Considering the risk associated with the Level Crossing system, the
new proposed interlocking system should utilise the sensing system available at a Level Crossing to
significantly reduce implementation cost and comply with the given standards and Risk Assessments. The
new proposed interlocking system is designed to meet the “Safety Integrity Level- SIL” and possibly use
the “2oo2” approach for its application at a Level Crossing, where the operational cycle is automated or
train driver is alarmed for risk situations. Importantly, the new proposed system should detect and classify
small objects and provide a reasonable solution to the current risk associated with Level Crossing, which
was impossible with the traditional sensing systems.
The present work discusses the sensors and algorithms used and has the potential to detect and classify
objects within a Level Crossing area. The review of existing solutions e.g Inductive Loops and other major
sensors allows the reader to understand why RADAR and Video Cameras are preferable choices of a
sensing system for a Level Crossing. Video data provides sufficient information for the proposed algorithm
to detect and classify objects at Level Crossings without the need of a manual “operator”. The RADAR
sensing system can provide information using micro-Doppler signatures, which are generated from small
regular movements of an obstacle. The two sensors will make the system a two-layer resilient system. The
processed information from these two sensing systems is used as the “2oo2” logic system for Interlocking
for automating the operational cycle or alarm the train drive using effective communication e.g., GSM-R.
These two sensors provide sufficient information for the proposed algorithm, which will allow the system
to automatically make an “intelligent decision” and proceed with a safe Level Crossing operational cycle.
Many existing traditional algorithms depend on pixels values, which are compared with background pixels.
This approach cannot detect complex textures, adapt to a dynamic background or avoid detection of
unnecessary harmless objects. To avoid these problems, the proposed work utilises “Deep Learning”
technology integrated with the proposed Vision and RADAR system. The Deep Learning technology can
learn representations from labelled pixels; hence it does not depend on background pixels. The Deep
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Learning technology can classify, detect and localise objects at a Level Crossing area. It can classify and
differentiate between a child and a small inanimate object, which was impossible with traditional
algorithms. The system can detect an object regardless of its position, orientation and scale without any
additional training because it learns representation from the data and does not rely on background pixels.
The proposed system e.g., Deep Learning technology is integrated with the existing Vision System and
RADAR installed at a Level Crossing, hence implementation cost is significantly reduced as well.
The proposed work address two main aspects of training a model using Deep Learning technology; training
from scratch and training using Transfer Learning techniques. Results are demonstrated for Image
Classification, Object Detection and micro-Doppler signals from RADAR. An architecture of Convolutional
Neural Network from scratch is trained consisting of Input Layer, Convolution, Pooling and Dropout Layer.
The model achieves an accuracy of about 66.78%. Different notable models are trained using Transfer
Learning techniques and their results are mentioned along with the MobileNet model, which achieves the
highest accuracy of 91.9%. The difference between Image Classification and Object Detection is discussed
and results for Object Detection are mentioned as well, where the Loss metrics are used to evaluate the
performance of the Object Detector. MobileNet achieves the smallest loss metric of about 0.092. These
results clearly show the effectiveness and preferability of these models for their applicability at Level
Crossings. Another Convolutional Neural Network is trained using micro-Doppler signatures from the
Radar system. The model trained using the micro-Doppler signature achieved an accuracy of 92%.
The present work also addresses the Risk Assessment associated with the installation and maintenance
of the system using Deep Learning technology. RAMS (Reliability, Availability, Maintainability and Safety)
management system is used to address the General and Specific Risks associated with the sensing system
integrated with the Deep Learning technology. Finally, the work is concluded with the preferred choice,
its application, results and associated Risk Assessment. Deep Learning is an evolving field with new
improvements being introduced constantly. Any new challenges and problems should be monitored
regularly. Some future work is discussed as well. To further improve the model's accuracy, the dataset
from the same distribution should be gathered with the cooperation of relevant Railway authorities. Also,
the RADAR dataset could be generated rather than simulated to further include diversity and avoid any
biases in the dataset during the training process. Also, the proposed system can be implemented and used
in different applications within the Rail Industry e.g., passenger census and classification of passengers at
the platform as discussed in the work
Advances in Sensors and Sensing for Technical Condition Assessment and NDT
The adequate assessment of key apparatus conditions is a hot topic in all branches of industry. Various online and offline diagnostic methods are widely applied to provide early detections of any abnormality in exploitation. Furthermore, different sensors may also be applied to capture selected physical quantities that may be used to indicate the type of potential fault. The essential steps of the signal analysis regarding the technical condition assessment process may be listed as: signal measurement (using relevant sensors), processing, modelling, and classification. In the Special Issue entitled “Advances in Sensors and Sensing for Technical Condition Assessment and NDT”, we present the latest research in various areas of technology
Intelligent Transportation Related Complex Systems and Sensors
Building around innovative services related to different modes of transport and traffic management, intelligent transport systems (ITS) are being widely adopted worldwide to improve the efficiency and safety of the transportation system. They enable users to be better informed and make safer, more coordinated, and smarter decisions on the use of transport networks. Current ITSs are complex systems, made up of several components/sub-systems characterized by time-dependent interactions among themselves. Some examples of these transportation-related complex systems include: road traffic sensors, autonomous/automated cars, smart cities, smart sensors, virtual sensors, traffic control systems, smart roads, logistics systems, smart mobility systems, and many others that are emerging from niche areas. The efficient operation of these complex systems requires: i) efficient solutions to the issues of sensors/actuators used to capture and control the physical parameters of these systems, as well as the quality of data collected from these systems; ii) tackling complexities using simulations and analytical modelling techniques; and iii) applying optimization techniques to improve the performance of these systems. It includes twenty-four papers, which cover scientific concepts, frameworks, architectures and various other ideas on analytics, trends and applications of transportation-related data
The probability of detecting and tracking RADAR targets in clutter at low grazing angles
Modern military acquisition and tracking RADARs are required to operate
against aircraft and missiles specifically designed to have minimal
radar cross section (RCS) and which fly at very low level to take
maximum advantage of terrain screening.
A model for predicting system performance is necessary for a range of
terrain types in varying precipitation and seasonal cultural conditions.
While the main degradation is from surface clutter and denial of sightline
due to terrain and other local obstructions, several other factors such
as multipath propagation, deliberate jamming and even operator performance
contribute to the total model. The possibility that some radars may
track obscured targets, however briefly, by using the diffraction path,
is of particular interest.
Although this report critically examines each of the contributory factors
in order to select optimum values for inclusion in an overall computer
prediction model; a new surface clutter model is specifically developed
for sloped terrain using actual clutter measurements. The model is
validated by comparison with an extensive survey of worldwide clutter
results from both published and unpublished sources.
Certain constraints have been necessary to restrict the study to a
manageable size, while meeting the requirements of the sponsors.
Attention is therefore focussed upon performance prediction for
typical mobile tracking radar systems designed for operation against
small RCS low level targets flying overland
Urban Deformation Monitoring using Persistent Scatterer Interferometry and SAR tomography
This book focuses on remote sensing for urban deformation monitoring. In particular, it highlights how deformation monitoring in urban areas can be carried out using Persistent Scatterer Interferometry (PSI) and Synthetic Aperture Radar (SAR) Tomography (TomoSAR). Several contributions show the capabilities of Interferometric SAR (InSAR) and PSI techniques for urban deformation monitoring. Some of them show the advantages of TomoSAR in un-mixing multiple scatterers for urban mapping and monitoring. This book is dedicated to the technical and scientific community interested in urban applications. It is useful for choosing the appropriate technique and gaining an assessment of the expected performance. The book will also be useful to researchers, as it provides information on the state-of-the-art and new trends in this fiel
Infrastructure Design, Signalling and Security in Railway
Railway transportation has become one of the main technological advances of our society. Since the first railway used to carry coal from a mine in Shropshire (England, 1600), a lot of efforts have been made to improve this transportation concept. One of its milestones was the invention and development of the steam locomotive, but commercial rail travels became practical two hundred years later. From these first attempts, railway infrastructures, signalling and security have evolved and become more complex than those performed in its earlier stages. This book will provide readers a comprehensive technical guide, covering these topics and presenting a brief overview of selected railway systems in the world. The objective of the book is to serve as a valuable reference for students, educators, scientists, faculty members, researchers, and engineers
Advancements in Measuring and Modeling the Mechanical and Hydrological Properties of Snow and Firn: Multi-sensor Analysis, Integration, and Algorithm Development
Estimating snow mechanical properties – such as elastic modulus, stiffness, and strength – is important for understanding how effectively a vehicle can travel over snow-covered terrain. Vehicle instrumentation data and observations of the snowpack are valuable for improving the estimates of winter vehicle performance. Combining in-situ and remotely-sensed snow observations, driver input, and vehicle performance sensors requires several techniques of data integration. I explored correlations between measurements spanning from millimeter to meter scales, beginning with the SnowMicroPenetrometer (SMP) and instruments applied to snow that were designed for measuring the load bearing capacity and the compressive and shear strengths of roads and soils. The spatial distribution of snow’s mechanical properties is still largely unknown. From this initial work, I determined that snow density remains a useful proxy for snowpack strength. To measure snow density, I applied multi-sensor electromagnetic methods. Using spatially distributed snowpack, terrain, and vegetation information developed in the subsequent chapters, I developed an over-snow vehicle performance model. To measure the vehicle performance, I joined driver and vehicle data in the coined Normalized Difference Mobility Index (NDMI). Then, I applied regression methods to distribute NDMI from spatial snow, terrain, and vegetation properties. Mobility prediction is useful for the strategic advancement of warfighting in cold regions.
The security of water resources is climatologically inequitable and water stress causes international conflict. Water resources derived from snow are essential for modern societies in climates where snow is the predominant source of precipitation, such as the western United States. Snow water equivalent (SWE) is a critical parameter for yearly water supply forecasting and can be calculated by multiplying the snow depth by the snow density. In this work, I combined high-spatial resolution light detection and ranging (LiDAR) measured snow depths with ground-penetrating radar (GPR) measurements of two-way travel-time (TWT) to solve for snow density. Then using LiDAR derived terrain and vegetation features as predictors in a multiple linear regression, the density observations are distributed across the SnowEx 2020 study area at Grand Mesa, Colorado. The modeled density resolved detailed patterns that agree with the known interactions of snow with wind, terrain, and vegetation. The integration of radar and LiDAR sensors shows promise as a technique for estimating SWE across entire river basins and evaluating observational- or physics-based snow-density models. Accurate estimation of SWE is a means of water security.
In our changing climate, snow and ice mass are being permanently lost from the cryosphere. Mass balance is an indicator of the (in)stability of glaciers and ice sheets. Surface mass balance (SMB) may be estimated by multiplying the thickness of any annual snowpack layer by its density. Though, unlike applications in seasonal snowpack, the ages of annual firn layers are unknown. To estimate SMB, I modeled the firn depth, density, and age using empirical and numerical approaches. The annual SMB history shows cyclical patterns representing the combination of atmospheric, oceanic, and anthropogenic climate forcing, which may serve as evaluation or assimilation data in climate model retrievals of SMB.
The advancements made using the SMP, multi-channel GPR arrays, and airborne LiDAR and radar within this dissertation have made it possible to spatially estimate the snow depth, density, and water equivalent in seasonal snow, glaciers, and ice sheets. Open access, process automation, repeatability, and accuracy were key design parameters of the analyses and algorithms developed within this work. The many different campaigns, objectives, and outcomes composing this research documented the successes and limitations of multi-sensor estimation techniques for a broad range of cryosphere applications
ESSE 2017. Proceedings of the International Conference on Environmental Science and Sustainable Energy
Environmental science is an interdisciplinary academic field that integrates physical-, biological-, and information sciences to study and solve environmental problems. ESSE - The International Conference on Environmental Science and Sustainable Energy provides a platform for experts, professionals, and researchers to share updated information and stimulate the communication with each other. In 2017 it was held in Suzhou, China June 23-25, 2017
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