GEOMATIC TECHNIQUES FOR THE OPTIMIZATION OF SKI RESOURCES

Abstract. Climate change is already affecting the entire world, with extreme weather conditions such as drought, heat waves, heavy rain, floods and landslides becoming more frequent, including Europe. In according to Paris agreement and relative European announcement of Carbon neutrality (by 2050), the saving of water and energy supplies is a fundamental aspect in the management of resources in production, sports, hospitality facilities and so on. Some methodologies for the optimization of the consumption of natural resources are required. This article describes an activity aimed at measuring, monitoring and analysing the thickness of the snowpack on the ski slopes during the winter season to permit a sustainable approach of snowmaking in alpine ski areas . The authors propose a methodology based on the integration of multitemporal surface (ground/snow) survey by Autonomous Aerial Vehicle (AAV) and low cost GNSS receivers mounted on snow groomers for a RTK (Real Time Kinematic) solution. To obtain a complete snow surface digital models with poor detailed images on ski slopes, some pre-processing techniques have been analysed to locally improve contrast and details with a local high pass filtering. The methodology has been employed in two study areas (Limone Piemonte, Prato Nevoso) located in the province of Cuneo, in the southern alpine area of Piedmont.

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Detection of water vapor time variations associated with heavy rain in northern Italy by geodetic and low-cost GNSS receivers

Earth Planets and Space ◽

10.1186/s40623-018-0795-7 ◽

2018 ◽

Vol 70 (1) ◽

Cited By ~ 22

Author(s):

Stefano Barindelli ◽

Eugenio Realini ◽

Giovanna Venuti ◽

Alessandro Fermi ◽

Andrea Gatti

Keyword(s):

Water Vapor ◽

Low Cost ◽

Heavy Rain ◽

Northern Italy ◽

Gnss Receivers ◽

Time Variations

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A REDUNDANT GNSS-INS LOW-COST UAV NAVIGATION SOLUTION FOR PROFESSIONAL APPLICATIONS

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprsarchives-xl-3-w3-299-2015 ◽

2015 ◽

Vol XL-3/W3 ◽

pp. 299-306

Author(s):

J. Navarro ◽

M. E. Parés ◽

I. Colomina ◽

G. Bianchi ◽

S. Pluchino ◽

...

Keyword(s):

Precision Agriculture ◽

Low Cost ◽

Research Work ◽

Close Coupling ◽

Coupling Techniques ◽

Gnss Receivers ◽

Processing Techniques ◽

Long Baselines ◽

Uav Navigation ◽

Positive Results

This paper presents the current results for the FP7 GINSEC project. Its goal is to build a pre-commercial prototype of a low-cost, accurate and reliable system for the professional UAV market. Low-cost, in this context, stands for the use of sensors in the most affordable segment of the market, especially MEMS IMUs and GNSS receivers. Reliability applies to the ability of the autopilot to cope with situations where unfavourable GNSS reception conditions or strong electromagnetic fields make the computation of the position and / or attitude of the UAV difficult. Professional and accurate mean that, at least using post-processing techniques as PPP, it will be possible to reach cm-level precisions that open the door to a range of applications demanding high levels of quality in positioning, as precision agriculture or mapping. To achieve such goal, a rigorous sensor error modelling approach, the use of redundant IMUs and a dual-GNSS receiver setup, together with close-coupling techniques and an extended Kalman filter with self-analysis capabilities have been used. Although the project is not yet complete, the results obtained up to now prove the feasibility of the aforementioned goal, especially in those aspects related to position determination. Research work is still undergoing to estimate the heading using a dual-GNNS receiver setup; preliminary results prove the validity of this approach for relatively long baselines, although positive results are expected when these are shorter than 1 m – which is a necessary requisite for small-sized UAVs.

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Reducing multipath effect of low-cost GNSS receivers for monitoring by considering temporal correlations

Journal of Applied Geodesy ◽

10.1515/jag-2019-0059 ◽

2020 ◽

Vol 14 (2) ◽

pp. 167-175

Author(s):

Li Zhang ◽

Volker Schwieger

Keyword(s):

Low Cost ◽

Ground Plane ◽

Single Frequency ◽

Spatial Correlations ◽

Raw Data ◽

Multipath Effect ◽

Temporal Correlations ◽

Multipath Effects ◽

Gnss Receivers ◽

Multipath Signals

AbstractThe investigations on low-cost single frequency GNSS receivers at the Institute of Engineering Geodesy (IIGS) show that u-blox GNSS receivers combined with low-cost antennas and self-constructed L1-optimized choke rings can reach an accuracy which almost meets the requirements of geodetic applications (see Zhang and Schwieger [25]). However, the quality (accuracy and reliability) of low-cost GNSS receiver data should still be improved, particularly in environments with obstructions. The multipath effects are a major error source for the short baselines. The ground plate or the choke ring ground plane can reduce the multipath signals from the horizontal reflector (e. g. ground). However, the shieldings cannot reduce the multipath signals from the vertical reflectors (e. g. walls).Because multipath effects are spatially and temporally correlated, an algorithm is developed for reducing the multipath effect by considering the spatial correlations of the adjoined stations (see Zhang and Schwieger [24]). In this paper, an algorithm based on the temporal correlations will be introduced. The developed algorithm is based on the periodic behavior of the estimated coordinates and not on carrier phase raw data, which is easy to use. Because, for the users, coordinates are more accessible than the raw data. The multipath effect can cause periodic oscillations but the periods change over time. Besides this, the multipath effect’s influence on the coordinates is a mixture of different multipath signals from different satellites and different reflectors. These two properties will be used to reduce the multipath effect. The algorithm runs in two steps and iteratively. Test measurements were carried out in a multipath intensive environment; the accuracies of the measurements are improved by about 50 % and the results can be delivered in near-real-time (in ca. 30 minutes), therefore the algorithm is suitable for structural health monitoring applications.

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A Novel Electrically Small Ground-Penetrating Radar Patch Antenna with a Parasitic Ring for Respiration Detection

Sensors ◽

10.3390/s21061930 ◽

2021 ◽

Vol 21 (6) ◽

pp. 1930

Author(s):

Di Shi ◽

Taimur Aftab ◽

Gunnar Gidion ◽

Fatma Sayed ◽

Leonhard M. Reindl

Keyword(s):

Ground Penetrating Radar ◽

Patch Antenna ◽

Low Cost ◽

Substrate Material ◽

Geometric Parameters ◽

Gas Explosions ◽

Aerial Vehicle ◽

Electromagnetic Characteristics ◽

Ground Penetrating ◽

Quick Search

An electrically small patch antenna with a low-cost high-permittivity ceramic substrate material for use in a ground-penetrating radar is proposed in this work. The antenna is based on a commercial ceramic 915 MHz patch antenna with a size of 25 × 25 × 4 mm3 and a weight of 12.9 g. The influences of the main geometric parameters on the antenna’s electromagnetic characteristics were comprehensively studied. Three bandwidth improvement techniques were sequentially applied to optimize the antenna: tuning the key geometric parameters, adding cuts on the edges, and adding parasitic radiators. The designed antenna operates at around 1.3 GHz and has more than 40 MHz continuous −3 dB bandwidth. In comparison to the original antenna, the −3 and −6 dB fractional bandwidth is improved by 1.8 times and 4 times, respectively. Two antennas of the proposed design together with a customized radar were installed on an unmanned aerial vehicle (UAV) for a quick search for survivors after earthquakes or gas explosions without exposing the rescue staff to the uncertain dangers of moving on the debris.

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UAV-Driven Structural Crack Detection and Location Determination Using Convolutional Neural Networks

Sensors ◽

10.3390/s21082650 ◽

2021 ◽

Vol 21 (8) ◽

pp. 2650

Author(s):

Daegyun Choi ◽

William Bell ◽

Donghoon Kim ◽

Jichul Kim

Keyword(s):

Visual Information ◽

Crack Detection ◽

Image Data ◽

Image Processing Techniques ◽

Location Determination ◽

Aerial Vehicle ◽

Using Data ◽

Processing Techniques ◽

Deep Learning Model ◽

Structural Cracks

Structural cracks are a vital feature in evaluating the health of aging structures. Inspectors regularly monitor structures’ health using visual information because early detection of cracks on highly trafficked structures is critical for maintaining the public’s safety. In this work, a framework for detecting cracks along with their locations is proposed. Image data provided by an unmanned aerial vehicle (UAV) is stitched using image processing techniques to overcome limitations in the resolution of cameras. This stitched image is analyzed to identify cracks using a deep learning model that makes judgements regarding the presence of cracks in the image. Moreover, cracks’ locations are determined using data from UAV sensors. To validate the system, cracks forming on an actual building are captured by a UAV, and these images are analyzed to detect and locate cracks. The proposed framework is proven as an effective way to detect cracks and to represent the cracks’ locations.

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Multi-Blockchain-Based IoT Data Processing Techniques to Ensure the Integrity of IoT Data in AIoT Edge Computing Environments

Sensors ◽

10.3390/s21103515 ◽

2021 ◽

Vol 21 (10) ◽

pp. 3515

Author(s):

Sung-Ho Sim ◽

Yoon-Su Jeong

Keyword(s):

Low Cost ◽

Third Party ◽

Monitoring And Control ◽

Constant Size ◽

Computing Environments ◽

Iot Devices ◽

Cloud Servers ◽

The Cost ◽

Processing Techniques ◽

And Control

As the development of IoT technologies has progressed rapidly recently, most IoT data are focused on monitoring and control to process IoT data, but the cost of collecting and linking various IoT data increases, requiring the ability to proactively integrate and analyze collected IoT data so that cloud servers (data centers) can process smartly. In this paper, we propose a blockchain-based IoT big data integrity verification technique to ensure the safety of the Third Party Auditor (TPA), which has a role in auditing the integrity of AIoT data. The proposed technique aims to minimize IoT information loss by multiple blockchain groupings of information and signature keys from IoT devices. The proposed technique allows IoT information to be effectively guaranteed the integrity of AIoT data by linking hash values designated as arbitrary, constant-size blocks with previous blocks in hierarchical chains. The proposed technique performs synchronization using location information between the central server and IoT devices to manage the cost of the integrity of IoT information at low cost. In order to easily control a large number of locations of IoT devices, we perform cross-distributed and blockchain linkage processing under constant rules to improve the load and throughput generated by IoT devices.

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Robustness against Chirp Signal Interference of On-Board Vehicle Geodetic and Low-Cost GNSS Receivers

Sensors ◽

10.3390/s21165257 ◽

2021 ◽

Vol 21 (16) ◽

pp. 5257

Author(s):

Franc Dimc ◽

Polona Pavlovčič-Prešeren ◽

Matej Bažec

Keyword(s):

Interference Mitigation ◽

Low Cost ◽

Density Ratio ◽

Autonomous Driving ◽

Signal Interference ◽

Noise Power ◽

Reference Base ◽

Noise Power Spectral Density ◽

Processing Abilities ◽

Gnss Receivers

Robust autonomous driving, as long as it relies on satellite-based positioning, requires carrier-phase-based algorithms, among other types of data sources, to obtain precise and true positions, which is also primarily true for the use of GNSS geodetic receivers, but also increasingly true for mass-market devices. The experiment was conducted under line-of-sight conditions on a straight road during a period of no traffic. The receivers were positioned on the roof of a car travelling at low speed in the presence of a static jammer, while kinematic relative positioning was performed with the static reference base receiver. Interference mitigation techniques in the GNSS receivers used, which were unknown to the authors, were compared using (a) the observed carrier-to-noise power spectral density ratio as an indication of the receivers’ ability to improve signal quality, and (b) the post-processed position solutions based on RINEX-formatted data. The observed carrier-to-noise density generally exerts the expected dependencies and leaves space for comparisons of applied processing abilities in the receivers, while conclusions on the output data results comparison are limited due to the non-synchronized clocks of the receivers. According to our current and previous results, none of the GNSS receivers used in the experiments employs an effective type of complete mitigation technique adapted to the chirp jammer.

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Turning Base Transceiver Stations into Scalable and Controllable DC Microgrids Based on a Smart Sensing Strategy

Sensors ◽

10.3390/s21041202 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1202

Author(s):

Miguel Tradacete ◽

Carlos Santos ◽

José A. Jiménez ◽

Fco Javier Rodríguez ◽

Pedro Martín ◽

...

Keyword(s):

Electricity Market ◽

Low Cost ◽

Storage System ◽

Environmental Parameters ◽

Weather Conditions ◽

Energy Storage System ◽

Electricity Grid ◽

Dc Microgrids ◽

Smart Sensing ◽

Battery Energy

This paper describes a practical approach to the transformation of Base Transceiver Stations (BTSs) into scalable and controllable DC Microgrids in which an energy management system (EMS) is developed to maximize the economic benefit. The EMS strategy focuses on efficiently managing a Battery Energy Storage System (BESS) along with photovoltaic (PV) energy generation, and non-critical load-shedding. The EMS collects data such as real-time energy consumption and generation, and environmental parameters such as temperature, wind speed and irradiance, using a smart sensing strategy whereby measurements can be recorded and computing can be performed both locally and in the cloud. Within the Spanish electricity market and applying a two-tariff pricing, annual savings per installed battery power of 16.8 euros/kW are achieved. The system has the advantage that it can be applied to both new and existing installations, providing a two-way connection to the electricity grid, PV generation, smart measurement systems and the necessary management software. All these functions are integrated in a flexible and low cost HW/SW architecture. Finally, the whole system is validated through real tests carried out on a pilot plant and under different weather conditions.

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