scholarly journals Species-Level Vegetation Mapping in a Himalayan Treeline Ecotone Using Unmanned Aerial System (UAS) Imagery

2018 ◽  
Vol 7 (11) ◽  
pp. 445 ◽  
Author(s):  
Niti Mishra ◽  
Kumar Mainali ◽  
Bharat Shrestha ◽  
Jackson Radenz ◽  
Debendra Karki

Understanding ecological patterns and response to climate change requires unbiased data on species distribution. This can be challenging, especially in biodiverse but extreme environments like the Himalaya. This study presents the results of the first ever application of Unmanned Aerial Systems (UAS) imagery for species-level mapping of vegetation in the Himalaya following a hierarchical Geographic Object Based Image Analysis (GEOBIA) method. The first level of classification separated green vegetated objects from the rest with overall accuracy of 95%. At the second level, seven cover types were identified (including four woody vegetation species). For this, the suitability of various spectral, shape and textural features were tested for classifying them using an ensemble decision tree algorithm. Spectral features alone yielded ~70% accuracy (kappa 0.66) whereas adding textural and shape features marginally improved the accuracy (73%) but at the cost of a substantial increase in processing time. Contrast in plant morphological traits was the key to distinguishing nearby stands as different species. Hence, broad-leaved versus fine needle leaved vegetation were mapped more accurately than structurally similar classes such as Rhododendron anthopogon versus non-photosynthetic vegetation. Results highlight the potential and limitations of the suggested UAS-GEOBIA approach for detailed mapping of plant communities and suggests future research directions.

Drones ◽  
2021 ◽  
Vol 5 (3) ◽  
pp. 81
Author(s):  
Silvano Fortunato Dal Dal Sasso ◽  
Alonso Pizarro ◽  
Salvatore Manfreda

Videos acquired from Unmanned Aerial Systems (UAS) allow for monitoring river systems at high spatial and temporal resolutions providing unprecedented datasets for hydrological and hydraulic applications. The cost-effectiveness of these measurement methods stimulated the diffusion of image-based frameworks and approaches at scientific and operational levels. Moreover, their application in different environmental contexts gives us the opportunity to explore their reliability, potentialities and limitations, and future perspectives and developments. This paper analyses the recent progress on this topic, with a special focus on the main challenges to foster future research studies.


Author(s):  
Richard R. Suminski ◽  
Gregory M. Dominick ◽  
Matthew Saponaro

Evidence suggests that video captured with a wearable video device (WVD) may augment or supplant traditional methods for assessing park use. Unmanned aerial systems (UASs) are used to assess human activity, but research employing them for park assessments is sparse. Therefore, this study compared park user counts between a WVD and UAS. A diverse set of 33 amenities (e.g., playground) in three parks were videoed simultaneously by one researcher wearing a WVD and another operating the UAS. Assessments were done at 12 p.m. and 7 p.m. on weekends, with one park evaluated on two occasions 7 days apart. Two investigators independently reviewed videos and reached consensus on the counts of individuals at each amenity. Intraclass correlation coefficients (ICCs) were used to determine intra- and interrater reliabilities. A total of 404 (M = 4.7; SD = 9.6) and 389 (M = 4.5; SD = 9.0) individuals were counted in the UAS and WVD videos, respectively. Absolute agreement was 86% (74/86) and 100% when no individuals were using the amenity. Whether using all 86 videos or only videos having people (48 videos), ICCs indicated excellent reliability (ICC = .99; p < .001). The totals seen for the repeated measures were UAS = 146 and WVD = 136 for Day 1 and UAS = 169 and WVD = 161 for Day 2. Intrarater reliability was excellent for the UAS (ICC = .92; p < .001) and good for the WVD (ICC = .89; p < .001). Disagreement was mainly due to obstructions—people behind or under structures. This study provides support for the use of UASs for counting park users and future research examining the potential benefits of video analysis for assessing park use.


2021 ◽  
Author(s):  
Michael Parker ◽  
Alex Stott ◽  
Brian Quinn ◽  
Bruce Elder ◽  
Tate Meehan ◽  
...  

Vehicle mobility in cold and challenging terrains is of interest to both the US and Chilean Armies. Mobility in winter conditions is highly vehicle dependent with autonomous vehicles experiencing additional challenges over manned vehicles. They lack the ability to make informed decisions based on what they are “seeing” and instead need to rely on input from sensors on the vehicle, or from Unmanned Aerial Systems (UAS) or satellite data collections. This work focuses on onboard vehicle Controller Area Network (CAN) Bus sensors, driver input sensors, and some externally mounted sensors to assist with terrain identification and overall vehicle mobility. Analysis of winter vehicle/sensor data collected in collaboration with the Chilean Army in Lonquimay, Chile during July and August 2019 will be discussed in this report.


Atmosphere ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 416 ◽  
Author(s):  
Astrid Lampert ◽  
Barbara Altstädter ◽  
Konrad Bärfuss ◽  
Lutz Bretschneider ◽  
Jesper Sandgaard ◽  
...  

Unmanned aerial systems (UAS) fill a gap in high-resolution observations of meteorological parameters on small scales in the atmospheric boundary layer (ABL). Especially in the remote polar areas, there is a strong need for such detailed observations with different research foci. In this study, three systems are presented which have been adapted to the particular needs for operating in harsh polar environments: The fixed-wing aircraft M 2 AV with a mass of 6 kg, the quadrocopter ALICE with a mass of 19 kg, and the fixed-wing aircraft ALADINA with a mass of almost 25 kg. For all three systems, their particular modifications for polar operations are documented, in particular the insulation and heating requirements for low temperatures. Each system has completed meteorological observations under challenging conditions, including take-off and landing on the ice surface, low temperatures (down to −28 ∘ C), icing, and, for the quadrocopter, under the impact of the rotor downwash. The influence on the measured parameters is addressed here in the form of numerical simulations and spectral data analysis. Furthermore, results from several case studies are discussed: With the M 2 AV, low-level flights above leads in Antarctic sea ice were performed to study the impact of areas of open water within ice surfaces on the ABL, and a comparison with simulations was performed. ALICE was used to study the small-scale structure and short-term variability of the ABL during a cruise of RV Polarstern to the 79 ∘ N glacier in Greenland. With ALADINA, aerosol measurements of different size classes were performed in Ny-Ålesund, Svalbard, in highly complex terrain. In particular, very small, freshly formed particles are difficult to monitor and require the active control of temperature inside the instruments. The main aim of the article is to demonstrate the potential of UAS for ABL studies in polar environments, and to provide practical advice for future research activities with similar systems.


Author(s):  
Jiajun Wei ◽  
Matthew L. Bolton ◽  
Laura Humphrey

Psychometrics are increasingly being used to evaluate trust in the automation of safety-critical systems. There is no consensus on what the highest level of measurement is for psychometric trust. This is important as the level of measurement determines what mathematics and statistics can be meaningfully applied to ratings. In this work, we introduce a new method for determining what the maximum level of measurement is for psychometric ratings. We use this to assess the level of measurement of trust in automation using human ratings about the behavior of unmanned aerial systems performing search tasks. Results show that trust is best represented at an ordinal level and that it can be treated as interval in most situations. It is unlikely that trust in automation ratings are ratio. We discuss these results, their implications, and future research.


2020 ◽  
Vol 12 (12) ◽  
pp. 2012 ◽  
Author(s):  
Maja Kucharczyk ◽  
Geoffrey J. Hay ◽  
Salar Ghaffarian ◽  
Chris H. Hugenholtz

Geographic object-based image analysis (GEOBIA) is a remote sensing image analysis paradigm that defines and examines image-objects: groups of neighboring pixels that represent real-world geographic objects. Recent reviews have examined methodological considerations and highlighted how GEOBIA improves upon the 30+ year pixel-based approach, particularly for H-resolution imagery. However, the literature also exposes an opportunity to improve guidance on the application of GEOBIA for novice practitioners. In this paper, we describe the theoretical foundations of GEOBIA and provide a comprehensive overview of the methodological workflow, including: (i) software-specific approaches (open-source and commercial); (ii) best practices informed by research; and (iii) the current status of methodological research. Building on this foundation, we then review recent research on the convergence of GEOBIA with deep convolutional neural networks, which we suggest is a new form of GEOBIA. Specifically, we discuss general integrative approaches and offer recommendations for future research. Overall, this paper describes the past, present, and anticipated future of GEOBIA in a novice-accessible format, while providing innovation and depth to experienced practitioners.


Author(s):  
E. Salami ◽  
J. A. Soler ◽  
R. Cuadrado ◽  
C. Barrado ◽  
E. Pastor

Unmanned aerial systems (UAS, also known as UAV, RPAS or drones) have a great potential to support a wide variety of aerial remote sensing applications. Most UAS work by acquiring data using on-board sensors for later post-processing. Some require the data gathered to be downlinked to the ground in real-time. However, depending on the volume of data and the cost of the communications, this later option is not sustainable in the long term. This paper develops the concept of virtualizing super-computation on-board UAS, as a method to ease the operation by facilitating the downlink of high-level information products instead of raw data. Exploiting recent developments in miniaturized multi-core devices is the way to speed-up on-board computation. This hardware shall satisfy size, power and weight constraints. Several technologies are appearing with promising results for high performance computing on unmanned platforms, such as the 36 cores of the TILE-Gx36 by Tilera (now EZchip) or the 64 cores of the Epiphany-IV by Adapteva. The strategy for virtualizing super-computation on-board includes the benchmarking for hardware selection, the software architecture and the communications aware design. A parallelization strategy is given for the 36-core TILE-Gx36 for a UAS in a fire mission or in similar target-detection applications. The results are obtained for payload image processing algorithms and determine in real-time the data snapshot to gather and transfer to ground according to the needs of the mission, the processing time, and consumed watts.


2019 ◽  
Vol 15 (6) ◽  
pp. 155014771985071 ◽  
Author(s):  
Truong Duy Dinh ◽  
Rustam Pirmagomedov ◽  
Van Dai Pham ◽  
Aram A Ahmed ◽  
Ruslan Kirichek ◽  
...  

The success of the wilderness search and rescue missions is highly dependent on the time required to search for the lost person. The use of unmanned aerial systems may enhance search and rescue missions by supplying aerial support of the search process. There are unmanned aerial system–based solutions, which are capable of detecting the lost person using computer vision, infrared sensors, and detection of a mobile phone signal. The most pressing issue is reducing the cost of a search and rescue mission. Thus, to improve the efficiency of the resource utilization in wilderness search scenario, we consider the use of unmanned aerial system for both mobile phone detection and enabling Wi-Fi communication for the ground portion of the search and rescue team. Such an approach does not require specific additional tools (e.g. access point, specific user equipment) for communication, which reduces the cost and improves the scalability and coordination of the search and rescue mission. As a result, the article provides methods of searching the wilderness for a person using beacon signals from a mobile phone for two situations: when the distance to the source of emergency signals is unknown and when the distance is known. In addition, the voice transmission delay and the number of unmanned aircrafts are found to guaranty the quality of a call.


2021 ◽  
Vol 93 ◽  
pp. 01013
Author(s):  
Artyom Spiridonov

In this article the authors provide an economic assessment of the technology of using unmanned aircraft systems in digital agriculture and justify the optimal requirements for its main technological parameters. As a measure of comparative evaluation of various options for implementing the system, an estimate of the cost of performing the technological process of using pesticides, fertilizers and other agrochemicals in conditional price units is proposed. A multi-factor experiment was carried out and variants of a mathematical model describing the relationship between agrotechnological factors and the final resultant, expressed in the conditional cost of processing 1 Ha of agricultural land, were obtained. The optimal values of the parameters are obtained for various variants of fixing factors at the specified levels. The influence of the most significant agrotechnological factors on the cost of the technological process of using pesticides, fertilizers and other agrochemicals is shown. The values of factors that should be used in the development of new types of unmanned aerial vehicles to ensure their maximum demand in agriculture and economic efficiency are proposed.


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