scholarly journals Ablation Patterns of the Debris Covered Tongue of Halong Glacier Revealed by Short Term Unmanned Aerial Vehicle Surveys

2021 ◽  
Vol 9 ◽  
Author(s):  
Wanqin Guo ◽  
Xiaojun Guo ◽  
Yushuo Liu ◽  
Jing Li ◽  
Donghui Shangguan ◽  
...  
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Limited Area ◽  
Short Term ◽  
Exponential Relationship ◽  
Glacier Tongue ◽  
Mass Losses ◽  
Surface Models ◽  
Aerial Vehicle ◽  
Negative Exponential

Debris-covered glaciers are an important glacier type and have attracted more and more attention. This study presents the results of ablation patterns of debris-covered tongue of the Halong Glacier in the northeastern Tibetan Plateau, by using two repeated unmanned aerial vehicle (UAV) surveys performed on August 11 and September 15, 2019. The results show that the tongue of Halong Glacier has experienced strong ablation during the surveyed period, with an overall ice loss amount to 4.17 × 105 metric tons Among all the briefly classified surface types, supraglacial debris has the largest area (80.9%) and also mass losses (58.6%) comparing to others. However, ice cliffs show the strongest and the most significant ablation rates (averagely 1.36 and 1.22 m w.e. for supraglacial and lateral ice cliffs, respectively), followed by clean ice regions (1.01 m w.e.). The backwastes of ice cliffs also resulted in up to 7.8 m horizontal back-off at different parts of Halong Glacier, lead to fast terminal retreat and narrowing down of the glacier tongue, and may result in the break off of Halong Glacier tongue into separated parts in the future. The surface ablation rates show a clear negative exponential relationship with the measured debris thicknesses, well in accordance with previous studies. Regions in cutting and flushing by supraglacial and lateral rivers have the largest surface elevation decreases but are not significant due to their limited area and the relatively lower quality of UAV digital surface models (DSMs) in those covered regions.

scholarly journals Active stabilization of unmanned aerial vehicle imaging platform

2020 ◽  
Vol 26 (19-20) ◽  
pp. 1791-1803 ◽  
Author(s):  
Mohit Verma ◽  
Vicente Lafarga ◽  
Mael Baron ◽  
Christophe Collette
Keyword(s):  
Unmanned Aerial Vehicles ◽  
Unmanned Aerial Vehicle ◽  
Vibration Isolation ◽  
Isolation System ◽  
Aerial Vehicles ◽  
Active Stabilization ◽  
Aerial Vehicle ◽  
Active Vibration ◽  
Improved Performance

The advancement in technology has seen a rapid increase in the use of unmanned aerial vehicles for various applications. These unmanned aerial vehicles are often equipped with the imaging platform like a camera. During the unmanned aerial vehicle flight, the camera is subjected to vibrations which hamper the quality of the captured images/videos. The high-frequency vibrations from the unmanned aerial vehicle are transmitted to the camera. Conventionally, passive rubber mounts are used to isolate the camera from the drone vibrations. The passive mounts are able to provide reduction in response near the resonance. However, this comes at the cost of amplification of response at the higher frequency. This article proposes an active vibration isolation system which exhibits improved performance at the higher frequencies than the conventional system. The active isolation system consists of a contact-less voice coil actuator supported by four springs. Experiments are carried out to study the effect of vibrations on the quality of images captured. The characterization of drone vibrations is also carried out by recording the acceleration during different flight modes. The performance of the proposed isolation system is experimentally validated on a real drone camera subjected to the recorded drone acceleration spectrum. The isolation system is found to perform better than the conventional rubber mounts and is able to reduce the vibrations to a factor of one-fourth. It can be effectively used to improve the image acquisition quality of the unmanned aerial vehicles.

scholarly journals Utilization of Unmanned Aerial Vehicle, Artificial Intelligence, and Remote Measurement Technology for Bridge Inspections

2020 ◽  
Vol 32 (6) ◽  
pp. 1244-1258
Author(s):  
Pang-jo Chun ◽  
Ji Dang ◽  
Shunsuke Hamasaki ◽  
Ryosuke Yajima ◽  
Toshihiro Kameda ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
Unmanned Aerial Vehicle ◽  
Measurement Technology ◽  
Remote Measurement ◽  
Bridge Inspection ◽  
Current State ◽  
Bridge Collapse ◽  
Bridge Inspections ◽  
Aerial Vehicle

In recent years, aging of bridges has become a growing concern, and the danger of bridge collapse is increasing. To appropriately maintain bridges, it is necessary to perform inspections to accurately understand their current state. Until now, bridge inspections have involved a visual inspection in which inspection personnel come close to the bridges to perform inspection and hammering tests to investigate abnormal noises by hammering the bridges with an inspection hammer. Meanwhile, as there are a large number of bridges (for example, 730,000 bridges in Japan), and many of these are constructed at elevated spots; the issue is that the visual inspections are laborious and require huge cost. Another issue is the wide disparity in the quality of visual inspections due to the experience, knowledge, and competence of inspectors. Accordingly, the authors are trying to resolve or ameliorate these issues using unmanned aerial vehicle (UAV) technology, artificial intelligence (AI) technology, and telecommunications technology. This is discussed first in this paper. Next, the authors discuss the future prospects of bridge inspection using robot technology such as a 3-D model of bridges. The goal of this paper is to show the areas in which deployment of the UAV, robots, telecommunications, and AI is beneficial and the requirements of these technologies.

USING A CONSUMER-GRADE UNMANNED AERIAL VEHICLE TO MEASURE SHORT-TERM GEOMORPHOLOGICAL CHANGES IN DYNAMIC COASTAL SETTINGS

2019 ◽  
Author(s):  
Gary Sundin ◽  
◽  
Katherine Luciano ◽  
Tanner Arrington ◽  
Benjamin Stone ◽  
...  
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Short Term ◽  
Aerial Vehicle ◽  
Geomorphological Changes

CALCULATION OF THE AERODYNAMIC CHARACTERISTICS OF A UAV TAKING INTO ACCOUNT THE INSTALLED ELEMENTS OF ANTI-ICE SYSTEM IN A VIRTUAL ENVIRONMENT XFLR5

2019 ◽  
Vol 12 (2) ◽  
pp. 66-71
Author(s):  
А. Мельников ◽  
A. Mel'nikov
Keyword(s):  
Virtual Environment ◽  
Unmanned Aerial Vehicle ◽  
Aerodynamic Characteristics ◽  
Wing Profile ◽  
Aerial Vehicle ◽  
Aerodynamic Quality

Based on the geometric dimensions of the CLARK-Y wing profile used in the design of various aircraft models, the calculations of its main aerodynamic characteristics were carried out. Taking into account the developed method of protecting the wing of an unmanned aerial vehicle (UAV) from icing, changes were made to the profile structure taking into account the installation features of the anti-icing system (AIS) elements. Both profiles are digitally entered into the XFLR5 program, where the aerodynamic quality of the wing was calculated before installing the AIS elements and with the elements installed. Wing polarities were obtained, on the basis of which conclusions were drawn about the possibility of using the developed AIS.

MONITORING OF TRAFFIC USING UNMANNED AERIAL VEHICLE IN MALAYSIA LANDSCAPE PERSPECTIVE

2015 ◽  
Vol 76 (1) ◽  
Author(s):  
Azizul Abdullah ◽  
Elmi Abu Bakar ◽  
Muhammad Zaim Mohamed Pauzi
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Ground Control ◽  
Limited Area ◽  
Traffic Flows ◽  
Highway Traffic ◽  
Traffic Condition ◽  
Starting Point ◽  
Ground Control Station ◽  
Aerial Vehicle ◽  
On The Road

Collecting information on traffic flows are important for provide high quality road system. At present, fixed camera is widely used for the monitoring system which covers limited area.  Therefore, the unmanned aerial vehicle (UAV) such as quadrotor is developed for monitoring traffic flow since the UAV is responsive mobile sensing system. This development of UAV platform is a starting point for developed a highway traffic and management system which is in future can be enhance by connected the system with graphical user interface (GUI) on ground control station that can defined types of vehicles and analyze level of congestion. At present, the system that developed only transmits a real time video to ground control station without any interpretation by software that detects types of vehicles and analyzes traffic condition. Through the surveillance and monitoring of traffic flows that done at Engineering Campus, Universiti Sains Malaysia, the system provides suitable information for authorities to analyse level of congestion happened on the road and provide alternative solution for users in order to avoid the traffic jam.  

scholarly journals Unmanned Aerial Vehicle Surveying For Monitoring Road Construction Earthworks

2019 ◽  
Vol 14 (1) ◽  
pp. 1-17 ◽  
Author(s):  
Kalev Julge ◽  
Artu Ellmann ◽  
Romet Köök
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Road Construction ◽  
Point Clouds ◽  
Satellite System ◽  
Ground Control Points ◽  
Surface Models ◽  
Aerial Vehicle ◽  
Global Navigation Satellite ◽  
Sand And Gravel ◽  
The Impact

Unmanned aerial vehicle photogrammetry is a surveying technique that enables generating point clouds, 3D surface models and orthophoto mosaics. These are based on photos captured with a camera placed on an unmanned aerial vehicle. Within the framework of this research, unmanned aerial vehicle photogrammetry surveys were carried out over a sand and gravel embankment with the aim of assessing the vertical accuracy of the derived surface models. Flight altitudes, ground control points and cameras were varied, and the impact of various factors on the results was monitored. In addition, the traditional real-time-kinematic Global Navigation Satellite System surveys were conducted for verifications. Surface models acquired by different methods were used to calculate volumes and compare the results with requirements set by Estonian Road Administration. It was found that with proper measuring techniques an accuracy of 5.7 cm for the heights were achieved.

scholarly journals Experimental inspection of the dosing-sowing device by unmanned aerial vehicle for the resettlement of trichogrammes

2019 ◽  
pp. 61-71
Author(s):  
Maranda, S.
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Statistical Data ◽  
Experimental Studies ◽  
Material Distribution ◽  
Flight Altitude ◽  
Operating Modes ◽  
Aerial Vehicle ◽  
Biological Protection ◽  
The Right

Purpose. Improving the quality of the trichograms' resettlement by establishing rational operating modes of the dosing and sowing device of an unmanned aerial vehicle. Methods. Experimental studies using the method of planning a three-factor experiment, methods of statistical data processing. Results. Based on the analysis of the technical means for resettlement of the trichograms, the design of the dosing-sowing device of a unmanned aerial vehicle for the resettlement of the trichogram was substantiated. As a result of the experimental studies, it was established that during the deployment of a trichogram with a dosing-seeding device, a stable leakage of the material due to ejection was ensured by using diaphragms with a diameter of 2.5 mm or more. According to the results of the research it was established that with the increase in flight altitude, the quality of material distribution does not change significantly. But factors such as the height of the plants and the presence of obstacles on the field must be taken into account, so it is necessary to keep the flight altitude not less than 5 m. Due to changing the size of the confuser, the range of flight of the particle did not change, which leads to the conclusion to use a smaller cone of diameter due to which reduces the frontal resistance. When using a dosing-seeding device for resettlement of a trichogram on a quadracycle, due to air flow from propellers, the width of the capture significantly decreases. Therefore, for the qualitative distribution of biomaterials on the surface of the field, the distance between adjacent passages should be 6 m. Conclusions 1. The height of the flight of an unmanned aerial vehicle during the resettlement of the trichogram must not be less 5 m from the upper edge of the plant. 2. The uniform distribution of material on the surface of the field depends on the flight speed, which should be within the range of 3–5 m/s. 3. The quality of the material distribution increases from the right choice of the width of the ceiling, which should be about 6 m. Conclusions: dosing sowing device, ejector, unmanned aerial vehicle, biological protection of plants, reshaping of trichograms, norm of settlement, width of capture.

scholarly journals Kualitas Struktur Tanah di Setiap Bentuklahan di DAS Kaliwungu

2020 ◽  
Vol 33 (2) ◽  
Author(s):  
Adhera Sukmawijaya ◽  
Junun Sartohadi
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Soil Profile ◽  
Soil Structure ◽  
Soil Layer ◽  
Soil Management ◽  
Visual Evaluation ◽  
Structure Quality ◽  
Sustainable Soil Management ◽  
Aerial Vehicle

Pengelolaan tanah untuk pertanian yang berkelanjutan perlu untuk memeperhatikan 2 hal, yaitu bentuklahan dan tanah. Faktor tanah yang perlu diperhatikan adalah struktur tanah. Penelitian yang fokus pada bentuklahan, struktur tanah, dan implikasinya pada pengelolan belum pernah dilakukan di DAS Kaliwungu. Penelitian bertujuan untuk menganalisis struktur tanah pada setiap bentuklahan sebagai dasar untuk pengelolaan tanah yang berkelanjutan. Kualitas struktur tanah ditentukan dari observasi profil tanah pada setiap bentuklahan. Identifikasi bentuklahan dilakukan berdasarkan pengumpulan data dari Kendaraan Nirawak. Viusal Evaluation of Subsoil Strucutre (SubVESS) digunakan untuk menentukan kualitas struktur tanah berdasarkan karakteristik struktur tanah. Hasil menunjukkan bahwa area penelitian memiliki kualitas struktur tanah yang baik dengan mayoritas nilai kualitas strutktur tanah yang berkisan antara Ssq 1-3. Tidak diperlukan adanya perubahan dalam pengelolaan tanah pada area kajian.Soil management for sustainable agriculture needs to focus on 2 things, which are landform and soil. Soil factor that needs to be focused on is soil structure. The study that focused on landform, soil structure and its implication on soil management has never been done in Kaliwungu Watershed. This research aims to analyze soil structure on every landform as the basis to determine sustainable soil management. Soil structure quality was determine by soil profile observation on every landform. Unmanned Aerial Vehicle (UAV) photographic data was used to identify each landform. Visual Evaluation of Subsoil Structure (SubVESS) was used to identify the quality of soil structure based on its characteristic. The result shows that study area has a good soil structure quality with the majority of soil layer has a good soil structure quality (Ssq 1-3). There is no need to change in soil management is needed.

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