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Abstrakt

The objective of this paper is to estimate performance of a new approach for spectrum sharing and coordination between terrestrial base stations (BS) and On-board radio access nodes (UxNB) carried by Unmanned Aerial Vehicles (UAV). This approach employs an artificial intelligence (AI) based algorithm implemented in a centralized controller. According to the assessment based on the latest specifications of 3rd Generation Partnership Project (3GPP) the newly defined Unmanned Aerial System Traffic Management (UTM) is feasible to implement and utilize an algorithm for dynamic and efficient distribution of available radio resources between all radio nodes involved in process of optimization. An example of proprietary algorithm has been described, which is based on the principles of Kohonen neural networks. The algorithm has been used in simulation scenario to illustrate the performance of the novel approach of centralized radio channels allocation between terrestrial BSs and UxNBs deployed in 3GPP-defined rural macro (RMa) environment. Simulation results indicate that at least 85% of simulated downlink (DL) transmissions are gaining additional channel bandwidth if presented algorithm is used for spectrum distribution between terrestrial BSs and UxNBs instead of baseline soft frequency re-use (SFR) approach.
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Bibliografia

[1] 3GPP, “UAS-UAV”, https://www.3gpp.org/uas-uav, accessed 18 November 2019.
[2] 3GPP TR 36.777, “Release 15. Enhanced LTE support for aerial vehicles”, January 2018.
[3] 3GPP TS 22.125, “Release 16. Unmanned Aerial System (UAS) support in 3GPP. Stage 1”, September 2019.
[4] 3GPP TS 22.125, “Release 17. Unmanned Aerial System (UAS) support in 3GPP. Stage 1”, December 2019.
[5] S. Zhang, Y. Zeng, R. Zhang, “Cellular-Enabled UAV Communication: A Connectivity-Constrained Trajectory Optimization Perspective”, IEEE Transactions on Communications, Vol. 67, No. 3, March 2019. DOI: 10.1109/TCOMM.2018.2880468.
[6] B. Li, Z. Fei, Y. Zhang, “UAV Communications for 5G and Beyond: Recent Advances and Future Trends”, IEEE Internet of Things Journal, Vol. 6, No. 2, April 2019. DOI: 10.1109/JIOT.2018.2887086.
[7] L. Sboui, H. Ghazzai, Z. Rezki, M.-S. Alouini, “Energy-Efficient Power Allocation for UAV Cognitive Radio Systems”, 2017 IEEE 86th Vehicular Technology Conference (VTC-Fall). DOI: 10.1109/VTCFall.2017.8287971.
[8] J. Huang, W. Mei, J. Xu, Q. Ling, Z. Rui, “Cognitive UAV Communication via Joint Maneuver and Power Control”, IEEE Transactions on Communications, Vol. 67, No. 11, November 2019. DOI: 10.1109/TCOMM.2019.2931322.
[9] G. Hattab, D. Cabric, “Energy-Efficient Massive IoT Shared Spectrum Access over UAV-enabled Cellular Networks”, Accepted for publication in IEEE Transactions on Communications, 2020. DOI: 10.1109/TCOMM.2020.2998547.
[10] C. Zhang, W. Zhang, “Spectrum Sharing for Drone Networks”, IEEE Journal on Selected Areas in Communications, Vol. 35, No. 1, January 2017. DOI: 10.1109/JSAC.2016.2633040.
[11] X. Ying, M.M. Buddhikot, S. Roy, “SAS-Assisted Coexistence-Aware Dynamic Channel Assignment in CBRS Band”, IEEE Transactions on Wireless Communications, Vol. 17, No. 9, September 2018. DOI: 10.1109/TWC.2018.2858261.
[12] T. Kohonen, “Self-Organizing Maps”, Series in Information Sciences, Vol. 30, Springer-Verlag Berlin Heidelberg, Third ed., 2001.
[13] K. Bechta, “Radio resource allocation”, International Application No.: PCT/FI2017/050149.
[14] Y. Yu, E. Dutkiewicz, X. Huang, M. Mueck, G. Fang, “Performance Analysis of Soft Frequency Reuse for Inter-cell Interference Coordination in LTE Networks”, 2010 10th International Symposium on Communications and Information Technologies. DOI: 10.1109/ISCIT.2010.5665044.
[15] 3GPP TS 38.901, “Release 16. Study on channel model for frequencies from 0.5 to 100 GHz”, January 2020.

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Autorzy i Afiliacje

Kamil Bechta
1

  1. Mobile Networks Business Division of Nokia

Abstrakt

The Land and Property Register (LPR) also called the Cadastre by the legislator should function in accordance with regulations in force, meet expectations of the public and provide universal access to Register data for its users. Beyond any doubt, credibility and usefulness of data in this public register are affected by the manner it is kept, which generally in-cludes active and passive approach. If the LPR is kept in an active manner and constantly up to date, its data is very useful. The qualitative aspect of the land and buildings database’s records establishes the calculation accuracy of the owners’ land parcels evidenced in the Land and Mortgage Registers, which protect the ownership right to the property. In order to ensure that the plot of land is unequivocally and correctly measured, it is necessary to establish breakpoints of the parcels’ bounda-ries in the presence of the interested parties.

Research conducted on the possibility of using the unmanned aerial vehicle (UAV) for measuring purposes indicates immense probability where this technology may be used for the selected details of group I (most accurately located) in modernization of land and buildings registers.

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Autorzy i Afiliacje

Karol Ożóg

Abstrakt

One of the little described problems in hydrostatic drives is the fast changing runs in the hydraulic line of this drive affecting the nature of the formation and intensity of pressure pulsation and flow rate occurring in the drive. Pressure pulsation and flow rate are the cause of unstable operation of servos, delays in the control system and other harmful phenomena. The article presents a flow model in a hydrostatic drive line based on fluid continuity equations (mass conservation), maintaining the amount of Navier-Stokes motion in the direction of flow (x axis), energy conservation (liquid state). The movement of liquids in a hydrostatic line is described by partial differential equations of the hyperbolic type, so modeling takes into account the wave phenomena occurring in the line. The hydrostatic line was treated as a cross with two inputs and two outputs, characterized by a specific transmittance matrix. The product approximation was used to solve the wave equations. An example of the use of general equations is presented for the analysis of a miniaturized hydrostatic drive line fed from a constant pressure source and terminated by a servo mechanism.

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Autorzy i Afiliacje

L. Ułanowicz
G. Jastrzębski

Abstrakt

The investigation of a decentralized radio network dedicated to unmanned aerial systems (UASs) was presented in the paper. Two frequencies (315 MHz; 434 MHz) and five different configurations of Gaussian frequency-shift keying (GFSK) were taken into account. Three different algorithms for decentralized networks were investigated and their influence on the network capacity was measured. The research was done both for static and dynamically changed unmanned aerial vehicle (UAV) positions. In order to quantify the research three different parameters were determined: RSSI, nP (number of data packets in one second), and f (frequency of data update).
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Autorzy i Afiliacje

Patryk Szywalski
1
Andrzej Waindok
1
ORCID: ORCID

  1. Faculty of Electrical Engineering, Automatic Control and Informatics, Department of Electrical Engineering and Mechatronics,Opole University of Technology, Opole, Poland

Abstrakt

The aim of this research is to evaluate the performance of four UAV image processing software for the automatic estimation of volumes based on estimated volume accuracy, spatial accuracy, and execution time, with and without Ground Control Points (GCPs). A total of 52 images of a building were captured using a DJI Mavic Air UAV at 60m altitude and 80% forward and side overlap. The dataset was processed with and without GCPs using Pix4DMapper, Agisoft Metashape Pro, Reality Capture, and 3DF Zephyr. The UAV-based estimated volume generated from the software was compared with the true volume of the building generated from its as-built 3D building information modeled in Revit 2018 environment. The resulting percentage difference was computed. The average volumes estimated from the four software with the use of GCPs were 4757.448 m3 (3.87%), 4728.1 m3 (2.54%), 4291.561 m3 (11.5%), and 4154.938 m3 (14.35%), respectively. Similarly, when GCPs were not used for the image processing, average volumes of 4631.385 m3 (4.52%), 4773.025 m3 (1.6%), 4617.899 m3 (4.89%), and 4420.403 m3 (8.92%) were obtained in the same order. In addition to the volume estimation analysis, other parameters, including execution time, positional RMSE, and spatial resolution, were evaluated. Based on these parameters, Agisoft Metashape Pro proved to be more accurate, time-efficient, and reliable for volumetric estimations from UAV images compared to the other investigated software. The findings of this study can guide decision-making in selecting the appropriate software for UAV-based volume estimation in different applications.
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Autorzy i Afiliacje

Oluibukun Gbenga Ajayi
1 2
ORCID: ORCID
Bolaji Saheed Ogundele
2
ORCID: ORCID
Gideon Abidemi Aleji
2
ORCID: ORCID

  1. Namibia University of Science and Technology, Windhoek, Namibia
  2. Federal University of Technology, Minna, Nigeria

Abstrakt

The use of unmanned aerial vehicles (UAVs) is booming in almost every sector of the economy, especially in the agricultural industry. According to some reports, the agricultural UAV market is expected to increase from USD 2.6 billion in 2020 to USD 9.5 billion in 2030. In this paper a brief overview devoted to the use of UAVs in the Russian State Agrarian University – Moscow Timiryazev Agricultural Academy (RSAU-MTAA), including the results of studying the equipment use effectiveness for automatic driving of tractor equipment when sowing grain crops and planting potatoes. In the course of studying the equipment use effectiveness for automatic driving of tractor equipment, the deviations of the guess row spacing from the standard row spacing provided for by the seeder design were established; in the case of sowing barley using a marker, it was up to 4.3 cm, and in the case of winter wheat it was up to 5 cm. When using the autopilot system, these values were no more than 1.5 and 2.3 cm, respectively, which indicates the high accuracy and efficiency of the automatic driving systems. The autopilot system use provided a deviation of adjacent rows from the straightness when planting potatoes from 2.8 to 3.0 cm. The paper concludes that the use of unmanned robotic systems in agriculture, in conjunction with modern means of receiving and processing information, opens up new opportunities for increasing agriculture efficiency.
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Autorzy i Afiliacje

Victor I. Balabanov
1
ORCID: ORCID
Dmitriy M. Benin
2
ORCID: ORCID
Natalya A. Mochunova
2
ORCID: ORCID

  1. Federal State Budgetary Educational Institution of Higher Education “Russian State Agrarian University – Moscow Timiryazev Agricultural Academy”, Reclamation and Construction Machines Department, Timiryazevskaya street, 49, Moscow, 127550, Russia
  2. Federal State Budgetary Educational Institution of Higher Education “Russian State Agrarian University – Moscow Timiryazev Agricultural Academy”, A.N. Kostyakov Institute of Land Reclamation, Water Management and Construction, Moscow, Russia

Abstrakt

Geospatial data obtained using Unmanned Aerial Vehicles (UAVs) and Unmanned Surface Vehicles (USVs) are increasingly used to model the terrain in the coastal zone, in particular in shallow waterbodies (with a depth of up to 1 m). In order to generate a terrain relief, it is important to choose a method for modelling that will allow it to be accurately projected. Therefore, the aim of this article is to present a method for accuracy assessment of topo-bathymetric surface models based on geospatial data recorded by UAV and USV vehicles. Bathymetric and photogrammetric measurements were carried out on the waterbody adjacent to the public beach in Gdynia (Poland) in 2022 using a DJI Phantom 4 RTK UAV and an AutoDron USV. The geospatial data integration process was performed in the Surfer software. As a result, Digital Terrain Models (DTMs) in the coastal zone were developed using the following terrain modelling methods: Inverse Distance to a Power (IDP), Inverse Distance Weighted (IDW), kriging, the Modified Shepard’s Method (MSM) and Natural Neighbour Interpolation (NNI). The conducted study does not clearly indicate any of the methods, as the selection of the method is also affected by the visualization of the generated model. However, having compared the accuracy measures of the charts and models obtained, it was concluded that for this type of data, the kriging (linear model) method was the best. Very good results were also obtained for the NNI method. The lowest value of the Root Mean Square Error (RMSE) (0.030 m) and the lowest value of the Mean Absolute Error (MAE) (0.011 m) were noted for the GRID model interpolated with the kriging (linear model) method. Moreover, the NNI and kriging (linear model) methods obtained the highest coefficient of determination value (0.999). The NNI method has the lowest value of the R68 measure (0.009 m), while the lowest value of the R95 measure (0.033 m) was noted for the kriging (linear model) method.
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Autorzy i Afiliacje

Oktawia Lewicka
1 2

  1. Department of Geodesy and Oceanography, Gdynia Maritime University, ul. Morska 81-87, 81-225 Gdynia, Poland
  2. Marine Technology Ltd., ul. Wiktora Roszczynialskiego 4-6, 81-521 Gdynia, Poland

Abstrakt

A navigation complex of an unmanned flight vehicle of small class is considered. Increasing the accuracy of navigation definitions is done with the help of a nonlinear Kalman filter in the implementation of the algorithm on board an aircraft in the face of severe limitations on the performance of the special calculator. The accuracy of the assessment depends on the available reliable information on the model of the process under study, which has a high degree of uncertainty. To carry out high-precision correction of the navigation complex, an adaptive non-linear Kalman filter with parametric identification was developed. The model of errors of the inertial navigation system is considered in the navigation complex, which is used in the algorithmic support. The procedure for identifying the parameters of a non-linear model represented by the SDC method in a scalar form is used. The developed adaptive non-linear Kalman filter is compact and easy to implement on board an aircraft.

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Autorzy i Afiliacje

Maria S. Selezneva
Konstantin A. Neusypin
Andrey V. Proletarsky

Abstrakt

Post-mining dumps are a common sight in the industrial areas of Silesia (Poland). Despite several reclamation projects, many of them still constitute an unresolved problem. It is not only a matter of unaesthetic view – they often pose a threat to the environment and the people living nearby. Despite revitalization, some dumps are not properly maintained and are at the risk of slope failure. Such places require constant geodetic observation and stability control. In this article, the example of a dump located in the city of Gliwice was used to show the possibilities offered by the use of photogrammetry and unmanned aerial vehicles (UAV) for cyclic checks of the embankment condition. The current state of the dump and the results of interventions after two incidents of slope failure,were observed. The main slopes of the terrain surface and at the selected cross-sections were determined in two flight missions. The obtained geometrical data were used in the further numerical analysis. Finite Element Method model representing one of the escarpment cross-sectionswas built to estimate the factor of safety and determine the main mechanisms responsible for the failure. Elastic-perfectly plastic Coulomb-Mohr model was used to describe the behaviour of the minestone and the ‘ c – tan φ reduction’ – for calculation of the stability. The problem of reliable material properties’ estimation was emphasized. The analysis included the impact of seepage and total head difference on the slope stability. It was concluded that the rainfall intensity had a decisive influence on the instability of the dump.
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Autorzy i Afiliacje

Magdalena Wróblewska
1
ORCID: ORCID
Magdalena Kowalska
1
ORCID: ORCID
Marian Łupieżowiec
1
ORCID: ORCID

  1. Silesian University of Technology, Faculty of Civil Engineering, Department of Geotechnics and Roads, Akademicka 5, 44-100 Gliwice, Poland

Abstrakt

Extremely intensive development of technology has resulted in many innovations. There are new methods of acquiring spatial data, such as laser scanning, unmanned aerial vehicles or digital non-metric cameras, which are the subject of this study. Integration of this data has become a new tool that has expanded existing measurement capabilities, finding applications in 3D modelling, archaeology and monument conservation. Owing to scanning, we can get the coordinates of almost every point of the scanned surface, obtaining full and detailed information about the object dimensions. The level of technical advancement of digital cameras allows them to be successfully used in short-range photogrammetry [27], and recently also in low-altitude aerial photogrammetry (unmanned aerial vehicles). Two different test objects were selected to achieve the intended purpose. The monument located on the 14-meter-high top of the Wanda Mound was adopted as the first object. It consists of a simple rectangular plinth made of brown marble. On its top there is a figure of an eagle with a crown of white marble. On the west wall of the plinth there is an inscription “Wanda” and a drawing showing a sword crossed with a distaff. The following features supported the choice of the monument: interesting shape of the object, which includes both simple geometric forms with large and flat surfaces (plinth), and more detailed surfaces (figure of an eagle); detailed texture of the object (complicated marble veins, wing details). The second object under study was The Helena Modrzejewska National Stary Theatre. The building was rebuilt in the style of Viennese Art Nouveau, so that it fully incorporates into the rest of buildings. Measurements included data obtained from a non-metric camera, Leica ScanStation scanner and DJI S 1000 multi-rotor.
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Autorzy i Afiliacje

Izabela Piech
1
ORCID: ORCID
Tomasz Adam
2
Paulina Dudas
2

  1. Krakow University of Agriculture, Faculty of Environmental Engineering and Land Surveying, Al. Mickiewicza 24/28, 30-059 Krakow, Poland
  2. Graduate of the University of Agriculture in Krakow, Faculty of Environmental Engineering and Land Surveying, Al.Mickiewicza 24/28, 30-059 Krakow, Poland

Abstrakt

Odor source location technology has important application value in environmental monitoring, safety emergency and search and rescue operations. For example, it can be used in post-disaster search and rescue, detection of hazardous gas leakage, and fire source detection. Existing odor source location methods have problems such as low search efficiency, inability to adapt to complex environments, and inaccurate odor source location. In this study, based on unmanned aerial vehicle technology and using swarm intelligence optimization algorithm, an improved artificial fish swarm algorithm (IAFSA) is proposed by combining curiosity in psychology on the basis of retaining the good optimization performance of the artificial fish swarm algorithm. The algorithm quantifies the curiosity of artificial fish searching high-concentration areas through a model, dynamically adjusts the artificial fish's field of vision and step length with the calculated curiosity factor, and avoids the oscillation phenomenon in the later stage of the algorithm. Simulation results show that the IAFSA has a higher success rate and smaller location error. Finally, odor source location experiments were carried out in an indoor physical environment, the feasibility of the odor source location method proposed in this study is verified in actual scenarios.
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Autorzy i Afiliacje

Tao Ding
Wenhan Zhong
Yufeng Cai

Abstrakt

In a smart city environment, Intelligent Transportation System (ITS) enables the vehicle to generate and communicate messages for safety applications. There exists a challenge where the integrity of the message needs to be verified before passing it on to other vehicles. There should be a provision to motivate the honest vehicles who are reporting the true event messages. To achieve this, traffic regulations and event detections can be linked with blockchain technology. Any vehicle violating traffic rules will be issued with a penalty by executing the smart contract. In case any accident occurs, the vehicle nearby to the spot can immediately send the event message to Unmanned Aerial Vehicle (UAV). It will check for its credibility and proceed with rewards. The authenticity of the vehicle inside the smart city area is verified by registering itself with UAVs deployed near the city entrance. This is enabled to reduce the participation of unauthorized vehicles inside the city zone. The Secure Hash Algorithm (SHA256) and Elliptic Curve Digital Signature Algorithm (ECDSA-192) are used for communication. The result of computation time for certificate generation and vehicles involvement rate is presented.
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Autorzy i Afiliacje

Suganthi Evangeline
1
Ashmiya Lenin
2
Vinoth Babu Kumaravelu
3

  1. Department of Electronics and Communication Engineering, Karunya Institute of Technology and Sciences, Coimbatore, India
  2. PG Scholar in Communication Systems, Karunya Institute of Technology and Sciences, Coimbatore, India
  3. School of Electronics Engineering, VIT University, Vellore, India

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