Using of the SPSA method to improve the accuracy of the UAV following a given route under the action of wind loads

In the modern world, UAVs (unmanned aerial vehicles) are increasingly used in everyday life in solving civilian tasks. One of the main applications of UAVs is data collection with their reference to a given coordinate system. For example, for the task of aerial photography, it is necessary to accurately link each image to the global coordinate system. In addition to the exact location of coordinates, it is worth the exact movement of a given route, to collect data of exactly those places that are needed. Thus, it is very important to ensure the minimum deviation of the UAV from the given route under the conditions of external disturbances (wind disturbances) acting on it. The article describes a procedure for assessing wind speed and direction for a UAV control system using the SPSA method. The simulation results of the algorithm operation, confirmed during flight tests on an ultralight UAV with an ardupilot autopilot, are presented.

Survey on: A variety of AQM algorithm schemas and intelligent techniques developed for congestion control

The congestion on the internet is the main issue that affects the performance of transition data over the network. An algorithm for congestion control is required to keep any network efficient and reliable for transfer traffic data of the users. Many Algorithms had been suggested over the years to improve the control of congestion that occurs in the network such as drop tail packets. Recently there are many algorithms have been developed to overcome the drawback of the drop tail procedure. One of the important algorithms developed is active queue management (AQM) that provides efficient congestion control by reducing drop packets, this technique considered as a base for many other congestion control algorithms schema. It works at the network core (router) for controlling the drop and marking of packets in the router's buffer before the congestion inception. In this study, a comprehensive survey is done on the AQM Algorithm schemas that proposed and modification these algorithms to achieve the best performance, the classification of AQM algorithms based on queue length, queue delay, or both. The advantages and limitations of each algorithm have been discussed. Also, debate the intelligent techniques procedure with AQM algorithm to achieve optimization in performance of algorithm operation. Finally, the comparison has been discussed among algorithms to find the weakness and powerful of each one based on different metrics.

Individual Tree Crown Detection Using UAV Orthomosaic

Unmanned Aerial Vehicles (UAVs) are increasingly used in forestry as they are economical and flexible. This study aims to present the advantages of the drone photogrammetry method in collecting individual tree crowns, as individual tree crown detection could deliver essential ecological and economic information. The referred accuracy for individual tree crown extraction is 79.2%. Only crowns that were clearly visible were selected and manually delineated on the image because the distribution of the true crown size is significantly different from the segmented crowns. The aim of this study is to investigate UAVs orthomosaics in individual tree crown detection. The objectives of this study are to produce the orthomosaic of tree crown extraction mapping using the Pix4D software and analyze the tree crowns using tree crown delineation and the OBIA algorithm. Data processing involves the processing of aerial images using Pix4Dmapper. Automatic tree crown detection involves a tree crown delineation algorithm and OBIA operations to process the tree crown extraction. The crown delineation algorithm and OBIA algorithm operation will be compared to the actual tree crown measurement in terms of diameter and area. The tree crown delineation method obtained a 0.347m mean diameter difference from the actual tree crown diameter, while the OBIA approach obtained 4.98m. The tree crown delineation method obtained 97.26% of the actual tree crown area, while OBIA obtained 91.74%.

Automatic movement control system of the semi-trailer truck for maneuvering on the territory of the distribution center

The article is devoted to the development of an algorithm for the operation of an electronic control system for the movement of a semi-trailer truck on the territory of a distribution center using satellite-based navigation systems. A diagram of the interaction of software and hardware parts of the control system is presented. The algorithm of the controller has been compiled. The evaluation of the algorithm operation was carried out by simulation method testing.

Satellite Differential Code Bias Estimated Using EGYNET: A Local Egyptian Permanent Network

This paper proposes to determine the GPS satellites DCB using nine GPS receivers located in the middle of Egypt. During four seasons and 36 days characterized by quiet geomagnetism, the performance of the proposed method is examined. The dual GPS data selected is used and applied to the GPS receiver chain notes. The Bernese program V.5 is used to estimate DCBs from the data of a single GPS station where the results of the algorithm operation are compared to the CODE DCB data and the main differences in GLONASS data are recorded. According to the comparison of the results between the proposed method and the currently existing methods, it can be shown that the accuracy of the DCB estimates is at a level of about 0.31 and 0.17 ns.

A Comprehensive Algorithm for Detection, Identification of Naval Surface Forces and Target Allocation of Network-Centric Controlled Weapons

The purpose of the study was to examine and solve the problem of detecting and identifying the objects of naval surface forces by a group of controlled weapons within the group using coordinates and the type of such objects. The main target of naval surface forces was determined according to the parameters of the frequency of detection of the objects by the group of controlled weapons and the reliability of identification of the objects of naval surface forces. A matrix for detecting the objects of naval surface forces by the group of controlled weapons has been formed and analyzed. The introduction of restrictions on the tactics of actions of the group of controlled weapons and on the coefficient of convolution of criteria in the task of target allocation makes it possible to ensure almost complete absence of intersections of trajectories of controlled weapons. On the basis of statistical modeling of the configuration of the systems and the corresponding probabilities of detection and identification, the effectiveness of the developed algorithm is shown. An example of a multi-stage calculation of one variant from a statistical series of experiments is given, followed by a preliminary assessment of target allocation by the group of controlled weapons in accordance with the current configurations of the group of weapons and naval surface forces. The multivariate analysis of the efficiency of the algorithm operation on various configurations of the systems showed a high degree of identification of the objects of naval surface forces in comparison with the existing algorithms. A range of values for the probabilities of identifying the types of the objects of naval surface forces by the group of controlled weapons has been identified, which provides an almost unambiguous determination of the main target of naval surface forces

Computer Simulation of a Group of Mobile Robots in Special Software Tools

The problem of controlling a group of special robots for application in the high-risk conditions (for example, for fire extinguishing, search for hazardous substances, or elimination of consequences of emergencies) is solved. According to the task, robots operate in the industrial and urban environment, i.e., the movement of robots is planar. Various strategies of group interaction between robots are analyzed; a literature review is conducted. Due to the task specifics, a decentralized management strategy has been selected. For solving the problem, a movement algorithm of a group of mobile robots with a subsequent visual check of the resulting algorithm operation is proposed. Implementation of the algorithm’s work is performed in the MATLAB environment. For preliminary algorithm verification and modeling of various dangerous cases, a model of robot group using the Mobile Robotics Simulation Toolbox of MATLAB was made. For a more detailed and accurate analysis of the real robot’s behavior, a model in the ROS package has been developed. That model interacts with the developed algorithm through the ROS Toolbox package of MATLAB. This software can be used for the training of engineering staff in the field of mathematical modeling, group control, and multi-agent systems. As a result of verification, the program and the model successfully solve the task. Yet, the model in the ROS package requires greater computational power because of the large number of complex calculations.

Study of Algorithms for Wind Direction Retrieval from X-Band Marine Radar Images

After decades of research, X-band marine radars have been broadly used for wind measurement. For retrieving the wind direction based on the wind-induced streaks, a lot of effort has been expended on three celebrated approaches—the local gradient method (LGM), the adaptive reduced method (ARM), and the energy spectrum method (ESM). This paper presents a scientific study of these methods. The contrast of retrieving the real measured marine radar images and vane measured results is evaluated, in perspective of the error statistics and algorithm operation efficiency. Interference factors, such as the historical information of the measured area, reference wind speed, and sea condition showing in the monitoring equipment are also concerned. The tentative results showed that LGM is robust, which can be implemented in most radar images, because it allows for a lower selection of requirements compared with the other two methods. For ARM, the better retrieval performance is a tradeoff with extra computation, which is expensive. ESM is superior to the other two algorithms in terms of accuracy and computation load; however, this algorithm is sensitive in rain-contaminated radar images, meaning it is a good choice for data post-processing in the lab.

INTELLIGENT ALGORITHM OF IDENTIFYING DESTRUCTIVE INFORMATION IN THE TEXT

In the context of ensuring the information and psychological security of a society in the Russian Federation, the problem of uncontrolled growth of the Internet destructive content is being considered. The problem of search and identification of destructive information demands the minimal subjectivity and the maximum automation, because it is still solved generally by expert methods with drawing up registers of the forbidden sources. Existing search methods (expert processing, thematic search, intelligent data processing methods) used to find specific words in the text have been considered, the advantages and disadvantages of these methods have been stated. For solving the task set the intellectual algorithm of the modified search of destructive content has been suggested using foul language in the textual information as an example. The suggested approach has a different system of self-replenishment of the dictionary on the basis of identification of the unknown words as foul ones. The correctness of the dictionary replenishment is controlled by an expert. A detailed description of the developed algorithm has been presented. The example of the algorithm operation and initial results of its approbation are given.