Development of Two Control Strategies for Tracking the Trajectory of An Unmanned Underwater Structure Inspection VehicleRiaño, Yorley Dayana Caro; Prada, Sebastián Roa
doi: 10.1088/1742-6596/2224/1/012097pmid: N/A
This paper presents the development of two dual-loop control strategies for an underwater Remotely Operated Vehicle, ROV. The first strategy consists of two PID controllers while the second one features a LQG controller in the inner loop, and a PID controller in the outer loop. The transient response of the two strategies is compared when an anti-windup gain is applied and when there is no anti-windup gain, and a way to tune this gain in the case of statespace controllers is proposed. For further comparison, the strategies are simulated for a variable set point, for the three variables to be controlled, x, z, yaw, so that both their tracking and the effect of coupling can be seen. In conclusion, the use of anti-windup gain is recommended for control systems that reach saturation, so that they can react quickly when they are in an operating zone, and the use of a random matrix for the calculation of this gain in state-space controllers is suggested.
Joint Optimization of Resource Allocation and UAVs’ Trajectories in Multi-UAV-Aided MEC SystemsWu, Runuyang
doi: 10.1088/1742-6596/2224/1/012122pmid: N/A
The combination of unmanned aerial vehicles (UAVs) and mobile edge computing (MEC) has become an up-and-coming technique to provide additional computing support for smart mobile devices with limited battery capacity in the wireless communication network systems. In this paper, a multi-UAV-aided MEC system is modelled where UAVs are equipped with MEC servers and users can execute local computing and computation offloading to UAVs simultaneously. The total amount of processing bits of all users is maximized by the joint optimization of the user-UAV association, local processing frequency, transmit power, bandwidth allocation and UAVs’ trajectories, meanwhile, the energy consumption constraint and the UAVs’ speed constraint are satisfied. Because the formulated problem is not convex, it is challenging to get the global optimal solution directly. To iron out the non-convex problem, it is divided into three subproblems and solved by an alternating optimization algorithm. Simulations show that the algorithm introduced in our paper performs better than the local computing, full offloading and fixed trajectory patterns.
QoS Assessment for Video and Audio Data based on a Testbed for Multimedia Wireless ad Hoc NetworksAnh, Ngo Hai; Giang, Pham Thanh
doi: 10.1088/1742-6596/2224/1/012075pmid: N/A
Currently, with the fast modernization of wireless networking technologies as well as the very complex needs of the network users, multimedia data takes for a large proportion in the types of network services, this type of data requires Quality of Service (QoS) differs from traditional data, by ensuring the listening and viewing elements of the user. In this paper, we analyse the effect of video and voice data on QoS of wireless network services based on the establishment of an experimental evaluation (emulation) system or testbed, thereby providing empirical analysis on the effect of multimedia data on mobile wireless QoS.
An Optimization Method for Clearance Value of Electric Submersible Screw PumpFang, Wang; Fei, Cao; Chunqing, Lin; Yaming, Li; Wei, Xie; Yun, Li; Mengshi, Yang; Jing, Wang; Jingwen, Zhao
doi: 10.1088/1742-6596/2224/1/012123pmid: N/A
Electric submersible screw pump often works at high speed, which has the characteristics of high speed, high temperature and large rubber deformation. In case of sudden shutdown, the rubber will not shrink at high temperature, which may lead to serious accidents such as pump locking and electrode burning. In the initial stage of pump start-up and restart after pump shutdown, due to the above reasons, it is often difficult to start the pump, which makes the pump unable to work normally. Therefore, this paper studies the clearance value of the electric submersible screw pump, calculates and tests the interference amount and initial interference amount, improves and optimizes the clearance value of the electric submersible screw pump, effectively improves the working efficiency and service life of the electric submersible screw pump, achieves the purpose of improving the quality and efficiency of oilfield production, and has a very important practical significance for the development of the rodless pump market.
Resource Allocation Algorithm Based on Modeling of Ubiquitous Network Node CapabilitySong, Dai; Chen, Xushan; Rui, Lanlan; Li, Wenjing; Du, Zongpeng; Li, Zhiqiang; Lu, Lu
doi: 10.1088/1742-6596/2224/1/012089pmid: N/A
With the continuous development and progress of the Internet, computing power is gradually moving from the center to the edge. In order to perceive, measure, schedule and manage the distributed computing resources, it is necessary to model and evaluate the node capability. Based on the development trend of network computing convergence and the demand of network computing service scheduling, this paper studies the unified measurement model and resource allocation algorithm for the integration of network computing and heterogeneous resources. The node resources are divided into four dimensions: computing, communication, memory and storage, and on this basis, the comprehensive ability evaluation index is proposed. Through simulation analysis, the effectiveness of the resource allocation algorithm based on node capability modeling is verified.
Theory and Practice of Creating a Two Energy Outputs MagnetronChuryumov, G; Qiu, S; Wang, N; Li, W
doi: 10.1088/1742-6596/2224/1/012100pmid: N/A
This paper presents the methodology for 3-D simulation and design of the magnetron with two energy outputs. The principal functionality of the modified magnetron, both theoretically and experimentally, has been determined. The central distinguishing feature of this magnetron (for example, unlike the conventional magnetron with one output) is the availability of second energy output in the anode block. The mathematical models of both the resonant anode block and the electron-wave interaction are described. The dispersion characteristics of the anode block for cavities various geometries are given. It is supposed that forming the total RF field in the interaction space results from the interference of RF fields excited severally in the resonant anode block consisting of the small and large cavities (resonators). For PIC-simulation of electron-wave interaction in the dual-output magnetron, the non-linear system of equations is stated as a self-consistent system containing the equation of motion (for electron stream), the equation of excitation (for RF field), and Poisson’s equation for calculating the space-charge field. The fundamental feature of the self-consistent system of equations is a new algorithm for determining the Coulomb interaction forces. The implementation of the mathematical model made it possible not only to gain new knowledge about the physical processes in the magnetron but also to determine its output characteristics. On operating frequency of ∼ 13.34 GHz, at an anode voltage of 495 V, a magnetic field of ∼ 0.25 T, and with air cooling of the magnetron, there were obtained the following limiting values: the RF output power of ∼ 14.6 W and the power conversion efficiency of ∼ 40.8%. The use of the second energy output allowed extending the magnetron’s functionality and implementing the modes of the frequency tuning (adjunction) and its stabilization. The simulation results are in good agreement with the experiment.To the 100th anniversary of magnetron
A Comparative Study: The Benefits of a Novel Illuminance Calculation Method over Luminance Calculation Method for Optimal Roadway Lighting Design ApplicationsThurairajah, U
doi: 10.1088/1742-6596/2224/1/012117pmid: N/A
This paper discusses the challenges and impacts of the luminance calculation method for roadway lighting applications and recommends a novel illuminance calculation method as the most suitable for Roadway Lighting Applications. This change would reduce the costs of roadway lighting design without increasing risks, which will benefit society and the profession. Luminance calculations are complicated and take approximately five times longer than the new illuminance calculation method, provide no additional insight, and result in the same design outcome. This paper makes a comparative study and analyzes both methods using regular comparative assessment and quantitative and qualitative assessments and provides a solution to the over 50-year-old challenge. The quantitative evaluation uses a sample case study and examines its corresponding benefit-cost ratio. The qualitative approach is to complete a survey among the peers and the lighting designers. This is the first paper to address all these parameters of roadway lighting holistically. This paper will be helpful for academics, researchers, scientists, engineers, consultants, architects, lighting designers, contractors, developers, financial institutions, and government agencies funding outdoor lighting.
X-Ray Pulsar-based Navigation Scheme for Solar System Boundary ExplorationWang, Y S; Wang, Y D; Zheng, W; Song, M Z
doi: 10.1088/1742-6596/2224/1/012127pmid: N/A
For solar system boundary exploration mission, this paper designed an X-ray pulsar-based navigation (XNAV) scheme. The Fisher information matrix is used to choose optimal pulsar observation configuration. Based on the selected pulsar configuration, the accuracy of pulsar navigation and stellar angle navigation is compared. Besides, the navigation performance of XNAV is verified by the orbits of voyager 1, voyager 2 and pioneer 10 respectively. Simulation results show that the pulsar navigation could provide accurate positioning results for solar system boundary explorers.
UCB-DQN based Joint Beamforming and Power Control for Software Defined UAV Swarm NetworkLi, Haitao; Zhang, Shuai; Fang, Zheng; Qiu, Qiming
doi: 10.1088/1742-6596/2224/1/012101pmid: N/A
In this paper, we address the problem of deep Q-Network (DQN) based joint power control and beamforming for enabling interference suppression in software defined UAV swarm (SD-UAS) network. We first present the optimization model of joint beamforming and power control (JBPC). Then, to solve this joint optimization problem, we make use of UCB exploration in the learning process of DQN. Simulation results validate that the convergence obtained with the proposed UCB-DQN strategy outperform the DQN learning algorithm, which can to raise the exploration efficiency and sequentially speed up the convergence for the JBPC problem. It is benefit to supress interference and enhance the SD -UAS communication performance.
A Comparative Study on Part-of-Speech Taggers’ Performance on Examination Questions Classification According to Bloom’s TaxonomyGoh, Thing Thing; Jamaludin, Nor Azliana Akmal; Mohamed, Hassan; Ismail, Mohd Nazri; Chua, Huang Shen
doi: 10.1088/1742-6596/2224/1/012001pmid: N/A
Examination questions classification according to Bloom’s Taxonomy uses Natural Language Processing (NLP) approach, a series of text processing approach that generally can divided into the keywords identification stage and then the identified keywords classification to Bloom’s Taxonomy levels stage. Since this NLP approach is a pipeline processes, the keywords identification stage’s performance in term of accuracy is affecting the subsequent stage - the identified keywords classification and subsequently limits the final accuracy performance of the questions classification. The keywords identification stage’s performance is mainly depending on the effectiveness of Part-Of-Speech (POS) tagging. Thus, this paper aims to identify the best performing POS tagger in keywords identification stage and enhance the tagger’s performance with rule-based approach to achieve high accuracy performance and benefit the subsequent keyword classification and then the questions classification accuracy. The Perceptron tagger and the Stanford POS tagger are selected to be evaluated their performance in identifying the keywords of the randomly selected 200 examination questions from STEM subjects. This paper has observed the Stanford POS tagger is the best performing tagger in POS tagging with accuracy of 80.5%. Some rules are applied to the POS tagging to improve the accuracy further to 91.5%.