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3. Optimal Capacity Configuration of Hybrid Energy Storage Systems for Smoothing Photovoltaic Power Fluctuation

Author

Zhu, Weiguo, Xu, Wenyue, Niu, Cong, Jiang, Sheng, Han, Wei, Song, Xiaotong, Shi, Qianqian, Angrisani, Leopoldo, Series Editor, Arteaga, Marco, Series Editor, Chakraborty, Samarjit, Series Editor, Chen, Jiming, Series Editor, Chen, Shanben, Series Editor, Chen, Tan Kay, Series Editor, Dillmann, Rüdiger, Series Editor, Duan, Haibin, Series Editor, Ferrari, Gianluigi, Series Editor, Ferre, Manuel, Series Editor, Jabbari, Faryar, Series Editor, Jia, Limin, Series Editor, Kacprzyk, Janusz, Series Editor, Khamis, Alaa, Series Editor, Kroeger, Torsten, Series Editor, Li, Yong, Series Editor, Liang, Qilian, Series Editor, Martín, Ferran, Series Editor, Ming, Tan Cher, Series Editor, Minker, Wolfgang, Series Editor, Misra, Pradeep, Series Editor, Mukhopadhyay, Subhas, Series Editor, Ning, Cun-Zheng, Series Editor, Nishida, Toyoaki, Series Editor, Oneto, Luca, Series Editor, Panigrahi, Bijaya Ketan, Series Editor, Pascucci, Federica, Series Editor, Qin, Yong, Series Editor, Seng, Gan Woon, Series Editor, Speidel, Joachim, Series Editor, Veiga, Germano, Series Editor, Wu, Haitao, Series Editor, Zamboni, Walter, Series Editor, Tan, Kay Chen, Series Editor, Yang, Qingxin, editor, Li, Zewen, editor, and Luo, An, editor

Published
2024
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9. Path planning, modelling and simulation for energy optimised mobile robotics

Author

Niu, Cong and Yan, Xiu-Tian

Abstract

This thesis is concerned with an investigation of a solution for mobile robotic platforms to minimize the usage of scarce energy that is available and is not wasted following traditionally planned paths for complex terrain environments. This therefore addresses the need to reduce the total energy cost during a field task or mission. A path planning algorithm is designed by creating a new approach of artificial potential field method that generates a planned path, utilising terrain map. The new approach has the capability of avoiding the local minimum problems which is one of the major problems of traditional potential field method. By solving such problems gives a reliable solution to establish a required path. Therefore the approach results in an energy efficient path of the terrain identified, instead obvious straight line of the terrain. A literature review is conducted which reviews the mainstream path planning algorithms with the applications in mobile robotic platforms was analysed. These path planning algorithms are compared for the purpose of energy optimized planning, which concludes the method of artificial potential field as the path planning algorithm which has the most potential and will be further investigated and improved in this research. The methodology of designing, modelling and simulating a mobile robotic platform is defined and presented for the purpose of energy optimized path planning requirement. The research is to clarify the needs, requirements, and specifications of the design. A complete set of models which include mechanical and electrical modelling, functional concept modelling, modelling of the system are established. Based on these models, an energy optimized path planning algorithm is designed. The modelling of force and the kinematics is established to validate and evaluate the result of the algorithm through simulations. Moreover a simulation environment is established which is constructed for multi perspective simulation. This also enables collaborative simulation using Simulink and ADAMS to for simulating a path generated by the path planning algorithm and assess the energy consumption of the driven and steering mechanism of an exemplar system called AgriRover. This simulation environment allows the capture of simulated result of the total energy consumption, therefore outlines the energy cost behaviour of the AgriRover. A total of two sets of paths was tested in the fields for validation, one being generated by the energy optimized path planning algorithm and the other following a straight path. During the field tests the total cost of energy was captured . Two sets of results are compared with each other and compared with the simulation. The comparison shows a 21.34% of the energy saving by deploying the path generated with the energy optimized path planning algorithm in the field test. This research made the following contribution to knowledge. A comparison and grading of mainstream path planning algorithms from energy optimisation perspective is undertaken using detailed evaluation criteria, including computational power required, extendibility, flexibility and more criteria that is relevant for the energy optimized planning purpose. These algorithms have not been compared from energy optimisation angle before, and the research for energy optimised planning under complex terrain environments have not been investigated. Addressing these knowledge gaps, a methodology of designing, modelling and simulating a mobile platform system is proposed to facilitate an energy optimized path planning. This , leads to a new approach of path planning algorithm that reduces unnecessary energy spend for climbing of the terrain, using the terrain data available. Such a methodology derives several novel methods: Namely, a method for avoiding local minimum problem for artificial potential field path planning using the approach of approximation; A method of achieving high expendability of the path planning algorithm, where this method is capable of generate a path through a large map in a short time; A novel method of multi perspective dynamic simulation, which is capable of simulating the behaviour of internal mechanism and the overall robotic mobile platform with the fully integrated control, The dynamic simulation enables prediction of energy consumption; Finally, a novel method of mathematically modelling and simplifying a steering mechanism for the wheel based mobile vehicle was further investigated.

Published
2021
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17. Post-stack multi-scale fracture prediction and characterization methods for granite buried hill reservoirs: a case study in the Pearl River Mouth Basin, South China Sea.

Author

Liu, Junping, Zhou, Huailai, Liao, Luyao, Niu, Cong, Li, Qiuyu, Zhang, Jian, and Bai, Min

Subjects
WATERSHEDS, GAS condensate reservoirs, GRANITE, GAS reservoirs, NATURAL gas prospecting, PETROLEUM prospecting
Abstract

Granite buried hill oil and gas reservoirs are relatively scarce worldwide, and the fine prediction and characterization of their fractures have always been a significant industry challenge. Particularly in the South China Sea region, large and thick granite buried-hill reservoirs are influenced by various geological processes such as weathering and tectonics, resulting in a complex internal fracture system. The seismic reflection characteristics exhibit high steepness, discontinuity, and significant amplitude differences, posing significant difficulties for the fine characterization of fractures. A systematic and comprehensive research approach has not yet been established. Therefore, this study considers the large granite-buried hill A reservoir in the South China Sea as a typical case study and proposes a multi-scale fracture fine prediction and characterization methodology system. The method starts with analyzing the fracture scale and genesis to refine the fracture scales identifiable by conventional seismic data. Based on this, the U-SegNet model and transfer learning are utilized to achieve fine detection of large-scale fractures. Meanwhile, using highresolution ant tracking technology based on MVMD frequency division and sensitive attribute preferences realizes a fine prediction of medium-to-small-scale fractures. Furthermore, the discrete fracture network is used for fracture deterministic modeling, ranging from geometric morphology to percolation behavior. Ultimately, a post-stack seismic multi-scale fracture prediction and characterization workflow is established. The results indicate that the buried hill in the study area exhibits a high degree of fracture development with evident multi-scale characteristics. Among them, large-scale fractures have a relatively low development density, primarily oriented in the NW and NE directions; medium-to-small-scale fractures exhibit high-density and omnidirectional development. The development of fractures significantly improves the storage space and fluid flow capacity of the buried hill. Compared with traditional methods, the proposed method notably enhances the accuracy of characterizing the degree of fracture development, spatial morphology, and percolation behavior in the buried hill reservoir, providing a scientific basis for oil and gas exploration and development. [ABSTRACT FROM AUTHOR]

Published
2024
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23. List of contributors

Author

Birrell, Simon Andrew, primary, Cox, Ian, additional, den Uijl, Ingrid, additional, Hasan, Narjis, additional, Hughes, Josie, additional, Li, Youhua, additional, Lida, Fumiya, additional, Lynch, Patrick Joseph, additional, Lynham, Paul, additional, Minaei, Negin, additional, Mottram, Toby, additional, Niu, Cong, additional, Quealy, Sinead, additional, Ross, Dave, additional, Schlingmann, Norbert, additional, Thomson, Willie, additional, and Yan, Xiu-Tian, additional

Published
2022
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25. Simultaneous random noise attenuation and three‐dimensional seismic‐data interpolation with faster adaptive rank reduction.

Author

Wang, Jianhua, Wang, Yandong, Niu, Cong, and Sun, Wenbo

Subjects
RANDOM noise theory, SINGULAR value decomposition, INTERPOLATION, INFORMATION theory, SIGNAL-to-noise ratio, KRYLOV subspace, SPECTRUM analysis
Abstract

Rank‐reduction‐based simultaneous random noise attenuation and three‐dimensional seismic‐data interpolation has recently become a hot topic in reflection seismology. However, the rank of traditional methods is fixed without considering the variation of signal‐to‐noise ratio on different frequency components, leading to serious residual noise and further affecting the following processing and interpretation tasks. In addition, traditional methods also heavily rely on the application of singular value decomposition technique for rank reduction, which is proven to be computationally expensive for large‐scale data. Thus, a fast‐adaptive rank‐reduction method is proposed in this study. First, the information entropy theory is introduced to adaptively select the optimal rank at various frequencies by calculating the increment of singular entropy. Second, we propose a fast Random Block Krylov algorithm and a subspace multiplexing technique to replace the singular value decomposition algorithm used in traditional methods. The proposed method can significantly improve computational efficiency and yield better seismic‐data reconstruction performance than traditional methods. Applications of the proposed approach on both synthetic and field seismic data demonstrate its superior performance over a well‐known rank‐reduction‐based method, that is the random multi‐channel singular spectrum analysis, in terms of recovered signal‐to‐noise ratio and visual view. [ABSTRACT FROM AUTHOR]

Published
2024
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36. Facile synthesis, crystal structure, quantum calculation, and biological evaluations of novel selenenyl sulfide compounds as potential agrochemicals

Author

Shang, Ming‐Hao, primary, Sun, Xue‐Wen, additional, Wang, Hai‐Lian, additional, Li, Hao‐Ran, additional, Zhang, Jia‐Shuang, additional, Wang, Li‐Zhong, additional, Yu, Shu‐Jing, additional, Zhang, Xiao, additional, Xiong, LI‐Xia, additional, Li, Yong‐Hong, additional, Niu, Cong‐Wei, additional, and Wang, Jian‐Guo, additional

Published
2023
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38. Sensor Fusion-Based UAV Localization System for Low-Cost Autonomous Inspection in Extremely Confined Environments

Author

Yang, Beiya, Yang, Erfu, Yu, Leijian, and Niu, Cong

Abstract

Utilizing the unmanned aerial vehicle (UAV) for autonomous inspection in extremely confined environments has become a much sought research area, due to the pressing industrial needs. To provide the high-accuracy position information of UAV in such environments, the ultrawideband (UWB)-based localization technology has been one of the ideal candidates. However, the unpredictable propagation condition and the geomagnetic disturbances for inertial measurement unit (IMU) will all have huge impact on the positioning performance with the single UWB and the IMU/UWB-based loosely coupled (LC) sensor fusion approach. Therefore, a tightly coupled adaptive extended Kalman filter (TC-AEKF)-based sensor fusion UAV localization system is proposed and developed in this article for autonomous inspection in extremely confined environments. The proposed system can attain high-accuracy localization of UAV with 0.097-m median error, 0.167-m 95th percentile error, and 0.039-m average standard deviation (STD). The drift led by the geomagnetic disturbances for IMU is greatly reduced with the estimation error of the roll, pitch, and yaw angle to be 2.15°, 1.54°, and 4.58°, respectively. Finally, an autonomous inspection experiment has been conducted to prove the effectiveness of the proposed system and algorithm for actual application, and the video from it has been attached in https://youtu.be/nEgvwbIVRRk.

Published
2024
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47. The effect of paddle configurations on particle mixing in a soil-fertilizer continuous mixing device

Author

Ma Shuai, Xu Liming, Yuan Quanchun, Yan Chenggong, Zhao Shijian, and Niu Cong

Subjects
Convection, Materials science, General Chemical Engineering, 02 engineering and technology, Mechanics, 021001 nanoscience & nanotechnology, Discrete element method, Contact force, Auger, 020401 chemical engineering, Paddle, Particle velocity, 0204 chemical engineering, 0210 nano-technology, Mixing (physics), Magnetosphere particle motion
Abstract

The mixing of soil and fertilizer is critically important for the deep application of organic fertilizer. The mixing of soil and fertilizer generally needs to be conducted during the transportation process. Here, a screw auger with paddles was used to improve the mixing performance of particles during the transport of materials. The discrete element method (DEM) and experimental measurements were used to characterize the effect of paddle configurations on particle mixing. Four parameters with five levels were used in the simulations. The paddle configurations had a major effect on the mixing performance and granular behavior. The relative standard deviation (RSD) results obtained from the validated DEM models revealed that devices with larger paddle rotational speeds n, sideward angles α, pitch angles β and 3 paddles conferred higher mixing performance. The effect of paddle configurations on the paddle-particle and particle-particle average contact forces was also analyzed. Higher paddle rotational speeds n, sideward angles α and pitch angles β led to larger average normal contact forces, and the effect of the number of paddles N was small. Analysis of the particle velocity distribution of different configurations revealed that an appropriate paddle configuration with better mixing performance improved the particle velocity. The contributions of both convective and diffusive mechanisms on particle motion were studied, and convection was found to be the dominant mechanism. Generally, the results of this study provide a reference for the selection of an appropriate paddle configuration that confers higher mixing performance and lower power consumption.

Published
2021

48. Discrete element method optimisation of a scraper to remove soil from ridges formed to cold-proof grapevines

Author

Haochao Tan, Ma Shuai, Xu Liming, Niu Cong, and Yan Chenggong

Subjects
Scraper site, Entry angle, Control and Systems Engineering, Field experiment, Soil Science, Soil science, Agronomy and Crop Science, Geology, Discrete element method, Food Science
Abstract

A scraper is the most commonly used tool for removing soil from ridges used to cold-proof vines grown in northern China. It can have different complex shapes and its structure and working parameters are vital for effectively removal soil and saving energy. In this study, the interaction between the scraper and the soil was simulated using discrete element method (DEM) simulation, and a calibrated DEM model was developed to simulate soil removal of the scraper. The scraper with different profiles (straight-line, arc, and parabola), different entry angle (δ) and different wing opening angle (θ) were simulated and analysed at various forward speeds (v) in DEM model. The draught force and bilateral soil throw width of the scraper were used to evaluate the effect of soil removal. The DEM model was verified by field experiment, and the draught force and bilateral soil throw width in DEM simulation were compared with the field experiment and the relative errors were 5.97% and 2.88%, respectively. This shows that the DEM model can accurately simulate and optimise the scraper. In order to achieve the best soil removal effect, that is to minimise the draught force and to maximise the bilateral soil throw width, the scraper with arc profile was selected and the optimised values of δ, θ and v were 60°, 86° and 0.6 m s−1, respectively. The corresponding optimal values of draught force and bilateral soil throw width were 58.55 N and 1223 mm, respectively, and based on the optimized parameters, the optimisation results were verified.

Published
2021

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