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Research Progress on Calculation and control of Unaccounted for Gas of Natural Gas Pipeline Network

Journal of Physics: Conference Series 2021年第1期2076卷

作者： Huiyu Chen Shanshan Li Lili Zuo Wanjun Li Research Institute of Natural Gas Technology PetroChina Southwest Oil & Gasfield Company/Key Laboratory of Natural Gas Quality Control & Energy Measurement PetroChina Southwest Oil & Gasfield Company Chengdu Sichuan 610213 China National Engineering Laboratory of Pipeline Transmission Safety/Key Laboratory of Petroleum Engineering Ministry of Education/Beijing Key Laboratory of Urban Oil and Gas Distribution Technology China University of Petroleum (Beijing) Beijing 102249 China

At present, volume measurement is still used in transfer measurement of natural gas in China, so the calculation and management of Unaccounted for Gas are based on volume measurement. With the change of natural gas measurement method from volume measurement to energy measurement, the calculation and management of Unaccounted for Gas based on energy measurement will be paid more and more attention. This paper investigates the calculation methods and management measures of Unaccounted for Gas based on volume measurement in China and Unaccounted for Gas based on energy measurement in other countries, and compares the research progress. The results show that: the general principles of Unaccounted for Gas calculation in China and other countries are basically the same, but the calculation formulas are not completely the same. All countries consider the input gas, output gas, line pack variation and self-consumption gas. On this basis, Italy considers the known leakage, and Britain considers the known leakage and the daily calorific value shrinkage caused by its settlement rules. In order to reduce Unaccounted for Gas, the UK regularly verifies meter, carries out the research on Unaccounted for Gas baseline, and actively participates in the global Unaccounted for Gas benchmarking. Australia replaces the old main line and reduces the operation pressure of pipeline, which significantly reduces Unaccounted for Gas. The calculation methods and control measures of Unaccounted for Gas based on energy measurement in Italy, Britain and Australia can be used for reference in China.

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Generation and storage of spin squeezing via learning-assisted optimal control

arXiv

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arXiv 2020年

作者： Tan, Qing-Shou Zhang, Mao Chen, Yu Liao, Jie-Qiao Liu, Jing Key Laboratory of Hunan Province on Information Photonics and Freespace Optical Communication College of Physics and Electronics Hunan Institute of Science and Technology Yueyang414000 China MOE Key Laboratory of Fundamental Physical Quantities Measurement Hubei Key Laboratory of Gravitation and Quantum Physics PGMF and School of Physics Huazhong University of Science and Technology Wuhan430074 China Tencent Lightspeed & Quantum Studios Shenzhen China Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Key Laboratory for Matter Microstructure and Function of Hunan Province Department of Physics Synergetic Innovation Center for Quantum Effects and Applications Hunan Normal University Changsha410081 China

The generation and storage of spin squeezing is an attractive topic in quantum metrology and the foundations of quantum mechanics. The major models to realize the spin squeezing are the one- and two-axis twisting models. Here, we consider a collective spin system coupled to a bosonic field, and show that proper constant-value controls in this model can simulate the dynamical behavior of these two models. More interestingly, a better performance of squeezing can be obtained when the control is time-varying, which is generated via a reinforcement learning algorithm. However, this advantage becomes limited if the collective noise is involved. To deal with it, we propose a four-step strategy for the construction of a new type of combined controls, which include both constant-value and time-varying controls, but performed at different time intervals. Compared to the full time-varying controls, the combined controls not only give a comparable minimum value of the squeezing parameter over time, but also provides a better lifetime and larger full amount of squeezing. Moreover, the amplitude form of a combined control is simpler and more stable than the full time-varying control. Therefore, our scheme is very promising to be applied in practice to improve the generation and storage performance of squeezing. © 2020, CC BY-NC-SA.

关键词： Reinforcement learning

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Numerical Optimization of 2-D Luneburg Lens Antenna by Distorting the Permittivity Estimation to Improve the Beam Radiation

Numerical Optimization of 2-D Luneburg Lens Antenna by Disto...

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European Conference on Antennas and Propagation, EuCAP

作者： Hsi-Tseng Chou Yi-Sheng Chang Hao-Ju Huang Zhi-Da Yan Danai Torrungrueng Graduate Institute of Communication Engineering National Taiwan University Taipei Taiwan Department of Electrical Engineering Yuan Ze University Taiwan The Industrial Electric and Control System Research Center Faculty of Technical Education King Mongkut’s University of Technology North Bangkok Bangkok Thailand

This paper presents the design procedure of two-dimensional (2-D) Luneburg lens antennas based on numerical optimization of radiation and dielectric permittivity to improve the radiation patterns. A 2-D lens structure is considered for its extremely low profile realizable by dielectric substrates. The lens is discretized into several discrete concentric rings whose values of permittivity are optimized by two approaches of fitting them to the ideal curve in a minimum least square error (MLSE) fashion, and numerical simulation of radiation, respectively. The effects of this optimization are examined and validated by numerical simulation. Experimental results are also briefly discussed.

关键词： Lenses Permittivity Optimization Dielectrics Antenna radiation patterns Estimation

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Research on Chaos Electromagnetic Mechanism Fusion Algorithm Based on Logistic Mapping

Research on Chaos Electromagnetic Mechanism Fusion Algorithm...

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2018 3rd International Conference on Modelling, Simulation and Applied Mathematics(MSAM 2018)

作者： Xunlai He Junhui Yin Weizhao Zhang Zhenqian Yang Nantong Institute of Technology Shijiazhuang campus of Army Engineering University Xi'an Satellite Measurement and Control Center

For multi-component, strong nonlinear systems, especially when considering component elasticity and gaps, it is difficult to obtain high-order information such as required gradients through calculations. It will face problems such as fewer iterations and inconspicuous optimization results, and because of the objective function. The non-linear features make it difficult to achieve optimal calculations. In this paper, by introducing Logistic chaotic maps to enrich the search behavior, the global optimization ability of the standard electromagnetic algorithm is improved. The test results show that the improved EM algorithm introduced with the chaos mechanism, the CEM algorithm, improves both the accuracy of the solution and the convergence efficiency. For solving high-dimensional function optimization problems. At the same time, it is found that the better initial population is of great significance for speeding up the optimization process, and the initial fitness can be improved by adopting multiple initial population selection and setting elite solutions.

关键词： nonlinear systems logistic mapping EM algorithm multi-objective optimization chaos local search charged particles

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A Multipart 5G Base-Station Antenna Using Series-Fed Patch Antenna Sub-Arrays

A Multipart 5G Base-Station Antenna Using Series-Fed Patch A...

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2018 IEEE Antennas and Propagation Society International Symposium and USNC/URSI National Radio Science Meeting, APSURSI 2018

作者： Lai, Fei-Peng Li, Hsueh-Jyh Li, Chi-Min Wang, Pao-Jen Chen, Yen-Sheng Department of Electronic Engineering National Taipei University of Technology Taipei Taiwan Graduate Institute of Communication Engineering National Taiwan University Taipei Taiwan Department of Communications Navigation and Control Engineering National Taiwan Ocean University Keelung Taiwan Department of Electrical Engineering Ming Chi University of Technology New Taipei City Taiwan

ISBN: (纸本)9781538671023

In this paper., we propose a novel antenna architecture using multiport arrays for 5G base stations. The proposed antenna consists of multiple sub-arrays, performing baseband signal processing so that high gain and broad angular coverage can be achieved simultaneously. The sub-arrays are designed by using series feed networks and patch antenna elements. We arrange these sub-arrays steering to different directions with overlapped sub-array patterns. With the information of the pilot signals., the channel state of each subarray port can be estimated. The output of each sub-array port is combined and fed to a baseband processor, which synthesizes a pattern with high gain and broad angular coverage. The antenna sub-arrays are designed, fabricated, and tested. The system performance utilizing baseband signal processing is also evaluated. Our comparison shows that the proposed antenna overcomes the limitation of conventional array structures. © 2018 IEEE.

关键词： Base stations

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Application of Generalized RBF Network Based on K-means Clustering in Solving Complex Mappings

Application of Generalized RBF Network Based on K-means Clus...

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2018 International Conference on Computer,communication and Network technology(CCNT 2018)

作者： Xun-lai HE Jun-hui YIN Wei-zhao ZHANG Zhen-qian YANG Nantong Institute of Technology Shijiazhuang Campus of Army Engineering University Xi'an Satellite Measurement and Control Center

Initial perturbation is one of the important sources of the distribution of projectile dropping points. However, due to the complex structure of the virtual prototyping system of coupling system, there is no clear functional relationship between the parameters of the initial disturbance index and its influencing parameters. It is difficult to establish scientific mapping relationship. In this paper, for the complex mapping problem of multi-objective optimization of initial perturbation, based on K-means clustering generalized RBF network, the nonlinear mapping relationship between initial disturbance index parameters and its important influence parameters is established. Uniform design is used to establish a virtual shooting test scheme, and a generalized radial basis neural network is used to solve complex mappings between initial disturbance index parameters and important influencing parameters, thereby providing an important basis for initial disturbance optimization.

关键词： K-means Neural network Initial disturbance Uniform design Complex mapping

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Ultra-wideband Dual-layer Magnetic Absorber with Active Impedance Matching

Ultra-wideband Dual-layer Magnetic Absorber with Active Impe...

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Progress in Electromagnetics Research Symposium - Fall (PIERS - FALL)

作者： Wei Hu Haobin Zhang Wenxian Zheng Yongjun Yang Weiwei Gu Daniele Inserra Zhengwu Xu Gui Li Dongliang Zhang Jian Li Yongjun Huang Guangjun Wen School of Information and Communication Engineering University of Electronic Science and Technology of China Chengdu China Science and Technology on Electronic Information Control Laboratory Chengdu China Tsinghua Shenzhen International Graduate School Shenzhen China Yibin Intelligent Information System Institute University of Electronic Science and Technology of China Yibin China

ISBN: (数字)9781728153049

ISBN: (纸本)9781728153056

A novel broadband absorber is designed in this paper, which consists of two layers of magnetic materials and metal reflector. In order to achieve broadband performance, the upper layer and the lower layer magnetic material are designed into periodically cylindrically holes with performance multi-resonance frequency. The simulations showed that an absorption more than 90% for normal incident is obtained in the frequency range from 1.62GHz to 18GHz. The absorber has polarization insensitivity when the incident electromagnetic wave is obliquely with TE/TM polarization, and the absorbing is stable within 0-60 degrees incident. The absorber has potential application in radar system and RCS reduced.

关键词： Magnetic materials Absorption Broadband communication Resonant frequency Contracts Permeability

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Ultra-wideband Active Absorber Based on Multiple Frequency Selective Surface and Magnetic Layers

Ultra-wideband Active Absorber Based on Multiple Frequency S...

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Progress in Electromagnetics Research Symposium - Fall (PIERS - FALL)

作者： Weiwei Gu Haobin Zhang Wenxian Zheng Yongjun Yang Wei Hu Daniele Inserra Zhengwu Xu Gui Li Dongliang Zhang Jian Li Yongjun Huang Guangjun Wen School of Information and Communication Engineering University of Electronic Science and Technology of China Chengdu China Science and Technology on Electronic Information Control Laboratory Chengdu China Tsinghua Shenzhen International Graduate School Shenzhen China Yibin Intelligent Information System Institute University of Electronic Science and Technology of China Yibin China

ISBN: (数字)9781728153049

ISBN: (纸本)9781728153056

In this paper, an ultra-thin UWB absorber is designed by using Non-Foster circuit and Frequency Selective Surface. The absorbing structure consists of Non-Foster matching layer, magnetic material layer with FSS and ground layer. To broaden the absorbing bandwidth, two layers of magnetic materials are shaped by holes. It is verified by simulation that the absorptivity is higher than 80% in 0.15GHz-18GHz when the TM polarized wave is incident. And the thickness of the absorber is about 8mm, which is 1/250 of the operating wavelength. The ultra-thin UWB absorber can be widely used in wireless communication and radar applications.

关键词： Periodic structures Impedance Surface impedance Loading Electromagnetics Integrated circuit modeling Magnetic materials

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Cascade control of SATCOM on the Move (SOTM) Antennas with Jacobian Operator

Cascade Control of SATCOM on the Move (SOTM) Antennas with J...

引用

International Conference on control, Mechatronics and Automation (ICCMA)

作者： Mustafa CELIK Oguz Kaan HANCIOGLU Seta BOGOSYAN Michal BASTL Jan NAJMAN Robert GREPL Control Systems Group PROFEN Communication Technologies & Services Inc. Istanbul Turkey Mechatronics Engineering Department Istanbul Technical University Istanbul Turkey Institute of Solid Mechanics Mechatronics and Biomechanics Brno University of Technology Brno Czech Republic

Increasing demand in SATCOM systems has led to the development of Satcom on the Move (SOTM) antennas. Performance, light weight, low cost, and high data rate are the required parameters in the designing of SOTM antenna. The designer has to make a suitable system with respect to these design parameters. With this aim, this paper proposes a 4 axes antenna capable of 3 axes stabilization to compensate for the disturbance. With adding the position controller, the antenna can point and track the satellite on the mobile platforms. Due to the singularity problem in this type of antenna, the 3 axes stabilized antenna system is used in this paper. The kinematic equations and Jacobian operator are derived for calculation of the necessary axis feedback and look angles. The Jacobian operator with MEMS sensor which is a cost-effective solution. Furthermore, we propose PI-based stabilization for the stabilization controller and PID based pointing for the position controller. To verify the proposed algorithms, different disturbances are applied to the system.

关键词： cascade control feedback Jacobian matrices microsensors PI control position control satellite antennas stability three-term control

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Artificial intelligence enabled radio propagation for communications - Part I: Channel characterization and antenna-channel optimization

arXiv

引用

arXiv 2021年

作者： Huang, Chen He, Ruisi Ai, Bo Molisch, Andreas F. Lau, Buon Kiong Haneda, Katsuyuki Liu, Bo Wang, Cheng-Xiang Yang, Mi Oestges, Claude Zhong, Zhangdui The Purple Mountain Laboratories Nanjing211111 China The National Mobile Communications Research Laboratory School of Information Science and Engineering Southeast University Nanjing210096 China The State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing100044 China The Key Laboratory of Railway Industry of Broadband Mobile Information Communications Beijing Jiaotong University Beijing100044 China The School of Information Engineering Zhengzhou University Zhengzhou450001 China Peng Cheng Laboratory Shenzhen518055 China The Ming Hsieh Department of Electrical and Computer Engineering University of Southern California Los AngelesCA90089 United States The Department of Electrical and Information Technology Lund University Lund22100 Sweden The Department of Radio Science and Engineering Aalto University Aalto00076 Finland The School of Engineering University of Glasgow GlasgowG12 8QQ United Kingdom The Purple Mountain Laboratories Nanjing211111 China The Institute of Information and Communication Technologies Electronics and Applied Mathematics Universite Catholique de Louvain Louvain-la-Neuve 1348 Belgium

To provide higher data rates, as well as better coverage, cost efficiency, security, adaptability, and scalability, the 5G and beyond 5G networks are developed with various artificial intelligence techniques. In this two-part paper, we investigate the application of artificial intelligence (AI) and in particular machine learning (ML) to the study of wireless propagation channels. It firstly provides a comprehensive overview of ML for channel characterization and ML-based antenna-channel optimization in this first part, and then it gives a state-of-the-art literature review of channel scenario identification and channel modeling in Part II. Fundamental results and key concepts of ML for communication networks are presented, and widely used ML methods for channel data processing, propagation channel estimation, and characterization are analyzed and compared. A discussion of challenges and future research directions for ML-enabled next generation networks of the topics covered in this part rounds off the paper. © 2021, CC BY-NC-ND.

关键词： Machine learning

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