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An experiment of automatic PMD compensation in 40-Gb/s RZ optical communication system

激光与光电子学进展 2004年第5期2卷 262-264页

作者：席丽霞张晓光于丽周光涛张宏明张娜张建忠吴斌苑铁成姚敏玉杨伯君 Department of Physics School of Science Beijing University of Posts and Telecommunications Beijing 100876 Department of Electronic Engineering Tsinghua University Beijing 100084

An experiment of adaptive polarization mode dispersion (PMD) compensation for 40-Gb/s return-to-zero (RZ) optical communication system is reported. In the experiment, degree of polarization (DOP) is used as feedback signal and particle swarm optimization (PSO) method is adopted as logic control *** compensation time is about 200 ms, the compensated differential group delay (DGD) is up to 30 ps,and bit error rate (BER) of 10-9 is reached when PMD compensation is employed.

关键词： PMD compensation polarization mode dispersion particle swarm optimization differential group delay communication system control algorithm bit error rate

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A Horizontality Adjusting Study of the Earth Drill′s Platform

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International Journal of Plant Engineering and Management 2005年第2期10卷 77-81页

作者： HUChang-sheng ZHAOWei-min LIGui-xian FANJia-kun ShiWenjie SchoolofMechtronics HarbinIstituteofTechnologyHarbin150006P.R.China SchoolofMechtronics DaqingPetroleumUniversityDaqing163000P.R.China

A horizontality adjusting system of the earth drill's platform is designed todeal with the operation difficulty of the platform which appeared while the earth drill is *** proportional-impulse control to eliminate the over-adjustment andelectricity-hydraulic-proportional control to drive the adjusting mechanism are adopted in thesystem. The control scheme and control algorithm are introduced in detail. The software flow chartis given.

关键词： earth drill control algorithm horizontality adjustment of platform electricity-hydraulic-proportional control proportional- impulse control

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An optimal algorithm to assess the compliance with the T 2s requirement of Waste-to-Energy facilities

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Energy Procedia 2017年 120卷 317-324页

作者： Federico Viganò Francesco Magli Department of Energy – Politecnico di Milano Via R. Lambruschini 4/A Milan 20156 Italy Consorzio LEAP Via N. Bixio 27/C Piacenza 29121 Italy MatER (Materials and Energy from Refuse) Research Center c/o Consorzio LEAP

The gas resulting from the incineration of waste must be raised, after the last injection of combustion air, in a controlled and homogeneous fashion and even under the most unfavorable conditions, to a temperature of at least 850 °C for at least two seconds (Art. 50.2 Directive 2010/75/EU). This norm and its variations (i.e. 1,100 °C for 2 s if the chlorine content of the incinerated waste exceeds 1% by mass), called “T 2s requirement”, oblige all Waste-to-Energy (WtE) plant operators to monitor the post-combustion conditions and to turn on auxiliary burners in the occurrence of noncompliance with such a requirement. In a WtE boiler, the determination of the mean temperature reached by combustion gas in the post-combustion zone, after an ideal residence time of 2 s, is carried out by an algorithm implemented in the Distributed control System (DCS) of the plant. Currently, since many different algorithms are used, it appears that further investigation on this subject is required. This work considers, as a case study, an existing WtE boiler and, by means of a calibrated long-furnace model of the post-combustion zone, investigates all the possible operating conditions as well as their connections with the monitored variables. The most relevant influences on the T 2s temperature are highlighted and some control algorithms are proposed. The results so far obtained show that the T 2s is affected both by boiler load and gas-side fouling in the same way and for the same extent. Therefore, since gas-side fouling in the post-combustion zone is an uncontrollable variable, boiler load is not usable in as input variable of a reliable algorithm. Moreover, the results highlight the significant role that can be played in the algorithm for the estimation of the T 2s by the oxygen content in secondary flue gas.

关键词： Waste-to-Energy T 2s requirement temperature after two seconds suction pyrometer boiler model control algorithm

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Adaptive Bolus Chasing Computed Tomography Angiography

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IFAC Proceedings Volumes 2008年第2期41卷 6648-6653页

作者： Er-Wei Bai Zhijun Cai Ge Wang Electrical and Computer Engineering The University of Iowa Iowa City IA 52242 USA VT-WFU School of Biomedical Eng. & Sci. Virginia Polytechnic Institute & State University Blacksburg VA 24061 USA

Synchronization of the contrast bolus peak and CT imaging aperture is a crucial issue for CTA. It effects the CTA imaging quality and the necessary amount of contrast dose. In this paper, we propose an optimal adaptive bolus chasing controller. The controller estimates and predicts the unknown two dimensional bolus density on line and then determines the optimal control actions. Tracking errors are mathematically quantified in terms of estimation errors. Simulation results on the actual patient data exhibit its superior performance to the current constant-speed method. Also, the preliminary experiments demonstrate the clinical feasibility.

关键词： adaptive control optimal control control algorithm medical systems Computed Tomography (CT) CT Angiography (CTA)

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Fault tolerant single-phase capacitor start capacitor run induction motor powered with cascaded multilevel quasi impedance source inverter

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JOURNAL OF ENGINEERING-JOE 2019年第17期2019卷 4036-4040页

作者： Rahman, Syed Meraj, Mohammad Iqbal, Atif Ben-Brahim, Lazhar Alammari, Rashid Abu-Rub, Haitham Qatar Univ Dept Elect Engn Doha Qatar Texas A&M Univ Dept Elect & Comp Engn Doha Qatar

In this study, the performance of fault tolerant single-phase capacitor start capacitor run induction motor powered using seven-level quasi-impedance source inverter (qZSI) is analysed. The seven-level inverter consists of three units of qZSI connected in cascade. When one of the qZSI module fails (due to semiconductor failure), the resultant rms voltage applied to the motor will be reduced by one-third. This leads to reduction in both mechanical speed and electromagnetic torque of the motor. To restore the performance of the motor to pre-fault condition, the voltage deficit must be compensated. In conventional CHB inverter, it is not possible to achieve the pre-fault voltage. However, in qZSI, it is possible to achieve required voltage boost by application of shoot through duty cycle. Here, voltage of other two healthy operating modules can be boosted to reach pre-fault inverter output voltage during post-fault condition. The maximum voltage boost achievable is limited by the maximum shoot-through duty cycle which is related with modulation index. To verify the concept, simulation results of single-phase capacitor-start capacitor-run induction motor with or without proposed control algorithm are discussed. Experimental results for the proposed algorithm with RL load are discussed.

关键词： machine control starting torque invertors fault tolerance induction motors velocity load (electric) electric impedance qZSI module pre-fault condition fault tolerant single-phase capacitor start capacitor run induction motor CHB inverter cascaded multilevel quasi impedance source inverter RL load control algorithm modulation index maximum shoot-through duty cycle rms voltage boost electromagnetic torque mechanical speed

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Machine vision-based autonomous road hazard avoidance system for self-driving vehicles

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SCIENTIFIC REPORTS 2024年第1期14卷 1-15页

作者： Qiu, Chengqun Tang, Hao Yang, Yuchen Wan, Xinshan Xu, Xixi Lin, Shengqiang Lin, Ziheng Meng, Mingyu Zha, Changli Yancheng Inst Technol Sch Automot Engn Yancheng 224051 Peoples R China Yancheng Teachers Univ Jiangsu Prov Intelligent Optoelect Devices & Measu Yancheng 224007 Peoples R China Hefei Univ Technol Sch Automot & Transportat Engn Hefei 230009 Anhui Peoples R China Tokyo Inst Technol Interdisciplinary Grad Sch Sci & Engn Yokohama 2268502 Japan Anqing Normal Univ Sch Elect Engn & Intelligent Mfg Anqing 246133 Anhui Peoples R China

The resolution of traffic congestion and personal safety issues holds paramount importance for human's life. The ability of an autonomous driving system to navigate complex road conditions is crucial. Deep learning has greatly facilitated machine vision perception in autonomous driving. Aiming at the problem of small target detection in traditional YOLOv5s, this paper proposes an optimized target detection algorithm. The C3 module on the algorithm's backbone is upgraded to the CBAMC3 module, introducing a novel GELU activation function and EfficiCIoU loss function, which accelerate convergence on position loss l box , confidence loss l obj , and classification loss l cls , enhance image learning capabilities and address the issue of inaccurate detection of small targets by improving the algorithm. Testing with a vehicle-mounted camera on a predefined route effectively identifies road vehicles and analyzes depth position information. The avoidance model, combined with Pure Pursuit and MPC control algorithms, exhibits more stable variations in vehicle speed, front-wheel steering angle, lateral acceleration, etc., compared to the non-optimized version. The robustness of the driving system's visual avoidance functionality is enhanced, further ameliorating congestion issues and ensuring personal safety.

关键词： Deep learning Machine vision Self-Driving Risk avoidance YOLOv5s control algorithm

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The Structure and algorithm for controlling the Shut-off Valves of a Multi-section Mobile Car Gas Refueler

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Procedia Computer Science 2018年 145卷 656-660页

作者： Andrew A. Evstifeev Margarita A. Zaeva National Research Nuclear University MEPhI (Moscow Engineering Physics Institute) Kashirskoe shosse 31 Moscow 115409 Russia LLC Gazprom VNIIGAZ Leninsky district Razvilkovsky village Razvilka 5537 Proyektiruyemyy Proyezd 15-1 Moscow region 142717 Russia

An embodiment of the structure and control algorithm of the isolation valve of multi-section mobile car refueling. It is shown that this option provides the most energy efficient and rational option for refueling consumers. The calculation of the most rational pressure, number and volume of sections is performed. The algorithm of control is based on the modified algorithm of multicriteria selection of the Edgeworth-Pareto.

关键词： control algorithm multicriteria selection Edgeworth-Pareto multi-section mobile car refueling

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A Genetic algorithm-Enhanced Sensor Marks Selection algorithm for Wavefront Aberration Modeling in Extreme-UV (EUV) Photolithography

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INFORMATION 2023年第8期14卷 428页

作者： Magklaras, Aris Alefragis, Panayiotis Gogos, Christos Valouxis, Christos Birbas, Alexios ASML NL-5504 DR Veldhoven Netherlands Univ Patras Dept Elect & Comp Engn Patras 26504 Greece Univ Peloponnese Dept Elect & Comp Engn Patras 26334 Greece Univ Ioannina Dept Informat & Telecommun Arta 47100 Greece

In photolithographic processes, nanometer-level-precision wavefront-aberration models enable the machine to be able to meet the overlay (OVL) drift and critical dimension (CD) specifications. Software control algorithms take as input these models and correct any expected wavefront imperfections before reaching the wafer. In such way, a near-optimal image is exposed on the wafer surface. Optimizing the parameters of these models, however, involves several time costly sensor measurements which reduce the throughput performance of the machine in terms of exposed wafers per hour. In that case, photolithography machines come across the trade-off between throughput and quality. Therefore, one of the most common optimal experimental design (OED) problems in photolithography machines (and not only) is how to choose the minimum amount of sensor measurements that will provide the maximum amount of information. Additionally, each sensor measurement corresponds to a point on the wafer surface and therefore we must measure uniformly around the wafer surface as well. In order to solve this problem, we propose a sensor mark selection algorithm which exploits genetic algorithms. The proposed solution first selects a pool of points that qualify as candidates to be selected in order to meet the uniformity constraint. Then, the point that provides the maximum amount of information, quantified by the Fisher-based criteria of G-, D-, and A-optimality, is selected and added to the measurement scheme. This process, however, is considered "greedy", and for this reason, genetic algorithms (GA) are exploited to further improve the solution. By repeating in parallel the "greedy" part several times, we obtain an initial population that will be the input to our GA. This meta-heuristic approach outperforms the "greedy" approach significantly. The proposed solution is applied in a real life semiconductors industry use case and achieves interesting industry as well as academical results.

关键词： photolithography optimal design of experiments optimal experimental design G-optimal D-optimal A-optimal control algorithm optimization genetic algorithms compound criteria

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A Novel Energy-regenerative Active Suspension for Vehicles

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Journal of Shanghai Jiaotong university(Science) 2008年第2期13卷 184-188页

作者：郑雪春喻凡张勇超 State Key Laboratory of Mechanical System and Vibration Institute of Automotive EngineeringShanghai Jiaotong University

In order to regenerate electric power from the vibration excited by road unevenness,a novel energy- regenerative active suspension for vehicles was proposed with the description of its structure and its working principle with two modes switched in different operating ***,the novel active system was modeled and simulated to show the performance improvement in ride comfort in its electrical motor ***,the performance tests of the actuator prototype were carried out,which proves its capability for damping in its regenerative braking *** research results can provide useful guidance for the similar electrical active suspension design and development.

关键词： active suspension control algorithm energy regeneration vehicle dynamics

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Efficiency loss breakdown for synchronous rectification scheme for automotive applications

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JOURNAL OF ENGINEERING-JOE 2019年第17期2019卷 3715-3719页

作者： Sarafianos, Dimitrios Llano, Danilo X. McMahon, Richard Flack, Timothy Pickering, Stephen Univ Cambridge Elect Engn Div Cambridge CB3 0FA England Univ Warwick WMG Coventry CV4 7AL W Midlands England JaguarLandRover Ltd Coventry W Midlands England

This article presents a synchronous rectification scheme using a six-phase Lundell alternator and a bespoke MOSFET-based active rectifier. The control of the alternator-rectifier system is divided into the hysteresis DC-link voltage control and the switching pattern algorithm. The first allows to keep the DC-link voltage at the required 14V level, while the latter reproduces the same switching pattern as that of a passive rectifier. The system is tested at three different speeds and the results are compared against the body diodes of the MOSFETs in the active rectifier. The harmonic analysis of the generated waveforms indicates the capability of the control algorithm to generate the same switching pattern of a passive rectifier. Finally, the efficiency measurements illustrate a significant efficiency improvement using a synchronous rectification scheme and MOSFETs with low on-resistance.

关键词： rectifiers rectifying circuits alternators rectification semiconductor diodes voltage control harmonic analysis DC-DC power convertors automotive electronics MOSFET hysteresis DC-link voltage control switching pattern algorithm required 14V level passive rectifier control algorithm synchronous rectification scheme efficiency loss breakdown automotive applications six-phase Lundell alternator bespoke MOSFET-based active rectifier alternator-rectifier system voltage 14 0 V

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