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A transformer-loaded receiver front end for 2.4 GHz WLAN in 0.13μm CMOS technology

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Journal of Semiconductors 2011年第12期32卷 101-106页

作者：彭苗林敏石寅代伐 Institute of Semiconductors Suzhou-CAS Semiconductors Integrated technology Research center department of electrical & Computer engineering Auburn University

A 2.4 GHz radio frequency receiver front end with an on-chip transformer compliant with IEEE 802.11b/g standards is presented. Based on zero-IF receiver architecture, the front end comprises a variable gain common-source low noise amplifier with an on-chip transformer as its load and a high linear quadrature folded Gilbert mixer. As the load of the LNA, the on-chip transformer is optimized for lowest resistive loss and highest power gain. The whole front end draws 21 mA from 1.2 V supply, and the measured results show a double side band noise figure of 3.75 dB, -31 dBm IIP3 with 44 dB conversion gain at maximum gain setting. Implemented in 0.13 μm CMOS technology, it occupies a 0.612 mm^2 die size.

关键词： zero-IF direct-down-conversion WLAN CMOS RF on-chip transformer

Effect of auxiliary ventilations on diesel particulate matter dispersion inside a dead-end entry

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International Journal of mining Science and technology 2015年第6期25卷 927-932页

作者： Zheng Yi Thiruvengadam Magesh Lan Hai Tien C.Jerry department of mining & Nuclear engineering Missouri University of Science and Technology Clean Air Power Inc. Division of mining and Resources engineering Department of Civil Engineering Monash University

Diesel particulate matter(DPM) is considered carcinogenic after prolonged exposure. This paper used computational fluid dynamics(CFD) method to study the effect of four auxiliary ventilation systems on DPM distribution in a dead-end entry with loading operation. The auxiliary ventilation systems considered include: blower fan and tubing; exhaust fan and tubing, jet fan, and push–pull system. A species transport model with buoyancy effect was used to examine the DPM dispersion pattern with unsteady state analysis. During the 200 s of the loading operation, high DPM levels were identified in the face and dead-end entry regions. This study can be used for mining engineer as guidance to design and setup of local ventilation. It can also be used for selection of DPM control strategies and DPM annual training for underground miners.

关键词： Diesel particulate matterComputational fluid dynamicsAuxiliary ventilationDead-end entry

Equivalent input disturbance-based load frequency control for smart grid with air conditioning loads

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Science China(Information Sciences) 2022年第2期65卷 106-123页

作者： Li JIN Yong HE Chuan-Ke ZHANG Xing-Chen SHANGGUAN Lin JIANG Min WU School of Automation China University of Geosciences Hubei Key Laboratory of advanced Control and Intelligent Automation for Complex Systems department of electrical engineering and Electronics University of Liverpool engineering Research center of Intelligent technology for Geo-Exploration Ministry of Education

Integrating intermittent wind power into power systems results in low or zero inertia, threatening their frequency stability. To accommodate intermittent generations, the demand response(DR) is introduced, and air conditioning loads(ACs) account for an increasing proportion of all loads. The replacement of traditional generators with wind turbines and the ACs user uncertainties produce parameter uncertainties. This paper aims to construct an equivalent input disturbance(EID)-based load frequency control(LFC) strategy for the power system by considering wind power and ACs. First, an open-loop model is constructed for the LFC scheme with parameter uncertainties. Then, the parameter uncertainties and external disturbance are lumped into a fictitious disturbance, which is estimated using an EID *** incorporating the estimation of disturbance into the control input, the disturbance-rejection performance is achieved. Next, the Lyapunov theory is used to derive the two linear-matrix-inequality-based asymptotic stability criteria. A design algorithm is developed for the EID-based LFC scheme by exploiting an overall performance evaluation index. Finally, simulation results for the single-area and two-area LFC schemes show that, compared with the existing approaches, the method presented realizes the better disturbance rejection and higher robustness against parameter uncertainties, wind power fluctuation, and tie-line power ***, its robustness to time delays is verified.

关键词： equivalent input disturbance load frequency control parameter uncertainties wind power air conditioning loads

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On the chronological understanding of the homogeneous dielectric barrier discharge

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High Voltage 2023年第6期8卷 1132-1150页

作者： Xinpei Lu Zhi Fang Dong Dai Tao Shao Feng Liu Cheng Zhang Dawei Liu Lanlan Nie Chunqi Jiang State Key Laboratory of advanced Electromagnetic engineering and technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhanChina College of electrical engineering and Control Science Nanjing Tech TechnologyNanjingChina School of Electric Power South China University of TechnologyGuangzhouChina Institute of electrical engineering Chinese Academy of SciencesBeijingChina Frank Reidy Research center for Bioelectrics Old Dominion UniversityNorfolkVirginiaUSA department of electrical and Computer engineering Old Dominion UniversityNorfolkVirginiaUSA

Dielectric barrier discharges(DBD)are widely utilised non‐equilibrium atmospheric pressure plasmas with a diverse range of applications,such as material processing,surface treatment,light sources,pollution control,and *** the course of several decades,extensive research has been dedicated to the generation of homogeneous DBD(H‐DBD),focussing on understanding the transition from H‐DBD to filamentary DBD and exploring strategies to create and sustain H‐*** paper first discusses the in-fluence of various parameters on DBD,including gas flow,dielectric material,surface conductivity,and mesh ***,a chronological literature review is presented,highlighting the development of H‐DBD and the associated understanding of its un-derlying *** encompasses the generation of H‐DBD in helium,nitrogen,and ***,the paper provides a brief overview of multiple‐current‐pulse(MCP)behaviours in H‐*** objective of this article is to provide a chronological un-derstanding of homogeneous dielectric barrier discharge(DBD).This understanding will aid in the design of new experiments aimed at better comprehending the mechanisms behind H‐DBD generation and ultimately assist in achieving large‐volume H‐DBD in an air environment.

关键词： dielectric barrier pollution

Intelligent Predetermination of Generator Tripping Scheme: Knowledge Fusion-based Deep Reinforcement Learning Framework

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 66-75页

作者： Lingkang Zeng Wei Yao Ze Hu Hang Shuai Zhouping Li Jinyu Wen Shijie Cheng State Key Laboratory of advanced Electromagnetic engineering and technology School of Electrical and Electronics EngineeringHuazhong University of Science and TechnologyWuhan 430074China Dispatching and Control center Central China Branch of State Grid Corporation of ChinaWuhan 430077China. department of electrical engineering and Computer Science University of TennesseeKnoxvilleTN 37996USA

Generator tripping scheme(GTS)is the most commonly used scheme to prevent power systems from losing safety and ***,GTS is composed of offline predetermination and real-time scenario ***,it is extremely time-consuming and labor-intensive for manual predetermination for a large-scale modern power *** improve efficiency of predetermination,this paper proposes a framework of knowledge fusion-based deep reinforcement learning(KF-DRL)for intelligent predetermination of ***,the Markov Decision Process(MDP)for GTS problem is formulated based on transient instability ***,linear action space is developed to reduce dimensionality of action space for multiple controllable ***,KF-DRL leverages domain knowledge about GTS to mask invalid actions during the decision-making *** can enhance the efficiency and learning ***,the graph convolutional network(GCN)is introduced to the policy network for enhanced learning *** simulation results obtained on New England power system demonstrate superiority of the proposed KF-DRL framework for GTS over the purely data-driven DRL method.

关键词： Deep reinforcement learning generator tripping scheme graph convolutional network invalid action masking knowledgefusion

Tunable acoustic radiation pattern assisted by effective impedance boundary

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Chinese Physics B 2016年第2期25卷 215-220页

作者：钱枫全力王力维刘晓宙龚秀芬 Key Laboratory of Modern Acoustics Institute of Acoustics and School of Physics Collaborative Innovation Center of Advanced MicrostructuresNanjing University College of Physics & Electronic engineering Changshu Institute of Technology department of electrical and Computer engineering The University of Texas at Austin

The acoustic wave propagation from a two-dimensional subwavelength slit surrounded by metal plates decorated with Helmholtz resonators （HRs） is investigated both numerically and experimentally in this work. Owing to the presence of HRs, the effective impedance of metal surface boundary can be manipulated. By optimizing the distribution of HRs, the asymmetric effective impedance boundary will be obtained, which contributes to generating tunable acoustic radiation pattern such as directional acoustic beaming. These dipole-like radiation patterns have high radiation efficiency, no finger- print of sidelobes, and a wide tunable range of the radiation pattern directivity angle which can be steered by the spatial displacements of HRs.

关键词： effective impedance boundary acoustic radiation pattern Helmholtz resonator

Robust design of static synchronous series compensator-based stabilizer for damping inter-area oscillations using quadratic mathematical programming

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第4期11卷 296-306页

作者： Mahmoud Reza SHAKARAMI Ahad KAZEMI center of Excellence for Power System Automation and Operation Department of Electrical EngineeringIran University of Science and Technology

This paper presents a procedure for designing a supplementary damping stabilizer for a static synchronous series compensator(SSSC) in multi-machine power *** objective is to shift the lightly damped inter-area modes toward the prescribed stability region.A lead-lag stabilizer is used to demonstrate this technique,in which a particular measure of stabilizer gain is considered as an objective *** of the problem for phase-lead and lag structures are *** objective function with the constraints is formed as a quadratic mathematical programming *** robust design,the parameters of the stabilizer are calculated under various operating *** types of SSSC-based stabilizer have been presented and *** results including eigenvalue analysis and the nonlinear simulations on the 4-and 50-machine power systems are pre-sented to show the effectiveness of the proposed method.

关键词： Inter-area oscillations Static synchronous series compensator(SSSC) Damping stabilizer Robust design Quadratic mathematical programming

Evolution Handoff Strategy for Real-Time Video Transmission over Practical Cognitive Radio Networks

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China Communications 2015年第2期12卷 141-154页

作者： LIU Fa MA Yongkui ZHAO Honglin DING Kai Communication Research center Harbin Institute of Technology department of electrical engineering and Computer Science University of California

The transmission delay of realtime video packet mainly depends on the sensing time delay(short-term factor) and the entire frame transmission delay(long-term factor).Therefore,the optimization problem in the spectrum handoff process should be formulated as the combination of microscopic optimization and macroscopic *** this paper,we focus on the issue of combining these two optimization models,and propose a novel Evolution Spectrum Handoff(ESH)strategy to minimize the expected transmission delay of real-time video *** the microoptimized model,considering the tradeoff between Primary User's(PU's) allowable collision percentage of each channel and transmission delay of video packet,we propose a mixed integer non-linear programming *** scheme is able to achieve the minimum sensing time which is termed as an optimal stopping *** the macro-optimized model,using the optimal stopping time as reward function within the partially observable Markov decision process framework,the EHS strategy is designed to search an optimal target channel set and minimize the expected delay of packet in the long-term real-time video ***,the minimum expected transmission delay is obtained under practical cognitive radio networks' conditions,i.e.,secondary user's mobility,PU's random access,imperfect sensing information,etc..Theoretical analysis and simulation results show that the ESH strategy can effectively reduce the transmission delay of video packet in spectrum handoff process.

关键词： practical cognitive radio networks spectrum handoff process partially observable Markov decision process video transmission

Graphene electrode with tunable charge transport in thin-film transistors

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Nano Research 2018年第1期11卷 274-286页

作者： Ick-Joon Park Tae In Kim In-Tak Cho Chang-Woo Song Ji-Woong Yang Hongkeun Park Woo-Seok Cheong Sung Gap Im Jong-Ho Lee Sung-Yool Choi School of electrical engineering GrapheneY2D Materials Research Center Korea Advanced Institute of Science and Technology (KAIST) Daejeon 34141 Republic of Korea department of electrical engineering Seoul National University Seou108826 Republic of Korea Electronics and Telecommunications Research Institute Daejeon 34129 Republic of Korea department of Chemical and Biomolecular engineering Graphene/2D Materials Research Center Korea Advanced Institute of Science and Technology (KAIST) Daejeon 34141 Republic of Korea

Graphene, a single atomic layer of sp2-hybridized carbon, has immense potential as a transparent conducting material in electronic applications owing to its superior properties, including optical transparency and high conductivity. Particularly, the tunable work function of graphene enables the integration of graphene electrodes with various electronic devices. To achieve high performance in graphene-based devices, effective charge transport between the graphene electrode and the semiconducting material needs to be optimized; this is closely related to the modulation of the Schottky barrier （SB）. In this study, we investigate the ~nable charge transport properties as a function of graphene doping in n-channel thin-film transistors （TFTs） in terms of the electrical characteristics and low-frequency noise （LFN） behaviors. Alkali metal carbonates tuned the work function of graphene, resulting in a dramatic decrease in the SB and an improvement of the carrier injection in n-channel TFTs. The electrical performance of the TFTs was evaluated by extraction of the field-effect mobilities and ratio of contact resistance to total resistance. Furthermore, the level of contact noise created by the barrier height fluctuation and relative contribution of channel noise and contact noise in the TFTs was investigated by LFN measurements to demonstrate the ~nable charge transport. Our findings therefore provide new insights into the tunable charge transport mechanism in graphene-based devices and reveal the immense potential of graphene as electrodes in high performance flexible and transparent displays.

关键词： charge transport graphene doping Schottky barrier work function contact property low-frequency noise