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An Integrated Approach to Hypersonic Entry Attitude Control

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International Journal of Automation and computing 2014年第1期11卷 39-50页

作者： Zhi-Qiang Pu ru-yi Yuan Xiang-Min Tan Jian-Qiang yi Institute of Automation Chinese Academy of Sciences

This paper presents an integrated approach based on dynamic inversion(DI)and active disturbance rejection control(ADRC)to the entry attitude control of a generic hypersonic vehicle(GHV).DI is frstly used to cancel the nonlinearities of the GHV entry model to construct a basic attitude *** enhance the control performance and system robustness to inevitable disturbances,ADRC techniques,including the arranged transient process(ATP),nonlinear feedback(NF),and most importantly the extended state observer(ESO),are integrated with the basic DI *** one primary task,the stability and estimation error of the second-order nonlinear ESO are analyzed from a brand new perspective:the nonlinear ESO is treated as a specifc form of forced Li′enard *** qualitative properties of the Li′enard system are utilized to yield comprehensive theorems on nonlinear ESO solution behaviors,such as the boundedness,convergence,and existence of periodic *** portraits of ESO estimation error dynamics are given to validate our *** last,three groups of simulations,including comparative simulations with modeling errors,Monte Carlo runs with parametric uncertainties,and a six degrees-of-freedom reference entry trajectory tracking are executed,which demonstrate the superiority of the proposed integrated controller over the basic DI controller.

关键词： Hypersonic vehicle attitude control dynamic inversion active disturbance rejection control stability analysis

High-level theoretical study of the evolution of abundances and interconversion of glycine conformers

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Chinese Physics B 2018年第4期27卷 264-271页

作者： Fan Liu Jing Yu Yan-ru huang College of Science Liaoning Shihua University Fushun 113001 China

The relative conformer energies of glycine are evaluated by using a focal point analysis expressed as（HF→MP2→MP3→CCSD→CCSD（T））.The conformer abundances at various temperatures（298–500 K） are calculated based on the relative energies and Boltzmann statistical thermostatistical analysis with and without considering internal hindered rotations.A comparison between the available Raman spectrum and the electron momentum spectrum confirms that the influence of rigid-rotor hindered rotation on the conformational proportions of glycine is considerable,especially for the IIIp *** conformational interconversions are *** is found that with increasing temperature,the mole fraction of IIn keeps constant and Ip structure can convert into IVn and IIIp,leading to the decrease in the weight of Ip and the increase in the weights of IVn and IIIp conformers,which is in accordance with experimental observations.

关键词： glycine conformation abundance interconversion

Extra-Large Magnetoresistance in Fe/In2O3 Granular Films

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Chinese Physics Letters 2002年第7期19卷 1004-1006页

作者： huang Bao-Xin Liu yi-Hua Wang Jun-Hua Zhang Lin Zhang ru-Zhen Zhang Lian-Sheng Mei Liang-Mo Department of Physics and State Key Laboratory of Crystal Materials Shandong University Ji'nan 250100

Nanogranular Fe0.35/(In2O3)0.65 films with complex magnetic structure were prepared by the rf sputtering method. An extra-large magnetoresistance up to 506% was obtained at 2.2K, which is two orders of magnitude larger than that obtained at room temperature. This is related to the interaction with the impurities influencing the local magnetization, which is quite different from the spin-dependent tunnelling effect at room temperature. The interspacing Fe atoms dispersed in the In2O3 matrix play an important role in the transportation properties of carriers at low temperature.

关键词： Indium compounds

Inverted V-shaped evolution of superconducting temperature in SrBC under pressure

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Chinese Physics B 2021年第7期30卷 413-419页

作者： ru-yi Zhao Xun-Wang Yan Miao Gao Department of Physics School of Physical Science and TechnologyNingbo UniversityNingbo 315211China College of Physics and Engineering Qufu Normal UniversityQufu 273165China

Based on density functional first-principles calculations and anisotropic Eliashberg equations,we have investigated the electronic structure,lattice dynamics,and phonon-mediated superconductivity in newly synthesized layered compound Sr BC under *** from Li BC and Mg B2,our calculations surprisingly reveal that Sr BC is isotropic in compressibility,due to the accumulation of substantial electrons in the interstitial *** find that the Sr phonons strongly couple with B-2 pz orbital and the interstitial states,giving rise to a two-gap superconductivity in Sr BC,whose transition temperature shows an inverted V-shaped dependence on *** maximal transition temperature is about 22 K at50 *** both sides of 50 GPa,the transition temperature exhibits quasi-linear variation with positive and negative slopes,*** a variation of transition temperature is infrequent among phonon-mediated *** competition between enhanced electron–phonon matrix element and hardened phonons plays an essential role in governing the behavior of the critical temperature.

关键词： SrBC phonon-mediated superconductivity anisotropic Eliashberg theory first-principles calculation maximally localized Wannier functions

Effect of the yaw angle on turbulent flow structures around the submarine model

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Journal of Hydrodynamics 2024年第3期36卷 421-434页

作者： yi-jing Hu yi Qu Qin Wu Biao huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China Beijing Institute of Electronic System Engineering Beijing100854China

The objective of this paper is to investigate the turbulent flow structures around the submarine model and evaluate the effect of the yaw angle on the turbulent flow *** large eddy simulation based on the boundary data immersion method is used to *** computational domain consists of 1.2×10^(8)uniformly distributed Cartesian orthogonal grid nodes to capture the basic flow characteristics around the *** pressure coefficient,friction coefficient and wake velocity distribution are in good agreement with the experimental *** different types of vortex structures were mainly captured around the model,including horseshoe vortex,sail tip vortex and crossflow separation *** the increase of the yaw angle,the asymmetry of the horseshoe vortex and the tip vortex gradually increases,and the vortex strength of the vortex leg on the windward of the horseshoe vortex and the vortex strength of the tip vortex also increase *** the crossflow separation vortex,the flow separation zone gradually expands and migrates downstream with the increase of the yaw angle.

关键词： Vortex structure submarine model boundary data immersion method yaw angle

Impacts of short-channel effects on the random threshold voltage variation in nanoscale transistors

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Science China(Information Sciences) 2013年第6期56卷 153-159页

作者： WANG runSheng YU Tao huang ru WANG YangYuan Institute of Microelectronics Peking University

In this paper,the impacts of device short-channel effects(SCEs) on the random threshold voltage(V TH) variation in nanoscale bulk MOSFETs are ***,the direct relationship between SCEs and random variations are *** adopting the electrostatic integrity(EI) as the index for SCEs,clear correlations of device SCEs with random V TH variations are observed,which indicate that the random variations can be reduced by simply improving the SCEs in MOS devices with the same channel *** addition,the random dopant fluctuation(RDF) induced σ Vth has a linear relationship with EI and channel ***,considering the contribution of SCEs on RDF modeling,a new normalization method of X VT plot is proposed,which provides a physical way to analyze random V TH variation in nanoscale MOSFETs with different process/device parameters(i.e.,with different electrostatic designs).

关键词： MOSFET short-channel effects(SCEs) random variation random dopant fluctuation(RDF) variability electrostatic integrity

Predictive model-aided filtering scheme of data-collection in WSN

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The Journal of China Universities of Posts and Telecommunications 2011年第2期18卷 17-24页

作者： huang ru ZHANG Zai-chen XU Guang-hui School of Information Science and Engineering East China University of Science and Technology Shanghai 200237 China State Key Laboratory of Mobile Communications Southeast University Nanjing 210096 China Institute of Communications Engineering PLA University of Science and Technology Nanjing 210007 China

The paper proposes a prediction-mode-based filtering mechanism（PMF） to solve the problems of transmission energy wasting caused by time-redundant data in wireless sensor networks（WSN）,according to the characteristic of spatio-temporal correlations on sampling series in *** works have suggested several approaches to decrease energy cost during data transmission process via data aggregation tree *** from those methods in above researches,our proposed scheme mainly focus on reducing the temporal redundant degree in event-source to achieve energy-saving effect via self-adaptive filtering *** framework of PMF for energy-efficient collection is composed of prediction module for mining the change law of time domain,self-learning module for updating model,and driving module for controlling data filtering *** with the design of error driving rule and threshold distributing rule,which is the middleware in the above filtering mechanism,the quantity of transmission load in networks can be greatly inhibited on the premise of quality of service（QoS） assurance and energy consumption can be reduced ***,the experimental results show that the performance of PMF can significantly outperform some classical data-collection algorithms on energy-saving effect and self-adaptability.

关键词： WSN data-collection filtering mechanism energy-saving

Incidence of surgical site infection in minimally invasive colorectal surgery

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World Journal of Gastrointestinal Surgery 2024年第4期16卷 1121-1129页

作者： Lu-Ting Ni ru Zhao yi-ru Ye yi-Ming Ouyang Xin Chen Department of Surgery The First Affiliated Hospital of Soochow UniversitySuzhou 215000Jiangsu ProvinceChina

BACKGROUND Surgical site infection(SSI)is a common complication of colorectal *** invasive surgery notably reduces the incidence of *** study aimed to compare the incidences of SSI after robot-assisted colorectal surgery(RACS)vs that after laparoscopic assisted colorectal surgery(LACS)and to analyze associated risk factors for SSI in minimally invasive colorectal *** To compare the incidences of SSI after RACS and LACS,and to analyze the risk factors associated with SSI after minimally invasive colorectal *** Clinical data derived from patients who underwent minimally invasive colorectal surgery between October 2020 and October 2022 at the First Affiliated Hospital of Soochow University were *** in clinical characteristics and surgeryrelated information associated with RACS and LACS were compared,and possible risk factors for SSI were *** A total of 246 patients(112 LACS and 134 RACS)were included in the ***(17.5%)developed *** proportions of patients who developed SSI were similar in the two groups(17.9%vs 17.2%,P=0.887).Diabetes mellitus,intraoperative blood loss≥100 mL,and incision length were independent risk factors for *** additional risk factors included neoadjuvant therapy,lesion site,and operation *** There was no difference in SSI incidence in the RACS and LACS *** mellitus,intraoperative blood loss≥100 mL,and incision length were independent risk factors for postoperative SSI.

关键词： Colorectal surgery Minimally invasive surgery Surgical site infection

Deep insight into the voltage amplification effect from ferroelectric negative capacitance

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Science China(Information Sciences) 2019年第8期62卷 216-218页

作者： Huimin WANG Qianqian huang Mengxuan YANG Xing ZHANG ru huang Key Laboratory of Microelectronic Devices and Circuits (MOE) Institute of Microelectronics

Dear editor,Power dissipation has become one of the most serious problems for nano-electronics. For conventional transistors, the operation voltage cannot be continuously reduced due to the fundamental limitation of subthreshold swing (SS)(60 mV/decade at room temperature)[1, 2]. The voltage amplification (VA) induced by the negative capacitance

关键词： Deep insight into the voltage amplification effect from ferroelectric negative capacitance