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Total ionizing dose effect of gamma rays on H-gate PDSOI MOS devices at different dose rates

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Nuclear Science and Techniques 2017年第10期28卷 51-57页

作者： Qian-Qiong Wang hong-xia Liu Shu-Long Wang chen-Xi Fei Dong-Dong Zhao Shu-Peng chen Wei chen Key Laboratory for Wide Band Gap Semiconductor Materialsand Devices of Education School of MicroelectronicsXidian UniversityXi'an 710071China

The total dose effect of ^(60)Co γ-rays on 0.8μm H-gate partially depleted-silicon-on-insulator NMOS devices was investigated at different irradiation doses. The results show that the shift in saturation current at high dose rate is greater than that at low dose rate, due to increase in interface-state density with decreasing dose rate; the scattering effect of interface state on electrons in the channel causes degradation in carrier mobility; and the body current and transconductance of the back gate enhance low-doserate sensitivity when the irradiation is under OFF-bias. A double transconductance peak is observed at 3 kGy(Si)under high dose rates.

关键词： NMOS器件低剂量率总剂量效应 H型线对 SOI 界面态密度绝缘体上硅

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水平井钻遇储层产能预测测井评价方法

西南石油学院学报 2004年第6期26卷 9-12页

作者：范翔宇夏宏泉陈平闫爽宋帆西南石油学院石油工程学院四川成都610500 塔里木油田勘探开发研究院

储层产能预测是储层评价的重要指标之一。水平井测井解释主要通过常规测井曲线与导眼井常规测井曲线对比校正技术和水平井井眼轨迹与地层穿越关系进行的 ,尽管该方法能给开发工程师提供大量井眼轨迹与地层关系的信息 ,但却很难指出水平... 详细信息

储层产能预测是储层评价的重要指标之一。水平井测井解释主要通过常规测井曲线与导眼井常规测井曲线对比校正技术和水平井井眼轨迹与地层穿越关系进行的 ,尽管该方法能给开发工程师提供大量井眼轨迹与地层关系的信息 ,但却很难指出水平井钻遇储层的生产油气能力如何 ,这为油田开发工作带来了困难。以常规测井资料为基础应用敏感性分析和交会图技术划分井剖面地层 ,得出了储层有效厚度 ;分析试采数据 ,统计出了归一化条件下的水平井日产油量 ,发现二者之间有良好的线性关系 ,继而建立起DS油田XX油组水平井日产油量与储层有效厚度之间的产能预测模型 ,为所研究油组油藏描述工作提供了更为可靠的水平井测井解释结论。

关键词：水平井储层产能预测有效厚度测井评价

Minimum mass-entransy dissipation profile for one-way isothermal diffusive mass-transfer process with mass-resistance and massleakage

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Science China(Technological Sciences) 2024年第8期67卷 2427-2435页

作者： chen LinGen xia ShaoJun Institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan 430205China School of Mechanical Electrical EngineeringWuhan Institute of TechnologyWuhan 430205China School of Power Engineering Naval University of EngineeringWuhan 430033China

As a new concept,mass-entransy is one of the twins in the core of entransy *** can describe mass-transfer ability for masstransfer processes(MTPes),just as thermal-entransy for describing heat-transfer ***,mass-entransy dissipation can be utilized to evaluate the loss of mass-transfer *** mass-entransy dissipation(MMED) is utilized to optimize one-way isothermal diffusive MTPes with mass-leakage and mass-transfer law(g ∝ Δ(c),where c means concentration).For a given net amount of mass-transferred key components at the low-concentration side,optimality-condition for the MMED of isothermal diffusive MTPes is obtained by using the *** of the amount of mass-transferred and mass-leakage on optimal results are analyzed,and the obtained optimization profiles are compared with those for MTP profiles of constant-concentration-difference(c_1-c_2=const) and constant-concentration-ratio(c_1/c_2=const).The product of square of key-component-concentration(KCC) difference between high-and low-concentration sides and inert component concentration at high-concentration side for the MMED of the MTP with no mass-leakage is a constant,and the optimal relationship of the KCCs between high-and low-concentration sides with mass-leakage is significantly different from the *** mass-leakage is relatively small,the MTP with c_1-c_2=const strategy is superior to that with c_1/c_2=const strategy,and the latter is superior to the former with an increase in mass-leakage.A combination of mass-entransy concept,finite-time thermodynamics,and averaged-optimization-method is a meaningful tool for optimizing MTPes.

关键词： diffusive mass-transfer-law mass-leakage one-way isothermal mass-transfer minimum mass-entransy dissipation finite-time thermodynamics averaged-optimization-method

Effects of total dose irradiation on the threshold voltage of H-gate SOI NMOS devices

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Nuclear Science and Techniques 2016年第5期27卷 193-199页

作者： Qian-Qiong Wang hong-xia Liu Shu-Peng chen Shu-Long Wang chen-Xi Fei Dong-Dong Zhao Key Laboratory for Wide Band Gap Semiconductor Materials and Devices of Education School of MicroelectronicsXidian University Xi'an 710071 China

This work researched the impact of total dose irradiation on the threshold voltage of N-type metal oxide semiconductor field effect transistors(nMOSFETs) in silicon-on-insulator(SOI) *** the subthreshold separation technology,the factor causing the threshold voltage shift was divided into two parts:trapped oxide charges and interface states,the effects of which are presented under ***,by analyzing the data,the threshold voltage shows a negative shift at first and then turns to positive shift when irradiation dose is ***,the influence of the dose rate effects on threshold voltage is *** research results show that the threshold voltage shift is more significant in low dose rate conditions,even for a low dose of100 krad(Si).The degeneration value of threshold voltage is 23.4%and 58.0%for the front-gate and the back-gate at the low dose rate,respectively.

关键词：阈值电压漂移总剂量辐照 NMOS器件 SOI 金属氧化物半导体场效应晶体管 H型低剂量率分离技术

Boundary-layer transition prediction using a simplified correlation-based model

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Chinese Journal of Aeronautics 2016年第1期29卷 66-75页

作者： xia chenchao chen Weifang School of Aeronautics and Astronautics Zhejiang University

This paper describes a simplified transition model based on the recently developed correlation-based γ - Reot transition model. The transport equation of transition momentum thick- ness Reynolds number is eliminated for simplicity, and new transition length function and critical Reynolds number correlation are proposed. The new model is implemented into an in-house com- putational fluid dynamics （CFD） code and validated for low and high-speed flow cases, including the zero pressure flat plate, airfoils, hypersonic flat plate and double wedge. Comparisons between the simulation results and experimental data show that the boundary-layer transition phenomena can be reasonably illustrated by the new model, which gives rise to significant improvements over the fully laminar and fully turbulent results. Moreover, the new model has comparable features of accuracy and applicability when compared with the original 3＇ - Reot model. In the meantime, the newly proposed model takes only one transport equation of intermittency factor and requires fewer correlations, which simplifies the original model greatly. Further studies, especially on separation- induced transition flows, are required for the improvement of the new model.

关键词： Boundary-layer transition Computational fluiddynamics Correlation Transition model Turbulence model

Global robust optimal sliding mode control for uncertain affine nonlinear systems

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Journal of Systems Engineering and Electronics 2009年第4期20卷 838-843页

作者： Pang Haiping chen xia Coll. of Automation and Electronic Engineering Qingdao Univ. of Science and Technology Qingdao 266042 P. R. China

The problem of robustifying linear quadratic regulators （LQRs） for a class of uncertain affine nonlinear systems is considered. First, the exact linearization technique is used to transform an uncertain nonlinear system into a linear one and an optimal LQR is designed for the corresponding nominal system. Then, based on the integral sliding mode, a design approach to robustifying the optimal regulator is studied. As a result, the system exhibits global robustness to uncertainties and the ideal sliding mode dynamics is the same as that of the optimal LQR for the nominal system. A global robust optimal sliding mode control （GROSMC） is realized. Finally, a numerical simulation is demonstrated to show the effectiveness and superiority of the proposed algorithm compared with the conventional optimal LQR.

关键词： robust control optimal control sliding mode control nonlinear systems uncertain systems exact linearization.

A hexahedron element formulation with a new multi-resolution analysis

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Science China(Physics,Mechanics & Astronomy) 2015年第1期58卷 65-74页

作者： xia YiMing chen ShaoLin Civil Engineering Department Nanjing University of Aeronautics and Astronautics

A multiresolution hexahedron element is presented with a new multiresolution analysis(MRA)*** MRA framework is formulated out of a mutually nesting displacement subspace sequence,whose basis functions are constructed of scaling and shifting on element domain of a basic node shape *** basic node shape function is constructed from shifting to other seven quadrants around a specific node of a basic isoparametric element in one quadrant and joining the corresponding node shape functions of eight elements at the specific *** MRA endows the proposed element with the resolution level(RL)to adjust structural analysis *** a result,the traditional 8-node hexahedron element is a monoresolution one and also a special case of the proposed *** meshing for the monoresolution finite element model is based on the empiricism while the RL adjusting for the multiresolution is laid on the solid mathematical *** simplicity and clarity of shape function construction with the Kronecker delta property and the rational MRA enable the proposed element method to be more rational,easier and efficient in its implementation than the conventional mono-resolution solid element method or other MRA *** multiresolution hexahedron element method is more adapted to dealing with the accurate computation of structural problems.

关键词： hexahedron element multiresolution analysis (MRA) resolution level (RL) basic node shape function mutually nesting displacement subspace sequence scaling and shifting

Power output and efficiency optimization of endoreversible non-isothermal chemical engine via Lewis analogy

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Science China(Technological Sciences) 2023年第9期66卷 2651-2659页

作者： chen LinGen xia ShaoJun Institute of Thermal Science and Power Engineering Wuhan Institute of TechnologyWuhan 430205China School of Mechanical&Electrical Engineering Wuhan Institute of TechnologyWuhan 430205China School of Power Engineering Naval University of EngineeringWuhan 430033China

Compared with endoreversible heat engine with pure heat transfer and endoreversible isothermal chemical engine with pure mass transfer,endoreversible non-isothermal chemical engine(ENICE)is a more reasonable model of practical mass exchanger,solid device and chemo-electric *** exists heat and mass transfer(HMT)simultaneously between working fluid and chemical potential reservoir in *** is coupled HMT effect that in ENICE should be *** are two ways to consider this coupled *** is based on Onsager equations,and another is based on Lewis *** the mathematical and physical description of the above HMT process,the model using Onsager equations are more appropriate in the linear HMT region not far from the equilibrium state,while that based on Lewis analogy is more appropriate in nonlinear HMT region far from the equilibrium *** from the previous research on the power optimization of ENICEs with Onsager equations,this paper optimizes power and efficiency of ENICE based on Lewis *** processes are assumed to obey Newtonian heat transfer law(q∝ΔT,and T is temperature)and Fick's diffusive mass transfer law(g∝Δc,and c is concentration),*** results of power output and corresponding vector efficiency(η_(T)andη_(μ))of ENICE are obtained,which provide important parallel results with those based on Onsager *** include special cases for endoreversible Carnot heat engine with q∝ΔT and endoreversible isothermal chemical engine with g∝Δ*** Lewis analogy in the modelling of ENICEs with simultaneous HMT is an important *** provides important analytical and numerical results different from those with Onsager equations obtained previously and enriches the research contents of *** research results in this paper have a certain guiding significance for the optimal designs of single irreversible NICEs,multistage NICE systems,practical mass exchangers,solid devices,chemo-electric syste

关键词： finite time thermodynamics endoreversible non-isothermal chemical engine Lewis analogy heat and mass transfer vector efficiency maximum power output

EFFECTS OF TEMPERATURE AND CONCENTRATION ON RHEO-LOGICAL CHARACTERISTICS OF SURFACTANT ADDITIVE SOLUTIONS

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Journal of Hydrodynamics 2008年第5期20卷 603-610页

作者： ZHANG hong-xia WANG De-zhong GU Wei-guo chen Han-ping School of Mechanical Engineering Shanghai Jiao Tong University Shanghai 200240 China

The shear viscosity of turbulent drag-reducing surfactant solution was measured as a function of concentration, shear rate and temperature by using an AG-G2 rheometer （TA Instruments, New Castle, USA）. The experimental results showed complicated rheological behavior with the concentration in large. The Bird-Carreau model was found to fit well to the measured rheological results. The characteristics for the parameters ηo-ηx and λ dependence on temperature were also studied.

关键词： shear viscosity surfactant solution drag reduction Bird-Carreau model AR-G2 rheometer