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Data-driven nonlinear control of a solid oxide fuel cell system

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Journal of Central South University 2012年第7期19卷 1892-1901页

作者：李益国沈炯 k.y.lee 刘西陲费文哲 key Laboratory of Energy Thermal Conversion and Control of Ministry of Education(School of Energy and Environment Southeast University) Department of Electrical and Computer Engineering Baylor UniversityWacoTX 76798-7356USA

Solid oxide fuel cells (SOFCs) are considered to be one of the most important clean,distributed resources. However,SOFCs present a challenging control problem owing to their slow dynamics,nonlinearity and tight operating constraints. A novel data-driven nonlinear control strategy was proposed to solve the SOFC control problem by combining a virtual reference feedback tuning (VRFT) method and support vector machine. In order to fulfill the requirement for fuel utilization and control constraints,a dynamic constraints unit and an anti-windup scheme were adopted. In addition,a feedforward loop was designed to deal with the current disturbance. Detailed simulations demonstrate that the fast response of fuel flow for the current demand disturbance and zero steady error of the output voltage are both achieved. Meanwhile,fuel utilization is kept almost within the safe region.

关键词： solid oxide fuel cell (SOFC) data-driven method virtual reference feedback tuning (VRFT) support vector machine(SVM) anti-windup

The effect of the magnetic fields from three different configurations of the MRIgRT systems on the dose deposition from lateral opposing photon beams in a laryngeal geometry–A Monte Carlo study

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Radiation Medicine and Protection 2021年第3期2卷 103-111页

作者： Vivien W.S.Chu Monica W.k.kan Louis k.y.lee kenneth C.W.Wong Macy Tong Anthony T.C.Chan Department of Clinical Oncology Prince of Wales HospitalHong KongChina Department of Clinical Oncology The Chinese University of Hong KongHong KongChina Medical Center The Chinese University of Hong KongChina State key Laboratory of Translational Oncology Sir YK Pao Center for CancerDepartment of Clinical OncologyHong Kong Cancer Institute and Prince of Wales HospitalThe Chinese University of Hong KongHong KongChina

Objective:To investigate the impact of different magnetic field strengths and orientations on the dose deposition from lateral opposing photon beams irradiating a laryngeal geometry,with particular attention focused on the dose homogeneity of the area around the air cavity inside the ***:Geant4 simulation toolkit was used to perform Monte Carlo simulations on a phantom resembling the *** energy spectrum of a 6 MV photon beam from a Varian Clinac iX machine was used to provide the source of *** configurations of the Magnetic Resonance Image-Guided Radiation Therapy(MRIgRT)system were simulated:the Fixed Cylindrical(FC)geometry,the Longitudinal Rotating Biplanar(LRBP)geometry,and the Transverse Rotating Biplanar(TRBP)*** magnetic fields of different field strengths were *** relative dose maps and the homogeneity index(HI)were obtained for ***:The LRBP geometry together with a magnetic field strength of 0.5 T produced the most homogeneous dose distribution with a HI of 0.139 for the region of interest around the air cavity,compared with a HI of 0.180 when the magnetic field was *** TRBP geometry,the dose distribution shifted towards the cranial direction,leading to a region of hot spots at the superior edge and a region of cold spots at the inferior edge of the irradiated *** HI around the air cavity was therefore *** addition,strong electron streaming effect(ESE)was *** the FC geometry,hot and cold spots were formed around the air cavity which increased the ***:Out of the three configurations of the MRIgRT systems,the LRBP geometry produced the most clinically beneficial dose distribution in which it provided a higher dose to the treatment area and a boost in dose to the tissue immediately adjacent to the air cavity.

关键词： Monte Carlo MRIgRT MR-Linac Magnetic field Air cavity

比较胸片、胸部数字体层合成及低剂量MDCT检测肺磨玻璃样小结节:拟人胸部模型研究

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国际医学放射学杂志 2015年第1期 101-101页

作者： k.W.Doo E.y.kang H.S.yong S.y.Ham k.y.lee J.y.Choo Department of Radiology Korea University Guro HospitalKorea University College of Medicine

目的旨在使用拟人胸部模型评估胸片(CXR)、胸部的数字体层合成(DT)和低剂量多层CT(LDCT)检测肺磨玻璃(GGO)小结节的诊断性能。方法人工肺结节被放置于

关键词：胸部躯干胸片低剂量小结节体层

以CT作参照比较数字X线断层影像和胸片在评估气道病变方面的诊断效能

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国际医学放射学杂志 2016年第6期 703-703页

作者： J.y.Choo k.y.lee Ami yu J.H.kim S.H.lee J.W.Choi 郑文松 Department of Radiology Korea University Ansan HospitalKorea University College of Medicine

摘要目的以CT作参照比较数字X线断层影像(DTS)和胸片在评估气道异常方面的诊断效能。方法评价了149例病人的161个数据资料(91个有气道异常,70个无气道异

关键词：胸片 DTS 断层影像诊断效能气道病变 CT

A G^E/Equation of State Mixing Rule for Vapor-Liquid Equilibria

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Chinese Journal of Chemical Engineering 1998年第3期6卷 14-28页

作者：屈一新汪文川 lee y.y. Chung k.y. lee y.W. korea Institute of Science and Technology SeoulKorea

A new excess Gibbs free energy/equation of state type mixing 0rule was derived byremoving the infinite pressure boundary condition imposed by Wong and *** mixing rulewas extensively tested in terms of a comprehensive data base,consisting of 52 simple nonpolar-nonpolar,carbon dioxide containing,hydrocarbon-hydrocarbon,CFC,polar-polar,nonpolar-polarbinary and multicomponent *** on the complete predictive capability,a comparisonbetween the Wong-Sandler and the mixing rule proposed was *** results indicate that thenew mixing rule is in general superior to the Wong-Sandler’s,and the binary interaction parameteras required by the latter is removed,which reduces computing effort and is reliable in predictions ofvapor-liquid equilibria from low pressures to high pressures.

关键词： vapor-liquid equilibria equation of state mixing rule

Effect of Thermal Refining on Mechanical Properties of Annealed SAE 4130 by Multilayer GTAW

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Journal of Iron and Steel Research International 2012年第7期19卷 71-78页

作者： I k lee C L Chung y T lee y T Chien Department of Materials Science and Engineering Da-Yeh University

During the first welding process in manufacturing a precise seam container, the steel material must first undergo a full annealing treatment. Multilayer welding operations are conducted and then applied with refining treatment to obtain the goal by hardening. The influence of thermal refining on mechanical properties of annealed SAE 4130 by multilayer GTAW （gas tungsten arc welding） was discussed. The AW （annealing＋welding） and AWST （annealing＋welding＋solution＋tempering） occurred with a minimum hardness value at GGHAZ （grain growth heat affected zone） due to coarse grain growth~ the hardness occurred with sudden drops between the multilayer welding, but was still larger than the minimum value at HAZ （heat affected zone）. The welded joint efficiency of the AWST was 89.9%, with the elongation reduced to 77.2% of AST （annealing＋solution＋tempering）. The cross section of the tensile samples both appeared with a uniform dimple-shaped structure, and however the necking for AST was greater than that for AWST. The impact value for AWST was 166.5% of AST. Moreover, from microstructure observations, it was found that AWST had a greater tendency to ductile failure than AST. These results can be inferred., the process of steady pressure and the initial position of the precision tube breakage HAZ. However, when stress occurs instantly, HAZ can absorb more energy, therefore the initial damage does not occur.

关键词： thermal refining SAE 4130 multilayer welding GTAW

Cortical hem signaling center: functions, development, and potential implications for evolution and brain disorders

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Neural Regeneration Research 2025年第4期20卷 1079-1080页

作者： Victor V.Chizhikov Igor y.Iskusnykh Department of Anatomy and Neurobiology University of Tennessee Health Science CenterMemphisTNUSA

Development of the telencephalon relies upon several signaling centers-localized cellular populations that supply secreted factors to pattern the cortical *** such signaling center is the cortical hem,which arises during embryonic development at the telencephalic dorsal midline,adjacent to the choroid plexus and hippocampal primordium(Figure 1A).While the cortical hem has also been described in reptiles and birds,most of our knowledge about the developmental roles of the cortical hem is derived from the analysis in *** cortical hem produces several types of secreted molecules,including wingless-related integration site(Wnt)and bone morphogenetic(Bmp)*** cortical hem is particularly important for the development of the hippocampus,which is involved in learning and memory,and the neocortex,which is the most complex brain region that mediates multiple types of behavior and higher cognitive functions(Mangale et al.,2008;Dal-Valle-Anton and Borrell,2022).

关键词： epithelium Figure center

Optimization of Mass Bleed Control for Base Drag Reduction of Supersonic Flight Bodies

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Journal of Thermal Science 2006年第3期15卷 206-212页

作者： y.-k.lee H.-D.kim School of Mechanical Engineering Andong National University388 Songcheon-dongAndong760-749Korea

The minimization of base drag using mass bleed control is examined in consideration of various base to orifice exit area ratios for a body of revolution in the Mach 2.47 freestream Axisymmetric, compressible, rmss-averaged Navier-Stokes equations are solved using the standard k-ω model, a fully implicit finite volume scheme, and a second order upwind scheme. Base flow charcteristics are explained mgaarding the base configuration as well as the injection parameter which is defined as the mass flow rate of bleed jet non-dimensionalized by the product of the base area and fieestream mass flux. The results obtained through the present study show that for a smaller base area, the optimum mass bleed condition leading to minimum base drag occurs at relatively larger mass bleed, and a lalger orifice exit can offer better drag control.

关键词： base drag mass bleed drag reduction separation supersonic flow

Plastic deformation behavior of Mg97Zn1y2 extruded alloys

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Transactions of Nonferrous Metals Society of China 2010年第7期20卷 1259-1268页

作者： k.HAGIHARA A.kINOSHITA y.SUGINO M.yAMASAkI y.kAWAMURA H.y.yASUDA y.UMAkOSHI Division of Materials and Manufacturing Science Graduate School of EngineeringOsaka University2-1Yamada-okaSuitaOsaka 565-0871Japan Department of Materials Science Kumamoto University2-39-1KurokamiKumamoto 860-8555Japan National Institute for Materials Science 1-2-1SengenTsukubaIbaraki 305-0047Japan

The mechanical properties of the Mg97Znly2 extruded alloy containing the long-period stacking ordered phase, the so-called LPSO-phase, with a volume fraction of 24%-25%, were examined by compression tests and cyclic tension-compression deformation tests. The plastic behavior of the extruded alloys with compositions of Mg99.2Zn0.2y0.6 and Mg89Zn4y7 （molar fraction, %）, which were almost the same compositions of Mg matrix phase and LPSO phase in Mg97Zn1y2 Mg/LPSO two-phase alloy, respectively, were also prepared. By comparing their mechanical properties, the strengthening mechanisms operating in the Mg97Zn1 y2 extruded alloy were discussed. Existence of the LPSO-phase strongly enhanced the refinement of Mg matrix grain size during extrusion, which led to a large increment of the strength of alloy. In addition, the LPSO-phases, which were aligned along the extrusion direction in Mg97Zn1y2 extruded alloy, acted as hardening phases, just like reinforced fibers.

关键词： plastic deformation yield stress LPSO-phase dislocation twinning