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基于MRI的影像组学模型预测保乳术后乳腺癌病人手术切缘状态并推断肿瘤免疫微环境：一项多中心验证研究

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国际医学放射学杂志 2024年第3期 374-375页

作者： j.ma K.Chen S.Li L.Zhu Y.Yu j.Li 梁媛

摘要目的术前准确评估保乳手术切缘阳性的风险，有助于制定手术计划。该项多中心验证研究开发了一种基于MRI的影像组学模型来预测手术切缘状态。方法回顾性

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EXPERIMENTAL RESEARCH OF CYLINDER TO BED HEAT TRANSFER IN AGITATED FLUIDIZED BEDS

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journal of Hydrodynamics 2000年第4期12卷 36-40页

作者： ma, j.H. Dep. of Air-condition Eng. Shandong Inst. of Archit. and Eng. Jinan 250014 China

Cylinder-to-bed heat transfer in agitated fluidized beds was studied experimentally. In the experiments, the aluminum particles were used as bed material, the diameter of those ranged from 0.5 mm to 2 mm. The effects of gas velocity, particles size, and agitator rotary speed on heat transfer were studied. From the experimental results, we have come to the following conclusion: (1) there are optimal ranges for airflow velocity and rotary speed to get optimal heat transfer coefficient; (2) the cylinder-to-bed heat transfer is greatly affected by gas velocity, rotary speed and particles sizes, and the effect of rotary speed on heat transfer is similar to that of gas velocity; (3) higher heat transfer coefficient is obtained with smaller particles.

关键词： Fluidized beds Heat transfer mass transfer Two phase flow

A hybrid multi-degree-of-freedom vibration isolation platform for spacecrafts by the linear active disturbance rejection control

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Applied mathematics and Mechanics(English Edition) 2020年第5期41卷 805-818页

作者： Weichao CHI S.j.ma j.Q.SUN College of Science Northeastern UniversityShenyang 100819China Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang 100819China Department of Mechanical Engineering School of EngineeringUniversity of CaliforniaMercedCA 95343U.S.A.

The hybrid vibration isolation, which takes advantages of both the passive and active approaches, has been an important solution for space missions. The objective of this paper is to design a vibration isolation platform for payloads on spacecrafts with the robust, wide bandwidth, and multi-degree-of-freedom(MDOF). The proposed solution is based on a parallel mechanism with six voice-coil motors(VCMs) as the actuators. The linear active disturbance resistance control(LADRC) algorithm is used for the active control. Numerical simulation results show that the vibration isolation platform performs effectively over a wide bandwidth, and the resonance introduced by the passive isolation is eliminated. The system robustness to the uncertainties of the structure is also verified by simulation.

关键词： hybrid vibration isolation Stewart platform linear active disturbance rejection control(LADRC) stability robustness

Cloning and functional characterization of two cDNAs encoding NADPH-dependent 3-ketoacyl-CoA reductased from developing cotton fibers

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Cell Research 2005年第6期15卷 465-473页

作者： Francois ma PUjOL,Alexander j KASTANIOTIS,j Kalervo HILTUNEN Biocenter Oulu and Department of Biochemistry University of Oulu P.O. Box 3000 FIN-90014 University of Oulu Finland Biocenter Oulu and Department of Biochemistry University of Oulu P.O. Box 3000 FIN-90014 University of Oulu Finland Biocenter Oulu and Department of Biochemistry University of Oulu P.O. Box 3000 FIN-90014 University of Oulu Finland

Genes encoding enzymes involved in biosynthesis of very long chain fatty acids were significantly up-regulatedduring early cotton fiber development. Two cDNAs, GhKCR1 and GhKCR2 encoding putative cotton 3-ketoacyl-CoAreductases that catalyze the second step in fatty acid elongation, were isolated from developing cotton fibers. GhKCR1and 2 contain open reading frames of 963 bp and 924 bp encoding proteins of 320 and 307 amino acid residues,respectively. Quantatitive RT-PCR analysis showed that both these genes were highly preferentially expressed duringthe cotton fiber elongation period with much lower levels recovered from roots, stems and leaves. GhKCR1 and 2showed 30%-32% identity to Saccharomyces cerevisiae Ybr159p at the deduced amino acid level. These cotton cDNAswere cloned and expressed in yeast haploid ybr159w? mutant that was deficient in 3-ketoacyl-CoA reductase ***-type growth rate was restored in ybr159w? cells that expressed either GhKCR1 or 2. Further analysis showed thatGhKCR1 and 2 were co-sedimented within the membranous pellet fraction after high-speed centrifugation, similar to theyeast endoplasmic reticulum marker ScKar2p. Both GhKCR(s) showed NADPH-dependent 3-ketoacyl-CoA reductaseactivity in an in vitro assay system using palmitoyl-CoA and malonyl-CoA as substrates. Our results suggest thatGhKCR1 and 2 are functional orthologues of ScYbr159p.

关键词： very-long-chain fatty acids endoplasmic reticulum fatty acid elongation system 3-ketoacyl-CoA reductase Gossypium hirsutum short-chain alcohol dehydrogenase/reductase protein family.

Synthesis of silica-pillared layered lanthanum titanate with high thermal stability

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Chinese journal of Chemistry 1996年第2期14卷 186-189页

作者： Wang, NP Hou, WH ma, j Yan, Qj NANjING UNIV INST COORDINAT CHEMDEPT CHEMNANJING 210093JIANGSUPEOPLES R CHINA

It is now well established that layered solids other than smectite clays may bepillared to form three-dimensional crosslinked materials, the porosity of which isultimately tunable by the nature of the host substrate a... 详细信息

关键词： pillaring aminopropyltriethoxysilane potassium lanthanum titanate

The joint Control of Variable Speed and On-Ramp Metering for Urban Expressway

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journal of Systems Engineering and Electronics 2001年第3期12卷 25-30页

作者： ma, j. Liu, X. Rong, j. Li, Z. Transportation Research Center Beijing Polytechnic University Beijing 100022 China

The traffic performance of urban expressway is subject to non-recurring and recurring events, which may cause heavy congestion and vehicles long queuing on ramps. The low performance may bring more traffic delay to the whole network of urban road. This paper presents a new method, the joint control of variable speed control and on-ramp metering, which attempts to improve the level of traffic operations on urban expressway. By analyzing traffic flow on urban expressway, an optimum control strategy of variable speed and on-ramp metering is established in the paper.

关键词： Function evaluation Highway traffic control Intelligent control mathematical models Motor transportation Parameter estimation Ramp generators Speed control

Numerical study of the circular opening effect on mechanical behaviour of rock under confinement

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journal of Rock Mechanics and Geotechnical Engineering 2019年第6期11卷 1201-1210页

作者： Y.L.Gui j.L.Shang j.j.ma Z.Y.Zhao school of engineering newcastle universitynewcastle upon tynene17ruunited kingdom school of civil and environmental engineering nanyang technological university639798singapore school of civil engineering sun yat-sen universityguangzhou510275china

Opening holes in rock including their size and distribution can affect the performance of rock-related structures.A good understanding on this will contribute to,for example,rock cavern design,and construction,tunnelling,and mining *** improve the understanding,a comprehensive investigation of the opening hole effect on the rock mechanical behaviour under biaxial loading condition is carried out by virtue of a hybrid continuum-discrete element *** specimens with both single hole and multi-hole of various radii are investigated and compared with the cases subjected to uniaxial *** is demonstrated that the confining pressure can increase both the stiffness and strength due to delaying the crack initiation and *** increase due to the confining pressure is more evident for the compressive *** single hole specimens with 0.75 mm radius hole,the increase ratio of the compressive strength is a linear increasing function with width and the increase ratio ranges from 2.15 for the specimen with 3.5 mm width to 2.45 for 10 mm *** the single hole specimen with 10 mm width,the increase ratio starts at 2.13 for the specimen with 0.75 mm radius hole,ascending to the peak of 2.37 for the specimen with 1 mm radius hole,followed by a decline to 2.2 for the specimen with 1.25 mm radius ***,for the multi-hole specimens,the increase ratio varies from 1.66 to *** addition,to verify the influence of confining pressure magnitude on the performance of the rock specimens,totalling 10 confining pressure levels are applied and *** simulation results show that even though there are opening holes in the specimens,the simulated compressive strength generally follows the generalised Hoek-Brown model.

关键词： Rock with opening Simulation Biaxial loading Strength Stiffness

Evolution of microstructure and phase composition of Ti-3Al-5Mo-4.5V alloy with varied β phase stability

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journal of materials Science & Technology 2018年第12期34卷 2325-2330页

作者： Q.Xue Y.j.ma j.F.Lei R.Yang C.Wang School of Metallurgy Northeastern University Institute of Metal Research Chinese Academy of Sciences

The microstructure evolution and phase composition of an α+β titanium alloy, Ti-3Al-5Mo-4.5V(wt.%),have been investigated. Electron probe micro analysis(EPma) quantitative results manifest that the stability of β phase decreases with increasing quenching temperature, which is influenced by the significant variation of β-stabilizing elements concentration. Detailed microstructure analysis shows that the β→ωphase transformation does occur when quenching at 750℃ and 800 ℃. The ω-reflections change from incommensurate ω-spots(750 ℃) to ideal ω-spots(800 ℃) as the β stability of the alloy decreases. Further the decrease of β phase stability encourages the formation of athermal α " martensite, which has the following orientation relationships: [111]β//[110]α",[100]p//[100]α " and [-110]p//[00-1]α" with respect to the β matrix.

关键词： Dual-phase titanium alloy β phase stability ω phase α" martensite Microstructure

Influence of wall slip on the hydrodynamic behavior of a two-dimensional slider bearing

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Acta Mechanica Sinica 2007年第6期23卷 655-661页

作者： G. j. ma C. W. Wu P. Zhou State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering Mechanics Dalian University of Technology Dalian 116024 China

In the present paper, a multi-linearity method is used to address the nonlinear slip control equation for the hydrodynamic analysis of a two-dimensional （2-D） slip gap flow. Numerical analysis of a finite length slider bearing with wall slip shows that the surface limiting shear stress exerts complicated influences on the hydrodynamic behavior of the gap flow. If the slip occurs at either the stationary surface or the moving surface （especially at the stationary surface）, there is a transition point in the initial limiting shear stress for the proportional coefficient to affect the hydrodynamic load support in two opposite ways： it increases the hydrodynamic load support at higher initial limiting shear stresses, but decreases the hydrodynamic load support at lower initial limiting shear stresses. If the slip occurs at the moving surface only, no fluid pressure is generated in the case of null initial limiting shear stress. If the slip occurs at both the surfaces with the same slip property, the hydrodynamic load support goes off after a critical sliding speed is reached. A small initial limiting shear stress and a small proportionality coefficient always give rise to a low friction drag.

关键词： Wall slip Slider beating Multi-linearity method Quadratic programming