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Effective implementation and improvement of fast labeled multi-Bernoulli filter

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Journal of Systems Engineering and Electronics 2023年第3期34卷 661-673页

作者： CHENG Xuan JI Hongbing zhang Yongquan School of Electronic Engineering Xidian UniversityXi’an 710071China

Effective implementation of the fast labeled multi-Bernoulli(FLMB)filter is addressed for target tracking with interval ***,a sequential Monte Carlo(SMC)implementation of the FLMB filter,SMC-FLMB filter,is derived based on generalized likelihood function ***,a box particle(BP)implementation of the FLMB filter,BP-FLMB filter,is developed,with a computational complexity reduction of the SMC-FLMB ***,an improved version of the BP-FLMB filter,improved BP-FLMB(IBP-FLMB)filter,is proposed,improving its estimation accuracy and real-time performance under the conditions of low detection probability and high *** results show that the BP-FLMB filter has a great improvement of the real-time performance than the SMC-FLMB filter,with similar tracking *** with the BP-FLMB filter,the IBP-FLMB filter has better estimation performance and real-time performance under the conditions of low detection probability and high clutter.

关键词： multi-target tracking interval measurements fast labeled multi-Bernoulli(FLMB)filter sequential Monte Carlo(SMC)implementation box particle(BP)implementation

磁共振ESWAN序列对建立脑微出血病变等级制度的定量研究

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分子影像学杂志 2024年第3期47卷 242-248页

作者：宋诗倩吕月琴张琼方阮雯乐张银萍曾维陈伟张慧长沙医学院医学影像学院湖南长沙410219 中南大学湘雅医院放射科湖南长沙410028 长沙医学院人体解剖学教研室湖南长沙410219

目的应用磁共振三维增强多梯度回波t2^(*)加权血管成像(ESWAN)序列的相位值(PV)完善脑微出血(CMBs)影像诊断的分级标准。方法回顾性分析2021年5月~2022年5月在中南大学湘雅医院行ESWAN序列扫描的100例患有CMBs的脑小血管病(CSVD)患者、2... 详细信息

目的应用磁共振三维增强多梯度回波t2^(*)加权血管成像(ESWAN)序列的相位值(PV)完善脑微出血(CMBs)影像诊断的分级标准。方法回顾性分析2021年5月~2022年5月在中南大学湘雅医院行ESWAN序列扫描的100例患有CMBs的脑小血管病(CSVD)患者、29例脑内无异常影像表现且无其他基础疾病的健康志愿者。根据病变诊断结果将CSVD组分为CMBs组、腔隙性脑梗死(LI)组(CMBs单独合并LI)、脑白质病损(WML)组(CMBs单独合并WML)、LI+WML组。将局限于两个脑区内且LI的病灶数小于3个的定义为散发LI,否则为多发LI;FazekasⅠ级定义为轻度WML,否则为重度WML。采用医院后处理软件勾画并测量CSVD组各CMBs病灶以及健康组红核与黑质的PV值,分析CMBs病灶PV值与健康红核黑质的差异以及LI、WML病变发生状况与CMBs PV值的关系。结果CSVD组各脑区CMBs病灶与健康组红核、黑质的平均PV值差异均有统计学意义(F=65.599,P-0.74,CMBsⅡ级定义为PV值-0.81~-0.74,CMBsⅢ级定义为PV值-0.84~-0.81,CMBsⅣ级定义为PV值-0.89~-0.84,CMBsⅤ级定义为PV值<-0.89。结论CMBs病变与LI、WML病变程度相互影响;磁共振ESWAN序列的PV值能量化反映CMBs的病变程度,以此为依据建立CMBs的病变等级制度,有望取代目前相对主观的人工计数评估方式,辅助实现CMBs早期病灶的精准检出、CSVD疾病初期的快速诊断。

关键词：脑微出血三维增强多梯度回波t2^(*)加权血管成像磁共振定量诊断

气冷搅拌棒流变压铸在高强高导铝合金中的应用

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特种铸造及有色合金 2024年第3期44卷 289-293页

作者：祁明凡朱国明康永林王继成张莹李谷南张光金北京科技大学材料科学与工程学院北京100083 珠海市润星泰电器有限公司珠海519099 山东德泰机械制造集团有限公司青岛266599

开发了一种高效、低成本的铝合金均匀凝固控制制备大体积半固态浆料工艺——气冷搅拌棒工艺(Air-cooled stirring rod process,ACSR),将该制浆工艺与压铸机衔接形成多条一体化智能流变压铸生产线进行铝合金大型薄壁件流变压铸高效制备... 详细信息

开发了一种高效、低成本的铝合金均匀凝固控制制备大体积半固态浆料工艺——气冷搅拌棒工艺(Air-cooled stirring rod process,ACSR),将该制浆工艺与压铸机衔接形成多条一体化智能流变压铸生产线进行铝合金大型薄壁件流变压铸高效制备。目前,ACSR工艺可实现在30 s内制备出40 kg固相率为25%~35%的大体积半固态浆料。该流变压铸工艺已在新能源汽车、5G通信等高品质铝合金大型薄壁件的制备领域得到产业化应用,制备的典型产品包括5G通信用散热壳体、滤波器壳体、天线机箱与新能源汽车用三电结构壳体、端盖、ABS系统阀体等。与传统压铸件相比,新工艺制备的铝合金铸件显微组织细小圆整、表面品质好、内部气孔少,且具有更为优异的力学性能和导热系数。

关键词：铝合金均匀凝固控制半固态浆料流变压铸

Formation of intermetallic phases in unrefined and refined AA6082 Al alloys investigated by using SEM-based ultramicrotomy tomography

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Journal of Materials Science & technology 2022年第25期120卷 118-128页

作者： J.M.Yu t.Hashimoto H.t.Li N.Wanderka Z.zhang C.Cai X.L.Zhong J.Qin Q.P.Dong H.Nagaumi X.N.Wang Shagang School of Iron and Steel and High-Performance Metal Structural Materials Research Institute Soochow UniversitySuzhou 215137China School of Materials The University of ManchesterSackville StreetManchester M139PLUK Chinalco Materials Application Research Institute Co.Ltd. Beijing 102200China Helmholtz-Zentrum Berlin Für Materialien und Energie Hahn-Meitner-Platz 1Berlin 14109Germany Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China

the spatial arrangement,distribution and morphology of Fe-bearing intermetallics in AA6082 alloys depends on the manufacturing process of the alloy and thus influences the macroscopic ***,the microstructure of a near industrial scale casting AA6082 Al alloy fabricated by:(a)direct chill casting,(b)Al-5 ti-1 B grain refiner addition and(c)intensive melt shearing has been investigated by threedimensional visualization using SEM-based serial ultra microtomy *** formation sequence of phases in AA6082 alloys is generally categorized into four stages:formation ofα-Al grains,Fe-bearing intermetallics,Mg_(2)Si phase,and eutectic *** of three-dimensional visualization of the microstructure indicated that tiBparticles not only could nucleate Fe-bearingβ-intermetallics,but also could provide substrate for the formation of Fe-bearingα-intermetallics and Mg_(2)Si.A further deep analysis reveals that the essential condition for the formation of secondary phases such as Fe-bearing intermetallics and Mg_(2)Si phase is the build-up of a supersaturated solute front at theα-Al solid-liquid interface irrespective of the specific nucleation *** addition,the results indicate that grain refinement processing causes the severe interconnectivity of Fe-bearingα-***,the intensive melt shearing is a better manufacturing process because the intermetallics are more evenly distributed and refined than with the addition of the grain refiner,thereby improving the properties of the alloy.

关键词： Al-Si-Mg alloy Grain refinement Al-Fe-Si intermetallic phase tomography Ultramicrotomy Mg2Si

Ct双能量成像参数对肺结节病变性质的鉴别价值研究

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中国临床医学影像杂志 2024年第6期35卷 406-410页

作者：张东升盛茂何家伟陶磊合肥市第二人民医院影像中心安徽合肥230000

目的:研究Ct双能量成像参数对肺结节病变性质的鉴别价值。方法:2021年12月一2023年1月合肥市第二人民医院收治的102例恶性肺结节患者作为恶性组,同期收治的106例良性肺结节患者作为良性组,所有患者均经病理学检查确诊,比较两组患者影像... 详细信息

目的:研究Ct双能量成像参数对肺结节病变性质的鉴别价值。方法:2021年12月一2023年1月合肥市第二人民医院收治的102例恶性肺结节患者作为恶性组,同期收治的106例良性肺结节患者作为良性组,所有患者均经病理学检查确诊,比较两组患者影像学特征及Ct双能量成像参数,进行肺结节病变性质的Ct双能量成像征象、参数多因素分析,采用受试者工作特征(ROC)曲线分析Ct双能量成像参数对肺结节病变性质的鉴别价值。结果:恶性组强化不均匀、淋巴结增大、结节边缘毛刺/分叶、血管受累患者占比高于良性组(Pt剂量指数均高于良性组(Ptic回归分析结果显示,动脉期、静脉期能谱曲线斜率及容积Ct剂量指数较高是肺结节恶性病变的危险因素(OR=1.451、1.502、1.640,Pt剂量指数联合鉴别肺结节病变性质的曲线下面积(AUC)值高于三者单独检测(Pt剂量指数存在明显差异,且动脉期、静脉期能谱曲线斜率及容积Ct剂量指数是肺结节恶性病变的危险因素,三者联合对肺结节病变性质的鉴别具有较好价值。

关键词：肺肿瘤体层摄影术,螺旋计算机

Finite-time H_(∞)Sampled-Data Reliable Control for a Class of Markovian Jump Systems with Randomly Occurring Uncertainty via t-S Fuzzy Model

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Journal of Systems Science & Complexity 2022年第3期35卷 860-887页

作者： LIU Yuanyuan zhang Yutong MA Yuechao School of Science Yanshan UniversityQinhuangdao 066004China

the paper analyzes finite-time H_(∞)sampled-data reliability control for nonlinear continuous time Markovian jump systems with randomly occurring uncertainty on account of t-S fuzzy *** particular,the transition rates of the Markovian jump systems have both the upper bound and lower ***,a new Lyapunov-Krasovskii functional(LKF)is considered,which fully captures the available characteristics of real sampling period,and a sampled-data controller with nonlinear actuator failures is *** on the integral inequality technique,some less conservative conditions are proposed such that the stochastic fuzzy system is reliable in the sense,which satisfies finite-time bounded and certain H_(∞)performance levelγ.Additionally,some numerical examples can illustrate the effectiveness of the results.

关键词： Actuator fault control finite-time H_(∞)bounded Markovian jump system sampled-data control t-S fuzzy model

Quantum algorithms of state estimators in classical control systems

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Science China(Information Sciences) 2020年第9期63卷 243-254页

作者： Kai LI Hongyi DAI Ming zhang College of Intelligence Science National University of Defense Technology College of Liberal Arts and Sciences National University of Defense Technology

In this paper, quantum algorithms are applied to the design of state estimators in classical control systems under the condition that quantum algorithms can be physically implemented. We demonstrate that the design of state estimators can be solved by quantum algorithms, which may achieve significant acceleration in comparison to traditional classical algorithms. the time complexity can be reduced from O(n6) to O(qn)when the system matrix is sparse and the condition number κ and the reciprocal of precision ? are small in size O(poly log(n)), where n is the dimension of state x(t) and q is the dimension of input u(t). Our research will provide an entire quantum scheme of constructing state estimators and can be regarded as an attempt to widen application scope of quantum computation.

关键词： quantum computation estimators for linear systems optimization algorithms quantum acceleration time complexity

Simultaneous Determination of Catecholamines and Related Metabolites by Capillary Electrophoresis with Amperometric Detection

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Chemical Research in Chinese Universities 2013年第5期29卷 850-853页

作者： zhang Hai-tao LI Zhuo zhang Jun-bo zhang Yang YE Jian-nong CHU Qing-cui zhang Mei-jiang Department of Chemistry East China Normal University Shanghai 200241 P. R. China Key Laboratory of Adolescent Health Assessment and Exercise Intervention Ministry of Education School of Sports and Health Care East China Normal University Shanghai 200062 P R. China

An electrophoretic method was developed for the determination of several important catecholamine markers, namely norepinephrine, epinephrine, dopamine, metanephrine, vanillylmandelic acid and homovanillic acid in urine samples. Under the optimum conditions, the six marker compounds could be well separated with the major coexisting interference compound uric acid within 24 rain at a separation voltage of 16 kV in a borate running buffer （80 mmol/L, pH=9.48）. Highly linear response can be obtained over three orders of magnitude for the above markers with the low limits of detection ranging from 1.0 ng/mL to 5.0 ng/mL（S/N=3）. the proposed capillary electrophoresis with amperometric detection（CE-AD） method has been used to simultaneously determine the six catecholamine markers in urine samples of healthy volunteers and patients suffering from different diseases avoiding redundant measurements and high assay cost; and the electrochemical profiles can suggest more diagnostic information of multiple diseases, which provides a promising and convenient entry into primary diagnoses of several clinical diseases.

关键词： Amperometric detection Capillary electrophoresis Catecholamine Metabolic marker Urine

Performance of switch between exchange bias and coercivity:Influences of antiferromagnetic anisotropy and exchange coupling

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Journal of Materials Science & technology 2022年第25期120卷 186-195页

作者： Ruijun Li Fan zhang Yong Hu Department of Physics College of SciencesNortheastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China Department of Logistics Management Liaoning Provincial College of CommunicationsShenyang 110122China

the study on temperature dependence of exchange bias field and coercivity is crucial to solving the writing/reading dilemma in magnetic *** by recent experimental findings,a complete switch between exchange bias field and coercivity with temperature is proposed,and the performance,characterized by average switching temperature(t_(S))and switching temperature width(t_(W)),controlled by antiferromagnetic anisotropy(KAF)and exchange coupling(J_(AF))constants is studied based on a MonteCarlo *** results show that a linear relationship between t_(S)and KAFis established when KAFis above a critical value,while t_(S)is weakly influenced by J_(AF).On the contrary,t_(W)is insensitive to KAF,while strongly depends on J_(AF).Besides overcoming thermal energy,the increase of KAFfor a small J_(AF)guarantees the completely frozen states in the antiferromagnetic layers during magnetizing at higher temperature,below which the exchange bias field exists with a negligible ***,for a large J_(AF),the uncompensated antiferromagnetic magnetization behavior during the ferromagnetic magnetization reversal becomes complicated,and the switching process in the low temperature range depends on the irreversibility of uncompensated antiferromagnetic magnetization reversal during magnetizing,while in the high temperature range mainly influenced by the field-cooling process,resulting in a large t_(W).this work provides an opportunity to control/optimize the performance of the temperatureinduced switch between unidirectional and uniaxial symmetries through precisely tuning KAFand/or J_(AF)to meet different application demands in the next generation information technology.

关键词： Magnetic recording Ferromagnet/antiferromagnet multilayer Exchange-bias/coercivity switch temperature dependence Antiferromagnetic anisotropy Antiferromagnetic exchange coupling Monte-Carlo simulation