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Automated Silicon-Substrate Ultra-Microtome for Automating the Collection of Brain Sections in Array Tomography

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IEEE/CAA Journal of Automatica Sinica 2021年第2期8卷 389-401页

作者： long Cheng Weizhou Liu Chao Zhou Yongxiang zou Zeng-guang Hou the State Key Laboratory of Management and Control for Complex Systems Institute of AutomationChinese Academy of SciencesBeijing 100190 the School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China

Understanding the structure and working principle of brain neural networks requires three-dimensional reconstruction of brain tissue samples using array tomography *** order to improve the reconstruction performance,the sequence of brain sections should be collected with silicon wafers for subsequent electron microscopic ***,the current collection of brain sections based on silicon substrate involve mainly manual collection,which requires the involvement of automation techniques to increase collection *** paper presents the design of an automatic collection device for brain ***,a novel mechanism based on circular silicon substrates is proposed for collection of brain sections;second,an automatic collection system based on microscopic object detection and feedback control strategy is *** results verify the function of the proposed collection *** objects(brain section,left baffle,right baffle)can be detected from microscopic images by the proposed detection *** efficiency can be further improved with position feedback of brain sections *** has been experimentally verified that the proposed device can well fulfill the task of automatic collection of brain *** the help of the proposed automatic collection device,human operators can be partially liberated from the tedious manual collection process and collection efficiency can be improved.

关键词： Array tomography automatic collection system brain sections microscopic object detection serial section

Magnetic field assisted Fenton reactions for the enhanced degradation of methyl blue

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Chinese Chemical Letters 2009年第1期20卷 99-101页

作者： Xiao long Hao Lu Yi zou guang Sheng Zhang Yi Bo Zhang Laboratory of Environmental Pollution Prevention School of Environmental and Civil Engineering Jiangnan University Wuxi 214122 China

Magnetic field was tentatively introduced into Fenton reactions system for the degradation and discoloration of methyl blue as the represent of organic chemical dye, which was a bio-refractory organic pollutant in industry wastewater. It was found that under optimal Fenton reaction conditions, with the assistant of magnetic field in Fenton reactions, the degradation rate of methyl blue, the decomposition rate of H2O2 and the conversion rate of Fe^2＋ were accelerated, the extent of them would be improved by the increase of magnetic field intensity. Meanwhile, the mineralization of methyl blue （CODer） was improved by over 10% with magnetic field.

关键词： Magnetic field Fenton reactions Methyl blue Dye

On the efficient search of punctured convolutional codes with simulated annealing algorithm

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The Journal of China Universities of Posts and Telecommunications 2014年第2期21卷 69-74,82页

作者： zou Wei-xia WANG Zhen-yu WANG Gui-ye DU guang-long GAO Ying Key Laboratory of Wireless Universal Communications Beijing University of Posts and Telecommunications School of Electronic Engineering Beijing University of Posts and Telecommunications

Punctured convolution codes （PCCs） have a lot of applications in modem communication system. The efficient way to search for best PCCs with longer constraint lengths is desired since the complexity of exhaustive search becomes unacceptable. An efficient search method to find PCCs is proposed and simulated. At first, PCCs＇ searching problem is turned into an optimization problem through analysis of PCCs＇ judging criteria, and the inefficiency to use pattern search （PS） for many local optimums is pointed out. The simulated annealing （SA） is adapted to the non-convex optimization problem to find best PCCs with low complexity. Simulation indicates that SA performs very well both in complexity and success ratio, and PCCs with memories varying from 9 to 12 and rates varying from 2/3 to 4/5 searched by SA are presented.

关键词： PCCs optimization problem pattern search simulated annealing

Influences of ^7Li enrichment on Th-U fuel breeding for an Improved Molten Salt Fast Reactor(IMSFR)

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Nuclear Science and Techniques 2017年第7期28卷 105-113页

作者： guang-Chao Li Yang zou Cheng-Gang Yu Jian-long Han Jin-Gen Chen Hong-Jie Xu Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China CAS Innovative Academies in TMSR Energy System Shanghai 201800 China University of Chinese Academy of Sciences Beijing 100049China

The molten salt fast reactor(MSFR) shows great promise with high breeding ratio(BR),large negative temperature coefficient of reactivity,high thermal-electric conversion efficiency,inherent safety,and online *** on an improved MSFR optimized by adding axial fertile salt and a graphite reflector,the influences of ~7Li enrichment on Th-U breeding are investigated,aiming to provide a feasible selection for the molten salt with high fissile breeding and a relatively low technology requirement for ~7Li *** the self-developed molten salt reactor reprocessing sequence based on SCALE6.1,the burn-up calculations with online reprocessing are carried *** are explored including BR,^(233)U production,double time(DT),spectrum,~6Li inventory,neutron absorption,and the tritium *** results show that the Li enrichment of 99.95% is appropriate in the fast fission *** this case,BR above 1.10 can be achieved for a long time,corresponding to the ^(233)U production of130 kg per year and DT of 36 *** 80 years' operation,the tritium production for 99.5% is only about 7kg,and there is no obvious increase compared to that for 99.9995%.

关键词：繁殖率熔盐富集铀燃料裂变反应堆快堆在线处理负温度系数

Cancellation of nonlinear distortion based on integration of FCM clustering algorithm and adaptive-two-stage linear approximation

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The Journal of China Universities of Posts and Telecommunications 2014年第3期21卷 18-22页

作者： WANG Gui-ye zou Wei-xia WANG Zhen-yu DU guang-long GAO Ying Key laboratory of wireless universal communications Beijing University of Posts and Telecommunications School of Electronic Engineering Beijing University of Posts and Telecommunications

A hybrid system of the fuzzy c-means （FCM） clustering algorithm and adaptive-two-stage linear approximation was presented for nonlinear distortion cancellation of radio frequency （RF） power amplifier （PA）. This mechanism can effectively eliminate noise, adaptively model PA＇s instantaneous change, and efficiently correct nonlinear distortion. This article puts forward the FCM clustering algorithm for clustering received signals to eliminate white noise, and then uses the adaptive-two-stage linear approximation to fit the inverse function of the amplitude＇s and phase＇s nonlinear mapping during the training phase. Parameters of the linear function and similarity function are trained using the gradient-descent and minimum mean-square error criteria. The proposed approach＇s training results is directly employed to eliminate sampling signal＇s nonlinear distortion. This hybrid method is realized easier than the multi-segment linear approximation and could reduce the received signal＇s bit error rate （BER） more efficiently.

关键词： PA nonlinear distortion cancellation FCM clustering algorithm similarity function adaptive-two-stage linear approximation

CONVERGENCE OF INNER ITERATIONS SCHEME OF THEDISCRETE ORDINATE METHOD IN SPHERICAL GEOMETRY

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Journal of Computational Mathematics 2005年第3期23卷 321-326页

作者： Zhi-junShen guang-weiYuan long-junShen LaboratoryofComputationalPhysics InstituteofAppliedPhysicsandComputationalMathematicsP.O.Box8009Beijing100088China

In transport theory, the convergence of the inner iteration scheme to the spherical neutron transport equation has been an open problem. In this paper, the inner iteration for a positive step function scheme is consid... 详细信息

关键词： transport equation discrete ordinate inner iteration

Investigation on the temperature distribution and strength of flat steel ribbon wound cryogenic high-pressure vessel

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第2期8卷 210-215页

作者： CUI Xiao-long CHEN guang-ming Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

By analyzing heat transfer on the wall of fiat steel ribbon wound vessel （FSRWV）, a numerical model of temperature distribution on the entire wall （including inner core wall, flat steel ribbons, outside cylinder of jacket and insulating layer） was established by the authors. With the model, the temperature distribution and the length change in the vessel walls and flat steel ribbons in low temperature are calculated and analyzed. The results show that the flat steel ribbon wound cryogenic high-pressure vessel is simpler in structure, safer and easier to manufacture than those of conventional ones.

关键词： Cryogenic high-pressure vessel Flat steel ribbon wound vessel (FSRWV) Temperature distribution Numerical simulation

Crystallization behavior of blast furnace slag modified by adding iron ore tailing

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Journal of Iron and Steel Research International 2017年第6期24卷 601-607页

作者： Qian-qian Ren Yu-zhu Zhang Yue long Shao-sheng Chen Zong-shu zou Jie Li Chen-guang Xu School of Metallurgy Northeastern University Shenyang 110819 Liaoning China State Key Laboratory of Advanced Steel Processes and Products Central Iron and Steel Research Institute Beijing 100081 China College of Metallurgy and Energy North China University of Science and Technology Tangshan 063009 Hebei China

Blast furnace （BF） slag is a by-product of the ironmaking process and could be utilized to manufacture slag fiber by adding iron ore tailing. The crystallization behavior of the modified BF slag is significant to the fi- brosis process. To investigate the influence of basieity on the crystallization behavior, BF slag was modi- fied by adding iron ore tailing at room temperature and melted at 1 500 ℃. FactSage simulation, X-ray dif- fraction, scanning electron microscopy backscattered electron imaging coupled to an energy dispersive spectrometer, and hot thermocouple technique analysis were performed to explore the crystallization be- havior of the modified BF slag during the cooling process. It was found that the initial crystallization tem- perature increased with the increase in basicity. Melilite, anorthite, clinopyroxene, and wollastonite could be generated during the cooling process as basicity ranged from 0.7 to 0.9. Spinel could be found as one of the phases; however, wollastonite disappeared under a basicity of 1.0. The initial crystallization tempera- ture was controlled by the crystallization of melilite during the cooling process when the basicity of the modified BF slag ranged from 0. 7 to 1.0. Moreover, the cooling rate could also influence the crystalliza- tion of the modified BF slag.

关键词： Crystallization behaviorModified blast furnaceslagBasicityInitial crystallizationtemperatureIron ore tailing

Covariate-Assisted Matrix Completion with Multiple Structural Breaks

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Journal of Systems Science & Complexity 2024年第2期37卷 692-728页

作者： MENG Jing FENG long zou Changliang WANG Zhaojun School of Statistics and Data Science KLMDASRLEBPSand LPMCNankai UniversityTianjin 300071China

In matrix completion,additional covariates often provide valuable information for completing the unobserved entries of a high-dimensional low-rank matrix *** this paper,the authors consider the matrix recovery problem when there are multiple structural breaks in the coefficient matrix β under the column-space-decomposition model A=Xβ+B.A cumulative sum(CUSUM)statistic is constructed based on the penalized estimation of β.Then the CUSUM is incorporated into the Wild Binary Segmentation(WBS)algorithm to consistently estimate the location of ***,a nearly-optimal recovery of A is *** findings are further corroborated via numerical experiments and a real-data application.

关键词： Additional covariates matrix completion multiple structural breaks wild Binary Segmentation