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Inverse Markov Process Based Constrained Dynamic Graph Layout

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Journal of Computer Science & Technology 2021年第3期36卷 707-718页

作者： shi-Ying Sheng Sheng-Tao Chen Xiao-Ju Dong chun-Yuan Wu Xiao-Ru Yuan ParisTech elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China Department of Computer Science and engineering Shanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Machine Perception(Ministry of education) National Engineering Laboratory for Big Data Analysis and ApplicationPeking UniversityBeijing 100080China

In online dynamic graph drawing,constraints over nodes and node pairs help preserve a coherent mental map in a sequence of *** the constraints is challenging due to the requirements of both preserving mental map and satisfying the visual aesthetics of a graph *** existing algorithms basically depend on local changes but fail to do proper evaluations on the global propagation when setting *** solve this problem,we introduce a heuristic model derived from PageRank which simulates the node movement as an inverse Markov process hence to give a global analysis of the layout's change,according to which different constraints can be *** constraints,along with stress function,generate layouts maintaining spatial positions and shapes of relatively stable substructures between adjacent *** demonstrate that our method preserves both structure and position similarity to help users track graph changes visually.

关键词： graph drawing data stream dynamic graph layout

Combination of olfactory ensheathing cells and human umbilical cord mesenchymal stem cell-derived exosomes promotes sciatic nerve regeneration

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Neural Regeneration Research 2020年第10期15卷 1903-1911页

作者： Yang Zhang Wen-Tao Wang chun-Rong Gong Chao Li Mei shi Department of Radiation Oncology Xijing HospitalAir Force Medical UniversityXi’anShaanxi ProvinceChina Department of Orthopedics Changhai HospitalNaval Medical UniversityShanghaiChina Rehabilitation Center North District Hospital of the People’s Hospital of Lin Yi CityLinyiShandong ProvinceChina Department of Orthopedics The Eighth Medical Center of Chinese PLA general HospitalBeijingChina

Olfactory ensheathing cells(OeCs)are promising seed cells for nerve ***,their application is limited by the hypoxic environment usually present at the site of *** derived from human umbilical cord mesenchymal stem cells have the potential to regulate the pathological processes that occur in response to *** ability of OeCs to migrate is unknown,especially in hypoxic conditions,and the effect of OeCs combined with exosomes on peripheral nerve repair is not *** understanding of these issues will enable the potential of OeCs for the treatment of nerve injury to be *** this study,OeCs were acquired from the olfactory bulb of Sprague Dawley *** umbilical cord mesenchymal stem cell-derived exosomes(0–400μg/mL)were cultured with OeCs for 12–48 *** culture with 400μg/mL exosomes for 24 hours,the viability and proliferation of OeCs were significantly *** observed changes to OeCs subjected to hypoxia for 24 hours and treatment with *** significantly promoted the survival and migration of OeCs in hypoxic conditions,and effectively increased brain-derived neurotrophic factor gene expression,protein levels and ***,using a 12 mm left sciatic nerve defect rat model,we confirmed that OeCs and exosomes can synergistically promote motor and sensory function of the injured sciatic *** findings show that application of OeCs and exosomes can promote nerve regeneration and functional *** study was approved by the Institutional ethical Committee of the Air Force Medical University,China(approval ***-20181004)on October 7,2018;and collection and use of human umbilical cord specimens was approved by the ethics Committee of the Linyi People’s Hospital,China(approval No.30054)on May 20,2019.

关键词： brain-derived neurotrophic factor cell migration cell viability functional recovery hypoxia nerve regeneration sciatic functional index sciatic nerve injury

Multiscale observation of Li plating for lithium-ion batteries

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Rare Metals 2021年第11期40卷 3038-3048页

作者： Xin-Lei Gao Xin-Hua Liu Wen-Long Xie Li-Sheng Zhang shi-chun Yang School of Transportation Science and engineering Beihang UniversityBeijing 100191China

As the most hazardous side reaction,Li plating poses high risks of undermining electrochemical performance of Li-ion batteries by accelerating *** some extreme abuse conditions,Li plating can even jeopardize safety performance and induce catastrophic results like thermal ***,multiscale observation of Li plating is of great significance for understanding the internal mechanisms and early detection of Li *** this mini-review,the recent progress of formation mechanisms of plated metallic lithium was ***,the in situ and ex situ observation methods of macroscopic,microscopic and atomic level were *** electrode provides a promising tool for real-time monitoring of anode potential,which is the critical factor of Li plating,showing great potentials in cloudbased battery management ***,some perspectives for future researches on Li plating observation and corresponding utilizations in developing Li plating free control strategies were proposed.

关键词： Lithium-ion battery Li plating Multiscale observation Reference electrodes

Improved particle swarm optimization algorithm for multi-reservoir system operation

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Water Science and engineering 2011年第1期4卷 61-73页

作者： Jun ZHANG Zhen WU chun-tian CHeNG shi-qin ZHANG Zhejiang electric Power Dispatching and Communication Center Hangzhou 310007 R R. China Department of Civil and Hydraulic engineering Dalian University of Technology Dalian 116024 P. R. China Fujian electric Power Dispatching and Communication Center Fuzhou 350003 R R. China

In this paper, a hybrid improved particle swarm optimization （IPSO） algorithm is proposed for the optimization of hydroelectric power scheduling in multi-reservoir systems. The conventional particle swarm optimization （PSO） algorithm is improved in two ways：（1） The linearly decreasing inertia weight coefficient （LDIWC） is replaced by a self-adaptive exponential inertia weight coefficient （SeIWC）, which could make the PSO algorithm more balanceable and more effective in both global and local searches. （2） The crossover and mutation idea inspired by the genetic algorithm （GA） is imported into the particle updating method to enhance the diversity of populations. The potential ability of IPSO in nonlinear numerical function optimization was first tested with three classical benchmark functions. Then, a long-term multi-reservoir system operation model based on IPSO was designed and a case study was carried out in the Minjiang Basin in China, where there is a power system consisting of 26 hydroelectric power plants. The scheduling results of the IPSO algorithm were found to outperform PSO and to be comparable with the results of the dynamic programming successive approximation （DPSA） algorithm.

关键词： particle swarm optimization self-adaptive exponential inertia weight coefficient multi-reservoir system operation hydroelectric power generation Minjiang Basin

Investigation on a Sol-gel Coating Containing Inhibitors on 2024-T3 Aluminum Alloy

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Chinese Journal of Aeronautics 2006年第B12期19卷 106-112页

作者： shi Hong-wei LIU Fu-chun HAN en-hou SUN Ming-cheng environmental Corrosion Center Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

For a long time, chromate incorporated conversion coatings have been drawn special attention in corrosion protection of aircraft-used aluminum alloys. However, ever-increasing environmental pressures requires that non-chromate conversion coatings be developed because of the detrimental carcinogenic effects of the chromate compounds. In recent years, the sol-gel coatings doped with inhibitors were developed to replace chromate conversion coatings, and showed real promise; A sol-gel coating was prepared and its anti-corrosion behavior was investigated using the potentiodynamic scanning （PDS） and the electrochemical impedance spectroscopy （eIS）. It is found that the sol-gel coating obtained by the hydrolysis and condensation of 3-glycidoxypropyltrimethoxysilane （GPTMS） and tetramethoxysilane （TMOS） is prone to form defects if cured at the room temperature, whereas if cured at a higher temperature （100℃）, these flaws can be avoided. Furthermore, it can be seen that addition of anti-foam agents and surfactants will reduce the faults if cured at the room temperature. effects of the corrosion inhibitors, CeCl3 and mercaptobenzothiazole （MBT）, in the sol-gel coatings on 2024-T3 aluminum alloy were also investigated. Results show that the corrosion resistance of the sol-gel coatings containing CeCl3 proves to be better than that of the pure and MBT added sol-gel coatings by the electrochemical methods.

关键词： corrosion protection sol-gel coating electrochemical impedance spectroscopy (eIS) inhibitor potentiodynamic scan (PDS) aluminum alloy

Deformation Behavior of Mg-8 wt%Li Alloy under High-speed Impact

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Chinese Journal of Aeronautics 2006年第B12期19卷 235-238页

作者： SHA Gui-ying LIU chun-zhong YU Tao shi Ji-hong Department of Materials engineering Shenyang Institute of Aeronautical Engineering Shenyang 110034 China

Deformation behavior of the Mg-8 wt%Li alloy at high strain rate was studied by means of the Split Hopkinson Pressure Bar （with strain rate of 10^3 s^-1）. It is found that shear localization proves to be the main damage mode for the alloy during dynamic loading. Strain and strain rate arc the two necessary parameters affecting the occurrence of deformation and shear bands. Deformation bands begin to form when the strain and strain rate reach 0.20 and 1 900 s^-1 respectively and will develop gradually with the strain rate increasing. Besides, deformation bands will transform into shear bands when the strain and strain rate reach above 0.25 and 3 500 s^-1 separately.

关键词： strain rote strain shear localization Mg-Li alloy

Recovery of silica from sodium silicate solution of calcined boron mud

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Rare Metals 2016年第2期35卷 204-210页

作者： Zhi-Qiang Ning Yu-chun Zhai Hong-Wei Xie Qiu-shi Song Ka Yu School of Materials and Metallurgy Northeastern University

The effect of several parameters on the recovery of silicon dioxide from calcined boron mud（CBM）such as stirring speed, temperature, sodium silicate concentration, and carbonation time was studied. The recovery of silicon dioxide is 88 % when the stirring speed is450 r min-1, temperature is 60 °C, sodium silicate concentration is 1 mol L-1, and the carbonation time is 6 *** effect of carbonation time on the recovery of silicon dioxide is divided into three kinetic regimes, and the carbonation process of sodium silicate solution follows a second-order reaction based on the double-film theory model. The apparent rate constant of the three kinetic regimes is 0.064, 3.178, and 1.130 L h mol-1, *** amorphous SiO_2 products obtained by carbonating the purified solution have 99.6 % purity and are spherical with diameters of about 100 nm.

关键词： Boron mud Carbonation Recovery Silicon dioxide

Modeling of the whole process of shock wave overpressure of freefield air explosion

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Defence Technology（防务技术） 2019年第5期15卷 815-820页

作者： Zai-qing Xue Shunping Li chun-liang Xin Li-ping shi Hong-bin Wu Beijing Institute of Space Long March Vehicle

The waveform of the explosion shock wave under free-field air explosion is an extremely complex *** is generally considered that the waveform consists of overpressure peak,positive pressure zone and negative pressure *** of current practice usually considers only the positive *** empirical relations are available to predict overpressure peak,the positive pressure action time and pressure decay ***,there are few models that can predict the whole *** whole process of explosion shock wave overpressure,which was expressed as the product of the three factor functions of peak,attenuation and oscillation,was proposed in the present *** to the principle of explosion similarity,the scaled parameters were introduced and the empirical formula was absorbed to form a mathematical model of shock wave *** numerical simulations of free-field air explosions were *** experimental verification of the AUTODYN numerical method and comparing the analytical and simulated curves,the model is proved to be accurate to calculate the shock wave overpressure under free-field air *** addition,through the model the shock wave overpressure at different time and distance can be displayed in three *** model makes the time needed for theoretical calculation much less than that for numerical simulation.

关键词： Air explosion Shock wave overpressure Free field experimental verification Numerical simulation

Nonparametric estimation of Interval-censored Failure Time Data in the Presence of Informative Censoring

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Acta Mathematicae Applicatae Sinica 2017年第1期33卷 107-114页

作者： chun-jie WANG Jian-guo SUN De-hui WANG Ning-zhong shi The College of Basic Science Changchun University of Technology Changchun 130012 China Mathematics School and Institute of Jilin University Changchun 130012 China Department of Statistics University of Missouri 146 Middlebush Hall MO 65211. USA Key Laboratory of Applied Statistics of MOe School of Mathematics and Statistics Northeast Normal University Changchun 130024 China

Nonparametric estimation of a survival function is one of the most commonly asked questions in the analysis of failure time data and for this, a number of procedures have been developed under various types of censoring structures （Kalbfleisch and Prentice, 2002）. In particular, several algorithms are available for interval-censored failure time data with independent censoring mechanism （Sun, 2006; Turnbull, 1976）. In this paper, we consider the interval-censored data where the censoring mechanism may be related to the failure time of interest, for which there does not seem to exist a nonparametric estimation procedure. It is well-known that with informative censoring, the estimation is possible only under some assumptions. To attack the problem, we take a copula model approach to model the relationship between the failure time of interest and censoring variables and present a simple nonparametric estimation procedure. The method allows one to conduct a sensitivity analysis among others.

关键词： copula models interval censored data dependent censoring nonparametric estimation