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SMConf: One-Size-Fit-Bunch, Automated Memory Capacity Configuration for In-Memory Data Analytic Platform

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Computers, Materials & Continua 2021年第2期66卷 1697-1717页

作者： Yi Liang Shaokang Zeng Xiaoxian Xu Shilu Chang xing su Faculty of Information Technology Beijing University of TechnologyBeijing100124China Department of Informatics University of ZurichZurichCH-8050Switzerland

Spark is the most popular in-memory processing framework for big data *** is the crucial resource for workloads to achieve performance acceleration on *** extant memory capacity configuration approach in Spark is to statically configure the memory capacity for workloads based on user’s ***,without the deep knowledge of the workload’s system-level characteristics,users in practice often conservatively overestimate the memory utilizations of their workloads and require resource manager to grant more memory share than that they actually need,which leads to the severe waste of memory *** address the above issue,SMConf,an automated memory capacity configuration solution for in-memory computing workloads in Spark is *** is designed based on the observation that,though there is not one-size-fit-all proper configuration,the one-size-fit-bunch configuration can be found for in-memory computing *** classifies typical Spark workloads into categories based on metrics across layers of Spark system *** each workload category,an individual memory requirement model is learned from the workload’s input data size and the strong-correlated configuration *** an ad-hoc workload,SMConf matches its memory requirement signature to one of the workload categories with small-sized input data and determines its proper memory capacity configuration with the corresponding memory requirement *** results demonstrate that,compared to the conservative default configuration,SMConf can reduce the memory resource provision to Spark workloads by up to 69%with the slight performance degradation,and reduce the average turnaround time of Spark workloads by up to 55%in the multi-tenant environments.

关键词： Spark memory capacity automated configuration

Determination of Trace Amounts of Nickel (Ⅱ) by Graphite Furnace Atomic Absorption Spectrometry Coupled with Cloud Point Extraction

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Chemical Research in Chinese Universities 2011年第3期27卷 366-370页

作者： SHAH Syed Mazhar WANG Hao-nan su xing-guang College of Chemistry Jilin University Changchun 130012 P. R. China College of Environment and Resources Jilin University Changchun 130012 P. R. Chin~

A new method based on the cloud point extraction（CPE） for separation and preconcentration of nickel（Ⅱ） and its subsequent determination by graphite furnace atomic absorption spectrometry（GFAAS） was proposed, 8-hydroxyquinoline and Triton X-100 were used as the ligand and surfactant respectively. Nickel（Ⅱ） can form a hy-drophobic complex with 8-hydroxyquinoline, the complex can be extracted into the small volume surfactant rich phase at the cloud point temperature（CPT） for GFAAS determination. The factors affecting the cloud point extraction, such as pH, ligand concentration, surfactant concentration, and the incubation time were optimized. Under the optimal conditions, a detection limit of 12 ng/L and a relative standard deviation（RSD） of 2.9% were obtained for Ni（Ⅱ） determination. The enrichment factor was found to be 25. The proposed method was successfully applied to the determination of nickel（Ⅱ） in certified reference material and different types of water samples and the recovery was in a range of 95%―103%.

关键词： Cloud point extraction Phase separation Graphite furnace atomic absorption spectrometry Nickel(Ⅱ)

Weakly-solvating electrolytes enable ultralow-temperature (-80°C) and high-power CF_(x)/Li primary batteries

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Science China Chemistry 2023年第7期66卷 1982-1988页

作者： Hao-Jie Liang Meng-Yuan su Xin-Xin Zhao Zhen-Yi Gu Jia-Lin Yang Wei guo Zhi-Ming Liu Jing-Ping Zhang xing-Long Wu MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal UniversityChangchun 130024China Department of Chemistry Northeast Normal UniversityChangchun 130024China Key Laboratory of Organo-Pharmaceutical Chemistry of Jiangxi Province Gannan Normal UniversityGan Zhou 341000China Qingdao University of Science and Technology Qingdao 260061China

Fluorinated carbons(CF_(x))/Li primary batteries with high theoretical energy density have been applied as indispensable energy storage devices with no need for rechargeability,yet plagued by poor rate capability and narrow temperature adaptability in actual ***,benefiting from precise solvation engineering for synergistic coordination of anions and low-affinity solvents,the optimized cyclic ether-based electrolyte is elaborated to significantly facilitate overall reaction dynamics closely correlated to lower desolvation *** a result,the excellent rate(15 C,650 mAh g^(-1))at room-temperature and ultra-lowtemperature performance dropping to-80°C(495 mAh g^(-1)at average output voltage of 2.11 V)is delivered by the end of 1.5 V cut-off voltage,far superior to other organic liquid ***,the CF_(x)/Li cell employing the high-loading electrode(18-22 mg cm^(-2))still yields 1,683 and 1,395 Wh kg^(-1)in the case of-40°C and-60°C,*** short,the novel design strategy for cyclic ethers as basic solvents is proposed to enable the CF_(x)/Li battery with superb subzero performances,which shows great potential in practical application for extreme environments.

关键词： CF_(x)/Li primary batteries solvation engineering desolvation barrier ultra-low temperature

Single and joint stress of acetochlor and Pb on three agricultural crops in northeast China

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Journal of Environmental Sciences 2007年第6期19卷 719-724页

作者： CHAO Lei ZHOU Qi-xing CHEN su CUI Shuang WANG Mei-e Key Laboratory of Terrestrial Ecological Process Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China The Graduate School of Chinese Academy of Sciences Beijing 100039 China College of Environmental Science and Engineering Nankai University lianjin 300071 China

In order to evaluate ecological risk of agrochemicals in agricultural environment, single and joint toxic effects of an important herbicide and a typical heavy metal on root elongation of crops were investigated. Seeds of the three crops including wheat （Triticum aestivum）, Chinese cabbage （Brassica pekimensis） and soybean （Glycine max） as the main crops in northeast China were exposed to acetochior as a herbicide and lead （Pb） as a heavy metal using the pot-culture method, and meadow brown soil as one of the main soils distributed in northeast China was applied in the investigation. The results indicated that the interactive effects of the two pollutants on root elongation of the three crops were very complicated although they had markedly significant （P〈0.01） linear interrelationships based on the regression analyses. When the concentration of added Pb^2＋ reached 200 mg/kg, acetochlor and Pb had an antagonistic effect on the inhibition of root elongation of the three crops. However, acetochlor and Pb had significantly （P〈0.05） synergic effects on the inhibition of root elongation when concentration of added Pb^2＋ was up to 1000 mg/kg. At the low concentration of added Pb, joint toxicity of acetochlor and Pb was more dependent on the concentration of Pb. Among the three crops, wheat was the most sensitive to the toxicity of Pb and Chinese cabbage was the most sensitive to the toxicity of acetochlor.

关键词： acetochlor Pb ecotoxicology joint effect Chinese cabbage (Brassica pekimensis) soybean (Glycine max) wheat (Triticum aestivum)

An experimental study on microscopic characteristics of gas-bearing sediments under different gas reservoir pressures

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Acta Oceanologica Sinica 2021年第10期40卷 144-151页

作者： Zhenqi guo Tao Liu Lei guo Xiuting su Yan Zhang Sanpeng Li Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China Laboratory for Marine Geology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Institute of Marine Science and Technology Shandong UniversityQingdao 266237China College of Marine Geosciences Ocean University of ChinaQingdao 266100China

Gas-bearing sediments are widely distributed in five continents all over the *** of the gases exist in the soil skeleton in the form of discrete large *** existence of gas-phase may increase or decrease the strength of the soil *** far,bubbles’structural morphology and evolution characteristics in soil skeleton lack research,and the influence of different gas reservoir pressures on bubbles are still *** micro characteristics of bubbles in the same sediment sample were studied using an industrial CT scanning test system to solve these *** the image processing software,the micro variation characteristics of gas-bearing sediments in gas reservoir pressure change are *** results show that the number and volume of bubbles in different equivalent radius ranges will change regularly under different gas reservoir *** the increase of gas reservoir pressure,the number and volume of tiny bubbles *** contrast,the number and volume of large bubbles increase,and the gas content in different positions increases and occupies a dominant position,driving the reduction of pore water and soil skeleton movement.

关键词： micro characteristics CT scanning gas content number and volume of bubbles gas reservoir pressure seabed sediments

Construction of porous covalent organic polymer as photocatalysts for RhB degradation under visible light

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Science Bulletin 2017年第13期62卷 931-937页

作者： Pingxiao Liu Lingbao xing Hongtao Lin Haining Wang Ziyan Zhou Zhongmin su School of Chemical Engineering Shandong University of Technology College of Chemistry Northeast Normal University

In the present work, a novel porous, and chemically stable amine-based covalent organic polymer （POP-1） was designed and synthesized under solvothermal conditions. The porosity, crystallinity, chemical stability, electrochemical properties, and diffuse reflectance of POP-1 were investigated via N2 sorp- tion experiment, power X-ray diffraction, thermogravimetric analysis, cyclic voltammetry, and ultraviolet visible near infrared spectrometry, respectively. POP-I exhibits good chemical stability in both acidic and alkaline aqueous solutions, as well as in organic solvents. Undoped POP-1 can be directly used as a pho- tocatalyst for rhodamine B irradiation degradation under light-emitting diode and natural light. The Ea of POP-1 for RhB degradation is 82.37 kJ/mol. Furthermore, POP-1 can be reused as a catalyst in RhB degra- dation without degraded catalytic activity.

关键词： Porous organic polymerMetal-freeSolvothermal synthesisPhotocatalytic degradation

Research on induced pluripotent stem cells and the application in ocular tissues

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International Journal of Ophthalmology(English edition) 2015年第4期8卷 818-825页

作者： Xiao-Ling guo Jian-su Chen Key Laboratory for Regenerative Medicine Ministry of Education Jinan University Eye Institute Medical College of Jinan University Department of Ophthalmology the First Clinical Medical College of Jinan University

·Induced pluripotent stem cells(i PSCs) were firstly induced from mouse fibroblasts since 2006, and then the research on i PSCs had made great progress in the following years. i PSCs were established from different somatic cells through DNA, RNA, protein or small molecule pathways and transduction vehicles. With continuous improvement of technology on reprogramming, the induction of i PSCs became more secure and effective, and showed enormous promise for clinical applications. We reviewed different reprogramming of somatic cells, four kinds of pathways of reprogramming and three types of transduction vehicles, and discuss the research of i PSCs in ophthalmology and the prospect of i PSCs applications.

关键词： induced pluripotent stem cells reprogramming ocular tissues

Analysis of RDSS positioning accuracy based on RNSS wide area differential technique

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Science China(Physics,Mechanics & Astronomy) 2013年第10期56卷 1995-2001页

作者： xing Nan su RanRan ZHOU JianHua HU XiaoGong GONG XiuQiang LIU Li HE Feng guo Rui REN Hui HU GuangMing ZHANG Lei Shanghai Astronomical Observatory Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences Beijing Satellite Navigation Center

The BeiDou Navigation Satellite System(BDS) provides Radio Navigation Service System(RNSS) as well as Radio Determination Service System(RDSS).RDSS users can obtain positioning by responding the Master Control Center(MCC) inquiries to signal transmitted via GEO satellite *** positioning result can be calculated with elevation constraint by *** primary error sources affecting the RDSS positioning accuracy are the RDSS signal transceiver delay,atmospheric trans-mission delay and GEO satellite position *** GEO orbit maneuver,poor orbit forecast accuracy significantly impacts RDSS services.A real-time 3-D orbital correction method based on wide-area differential technique is raised to correct the orbital *** from the observation shows that the method can successfully improve positioning precision during orbital maneuver,independent from the RDSS reference *** improvement can reach 50% in *** calibration of the RDSS signal transceiver delay precision and digital elevation map may have a critical role in high precise RDSS positioning services.

关键词： BeiDou Navigation Satellite System (BDS) RDSS RNSS wide-area differential technique

Chain damage effects of multi-spaced plates by reactive jet impact

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Defence Technology（防务技术） 2021年第2期17卷 393-404页

作者： Yuan-feng Zheng Cheng-hai su Huan-guo guo Qing-bo Yu Hai-fu Wang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

Chain damage is a new phenomenon that occurs when a reactive jet impacts and penetrates multispaced *** reactive jet produces mechanical perforations on the spaced plates by its kinetic energy(KE),and then results in unusual chain rupturing effects and excessive structural damage on the spaced plates by its deflagration *** the present study,the chain damage behavior is initially demonstrated by *** reactive liners,composed of 26 wt%Al and 74 wt%PTFE,are fabricated through a pressing and sintering *** reactive liner thicknesses of 0.08 CD,0.10 CD and 0.12 CD(charge diameter)are chosen to carry out the chain damage *** results show a chain rupturing phenomenon caused by reactive *** constant reaction delay time and the different penetration velocities of reactive jets from liners with different thicknesses result in the variation of the deflagration position,which consequently determines the number of ruptured plates behind the ***,the finite-element code AUTODYN-3D has been used to simulate the kinetic energy only-induced rupturing effects on plates,based on the mechanism of behind armor debris(BAD).The significant discrepancies between simulations and experiments indicate that one enhanced damage mechanism,the behind armor blast(BAB),has acted on the ruptured ***,a theoretical model is used to consider the BAB-induced enhancement,and the analysis shows that the rupturing area on aluminum plates depends strongly upon the KE only-induced pre-perforations,the mass of reactive materials,and the thickness of plates.

关键词： Reactive materials Reactive jet Chain damage Behind armor blast