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Two phase decision algorithm of replica allocation

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Journal of Systems Engineering and Electronics 2006年第1期17卷 206-212页

作者： Zuo Chaoshu liu Xinsong Wang zheng li yi School of Computer Science and Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

In distributed parallel server system, location and redundancy of repficas have great influence on availability and efficiency of the system. In order to improve availability and efficiency of the system, two phase decision algorithm of replica allocation is proposed. The algorithm which makes use of auto-regression model dynamically predicts the future count of READ and WRITE operation, and then determines location and redundancy of replicas by considering availability, CPU and bands of the network. The algorithm can not only ensure the requirement of availability, but also reduce the system resources consumed by all the operations in a great scale. Analysis and test show that communication complexity and time complexity of the algorithm satisfy O（n）, resource optimizing scale increases with the increase of READ count.

关键词： distributed parallel server replica allocation two phase decision performance optimizing

Foxg1 mRNA overexpression in neonatal rats following hypoxic brain injury

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Neural Regeneration Research 2011年第1期6卷 41-46页

作者： Luquan li yi zheng Guoliang Mo Fang li Jialin Yu Neonatal Diagnosis and Treatment Center Children's Hospital of Chongqing Medical University Chongqing 400014 China

Forkhead box G1 （Foxgl） is expressed during the embryonic stage and in postnatal brain regions sensitive to hypoxia/ischemia injury, such as the hippocampus and cerebral cortex. To date, very little is known about Foxgl expression changes in the brain following hypoxia injury （HI）. The present study measured Foxgl mRNA expression using reverse-transcription polymerase chain reaction on days 3, 7, 14, 28, and 56 following HI to determine self-restorative features in the injured brain. In addition, mRNA expression of other related layer markers, such as Reelin, RORB, Foxpl, Foxp2, ER81, and Otx-1, was detected following HI. Results revealed significantly decreased Foxgl mRNA expression at 3 days after HI, which significantly increased by 56 days. Reelin and Foxp2 mRNA expression were upregulated until 56 days after HI, but Foxpl and ER81 mRNA expression decreased from day 14 to 56 following HI. In addition, Otx-1 and RORI3 mRNA expression decreased from day 3 to 28 after HI. These findings revealed Fxogl mRNA overexpression and varying degrees of restoration in the neonatal rat brain following HI.

关键词： Foxgl mRNA hypoxia injury neonatal rats cerebral cortex

Synthesis and Crystal Structure of 1,3-Trans-1,4-cis- 3,4-di(4-bromophenyl)-1',2',3'-trihydro-1-hydroxy- benzo[g]bicyclo[3.3]octane-2-spiro-2'-indene-1'-one

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Chinese Journal of Structural Chemistry 2006年第2期25卷 187-191页

作者： SHI Da-Qing li zheng-yi SHI Chun-ling DOU Guo-Lan Department.of Chemistry Xuzhou Normal University Xuzhou Jiangsu 221116 China Key Laboratory of Biotechnology on Medical Plants of Jiangsu Province Xuzhou 221116 China

The title compound C35H30Br2O3 （C32H24Br2O2·CH3COCH3） has been synthesized by the dimerization of 2-（4＇-bromobenzal）-1-indenone induced by low-valent titanium reagent, and characterized by elemental analysis, IR,^1H NMR and X-ray single-crystal diffraction. The crystal belongs to triclinic, space group P1^- with a = 10.273（7）, b = 11.036（7）, c = 13.944（9） ,A°, a = 73.972（9）, β =76.577（10）,γ= 88.871（10）°, V = 1476.3（17）A°^3, Mr = 658.41, Z = 2, Dr = 1.481 g/cm^3, μ（MoKa） = 2.780 mm^-1, F（000） = 668, the final R = 0.0452 and wR = 0.0975. X-ray analysis reveals that the two cyclopentane rings spiro-fused each other adopt envelope conformations, while the other cyclopentane ring （C（1）--C（2）-C（7）-C（9）） is coplanar. In addition, there is a classical intermolecular hydrogen bond O（1）-H（1）...O（2） connecting the adjacent molecules into dimers.

关键词： benzo[g]bicyclo[3.3]octane-2-spiro-2'-indene-1'-one synthesis crystal structure,low-valent titanium

Chiral thermally activated delayed fluorescence materials for circularly polarized organic light-emitting diodes

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Science China Chemistry 2024年第4期67卷 1097-1116页

作者： li Yuan yi-Pin Zhang You-Xuan zheng State Key Laboratory of Coordination Chemistry Collaborative Innovation Center of Advanced MicrostructuresJiangsu Key Laboratory of Advanced Organic MaterialsSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China

Chirality is an important natural characteristic of organic molecules,and chiral organic molecules have shown extensive application in areas such as pharmaceutical development and material *** from the ability to achieve circularly polarized luminescence(CPL),chiral luminescent materials have shown potential applications in anti-glare display,optical communication and,3D display,*** to the ability to harvest both singlet and triplet excitons by a fast reverse intersystem crossing process without involving noble metals,chiral thermally activated delayed fluorescence(TADF)materials with point chirality,axial chirality,planar chirality and helical chirality are regarded as the state-of-the-art materials for circularly polarized organic light-emitting diodes(CP-OLEDs).In recent years,the chiral TADF materials and CP-OLEDs have rapidly developed,but unfortunately,the dissymmetry factors(g)are far from the requirement of practical *** ideal emitters and devices should have both high efficiency and a g factor,or at least a balance between these two *** review gives an overview of recent progress in chiral TADF materials,with a particular focus on the chiral skeleton,CPL property and device ***,the molecular design concept,device structure and methods to improve the g factors of chiral materials and CP-OLEDs are also discussed.

关键词： chiral thermally activated delayed fluorescence material chiral skeleton circularly polarized luminescence circularly polarized organic light-emitting diodes dissymmetry factor

Relationship between Carotid Atherosclerosis and Cerebral Infarction

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Chinese Medical Sciences Journal 2010年第1期25卷 32-37页

作者： Guang-wen li Guan-yi zheng Jin-guo li Xu-dong Sun Department of Geriatrics Union Hospital Fujian Medical University Fuzhou 350001 China

Objective To study the relationship between carotid atherosclerosis and cerebral infarction (CI). Methods Between November 2008 and March 2009,147 CI patients (CI group) and 48 patients with non-cerebrovascular diseases (control group) were enrolled from inpatients of Neurology Department of our hospital. The diagnostic criterion of thickened carotid intima was set as 1.0 mm≤intima-media thickness (IMT) 0.05). Conclusions Carotid atherosclerosis is to some extent able to reveal the atherosclerotic condition of cerebral arteries and act as an important predictor for the risk of CI. T

关键词： carotid atherosclerosis cerebral infarction intima-media thickness color Doppler ultrasonography

Distributed Economic MPC for Synergetic Regulation of the Voltage of an Island DC Micro-Grid

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 734-745页

作者： yi zheng Yanye Wang Xun Meng Shaoyuan li Hao Chen IEEE the Department of Automation Shanghai Jiao Tong UniversityShanghai 200240 the Key Laboratory of System Control and Information Processing Ministry of Education of ChinaShanghai 200240China Haixi Institutes Chinese Academy of SciencesJinjiang 362216China

In this paper,distributed model predictive control(DMPC) for island DC micro-grids(MG) with wind/photovoltaic(PV)/battery power is proposed,which coordinates all distributed generations(DG) to stabilize the bus voltage together with the insurance of having computational efficiency under a real-time *** on the feedback of the bus voltage,the deviation of the current is dispatched to each DG according to cost over the prediction ***,to avoid the excessive fluctuation of the battery power,both the discharge-charge switching times and costs are considered in the model predictive control(MPC) optimization problems.A Lyapunov constraint with a time-varying steady-state is designed in each local MPC to guarantee the stabilization of the entire *** voltage stabilization of the MG is achieved by this strategy with the cooperation of *** numeric results of applying the proposed method to a MG of the Shanghai Power Supply Company shows the effectiveness of the distributed economic MPC.

关键词： Distributed model predictive control(DMPC) Lyapunovbased model predictive control micro-grid(MG) voltage control

Numerical and experimental study on the falling film flow characteristics with the effect of co-current gas flow in hydrogen liquefaction process

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Petroleum Science 2024年第2期21卷 1369-1384页

作者： Chong-zheng Sun Yu-Xing li Hui Han Xiao-yi Geng Xiao Lu College of Energy Storage Technology Shandong University of Science and TechnologyQingdao 266590ShandongChina College of Pipeline and Civil Engineering/Shandong Provincial Key Laboratory of Oil&Gas Storage and Transportation Safety China University of PetroleumQingdao 266580ShandongChina

liquid hydrogen storage and transportation is an effective method for large-scale transportation and utilization of hydrogen energy. Revealing the flow mechanism of cryogenic working fluid is the key to optimize heat exchanger structure and hydrogen liquefaction process(LH2). The methods of cryogenic visualization experiment, theoretical analysis and numerical simulation are conducted to study the falling film flow characteristics with the effect of co-current gas flow in LH2spiral wound heat *** results show that the flow rate of mixed refrigerant has a great influence on liquid film spreading process, falling film flow pattern and heat transfer performance. The liquid film of LH2mixed refrigerant with column flow pattern can not uniformly and completely cover the tube wall surface. As liquid flow rate increases, the falling film flow pattern evolves into sheet-column flow and sheet flow, and liquid film completely covers the surface of tube wall. With the increase of shear effect of gas-phase mixed refrigerant in the same direction, the liquid film gradually becomes unstable, and the flow pattern eventually evolves into a mist flow.

关键词： Hydrogen liquefaction Spiral wound heat exchanger Flow pattern transition Falling film flow

The Logarithmic Sobolev Inequality for a Submanifold in Manifolds with Nonnegative Sectional Curvature

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Chinese Annals of Mathematics,Series B 2024年第3期45卷 487-496页

作者： Chengyang yi Yu zheng School of Mathematical Sciences East China Normal UniversityShanghai 200241China

The authors prove a sharp logarithmic Sobolev inequality which holds for compact submanifolds without boundary in Riemannian manifolds with nonnegative sectional curvature of arbitrary dimension and *** the Michael-Simon Sobolev inequality,this inequality includes a term involving the mean *** extends a recent result of Brendle with Euclidean setting.

关键词： Logarithmic Sobolev inequality Nonnegative sectional curvature Submanifold

Modification of separators with neodymium oxide/graphene composite to enhance lithium-sulfur battery performance

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Journal of Rare Earths 2024年第9期42卷 1730-1739,I0004页

作者： liyuan zheng Zhijun Zhu Yutong Kuai Qiaotong Huang Mingkun Zhang yi Wang Aiju li School of Chemistry South China Normal UniversityGuangzhou510006China Department of Mechanic and Electronic Engineering Zhongkai University of Agriculture and EngineeringGuangzhou510225China

lithium-sulfur(li-S) batteries have generated significant attention due to their high theoretical specific capacity and energy density among a host of energy storage power ***,the lithium polysulfide dissolution shuttle that occurs within li-S batteries will lead to capacity deterioration and inadequate cycling *** the paper,we proposed a measure to deal with the above problems by modifying the separator with Nd_(2)O_(3)/graphene composite in li-S ***'s special chemical properties and structural qualities make it an excellent choice for li-S ***,Nd_(2)O_(3) has a strong binding affinity with lithium polysulfide due to its low electronegativity,which exhibits Lewis' s acidity and forms strong interactions with lithium polysulfide,which is strongly Lewis *** utilizing these advantageous properties,li-S batteries assembling Nd_(2)O_(3)-decorated reduced graphite oxide modified polypropylene separators(Nd_(2)O_(3)/RGO/PP) demonstrate outstanding electrochemical performance,including a mere 0.0525% capacity attenuation rate under 2C during 1000 cycles and with exceptional rate performance of 614 mAh/g even at *** study presents valuable knowledge for effectively modifying separators using rare earth oxides to incorporate graphene,ultimately promoting the practical application of li-S batteries.

关键词： lithium-sulfur battery Rare earths Neodymium oxide Graphene Modified separator