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Journal of Genetics and Genomics 2023年第6期50卷 447-449页

作者： Jinhui Kong shuo zhang Wenfeng Qian Ke Li State Key Laboratory of Plant Genomics Institute of Genetics and Developmental BiologyInnovation Academy for Seed DesignChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Synonymous mutations are mutations that occur in the coding sequence of a gene but do not change the amino acid sequence of the encoded *** is now understood that synonymous mutations can have a variety of functional ... 详细信息

关键词： consequences neutral frame

An overview of multi-antenna technologies for space-ground integrated networks

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Science China Earth Sciences 2016年第12期59卷 1-18页

作者： Lei GAO shuo zhang Ziyao LIU Jinyong LIN Shuai WANG Chengwen XING National Key Laboratory of Science and Technology on Aerospace Intelligence Control Beijing 100854China Beijing Aerospace Automatic Control Institute Beijing 100854China School of Information Science and Electronics Beijing Institute of TechnologyBeijing 100081China

Multi-antenna technologies have already achieved a series of great successes in the development of information networks. For future space-ground integrated networks(SGINs), the traditional various kinds of separated information networks will converge to a whole fully connected information network to provide more flexible and reliable services on a world scale. Regarding their great successes in existing systems, multiantenna technologies will be of critical importance for the realization of SGINs and multi-antenna technologies are definitely one of the most important enabling technologies for future converged SGINs. In this article, a comprehensive overview on multi-antenna technologies is given. We first investigate multi-antenna technologies from a theoretical viewpoint. It is shown that we can understand multi-antenna technologies in a general and unified point of view. This fact has two-fold meanings. First, the research on multi-antennas can help us understand the relationships between different technologies e.g., OFDMA, CDMA, etc. On the other hand,multi-antenna technologies are easy to integrate into various information systems. Following that, we discuss in depth the potentials and challenges of the multi-antenna technologies on different platforms and in different applications case by case. More specifically, we investigate spaceborne multi-antenna technologies, airborne multi-antenna technologies, shipborne multi-antenna technologies, etc. Moreover, the combinations of multiantenna technologies with other advanced wireless technologies e.g., physical layer network coding, cooperative communication, etc., are also elaborated.

关键词： MIMO multi-antenna technologies signal processing space-ground integrated networks satellite networks terrestrial networks

Analysis and synchronization controller design of dual-port gridforming voltage-source converters for different operation modes

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iEnergy 2024年第1期3卷 46-58页

作者： shuo zhang Wei Qiao Liyan Qu Jun Wang Department of Electrical and Computer Engineering University of Nebraska-LincolnLincolnNE 68588-0511USA

Grid-tie voltage source converters(VSCs)can operate in three distinct modes:AC-dominant,DC-dominant,and balanced,depending on the placement of the stiff voltage *** distinct operation modes of the VSCs traditionally demand different synchronization control techniques,leading to heterogeneous *** is challenging for the power system to accommodate and coordinate heterogeneous VSCs.A promising universal synchronization control technique for VSCs is the DC-link voltage synchronization control(DVSC)based on a lead compensator(LC).The LC DVSC stabilizes both the DC and AC voltages of a VSC while achieving synchronization with the AC *** results in a dual-port grid-forming(DGFM)characteristic for the ***,there has been very limited study on the stability and synchronization controller design of the VSCs with the LC DVSC operating in various *** bridge this gap,the paper presents a quantitative analysis on the stability and steady-state performance of the LC DVSC in all three operation modes of the DGFM *** on the analysis,the paper provides step-by-step design guidelines for the LC ***,the paper uncovers an instability issue related to the LC DVSC when the DGFM VSC operates in the balanced *** tackle the instability issue,a virtual resistance control is proposed and integrated with the LC *** results validate the analysis and demonstrate the effectiveness of the DGFM VSC with the LC DVSC designed using the proposed guidelines in all three operation ***,the paper demonstrates the feasibility of employing the DGFM VSC with the LC DVSC for all three possible operation modes,which can help overcome the challenges associated with accommodating and coordinating heterogeneous VSCs in the power system.

关键词： DC-link voltage synchronization control(DVSC) dual-port grid-forming(DGFM)control grid forming(GFM) synchronization stability voltage-source converter(VSC)

Al–9.00 %Si–0.25 %Mg alloys modified by ytterbium

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Rare Metals 2017年第2期36卷 95-100页

作者： Kun Jia Wen-Bin Yu Jian-Min Yao shuo zhang Hao Wu School of Materials Science and Engineering Southwest University Guangzhou Automobile Group Motor Co Ltd

The effects of ytterbium（Yb） on microstructure and solidification behavior of Al-9.00%Si-0.25%Mg alloys were *** optical microscope（OM） and scanning electron microscopy（SEM）,it is found that the morphology of eutectic silicon changes from coarse plates to fine fibers by the addition of 0.7%wt *** addition,the grains of α-Al matrix are refined by Yb *** constitution of the alloy was analyzed by X-ray diffractometer（XRD） and energy dispersive spectroscopy（EDS）attached with SEM and mechanical properties were measured by hardness *** is concluded that the Yb atoms are incorporated into the silicon by the adsorption at the solid-liquid growth front to cause the modification of eutectic ***,the results of XRD and EDS analysis reveal that the Yb-containing phase forming in the alloys is Al_3Yb.

关键词： Al-9.00 %Si-0.25 %Mg alloy Yb Modification Eutectic silicon

Statistical Modeling of the High Altitude Platform Dual-Polarized MIMO Propagation Channel

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China Communications 2017年第3期14卷 43-54页

作者： Mingchuan Yang shuo zhang Xinye Shao Qing Guo Wenyan Tang Communication Research Center Harbin Institute of Technology Harbin 150080 China Instrument Science and Technology postdoctoral Station Harbin Institute of Technology

In order to investigate the benefit of multiple-input multiple-output(MIMO) technique applying to the high altitude platform(HAP), a 2×2 MIMO statistical model, which can accurately describe the channel between HAP and high-speed train, is presented. And dual polarization diversity is particularly considered. Based on first-order three-state Markov chain, the single-input single-output(SISO) channel, a subset of the MIMO channel is first established. The ray tracing approach applied to the digital relief model(DRM) which covers the railway between Xi'an and Zhengzhou is used to obtain the state probability vector and matrix of the state transition probability. The proposed model considers both Doppler shift and temporal correlation, and the polarization correlation and spatial correlation statistical properties of large-scale fading and smallscale fading are analyzed. Moreover, useful numerical results on the MIMO HAP channel outage capacity are provided based on which, significant capacity gains with respect to the conventional SISO case are illustrated. Such statistical channel model can be applied to the future wireless communication system between HAP and high-speed train.

关键词： high altitude platform(HAP) channel model multiple-input multiple-output(MIMO) polarization diversity

Run-Time Dynamic Resource Adjustment for Mitigating Skew in MapReduce

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Computer Modeling in Engineering & Sciences 2021年第2期126卷 771-790页

作者： Zhihong Liu shuo zhang Yaping Liu Xiangke Wang Dong Yin College of Intelligence and Technology National University of Defense TechnologyChangsha410073China Cyberspace Institute of Advanced Technology Guangzhou UniversityGuangzhou510006China

MapReduce is a widely used programming model for large-scale data ***,it still suffers from the skew problem,which refers to the case in which load is imbalanced among *** problem can cause a small number of tasks to consume much more time than other tasks,thereby prolonging the total job completion *** solutions to this problem commonly predict the loads of tasks and then rebalance the load among ***,solutions of this kind often incur high performance overhead due to the load prediction and ***,existing solutions target the partitioning skew for reduce tasks,but cannot mitigate the computational skew for map ***,in this paper,we present DynamicAdjust,a run-time dynamic resource adjustment technique for mitigating *** than rebalancing the load among tasks,DynamicAdjust monitors the run-time execution of tasks and dynamically increases resources for those tasks that require more *** so doing,DynamicAdjust can not only eliminate the overhead incurred by load prediction and rebalancing,but also culls both the partitioning skew and the computational *** are conducted based on a 21-node real cluster using real-world *** results show that DynamicAdjust can mitigate the negative impact of the skew and shorten the job completion time by up to 40.85%.

关键词： MapReduce task scheduling resource allocation data skew big data

Ultra-early amplitude decrement after repetitive nerve stimulation supports early neuromuscular junction injury in amyotrophic lateral sclerosis:a prospective cross-sectional study

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Neural Regeneration Research 2022年第3期17卷 655-660页

作者： Jing-Yue Ma Xiang-Yi Liu shuo zhang Dong-Sheng Fan Department of Neurology Peking University Third HospitalBeijingChina Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases BeijingChina

The dying-back hypothesis holds that the damage to neuromuscular junctions and distal axons in amyotrophic lateral sclerosis occurs at the earliest stage of the *** basic studies have confirmed early damage to neuromuscular junctions,but it is difficult to obtain such evidence directly in clinical *** this prospective cross-sectional study,we recruited 22 patients with early amyotrophic lateral sclerosis with disease duration < 12 months and with clinical symptoms limited to the upper *** also recruited 32 healthy *** nerve stimulation was performed,and patients were followed for 12 *** found a significant change in the response to repetitive nerve stimulation in amyotrophic lateral sclerosis patients without spontaneous electromyographic *** that were prone to denervation had an increased decrement response of target muscles after repetitive nerve *** results suggest that changes in response to repetitive nerve stimulation may occur before denervation in amyotrophic lateral sclerosis *** damage to lower motor neurons is more obvious in patients with a higher percentage of repetitive never stimulation-related amplitude *** study was approved by the Institutional Ethics Committee of Peking University Third Hospital(approval No.M2017198) on August 24,2017.

关键词： amplitude decremental response amyotrophic lateral sclerosis dying-back hypothesis motor neuron disease nerve electrophysiology physiopathology prognosis repetitive nerve stimulation

Recent Advances of the Combination of Au/Acid Catalysis

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Chinese Journal of Chemistry 2014年第10期32卷 937-956页

作者： shuo zhang Fang Wei Chuangling Song Jiong Jia Zhenghu Xu Key Lab for Colloid and Interface Chemistry of Education Ministry School of Chemistry and Chemical EngineeringShandong UniversityJinanShandong 250100China

Recently,homogeneous gold catalysis has attracted tremendous attention and has also been widely used in multistep *** current reaction methodology starts from the gold activation of unsaturated carbon bond and subsequent nucleophilic *** combination of a gold catalyst with another acid catalyst,including Brønsted acid and Lewis acid,is possible to bring two distinctive catalytic systems together and deliver unprecedented new *** essentially,it avoids the purification of unstable intermediates and improves the step and atom ***,the recent progress in the Au/Acid combined catalysis is reviewed,including the scope of reactions,mechanism and synthetic applications.

关键词： Au catalyst Brønsted acid Lewis acid relay catalysis Tandem reaction

Elastoplastic Model for Soils Considering Structure and Overconsolidation

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Journal of Shanghai Jiaotong university(Science) 2019年第2期24卷 196-203页

作者： zhang shuo LIAO Chencong zhang Qi ZHEN Liang Department of Civil Engineering Shanghai Jiao Tong University Shanghai Road and Bridge (Group) Co. Ltd.

An isotropic hardening elastoplastic model for soil is presented, which takes into consideration the influence of structure and overconsolidation on strength and deformation of clays. Based on the superloading concept and subloading concept, the inner structural variable ω and overconsolidation variable ρ are introduced to describe the structure and overconsolidation of soil. The present model requires three additional parameters which can be obtained by conventional triaxial test, and the other parameters are same as those of modified Cam-clay(MCC) model. The performance of the proposed model is verified by undrained and drained triaxial tests.

关键词： elastoplastic model clay overconsolidation structure transformed stress

The SmNPR4-SmTGA5 module regulates SA-mediated phenolic acid biosynthesis in Salvia miltiorrhiza hairy roots

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Horticulture Research 2023年第5期10卷 260-270页

作者： Meiling Ding Bin zhang shuo zhang RongRong Hao Yu Xia Pengda Ma Juane Dong College of Life Sciences Northwest A&F UniversityYangling 712100China

Phenolic acids are the main bioactive compounds in Salvia miltiorrhiza,which can be increased by salicylic acid(SA)***,the specific molecular mechanism remains *** nonexpresser of PR genes 1(NPR1)and its family members are essential components of the SA signaling ***,we report an NPR protein,SmNPR4,that showed strong expression in hairy root after SA treatment,acting as a negative moderator of SA-induced phenolic acid biosynthesis in ***(***).Moreover,a basic leucine zipper family transcription factor SmTGA5 was identified and was found to interact with ***5 activates the expression of phenolic acid biosynthesis gene SmTAT1 through binding to the as-1 ***,a series of biochemical assays and dual gene overexpression analysis demonstrated that the SmNPR4 significantly inhibited the function of SmTGA5,and SA can alleviate the inhibitory effect of SmNPR4 on ***,our results reveal the molecular mechanism of salicylic acid regulating phenolic acid biosynthesis in *** and provide new insights for SA signaling to regulate secondary metabolic biosynthesis.

关键词： element phenolic roots