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Water mass characteristics in the western North Pacific based on a streamfunction projection

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Science China Earth Sciences 2015年第11期58卷 2067-2077页

作者： MA Xiao SUN che Institute of Oceanology Chinese Academy of Sciences College of Earth Sciences University of Chinese Academy of Sciences

A streamfunction projection method called gravest empirical mode(GEM) is applied to the hydrographic section at 137°E to filter out eddy noises in the western North Pacific and derive quantitative ensemble-average water mass properties in the North Equatorial Current region. The GEM fields capture more than 80% of total property variances in the thermocline layer. The core layer structures of key water masses, including the North Pacific Tropical Water(NPTW) and the North Pacific Intermediate Water(NPIW), are examined with a definition of water mass boundary based on property gradient. It shows that a tongue of maximal root-mean-square(RMS) residual exists in the upper half of NPIW for all water properties. These subsurface RMS tongues appear to be close to sharp property gradients. It is the first time a GEM diagnosis is applied to nutrient data, which reveals a drastic difference of N/P reaction rate ratio above and below the maximal-nutrient core at 1250 m. Additionally, a GEM velocity reconstruction successfully produces the North Equatorial Undercurrent(NEUC), demonstrating the stable thermal-wind nature of this newly-discovered current.

关键词： streamfunction projection gravest empirical mode water masses western North Pacific

Influence of Sox protein SUMOylation on neural development and regeneration

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Neural Regeneration Research 2022年第3期17卷 477-481页

作者： Kun-che Chang Department of Ophthalmology Louis J.Fox Center for Vision RestorationUniversity of Pittsburgh School of MedicinePittsburghPAUSA

SRY-related HMG-box(Sox) transcription factors are known to regulate central nervous system development and are involved in several neurological ***-translational modification of Sox proteins is known to alter their functions in the central nervous *** the different types of post-translational modification,small ubiquitin-like modifier(SUMO) modification of Sox proteins has been shown to modify their transcriptional ***,we review the mechanisms of three Sox proteins in neuronal development and disease,along with their transcriptional changes under *** three species,lysine is the conserved residue for *** Drosophila,SUMOylation of Sox N plays a repressive role in transcriptional activity,which impairs central nervous system ***,de SUMOylation of Sox E and Sox11 plays neuroprotective roles,which promote neural crest precursor formation in Xenopus and retinal ganglion cell differentiation as well as axon regeneration in the *** further discuss a potential translational therapy by SUMO site modification using AAV gene transduction and Clustered regularly interspaced short palindromic repeats-Cas9 *** the underlying mechanisms of Sox SUMOylation,especially in the rodent system,may provide a therapeutic strategy to address issues associated with neuronal development and neurodegeneration.

关键词： axon regeneration neural development neurological disorder neuroprotection post-translational modification small ubiquitin-like modifier Sox transcription factor SUMOylation

Word sense disambiguation using semantic relatedness measurement

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第10期7卷 1609-1625页

作者： YANG che-Yu Department of Computer Science and lnformation Engineering Tamkang University Taipei 25137 Taiwan China

All human languages have words that can mean different things in different contexts, such words with multiple meanings are potentially “ambiguous”. The process of “deciding which of several meanings of a term is intended in a given context” is known as “word sense disambiguation (WSD)”. This paper presents a method of WSD that assigns a target word the sense that is most related to the senses of its neighbor words. We explore the use of measures of relatedness between word senses based on a novel hybrid approach. First, we investigate how to “literally” and “regularly” express a “concept”. We apply set algebra to WordNet’s synsets cooperating with WordNet’s word ontology. In this way we establish regular rules for constructing various representations (lexical notations) of a concept using Boolean operators and word forms in various synset(s) defined in WordNet. Then we establish a formal mechanism for quantifying and estimating the semantic relatedness between concepts—we facilitate “concept distribution statistics” to determine the degree of semantic relatedness between two lexically expressed con- cepts. The experimental results showed good performance on Semcor, a subset of Brown corpus. We observe that measures of semantic relatedness are useful sources of information for WSD.

关键词： Word sense disambiguation (WSD) Semantic relatedness WordNet Natural language processing

Coded Modulation Faster-than-Nyquist Transmission with Precoder and Channel Shortening Optimization

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China Communications 2021年第2期18卷 49-64页

作者： Hui che Yong Bai School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China School of Information and Communication Engineering Hainan UniversityHaikou 570228China

Faster-than-Nyquist(FTN)signaling can improve the spectrum efficiency(SE)of the transmission *** this paper,we propose a coded modulation FTN(CM-FTN)transmission scheme with precoder and channel shortening(CS)optimization to improve bit error rate(BER)performance and reduce the complexity of FTN *** our proposal,the information rate(IR)or spectral efficiency(SE)is employed and verified as a better performance metric for CM-FTN than the minimum Euclidian distance(MED).The precoder of CM-FTN is optimized for maximizing the IR criterion using the bare-bones particle swarm optimization(BB-PSO)***,a three-carrier CM-FTN system model is used to capture the broadening effect of *** targeting for the IR maximization,the inter-symbol interference(ISI)length for CS is optimized to reduce the receiver complexity without performance *** results demonstrate that our method has a 0.6dB precoding gain compared with the nonprecoding scheme and a maximum of 87.5%of the complexity of FTN equalizer is reduced without BER loss.

关键词： faster-than-Nyquist coded modulation information rate minimum Euclidian distance precoder channel shortening

M-BCJR Algorithm with Channel Shortening Based on Ungerboeck Observation Model for Faster-than-Nyquist Signaling

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China Communications 2021年第4期18卷 88-98页

The M-BCJR algorithm based on the Ungerboeck observation model is a recent study to reduce the computational complexity for faster-than-Nyquist(FTN)signaling[1].In this paper,we propose a method that can further reduce the complexity with the approximately same or better bit error rate(BER)performance compared to[1].The information rate(IR)loss for the proposed method is less than 1%compared to the true achievable IR(AIR).The proposed improvement is mainly by introducing channel shortening(CS)before the M-BCJR *** our proposal,the Ungerboeck M-BCJR algorithm and CS can work together to defeat severe inter-symbol interference(ISI)introduced by FTN *** ISI length for the M-BCJR algorithm with CS is optimized based on the criterion of the IR *** the two cases=0.5 and=0.35,compared to Ungerboeck M-BCJR without CS benchmark[1],the computational complexities of Ungerboeck M-BCJR with CS are reduced by 75%.Moreover,for the case=0.35,the BER performance of Ungerboeck M-BCJR with CS outperforms that of the conventional M-BCJR in[1]at the low signal to noise ratio region.

关键词： M-BCJR Ungerboeck model channel shortening FTN reduced-complexity turbo equalization

Mesoporous Silica Microspheres Composited with SBA-15s for Resonance Frequency Reduction in a Miniature Loudspeaker

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chemical Research in Chinese Universities 2020年第5期36卷 760-767页

作者： ZHANG Xinyue che Shunai School of chemistry and chemical Engineering State Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai 200240P.R.China

Microspheres composited with mesoporous SBA-15 particles and silica were investigated as fillers in miniature loudspeakers to study the factors influencing the resonance frequency offsets(RFOs).Mesoporous silica microspheres(MSMs)were prepared by self-assembling SBA-15 mesoporous silica in a microemulsion synthesis *** formation process involved the fabrication of a stable O/W microemulsion of tetrabutyl orthosili-cate(TBOS)and hexadecyltrimethylammonium bromide(C16TAB)and encapsulation of *** RFO increased and then decreased with increasing particle size(in the length range of 0.7—5.5 μm and in the width range of 0.2—0.45 μm),increased with increasing pore size(in the range of 7.0—9.4 nm)of SBA-15s,and increased with decreasing particle size(105—900 μm)of MSMs.

关键词： Mesoporous silica microsphere Microemulsion SBA-15 Resonance frequency offset

Density fluctuations in baryon-rich quark matter

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Nuclear Science and Techniques 2016年第6期27卷 17-24页

作者： che Ming Ko Feng Li Cyclotron Institute and Department of Physics and Astronomy Texas A&M UniversityCollege Station

At finite baryon chemical potential,the density of a quark matter develops large fluctuations when it undergoes a first-order phase *** on the transport equation derived from the Nambu–Jona-Lasinio(NJL) model,we have studied the density fluctuations in a baryon-rich quark matter that is confined in a finite *** the expansion of the quark matter using initial conditions from either a blast wave model or a multiphase transport(AMPT) model,we have further studied the survivability of the density fluctuations as the density and temperature of the quark matter *** experimental signatures of the density fluctuations are suggested.

关键词：密度涨落夸克物质重子输运方程一级相变体积密度 AMPT 可生存性

THE　STUDY　ON　EFFECT　OF　PARTICLE　SIZE　IN　BOTANICAL　STANDARD　SAMPLE　ANALYSIS　BY　SLURRY　SAMPLING　AND　FLUORINATION　ELECTROTHERMAL　VAPORIZATION（ETV）－ICP－AES

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Chinese chemical Letters 1995年第4期6卷 325-326页

作者： Qin, YC Jiang, zc Zeng, YE Hu, B Wuhan Univ Dept Chem Wuhan 430072 Peoples R China

In this paper, the effect of partical size, in fluorination assisted ETV-ICP-AES. The results experimental show that when the pertical size of slurry samples is less than 170μm, the signal intensities of analytes were identical to those obtained with aqueous solutions. Comparing with the data given by slurry nebulization ICP-AES in literature, the tolerable particle size in this method is large by about 17-fold.

关键词： AES ICP ANALYSIS ETV

The lipase monolayer film self-assembly on the negatively charged poly(ethylene terephthalate) substrate

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Chinese chemical Letters 2000年第3期11卷 267-270页

作者： Lin, XF He, L Xu, LH Lu, DS chen, zc Zhejiang Univ Ctr Anal & Measurement Hangzhou 310027 Peoples R China

The PET-CO2- film was prepared and the lipase was assembled on the surface of the PET-CO2- substrate The structure at the surface and activity of lipase/PET monolayer were studied by ATR-FTIR and AFM, and other methods.

关键词： self-assembled monolayer lipase PET-CO2 substrate