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A reduction scheme of PAPR in CO-OFDM system using time-delay neural networks

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Optoelectronics Letters 2025年

作者： TONG zhengrong liu Zhihong WANG Hao zhang Weihua zhang Tianhao JIA Qiqi Tianjin Key Laboratory of Thin Film Electronics and Communication Devices， Engineering Research Center for Optoelectronic Devices and Communication Technology of the Ministry of Education， School of Integrated Circuit Science and Engineering， Tianjin University of Technology

An iterative partial transmission sequence （IPTS） cascading time-delay neural network （TDNN） scheme is proposed to reduce peak-to-average power ratio （PAPR） in the coherent optical orthogonal frequency division multiplexing （CO-OFDM） systems. The IPTS algorithm further reduces computational complexity based on the partial transmission sequence （PTS） algorithm. TDNN is trained by the iterative clipping filtering （ICF） method. Simulation results show that the proposed scheme achieves a PAPR reduction of 5.84 dB when complementary cumulative distribution function （CCDF） is 10-4and an extra transmission distance of 200 km for 10-3bit error rate （BER） compared to the original signals.

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Phenology of different types of vegetation and their response to climate change in the Qilian Mountains,China

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Journal of Mountain Science 2024年第2期21卷 511-525页

作者： ZHAO Kaixin LI Xuemei zhang zhengrong liu Xinyu Faculty of Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China National-Local Joint Engineering Research Center of Technologies and Applications for National Geographic State Monitoring Lanzhou 730070China Gansu Provincial Engineering Laboratory for National Geographic State Monitoring Lanzhou 730070China

The Qilian Mountains(QM)possess a delicate vegetation ecosystem,amplifying the evident response of vegetation phenology to climate *** relationship between changes in vegetation growth and climate remains *** this end,we used MODIS NDVI data to extract the phenological parameters of the vegetation including meadow(MDW),grassland(GSD),and alpine vegetation(ALV))in the QM from 2002 to ***,we employed path analysis to reveal the direct and indirect impacts of seasonal climate change on vegetation ***,we decomposed the vegetation phenology in a time series using the trigonometric seasonality,Box-Cox transformation,ARMA errors,and Trend Seasonal components model(TBATS).The findings showed a distinct pattern in the vegetation phenology of the QM,characterized by a progressive shift towards an earlier start of the growing season(SOS),a delayed end of the growing season(EOS),and an extended length of the growing season(LOS).The growth cycle of MDW,GSD,and ALV in the QM species is clearly *** SOS for MDW and GSD occurred earlier,mainly between late April and August,while the SOS for ALVs occurred between mid-May and mid-August,a one-month delay compared to the other *** EOS in MDW and GSD were concentrated between late August and April and early September and early January,*** phenology exhibits distinct responses to seasonal temperature and precipitation *** advancement and delay of SOS were mainly influenced by the direct effect of spring temperatures and precipitation,which affected 19.59%and 22.17%of the study area,*** advancement and delay of EOS were mainly influenced by the direct effect of fall temperatures and precipitation,which affected 30.18%and 21.17%of the area,*** the contrary,the direct effects of temperature and precipitation in summer and winter on vegetation phenology seem less noticeable and were mainly influenced by indirect *** indirec

关键词： Vegetation phenology Time series decomposition Path Analysis Climate change

Effects of V Addition on Microstructural Evolution and Mechanical Properties of AlCrFe_(2)Ni_(2) High‑Entropy Alloys

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Acta Metallurgica Sinica(English Letters) 2023年第3期36卷 391-404页

作者： Shougang Duan Qian zhang Wenxuan Li Yong Dong Beibei Jiang Shichao liu Chuanqiang Li zhengrong zhang School of Materials and Energy Guangdong University of TechnologyGuangzhou 510006China GDUT Analysis and Test Center Guangdong University of TechnologyGuangzhou 510006China School of Tron and Steel Soochow UniversitySuzhou 215021China

The effects of vanadium addition on the microstructural evolution and mechanical properties of AlCrFe_(2)Ni_(2) high-entropy alloy(HEA)were *** results showed that the AlCrFe_(2)Ni_(2)V_(0.2) HEA was composed of FCC phase,disordered BCC phase,and ordered BCC(B2)*** the increase in vanadium content,the formation of FCC phase was inhibited,and a transition from FCC phase to BCC phase *** FCC phase disappeared completely when the value of x exceeds 0.4 in AlCrFe_(2)Ni_(2)V_(x) ***,the amplitude-modulated microstructure morphology transformed from a B2 phase matrix with dispersed BCC nano-phase into an alternating interconnected B2 and BCC *** element has the function of stabilizing BCC phase and B2 phase in AlCrFe_(2)Ni_(2)V_(x) *** hardness of AlCrFe_(2)Ni_(2)V_(x) alloys increased from HV 332.4 to HV 590.7,while the yield strength increased from 765 to 1744.6 MPa with increasing vanadium content,which was mainly due to the decreasing content of FCC phase and the solid solution strengthening of vanadium *** the same time,the compression ratio of the alloys decreased with the disappearance of the FCC *** the alloys,the AlCrFe_(2)Ni_(2)V_(0.2) alloy possessed the most excellent comprehensive mechanical properties with yield strength,fracture strength,and compressive ratio 1231.1,2861.9 MPa,and 44.5%,respectively.

关键词： High-entropy alloys Microstructure Phase transformation Mechanical properties Solid solution strengthening

Accurate Source-Receiver Positioning Method for a High-Resolution Deep-Towed Multichannel Seismic Exploration System

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Journal of Ocean University of China 2024年第2期23卷 415-426页

作者： LI Jing liu Kai WEI zhengrong zhang Liancheng liu Yangting PEI Yanliang liu Chenguang liu Baohua Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMNRQingdao 266061China Laboratory for Marine Geology Laoshan LaboratoryQingdao 266061China College of Ocean Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou 310018China

The near-seabed multichannel seismic exploration systems have yielded remarkable successes in marine geological disaster assessment,marine gas hydrate investigation,and deep-sea mineral exploration owing to their high vertical and horizontal ***,the quality of deep-towed seismic imaging hinges on accurate source-receiver positioning *** light of existing technical problems,we propose a novel array geometry inversion method tailored for high-resolution deep-towed multichannel seismic exploration *** method is independent of the attitude and depth sensors along a deep-towed seismic streamer,accounting for variations in seawater velocity and seabed slope *** approach decomposes the towed line array into multiline segments and characterizes its geometric shape using the line segment distance and pitch *** optimization parameters for seawater velocity and seabed slope angle,we establish an objective function based on the model,yielding results that align with objective *** the particle swarm optimization algorithm enables synchronous acquisition of optimized inversion results for array geometry and seawater *** validation using theoretical models and practical data verifies that our approach effectively enhances source and receiver positioning inversion *** algorithm exhibits robust stability and reliability,addressing uncertainties in seismic traveltime picking and complex seabed topography conditions.

关键词： high-resolution deep-towed multichannel seismic exploration source-receiver positioning array geometry inversion seawater heterogeneity seabed slope angle

Preferential transport activity of Dk DTX5/MATE5 affects the formation of different astringency in persimmon

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Journal of Integrative Plant Biology 2023年第10期65卷 2304-2319页

作者： Ying liu Xin Wu Chenfeng Sun Wenxing Chen Meng zhang Niannian liu Qinglin zhang Liqing Xu zhengrong Luo National Key Laboratory for Germplasm Innovation&Utilization of Horticultural Crops Huazhong Agricultural UniversityWuhan 430070China

Proanthocyanidins(PAs) are specialized metabolites that infuence persimmon fruit *** astringent(A)-type and non-astringent(NA)-type mutants show significant variation in PA accumulation, but the infuencing mechanism remains unclear. In this study, among the six identified DTXs/MATEs proteins associated with PA accumulation, we observed that allelic variation and preferential transport by Dk DTX5/MATE5 induced variation in PA accumulation for A-type and NA-type fruit. The expression pattern of Dk DTX5/MATE5 was correlated with PA accumulation in NA-type fruit. Upregulation and downregulation of Dk DTX5/MATE5 promoted and inhibited PA accumulation, respectively, in the NA-type fruit. Interestingly, transporter assays of Xenopus laevis oocytes indicated that Dk DTX5/MATE5 preferentially transported the PA precursors catechin, epicatechin, and epicatechin gallate, resulting in their increased ratios relative to the total PAs, which was the main source of variation in PA accumulation between the A-type and NA-type. The allele lacking Ser-84 in Dk DTX5/MATE5 was identified as a dominantly expressed gene in the A-type and lost its transport function. Site-directed mutagenesis revealed that Dk DTX5/MATE5 binds to PA precursors via Ser-84. These findings clarify the association between the transporter function of Dk DTX5/MATE5 and PA variation, and can contribute to the breeding of new cultivars with improved fruit quality.

关键词： astringency DTX/MATE persimmon(Diospyros kaki Thunb.) proanthocyanidins(PAs) tonoplast transmembrane

Unraveling the interfacial effect of PdBi bimetallic catalysts on promoting CO_(2)electroreduction to formate

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Nano Research 2023年第8期16卷 10822-10831页

作者： Wenhui liu Lingtong Ding Minmin liu Xiao Wang zhengrong zhang Tian-Wen Jiang Shengjuan Huo Wen-Bin Cai International Joint Laboratory of Catalytic Chemistry Department of ChemistryInstitute for Sustainable EnergyCollege of SciencesShanghai UniversityShanghai 200444China Shenzhen Key Laboratory of Nanobiomechanics Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Paul C.Lauterbur Research Center for Biomedical Imaging Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Collaborative Innovation Center of Chemistry for Energy MaterialsDepartment of ChemistryFudan UniversityShanghai 200438China

Through interface engineering and content control strategy,a PdBi bimetallic interface structure was constructed for the first time to selectively convert CO_(2)to formate with a remarkably high Faraday efficiency(FEformate)of 94%and a partial current density(jformate)of 34 mA·cm^(−2)at−0.8 V *** hydrogen electrode(RHE)in an ***,the PdBi interface electrocatalyst even exhibited a high current density of 180 mA·cm^(−2)with formate selectivity up to 92%in a flow cell and could steadily operate for at least 20 *** in-situ attenuated total reflection surface enhanced infrared absorption spectroscopy(ATR-SEIRAS)confirmed that the PdBi interface could greatly weaken the adsorption of*CO intermediates due to electronic and geometric *** functional theory(DFT)calculations also established that the PdBi interface regulated the CO_(2)-to-formate pathway by reducing the energy barrier toward HCOOH and largely weakening the adsorption of*CO intermediates on the catalyst *** study reveals that the unique PdBi bimetallic interface can provide a novel platform to study the reaction mechanism through combining in-situ ATR-SEIRAS and DFT calculations.

关键词： carbon dioxide reduction reaction bimetallic PdBi interface engineering formate in-situ attenuated total reflection surface enhanced infrared absorption spectroscopy(ATR-SEIRAS)

Molecular Cloning,Characterization and Expression Profile of Myf5 and Myf6 During Growth and Development in the Seriola lalandi

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Journal of Ocean University of China 2021年第6期20卷 1597-1605页

作者： SHI Bao SUN Ranran liu Xuezhou zhang zhengrong XU Yongjiang JIANG Yan WANG Bin Key Laboratory of Sustainable Development of Marine Fisheries Ministry of Agriculture and Rural AffairsYellow Sea Fisheries Research InstituteChinese Academy of Fishery SciencesQingdao 266071China Laboratory for Marine Fisheries and Food Production Processes Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China College of Fisheries and Life Science Dalian Ocean UniversityDalian 116023China

Myogenic Regulatory Factors(MRFs)is involved in the muscle growth and *** this study,the cDNA sequence of yellowtail kingfish MRFs genes were cloned by rapid amplification of cDNA ends(RACE)method;then,the character-istics of these genes and the predicted protein sequences were analyzed by bioinformatics methods,the tissue and embryonic stages differential expression pattern were detected by the quantitative real-time *** results showed that the yellowtail kingfish(YTK)Myf5 cDNA has a full length of 951 bp,encoding 266 amino *** yellowtail kingfish Myf6 cDNA has a full length of 1105bp,encoding 250 amino *** proteins containα-helix,β-strand,and *** Neighbour-joining tree revealed that YTK Myf5 and Myf6 are closely related to Seriola *** yellowtail kingfish Myf5 and Myf6 gene expressed significantly higher in mus-cle than in other tissues(P<0.05).In addition,Myf5 and Myf6 in muscle was significantly expressed in 400g and 500 g fish but not in 50 g,suggesting that myogenic regulatory factors expression had a great relationship with the fish *** results also indicated that Myf5 and Myf6 have different functions during embryonic development,because Myf5 showed highest expression level at the neuroembryo period,but Myf6 had the highest expression level at embryo coverage yolk 70%***5 gene showed highest ex-pression at 30 d of age,suggesting it played key roles in myogenic ***,the Myf6 gene was significantly highly ex-pressed at 60 d,revealing this gene functioned in the later muscle formation period.

关键词： Seriola lalandi myogenic regulatory factors gene cloning expression

Novel pre-vascularized tissue-engineered dermis based on stem cell sheet technique used for dermis-defect healing

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Regenerative Biomaterials 2020年第6期7卷 627-638页

作者： Zengjie Fan Xuzhuzi Xie Shengqian Zhu Xiaozhu Liao zhengrong Yin Yujue zhang Fengzhen liu School of Stomatology Lanzhou UniversityDonggang West Road 199Gansu 730000People’s Republic of China Liaocheng People’s Hospital Medical College of Liaocheng UniversityLiaocheng 252000People’s Republic of China

Insufficient donor dermis and the shortage of three-dimensional vascular networks are the main limitations in the tissue-engineered dermis(TED).To solve these problems,we initially constructed pre-vascularized bone marrow mesenchymal stem cell sheet(PBMCS)and pre-vascularized fibroblasts cell sheet(PFCS)by cell sheet technology,and then superimposed or folded them together to construct a pre-vascularized TED(PTED),aiming to mimic the real dermis *** constructed PTED was implanted in nude mice dorsal dermis-defect wound and the wound-healing effect was quantified at Days 1,7 and 14 via the methods of histochemistry and *** results showed that PTED could rapidly promote the wound closure,especially at Day 14,and the wound-healing rate of three-layer PTED could reach 97.2%(P<0.01),which was faster than the blank control group(89.1%),PBMCS(92.4%),PFCS(93.8%)and six-layer PTED(92.3%).In addition,the vessel density in the PTED group was higher than the other groups on the 14th *** together,it is proved that the PTED,especially three-layer PTED,is more conducive to the fullthickness dermis-defect repair and the construction of the three-dimensional vascular networks,indicating its potential application in dermis-defect repair.

关键词： bone marrow mesenchymal stem cell sheet fibroblasts cell sheet endothelial cells pre-vascularized tissueengineered dermis dermis-defect repair

Optimal Initialization and Starting Approach of Synchronous Condenser Integrated Power Grid

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 248-260页

作者： Puyu Wang Xing liu Qingwen Mou Tao Yuan Tianming Gu Hemin Yang Xiao-Ping zhang zhengrong Xiang Chunyi Guo School of Automation Nanjing University of Science and TechnologyNanjing 210094China NARI Group Corporation/State Grid EPRI and also with NARI Technology Co.Ltd. Nanjing 211106China School of Engineering University of BirminghamBirminghamB152TTUnited Kingdom State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China

Synchronous condensers(SCs)are generally used at the receiving-end stations of ultra-high-voltage direct current(UHVDC)transmission systems due to their strong reactive power support and flexible regulation of reactive power according to the interconnected grids operating *** this paper,different starting control schemes of a SC integrated power grid are investigated providing four main contributions:1)The principle of reactive power support of the SC on the interconnected power grid is analytically studied,providing the establishment of mathematical models.2)Four different starting control schemes are developed for the initialization and SC integration,*** Scheme 1,a preset initial falling speed is directly utilized without initialization;in Scheme 2,a black start sequential control approach with a static frequency converter(SFC)is proposed;in Scheme 3,PI/PD/PID controllers are respectively applied for the excitation device at the speed-falling stage;in Scheme 4,a pre-insertion approach of an energy absorption component with R/L/RL is utilized to suppress the surges at the SC integration instant.3)The dynamic behaviors of four different starting schemes at specific operating stages are evaluated.4)The success rate of SC integration is analyzed to evaluate starting control *** of the SC interconnected system with four different starting control schemes is evaluated in the timedomain simulation environment PSCAD/EMTDC^(TM).The results prove the superiority of the proposed starting control approach in Scheme 4.

关键词： Black start dynamic behaviors excitation system pre-insertion of energy absorption components starting control schemes static frequency converter(SFC) success rate of integration synchronous condenser(SC)