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Rapid Phase Ambiguity Elimination Methods for DOA Estimator via Hybrid Massive MIMO Receive Array

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Chinese Journal of Electronics 2024年第1期33卷 175-184页

作者： Xichao ZHAN Zhongwen sUN Feng sHU Yiwen CHEN Xin CHENG Yuanyuan WU Qi ZHANG Yifan LI Peng ZHANG school of Information and Communication Engineering Hainan University school of Electronic and Optical Engineering Nanjing University of Science and Technology

For a sub-connected hybrid multiple-input multiple-output(MIMO) receiver with K subarrays and N antennas, there exists a challenging problem of how to rapidly remove phase ambiguity in only single time-slot. A direction of arrival(DOA) estimator of maximizing received power(Max-RP) is proposed to find the maximum value of K-subarray output powers, where each subarray is in charge of one sector, and the center angle of the sector corresponding to the maximum output is the estimated true DOA. To make an enhancement on precision, Max-RP plus quadratic interpolation(Max-RP-QI) method is designed. In the proposed Max-RP-QI, a quadratic interpolation scheme is adopted to interpolate the three DOA values corresponding to the largest three receive powers of *** achieve the Cramer Rao lower bound, a Root-MUsIC plus Max-RP-QI scheme is developed. simulation results show that the proposed three methods eliminate the phase ambiguity during one time-slot and also show low computational complexities. The proposed Root-MUsIC plus Max-RP-QI scheme can reach the Cramer Rao lower bound,and the proposed Max-RP and Max-RP-QI are still some performance losses 2–4 d B compared to the Cramer Rao lower bound.

关键词： Phased arrays Interpolation Wireless sensor networks Direction-of-arrival estimation simulation Receiving antennas Massive MIMO

Template-directed synthesis of Three Metal Oxalates via 4-Connected Building Units

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Chemical research in Chinese Universities 2014年第6期30卷 889-893页

作者： TIAN Ruijing WANG Fuxiang DU Chunyu FENG Lijuan LIU Ying ZHANG Cailing PAN Qinhe Key study Center of the National Ministry of Education for Tropical Resources Utilization Department of Materials and Chemical Engineering Hainan University Haikou 570228 P. R. China state Key Laboratory of Inorganic synthesis and Preparative Chemistry Jilin University Changehun 130012 P. R. China

Three novel compounds, [Co（en）3]2[Zr2（C2O4）7]·2H20（HNU-2, en=ethylenediamine）, [Co（NH3）6]· [Ce（CzO4）3（H2O）]·H2O（HNU-3） and [Co（dien）2][Gd（C2On）3]·0.75H2O（HNU-4, dien=dethylenetriamine） were hydro- thermal synthesized based on the templates of [Co（en）3]C13, [C0（NH3）6]C13 and [Co（dien）2]C13, respectively. The Zr4＋ Ce3＋ and Gd3＋ cations are all coordinated by four oxalates to form [M（C2O4）n（H2O）n]m （M=Zr, Ce or Gd; n=0 or 1; m=4 or 5）, which are similar to [In（C2O4）4]5- in NKB-1, and can be regarded as 4-connected building units. The [M（C2O4）a（H2O）n]m units are connected via sharing the bis-bidentate bridging oxalate ligands to form binuclears in HNU-2 and 1D ＂zigzag＂ chains in HNU-3 and HNU-4. cular building units to design 3D open frameworks with It is suggested that these compounds could be used as mole- zeolite topologies.

关键词： Coordination polymer Template-directed synthesis Metal oxalate

The modification effects of roselle anthocyanin film on shrimp texture via water distribution controlling and protein conformation maintenance

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Food Bioscience 2022年第5期49卷 872-883页

作者： Jiayin Huang Zhiheng Hu Lingping Hu Gaoshang Li Chunhong Yuan Jianchu Chen Yaqin Hu Institute of Food Engineering College of Biosystems Engineering and Food ScienceZhejiang UniversityHangzhouZhejiang310058China College of Food science and Engineering Hainan Tropical Ocean UniversitySanyaHainan572022China Yazhou Bay Innovation Institute SanyaHainan572022China d Marine Food Engineering Technology Research Center of Hainan ProvinceSanyaHainan572022China Collaborative Innovation Center of Marine Food Deep Processing SanyaHainan572022China hainan Key Laboratory of Herpetological research College of Fisheries and Life ScienceHainan Tropical Ocean UniversitySanyaHainan572022China Department of Food Production and Environmental Management Faculty of AgricultureIwate UniversityUeda4-3-5Morikoa020-8551Japan

The food’s perishable properties and people’s eco-friendly requirements have driven the biodegradable active packaging *** this study,modification behaviors of polyviniyl alcohol/hydroxypropyl methylcellulose/roselle anthocyanin-based(PHR)film on textural profiles of Penaeus vannamei were *** samples were packaged by PHR film with different roselle anthocyanin contents and stored at 4±1℃.The results indicated that PHR groups exhibited better texture with higher values of hardness(435.56±75.52 g),springiness(0.53±0.04 mm),chewiness(198.83±40.98 N)and resilience(0.45±0.04).The PHR film exerted positive influences on water migration by reducing drip loss and promoting conversion of free water into immobilized ***,the PHR film retarded protein denaturation via increasing myofibrillar protein and sulfhydryl group contents,decreasing TCA(trichloroacetic acid)-soluble peptide contents and maintaining protein secondary structure(higherα-helix ratio and lowerβ-sheet ratio).In conclusion,the PHR film improved shrimp texture by rearrangement of water distribution and stabilization of protein ***,the PHR film was a novel potential active packaging for shrimp texture enhancement.

关键词： Active packaging Textural properties Water migration Protein conformation

New explicit multi-symplectic scheme for nonlinear wave equation

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Applied Mathematics and Mechanics(English Edition) 2014年第3期35卷 369-380页

作者：李昊辰孙建强秦孟兆 Department of Mathematics College of Information Science and TechnologyHainan University state Key Laboratory of scientific and Engineering Computing Academy of Mathematics and System SciencesChinese Academy of Sciences

Based on splitting multi-symplectic structures, a new multi-symplectic scheme is proposed and applied to a nonlinear wave equation. The explicit multi-symplectic scheme of the nonlinear wave equation is obtained, and the corresponding multi-symplectic conservation property is proved. The backward error analysis shows that the explicit multi-symplectic scheme has good accuracy. The sine-Gordon equation and the Klein-Gordon equation are simulated by an explicit multi-symplectic scheme. The numerical results show that the new explicit multi-symplectic scheme can well simulate the solitary wave behaviors of the nonlinear wave equation and approximately preserve the relative energy error of the equation.

关键词： nonlinear wave equation multi-symplectic method backward error analysis

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A Multi-Watermarking Algorithm for Medical Images Using Inception V3 and DCT

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Computers, Materials & Continua 2023年第1期74卷 1279-1302页

作者： Yu Fan Jingbing Li Uzair Aslam Bhatti Chunyan shao Cheng Gong Jieren Cheng Yenwei Chen school of Information and Communication Engineering Hainan UniversityHaikou570100China state Key Laboratory of Marine Resource Utilization in the south China sea Hainan UniversityHaikou570100China school of Computer science and Technology Hainan UniversityHaikou570100China Graduate school of Information science and Engineering Ritsumeikan UniversityKyoto5258577Japan hainan Blockchain Technology Engineering research Center Hainan UniversityHaikou570100China TJ-YZ school of Network science Haikou University of EconomicsHaikou571127China

Medical images are a critical component of the diagnostic process for *** the quality of medical photographs is essential to the accuracy of a physician’s diagnosis,they must be encrypted due to the characteristics of digital storage and information leakage associated with medical *** watermark embedding algorithm embeds the watermark information into the medical image,which reduces the quality of the medical image and affects the physicians’judgment of patient *** addition,watermarks in this method have weak robustness under high-intensity geometric attacks when the medical image is attacked and the watermarks are *** paper proposes a novel watermarking algorithm using the convolutional neural networks(CNN)Inception V3 and the discrete cosine transform(DCT)to address above mentioned ***,the medical image is input into the Inception V3 network,which has been structured by adjusting parameters,such as the size of the convolution kernels and the typical architecture of the convolution ***,the coefficients extracted from the fully connected layer of the network are transformed by DCT to obtain the feature vector of the medical *** last,the watermarks are encrypted using the logistic map system and hash function,and the keys are stored by a third *** encrypted watermarks and the original image features are performed logical operations to realize the embedding of *** the experimental section,multiple watermarking schemes using three different types of watermarks were implemented to verify the effectiveness of the three proposed *** NC values for all the images are more than 90%accurate which shows the robustness of the *** experimental results demonstrate the robustness under both conventional and high-intensity geometric attacks of the proposed algorithm.

关键词： Inception V3 multi-watermarking DCT watermark encryption robustness

Integrated analysis reveals an association between the rhizosphere microbiome and root rot of arecanut palm

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Pedosphere 2021年第5期31卷 725-735页

作者： Hong LI Xiang MA Yanqiong TANG Chengliang YAN Xinwen HU Xi HUANG Min LIN Zhu LIU Key Laboratory of Tropical Biological Resources of Ministry of Education School of Life and Pharmaceutical SciencesHainan UniversityHaikou 570228(China) Biotechnology research Institute Chinese Academy of Agricultural SciencesBeijing 100081(China)

The rhizosphere microbial community is crucial to plant *** studies have explored the association between the rhizosphere microbiome and plant ***,few studies have focused on root rot in arecanut palm,a disease causing devastating effects and thus resulting in economic losses that considerably affect the development of the arecanut ***,rhizosphere samples were collected from both healthy arecanut palm plants and root-rotted arecanut palm plants,and the microbial communities were analyzed using high-throughput *** root-rotted samples exhibited distinct microbial community richness,diversity,and composition compared with the healthy samples,which was associated with p H according to the Mantel *** potential plant pathogens,including Proteobacteria,Bacteroidetes,Chytridiomycota,and Mortierellomycota,were significantly enriched in the root-rotted *** contrast,potentially beneficial plant microbes,such as Acidobacteria and Gemmatimonadetes,were significantly depleted in the root-rotted ***-occurrence networks were constructed to further identify microbial relationships in the root-rotted *** findings revealed ecological imbalance among beneficial bacteria in the root-rotted *** present study therefore provides an integrated view of the association between the microbial community and root rot in arecanut palm.

关键词： microbial community co-occurrence network ecological imbalance soil physicochemical characteristics high-throughput sequencing

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MDR:an integrative DNA N6-methyladenine and N4-methylcytosine modification database for Rosaceae

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Horticulture research 2019年第1期6卷 774-780页

作者： Zhao-Yu Liu Jian-Feng Xing Wei Chen Mei-Wei Luan Rui Xie Jing Huang shang-Qian Xie Chuan-Le Xiao hainan Key Laboratory for Biology of Tropical Ornamental Plant Germplasm Institute of Tropical Agriculture and ForestryHainan University570228 HaikouChina state Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen University510060 GuangzhouChina Inner Mongolia Academy of Agricultural and Animal Husbandry sciences 010031 HuhhotChina Department of Agronomy College of AgriculturePurdue UniversityWest LafayetteIN 47907USA

Eukaryotic DNA methylation has been receiving increasing attention for its crucial epigenetic regulatory *** recently developed single-molecule real-time(sMRT)sequencing technology provides an efficient way to detect DNA N6-methyladenine(6mA)and N4-methylcytosine(4mC)modifications at a single-nucleotide *** family Rosaceae contains horticultural plants with a wide range of economic ***,little is currently known regarding the genome-wide distribution patterns and functions of 6mA and 4mC modifications in the *** this study,we present an integrated DNA 6mA and 4mC modification database for the Rosaceae(MDR,http://***).MDR,the first repository for displaying and storing DNA 6mA and 4mC methylomes from sMRT sequencing data sets for Rosaceae,includes meta and statistical information,methylation densities,Gene Ontology enrichment analyses,and genome search and browse for methylated sites in *** provides important information regarding DNA 6mA and 4mC methylation and may help users better understand epigenetic modifications in the family Rosaceae.

关键词： database adenine modification

sulfate-assisted Ni/Fe-based electrodes for anion exchange membrane saline splitting

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Nano research 2024年第7期17卷 5985-5995页

作者： Yujun Han Li shao Yuhang Liu Guodong Li Tongzhou Wang Xuerong Zheng Jihong Li Xiaopeng Han Wenbin Hu Yida Deng school of Materials science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin UniversityTianjin 300072China state Key Laboratory of Marine Resource Utilization in south China sea School of Materials Science and EngineeringHainan UniversityHaikou 570228China state Key Laboratory of Inorganic synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

saline water electrolysis is an appealing strategy for hydrogen production,attracting more attention in recent ***-based electrodes exhibit promise as catalysts for saline water ***,they suffer from the inferior service life of the oxygen evolution reaction(OER).Herein,we report an oxygen-evolution electrode consisting of a sulfate-modulated nickel-iron hydroxide(NiFeOOH)affording as the catalytic active layer and Fe-Ni_(3)s_(2) as the corrosion-proof *** developed electrode only requires overpotentials of 220 and 292 mV to deliver the current density of 10 and 500 mA·cm^(−2),*** importantly,it presents long-term stability exceeding 140 and 100 h in 1 M KOH at high current densities of 500 and 1000 mA·cm^(−2),respectively,as well as 120 h for saline water electrolysis at 100 mA·cm^(−2).Experimental results reveal that the generated sulfate plays an indispensable role in improving stability and corrosion *** assembled and tested an anion exchange membrane electrolyzer with Pt/C and NiFes/NIF as the cathode and anode,respectively,under industrial *** overall water-splitting electrolyzer achieves an impressive energy conversion efficiency of 75%±0.5%.This report offers fresh insights into the design of stable NiFe-based electrodes,which may further promote its practical applications for saline water electrolysis.

关键词： saline water electrolysis oxygen evolution reaction anode material water splitting

Reinforcement of natural rubber latex with silica modified by cerium oxide:preparation and properties

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Journal of Rare Earths 2016年第2期34卷 221-226页

作者：张福全廖禄生王永周汪月琼黄红海李普旺彭政曾日中 Chinese Agricultural Ministry Key Laboratory of Tropical Crop Product Processing Agricultural Product Processing Research InstituteChinese Academy of Tropical Agricultural SciencesZhanjiang 524001China Agriculture Ministry Key Laboratory of Biology and Genetic Resources of Rubber TreeRubber Research InstituteChinese Academy of Tropical Agricultural SciencesDanzhou 571731China

Variable masses of nano cerium oxide (CeO2) were added into nano silica (siO2) to prepare the well-dispersed siO2-CeO2 suspension (siO2-CeO2), cetyltrimethyl ammonium bromide (CTAB) was used to adjust the compatibility of siO2-CeO2 with rubber matrix, then siO2-CeO2 modified by CTAB and curing formulas were mixed with fresh natural rubber (NR) latex to prepare NR/siO2-CeO2 nanocomposites that contained 0–10 parts of CeO2 by a new emulsion compounding method. The morphologies, cure characteristics, mechanical properties and thermal-oxidative stability of NR/siO2-CeO2 nanocomposites were investigated. The re-sults revealed that the presence of CeO2 in NR/siO2-CeO2nanocomposites was favorable for enhancing the interaction between NR matrix and fillers, helped to get smaller siO2-CeO2 particles with narrower particle size distribution, further improved the crosslink densities and mechanical properties of NR/siO2-CeO2 nanocomposites vulcanizates. Meanwhile, the addition of CeO2 increased the active energy at least 4.66%, obviously improved the thermal-oxidative aging-inhibiting properties of NR/siO2-CeO2 nanocomposites. Additionally, nanocomposites containing CeO2 promotedTg shift to high temperature direction, causing the nanocomposites featured higher tanδ at 0 oC and lower tanδ at 60 oC and exhibited comparable wet grip and lower rolling resistance when NR/siO2-CeO2nano-composites were used in tire tread compound.

关键词： cerium oxide silica natural rubber latex emulsion compound reinforcement aging-inhibiting property glass transition temperature rare earths

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