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Adaptive Modulation with Channel Estimation in High-Speed Packet-Based OFDM Communication Systems

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The Journal of China Universities of Posts and Telecommunications 2004年第Z1期11卷 76-82页

作者： HOU Xiao-lin WU Jun-li yin chang-chuan yue guang-xin School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R.China School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R.China School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R.China School of Telecommunication Engineering Beijing University of Posts and Telecommunications Beijing 100876 P.R.China

In this paper, adaptive modulation with channel estimation in high-speed packet-based Orthogonal Frequency Division Multiplexing (OFDM) communication systems for beyond 3G are discussed. Different adaptive modulation and channel estimation methods are presented and compared, then those methods suitable for our intended application are chosen. Conclusions can be drawn from computer simulations that with proper selection of packet length and subband width, wide subband adaptive modulation with Least Square plus Discrete-time Fourier Transform (LS-DFT) channel estimation can give an acceptable performance with low complexity for channel with low Doppler shift and small path delay. Otherwise, narrow subband or subcarrier adaptive modulation together with LS-DFT plus Decision Directed (LS-DFT-DD) must be used.

关键词： OFDM adaptive modulation channel estimation beyond 3G

Facile fabrication of highly durable superhydrophobic strain sensors for subtle human motion detection

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Journal of Materials Science & Technology 2022年第15期110卷 35-42页

作者： li-chuan Jia chang-Ge Zhou Kun Dai Ding-xiang Yan Zhong-ming li College of Electrical Engineering Sichuan UniversityChengdu 610065China College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China College of Materials Science and Engineering The Key Laboratory of Material Processing and Mold of Ministry of EducationZhengzhou UniversityZhengzhou 450001China School of Aeronautics and Astronautics Sichuan UniversityChengdu 610065China

Endowing strain sensors with superhydrophobicity is of great importance to guarantee their long-term service under harsh environments(such as wet,acid,alkali and salt atmospheres),whereas,the development of superhydrophobic strain sensors remains a great ***,we realized a superhydrophobic and highly sensitive sensor for subtle human motion detection by designing a superhydrophobic and electrically conductive coating on cotton textile,via a facile drop-coating *** resultant strain sensor showed a large water contact angle of 161.3°and a low sliding angle of 3.8°The superhydrophobic characteristics can keep almost unchanged even after undergoing 1000 peeling cycles,1000 stretchingrelease cycles,and 1000 bending-releasing cycles,revealing its excellent mechanical *** sensitivity with the maximum gage factor of 169 was achieved for the strain sensor under a small strain of0–10%,and the sensing performance also showed well ***,our sensor can effectively detect various subtle human physiological signals and body motions even under harsh *** admirable features make the sensor promising applications in wearable electronics,personalized health monitoring,sound recognition,and so on.

关键词： Strain sensors Superhydrophobicity High sensitivity Drop coating Durable

Elimination of HBr from CH_3Br by Cu^+ and Au^+:A DFT study

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Chinese Chemical Letters 2008年第7期19卷 881-884页

作者： Tao Hong li chuan ming Wang xiang Yi liu Xiao guang Xie Faculty of Chemistry Southwest Forestry University Kunming 650224 China Department of Biology Honghe University Menzi 661100 China Department of Chemistry Yunnan University Kunming 650091 China

The elimination of HBr from CH3Br by ground state of Cu＋ and Au＋ has been investigated by using DFT methods. A mechanism of one-step HBr elimination leading to CuCH2＋ was identified. For the formation of AuCH2＋, besides the one-step mechanism, another two-step HBr elimination pathway through a C-Br bond insertion intermediate was also found, and this pathway is energetically more favorable than the one-step mechanism. The calculated reaction energy barriers show that the formation of AuCH2＋ is energetically much more favorable than the formation of CuCH2＋. The experimental observations are well explained.

关键词： Copper and gold Alkyl halide HBr elimination

Natural Variation of Leaf Thickness and Its Association to Yield Traits in indica Rice

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Journal of Integrative Agriculture 2014年第2期13卷 316-325页

作者： liU chuan-guang ZHOU xin-qiao CHEN Da-gang li li-jun li Ju-chang CHEN You-ding Rice Research Institute Guangdong Academy of Agricultural Sciences/Guangdong Key Laboratory of New Technology in Rice Breeding

Leaf thickness is an important morphological trait in rice. Its association to the yield potential, as of now has not been documented because of the shortage of the equipment which could conveniently measure the leaf thickness in rice. In this study, the thickness of top three leaves of 208 cultivars had been determined by a nondestructive rice leaf thickness instrument for the research of the natural variation of leaves thickness and its association to yield traits in indica rice. The results showed that the flag leaf was the thickest, and the 2nd leaf was thicker than the 3rd leaf. Analysis of variance indicated the existence of wide genetic diversity of leaf thickness among the investigated indica rice genotypes. The tight correlation among the thicknesses of the top three leaves means that the leaf thickness traits share one genetic control system. Leaf thickness had a significant positive correlation with leaf length and a positive correlation with leaf width, indicated that thicker leaf was beneficial to increasing the single leaf area. The results of correlation analysis revealed that thicker leaf should be profitable to the leaf erection, higher numbers of grains per panicle and higher grains weight per panicle. However, the significantly negative correlation between leaf thickness and number of panicles per plant counteracted the profitability from increased grains weight per panicle, so that the correlations of the thicknesses of the top three leaves to yield and biomass were positive but not significantly. It has made great progress in the genetic improvement of leaves thickness in inbred indica rice breeding in guangdong Province, China, since the 1990s.

关键词： indica rice leaf thickness variation yield

Synthesis of Ultraviolet Absorption Polylactide via Immortal Polymerization of rac-Lactide Initiated by a Salan-yttrium Catalyst

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Chinese Journal of Polymer Science 2018年第2期36卷 202-206页

作者： Wei Zhao chuan-Yang li Chun-Ji Wu xin-li liu Ze-Huai Mou chang-guang Yao Dong-Mei Cui State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Chinese Academy of Sciences Changchun BranchChangchun 130022China College of Bioresources Chemical and Materials Engineering Shaanxi University of Science and TechnologyXi'an 710021China

A highly efficient strategy for the synthesis of polylactide with the UV absorption ability was established by employing a Salan-yttrium complex（acting as a fast runing catalyst） combined with large excess hydroxyl functionalized benzophenone, BP′-OH. During polymerization, BP′-OH, acting as the chain transfer agent, attached to the active rare-earth metal catalyst via a rapid-reversible exchange reaction to initiate the polymerization. Thus, more polyester chains appeared to grow from one active metal species, and the UV absorption fragments were incorporated into the polymer chains at specific sites, in situ. A high productivity up to 1000 mol LA/mol（Salan-Y） was successfully achieved and 100 BP′-labeled PLA chains grew from each active metal center.

关键词： Yttrium catalyst Ring-opening polymerization Polylactide Ultraviolet absorption

A computational study on the gas phase reaction of Os^+ with N_2O

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Chinese Chemical Letters 2009年第8期20卷 1010-1014页

作者： Tao Hong li chuan ming Wang Shi Wen Yu xiang Yi liu Hui Fu Xiao guang Xie Faculty of Chemistry Southwest Forestry University Kunming 650224 China Department of Biology Honghe University Menzi 661100 PR China Department of Chemistryl Qujing Normal University Qujing 650011 China Department of Chemistry Yunnan University Kunming 650091 China

The reaction of Os^＋（^6D, ^4F） with N20 has been investigated at B3LYP/TZVP and CCSD（T）/6-311＋G^＊ levels of theory. The mechanisms corresponding to O-atom and N-atom transfer reactions have been revealed. It was found that on the sextet reaction surface both the O-atom and N-atom transfer reactions undergo through direct-abstraction mechanism, leading to the formation of OsO^＋ and OsN^＋, whereas on quartet surface the two reactions undergo through O-N bond or N-N bond insertion mechanism. The calculated energetics shows that the reactions on the sextet surface have notable energy barriers, whereas the reactions on quartet surface are barrierless. ？2009 Xiao guang Xie. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： O-Atom transfer N-Atom transfer Abstraction Insertion

Inhibition of Electrical Tree Initiation inside HighVoltage Cross-linked Polyethylene Cable with Nonlinear Shielding Layer

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Inhibition of Electrical Tree Initiation inside HighVoltage ...

Systems model-guided rice yield improvements based on genes controlling source, sink, and flow

第八届中国功能材料及其应用学术会议

作者： li chang-ming ZHANG guang-xiang li Chunyang HAN Bao-zhong Key Laboratory of Engineering Dielectrics and Its Application Ministry of EducationHarbin University of Science and Technology Deyang Products Quality Supervision & Inspection Instiute Far East Holding Group Co.Ltd.

ISBN: (纸本)9783037859698

Electrical tree aging is one of the leading factors causing degradation and breakdown of insulation performance of high-voltage cross-linked polyethylene(XLPE) cable.A lot of attention has been paid to inhibiting electric tree initiation and propagation inside high-voltage *** this study,insulation composites with nonlinear electrical conductivity are *** results show that these composites are helpful for enhancing the apparent breakdown electric field strength of XLPE in the pole electrode system.A kind of high-voltage XLPE insulated cable with new structure is designed by using these composites as nonlinear shielding *** simulation results indicate that nonlinear shielding layer can obviously improve the distribution of electrical field at the defect of insulation surface of high-voltage XLPE cable,and decrease the maximum electrical field strength at the *** new structure is potential for effectively inhibiting electrical tree initiation inside high-voltage XLPE insulation cable,thus increasing life span and operational reliability of the cable.

关键词： High-voltage cable Cross-linked polyethylene Nonlinear insulation material Electrical tree

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Journal of Integrative Plant Biology 2018年第12期60卷 1154-1180页

作者： Pan li Tiangen chang Shuoqi chang xiang Ouyang mingnan Qu Qingfeng Song Langtao Xiao Shitou Xia Qiyun Deng xin-guang Zhu State Key Laboratory of Hybrid Rice Key Laboratory of Phytochromes Hunan Agriculture University State Key Laboratory of Hybrid Rice Hunan Hybrid Rice Research Center National Key Laboratory for Plant Molecular Genetics CAS Center of Excellence of Molecular Plant Sciences Shanghai Institute of Plant Physiology and Ecology CAS

A large number of genes related to source, sink,and flow have been identified after decades of research in plant genetics. Unfortunately, these genes have not been effectively utilized in modern crop breeding. This perspective paper aims to examine the reasons behind such a phenomenon and propose a strategy to resolve this situation. Specifically, we first systematically survey the currently cloned genes related to source, sink, and flow;then we discuss three factors hindering effective application of these identified genes, which include the lack of effective methods to identify limiting or critical steps in a signaling network, the misplacement of emphasis on properties, at the leaf, instead of the whole canopy level,and the non-linear complex interaction between source,sink, and flow. Finally, we propose the development of systems models of source, sink and flow, together with a detailed simulation of interactions between them and their surrounding environments, to guide effective use of the identified elements in modern rice breeding. These systems models will contribute directly to the definition of crop ideotype and also identification of critical features and parameters that limit the yield potential in current cultivars.

关键词： Systems model-guided rice yield improvements based on genes controlling source

MdWRKY40is directly promotes anthocyanin accumulation and blocks MdMYB15L, the repressor of MdCBF2, which improves cold tolerance in apple

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Journal of Integrative Agriculture 2023年第6期22卷 1704-1719页

作者： XU Peng-yue XU li XU Hai-feng HE Xiao-wen HE Ping chang Yuan-sheng WANG Sen ZHENG Wen-yan WANG chuan-zeng CHEN xin li lin-guang WANG Hai-bo Shandong Institute of Pomology Shandong Academy of Agricultural SciencesTai’an 271000P.R.China Modern Agriculture Research Institute of Yellow River Delta Shandong Academy of Agricultural SciencesDongying 257000P.R.China

Cold stress is an important factor that limits apple production. In this study, we examined the tissue-cultured plantlets of apple rootstocks ‘M9T337' and ‘60-160', which are resistant and sensitive to cold stress, respectively. The enriched pathways of differentially expressed genes(DEGs) and physiological changes in ‘M9T337' and ‘60-160' plantlets were clearly different after cold stress(1°C) treatment for 48 h, suggesting that they have differential responses to cold stress. The differential expression of WRKY transcription factors in the two plantlets showed that MdWRKY40is and MdWRKY48 are potential regulators of cold tolerance. When we overexpressed MdWRKY40is and MdWRKY48in apple calli, the overexpression of MdWRKY48 had no significant effect on the callus, while MdWRKY40is overexpression promoted anthocyanin accumulation, increased callus cold tolerance, and promoted the expression of anthocyanin structural gene MdDFR and cold-signaling core gene MdCBF2. Yeast one-hybrid screening and electrophoretic mobility shift assays showed that MdWRKY40is could only bind to the MdDFR promoter. Yeast twohybrid screening and bimolecular fluorescence complementation showed that MdWRKY40is interacts with the CBF2inhibitor MdMYB15L through the leucine zipper(LZ). When the LZ of MdWRMY40is was knocked out, MdWRKY40is overexpression in the callus did not affect MdCBF2 expression or callus cold tolerance, indicating that MdWRKY40is acts in the cold signaling pathway by interacting with MdMYB15L. In summary, MdWRKY40is can directly bind to the MdDFR promoter in order to promote anthocyanin accumulation, and it can also interact with MdMYB15L to interfere with its inhibitory effect on MdCBF2, indirectly promoting MdCBF2 expression, and thereby improving cold *** results provide a new perspective for the cold-resistance mechanism of apple rootstocks and a molecular basis for the screening of cold-resistant rootstocks.

关键词： MdWRKY40is anthocyanin accumulation MdMYB15L MdCBF2 cold tolerance