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| 1 | A Low-Complexity PTS Based on Greedy and Genetic Algorithm for OFDM Systems显示文摘Partial transmit sequence(PTS) is one of effective technique to reduce high Peak-to-average power ratio(PAPR) in Orthogonal frequency division multiplexing(OFDM) system. However, the complexity of Original PTS(O-PTS) increases exponentially with the number of sub-blocks. To reduce the computational complexity while still offering a lower PAPR, a new PTS method is proposed to search for suboptimal rotating vectors in this paper. In the proposed method, the candidate rotation vectors are generated based on greedy and genetic algorithm.We also combine the proposed method and the superimposed training sequence method to get a further PAPR reduction. The theory and simulations results show that the proposed method can achieve better PAPR reduction and significantly reduce the computational complexity. | LUO Renze ZHANG Chengsen NIU Na LI Rui | 2015 | Chinese Journal of Electronics2015，24，4： | 10 |
| 2 | A Review on the Taxonomic,Evolutionary and Phytogeographic Studies of the Lotus Plant(Nelumbonaceae:Nelumbo)显示文摘Nelumbo Adans.(Nelumbonaceae) is an important member of the early-diverging eudicots.It contains two extant species:N.nucifera Gaertn.(the Sacred lotus),distributed in Asia and Australia and N.lutea Willd.(the American lotus),occurring in North America.This paper reviews the taxonomic,evolutionary and phytogeographic studies of the genus Nelumbo,and also raises scientific questions about it in further paleobotanic research.There are about 30 fossil species of Nelumbo established since the Early Cretaceous.Based on fossil studies,the ancestors of the extant N.nucifera and N.lutea are respectively considered to be N.protospeciosa from the Eocene to Miocene of Eurasia,and N.protolutea from the Eocene of North American.However,molecular systematic studies indicate that N.nucifera and N.lutea are probably split from a common ancestor during the Late Miocene to Early Pliocene,or even the Pleistocene,rather than separate relicts from extinct species on different continents.The characters of lotus stomatal development,seedling morphology as well as its flowering,pollination and fertilization in air reveal that it evolves from the land plants.Fossil data of Nelumbo indicates that the genus first occurs in mid-latitude area of Laurasia in the Early Cretaceous,then becomes widespread in North America and Eurasia and expands into Africa and South America during the Late Cretaceous; the genus probably colonizes the Indian Subcontinent from Asia during the Early Eocene after the collision of India and the Asian plates; the genus becomes extinct in Europe,but survives in Asia and North America during the Quaternary Ice Age,and later forms the present East Asia and North Australia-North America disjunctive distribution. | LI Ya Popova SVETLANA YAO Jianxin LI Chengsen | 2014 | Acta Geologica Sinica(English Edition)2014，88，4： | 7 |
| 3 | Characterization and origin of charcoalified foxtail millet(Setaria italica) from the Chenyuan Site of the Western Zhou Dynasty in Shangluo, SE Shaanxi, China显示文摘In this paper, we discuss charcoalified foxtail millet grains dated to the middle to late Western Zhou Dynasty and collected from the Chenyuan archeological site in Shangluo, in China's southeastern Shaanxi Province. We assigned these specimens to the species Setaria italica based on the following characteristics: an obtuse chalazal apex with missing stigmatic remains; an undulant seed surface composed of rectangular cells with undulate anticlinal walls; an elongated and deeply depressed embryo extending to almost the full seed length; and spherical starch grains. We suggest that the spread of foxtail millet from its original northern distribution center to the southern slopes of the Qinling Mountains could be attributed to: its prominence across Zhou crop systems; the latter area's arid or subarid climate; and the migration south of Zhou people fleeing severe conflict between their nation and northern nomads. | FENG GuangPing LU HuaYu ZHAO JianCheng YANG YaChang LI ChengSen ZHAO ZhiJun YUAN ShunQuan BAO Yan ZHONG Bei | 2013 | 科学通报2013，58，S1： | 2 |
| 4 | Early Miocene Mosses from Weichang, North China, and their Environmental Significance显示文摘Twenty-seven moss specimens collected from the Guangfayong section(Early Miocene,22.1Ma)of the Weichang District,North China were investigated in the present study.Based on the morphological and anatomical features of gametophytes,all specimens were found to belong to three species:Leptodictyum riparium,Drepanocladus subtrichophyllus sp.nov.,and Amblystegium varium,all of which belong to the family Amblystegiaceae.The microhabitats and living environments of fossil mosses were also investigated based on comparison with living mosses.The results suggest that these mosses grew primarily at the edges of rivers,streams,and lakes and favored being submerged in streams or lakes in the Weichang District in the Early Miocene. | GUO Caiqing YAO Jianxin WU Pengcheng LI Chengsen | 2013 | Acta Geologica Sinica(English Edition)2013，87，6： | 2 |
| 5 | Paleophytochemical Constituents from the Pliocene Fossil Wood of Pinus Armandii from Longling,Yunnan显示文摘摘要:保存的石块木头的标本在上新世棕色的煤木质化并且作为 Pinus armandii Francher 识别了来自一露天开采在在西方的云南省的 Longling 的 coalmine,中国。用液体列层析七孤立的石块木头的 Phytochemical 调查加重(17 ) 包括新 fluorene 衍生物命名 11,11-dimethyl-11H-benzo [b ] fluorene。一进一步, 28 volatiles 被煤气的层析团检测 spectrometry (GCMS ) ,分光镜的调查方法,包括的 MS 和 1D 和 2D-NMR 技术阐明了七混合物的结构。通常发生在的自然产品, isopimara 和芪的二种类型现存并且上新世石块 P。armandii 在沉积在某些情形下面在埋葬期间显示 phytochemical 忠实。能在上新世 P 禁止破坏木头的真菌的活动的芪的发现。armandii 推动假设 P 的这根上新世石块木头的化学保藏。在棕色的煤的 armandii 可能对破坏木头的真菌贡献内部自然禁止者的存在。 | ZHAO Youxing LI Chengsen YI Tiemei LUO Xiaodong ZHOU Jun | 2008 | Acta Geologica Sinica(English Edition)2008，82，6： | 2 |
| 6 | Pliocene charcoals from Shanxi Province of China and their application to studies of prehistoric wildfires显示文摘Charcoals collected from the middle-late Pliocene sediments of the Taigu Basin,Shanxi Province,China,have been identified as Ulmus sp.(Ulmaceae),Prunus sp.,Maloidoxylon sp.(Rosaceae),and Maclura sp.(Moraceae).These taxa,along with the previously known fossils,indicate the occurrence of temperate climate and local wildfire at that time.Charcoals of trees and/or shrubs and the morphological changes of these charcoals demonstrate that crown fires and surface fires occurred in the Taigu Basin during the middle-late Pliocene. | CHENG YeMing JIANG XiaoMei LI ChengSen WANG YuFei | 2011 | Science China Earth Sciences2011，54，4： | 1 |
| 7 | Studies on fossil Metasequoia from northeast China and their taxonomic implications 显示文摘 | Liu Yunju Li Chengsen Wang Yufei | 1999 | Botanical Journal of Linnean Society1999，130，： | 1 |
| 8 | New Fossil Liverworts from the Lower Cretaceous of Western Liaoning, China显示文摘Sixteen liverwort specimens collected from the Lower Cretaceous Yixian Formation of Huangbanjigou Village, Liaoning Province, China are studied in this work. The plants are thalloid and preserved in brown arenaceous mudstone as impressions. Based on examinations, the liverworts are assigned to two new genera and five new species: Riccardiothallus palmata sp. nov., Pallaviciniites stricta sp. nov., Pellites latithallus gen. et sp. nov., Conocephalumites hexagonites gen. et sp. nov. and Metzgerites multifidus sp. nov., belonging to five families and five genera. The fossil research indicates that the divergence of families, Aneuraceae and Metzgeriaceae, Pallaviciniaceae and Hymenophytaceae,Pelliaceae and Fossombroniaceae, was in the Lower Cretaceous(125 Ma). The research provides significant additions to the fossil liverwort records in Western Liaoning and offers fossil evidence for studying the classification and evolution of extant liverworts. | GUO Caiqing YAO Jianxin ZHANG Jianwei WU Pengcheng LI Chengsen | 2017 | Acta Geologica Sinica(English Edition)2017，91，5： | 1 |
| 9 | The stomatal apparatus of Lycopodium japonicum and its Drepanophycus spinaeformis 显示文摘 | Sun Tongxin Dlanne E Li Chengsen | 2005 | Botanical journal of the Linnean society2005，149，： | 1 |
| 10 | Pollen morphology in Saxifraga(Saxifragaceae) from Ny-Alesund, Svalbard, Arctic, and its taxonomic significance显示文摘Pollen morphology of eight species of Saxifraga,i.e.S.cespitosa,S.oppositifolia,S.cernua,S.nivalis,S.aizoides,S.rivularis,S.hieraciifolia,and S.hirculus,collected from Ny-Alesund,Svalbard,Arctic was examined using light and scanning electron microscopy.Pollen grains of Saxifraga species are subprolate or prolate,3-colpate,15.4–44.4μm in the polar axis,11.4–34.6μm in the equatorial axis,and show a P/E ratio 1.19–1.40.On the basis of exine ornamentation,four pollen types,viz.,the S.oppositifolia type(striate without scabrae on the muri),S.cernua type(striate with scabrae on the muri),S.nivalis type(microreticulate and operculum absent),and S.cespitosa type(microechinate and operculum present),were recognized.Hierarchical cluster analysis of the pollen morphological characters indicated that pollen morphology supports the infrageneric classification of the genus Saxifraga. | YAO Yifeng Bera Subir Ferguson David Kay LI Chengsen | 2014 | Advances in Polar Science2014，25，2： | 1 |
| 11 | Eucommia( Eucommiaceae ), a potential biothermometer for the reconstruction of paleoenvironments 显示文摘 | Wang Yufei Li Chengsen Margaret E Collinson | 2003 | American Journal of Botany2003，90，1： | 1 |
| 12 | Eucommia (E ), a potential biothermometer for the reconstruction of paleoenvironments 显示文摘 | Wang Yufei Li Chengsen Collinson M E | 2003 | American Joural of Botany2003，90，1： | 1 |
| 13 | High-frequency enhanced response based on Sb_(2)Te_(3)topological insulators显示文摘Topological insulators represent a new quantum phase of matter with spin-polarized surface states that are protected from backscattering, exhibiting electronic responses to light, such as topological quantum phase transitions. However, the effects of high-frequency driving topological intrinsic systems have remained largely unexplored challenges experimentally for high-sensitivity terahertz detection. In this study, by integrating Sb2Te3 topological insulators with subwavelength metal antennas through micro-nano processing, a high-frequency terahertz detector with high sensitivity is proposed. The enhanced response originates from the asymmetric scattering of the surface electrons in the Sb_(2)Te_(3) flakes induced by the terahertz wave. The device displays room-temperature photodetection with a responsivity of 192 mA/W and equivalent noise power of less than 0.35 nW/Hz^(1/2) in the frequency range from 0.02 to 0.3 THz. These results pave the way for the exploitation of topological insulators for high-frequency operation in real-time imaging within long-wavelength optoelectronics. | SHI ZHANG CHAOFAN SHI WEIWEI TANG LIBO ZHANG LI HAN CHENGSEN YANG ZHENGYANG ZHANG JIAN WANG MIAO CAI GUANHAI LI CHANGLONG LIU LIN WANG XIAOSHUANG CHEN WEI LU | 2022 | Photonics Research2022，10，10： | 1 |
| 14 | Natural traps of spores and pollen grains from the region surrounding Wenbi Reservoir, Yunnan, China显示文摘We did a comparative analysis of pollen and spores from five kinds of natural pollen traps at Wenbi Reservoir, northwest Yunnan, China. The natural traps were the surface soil, ground inhabiting mosses, spider webs, tree bark and moss/lichen on trees. These traps showed qualitative and quantitative variations in the pollen and spore spectra. The palynomorphs recovered from the soil samples of trees and shrubs ranged from 90.54% to 95.98% of the total counts. These counts were higher than counts from ground mosses(53.13%–81.66%), spider webs(61.71%), bark samples(53.8%) and moss/lichen on trees(50%–53.6%). The result of pollen/spore analysis showed that surface soil, ground mosses and spider webs better reflect the local vegetation compared with tree bark or moss/lichen on trees. | SONG XiaoYan BERA Subir YAO YiFeng BLACKMORE Stephen LI ChengSen | 2013 | 科学通报2013，58，S1： | 1 |
| 15 | Stomatal apparatus of Lycopodium japonicum and its bearing on the stomata of devonian lycophyte Drepanophycus spinaeformis显示文摘 | Sun Tongxing Dianne Edwards Li Chengsen | 2005 | Botanical Journal of the Linnean Society2005，149，2： | 1 |
| 16 | A new glecheniaceous fern Chansitheca (Sphenopteris) wndaensis from the Lower Permian of Wuda, Nei Mongol, China 显示文摘 | Deng Shenghul Sun Keqin Li Chengsen | 2000 | Acta Botanica Sinica2000，42，5： | 1 |
| 17 | The stomatal appara- tus of Lycopodiumjaponicum and its bearing on the stomata Devonian lycophyte Drepanophycus spinaeformis 显示文摘 | Sun Ton~in Dlanne E Li Chengsen | 2005 | Bo- tanical journal of the Linnean Society2005，149，2： | 1 |
| 18 | Pliocene taxodiaceous fossil wood from southwestern Ukraine and its palaeoenvironmental implications显示文摘Mineralized wood collected from Late Pliocene strata near Gorbki village in the Transcarpathian region of Beregovo Kholmogor'e in southwestern Ukraine was anatomically studied and identified.The wood possesses distinctive anatomical features and has distinct growth rings with an abrupt transition from early-to late-wood.Wood consists of tracheids with 1-3 seriate,dominating bi-seriate,opposite pits on the radial walls and taxodioid crossfield pitting,indentures present.Rays are uni-seriate and 1 to 73 cells high.Ray parenchyma horizontal walls thin and smooth.Axial parenchyma distributed in early-and late-wood and is solitary and diffuse,with end walls nearly smooth or slightly nodular.The combination of features observed in the wood indicates it belongs to the conifer family Taxodiaceae and is most similar to modern Sequoia and assigned to the fossil genus Sequoioxylon.Comparison with species of Sequoioxylon show it is most similar to Sequoioxylon burejense,but ray tracheids were not found in our specimens.We describe the specimens here as Sequoioxylon cf.s.burejense noting this similarity.Extant Sequoia is distributed in the northern California coastal forest eco-region of northern California and southern Oregon in the United States where they usually grow in a unique environment with heavy seasonal precipitation(2500 mm annually),cool coastal air and fog drip.This study supplies magafossil evidence of Sequoioxylon as an element of the Late Pliocene forest community in Ukraine and indicates a climate with heavy seasonal precipitation and fog drip. | Yi Tiemei Li Chengsen Svetlana Syabryaj | 2013 | Journal of Palaeogeography2013，2，4： | 0 |
| 19 | A network for long-term monitoring of vegetation in the area of Fildes Peninsula, King George Island显示文摘Climate warming has become evident in the maritime Antarctic over the past decades, and has already influenced the growing season and the population size of two native vascular plants in Antarctica, Deschampsia antarctica and Colobanthus quitensis. Both vascular plant species are therefore regarded as good bioindicators of regional warming in west Antarctica. To carry out long-term monitoring of vegetation(mainly using D. antarctica) and build a comprehensive research platform for multi-disciplinary study(including botany, microbiology, ecology, and environmental science) for Chinese scientists, 13 permanent plots were established in January and February of 2013–2015 in the area of Fildes Peninsula(King George Island). Here we present the benchmark data of the first observations from these plots, including site characteristics, and the population and associates of D. antarctica in each plot. The basic data are important to understand the vegetation change, distribution range, and expansion of D. antarctica in Antarctica under future climate change scenarios. | YAO Yifeng WANG Xia LI Jinfeng YANG Jian CAO Shunan PENG Fang KURBATOVA Ljuba PETER Hans-Ulrich BRAUN Christina LI Chengsen | 2017 | Advances in Polar Science2017，28，1： | 0 |
| 20 | New plants of Gnetales from Early Cretaceous of China, and its bearing on the early evolution of Ephedraceae and Welwitschiaceae in Gnetales显示文摘The Gnetales are a higher group of Gymnosperms, but our current knowledge of the morphology of the early Gnetales is lacking. Most known specimens are fragmentary, which makes it difficult to elucidate the geological history and the early diversity and evolution of the group. New well-preserved specimens have been discovered in Liaoning, north China, and a detailed morphological study was carried out. The material belongs to three new genera: Spinobractea lanceoleta gen. et sp. nov., Latibractea divisa gen. et sp. nov. and Constrobilus ovata gen. et sp. nov. The record of the Ephedraceae can be traced back to the Jurassic. The Ephedraceae were quite successful in the Cretaceous, and the plant types and the environment that they inhabited shown that the Cretaceous plants were much more varied than their living relatives. However, some types became extinct, and some features were lost. The record of the Welwitschiaceae can be traced back to the Triassic. Features of the leaf venation and the seeds are the primary features used for recognition of this family in both living and fossil plants. These features are so conservative that they have shown almost no major changes since the Triassic. | LIU HaiMing FERGUSON David K. LI ChengSen WANG YuFei | 2013 | 科学通报2013，58，S1： | 0 |
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