123,490 research outputs found
Conocephalus (Conocephalus) sulcifrontis Xia et Liu 1992
No full textConocephalus (Conocephalus) sulcifrontis Xia et Liu, 1992 (Figs. G) Conocephalus sulcifrontis Xia et Liu, 1992: 163 Distribution: China (Shanghai, Jiangsu).Published as part of Zhou, Min, Bi, Wen-Xuan & Liu, Xia-Wei, 2010, The genus Conocephalus (Orthoptera, Tettigonioidea) in China, pp. 49-60 in Zootaxa 2527 on page 52, DOI: 10.5281/zenodo.19645
Skyrmion-skyrmion and skyrmion-edge repulsions in skyrmion-based racetrack memory
No full textMagnetic skyrmions are promising for building next-generation magnetic memories and spintronic devices due to their stability, small size and the extremely low currents needed to move them. In particular, skyrmion-based racetrack memory is attractive for information technology, where skyrmions are used to store information as data bits instead of traditional domain walls. Here we numerically demonstrate the impacts of skyrmion-skyrmion and skyrmion-edge repulsions on the feasibility of skyrmion-based racetrack memory. The reliable and practicable spacing between consecutive skyrmionic bits on the racetrack as well as the ability to adjust it are investigated. Clogging of skyrmionic bits is found at the end of the racetrack, leading to the reduction of skyrmion size. Further, we demonstrate an effective and simple method to avoid the clogging of skyrmionic bits, which ensures the elimination of skyrmionic bits beyond the reading element. Our results give guidance for the design and development of future skyrmion-based racetrack memory
Phlogacanthus yangtsekiangensis C. Xia & Y. F. Deng, comb. nov.
No full textPhlogacanthus yangtsekiangensis (H. Lév.) C. Xia & Y. F. Deng, comb. nov. Basionym: Strobilanthes yangtsekiangensis Léveillé (1915: 7).⎯ Cystacanthus yangtsekiangensis (H. Lév.) Rehder (1935: 315). Type:⎯ CHINA. Yunnan: Dêqên Xian, Rives du fleuve Bleu à Ta-Tchai, 400–450 m, May–June 1912, E. E. Maire s.n. (holotype E!) Cystacanthus affinis Smith (1916: 103), syn. nov. Type: ⎯ CHINA. Yunnan: Lijiang Shi, Fengkow Valley, Lat. 27°40’N ”, 8000 ft., June 1914, G. Forrest 12493 (holotype E!; isotype A!, K!). Cystacanthus yunnanensis Smith (1916: 104), syn. nov. Type:⎯ CHINA. Yunnan: Dengchuan Xian, Tengchwan Valley, Lat. 26°5’N, 7000 ft, May 1913, G. Forrest 10007 (holotype E!). Distribution:— Phlogacanthus yangtsekiangensis is endemic to China and occurs in Sichuan and Yunnan. Ecology:—This species grows in thickets in the valley at the elevation of 400–2200 m. Conservation status:— Phlogacanthus yangtsekiangensis was collected from more than thirty localities and has a large area of occurrence in Jinsha Jiang Valley in N Yunnan and SW Sichuan Provinces which cover more than 20000 km 2. It is thus considered to be of Least Concern (LC) according to the IUCN (2001, 2011) Red List criteria and categories.Published as part of Xia, Chun & Deng, Yunfei, 2013, Phlogacanthus yangtsekiangensis, a new combination in Chinese Acanthaceae, pp. 58-60 in Phytotaxa 104 (1) on pages 58-59, DOI: 10.11646/phytotaxa.104.1.9, http://zenodo.org/record/477660
Recommended from our members
The system identification and control of Hammerstein system using non-uniform rational B-spline neural network and particle swarm optimization
Get PDFIn this paper a new system identification algorithm is introduced for Hammerstein systems based on observational input/output data. The nonlinear static function in the Hammerstein system is modelled using a non-uniform rational B-spline (NURB) neural network. The proposed system identification algorithm for this NURB network based Hammerstein system consists of two successive stages. First the shaping parameters in NURB network are estimated using a particle swarm optimization (PSO) procedure. Then the remaining parameters are estimated by the method of the singular value decomposition (SVD). Numerical examples including a model based controller are utilized to demonstrate the efficacy of the proposed approach. The controller consists of computing the inverse of the nonlinear static function approximated by NURB network, followed by a linear pole assignment controller
Phlugiolopsis tuberculata Xia & Liu 1993
No full text4. Phlugiolopsis tuberculata Xia & Liu, 1993 (Map. 1, Figs. 4, 12: G–H) Phlugiolopsis tuberculata Xia & Liu, 1993: 110; Liu & Jin, 1994: 109; Jin & Xia, 1994: 26; Shi & Ou, 2005: 359; Shi & Chang, 2005 a: 105; Shi & Chang, 2005 b: 122. Type specimen: male; type locality: Qianlingshan, Guiyang, Guizhou, China; location of type: Shanghai Entomological Museum of the Chinese Academy of Sciences. Material examined. 2 males and 2 females, Chishui, Guizhou, 28 Semptember 2000, collected by Fu-Ming Shi; 2 males and 1 female, Chishui, Guizhou, 6 October 2011, collected by Le-Hong Zhao and Guang-Lin Xie. Other specimens (conserved in alcohol): 1 male and 6 females, Chishui, Guizhou, collected by Le-Hong Zhao and Guang-Lin Xie. Distribution. China (Guangxi, Guizhou, Hunan).Published as part of Bian, Xun, Shi, Fu-Ming & Chang, Yan-Lin, 2012, Review of the genus Phlugiolopsis Zeuner, 1940 (Orthoptera: Tettigoniidae: Meconematinae) from China, pp. 1-21 in Zootaxa 3281 on page 8, DOI: 10.5281/zenodo.20992
Electronic structure and g factors of CdTe quantum ellipsoids
No full textThe electronic structure, electron and hole g factors and optical properties of CdTe quantum ellipsoids are investigated, in the framework of eight-band effective-mass approximation. It is found that the light-hole states come down in comparison with the heavy-hole states when the spheres are elongated, and become the lowest states of valence band. When the aspect ratio of the ellipsoid length to diameter (e) changes from smaller than 1 to larger than 1, the linear polarization factors change from negative to positive. The electron g factors of CdTe spheres decrease with increasing radius, and are nearly 2 when the radius is very small. Actually, as some of the three dimensions increase, the electron g factors decrease. More dimensions increase, the g factors decrease. more. The dimensions perpendicular to the direction of the magnetic field affect the g factors more than the other dimension. The light-hole and heavy-hole g factors of quantum spheres are equal, and change from 0.88 to -1.14 with increasing radius. When e 1) the light-hole g factor is smaller (larger) than the heavy-hole g factor. (c) 2006 Elsevier B.V. All rights reserved
Fig 1. – Dendrocalamus velutinus N.-H. Xia, V. T. Nguyen & V. D in Dendrocalamus velutinus N.-H. Xia, V. T. Nguyen & V. D. Vu (Poaceae), a new species from Vietnam
No full textFig 1. – Dendrocalamus velutinus N.-H. Xia, V. T. Nguyen & V. D. Vu. A. Culm and dormant bud; B. Culm sheath (abaxial view); C. Culm sheath (adaxial view); D. Leaf; E. Leaf ligule; F. Flowering branch; G. Pseudospikelet; H. Prophyll; I. Glume; J. Lemma; K. Palea; L. Pistil; M. Anther. [A-C: V. T. Nguyen NVT224, FSIV; D-M: V. T. Nguyen NVT260, FSIV] [Drawn by V. T. Nguyen]Published as part of Nguyen, Van Tho, Le, Viet Lam, Vu, Van Dung & Xia, Nian-He, 2012, Dendrocalamus velutinus N.-H. Xia, V. T. Nguyen & V. D. Vu (Poaceae), a new species from Vietnam, pp. 255-259 in Candollea 67 (2) on page 257, DOI: 10.15553/c2012v672a6, http://zenodo.org/record/571021
Millimeter-Wave UAV Coverage in Urban Environments
No full textComunicació presentada a 2021 IEEE Global Communications Conference (GLOBECOM), celebrat del 7 a l'11 de desembre de 2021 a Madrid, Espanya.With growing interest in mmWave connectivity for unmanned aerial vehicles (UAVs), a basic question is whether networks intended for terrestrial service can provide sufficient aerial coverage as well. To assess this possibility in the context of urban environments, extensive system-level simulations are conducted using a generative channel model recently proposed by the authors. It is found that standard downtilted base stations at street level, deployed with typical microcellular densities, can indeed provide satisfactory UAV coverage. Interestingly, this coverage is made possible by a conjunction of antenna sidelobes and strong reflections. As the deployments become sparser, the coverage is only guaranteed at progressively higher UAV altitudes. The incorporation of base stations dedicated to UAV communication, rooftop-mounted and uptilted, would strengthen the coverage provided their density is comparable to that of the standard deployment, and would be instrumental for sparse deployments of the latter.S. Rangan, W. Xia, S. Kang, and M. Mezzavilla were supported by NSF grants 1302336, 1564142, 1547332, and 1824434, NIST, SRC, and the industrial affiliates of NYU WIRELESS. A. Lozano and G. Geraci were supported by ERC grant 694974, by MINECO’s Project RTI2018-101040, by the Junior Leader Fellowship Program from “la Caixa" Banking Foundation, and by the ICREA Academia program. The work of V. Semkin was supported by the Academy of Finland
Optical properties and g factors of GaAs quantum rods
No full textThe Hamiltonian of the zinc-blende quantum rods in the framework of eight-band effective-mass approximation in the presence of external homogeneous magnetic field is given. The electronic structure, optical properties and electron g factors of GaAs quantum rods are investigated. We found that the electron g factors are very sensitively dependent on the dimensions of the quantum rods. As some of the three dimensions increase, the electron g factors decrease. The more the dimensions increase, the more the electron g factors decrease. The dimensions perpendicular to the direction of the magnetic field affect the electron g factors more than the other dimension. (c) 2006 Elsevier B.V. All rights reserved
Ellipsoidisporodochium S. B. Liu, J. W. Xia & X. G. Zhang 2022, gen. nov.
No full textEllipsoidisporodochium S.B. Liu, J.W. Xia & X.G. Zhang, gen. nov. MycoBank: 842196 Type species. Ellipsoidisporodochium photiniae S.B. Liu, J.W. Xia & X.G. Zhang Etymology. Composed of “ellipsoidisporo-” (ellipsoid spores) and “-dochium” (referring to the conidioma, i.e., sporodochium). Description. Asexual morph: mycelium consisting of septate, smooth and hyaline hyphae, thin-walled. Conidiomata sporodochial, appeared within 14 days or longer, formed on the agar surface, globose to subglobose, pale bluish-green in the center, with a layer of transparent conidia on the outside. Sporodochial conidiophores irregularly branched, tapering towards apex, swelling at base; sporodochial phialides monophialidic, fusoid to ampulliform, smooth, thin-walled. Conidia solitary, obovoid to ellipsoid, hyaline to subhyaline, guttulate, smooth, apex obtuse, base with inconspicuous to conspicuous hilum. Sexual morph: not observed. Notes. In the phylogenetic trees (Fig 1), Ellipsoidisporodochium is allied to Paratubakia and Oblongisporothyrium (BYPP = 1 and ML-BS = 98%) with well support, and forms a separate lineage with full support (BYPP = 1 and ML-BS = 100%), suggesting a genus of its own. In this study, E. photiniae was described from leaves of Photinia serratifolia in China. Based on the phylogenetic analyses using sequences of five genes (ITS, LSU, tef1, tub2 and rpb2), the new species is full supported (BYPP = 1 and ML-BS = 100%, Fig. 1) within Ellipsoidisporodochium and close to Oblongisporothyrium castanopsidis. In morphology and molecular data, the conidia of E. photiniae are smaller than those of O. castanopsidis (9–13 × 5–8 μm vs. 14–17 × 7–10 μm) and different nucleotides in the concatenated alignment (52/ 599 in the ITS, 9/ 858 in the LSU, 91/ 467 in the tef1, 49/ 520 in the tub2 and 116/ 897 in the rpb2).Published as part of Liu, Shu-Bin, Zhang, Zhao-Xue, Liu, Rong-Yu, Mu, Tai-Chang, Zhang, Xiu-Guo, Li, Zhuang & Xia, Ji-Wen, 2022, Morphological and molecular identification of Ellipsoidisporodochium gen. nov. (Tubakiaceae, Diaporthales) in Hainan Province, China, pp. 259-266 in Phytotaxa 552 (4) on pages 262-263, DOI: 10.11646/phytotaxa.552.4.3, http://zenodo.org/record/678582
- …
