310,413 research outputs found
Finite-Time H∞ Filtering for T-S Fuzzy Discrete-Time Systems with Time-Varying Delay and Norm-Bounded Uncertainties
No full textIn this paper, we investigate the filtering problem of discretetime Takagi–Sugeno (T–S) fuzzy uncertain systems subject to time-varying delays. A reduced-order filter is designed. With the augmentation technique, a filtering error system with delayed states is obtained. In order to deal with time delays in system states, the filtering error system is first transformed into two interconnected subsystems. By using a two-term approximation for the time-varying delay, sufficient delay-dependent conditions of finite-time boundedness andH∞ performance of the filtering error system are derived with the Lyapunov function. Based on these conditions, the filter design methods are proposed and the filter gain matrices can be obtained by calculating a set of linear matrix inequalities. A numerical example is used to illustrate the effectiveness of the proposed approaches.Zhuo Zhang, Zexu Zhang, Hui Zhang, Peng Shi, and Hamid Reza Karim
Whittieria engelmannii Li Bing Zhang & Liang Zhang ex Li Bing Zhang, Liang Zhang & X. Wan 2022, comb. nov.
No full textWhittieria engelmannii (Prantl 1883: 351) Li Bing Zhang & Liang Zhang ex Li Bing Zhang, Liang Zhang & X.Wan, comb. nov. Basionym: Ophioglossum engelmannii Prantl (1883: 351) ≡ “ Whittieria engelmannii (Prantl) Li Bing Zhang & Liang Zhang ” (2022: 24), nom. inval. Type:— U.S.A. Texas: Comanche Spring, New Braunfels, May 1849, F.J. Lindheimer 1281 (lectotype MO201251!, here designated, isolectotypes FI003993!, K001057659!, MEXU00085077!, MEXU00000139!, TEX00348044!). Remaining syntypes: U.S.A. Texas: May 1849, F.J. Lindheimer 95 (MO251338!). U.S.A. Texas: Comanche Spring, Bexar County, May 1849, F.J. Lindheimer 53 (GH00021725!, FI003992!). Notes:— In the protologue (Prantl 1883), there were no specific gatherings cited but only “Nordamerika” (North America) was given. According to Stafleu & Cowan (1983: 379), K.A.E. Prantl’s herbarium and types are mainly at “HBG (esp. Pteridophyta)”. We searched the database of HBG (www.herbariumhamburgense.de), and only found three gatherings of Ophioglossum from Namibia and South Africa. In Tropicos (tropicos.org), four gathering are indicated as “T” (type) or “ST” (syntypes). We found three of the four gatherings in various herbaria (see above) in JSTOR (plants.jstor.org) but could not find Engelmann s.n collected before 1883. We here designated the one of the duplicates of F.J. Lindheimer 1281 at MO as the lectotype. This species has three unique features: growing in basic soils, double venation (large areoles of the sterile blade subdivided into smaller areoles; Wagner & Wagner 1994), and 71 days of spore germination time (Whittier 1981, Zhang & Zhang 2022). Distribution:— United States, Mexico, and Central America.Published as part of Wan, Xia, Zhang, Liang & Zhang, Li-Bing, 2022, Validation and lectotypification of the fern combination Whittieria engelmannii (Ophioglossaceae), pp. 205-206 in Phytotaxa 567 (2) on pages 205-206, DOI: 10.11646/phytotaxa.567.2.10, http://zenodo.org/record/714165
Holotype of <i>Mazus sunhangii</i> D. G. Zhang & T. Deng.
No full textHolotype of Mazus sunhangii D. G. Zhang & T. Deng.</p
The mitochondrial genome of Lamellomphalus manusensis Zhang & Zhang, 2017 (Gastropoda: Neomphalida) from deep-sea hydrothermal vent
No full textWe report the nearly complete mitochondrial genome sequence of Lamellomphalus manusensis Zhang and Zhang 2017, a deep-sea snail inhabiting hydrothermal vent. The mitogenome is 15,990 bp in length, has a base composition of A (35.7%), T (33.5%), C (15.4%) and G (15.4%), and contains 13 protein-coding genes, 2 ribosomal RNA genes, and 22 tRNA genes. Phylogenetic analyses show that the family Peltospiridae is not monophyletic, suggesting that its genera need to be redefined
Sinojassus compressus Dai, Zhang and Zhang, sp. nov.
No full textSinojassus compressus Dai, Zhang and Zhang sp. nov. Figs 3, 6, 9, 36– 43. Male 5.8 mm long, 2.2 mm wide across eyes and 2.5 mm wide across hind margin of pronotum. Proportion of width of head including eyes to hind margin of pronotum is 0.86. Pale greenish brown with brown spots. Forewings brown and legs yellowish brown. Male genitalia: Caudal margin of pygofer convexly rounded, with many macrosetae on caudal margin. Subgenital plate short, apex rounded, with lateral marginal setae. Style narrow and long, apophysis curved at an obtuse angle, with tooth-like projection at base of apophysis both dorsally and ventrally in lateral view, apex curved ventrally and rounded. Aedeagus with well developed bifid dorsal apodeme, preatrium not developed, shaft stout, compressed, in lateral view widened near midlength and slightly curved dorsally near apex, with lateral spicules preapically. Material examined. Holotype 3, China, Yunnan Prov., Simao, 7 April 1981, Li Fasheng (CAU). Paratypes: 13, Thailand, Chiang Mai, Doi Chiang Dao WS Nature Trail, 19 º 24.187 'N 98 º 55.312 'E, 491m, Malaise trap 31.vii- 7.viii. 2007, Songkrant Jagsu & Apichat Watwanich, T 2829 (QSBG); 13, Thailand, Chiang Mai, Doi Chiang Dao WS Nature trail, 19 º 24.278 'N 98 º 55.311 'E, 491m, Malaise trap 30.ix- 7.x. 2007, Songkran & Apichart, T 3174 (INHS). Remarks. This species resembles Sinojassus aspinus sp. nov. externally but can be distinguished from the latter by the pygofer with many macrosetae on the caudal margin and the compressed aedeagal shaft. Etymology. The name of the species refers to the compressed aedeagal shaft.Published as part of Dai, Wu, Zhang, Xinmin & Zhang, Yalin, 2010, A new Oriental genus of Iassini leafhoppers (Hemiptera: Cicadellidae: Iassinae) with description of four new species, pp. 15-26 in Zootaxa 2641 on pages 22-23, DOI: 10.5281/zenodo.19859
The liberation of light
No full textFor more than a century, light has come from glass shell. But it won’t for much longer, believes Prof. GQ (Kouchi) Zhang. “Light emitting diodes are going to liberate light.”Electrical Engineering, Mathematics and Computer Scienc
Taira concava Zhang, Zhu & Song 2008
No full textTaira concava Zhang, Zhu & Song, 2008 Figures 4, 24 Taira concava Zhang et al., 2008: 506, figs 17–21 (♂ ♀); Zhu et al. 2017: 577, figs 376A–E (♂ ♀). Type material: Holotype ♂ (SWUC-T-AM-04-01), 1 ♀ paratype (SWUC-T-AM-04-02), CHINA, Sichuan, Mt. Emei, 29°33.506′N 103°20.830′E, 1811 m, 16.IX.2004, Z.S. Zhang, examined. Material examined. 4 ♂ and 5 ♀ (SWUC), Mt. Emei, Jiulinggang, 13.IV.2018, Z.S. Zhang, L.Y. Wang and Z.S. Wu. Diagnosis. Males of this species resemble T. sulciformis males by having a groove present on the interior branch of the dorsal tibial apophysis and a similar sclerotized tegular apophysis in the palp (Figs 4C–E), and females resemble T. sulciformis females by having oval spermathecae in the epigyne (Figs 4F, G). T. concava, however, can be distinguished from T. sulciformis by the following characters: interior branch of the dorsal tibial apophysis narrower in T. concava (Figs 4C, E) than in T. sulciformis; retrolateral tibial apophysis with a blunt end in T. concava, whereas degenerated in T. sulciformis; median lobe of epigyne wider than long in T. concava (Fig. 4F), whereas longer than wide in T. sulciformis. Description. See Zhang et al. (2008). Habitus, male palp and epigyne (Fig. 4). Distribution. China (Sichuan) (Fig. 24).Published as part of Zhao, Jing-Xia, Wang, Lu-Yu, Irfan, Muhammad & Zhang, Zhi-Sheng, 2021, Furtherrevisionofthemesh-webspidergenus TairaLehtinen, 1967 (Amaurobiidae) with the description of six new species, pp. 457-488 in Zootaxa 5020 (3) on pages 460-461, DOI: 10.11646/zootaxa.5020.3.3, http://zenodo.org/record/522357
Cyrtomium calcis Liang Zhang, N. T. Lu & Li Bing Zhang 2023, sp. nov.
No full textCyrtomium calcis Liang Zhang, N.T.Lu & Li Bing Zhang, sp. nov., Fig. 1 Type:— VIETNAM. Hagiang Province: Vi Xuyen District, Tung Ba Community, Du Gia National Park (Khau Ca Nature Reserve), Hom Mountain, 22°50’40’’N, 105°07’47’’E, elev. ca. 1150 m, on the top of limestone mountain, 13 December 2013, Li Bing Zhang, Liang Zhang & Ngan T. Lu 6932 (holotype VNMN!; isotypes CDBI!, MO!). Diagnosis: This species is most similar to Cyrtomium pachyphyllum (Rosenstock 1914: 130) C.Christensen (1917: 11) in having erect rhizomes, dense, concolorous, and fimbriate-dentate scales throughout fronds, leathery lamina, ovate pinnae, and dentate indusia, but the new species has ovate scales on stipe base (vs. lanceolate scales in C. pachyphyllum), lanceolate-oblong lamina (vs. oblong lamina in C. pachyphyllum), up to 14 pairs of pinnae (vs. often 1–5 pairs in C. pachyphyllum), lowest pinnae shorter than the middle ones (vs. similar in C. pachyphyllum), fewer rows of areolae (2–(4)) in venation structure (vs. up to 5 rows of areolae in C. pachyphyllum). Plants terrestrial, perennial, evergreen. Rhizome erect, densely covered with ovate, lanceolate, linear, brown scales. Stipe stramineous, 15 cm long, 1–3 mm in diam., base densely scaly, scales membranous, concolorous, reddish-brown, ovate, lanceolate or linear (6–20 × 0.3–4.4 mm), fimbriate-dentate, apex long acuminate or slight twist; upward densely scaly, scales brown, narrow lanceolate, linear (2.5–6.0 × 0.1–0.7 mm). Lamina 1-imparipinnate, lanceolate-oblong (13–23 × 1.9 cm), base cordate to hastate, apex acute to slight acuminate, thick leathery; rachis ca. 1.5 mm in diam. with dense scales abaxially and adaxially, scales similar to scales on distal stipe but smaller (1–1.5 × 0.05–0.5 mm); pinnae alternate, 9 to 14 pairs, short-stalked or nearly sessile, ovate (1.5–3.5 × 1.2–1.9 cm), both adaxial and abaxial sides with microscales, glossy adaxially, margin entire, acroscopic base auriculate, blunt auricle, auricle overlap each other, apex acute; lowest pinnae shorter than middle ones, upper pinnae ovate, up to 3.5 × 1.9 cm; terminal pinna deltoid-ovate (1.5–2.5 cm); venation pinnate, obscure, veinlets form 2, 3, rarely to 4 rows of areola, each areolae with 1 included veinlet. Sori rounded (ca. 1.5 mm in diam.), 1–25 or more per pinna, 1 or 2(–3) rows on each side of midrib; indusia orbicular (1.3–1.9 mm in diam.), dentate; spores large, ellipsoid (54–60.6 µm in diam.), inflated tuberculate folds, plain exospore. Etymology:— The specific epithet, calcis, is formed from the Latin word calcis, relating to lime. It refers to the limestone habitat of this new species. Geographical distribution and habitat:— Types were collected from a limestone peak in primary evergreen broad-leaved forests in Khau Ca Nature Reserve, Vi Xuyen District, Hagiang Province. Community is composed of some taxa accompanying the new species as Cyrtomium hemionitis Christ (1910: 138), Polystichum minimum (Y.T. Hsieh 1989: 17) Li Bing Zhang (2012: 58), P. auriculum Ching (1949: 309), an Ericaceae, a Lauraceae, and an Orchidaceae. Two small populations of the new species were also found in Guangxi, China. Provisional conservation status:— Only a few mature individuals of Cyrtomium calcis were seen in the type locality although a few field investigations have been conducted by Vietnamese colleagues and the first author since 2013. Two populations in Guangxi, China were quite small and the three localities in China and Vietnam are only about 92 km in air distance. Based on current information and following the IUCN Guidelines (IUCN 2022), the new species is temporarily assessed as Critically Endangered C 2a (i, ii). Additional material examined:— CHINA. Guangxi: Napo County, elev. ca, 1300 m, 17 June 1982, Ding Fang, Mao-Xiang Lai & Zhen-Gang Wang 25384 (GXMI); elev. ca. 1250 m, 17 July 1985, Ding Fang & De-Hai Tan 79661 (GXMI). Tianlin County, elev. ca. 1490 m, 29 January 2016, S.L. Jin JSL3613 (CSH, paratype). Notes:— Cyrtomium calcis is endemic to the limestone areas, but it is not closely related to other species endemic to limestone areas, e.g., C. hemionitis, C. nephrolepioides (Christ 1902: 258) Copeland (1929: 136), C. pachyphyllum, and C. shingianum H.S.Kung & P.S.Wang (1997: 23), as shown in our phylogenetic tree (Fig. 2). The phylogenetic relationships of C. calcis are quite isolated and it is resolved as one of the earliest diverging lineages. Therefore, the discovery of C. calcis is quite significant in studying the phylogeny and evolution of the genus. Morphologically, the limestone species of Cyrtomium share a distinct morphological feature, the presence of the cordate pinna base (except C. chingianum P.S.Wang 1997: 24) (Lu & Cheng 2003, Zhang & Barrington 2013) and the new species bears gross morphological features that are consistent with those in other limestone species, e.g., thicker pinna texture, fewer pairs of pinnae per frond, broader pinnae, and more rows of areolae in venation structure (Mitsuta 1977, Lu & Cheng 2003, Zhang & Barrington 2013). The fact that C. calcis is not closely related with other limestone species in the genus suggests that these morphological similarities are homoplasious. The discovery of Cyrtomium calcis is also contribution to the limestone flora in northern Vietnam that is currently not well understood (e.g., Lu et al. 2014, also see below).Published as part of Lu, Ngan Thi, Wei, Hong-Jin, Vuong, Luong Dinh, Toan, Le Chi, Zhang, Li-Bing & Zhang, Liang, 2023, Cyrtomium calcis sp. nov. and six new records of the shield fern family (Dryopteridaceae) from Vietnam, pp. 15-26 in Phytotaxa 583 (1) on pages 16-18, DOI: 10.11646/phytotaxa.583.1.2, http://zenodo.org/record/760903
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