138,955 research outputs found
Non-Foster Circuit Loaded Periodic Structures for Broadband Fast and Slow Wave Propagation
No full textCopyright Jiang Long, 2015 All rights reserved. The Dissertation of Jiang Long is approved, and it is accept-able in quality and form for publication on microfilm and electronically
Lobellina gladius Hu & Jiang & Jiang 2019, sp. nov.
No full textLobellina gladius sp. nov. Figures 2, 4, 6, 10–14, 16, 18, 20, Tables 4–5 Type material. Holotype: male, China, Hunan, Xinning county, Langshan National Geopark. Coordinates: 26.273767N, 110.732951E, alt. 770m, in forest of bamboo, leg. Ji-Gang Jiang, Cheng Jiang, Li-Ping Duan, 29.iv.2018. Paratypes: 5 females and 2 juveniles, about 30 specimens in alcohol, the same data as holotype, collection number as J2018042904. One female, subadult, and 4 juvenile, Guangxi, Ziyuan county, Langshan National Geopark. Coordinates: 26.274416N, 110.732011E, alt. 685m, in forest of bamboo, leg. Ji-Gang Jiang, Cheng Jiang, Li-Ping Duan, 29.iv.2018 (J2018042903). Female and male, Guangxi, Ziyuan county, Langshan National Geopark. Coordinates: 26.276824N, 110.730528E, alt. 510m, nearby the entrance of the Park, leg. Ji-Gang Jiang, Cheng Jiang, Li-Ping Duan, 29.iv.2018 (J2018042901). One male, Hunan, Xinning county, Shunhuangshang National Nature Reserve, Coordinates: 26.450028N, 111.014716E, alt. 930m, in forest, leg. Ji-Gang Jiang, Cheng Jiang, Li-Ping Duan, 1.v.2018 (J2018050102). Type materials are housed in the Key Laboratory of Zoology, Hunan University of Arts and Science (HUAS), Changde, Hunan Province, China. Diagnosis. Three pigmented eyes on head, mandible with six teeth, cephalic chaeta O present and including in tubercle Fr, cephalic tubercle Di not fused, non-cross type chaetotaxy on posterior area of head, cephalic lateral tubercle Dl, L and So independent respectively, Ant. I with 9 chaetae, Th. I with 4+4 tubercles, VT with 6–8 (usually 7) chaetae. Description. Body length: holotype, male, 4.0 mm. Usually, males: 4.0– 4.4 mm, females: 3.5–4.8 mm, juveniles: 1.5–3.5 mm. Body color. Red while living (Fig. 2) and white in alcohol (Fig. 4). Chaetal morphology (Fig. 6). Dorsal ordinary chaetae of four types: Ml, Mc, Mcc and me. Macrochaetae Ml long, sheathed, smooth and with blunt tip, gladius shaped (Fig. 6j), some Ml not sheathed and with pointed tip, such as F chaetae on head (Fig.6k) and macrochaetae on Abd. VI (Fig. 6l). Macrochaetae Mc similar to Ml morphologically, but shorter (Fig. 6 m–n). Macrochaetae Mcc morphologically similar to Mc and shorter than Mc (Fig. 6o). Mesochaetae similar to ventral chaetae, thin, smooth, and pointed, with various length (Fig. 6 p–r, t). S-chaetae on terga thin, smooth, equal to Mc and longer than Mcc (Fig. 6s). Head (Table 4, Fig. 10). Eyes 3+3, black (Fig. 11). Antenna 4-segmented (Fig. 16). Ant. I with 9 Chaetae. Ant. II with 9–11 Chaetae. Ant. III dorsally fused to Ant. IV. Two guard chaetae sgd and sgv present. Two short rods exposed in separate pit. Ant. IV dorsally with 8 thickened and curved sensilla, apical bulb trilobed. sensory organite (or) present. Ventral chaetotaxy of Ant. IV: ap with 7 bs and 3 miA, ca with 3 bs and 1 miA, cm with 2 bs and 2 miA, cp with 1 miA. On ventral side of Ant. III, Vi, Vc, Ve respectively with 3, 5, 4 chaetae. Buccal cone weakly developed, labrum truncated, chaetal formula as 0/2, 2. Mandible with four apical teeth, one curved middle tooth and one basal tooth (Fig. 12). Maxilla crochet form (Fig. 13). Labium with 11 chaetae and no x (Fig.18). Group Vi with 6+6 chaetae (Fig.18). Groups Vea, Vem and Vep with 5, 2 and 2 chaetae respectively. Dorsal chaetotaxy of head as in Table 4. and Fig. 10. Dorsal central area with 6 separate tubercles: 1 tubercle Cl, 2 An, 1 Fr and 2 Oc. Dorsal posterior area with 4 separate tubercles: 2 Di and 2 De. Line of chaetae Di2–De2 not crosses line Di1– De1 on head (non-cross type, Deharveng, 1983). Dorsal lateral area with 3 separate tubercles: Dl, L and So. Thorax (Table 5 & Fig. 10). Th. I with 4+4 tubercles (Di, De, Dl and L). Th. II and Th. III with 4+4 tubercles respectively. Chaetotaxy of thorax and legs as in Table 2. Unguis with a basal inner tooth, unguiculus absent. Chaeta M present on tibiotarsus. Abdomen (Table 5 & Fig. 10). Abd.I–IV respectively with 4+4 tubercles. Abd. V dorsally with 3+3 tubercles, two tubercles Di separate from each other, tubercle De separate from Dl, tubercle L present, on ventral side. Abd. VI with 1 tubercle on each side. VT with 7+7 chaetae, sometimes 6+6 or 8+8. Furcular remnant with 4 chaetae (Fig. 20). Etymology. The name of the species derives from the “ gladius ” shape of its macrochaetae. Remarks. The new species can be separated from known species by the following characters: Th. I with 4+4 tubercles; tubercle Di with 3 chaetae on Abd. I–III respectively, VT with 6–8 chaetae (usually 7); non-crossed type chaetae on cephalic posterior area. Including the new species, sixteen species of genus Lobellina are known worldwide. Seven of them have O chaeta on cephalic tubercle Fr, of which, 4 with chaeta O free from the tubercle, and three species, i.e. L. nanjingensis, L.fusa and L. gladius sp. nov. with chaeta O included in tubercle Fr. The new species can be easily differentiated from the other two species of the last group by the following key.Published as part of Hu, Ya-Hui, Jiang, Cheng & Jiang, Ji-Gang, 2019, Two new species of Lobellini from Central-South China (Collembola Neanuridae), pp. 77-89 in Zootaxa 4712 (1) on pages 83-88, DOI: 10.11646/zootaxa.4712.1.5, http://zenodo.org/record/358686
AlGaN/GaN HEMT micro-sensor technology for gas sensing applications
No full text Wide bandgap gallium nitride material has highly favorable electronic properties for next generation power and high frequency electronic devices. A less widely studied application is highly miniaturized chemical and gas sensors capable of operating in harsh environment conditions. In this work we present our recent developments on design, fabrication and testing of AlGaN/GaN high electron mobility transistor (HEMT) based sensors for detection of various gases. First, the method of as-fabricated device baseline value stabilization is demonstrated. Secondly, the impact of sensor design is discussed with the emphasis on gate electrode geometry optimizations to enhance sensing performance. Then we present the sensing characteristics of Pt-HEMTs towards H 2 S and compare them to H 2 and NO 2 . Finally we demonstrate recent results of NO 2 detection with Ti/Au based HEMT sensors, which are superior to those using Pt based devices. Accepted author manuscriptElectronic Components, Technology and Material
Crossodonthina langshanensis Hu & Jiang & Jiang 2019, sp. nov.
No full textCrossodonthina langshanensis sp. nov. Figures 1, 3, 5, 7–9, 15, 17, 19, Tables 1–3 Type material. Holotype: female, China, Hunan, Xinning county, Langshan National Geopark. Coordinates: 26.277054N, 110.730618E, alt. 520m, in forest, leg. Ji-Gang Jiang, Cheng Jiang, Li-Ping Duan, 30.iv.2018 (J2018043002). Paratypes: 2 females, China, Hunan, Xinning county, Langshan National Geopark. Coordinates: 26.276580N, 110.729240E, alt. 470m, in forest, leg. Ji-Gang Jiang, Cheng Jiang, Li-Ping Duan, 30.iv.2018 (J2018043003); 3 juvenile, Guangxi, Ziyuan county, Langshan National Geopark, Coordinates: 26.276824N, 110.730528E, alt. 510m, nearby the entrance of the Park, leg. Ji-Gang Jiang, Cheng Jiang, Li-Ping Duan, 29.iv.2018 (J2018042901). Type materials are housed in the Key Laboratory of Zoology, Hunan University of Arts and Science (HUAS), Changde, Hunan Province, China. Othermaterial. 2females, China, Hunan, Xinningcounty,LangshanNationalGeopark. Coordinates: 26.276986N, 110.736902E, alt. 527m, in forest, leg. Ji-Gang Jiang, Ya-Hui Hu, Wei Hu, 25.vii.2019 (J2019072502). Diagnosis. 2+2 black eyes on head; labral chaetotaxy as 2/4, 2; cephalic chaeta O present; tubercle Dl on Th. II with 3 chaetae (2+s); mandible with 2 prominent basal teeth and 2 fringed rami of quite different sizes; maxilla with marginal filaments on outer lamella; tubercle Di on Abd. V separated; Description. Body length: holotype 2.4 mm, two paratypes 2.3–2.4 mm, three juveniles 1.0– 1.1mm. Color. Red while living (Fig. 1) and white in alcohol (Fig. 3). Chaetal morphology (Fig. 5). Dorsal ordinary chaetae of five types: Ml (Fig. 5 a–b), Mc (Fig. 5c), Mcc (Fig. 5d), me (Fig. 5 e–f) and mi (Fig. 5h). S-chaetae on terga thin, smooth, shorter than Ml and longer than Mc (Fig. 5g). Head. Eyes 2+2, black. Antenna 4-segmented (Fig. 15). Ant. I with 9 chaetae. Ant. II with 11 chaetae. Ant. III and IV dorsally fused. Dorsal sensory guard chaeta (sgd) on Ant. III not migrated distally, two rods exposed in separate pit. Ant. IV dorsally with 8 slightly thickened and blunt sensilla, apical bulb trilobed. sensory organite (or) present. Ventral chaetotaxy of Ant. IV: ap with 8 bs and 3 miA, ca with 2 bs and 3 miA, cm with 3 bs and 1 miA, cp without miA. On ventral side of Ant. III, Vi, Vc, Ve with 3, 4, 4 chaetae respectively. Buccal cone moderately developed. Labrum truncated, chaetal formula as 2/4, 2 (adult) or 4/4, 2 (juvenile). Labium with 11 chaetae and 2 x (Fig. 17). Mandible complicated (Fig. 8), consisting of 2 rami, 2 definite teeth and some spine-like chaetae. Small ramus consisting of one spine-like chaeta and 7–8 slender chaetae, large ramus developed, with 2 rows of marginal chaetae, 4 strong and spine-like chaetae, marginal chaetae on ramus simple, bifurcated or tri-furcated, about 9-12 spine-like chaetae present on the central area of basal part of the large ramus. The longer ramus about 10 times as long as the small one. Maxilla consisting of two lamellae, the inner lamella much shorter than the outer one, with two minute apical teeth, the outer one with marginal filaments on inner side (Fig. 9). On ventral side of head, group Vi with 6+6 chaetae, groups Vea, Vem and Vep with 4, 3 and 2 chaetae respectively. Dorsal tubercles and chaetotaxy of head as in Tab. 1. and Fig. 7. Dorsal central area with 6 separate tubercles; one tubercle Cl, 2 An, one Fr and 2 Oc, chaeta O absent. Dorsal posterior area with 4 separate tubercles: 2 Di and 2 De. Line of chaetae Di2–De2 crosses line Di1– De1 on head (cross-type, Deharveng 1983). Dorsal lateral area with 1 fused tubercle (Dl+L+So). Thorax (Table 2 & Fig. 7). Th. I with 3+3 tubercles (Di, De, Dl). Th. II and Th. III with 4+4 tubercles respectively, ms on tubercle Dl of Th. II present (its form as in Fig. 5i). Chaetotaxy of thorax and legs as in Table 2. Unguis with a basal inner tooth, unguiculus absent. Chaeta M present on tibiotarsus. Abdomen (Table 2 & Fig. 7). Abd. I–IV respectively with 4+4 tubercles. Abd. V dorsally with 2+2 tubercles, two tubercles Di close to each other, but not fused together, tubercle De fused to Dl, tubercle L present on ventral side. Abd. VI with 1 tubercle on each side, no cryptopygy. VT with 4+4 chaetae. Furcular remnant with 3-4 chaetae (Fig. 19). Etymology. The name of the species derives from the locality where it was collected. Ecology. Among decayed leaves in forest. Remarks. So far, 12 species of genus Crossodonthina were reported worldwide, 11 species were from Asia and only one from Oceania, seven species were reported from China (Jiang & Zhang, 2012). In genus Crossodonthina, three species have 2+2 eyes, they are C. bidentata, C. hainana and C. montana, the new species is the fourth one with 2+2 eyes. In general appearance, Crossodonthina langshanensis sp. nov. strongly resembles Chinese species C. bidentata (Luo & Chen, 2009) in the number of mandible basal teeth, the arrangement of body tubercles, the presence of chaeta O of tubercle Fr, the number of chaetae on VT, and the presence of inner tooth on claw. However, these species can be distinguished by the following features: structure of mandible (in C. langshanensis with two fringed rami, in C. bidentata with three fringed rami), structure of maxilla (in C. langshanensis outer lamella fringed, in C. bidentate outer lamella not fringed), whether the tubercle Di fused on Abd. V or not (in C. langshanensis not fused, in C. bidentate fused), the labral chaeta formula (in C. langshanensis 2/4, 2, in C. bidentata 2/5, 2), number of chaetae (besides of ms) on tubercles Dl of Th. II (in C. langshanensis 3, in C. bidentata 4). The new species is also similar to the 2+2-eyed Chinese species C. montana (Lee & Kim, 1990) and C. hainana (Xiong et al., 2005) in the arrangement of body tubercles, the presence of chaeta O of tubercle Fr, the separate tubercle Di of Abd. V and the presence of 4+4 chaetae on VT. The new species can be separated from the above species by the characters listed in Table 3.Published as part of Hu, Ya-Hui, Jiang, Cheng & Jiang, Ji-Gang, 2019, Two new species of Lobellini from Central-South China (Collembola Neanuridae), pp. 77-89 in Zootaxa 4712 (1) on pages 78-82, DOI: 10.11646/zootaxa.4712.1.5, http://zenodo.org/record/358686
Zamilia arkari Jiang & Li 2022, sp. nov.
No full textZamilia arkari Jiang & Li, sp. nov. (Figs 4–6) Holotype. Male (IZCAS-Ar42684Fo). Late Cretaceous amber from Hukawng Valley. No biotic syninclusions. Etymology. The species name is a popular Burmese boy’s name and means “sky”; noun in apposition. Diagnosis. Zamilia arkari Jiang & Li, sp. nov. resembles Z. quattuormammillae Wunderlich, 2015 (see Wunderlich, 2015: 296, figs 300–309, photo 147) by the trapeziform median apophysis. Z. quattuormammillae has a tegular apophysis in addition to the median apophysis, while the new species does not have. Description. Male. Total length 3.80; carapace 1.55 long, 1.44 wide; opisthosoma 2.25 long, 1.25 wide. Left palp: - (0.66 + 0.32 + -), left leg I: 7.08 (2.09 + 0.62 + 1.73 + 1.87 + 0.77), leg II: 7.84 (2.82 + 0.71 + 1.52 + 1.90 + 0.89), leg III: - (2.02 + 0.69 + - + - + -), leg IV: 6.75 (1.86 + 0.52 + 1.34 + 2.09 + 0.94); right palp: - (0.78 + - + -), right leg I: 6.80 (1.88 + 0.59 + 1.62 + 1.81 + 0.90), leg II: 7.08 (1.93 + 0.72 + 1.71 + 1.89 +0.83), leg III: 5.71 (1.75 + 0.66 + 1.52 + 1.03 + 0.75), leg IV: - (1.93 + 0.48 + 1.47 + 1.79 + -). Eye sizes and interdistances: ALE 0.08, AME 0.08, PLE 0.09, PME 0.04; AME– AME 0.04, AME–ALE 0.02, PME–PLE 0.06, PME–PME 0.19. Habitus as in Figs 5A–B. Carapace almost round, longer than wide, yellow. Sternum oval, yellow, with dense brown setae. Metatarsi with 2 distal spines. Opisthosoma elongate. Anterior lateral spinnerets (Fig. 5D) short, posterior spinnerets with terminal segment long, ca. 0.63, basal segment short, ca. 0.20; anal tubercle fringed with long setae. Palp (Figs 4A–D, 6). Ratio of femur length to cymbial length 1.27, femur width 0.22, cymbium oval, longer than wide; median apophysis elongate, bent distally.Published as part of Xin, Yafei, Jiang, Tongyao, Yao, Zhiyuan & Li, Shuqiang, 2022, Twenty new spider species (Arachnida: Araneae) from Late Cretaceous Kachin amber (Myanmar), pp. 1-65 in Zoological Systematics 47 (1) on page 3, DOI: 10.11865/zs.2022101, http://zenodo.org/record/717614
Zamilia sheini Jiang & Li 2022, sp. nov.
No full textZamilia sheini Jiang & Li, sp. nov. (Figs 7–9) Holotype. Male (IZCAS-Ar42685Fo). Late Cretaceous amber from Hukawng Valley. Syninclusions include one mite and two dipterans. Etymology. The species name is a popular Burmese boy’s name and means “reflection”; noun in apposition. Diagnosis. Zamilia sheini Jiang & Li, sp. nov. can be distinguished from its congeners by a flake-shaped median apophysis and a membranous conductor. It can be distinguished from Z. quattuormammillae Wunderlich, 2015 (see Wunderlich, 2015: 296, figs 300–309, photo 147) by the triangular median apophysis and the smooth clypeal margin, while Z. quattuormammillae has a nose-shaped apophysis on the clypeus and a curved median apophysis. Description. Male. Total length 1.97; carapace 0.74 long, 0.91 wide; opisthosoma 1.23 long, 1.01 wide. Left palp: - (- + 0.21 + -), left leg I: - (- + - + - + 0.89 + 0.45), leg II: - (- + - + - + 0.84 + 0.40), leg III: - (- + - + - + 0.76 + 0.40), leg IV: - (- + - + - + 0.83 + 0.47); right palp: - (0.67 + - + -), right leg I: - (- + - + - + 0.83 + 0.36), leg II: - (0.79 + - + - + 0.81 +0.40), leg III: - (0.81 + - + - + 0.77 + 0.38), leg IV: - (- + - + - + 0.75 + 0.44). Eye sizes and interdistances: ALE 0.05, AME 0.07, PLE 0.07, PME 0.06; AME–AME 0.04, AME–ALE 0.02, ALE–PLE 0.05, PME–PLE 0.01, PME–PME 0.05. Habitus as in Figs 8A–B. Carapace almost round, yellowish. Sternum round, yellowish with dense brown setae. Legs have two spines distally on metatarsus and tarsus, 3 claws. Opisthosoma round. Anterior lateral spinnerets (Fig. 8D) short, posterior spinnerets with terminal segment long, ca. 0.26, basal segment short, ca. 0.06; anal tubercle fringed with long setae. Palp (Figs 7A–D, 9). Ratio of femur length to cymbial length 2.57, femur width 0.09, cymbium round, length equal to width; embolus slightly flattened, flake-shaped; median apophysis triangular.Published as part of Xin, Yafei, Jiang, Tongyao, Yao, Zhiyuan & Li, Shuqiang, 2022, Twenty new spider species (Arachnida: Araneae) from Late Cretaceous Kachin amber (Myanmar), pp. 1-65 in Zoological Systematics 47 (1) on pages 3-12, DOI: 10.11865/zs.2022101, http://zenodo.org/record/717614
Tychius zhangi Jiang & Caldara 2020, n. sp.
No full text30. Tychius zhangi Jiang & Caldara n. sp. Zoobank.org/ urn:lsid:zoobank.org:act: 0E8C0D6B-E580-43DE-990F-5DC4A26695DC (Figures 97–100, 219–222, 295–296, 333, 346, 358, 389, 425, 453, 480) Material examined. Holotype, male, CHINA: Xinjiang: Tulufan, (20–140 m), 24-VI-1958, leg Guang Wang (IOZCAS). Paratypes, same data as holotype (2 IOZCAS); Jiashi (1160 m), 20-VI-1959, leg Afu Tian (1 IOZCAS); Hejing, 26-VII-1958, leg Changqing Li (1 IOZCAS). Diagnostic description. Length 1.90–2.50 mm (Fig. 97–100). Vestiture on dorsum grayish unicolorous. Rostrum (Fig. 219–222) moderately long, poorly sexually dimorphic, slightly longer in female than in male (Rl/Rw 5.30–5.50 in male, 7.00– 7.50 in female; Rl/Pl 0.88–0.92 in male, 0.93–0.94 in female), thin, in lateral view curved at base, then almost straight to apex. Pronotum (Pw/Pl 1.10–1.17) with slightly rounded sides from base to apex, slightly wider than long. Elytra suboval (Ew/Pw 1.26–1.36; El/Ew 1.50–1.69), with slightly rounded sides in basal half. Femora (Fig. 295–296) unarmed, tibiae (Fig. 333) without sexual characters. Third tarsomere moderately wider than second tarsomere (Fig. 346). Claws (Fig. 358) with small medial teeth as long as 1/3 of claw, separated from claw from base. Male genitalia: body of penis (Fig. 389) in dorsal view moderately large, parallel-sided near to apex, with acutely pointed apex (Fig. 425), in lateral view strongly curved and very subtle, nearly as long as apodeme. Female genitalia: spermatheca see Fig. 453; spiculum ventrale (Fig. 480) with thin arms spaced in basal third but distinctly narrowing to middle, then completely joined to apex. Remarks and comparative notes. This species is closely related to T. tachengicus and T. sulphureus. Tychius zhangi differs by the rostrum of both sexes being longer and that of the female in lateral view of the same width from the antennal insertion to the apex and not distinctly narrowed. The medial teeth of the claw are distinctly smaller and shorter than in the other two species. Finally, the body of the penis in dorsal view is moderately large, parallelsided near to apex, with acutely pointed apex, in lateral view strongly curved and very subtle, nearly as long as an apodeme. Etymology. The name of this species is the family name of our corresponding author Prof. Runzhi Zhang. We would like to thank him for supporting our work in weevil taxonomy. Biology. No data are available. Distribution. China (XIN)Published as part of Jiang, Chunyan, Caldara, Roberto & Zhang, Runzhi, 2020, The genus Tychius Germar (Coleoptera: Curculionidae: Curculioninae) in China, with description of three new species, pp. 1-62 in Zootaxa 4856 (1) on pages 32-33, DOI: 10.11646/zootaxa.4856.1.1, http://zenodo.org/record/441131
A reliability-centred maintenance strategy based on maintenance free operating period philosophy and total lifetime operating cost analysis
No full textMaintenance intervention is necessary for the equipment, such as aircraft structures and systems, to maintain their operational performance status during their lifetime. Generally maintenance costs make a significant contribution to overall operating costs. Accordingly, developing an optimal maintenance strategy to minimize maintenance costs and total lifetime operating cost (TLOC) is a critical task.This article proposes a methodology for the optimization of a reliability-centred maintenance strategy based on maintenance-free operating period (MFOP) philosophy by considering the TLOC. The method can be used to evaluate the TLOC of alternative maintenance strategies and determine the optimal maintenance interval while meeting the proposed reliability requirements. The method is also suitable for evaluating and optimizing the MFOP-based reliability design of the products. An example based on line replaceable unit replacement strategy is introduced to illustrate the proposed maintenance strategy optimization approach. And a sensitivity analysis on the TLOC index for each of the two reliability requirement parameters is also performed
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