475 research outputs found
Mirabythus Cai, Zhao, Shih & Ren, 2012, gen. nov.
No full textKey to species of Mirabythus gen. nov. 1. Head with anterior width nearly equal to posterior width; cell 1 M with its sides parallel; propleura forming a neck, converging anteriorly in dorsal view; metanotum with a narrow transverse band slightly prolonged posteriorly.... M. lechrius sp. nov. - Head with anterior width well over half of posterior width; cell 1 M with its sides slightly convergent apically; propleura forming a neck, broadly rounded anteriorly in dorsal view; metanotum very short, roughly U-shaped in dorsal aspect....... M. liae sp. nov.Published as part of Cai, Yaping, Zhao, Yunyun, Shih, Chungkun & Ren, Dong, 2012, A new genus of Scolebythidae (Hymenoptera: Chrysidoidea) from the Early Cretaceous of China, pp. 56-66 in Zootaxa 3504 on page 63, DOI: 10.5281/zenodo.21384
Four positive periodic solutions of a discrete time Lotka-Volterra competitive system with harvesting terms
No full textTyt. z nagł.References p. 266-267.Dostępny również w formie drukowanej.ABSTRACT: In this paper, by using Mawhin's continuation theorem of coincidence degree theory, we establish the existence of at least four positive periodic solutions for a discrete time Lotka-Volterra competitive system with harvesting terms. An example is given to illustrate the effectiveness of our results. KEYWORDS: discrete systems, Lotka-Volterra competitive models, coincidence degree, harvesting terms
FIGURE 4 in A new genus of Scolebythidae (Hymenoptera: Chrysidoidea) from the Early Cretaceous of China
No full textFIGURE 4. Scolebythidae gen. et sp. indet., ventral view, under alcohol; A. CNU-HYM-LB2012107, B. CNU-HYM- LB2012108.Published as part of Cai, Yaping, Zhao, Yunyun, Shih, Chungkun & Ren, Dong, 2012, A new genus of Scolebythidae (Hymenoptera: Chrysidoidea) from the Early Cretaceous of China, pp. 56-66 in Zootaxa 3504 on page 63, DOI: 10.5281/zenodo.21384
Mirabythus Cai, Shih et Ren, gen. nov.
No full textGenus Mirabythus Cai, Shih et Ren, gen. nov. Type species Mirabythus lechrius Cai, Shih et Ren, sp. nov., designated here. Etymology. The generic name is a combination of mira – (Greek, meaning “special”) and – bythus (root of the type genus for the family, Scolebythus). Diagnosis. Medium-sized wasps, head nearly rounded. Frontal prominence absent, clypeus short, conspicuously transverse. Eyes small or moderate size, ocellar triangle obtuse, surpassing upper tangent of compound eyes. Mandible short and broad with notches on the anterior margin. Occipital carina present. Pronotal collar absent, dorsal surface of pronotum shortened. Propleura well developed, anteriorly forming a short neck. Notauli present. Prosternum large, exposed, diamond-shaped. Parapsidal lines absent. Mesoscutum separated from mesoscutellum by a straight transverse furrow. Mesosternal region large, separated by a longitudinal groove. Metanotum very short. Propodeum with median longitudinal groove extending from anterior margin to near posterior rim. Metasoma with six exposed sternites and seven exposed tergites. Fore wing cells 1 Cu, 2 Cu, R, 1 M, 2 R 1, and 1 R 1 closed; cell 1 R 1 not enlarged, shorter in length than cell 2 R 1, nearly equal to cell 1 M; R 1 present and fusing with Rs apically; pterostigma relatively small, slightly convex on costal margin; r-m crossvein present, nebular; 2 cu-a crossvein present, nebular; Cu vein present beyond 2 cu-a crossvein. The new genus is assigned to Scolebythidae due to the following characters: enlarged and exposed diamondshaped prosternum and posteriorly produced fore coxae bearing trochanters laterally. These are unique apomorphies of this family. The characters that crossvein r-m present and notches on the anterior margin of mandible are different from those of all other genera of Scolebythidae. Furthermore, vein R 1 of fore wing present, fusing with Rs apically differentiates Mirabythus gen. nov. from other genera except for three extant genera Ycaploca Nagy, Scolebythus Evans, and Clystopsenella Kieffer in the family of Scolebythidae, but the characters that cell 1 R 1 short, not longer than cell 1 M in length, Cu vein present beyond crossvein 2 cu-a are different from these three extant genera. Besides, Mirabythus gen. nov. differs from Ycaploca by the characters that cell 1 R 1 not enlarged, shorter in length than cell 2 R 1, frontal prominence absent, ocellar triangle obtuse, parapsidal line absent; from Scolebythus by the characters that median ocellus apparently surpassing upper tangent of compound eyes, parapsidal lines absent; and from Clystopsenella by the characters that occipital carina present, apex of cell 2 R 1 not arching away from anterior margin of fore wing; abdomen robust, the fifth sternite not swollen posteriorly. Species included. Type species and Mirabythus liae sp. nov.Published as part of Cai, Yaping, Zhao, Yunyun, Shih, Chungkun & Ren, Dong, 2012, A new genus of Scolebythidae (Hymenoptera: Chrysidoidea) from the Early Cretaceous of China, pp. 56-66 in Zootaxa 3504 on page 58, DOI: 10.5281/zenodo.21384
Mirabythus lechrius Cai, Shih et Ren, sp. nov.
No full textMirabythus lechrius Cai, Shih et Ren, sp. nov. (Figs 1, 3 A) Diagnosis. Head with anterior width nearly equal to posterior width. Propleura forming a strong, anterior neck, exposed dorsally, converging anteriorly in dorsal view. Posterior border of mesoscutellum not arching posteriorly. Metanotum with a narrow transverse band, slightly prolonged posteriorly. Cell 1 M with its sides parallel, crossvein m-cu tubular, vein M exceedingly beyond crossvein m-cu. Description. Medium-sized wasps, total body length 9.2 mm; fore wing length 3.1 mm. Head. Head rounded, width 1.8 mm and length 1.9 mm. Frontal prominence absent. Clypeus short, conspicuously transverse. Mandible with notches on the anterior margin (Fig. 1 E). Minimum distance between eyes 1.4 times of the height of an eye, inner margins of compound eyes nearly parallel, closest near the middle, slightly divergent below and above. Ocelli apparently surpassing upper tangent of compound eyes. Occipital carina present. Mesosoma. Pronotal collar absent, dorsal surface of pronotum shortened, about a half of mesoscutum length. Notauli present, separate anteriorly but contiguous posteriorly. Prosternum large, exposed, diamond-shaped, width longer than length. Parapsidal lines absent. Mesoscutal- mesoscutellar sulcus transverse. The length of mesoscutum slightly shorter than the length of mesoscutellum, posterior border of mesoscutellum weakly and gently convex. Mesosternum simple, not produced backward over mid coxa. Mesosternal region large, separated by a longitudinal groove in median. Metanotum very short, with a narrow transverse band, slightly prolonged posteriorly. Propodeum with median longitudinal groove extending from anterior margin to near posterior rim. Metasoma. Abdomen large and swollen, length 5.2 mm, slight sidewall compression, first tergite anterior face not concave to fit into the propodeum. Metasomal tergites dorsally comparatively flat in cross-section but sternites somewhat convex in cross-section. No constriction between first and second abdominal segments, First sternite not prolonged backward. Leg. Fore coxae large and flattened, middle coxae and hind coxae somewhat round, hind coxae separated. Holotype. Female, No. CNU-HYM-LB 2012105 p/c, a well-preserved almost complete body with fore wing, legs and partial head. Etymology. From the Greek “lechr-” referring to the slight sidewall compression. Locality and horizon. Huangbanjigou Village, Beipiao City, Liaoning Province, China; the Early Cretaceous.Published as part of Cai, Yaping, Zhao, Yunyun, Shih, Chungkun & Ren, Dong, 2012, A new genus of Scolebythidae (Hymenoptera: Chrysidoidea) from the Early Cretaceous of China, pp. 56-66 in Zootaxa 3504 on pages 59-61, DOI: 10.5281/zenodo.21384
Scolebythidae Cai, Zhao, Shih & Ren, 2012, gen. nov.
No full textKey to genera of Scolebythidae Based on the key of Engel and Grimaldi (2007), we set up a new key to genera of Scolebythidae to include the new genus Mirabythus Cai, Shih et Ren, gen. nov. 1. Vein R 1 of fore wing present, either fusing apically or nearly meeting Rs......................................... 2 - Vein R 1 of fore wing absent, and thereby not fusing with Rs apically............................................ 6 2. R 1 and Rs fusing; pronotal collar absent.................................................................. 3 - R 1 and Rs not meeting; pronotal collar present...................................... Boreobythus Engel et Grimaldi 3. Cell 1 R 1 not enlarged, shorter in length than cell 2 R 1; frons without median prominence between antennal toruli.......... 4 - Cell 1 R 1 elongate, longer than cell 2 R 1; frons with median prominence between antennal toruli............ Ycaploca Nagy 4. Crossvein r-m absent, cell 1 R 1 longer than cell 1 M in length, Cu distad 1 m-cu nebulous or absent..................... 5 - Crossvein r-m present, cell 1 R 1 nearly equal to cell 1 M in length, Cu distad 1 m-cu tubular........... Mirabythus gen. nov. 5. Occipital carina present; malar space short, less than one-half basal mandibular width; cell 2 R 1 apex situated along anterior wing margin; S 5 without special patches of setae............................................... Scolebythus Evans - Occipital carina absent; malar space well over one-half basal mandibular width; cell 2 R 1 apex arched away from anterior wing margin; S 5 with two patches of appressed, dense setae...................................... Clystopsenella Kieffer 6. Apical portion of Rs tubular; fore wing with or without closed cell 1 R 1.......................................... 7 - Apical portion of Rs nebulous; fore wing without closed cell 1 R 1............................................... 9 7. Fore wing without closed cell 1 R 1; dorsal-facing surface of pronotum greatly reduced, much smaller than mesoscutum.... 8 - Fore wing with closed cell 1 R 1; dorsalfacing surface of pronotum enlarged, larger than mesoscutum..................................................................................... Libanobythus Prentice et Poinar 8. Minute wasps (less than 2 mm in total length), with more typical scolebythid habitus; face without impressed medial line, without depressions lateral to antennal toruli; parapsidal lines faint but present; ocelli positioned just above upper tangent of compound eyes; one metatibial spur................................................ Uliobythus Engel et Grimaldi - Small wasps (ca. 2.6 mm total length), with bethylid-like habitus; face with strong medial line impressed from between anten- nal toruli to upper tangent of compound eyes, with gentle depressions lateral to antennal toruli; parapsidal lines absent; ocelli positioned far behind upper tangent of compound eyes; two metatibial spurs............... Zapenesia Engel et Grimaldi 9. Frontal prominence present; occipital carina present; metafemur not flattened....................... Pristapenesia Brues - Frontal prominence absent; occipital carina absent; metafemur flattened.......... Eobythus Lacau, Nel et Villemant, 2000Published as part of Cai, Yaping, Zhao, Yunyun, Shih, Chungkun & Ren, Dong, 2012, A new genus of Scolebythidae (Hymenoptera: Chrysidoidea) from the Early Cretaceous of China, pp. 56-66 in Zootaxa 3504 on page 59, DOI: 10.5281/zenodo.21384
Multi-objective imperfect maintenance for dependent competing risk systems with multiple degradation processes
No full textMultiple competing risks are one of the important topics in reliability field, especially degradation processes and random shocks. This research aims to relax the independent assumption by considering that there exist dependent relationships not only among multiple degradation measures but also between degradation measure and random shocks. In reality, many systems have multiple components with more than one degradation measure which is dependent with each other due to their interplaying functions or common usage history. Independent assumption may underestimate system reliability estimation under many cases. Random shocks will also contribute to the system failure through two ways: (1) one is working directly on the degradation processes; (2) the other is causing immediate failure to the system. We develop a new methodology to formulate the reliability prediction model for the gradually degradating systems subject to multiple dependent competing risks of degradation processes and random shocks. Two kinds of random shocks are considered: (1) fatal shocks, which fail the system immediately; (2) non-fatal shocks, which exhibit two effects on the system degradation process, including sudden degradation increment and degradation rate acceleration. The dependency between degradation processes and random shocks are modulated by a time-scaled covariate factors while the dependency among degradation processes are fitted by copula method. Also the reliability and state probability estimation for the systems are derived under the research scope of multi-state system using both analytical and Monte Carlo simulation for the dependent competing-risk systems. Different maintenance policy models involving imperefect preventive maintenance for this dependent model are introducted and compared with each other. Multi-objective optimization is applied to consider two important targets simultaneously in maintenance issues, including long-run expected cost rate and system availability.Ph. D.Includes bibliographical referencesIncludes vitaby Yaping Wan
Mathematical Modeling and Intelligent Optimization in Green Manufacturing & Logistics
No full textTo address the increasingly prominent environmental pollution and energy shortage, many countries devote themselves to green manufacturing and logistics in which some optimization problems are common and challenging, e.g., production planning and scheduling, supply chain management, location and allocation problems, vehicle routing problem, resource optimization, and pricing strategies. The present reprint contains all of the articles accepted and published in the Special Issue "Mathematical Modeling and Intelligent Optimization in Green Manufacturing & Logistics" from the MDPI Mathematics journal. This Special Issue is focused on collecting recent mathematical modeling and intelligent optimization research in green manufacturing and logistics, including operations research, game theory, (meta)heuristics, machine learning, knowledge-driven, digital twin, and so on. We hope that the scientific results presented in this reprint will serve as a valuable source of documentation and inspiration to those researching the modeling and optimization of green manufacturing and sustainable logistics
Fractal dynamics analysis of the VHF radiation pulses during initial breakdown process of lightning
No full textAuthor name used in this publication: Chen, Mingli.Author name used in this publication: Du, Yaping.2009-2010 > Academic research: refereed > Publication in refereed journalVersion of RecordRGCPolyU 512908EPublishedVoR allowe
Simultaneous observations of optical and electrical signals in altitude-triggered negative lightning flashes
No full textAuthor name used in this publication: Chen, Mingli.Author name used in this publication: Du, Yaping.2002-2003 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishedVoR allowe
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