196,647 research outputs found
Refinamentos para o método dos tableaux /
No full textDissertação (Mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico.No presente trabalho são propostos refinamentos sobre o método dos tableaux, tal como tradicionalmente apresentado, visando diminuir o número de nós das árvores de prova, bem como aumentar a possibilidade de obtenção de respostas. Para isto especificamos e implementamos três diferentes algoritmos baseados no método tradicional dos tableaux para a lógica clássica. O mais sofisticado e avançado dos três métodos recorre ao procedimento de unificação, comumente utilizado no método da resolução. Finalizamos este trabalho apresentando uma série de testes, para verificar experimentalmente a consecução dos objetivos propostos
[[alternative]]Computations of Samuel- multiplicities and Buchsbaum-Rim multiplicities
No full text[[abstract]]Let (R,m) be a Noetherian local ring of dimension d and let I be an ideal of R such that R/I has finite length. Then there exists a polynomial g(n) of degree d such that g(n)=l(R/I^n) for large n. The coefficient of n^d/d! in g(n) is the Samuel-multiplicity. The Buchsbaum-Rim multiplicity id defined for a sumodule M of a free module F=R^r such l(F/M) is finite and M is contained in mF. Then there exists a polynomial Q(n) of degree d+r-1 such that Q(n)=l(S_n(F)/R_n(M)) for large n. The Buchsbaum-Rim multiplicity of M is the coefficient of n^d+r-1/(d+r-1)! in Q(n).
Buchsbaum–Rim multiplicities as Hilbert–Samuel multiplicities
No full textAbstractWe study the Buchsbaum–Rim multiplicity br(M) of a finitely generated module M over a regular local ring R of dimension 2 with maximal ideal m. The module M under consideration is of finite colength in a free R-module F. Write F/M≅I/J, where J⊂I are m-primary ideals of R. We first investigate the colength ℓ(R/a) of any m-primary ideal a and its Hilbert–Samuel multiplicity e(a) using linkage theory. As an application, we establish several multiplicity formulas that express the Buchsbaum–Rim multiplicity of the module M in terms of the Hilbert–Samuel multiplicities of ideals related to I, J and a minimal reduction of M. The motivation comes from work by E. Jones, who applied graphical computations of the Hilbert–Samuel multiplicity to the Buchsbaum–Rim multiplicity [E. Jones, Computations of Buchsbaum–Rim multiplicities, J. Pure Appl. Algebra 162 (2001) 37–52]
On the Buchsbaum Property of Associated Graded Rings
No full textAbstractLetIbe an m-primary ideal in a Buchsbaum local ring (A,m). In this paper, we investigate the Buchsbaum property of the associated graded ring ofIwhen the equalityI2=qIholds for some minimal reduction q ofI. However, the Buchsbaum property does not always follow even ifI2=qI. So we give certain conditions for associated graded rings to be Buchsbaum in this situation
On Buchsbaum bundles on quadric hypersurfaces
No full textLet be an indecomposable rank two vector bundle on the projective space \PP^n, n \ge 3, over an algebraically closed field of characteristic zero. It is well known that is arithmetically Buchsbaum if and only if and is a null-correlation bundle. In the present paper we establish an analogous result for rank two indecomposable arithmetically Buchsbaum vector bundles on the smooth quadric hypersurface Q_n\subset\PP^{n+1}, . We give in fact a full classification and prove that must be at most . As to -Buchsbaum rank two vector bundles on , , we prove two boundedness result
Computations of Buchsbaum–Rim multiplicities
No full textAbstractThe Buchsbaum–Rim multiplicity is a generalization of the Samuel multiplicity and is defined on submodules of free modules M⊂F of a local Noetherian ring A such that M⊂mF and F/M has finite length. Let A=k[x,y](x,y) be a localization of a polynomial ring over a field. When F/M is isomorphic to a quotient of monomial ideals there is a region of the (x,y)-plane which corresponds to F/M. We wish to compute Buchsbaum–Rim multiplicity using the areas of pieces of this region in a manner similar to that used to compute the Samuel multiplicity of a monomial ideal. We carry out these computations in the case where F has rank2 and F/M≅I/J where I and J are monomial ideals, with the further restriction that I is generated by two elements and J is generated by at most three elements. We find that the Buchsbaum–Rim multiplicity is at most the difference of the Samuel multiplicities of J and I with equality often holding. When equality does not hold the Buchsbaum–Rim multiplicity is the difference of the Samuel multiplicities minus a term that can be expressed in terms of areas
Some remarks on Buchsbaum bundles
No full textAbstractLet E be a vector bundle on Pn . We say E is Buchsbaum if Hp(EM(∗)) has trivial module structure for each linear space M and for all 1≤p≤dimM−1. In this note, we show that a Buchsbaum bundle is either an Ω-bundle (i.e. a direct sum of Ωp(h)'s, where Ωp is the pth exterior power of the contangent bundle of Pn) or the quotient of an Ω-bundle by a direct sum of line bundles. We also give a strategy to characterize/construct Buchsbaum bundles, give conditions for an Ω-bundle to be extendable
Resolutions of three-rowed skew- and almost skew-shapes in characteristic zero
No full textWe fi nd an explicit description of the terms and boundary
maps for the three-rowed skew-shape and almost skew-shape in charac-
teristic zero
A note on quasi-Buchsbaum rings
No full textIn this paper the ubiquity of non-Buchsbaum but quasi-Buchsbaum rings is established. The result is stated as follows: Let
d
≥
3
d \ge 3
and
h
1
,
h
2
,
…
,
h
d
−
1
≥
0
{h_1},{h_2}, \ldots ,{h_{d - 1}} \ge 0
be integers and assume that at least two of
h
i
{h_i}
’s are positive. Then there exists a non-Buchsbaum but quasi-Buchsbaum local integral domain
A
A
of
dim
A
=
d
\dim A = d
and such that
l
A
(
H
m
i
(
A
)
)
=
h
i
{l_A}(H_m^i(A)) = {h_i}
for all
1
≤
i
≤
d
−
1
1 \le i \le d - 1
. Moreover if
h
1
=
0
{h_1} = 0
the ring
A
A
can be chosen to be normal.</p
Endoclita meifenga Buchsbaum & Grehan 2019, sp. n.
No full text<i>Endoclita meifenga</i> Buchsbaum & Grehan sp. n. <p>Figs. 1 a–c, 4a, 5a, 6a, 7a, 8a, 9a, 12a</p> <p> <b>Etymology</b>. Named for the Meifeng Highland Experimental Station where the holotype was collected.</p> <p> <b>Holotype</b> ♂ with the following labels (separated by forward slashes): Central Taiwan; near Puli, Nantou Co.; Meifeng, ca. 2100 m NN; 24°05’19 N / 121°10’26 E; LF, 11 May 2011; leg. Mei-Yu Chen & U. Buchsbaum. Deposited in NMNS.</p> <p> <b>Diagnosis.</b> A medium sized <i>Endoclita</i> species with a darker shaded triangular region over much of the discal area and a trapezoid ‘recess’ in the central anterior discal cell. These features are also present in <i>E. chalybeatus</i> (Moore, 1879) (northeastern India), <i>E. davidi</i> (Taiwan and western China), <i>E. kosemponis</i> (Taiwan), <i>E. magnus</i> (Tindale, 1942) (southwestern India), <i>E. malabaricus</i> (Moore, 1879) (southwestern India), <i>E. signifer</i> (Walker, 1856) (northeastern India), and <i>E. sinensis</i> (Taiwan and eastern China), but absent from the Taiwanese species <i>E. atayala</i> and <i>E. inouei</i>. Within the triangular shaded discal cell species present in Taiwan, the FW of <i>E. meifenga</i> <b>sp. n.</b> can be distinguished from <i>E. kosemponis</i> and <i>E. sinensis</i> by the presence of a prominent costal lobe. The FW pattern of <i>E. meifenga</i> <b>sp. n.</b> is very similar to <i>E. davidi,</i> but there is a pale submarginal band extending across Rs2 and Rs3 that is absent in <i>E. davidi.</i> The male genitalia of <i>E. meifenga</i> <b>sp. n.</b> and <i>E. davidi</i> are also distinct, including a contrasting concave vs convex shaped posterior ventral margin of the pseudotegumen.</p> <p> <b>Description.</b> Male holotype (Fig. 1 a–c): Wingspan 71 mm; FW length: 33 mm, width: 14 mm, ratio 2.4: 1; HW length: 29 mm, width: 12, ratio 2.4: 1.</p> <p> <i>Head.</i> Eyes prominent. Antenna filiform, pale yellowish brown, scape cylindrical, pedicel rounded and slightly barrel shaped, flagellum with 22 segments and covered with numerous sensillae caeticae, lamellar scales absent, annuli slightly larger centrally, narrowing to apex. Interocular-antennal scales absent.</p> <p> <i>Thorax</i>. Dorsally covered with pale to dark olive green scales, scutum III dark yellowish brown, anteriorly free of scales, lateral and ventral thorax olive green; FW costal margin with shallow costal lobe anterior to the discal white spot, margin almost straight from base to costal lobe, and distally a shallow convex curve to apex; outer margin a shallow curve merging into posterior margin; venation ‘hepialine’ (sensu Dumbleton 1966), Sc1 extending into costal lobe (Fig. 4a). FW dorsal ground colour pale greyish brown covered with olive green markings edged in pale greenish white. Single largest olive green patch forming a triangular shape bounded anteriorly by R and posteriorly by CuA2 and extending distally just beyond the Cu-M-Rs cross veins; a greyish brown anterior trapezoid ‘recess’ patch in anterior discal cell anteriorly bounded by R (Fig. 12a). A premarginal band of olive green extends obliquely from CuA to the costal margin near the apex, comprising elliptical shapes between the veins, and darkest between costal margin and M 1. Adjacent submarginal band pale, extending to costal margin at apex with darker marginal band between apex and almost to Rs4 (Fig. 12a). An ovoid white spot edged basally with dark olive green is located on the basal side of the M 1 –M 2 cross vein. Costal region with 4–5 pale olive patches edged with pale greenish white and separated by pale grey. Ventral FW with costal pocket; pale grey to greyish green with dorsal ornamentation between costal margin and Sc; posteriorly oriented row of piliform scales along Sc; softer piliform scales across much of the basal and central wing surface. Dorsal HW grey with pale olive green scales over anterior apical region and marginal scales. Ventral HW pale grey to greyish green with dorsal ornamentation between costal margin and Sc. Legs pale greyish olive; leg length ratio pro: meso: meta 1:1.2:0.77; proleg lacking epiphysis; metatibia with yellowish to reddish brown androconia and large androconial gland along dorsal length of tibia (Fig. 5a).</p> <p> <i>Abdomen</i> (Fig. 6a, 7a, 8a) Pale greyish olive; tergites and sternites moderately sclerotized; tergum II with lateral ridge extending anterio-medially to lateral tuberculate plate, anterior ridge extending from tergosternal connection to dorsal median (Fig. 6a); tergosternal connection with broad, triangular central region, lacking tergal knob, lateral and dorsal brace almost at right angles, dorsal brace not fused to anterior ridge of TII (Fig. 7a); Segment II pleurum with lateral pouch, sternum II elongate and laterally concave, anterio-lateral arms subrectangular and obliquely angled, anterior margin forming broad ‘V’ shape (Fig. 6a, one lateral arm broken off); tergum VIII an isosceles trapezoid with lateral edges curving anteriorly and narrowing to posterior margin; sternum VIII sub-rectangular, slightly wider posteriorly, anterior and lateral margins straight, posterior margin with medial rectangular concavity (Fig. 8a).</p> <p> <i>Male genitalia</i> (Fig. 9a). Tegumen (intermediate plate) elongate. Saccus (vinculum) triangular, lateral edge almost straight, posterior margin with medial apical tooth and lateral, curved apodemal ridges. Tergal lobes not observed. Pseudotegumen well developed, margin adjacent to anogenital field with a ragged or broken edge with a triangular dorso-posterior projection, a blunt medial posterior projection angled to the median, and a strongly sclerotized ventral W-shaped bridge meeting across the median as an anterio-ventral nexus, and dorso-posterior margin fused across the median forming a narrow tubular junction. Fultura superior membranous, fultura and inferior sub-square with concave lateral edges. Valva small relative to pseudotegumen, narrow, digitiform, apex rounded. Phallus membranous, without cornutus.</p> <p> <b>DNA sequences:</b> The following sequences were obtained from the COI gene and were processed according to the BOLD System (boldsystems.org/). In the absence of comparable species in BOLD, only the available sequences are presented below.</p> <p>Female unknown.</p> <p> <b> <i>Endoclita meifenga</i> Buchsbaum & Grehan sp. n.</b> Sample ID: BC ZSM Lep 59526, Process ID: GWOTK290-12, BIN URI: BOLD: ABX1145</p> <p>Sample Nucleotide Sequence:</p> <p>AACTTTATATTTTATTTTTGGTATTTGAGCAGGAATAATTGGTACTTCATTAAGATTATTAATTCGAACAG AATTAGGAAACCCAGGATCTTTAATTGGAGATGATCAAATTTATAATGTAATTGTAACAGCACATGCTTT TATTATAATTTTTTTTATAGTTATACCAATTATAATTGGAGGATTTGGAAATTGATTAGTTCCATTAATATT AGGAGCACCAGATATAGCTTTCCCACGATTAAATAATATAAGATTCTGGCTATTACCCCCATCATTAATA TTATTAATTTCTAGAAGAATCGTTGAAAATGGAGCAGGAACAGGCTGAACTGTTTACCCCCCACTATCT GCAAATATTGCACATGCTGGAAGATCTGTTGATTTAGCAATTTTTTCTCTACATTTAGCAGGAATTTCTT CTATTTTAGGGGCAGTAAATTTTATTACAACTGTAATTAATATACGATCAGAAGGAATATCTTTTGATCG AATACCTTTATTTGTTTGAAGAGTAGCAATTACTGCTTTATTACTTTTATTATCATTACCTGTACTAGCAG GAGCTATTACTATATTATTAACAGATCGAAATTTAAATACTTCATTTTTTGATCCTGCGGGAGGAGGAGA TCCAATTTTATATCAACATTTATTT</p> <p>Amino Acid Sequence</p> <p>TLYFIFGIWAGMIGTSLSLLIRTELGNPGSLIGDDQIYNVIVTAHAFIMIFFMVMPIMIGGFGNWLVPLMLGA PDMAFPRLNNMSFWLLPPSLMLLISSSIVENGAGTGWTVYPPLSANIAHAGSSVDLAIFSLHLAGISSILGA VNFITTVINMRSEGMSFDRMPLFVWSVAITALLLLLSLPVLAGAITMLLTDRNLNTSFFDPAGGGDPILYQH LF</p> <p> <b>Distribution.</b> Known only from the type locality in northern Taiwan (Fig. 13 a–b). The Highland Experimental Farm (http://mf.shengchi.com.tw/enweb/) is an open area of agricultural crops and dry meadows at an elevation of about 2,100 m and surrounded by natural mountain forest. In the days preceding collecting, the weather was dry and warm followed by misty and cloudy conditions with light rain and an evening temperature of about 15°C on the day of collection (May, 11 th) which took place just a few days before a typhoon hit Taiwan (the principal typhoon season usually lasting from about June through October).</p>Published as part of <i>Buchsbaum, Ulf & Grehan, John R., 2019, New species of Endoclita (Lepidoptera: Hepialidae) and revived species status of E. kosemponis from Taiwan, pp. 432-444 in Zootaxa 4551 (4)</i> on pages 434-436, DOI: 10.11646/zootaxa.4551.4.3, <a href="http://zenodo.org/record/2623047">http://zenodo.org/record/2623047</a>
- …
