scholarly journals Crossings and nestings in set partitions of classical types

2010 ◽  
Vol DMTCS Proceedings vol. AN,... (Proceedings) ◽  
Author(s):  
Martin Rubey ◽  
Christian Stump

International audience In this extended abstract, we investigate bijections on various classes of set partitions of classical types that preserve openers and closers. On the one hand we present bijections for types $B$ and $C$ that interchange crossings and nestings, which generalize a construction by Kasraoui and Zeng for type $A$. On the other hand we generalize a bijection to type $B$ and $C$ that interchanges the cardinality of a maximal crossing with the cardinality of a maximal nesting, as given by Chen, Deng, Du, Stanley and Yan for type $A$. For type $D$, we were only able to construct a bijection between non-crossing and non-nesting set partitions. For all classical types we show that the set of openers and the set of closers determine a non-crossing or non-nesting set partition essentially uniquely. Dans ce résumé, nous étudions des bijections entre diverses classes de partitions d'ensemble de types classiques qui préservent les "openers'' et les "closers''. D'une part, nous présentons des bijections pour les types $B$ et $C$ qui échangent croisées et emboôtées, qui généralisent une construction de Kasraoui et Zeng pour le type $A$. D'autre part, nous généralisons une bijection pour le type $B$ et $C$ qui échange la cardinalité d'un croisement maximal avec la cardinalité d'un emboîtement maximal comme il a été fait par Chen, Deng, Du, Stanley et Yan pour le type $A$. Pour le type $D$, nous avons seulement construit une bijection entre les partitions non croisées et non emboîtées. Pour tout les types classiques, nous montrons que l'ensemble des "openers'' et l'ensemble des "closers'' déterminent une partition non croisées ou non emboîtées essentiellement de façon unique.

10.37236/392 ◽  
2010 ◽  
Vol 17 (1) ◽  
Author(s):  
Martin Rubey ◽  
Christian Stump

In this article, we investigate bijections on various classes of set partitions of classical types that preserve openers and closers. On the one hand we present bijections for types $B$ and $C$ that interchange crossings and nestings, which generalize a construction by Kasraoui and Zeng for type $A$. On the other hand we generalize a bijection to type $B$ and $C$ that interchanges the cardinality of a maximal crossing with the cardinality of a maximal nesting, as given by Chen, Deng, Du, Stanley and Yan for type $A$. For type $D$, we were only able to construct a bijection between non-crossing and non-nesting set partitions. For all classical types we show that the set of openers and the set of closers determine a non-crossing or non-nesting set partition essentially uniquely.


2016 ◽  
Vol 9 (2) ◽  
pp. 179-189
Author(s):  
Laurent Sagart (沙加爾) ◽  
William H. Baxter (白一平)

It is proposed that oc pharyngealized onset consonants—that is, ‘type-A’ onset consonants—arose out of Proto-Sino-Tibetan plain consonants followed by geminate vowels separated by a pharyngeal fricative. When the first copy of the geminate vowel fell, the initial consonants formed clusters with the pharyngeal fricative, evolving into the oc pharyngealized consonants we reconstruct. In the Kuki-Chin branch of Tibeto-Burman, the pharyngeal fricative fell, and long vowels resulted. This proposal supposes a statistical correlation between Kuki-Chin long vowels and oc type-A words on the one hand, and between Kuki-Chin short vowels and oc type-B words on the other, as originally proposed by S. Starostin. A significant statistic bearing on forty-three probable Chinese-Kuki-Chin cognates supports this correlation. Thus reconstructed, a precursor language of Proto-Sino-Tibetan was aligned with Proto-Austronesian and Proto-Austroasiatic in exhibiting a surface constraint against monomoraic free words: by that constraint, the vowel of an underlying monosyllable was realized as a geminate with an intervening parasitic consonant such as a glottal stop or a pharyngeal fricative, while the vowels of a disyllable remained nongeminate. After reduction of disyllables to monosyllables, this process resulted in a pharyngealized vs. nonpharyngealized consonant distinction in oc. 論文提出對上古漢語咽化聲母(即“A類聲母”)來源的一個假設,認為咽化聲母來源於原始漢藏語的無標記輔音,並且此無標記輔音後跟隨著由咽部擦音[ʕ]分割的雙胞元音(geminate vowels)。在雙胞元音的前半部分脫落後,輔音聲母跟咽部擦音形成了複輔音。新形成的複輔音最終演變為上古漢語的咽化聲母。而在藏緬語庫基-欽(Kuki-Chin)語支中,則是咽化擦音脫落,使雙胞元音變為長元音。本文解釋了漢語與庫基-欽語中一個統計學的顯著相關性:一方面,庫基-欽語含長元音的詞與上古漢語含A類聲母的詞呈顯著相關;另一方面,庫基-欽語含短元音的詞與上古漢語含B類聲母的詞呈顯著相關,正如斯塔羅金(S. Starostin)所說。據此構擬,我們提出原始漢藏語、原始南島語與原始南亞語中的一個共同限制(constraint):禁止在語流中出現單音拍(monomoraic)詞。在這一限制的作用下,單音節詞的單元音發生了雙胞化(germination),雙胞元音中間插入了喉塞音或咽部擦音之類的次聲輔音。而同時,雙音節詞的元音無變化。漢語經過雙音節詞的單音節化,就形成了無標記輔音與咽化輔音的音位對立。(This article is in English.)


Author(s):  
Yrjö Lauranto

This article examines object case marking in a Finnish verb structure called the Projected Directive Construction, e.g. Liisa pyysi Matti-a lähte-mä-än ‘Liisa asked Matti to leave’ (Liisa.NOMINATIVE asked Matti-PARTITIVE leave-INF-ILLATIVE). The PDC is divided into three subtypes. Type A includes verbs such as pyytää ‘to request’, which take a partitive object regardless of the outcome of the action. Verbs used in type B, such as määrätä ‘to order’, take an accusative object despite the result of the action. Type C comprises verbs such as suostutella ‘to persuade’ taking either a partitive or an accusative object, depending on the outcome of the semiotic causation expressed in the clause. The object case marking in the three subtypes reflects the two-faceted nature of the construction: on the one hand, it is a construction used for reporting of speech, on the other, it is a causative construction. It seems that boundedness – as it has traditionally been defined – does not suffice to describe the alternation of the object case in the PDC.Kokkuvõte. Yrjö Lauranto: Projitseeritud direktiivsed konstruktsioonid ja objekti käände markeerimine soome keeles. Artiklis käsitletakse objekti käänet soome keele projitseeritud direktiivses konstruktsioonis (PDK), nt Liisa pyysi Matti-a lähte-mä-än ‘Liisa palus Matit ära minna’. PDK võib jagada kolme alltüüpi. Tüüp A sisaldab verbe nagu pyytää ‘paluda’, mis nõuavad partitiivobjekti, sõltumata tegevuse tulemusest. Tüüp B verbid nagu määrätä ‘käskida’ nõuavad akusatiivobjekti, sõltumata tegevuse tulemuslikkusest. Tüüpi C kuuluvad verbid nagu suostutella ‘veenda’, mis võivad võtta nii partitiivse kui akusatiivse objekti, sõltuvalt lausega väljendatud semiootilise põhjustatuse tulemusest. Kolme alltüübi käändemarkeering peegeldab konstruktsiooni kahetist olemust: ühelt poolt kasutatakse konstruktsiooni kõne vahendamiseks, teiselt poolt on tegemist kausatiivse konstruktsiooniga. Seega ei piisa PDK objekti käändevahelduse selgitamiseks vaid piiritletuse mõistest.Võtmesõnad: objekti käände markeerimine; piiritletus; akusatiiv; partitiiv; kõne ja mõtete vahendamine; projitseerimine; kausatiivne konstruktsioon; soome keel


2012 ◽  
Vol DMTCS Proceedings vol. AR,... (Proceedings) ◽  
Author(s):  
Carolina Benedetti

International audience We provide a Hopf algebra structure on the supercharacter theory for the unipotent upper triangular group of type {D} over a finite field. Also, we make further comments with respect to types {B} and {C}. Type {A} was explored by M. Aguiar et. al (2010), thus this extended abstract is a contribution to understand combinatorially the supercharacter theory of the other classical Lie types. Dotamos con una estructura de álgebra de Hopf la teoría de supercaracteres del grupo de matrices unipotentes triangulares superiores de tipo{D} sobre un cuerpo finito. Ademas, discutimos brevemente los tipos {B} y {C}. El tipo A fue explorado por M. Aguiar et al (2010), por lo tanto este resumen extendido es una contribución para entender combinatoriamente la teoría de supercaracteres de los otros tipos de Lie clásicos. Nous construisons une structure d'algèbre de Hopf sur la thérie des supercharactères du groupe de matrices unipotentes triangulaires supéieures de type {D}. Nous donnons aussi quelques commentaires à l'égard des types {B} et {C} . Le type {A} a été explorée par M. Aguiar et al. (2010), donc ce résumé étendu est une contribution à la théorie combinatoire des supercharactères pour les autres types de Lie classiques. \par


2011 ◽  
Vol DMTCS Proceedings vol. AO,... (Proceedings) ◽  
Author(s):  
Drew Armstrong ◽  
Brendon Rhoades

International audience This paper is about two arrangements of hyperplanes. The first — the Shi arrangement — was introduced by Jian-Yi Shi to describe the Kazhdan-Lusztig cells in the affine Weyl group of type A. The second — the Ish arrangement — was recently defined by the first author who used the two arrangements together to give a new interpretation of the q,t-Catalan numbers of Garsia and Haiman. In the present paper we will define a mysterious "combinatorial symmetry'' between the two arrangements and show that this symmetry preserves a great deal of information. For example, the Shi and Ish arrangements share the same characteristic polynomial, the same numbers of regions, bounded regions, dominant regions, regions with c "ceilings'' and d "degrees of freedom'', etc. Moreover, all of these results hold in the greater generality of "deleted'' Shi and Ish arrangements corresponding to an arbitrary subgraph of the complete graph. Our proofs are based on nice combinatorial labellings of Shi and Ish regions and a new set partition-valued statistic on these regions. Cet article traite de deux arrangements d'hyperplans. Le premier — arrangement Shi — a été introduit par Jian-Yi Shi pour décrire les cellules de Kazhdan-Lusztig du groupe de Weyl affine de type A. Le deuxième — arrangement Ish — a été récemment défini par le premier auteur pour donner une nouvelle interprétation des nombres q,t-Catalan de Garsia et Haiman. Ici nous définissons une mystérieuse "symétrie combinatoire" entre les deux arrangements et nous montrons que cette symétrie conserve un grand nombre d'informations. Par exemple, les arrangements Shi et Ish ont le même polynôme caractéristique, le même nombre de régions, de régions bornées, de régions dominantes, de régions avec c "plafonds'' et d "degrés de liberté'', etc. En outre, ces résultats se généralisent aux arrangements Shi et Ish "deleted'' correspondant à un sous-graphe arbitraire du graphe complet. Nos preuves reposent sur des étiquetages combinatoires des régions Shi et Ish, et sur une nouvelle statistique associée.


1930 ◽  
Vol 30 (1) ◽  
pp. 40-54 ◽  
Author(s):  
G. S. Wilson

1. Analysis of a series of 135 strains of B. aertrycke indicates that at least four well-defined types may be recognised on the basis of morphology, colonial formation, virulence to mice, and to a less extent agglutination by salt, serum, and acids. These types comprise: (i) type A—the normal smooth virulent form; (ii) type B—a smooth form of low virulence; (iii) type C—a roughish, so-called ichthyotic, form of low virulence; (iv) type D—the really rough avirulent form. Between these well-defined types certain transitional forms may sometimes be recognised, the virulence of which is frequently of an order intermediate between that of the A type on the one hand, and the B, C, or D types on the other.2. Evidence is brought to show that if a virulent strain is sub-cultured daily, under conditions known to lead to a fall in virulence of the whole culture, a gradual replacement occurs of the virulent type A bacilli by the avirulent B, C or D types. So long as an adequate proportion, which is very small, of type A bacilli persists in the culture the virulence of the whole culture remains fairly high; but when all type A bacilli have been replaced by bacilli of the B, C or D types the virulence of the whole culture falls considerably.


2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii41-ii41
Author(s):  
Junjie Zhen ◽  
Lei Wen ◽  
Shaoqun Li ◽  
Mingyao Lai ◽  
Changguo Shan ◽  
...  

Abstract BACKGROUND According to EANO-ESMO clinical practice guidelines, the MRI findings of LM are divided into 4 types, namely linear enhancement (type A), nodular enhancement (type B), linear combined with nodular enhancement (type C), and sign of hydrocephalus (type D). METHODS The MRI features of brain and spinal cord in patients diagnosed with NSCLC-LM in Guangdong Sanjiu Brain Hospital from 2010 until 2019 were investigated, and then were classified into 4 types. The imaging features were analyzed. RESULTS A total of 80 patients were enrolled in the study. The median age of the patients was 53.5 years old, and the median time from the initial diagnosis to the confirmed diagnosis of LM was 11.6 months. The results of enhanced MRI examination of the brain in 79 cases showed that the number of cases with enhancements of type A, B, C and D were 50 (63.3%), 0, 26 (32.9%) and 3 (3.8%), respectively, and that LM with metastases to the brain parenchyma was found in 42 cases (53.2%). The results of enhanced MRI examination of spinal cord in 59 cases showed that there were only enhancements of type A and C in 40 cases (67.8%) and 3 cases (5.0%), and no enhancement sign in the other 16 cases (27.2%). CONCLUSION MRI examination of brain and spinal cord will improve the detection rate of LM. The MRI features of NSCLC-LM in real world are mainly characterized by the linear enhancements of brain and spinal cord, followed by linear combined with nodular enhancement. The enhancements of type B and type D are rare in clinic. Almost half of the patients have LM and metastases to the brain parenchyma. Therefore, the differentiation of tumor metastases is needed to be paid attention to for the early diagnosis and the formulation of reasonable treatment plans.


1984 ◽  
Vol 62 (1) ◽  
pp. 97-106 ◽  
Author(s):  
Jacqueline Kovoor

Although hersiliid spiders do not spin any webs, their silk glands, which belong to six types, are large and complex. Two groups of ampullate glands, one opening on the anterior spinnerets and the other on the median spinnerets, secrete two proteins each. About 180 pyriform glands are clearly bipartite. Over 200 type A aciniform glands opening on the median and posterior spinnerets are made up of three categories of secretory cells. Silk from these glands consists of two proteins (core and outer coat) joined together by an intermediary layer of acidic glycoprotein. All the 160 type B aciniform glands opening on the posterior spinnerets secrete a single protein. Fifty tubuliform glands opening on the median and posterior spinnerets produce two proteins, one of which is coloured. As in Urocteinae, long posterior spinnerets and large, numerous aciniform and tubuliform glands are correlated with swathing of prey and egg-cocoon construction. In Lycosidae and Agelenidae, the ampullate glands show the same number and distribution according to the spinnerets. However, anatomical and histochemical features of hersiliid aciniform and ampullate glands are close to those of some Araneoidea. Apart from peculiar characteristics, silk glands of Hersilia might represent an intermediate evolutionary stage towards Araneoidea.


2019 ◽  
Vol 36 (1) ◽  
pp. 25-50
Author(s):  
Haruo Kubozono

Abstract This paper examines the nature and behavior of secondary H(igh) tones in Koshikijima Japanese, a highly endangered dialect spoken on three small, remote islands in the south of Japan. This dialect generally has a mora-counting prosodic system with two distinctive accent types/classes (Type A and Type B), and displays two H tones, primary and secondary, in words of three or more moras: The primary H tone appears on the penultimate and final moras in Type A and Type B, respectively, whereas the secondary H tone occurs at the beginning of the word redundantly. Koshikijima Japanese displays regional variations with respect to the secondary H tone, particularly regarding its domain/position, its (in)dependence on the primary H tone, its interaction with the syllable, and its behavior in postlexical phonology. This paper examines how the secondary H tone behaves differently in three distinct accent systems of the dialect: (i) the system described by Takaji Kamimura eighty years ago, (ii) the one that is found quite extensively on the islands today, including Kamimura’s native village (Nakakoshiki) and Teuchi Village, and (iii) the system observed in Kuwanoura Village today. Comparing the three accent systems, this paper also proposes historical scenarios to account for the different behaviors of the secondary H tone across time and space.


2017 ◽  
Vol 17 (3) ◽  
pp. 39-56 ◽  
Author(s):  
Sérgio Roberto Andrade Dantas ◽  
Fulvio Vittorino ◽  
Kai Loh

Abstract Contact of facades with degradation agents and direct incidence of ultraviolet radiation on external coatings make them more opaque over time, affecting their colour and reflectance characteristics. This study evaluated the effect of adding different TiO2 contents to mortars applied in concrete substrates in order to verify the reflectance maintenance on surfaces after exposure over time. Mortar with different concentrations of TiO2 (1%, 5%, 10%) were produced in relation to the total dry premix, added as a powder and compared to unpainted mortar without TiO2 (type "A") and painted mortar without TiO2 (type "B"), both used as a reference for colour and reflectance. Exposed over 16 months to climate conditions in São Paulo, regarding the maintenance of reflectance and solar radiation, the results showed that type "B" (0%TiO2) painted mortar presented the best performance. Type "C" (1%TiO2) and type "D" (5%TiO2) unpainted mortar remained more stable. Type "A" (0%TiO2) and type "E" (10%TiO2) unpainted mortar showed greater differences according to the Just Noticeable Difference (JND) range caused by dirt pick up.


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