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We give an exhaustive list of the residually connected, flag-transitive geometries of the alternating group A 8 satisfying the (IP)2 and RWPRI properties. The list was obtained with the aid of a computer and the software package MAGMA[1]. The programs used are based on the algorithms described in [15] and [16]. Many geometries were predicted by a theory of inductively minimal geometries. For the remaining geometries, we give an explicit construction proving their existence. These constructions rely on various geometrical objects resulting from the well-known isomorphisms A 8 ≌ PSL(4, 2) ≌ PO; +(6, 2).

We study the properties (2T )1 ,( IP)2, PRI, RPRI, QPRI and RWPRI for inductively minimal pairs ( ;G) consisting of a nite geometry and a group acting ag-transitively on it. For each of these properties, we characterize which inductively minimal pairs satisfy it.

The IFMIF/EVEDA project under the Broader Approach Agreement between Japan and EU aims at allowing a rapid construction phase of IFMIF in due time. The three main facilities, (1) the Accelerator Facility, (2) the Target Facility and (3) the Test Facility, are the subject of validation activities that include the construction of either full scale prototypes or smartly devised scaled down facilities that will allow a straightforward extrapolation to IFMIF needs. The installation of a Linac of 1.125 MW (125 mA and 9 MeV) of deuterons started in March 2013 in Rokkasho. The world largest liquid Li test loop is running in Oarai with an ambitious experimental programme for the years ahead. A full scale high flux test module that will house sim 1000 small specimens developed jointly in Europe and Japan has been constructed in Germany together with its He gas loop. A full scale medium flux test module to carry out on-line creep measurement has been constructed in Switzerland., 著者所属: 日本原子力研究開発機構(JAEA)

Julius Whiston showed that the size of an independent generating set in the symmetric group S n is at most n −1. We determine all sets meeting this bound. We also give some general remarks on the maximum size of an independent generating set of a group and its relationship to coset geometries for the group. In particular, we determine all coset geometries of maximum rank for the symmetric group S n for n >6.

Papiervouwen is weer een hipe. De verbanden met de wiskunde zijn steeds talrijker en er verschijnen steeds meer boeken die dit illustreren. Wij bespreken hier enkele boeken die de wiskundige als hedendaagse refernties mag beschouwen.

Cursusnota's voor Complexe Analyse

De re\"ele getallen kunnen we op verschillende manieren onderverdelen in twee complementaire delen. Wij geven hier drie manieren. We kunnen de re\"ele getallen opdelen in rationale en itrrationale getallen, in algebra\"{\i}sche en transcendente getallen en in normale en niet-normale getallen. Deze concepten ontstonden op verschillende tijdstippen in de geschiedenis van de wiskunde maar hun ontwikkeling toont veel gelijkenissen. Deze worden in dit artikel benadrukt en er worden ook enkele `open problemen' vermeld. Zo wordt duidelijk dat er nog veel te doen is binnen dit onderwerp.

Inductively minimal geometries form an infinite family of incidence geometries on which finite symmetric groups act flag-transitively. They were introduced in Buekenhout et al. (in: N.L. Johnson (Ed.), Mostly Finite Geometries, Marcel Dekker, New York, 1997, pp. 185–190) and satisfy, among other, the (IP)2 and RWPRI conditions (see Bull. Belg. Math. Soc. Simon Stevin 5 (1998) 213–219). In the present paper we characterize the truncations of inductively minimal geometries which satisfy both of these conditions. We also determine all rank 2 residues in these truncations. This enables one to find the diagram of these truncations.

Deze loep is een wandeling door de geschiedenis. We starten bij de Oude Grieken waar irrationale getallen zorgden voor heelwat opschudding en een sterfgeval. Leonhard Euler definieerde transcendente getallen maar stierf zonder er ooit een te zien. Zullen wij nog leven wanneer het eerste normaal getal ontdekt wordt?

In one of his papers [2], A. Neumaier constructed a rank 4 incidence geometry on which the alternating group of degree 8 acts flag-transitively. This geometry is quite important since its point residue is the famous A7-geometry which is known to be the only flag-transitive locally classical C3-geometry which is not a polar space (see [1]). By counting chambers, we prove that the A8-geometry has 70 planes. This can be found in a paper of Pasini's [4] without proof, but Neumaier's original paper only mentions 35 planes.

We prove that, up to isomorphism, for a given positive integer n, there is only one inductively minimal pair (Γ,Sym(n)) of rank n-1 that satisfies the intersection property. Moreover, we show that the diagram of Γ is linear.

In this paper we analyze from the technical point of view the possibility of developing the IFMIF facility (International Fusion Materials Irradiation Facility) in a stepped approach from the proto...