This paper studies structural aspects of lattice path matroids, a class of transversal matroids that is closed under taking minors and duals. Among the basic topics treated are direct sums, duals, minors, circuits, and connected flats. One of the main results is a characterization of lattice path matroids in terms of fundamental flats, which are special connected flats from which one can recove...

according to the iranian code of practice for seismic resistant design of buildings, soft storey phenomenon happens in a storey when the lateral stiffness of the storey is lower than 70% of the stiffness of the upper storey, or if it is lower than 80% of the average stiffness of the three upper stories. in the combined structural systems containing moment frames and shear walls, it is possible ...

We show that any lattice of finite length is isomorphic to the lattice of fully dependent flats of a rank-finite independence space, which is finite if the given lattice is finite. If a suitable submodular function is given on the lattice, the independence space may be so chosen that this submodular function corresponds to the rank function of the independence space under the constructed isomor...

Tidal flat, a transition zone between the ocean and land, forms a unique ecosystem, providing the habitat for various specious of fauna and flora, which is very important in purifying pollutants discharged from land and in providing marine products such as oysters and many kinds of shellfishes [1]. Thus, monitoring and mapping of tidal flat is urgently needed for sustainable managements and the...

Microtopography is a characteristic feature of many natural wetlands that is commonly lacking in restored wetlands (RWs). Consequently, it has been suggested that microtopography must be reestablished in RWs to accelerate the development of wetland function. The objective of this research was to examine responses of hydrology, soils, and vegetation to microtopographic reestablishment at a 3-yea...

[1] Fossil foraminifera are critical to paleoceanographic reconstructions including estimates of past episodes of methane venting. These reconstructions rely on benthic foraminifera incorporating and retaining unaltered the ambient isotopic compositions of pore fluids and bottom waters. Comparisons are made here of isotopic compositions of abundant live and fossil foraminifera (Uvigerina peregr...

Several authors have successfully created and employed vintage cohorts and housing typologies in research addressing energy renovation needs in the existing dwelling stock. This paper suggests that the idea of types would be useful in creating living quality related renovation and adaptation concepts for homes as well. Such concepts could be used for increasing accessibility and individuality o...

The aim of this paper is to discuss properties of fuzzy regular-flats, fuzzy Cflats, fuzzy alternative-sets and fuzzy i-flats. Moreover, we characterize some peculiar fuzzy matroids via these notions. Finally, we provide a decomposition of fuzzy strong maps.

It is shown that for fixed 1 ≤ r ≤ s < d and > 0, if X ⊂ PG(d, q) contains (1+ )qs points, then the number of r-flats spanned by X is at least c( )q(r+1)(s+1−r), i.e. a positive fraction of the number of r-flats in PG(s+ 1, q).