Notes on a New Perimeter

On Airport Perimeter Security

On Minimal Perimeter Polyminoes

This paper explores proofs of the isoperimetric inequality for 4-connected shapes on the integer grid Z, and its geometric meaning. Pictorially, we discuss ways to place a maximal number unit square tiles on a chess board so that the shape they form has a minimal number of unit square neighbors. Previous works have shown that “digital spheres” have a minimum of neighbors for their area. We here...

Perimeter-Crossing Buses: a New Attack Surface for Embedded Systems

Any channel crossing the perimeter of a system provides an attack surface to the adversary. Standard network interfaces, such as TCP/IP stacks, constitute one such channel, and security researchers and exploit developers have invested much effort into exploring the attack surfaces and defenses there. However, channels such as USB have been overlooked, even though such code is at least as comple...

Vertical perimeter versus horizontal perimeter

Given k ∈ N, the k’th discrete Heisenberg group, denoted H Z , is the group generated by the elements a1, b1, . . . , ak, bk, c, subject to the commutator relations [a1, b1] = . . . = [ak, bk] = c, while all the other pairs of elements from this generating set are required to commute, i.e., for every distinct i, j ∈ {1, . . . , k} we have [ai, aj ] = [bi, bj ] = [ai, bj ] = [ai, c] = [bi, c] = ...

Annotated Checklist of Rotifers of Tehran Province, Iran, with Notes on New Records

Despite rapid growth of our knowledge on the phylum Rotifera, only few studies on Iranian rotifers have been carried out. In this paper, we present a checklist of rotifers from the province of Tehran in Iran. In total, 45 species of rotifers (class Eurotatoria) are reported. Most of the recorded species are cosmopolitan in distribution. Cephalodella ventripes, Dicranophorus forcipatus, D. luetk...