This paper is concerned with information structures used in rigid formations of autonomous agents that have leaderfollower architecture. The focus of this paper is on sensor/network topologies to secure control of rigidity. We extend our previous approach for formations with symmetric neighbor relations to include formations with leader-follower architecture. Necessary and sufficient conditions...

Formations of multi-agent systems, such as satellites and aircraft, require that individual agents satisfy their kinematic equations while constantly maintaining inter-agent constraints. In this paper, we develop a systematic framework for studying formations of multiagent systems. In particular, we consider undirected formations for centralized formations and directed formations for decentrali...

The Shiranish Formation is cropped out in several areas northern Iraq. A stratigraphic and facies study was conducted within the Duhok region to determine sedimentary environment. Three microfacies, reflecting various subenvironments different shelf parts of deep sea, have been identified Formation. Four depositional environments are identified: slope, toe shelf, deep-sea or cratonic basin. reg...

We present a decentralized, behavior-based approach to assembling and maintaining robot formations. Our approach dynamically grows formations from single robots into line segments and ultimately larger and more complex formations. Formation growth occurs by negotiation when robots are in close proximity. The approach has been validated using simulation as well as experiments with physical robot...

The present study represents a detailed systematic of obtained ostracods in sixty three samples from an outcrop section the Shiranish Formation (Campanian – Maastrichtian), Dukan area, Kurdistan, northern Iraq. Thirty ostracod species belonging to twenty one genera are found, whereas nineteen previously recorded. Eleven new described detected, which represented Bairdia dukanensis sp. nov., Bair...

The individual feathers in the skin of a developing chicken embryo are arranged in a precise array within a series of so-called 'tracts'. The images above show nascent feather buds in the legs of embryos at 8–9 days of incubation. Buds are added sequentially across the forming feather tract, as shown by the range of developmental stages in the image at top left. (In all three upper images, buds...

This paper treats the problem of the merging of formations, where the underlying model of a formation is graphical. We first analyze the rigidity and persistence of metaformations, which are formations obtained by connecting several rigid or persistent formations. Persistence is a generalization to directed graphs of the undirected notion of rigidity. In the context of moving autonomous agent f...

Multi-agent formations have been recently the subject of many studies. An important operational challenge, largely unaddressed in the literature, is to ensure that functionality of the formation is retained should agents be lost through misadventure, mission reassignment, and so on. In the context of sensor networks, it is also important to allow for the loss of multiple sensors as the low qual...

Marine transgressions or microbial precipitation: What was the controlling factor of continental margin iron formation deposition? Introduction Iron formations, which can be found around the world today, have great importance as sources of iron and manganese ore, clues about the evolution of life on Earth, and even hints at possible life on Mars (Weber et al., 2006). Precambrian iron formations...

On the basis of stratigraphic ranges reported calcareous nannfossils for several species, two sections Shiranish Formation from Hiran in Erbil Governorate and Smaqoli area Sulaimaniya Governorate, Northern Iraq, are analyzed. Four biozones visible examined region, grouped as follows oldest to youngest: Uniplanarius gothicus Interval zone; Tranolithus phacelosus Rienhardtites lives Micula murus ...