Probabilistic cellular automata with conserved quantities

We demonstrate that the concept of a conservation law can be naturally extended from deterministic to probabilistic cellular automata (PCA) rules. The local function for conservative PCA must satisfy conditions analogous to conservation conditions for deterministic cellular automata. Conservation condition for PCA can also be written in the form of a current conservation law. For deterministic nearest-neighbour CA the current can be computed exactly. Local structure approximation can partially predict the equilibrium current for non-deterministic cases. For linear segments of the fundamental diagram it actually produces exact results.Comment: 17 pages, 2 figure

On the Parity Problem in One-Dimensional Cellular Automata

We consider the parity problem in one-dimensional, binary, circular cellular automata: if the initial configuration contains an odd number of 1s, the lattice should converge to all 1s; otherwise, it should converge to all 0s. It is easy to see that the problem is ill-defined for even-sized lattices (which, by definition, would never be able to converge to 1). We then consider only odd lattices. We are interested in determining the minimal neighbourhood that allows the problem to be solvable for any initial configuration. On the one hand, we show that radius 2 is not sufficient, proving that there exists no radius 2 rule that can possibly solve the parity problem from arbitrary initial configurations. On the other hand, we design a radius 4 rule that converges correctly for any initial configuration and we formally prove its correctness. Whether or not there exists a radius 3 rule that solves the parity problem remains an open problem.Comment: In Proceedings AUTOMATA&JAC 2012, arXiv:1208.249

Observations of Radar Backscatter at Ku and C Bands in the Presence of Large Waves during the Surface Wave Dynamics Experiment

Ocean radar backscatter in the presence of large waves is investigated using data acquired with the Jet Propulsion Laboratory NUSCAT radar at Ku band for horizontal and vertical polarizations and the University of Massachusetts CSCAT radar at C band for vertical polarization during the Surface Wave Dynamics Experiment. Off-nadir backscatter data of ocean surfaces were obtained in the presence of large waves with significant wave height up to 5.6 m. In moderate-wind cases, effects of large waves are not detectable within the measurement uncertainty and no noticeable correlation between backscatter coefficients and wave height is found. Under high-wave light-wind conditions, backscatter is enhanced significantly at large incidence angles with a weaker effect at small incidence angles. Backscatter coefficients in the wind speed range under consideration are compared with SASS-2 (Ku band), CMOD3-H1 (C band), and Plant's model results which confirm the experimental observations. Variations of the friction velocity, which can give rise to the observed backscatter behaviors in the presence of large waves, are presented

Long and short paths in uniform random recursive dags

In a uniform random recursive k-dag, there is a root, 0, and each node in turn, from 1 to n, chooses k uniform random parents from among the nodes of smaller index. If S_n is the shortest path distance from node n to the root, then we determine the constant \sigma such that S_n/log(n) tends to \sigma in probability as n tends to infinity. We also show that max_{1 \le i \le n} S_i/log(n) tends to \sigma in probability.Comment: 16 page

Современные задачи группового управления движением автономных необитаемых подводных аппаратов

Блинцов, В. С. Современные задачи группового управления движением автономных необитаемых подводных аппаратов = Modern problems of group motion control of remotely operated underwater vehicles / В. С. Блинцов, Л. Т. Алоба, Доан Фук Тхы // Зб. наук. пр. НУК. – Миколаїв : НУК, 2016. – № 3 (465). – С. 83–91.Запропоновано класифікацію методів групового застосування автономних незаселених підводних апаратів. Сформульовано безліч прикладних науково-технічних завдань зі створення систем централізованого та децентралізованого управління групою підводних апаратів.A classification of methods for applying group autonomous underwater vehicle is offered. The classification covers the flat rectilinear and curvilinear motion of underwater vehicles, as well as their spatial motion group. The set of applied scientific and technical tasks for the development of systems of centralized and decentralized management of a group of underwater vehicles is formulated. It performs a common mission.Предложена классификация методов группового применения автономных необитаемых подводных аппаратов. Сформулировано множество прикладных научно-технических задач по созданию систем централизованного и децентрализованного управления группой подводных аппаратов

Coexistence of Chiari 2 malformation and moyamoya syndrome in a 17-year-old girl.

A 17-year-old female with Chiari 2 malformation developed cerebral infarction with angiographically typical bilateral moyamoya vessels manifesting as sudden onset of moderate left hemiparesis. Magnetic resonance imaging revealed multiple infarcts in the right frontal lobe, agenesis of the corpus callosum, upward herniation of the dorsal cerebellum, tectal beak of the midbrain, and downward herniation of the cerebellar vermis. Cerebral angiography demonstrated occlusion of the bilateral internal carotid arteries and basal moyamoya vessels. Single photon emission computed tomography showed significantly reduced regional cerebral blood flow in the right frontoparietal cortex. The cerebral vascular reactivity to acetazolamide was diminished in both cerebral hemispheres. She underwent superficial temporal artery-middle cerebral artery anastomosis combined with encephalo-myo-synangiosis on the right, and on the left 6 months later. Cerebral angiography performed 4 months after the second operation showed good patency of the bypasses and substantial collateral vessels in both cerebral hemispheres. This association may have happened by chance, and a common etiology is uncertain, but a currently undetermined genomic component might have contributed to the disease progression

Сучасні завдання групового управління рухом автономних незаселених підводних апаратів

A classification of methods for applying group autonomous underwater vehicle is offered. The classification covers the flat rectilinear and curvilinear motion of underwater vehicles, as well as their spatial motion group. The set of applied scientific and technical tasks for the development of systems of centralized and decentralized management of a group of underwater vehicles is formulated. It performs a common mission.Предложена классификация методов группового применения автономных необитаемых подводных аппаратов. Сформулировано множество прикладных научно-технических задач по созданию систем централизованного и децентрализованного управления группой подводных аппаратов.Запропоновано класифікацію методів групового застосування автономних незаселених підводних апаратів. Сформульовано безліч прикладних науково-технічних завдань зі створення систем централізованого та децентралізованого управління групою підводних апаратів