Closed‐loop one‐way‐travel‐time navigation using low‐grade odometry for autonomous underwater vehicles

© The Author(s), 2017. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Journal of FIeld Robotics 35 (2018): 421-434, doi:10.1002/rob.21746.This paper extends the progress of single beacon one‐way‐travel‐time (OWTT) range measurements for constraining XY position for autonomous underwater vehicles (AUV). Traditional navigation algorithms have used OWTT measurements to constrain an inertial navigation system aided by a Doppler Velocity Log (DVL). These methodologies limit AUV applications to where DVL bottom‐lock is available as well as the necessity for expensive strap‐down sensors, such as the DVL. Thus, deep water, mid‐water column research has mostly been left untouched, and vehicles that need expensive strap‐down sensors restrict the possibility of using multiple AUVs to explore a certain area. This work presents a solution for accurate navigation and localization using a vehicle's odometry determined by its dynamic model velocity and constrained by OWTT range measurements from a topside source beacon as well as other AUVs operating in proximity. We present a comparison of two navigation algorithms: an Extended Kalman Filter (EKF) and a Particle Filter(PF). Both of these algorithms also incorporate a water velocity bias estimator that further enhances the navigation accuracy and localization. Closed‐loop online field results on local waters as well as a real‐time implementation of two days field trials operating in Monterey Bay, California during the Keck Institute for Space Studies oceanographic research project prove the accuracy of this methodology with a root mean square error on the order of tens of meters compared to GPS position over a distance traveled of multiple kilometers.This work was supported in part through funding from the Weston Howland Jr. Postdoctoral Scholar Award (BCC), the U.S. Navy's Civilian Institution program via the MIT/WHOI Joint Program (JHK),W. M. Keck Institute for Space Studies, and theWoods Hole Oceanographic Institution

Digital Music Notation Data Model and Prototype Delivery System

The U.Va. Library requests $44,164 in outright funds from NEH to collaborate with the University of Paderborn in Detmold, Germany, in conducting two workshops, one to be held in summer 2009 and one in spring 2010, which will promote an international collaboration to create a music notation data model and prototype delivery system. We intend to engage a select group of international scholars and technologists with a broad range of expertise in discussing the features and functions required in a scholarly XML music notation model, critically evaluate the existing data models, discuss optimum solutions for achieving the desired features, and plan for future implementation of the solutions. Our long-term plans include applying for further grant funding to continue to develop this project after this basic collaboration is complete

Digital Music Notation Data Model and Prototype Delivery System

The UVa Library requests $161,175 in outright funds from NEH to collaborate with the University of Paderborn in Detmold, Germany, to produce a Music Encoding Initiative (MEI) demonstration project and to engage in dissemination efforts that will establish MEI as the predominant academic encoding standard for music notation. The demonstration project will include basic software for transforming material into MEI, a searchable archive of representative MEI-encoded data, and a prototype delivery system for items in the archive. This will allow the scholarly community to overcome the limitations of today's printed editions by extending the potential of digital editions, implementing new methodological techniques for music research, and facilitating collaboration between musicologists

Глобальная шахматная игра Америки

Статья посвящена анализу источников геополитических замыслов политиков против славянских народов центральной и Восточной Европы и, в частности, России. Раскрыты идеи англосаксонской геополитики по недопущению образования Стратегического Континентального Союза вокруг "географической оси истории". Изложена последовательная агрессивная политика США против СССР, Югославии, народов Ближнего Востока. Отмечена нависшая угроза глобализаторов Запада в отношении суверенных России и Украины.Стаття присвячена аналізу джерел геополітичних задумів політиків проти слов'янських народів центральної та Східної Європи та Росії. Розкрити ідеї англосаксонської геополітики з недопущення утворення Стратегічного Континентального Союзу навколо "географічної вісі історії". Викладена послідовна агресивна політика ЗША проти СССР, Югославії, народів ближнього Сходу. Відмічена найвища погроза глобалізаторів Заходу у відношенні суверенних Росії та України.This article is devoted to the analysis of the sources of the geopolitical designs of politicians against Slavonic people of the Central and Eastern Europe and particularly against Russia. The ideas of the Anglo-Saxon geopolitics against creation of the Strategic Continental Union around 'geographical axis of the history" are revealed. Gradual aggressive politics of the USA against USSR, Yugoslavia and Near East is stated. Overhung threat of the western globalizators related to the sovereign Russia and Ukraine

The system-biological GLOBE 3D Genome Platform.

Genomes are tremendous co-evolutionary holistic systems for molecular storage, processing and fabrication of information. Their system-biological complexity remains, however, still largely mysterious, despite immense sequencing achievements and huge advances in the understanding of the general sequential, three-dimensional and regulatory organization. Here, we present the GLOBE 3D Genome Platform a completely novel grid based virtual “paper” tool and in fact the first system-biological genome browser integrating the holistic complexity of genomes in a single easy comprehensible platform: Based on a detailed study of biophysical and IT requirements, every architectural level from sequence to morphology of one or several genomes can be approached in a real and in a symbolic representation simultaneously and navigated by continuous scale-free zooming within a unique three-dimensional OpenGL and grid driven environment. In principle an unlimited number of multi-dimensional data sets can be visualized, customized in terms of arrangement, shape, colour, and texture etc. as well as accessed and annotated individually or in groups using internal or external data bases/facilities. Any information can be searched and correlated by importing or calculating simple relations in real-time using grid resources. A general correlation and application platform for more complex correlative analysis and a front-end for system-biological simulations both using again the huge capabilities of grid infrastructures is currently under development. Hence, the GLOBE 3D Genome Platform is an example of a grid based approach towards a virtual desktop for genomic work combining the three fundamental distributed resources: i) visual data representation, ii) data access and management, and iii) data analysis and creation. Thus, the GLOBE 3D Genome Platform is the novel system-biology oriented information system urgently needed to access, present, annotate, and to simulate the holistic genome complexity in a unique gateway towards a real understanding, educative presentation and curative manipulation planning of this tremendous evolutionary information grail – genomes

Dynamical effects induced by long range activation in a nonequilibrium reaction-diffusion system

We both show experimentally and numerically that the time scales separation introduced by long range activation can induce oscillations and excitability in nonequilibrium reaction-diffusion systems that would otherwise only exhibit bistability. Namely, we show that the Chlorite-Tetrathionate reaction, where autocatalytic species diffuses faster than the substrates, the spatial bistability domain in the nonequilibrium phase diagram is extended with oscillatory and excitability domains. A simple model and a more realistic model qualitatively account for the observed behavior. The latter model provides quantitative agreement with the experiments.Comment: 19 pages + 9 figure

Информационные ресурсы Латвийской академической библиотеки: Проблемы создания и использования

Adolescents who attend special education for behavioural problems (SEB) and adolescents who live in a residential youth care institution (RYC) are characterised by behavioural disorders and problematic family backgrounds and have an increased risk for substance use. Though it is likely that the high rates of substance use in SEB/RYC settings might be inherent to the risk profile of these adolescents, little is known about the actual role the risk profile has in explaining substance use. The present study examined the extent to which the elevated risk of substance use in SEB/RYC can be explained by high levels of individual, family, and peer risk indicators that are known to characterise their risk profile. Self-report questionnaires from 531 adolescents in RYC (50 % male; mean age 14.7) and 603 adolescents in SEB (81 % male; mean age 14.1) were compared with information from 1,905 adolescents attending special education for students with learning disabilities (SEL) (56 % male; mean age 14.1). Results show that adolescents in SEB/RYC reported higher levels of daily smoking, weekly alcohol consumption, cannabis and hard drug use, as well as greater prevalence of individual, family and peer factors. Though individual, family and in particular peer risk indicators all explain some of the variance in substance use, the differences between adolescents in SEB/RYC compared with SEL remained significant and substantial, with the exception of heavy alcohol consumption. These findings suggest that deviant peer affiliation, in particular, plays a role in explaining high substance use levels in SEB/RYC and those factors relevant to the residential settings and special education schools might also contribute to substance use in these high-risk groups

Affinity, stoichiometry and cooperativity of heterochromatin protein 1 (HP1) binding to nucleosomal arrays

Heterochromatin protein 1 (HP1) participates in establishing and maintaining heterochromatin via its histone-modification-dependent chromatin interactions. In recent papers HP1 binding to nucleosomal arrays was measured in vitro and interpreted in terms of nearest-neighbour cooperative binding. This mode of chromatin interaction could lead to the spreading of HP1 along the nucleosome chain. Here, we reanalysed previous data by representing the nucleosome chain as a 1D binding lattice and showed how the experimental HP1 binding isotherms can be explained by a simpler model without cooperative interactions between neighboring HP1 dimers. Based on these calculations and spatial models of dinucleosomes and nucleosome chains, we propose that binding stoichiometry depends on the nucleosome repeat length (NRL) rather than protein interactions between HP1 dimers. According to our calculations, more open nucleosome arrays with long DNA linkers are characterized by a larger number of binding sites in comparison to chains with a short NRL. Furthermore, we demonstrate by Monte Carlo simulations that the NRL dependent folding of the nucleosome chain can induce allosteric changes of HP1 binding sites. Thus, HP1 chromatin interactions can be modulated by the change of binding stoichiometry and the type of binding to condensed (methylated) and non-condensed (unmethylated) nucleosome arrays in the absence of direct interactions between HP1 dimers

Turing Instability in a Boundary-fed System

The formation of localized structures in the chlorine dioxide-idodine-malonic acid (CDIMA) reaction-diffusion system is investigated numerically using a realistic model of this system. We analyze the one-dimensional patterns formed along the gradients imposed by boundary feeds, and study their linear stability to symmetry-breaking perturbations (Turing instability) in the plane transverse to these gradients. We establish that an often-invoked simple local linear analysis which neglects longitudinal diffusion is inappropriate for predicting the linear stability of these patterns. Using a fully nonuniform analysis, we investigate the structure of the patterns formed along the gradients and their stability to transverse Turing pattern formation as a function of the values of two control parameters: the malonic acid feed concentration and the size of the reactor in the dimension along the gradients. The results from this investigation are compared with existing experiments.Comment: 41 pages, 18 figures, to be published in Physical Review