Моделирование колебаний полюса Земли с помощью нечеткой логики и функции Вейерштрасса

At present, the study of the Earth and its geometry is of great interest to researchers in various fields of science. A number of studies concerning the Earth motion relative to the center of mass have been carried out. Methods of theoretical and celestial mechanics and mathematical statistics are used to prove that in the main approximation the Earth motion relative to the center of mass - the oscillation of the pole - is the union of two circles with a slow trend of the average position corresponding to the annual and the Chandler components.The article analyses the existing mathematical model (MM) of the oscillation process of the Earth's pole relative to the center of mass. The relationships of the Earth's pole oscillations relative to the center of mass with time are described by solving the Euler — Liouville differential equations of the celestial mechanics. The unknown coefficients in the equations are found using the numerical least-squares method by processing the daily data from the International Earth Rotation Service (IERS). It was noted that the examined MM does not allow observational data of the IERS to describe adequately the process of oscillations of the Earth's pole for a long time interval (up to 10 years), the discrepancy reaches 20%.For the first time, a method for describing and predicting the coordinates of the Earth's pole with time has been proposed using the Takagi — Sugeno fuzzy logic method. The developed method was tested for adequacy with the discrepancy of 4% at most over the entire time interval. An approach is proposed to describe the change in the coordinates of the Earth's pole using the first seven terms of the Weierstrass function series. The proposed method has a relatively high discrepancy with the IERS data (from 5 to 50%), but it allows us to describe the process of oscillations of the Earth's pole, as well as the method based on the Takagi — Sugeno fuzzy logic method over a long time interval.В настоящее время исследование Земли и ее геометрии вызывает широкий интерес исследователей различных сфер науки. Проведен ряд исследований, посвященных исследованию движения Земли относительно центра масс. Методами теоретической и небесной механики и математической статистики доказано, что в главном приближении движение Земли относительно центра масс – колебания полюса – есть объединение двух окружностей с медленным трендом среднего положения, отвечающих годичной и чандлеровской компонентам.Проведен анализ существующей математической модели (ММ) процесса колебаний полюса Земли относительно центра масс. Зависимости колебаний полюса Земли относительно центра масс с течением времени описываются решением дифференциальных уравнений небесной механики Эйлера — Лиувилля. Неизвестные коэффициенты в уравнениях находятся с использованием численного метода наименьших квадратов посредством обработки ежесуточных данных, представленных международной службой вращения Земли (МСВЗ). Отмечено, что рассмотренная ММ не позволяет адекватно данным наблюдений МСВЗ описать процесс колебаний полюса Земли на длительном интервале времени (до 10 лет), расхождение достигает 20%.Впервые предложен метод описания и прогнозирования координат полюса Земли с течением времени с использованием метода нечеткой логики Такаги — Сугено. Разработанный метод проверен на адекватность, расхождение не превысило 4% на всем временном интервале. Предложен подход к описанию изменения координат полюса Земли с использованием семи первых членов ряда функции Вейерштрасса. Предложенный метод имеет относительно высокое расхождение с данными МСВЗ (от 5 до 50%), однако позволяет описать процесс колебаний полюса Земли, как и метод, в основу которого положен метод нечеткой логики Такаги — Сугено, на длительном интервале времени

Towards a multimedia knowledge-based agent with social competence and human interaction capabilities

We present work in progress on an intelligent embodied conversation agent in the basic care and healthcare domain. In contrast to most of the existing agents, the presented agent is aimed to have linguistic cultural, social and emotional competence needed to interact with elderly and migrants. It is composed of an ontology-based and reasoning-driven dialogue manager, multimodal communication analysis and generation modules and a search engine for the retrieval of multimedia background content from the web needed for conducting a conversation on a given topic.The presented work is funded by the European Commission under the contract number H2020-645012-RIA

From music to mathematics and backwards: introducing algebra, topology and category theory into computational musicology

International audienceDespite a long historical relationship between mathematics and music, the interest of mathematicians is a recent phenomenon. In contrast to statistical methods and signal-based approaches currently employed in MIR (Music Information Research), the research project described in this paper stresses the necessity of introducing a structural multidisciplinary approach into computational musicology making use of advanced mathematics. It is based on the interplay between three main mathematical disciplines: algebra, topology and category theory. It therefore opens promising perspectives on important prevailing challenges, such as the automatic classification of musical styles or the solution of open mathematical conjectures, asking for new collaborations between mathematicians, computer scientists, musicologists, and composers. Music can in fact occupy a strategic place in the development of mathematics since music-theoretical constructions can be used to solve open mathematical problems. The SMIR project also differs from traditional applications of mathematics to music in aiming to build bridges between different musical genres, ranging from contemporary art music to popular music, including rock, pop, jazz and chanson. Beyond its academic ambition, the project carries an important societal dimension stressing the cultural component of 'mathemusical' research, that naturally resonates with the underlying philosophy of the “Imagine Maths”conference series. The article describes for a general public some of the most promising interdisciplinary research lines of this project

Knowledge Boundary Spanning Mechanisms in a Shared Services Centre Context

This study focuses on the roles of knowledge boundary spanning mechanisms and intellectual capital (human, structural, and relational) in managing knowledge sharing in an IT-specialized shared services centre (IT-SSC) context. Although the literature stresses the growing utilization of the SSC as an outsourcing model, there is a lack of studies that examine the dynamic process of knowledge sharing across the organizational boundaries in this specific business model. Drawing on the literatures on SSC and on cross-boundary knowledge sharing we propose a conceptual framework based on four research propositions that were validated with primary and secondary data. The results suggest that IT-SSCs present high human capital, but encounter challenges developing relational and structural capitals. It also appears that IT-SSC management tends to prefer the utilization of boundary spanners and boundary objects instead of boundary discourses and boundary practices as mechanisms for efficient boundary spanning