A theoretical model of a wake of a body towed in a stratified fluid at large Reynolds and Froude numbers

International audienceThe objective of the present paper is to develop a theoretical model describing the evolution of a turbulent wake behind a towed sphere in a stably stratified fluid at large Froude and Reynolds numbers. The wake flow is considered as a quasi two-dimensional (2-D) turbulent jet flow whose dynamics is governed by the momentum transfer from the mean flow to a quasi-2-D sinuous mode growing due to hydrodynamic instability. The model employs a quasi-linear approximation to describe this momentum transfer. The model scaling coefficients are defined with the use of available experimental data, and the performance of the model is verified by comparison with the results of a direct numerical simulation of a 2-D turbulent jet flow. The model prediction for the temporal development of the wake axis mean velocity is found to be in good agreement with the experimental data obtained by Spedding (1997)

Dynamics of a small neutrally buoyant sphere in a fluid and targeting in Hamiltonian systems

We show that, even in the most favorable case, the motion of a small spherical tracer suspended in a fluid of the same density may differ from the corresponding motion of an ideal passive particle. We demonstrate furthermore how its dynamics may be applied to target trajectories in Hamiltonian systems.Comment: See home page http://lec.ugr.es/~julya

Цифровые технологии – база цифровой экономики топливозаправочных комплексов аэропортов гражданской авиации

The article analyzes the main information automated control systems for refueling complexes, based on this analysis, the problems of the airport ground handling functioning are identified, the main of which are the inefficiency of managing stochastic processes that occur in failure situations, as well as the lack of automated control systems for the level of purity of aviation fuel from mechanical impurities and water. The way to upgrade Groundstar Inform GmbH - a single integrated airport management system by increasing the capabilities of the system by adding new components is proposed. A solution to the problem of multi-resource planning of aircraft refueling in high-intensity flight conditions, including failure situations, based on intelligent simulation and resource management is proposed. As well as from the point of view of optimizing the solution of business process objectives the development of planning algorithms using the mathematical apparatus of fuzzy modeling and control, fuzzy sets and fuzzy logic underlying the intelligent modeling of processes is proposed. The concept of an adaptive information management system of technological processes of a refueling complex for monitoring the purity of jet fuel, based on dynamic on-line monitoring of the existence of mechanical impurities and water is introduced. The article examines the elements of creating a "Smart Refueling Complex", in which intelligent business processes are combined into one whole due to the use of "smart" operational processes and technological equipment. The introduction of digital technologies, "industry 4.0" tools and trends in automation, digitalization and digitalization of the modern aviation fuel supply for civil aviation is becoming the basis of the digital economy of civil aviation refueling complexes.В статье проведен анализ основных информационных автоматизированных систем управления топливозаправочных комплексов (далее ТЗК), на основе которого выявлены проблемы функционирования наземного обслуживания аэропорта, главные из которых — неэффективность управления стохастическими процессами, которые появляются в условиях сбойных ситуаций, а также отсутствие автоматизированных систем управления уровнем чистоты авиатоплива от механических примесей и воды. Предложен путь расширения (англ. upgrade) Groundstar Inform GmbH – единой комплексной системы управления аэропортом посредством увеличения возможностей системы за счет добавления новых компонентов. Представлено решение задачи мультиресурсного планирования заправок воздушных судов (далее ВС) в условиях высокой интенсивности полетов, в том числе и в условиях сбойных ситуаций, на основе интеллектуального имитационного моделирования и управления ресурсами, а также с точки зрения оптимизации решения задач бизнеспроцесса. Порекомендована разработка алгоритмов планирования с использованием математического аппарата нечеткого моделирования и управления, нечетких множеств и нечеткой логики, лежащих в основе интеллектуального моделирования процессов. Задана концепция адаптивной информационно-управляющей системы технологических процессов ТЗК для контроля чистоты авиатоплива на основе динамического on-line (онлайн) мониторинга наличия механических примесей и воды в авиатопливе. В статье рассматриваются элементы создания «Умного ТЗК», в котором интеллектуальные бизнес-процессы соединяются в одно целое благодаря использованию «умных» операционных процессов и технологического оборудования. Внедрение цифровых технологий, инструментов «индустрии 4.0» и тенденции автоматизации, цифровизации, диджитализации современного авиатопливообеспечения ВС ГА становятся базой цифровой экономики топливозаправочных комплексов ГА

Strangeness production in proton-proton and proton-nucleus collisions

In these lectures we discuss the investigation of the strange meson production in proton-proton ($pp$) and in proton-nucleus ($pA$) reactions within an effective Lagrangian model. The kaon production proceeds mainly via the excitations of $N^*$(1650), $N^*$(1710), and $N^*$(1720) resonant intermediate nucleonic states, in the collision of two initial state nucleons. Therefore, the strangeness production is expected to provide information about the resonances lying at higher excitation energies. For beam energies very close to the kaon production threshold the hyperon-proton final state interaction effects are quite important. Thus, these studies provide a check on the models of hyperon-nucleon interactions. The in-medium production of kaons show strong sensitivity to the self energies of the intermediate mesons.Comment: 16 pages, 9 figures, Talk presented in the workshop on Hadron Physics, Puri, India, March 7-17,200

Современное представление о химиоиндуцированной полинейропатии (обзор литературы)

This review focuses on сhemotherapy-induced polyneuropathy, which is a fairly common side effect and affects not only the quality of life of patients with malignancies, but can also lead to a change in patient management tactics, namely dose modification, delay of drug administration to complete cessation of treatment, which threatens the life of the patient. сhemotherapy-induced polyneuropathy is based on different mechanisms of damaging effects depending on the type of cytotoxic agent. The most neurotoxic drugs are platinum drugs, taxanes, periwinkle alkaloids, bortezomib, and thalido‑ mide. As a result of neurotoxic effects, damage occurs to thin and thick fibers of peripheral nerves. However, it is still a mystery why one patient develops manifestations of neurotoxicity and another does not. Therefore, the modern medical community is faced with the urgent question of further study of the mechanisms of development, risk factors, as well as the search for biomarkers and the development of prevention and treatment of сhemotherapy-induced polyneuropathy. The results of studies on the mechanism of onset, clinic, diagnosis, prevention and treatment of сhemotherapy-induced polyneu‑ ropathies are summarized. Обзор посвящен химиоиндуцированной полинейропатии – частому нежелательному явлению терапии злокачест‑ венных новообразований, которое снижает качество жизни пациентов и может приводить к изменению тактики ведения: модификации дозы, отсрочке введения препарата и даже полному прекращению лечения, что ставит под угрозу жизнь пациента. В основе химиоиндуцированного повреждающего действия периферических нервов лежат разные механизмы в зависимости от вида цитотоксического агента. Наиболее нейротоксичными являются препараты платины, таксаны, алкалоиды барвинка, бортезомиб и талидомид. В результате нейротоксического воздей‑ ствия возникает повреждение тонких и толстых волокон периферических нервов. Однако до сих пор остается загад‑ кой, почему у одного пациента развиваются проявления нейротоксичности, а у другого – нет. Перед современным медицинским сообществом по-прежнему остро стоит вопрос изучения механизмов развития, факторов риска, а также поиска биомаркеров и разработки методов профилактики, лечения химиоиндуцированной полинейропатии. Обобщены результаты исследований по механизму возникновения, клинике, диагностике, профилактике и лечению химиоиндуцированных полинейропатий.

News from the Muon (g-2) Experiment at BNL

The magnetic moment anomaly a_mu = (g_mu - 2) / 2 of the positive muon has been measured at the Brookhaven Alternating Gradient Synchrotron with an uncertainty of 0.7 ppm. The new result, based on data taken in 2000, agrees well with previous measurements. Standard Model evaluations currently differ from the experimental result by 1.6 to 3.0 standard deviations.Comment: Talk presented at RADCOR - Loops and Legs 2002, Kloster Banz, Germany, September 8-13 2002, to be published in Nuclear Physics B (Proc. Suppl.); 5 pages, 3 figure

Measurement of the Negative Muon Anomalous Magnetic Moment to 0.7 ppm

The anomalous magnetic moment of the negative muon has been measured to a precision of 0.7 parts per million (ppm) at the Brookhaven Alternating Gradient Synchrotron. This result is based on data collected in 2001, and is over an order of magnitude more precise than the previous measurement of the negative muon. The result a_mu= 11 659 214(8)(3) \times 10^{-10} (0.7 ppm), where the first uncertainty is statistical and the second is sytematic, is consistend with previous measurements of the anomaly for the positive and negative muon. The average for the muon anomaly a_{mu}(exp) = 11 659 208(6) \times 10^{-10} (0.5ppm).Comment: 4 pages, 4 figures, submitted to Physical Review Letters, revised to reflect referee comments. Text further revised to reflect additional referee comments and a corrected Fig. 3 replaces the older versio