Characteristics of silent countingin synchronized swimmers

This article describes the temporal characteristics of silent counting as used duringa competition by the Russian youth team of synchronized swimmers. Theathletes listened to the music that accompanied their performance at the competition.Diff erent indices of silent counting were defi ned, such as the beginningand cessation of diff erent periods of counting, counting frequency, the stabilityof the temporal structure of silent counting, the degree of synchronization of silentcounting at diff erent moments during the sports program. We studied therelationship of these characteristics of counting with expert estimates of the athletes’sense of tempo, coordination of movements, and choreographic abilities

Comparative Characteristics of Time Perspective of Professional Athletes and Drug Addicted People

AbstractThe present article analyses the comparative characteristics of time perspective of professional athletes and drug addicted people. Participants who are addicted to drugs and professional athletes pose significant difference in time perspective: in their perception of “Future”, “Negative Past” and Positive Past”. Characteristics of time perspective are dynamic and change in the context of meaning-life orientations and stressful events. Excessive concentration of participants on the past or on the future could be a predictor that contributes to dependent behavior. The necessity of individual profile consideration in psychological work with athletes and drug-addicted people was shown

Mixing and flameholding in supersonic combustor by electrical discharge

Compared to a basic scramjet design, operation of scramjet combustors using plasma assisted ignition and flameholding offers considerably more flexibility over the choice of its geometry, due to replacing mechanical flameholders with a highly effective electrically driven apparatus. The articlce presents the results of an experimental study of supersonic combustor operation enhanced by an electrical discharge. A novel scheme of plasma assisted mixing, ignition, and flameholding is demonstrated, which combines a wall fuel injector and a high-voltage electric discharge into a single module. The experimental combustor with the cross-section of 72 mm (width) ´ 60 mm (height) and length of 600 mm operates at a Mach number of M = 2, initial stagnation temperature of airflow of T0 = 290–300 K, and stagnation pressure of P0 = 1.3–2.0 Bar. The combustor is equipped with four plasma ignition modules, flush-mounted side-by-side on the plane wall of the combustion chamber. The combustion tests were performed using ethylene injection with a total mass flow rate of GC2H4 \u3c 10 g/s and discharge power in the range of Wpl = 3 – 24 kW. The scope of the experiments includes characterization of the discharge interacting with the main flow and fuel injection jet, parametric study of ignition and flame front dynamics, and comparison of this scheme to earlier tested configuration. This approach demonstrates a significant advantage in terms of flameholding limits. An operation mode with strong combustion oscillations was observed at high fuel injection flow rates. Methods of flame front stabilization based on plasma application are discussed. The technique studied in this study may have significant potential for high-speed combustion applications, including cold start/restart of scramjet engines and support of transition regime in dual-mode and off-design operation

Resolving Structural Vibration Issues On a Water Flood Pump

Case Stud

Principles of Manufacturing of DC On-Board Harness for a Spacecraft Based on 3D Technology

This article describes in detail principles of manufacturing of DC on-board harness for spacecraft based on a new 3D design technology. This technology puts together all activities of on-board harness production, starting from electrical design and up to the final product readiness. Based on the analysis performed we proposed: necessary software, methods of wires and connector contacts connection, applicable wires and connectors available in Russian and European markets, shielding and insulating materials, test methods. The article discusses benefits of lightweight supply buses technology implementation (as compared to bundle of wires), which are: mass reduction, electrical performances stability improvement, lesser capacity between supply lines, better interference immunity, better thermal performances

Синхронный электродвигатель для привода механизмов в химически агрессивной среде

В данной статье рассматриваются вопросы исследования синхронных машин дискового типа герметичного исполнения для использования в составе оборудования химической отрасли. Приведены результаты моделирования машины дискового типа с магнитосвязанными дисками и данные, полученные при экспериментальном исследовании электромагнитных потерь в герметизирующей перегородке макетного образца

Развитие взглядов на взаимосвязь произвольного движения и его мысленного образа

Introduction. Mental rehearsal of motor skill performance improves its coordination and effectiveness. However, mental image has been considered to be a hypothetical basis for voluntary movements even before its practical use begins. The present paper provides an original view on the current motor imagery understanding as a resolution of conflicts inherent to earlier concepts. The compatibility between historical and modern motor imagery theories is discussed. Thereby, revision of some of existing recommendations  concerning mental imagery use in sports is underpinned.  Theoretical Basis. Ideomotor theory was the first concept considering mental imagery as a basis for voluntary movements. T. Laycock and W. B. Carpenter described motor consequences of uncontrolled expression of a dominant idea. In the context of H. Herbart’s, R. H. Lotze’s, and E. Harless’ work, this phenomenon can be viewed more broadly in the light of systemic role of mental imagery in controlling movements. A number of instrumental studies of involuntary motor activity during movement imagination provided experimental confirmation of such phenomena and supported scientific interest in the  ideomotor theory when it was criticized by the behaviorism. In the modern period, to  resolve existing contradictions, M. Jeannerod has suggested considering the motor image as a conscious representation of neurophysiological processes underlying the corresponding movement, which is formed in the absence of inactivating afferent  response of effector organs. Results and Discussion. The modern understanding of the motor imagery focuses on its  equivalence to the actual movement in terms of the underlying central neurophysiologica processes and their functions, including formation of skills with the repetition of a corresponding movement. Following P. F. Lesgaft’s idea, an individual’s cognitive analysis of movements and understanding of its logical structure by means of mental  imagery play an important role in motor learning, especially in its initial stages. Herewith, research shows that cognitive and motor processes are closely intertwined.Введение. Широко известно, что проработка двигательного навыка посредством мысленного представления способствует повышению его скоординированности и результативности. Однако образ рассматривался как гипотетическая основа произвольного движения еще до начала своего практического применения. Статья впервые представляет текущее понимание образа движения как разрешения противоречий, присущих более ранним взглядам, и рассматривает совместимость последних с современной точкой зрения, чем обосновывает необходимость пересмотра некоторых существующих рекомендаций по применению мысленного образа в спорте. Теоретическое обоснование. Отправной точкой в рассмотрении мысленного образа как основы произвольного движения явилась идеомоторная теория. Моторным эффектам, описанным как неконтролируемое выражение доминирующей идеи, посвящены работы Т. Лэйкока и У. Б. Карпентера. Однако их видение как проявления системной роли образа в контроле движения пришло благодаря трудам И. Ф. Гербарта, Г. Р. Лотце и Э. Харлесса. Экспериментальное подтверждение подобных явлений было получено в ряде инструментальных исследований непроизвольной двигательной активности при ее мысленном представлении, которые поддержали научный интерес к идеомоторной теории в условиях ее критики со стороны бихевиоризма. Разрешение противоречий было предложено на современном этапе М. Джиннеродом, рассматривающим двигательный образ как осознанную репрезентацию лежащих в основе соответствующего движения нейрофизиологических процессов, которая формируется при отсутствии инактивирующей обратной связи от исполнительных органов. Результаты и их обсуждение. Современное понимание двигательного образа фокусируется на его эквивалентности фактическому движению с точки зрения реализующих его центральных нейрофизиологических процессов и присущих ему свойств, в т. ч. формирования навыка при повторении соответствующего движения. Важную роль в двигательном обучении, особенно на начальных этапах, которую подчеркивал еще П. Ф. Лесгафт, играют когнитивный анализ движения и познание его смысловой структуры с помощью образа. При этом, как показывают исследования, когнитивные и моторные процессы тесно переплетены между собой