Исследование влияния концентрации соли на результат измерения погонной емкости кабеля

Описан метод измерения погонной емкости электрического кабеля непосредственно в процессе производства. Осуществлен анализ влияния электропроводности воды на результаты измерения емкости кабеля

Моделирование кривой опорной поверхности линейной функцией в расчетах на жесткость

Предлагается модель кривой опорной поверхности в виде линейной функции. На базе этой модели аналитически определяются жесткость и фактическая площадь упругого и пластического контакта при наличии упрочения. Приводится численное сопоставление результатов с распространенной моделью в виде степенной функции

Changes in balance coordination and transfer to an unlearned balance task after slackline training: a self-organizing map analysis

How humans maintain balance and change postural control due to age, injury, immobility or training is one of the basic questions in motor control. One of the problems in understanding postural control is the large set of degrees of freedom in the human motor system. Therefore, a self-organizing map (SOM), a type of artificial neural network, was used in the present study to extract and visualize information about high-dimensional balance strategies before and after a 6-week slackline training intervention. Thirteen subjects performed a flamingo and slackline balance task before and after the training while full body kinematics were measured. Range of motion, velocity and frequency of the center of mass and joint angles from the pelvis, trunk and lower leg (45 variables) were calculated and subsequently analyzed with an SOM. Subjects increased their standing time significantly on the flamingo (average +2.93 s, Cohen’s d = 1.04) and slackline (+9.55 s, d = 3.28) tasks, but the effect size was more than three times larger in the slackline. The SOM analysis, followed by a k- means clustering and marginal homogeneity test, showed that the balance coordination pattern was significantly different between pre- and post-test for the slackline task only (χ2 = 82.247; p 0.001). The shift in balance coordination on the slackline could be characterized by an increase in range of motion and a decrease in velocity and frequency in nearly all degrees of freedom simultaneously. The observation of low transfer of coordination strategies to the flamingo task adds further evidence for the task-specificity principle of balance training, meaning that slackline training alone will be insufficient to increase postural control in other challenging situations

Вопросы выбора рабочего режима асинхронного двигателя с регулируемой частотой

Исследуются условия работы асинхронного двигателя при переменной частоте в режиме с оптимальными значениями к.п.д. и коэффициента мощности. На основании совместного анализа законов частотного регулирования, обеспечивающих наименьшие значения реактивной мощности и потерь, определена зона оптимальных величин абсолютных скольжений, соответствующая работе двигателя с высокими энергетическими показателями

Physiological Adaptions to Acute Hypoxia

When tissues are insufficiently supplied with oxygen, the environment is said to be hypoxic. Acute (exposures to) hypoxia can occur occupationally, within the scope of training and competitions or under pathological conditions. The increasing interest in acute exposure to altitude for training and research purposes makes it more important than ever to understand the physiological processes that occur under hypoxic conditions. Therefore, the scope of this chapter is to describe the main types of hypoxia on the oxygen cascade, to summarize the physiological consequences of acute hypoxia on the three main areas and to highlight the clinical consequences of acute hypoxia exposures for healthcare practitioners