Neural network analysis of vibration signals in the diagnostics of pipelines

The article is devoted to the improvement of heat network calculation and diagnostics methods. Currently used instruments have many shortcomings for the diagnosis of pipelines, including low reliability of defect detection and subjective decision-making. The authors created an experimental stand, which allows to conduct the diagnostics of pipelines by a vibration-acoustic method. They studied steel pipes filled with water, the surface of which 50x50 mm defect and the depth of thinning of 2 mm, 3 mm, and 5 mm. Using the vibrationacoustic sensors fixed on an outer surface, the vibration signals generated by the water flow in the pipe were obtained. In order to process the large volumes of data obtained as the result of experiments, it is proposed to use artificial neural networks. Among all considered types of neural networks, the authors prefer Kohonen's networks due to the best effectiveness of a defect determination. The program for an acoustic signal processing and analyzing through a neural network was implemented in LabView 8.5 work environment. Depending on the accuracy of a problem being solved, and the details of a training sample, the program is able to produce the results of sample classification of samples for a defect-free and defective pipes of different depth of damage. The results of the classification by Kohonen's trained neural network show good abilities for the analysis of unknown samples and a high degree of their recognition reliability.Keywords: diagnosis, corrosion, defect, pipelines, acoustic signal, neural networ

The influence of changes in the project on the reliability of heat power systems during construction and installation works

However, during the construction and reconstruction of existing heat networks, cases that lead to unstable operation of newly laid or replaced areas arise. An important task is to minimize the reasons that can cause damage to replaced areas. Factors that negatively affect the reliability include: laying pipelines without design documentation, non-compliance of the regulatory requirements for their laying by installation organizations. The assumptions of design engineers developing the project and installers laying the heating main can lead to negative consequences, including a decrease in the reliability of the facilities functioning. Physical deterioration, coupled with the above factors, leads to a large number of failures of heat networks. Breakthroughs reduce the reliability of the entire heat supply system, worsen the quality of the supplied coolant and lead to an increase in the cost of maintenance of heat networks by operating organizations. The paper considers the influence of changes in the project during the construction and installation works on the reliability of the heat supply system. Document type: Articl

Pulse shaping system for INR proton linac

The system for proton beam pulse shaping in the 400 keV injection line of the INR linac is developed, built and implemented. The use of a traveling wave fast deflector and the Behlke Electronic fast HV transistor switch with operation voltage up to 6 kV enables formation and adjustment of different macro- and micro-pulses of the accelerated beam thus expanding considerably accelerator possibilities. It is important for many accelerator applications, especially for time-of-flight neutron studies.Реализована система формирования импульсов протонного пучка с энергией 400 кэВ на канале инжекции ускорителя ИЯИ РАН. Эта система с использованием быстрого дефлектора на бегущей волне и быстрого высоковольтного полупроводникового ключа фирмы Behlke Electronic с рабочим напряжением до 6 кВ существенно расширяет возможности ускорителя, так как обеспечивает регулирование частоты следования макроимпульсов, а также формирование различных микроимпульсов пучка. Реализация этих режимов необходима для проведения различных физических экспериментов, в том числе для времяпролетных исследований на нейтронных источниках.Реалізовано систему формування імпульсів протонного пучку з енергією 400 кеВ на каналі інжекції прискорювача ІЯД РАН. Ця система з використанням швидкого дефлектора на хвилі, що біжить, і швидкого високовольтного напівпровідникового ключа фірми Behlke Electronіc з робочою напругою до 6 кВ істотно розширює можливості прискорювача, тому що забезпечує регулювання частоти проходження макроімпульсів, а також формування різних мікроімпульсів пучка. Реалізація цих режимів необхідна для проведення різних фізичних експериментів, у тому числі для часопролітних досліджень на нейтронних джерелах

Adiabatic description of nonspherical quantum dot models

Within the effective mass approximation an adiabatic description of spheroidal and dumbbell quantum dot models in the regime of strong dimensional quantization is presented using the expansion of the wave function in appropriate sets of single-parameter basis functions. The comparison is given and the peculiarities are considered for spectral and optical characteristics of the models with axially symmetric confining potentials depending on their geometric size making use of the total sets of exact and adiabatic quantum numbers in appropriate analytic approximations

Chemical Department of Moscow University and the development of chemical education and scientific investigations in Russian University of People Friendship

The important contribution of Moscow University Chemical Department graduates to the chemical education and scientific investigations in Russian University of People Friendship is discussed in the article

Chemical Department of Moscow University and the development of chemical education and scientific investigations in Russian University of People Friendship

The important contribution of Moscow University Chemical Department graduates to the chemical education and scientific investigations in Russian University of People Friendship is discussed in the article

ОРГАНИЗАЦИЯ КОРРЕКТНОГО ЛЕЧЕНИЯ БОЛЬНЫХ С ПЕРЕЛОМАМИ ПРОКСИМАЛЬНОГО ОТДЕЛА БЕДРЕННОЙ КОСТИ

A retrospective analysis of the quality of specialized care provided to 820 patients with proximal femur fractures (PFF) at Solovyov Hospital (Yaroslavl) in 2013 was performed. A direct relationship was established between the time elapsed from the injury to hospital admission and the rate of vein thrombosis of the lower limbs. Operative activity in the treatment of patients with this pathology was 91.7%. A need for different implants for operative treatment of patients with this injury per 100,000 population was determined. Operative treatment of PFF in elderly and old-aged people should be considered a life-saving procedure to be performed on urgent indications(within 24 to 48 hours since the injury).Проведен ретроспективный анализ качества оказания специализированной помощи 820 больным с переломами проксимального отдела бедренной кости (ППБОК) в больнице им. Н.В. Соловьева (г. Ярославль) в 2013 г. Установлена прямая зависимость между сроком, прошедшим от травмы до госпитализации больных в стационар, и частотой развития тромбозов вен нижних конечностей. Отмечена высокая операционная активность (91,7%) в лечении пациентов. Определена потребность в различных имплантатах для оперативного лечения больных с указанными травмами при расчёте на 100 тысяч населения. Оперативное лечение ППОБК у лиц пожилого и старческого возраста следует рассматривать как жизнеспасающую процедуру и выполнять по срочным показаниям (в течение 24-48 часов с момента получения травмы)