73 research outputs found
Quantum dots desorption via high-power Nd:YAG laser pulses
In the present work, we investigated the mechanism behind the desorption of quantum dots (QDs) CdSe/ZnS (core/shell) aggregates via Q-switched Nd:YAG pulsed laser. After desorption, we trapped the aggregates in a linear quadrupole Paul trap and analyzed their dynamics using machine vision methods. We found that the number of desorbed aggregates is proportional to the laser radiation energy. The injection efficiency was 13.6% for all values of the laser pulse energy greater than 200 mJ. However, even thoughthe desorption process was also observed at lower values (<200 mJ), we did not register particles trapping in this case. This effect might be caused by the different nature of desorption at low powers (LIAD) and at high powers (desorption as a result of substrate ablation)
Spatial information recording procedure involving methods of close range photogrammetry as applied to archaeological researches
© SGEM2015. To date, the already existing traditional methods of archaeological field data classification and archiving do not meet modern requirements in the context of accuracy and convenience. The purpose of this study is to create and test more effective methods based on close range photogrammetry and GIS, which can be used to record all the stages of archaeological excavation process. Within the scope of the pilot project covering the territory of Bulgar ancient town (heritage asset), four methods of close range photogrammetry were used to depict all the excavation objects: 1) technique of central axis; 2) technique of perspective route photography shooting; 3) technique of fixed angles; 4) technique of suborthogonal photography shooting around perimeter. To reduce the cost of the survey, amateur cameras were used. Photogrammetric measurement results are: orthophoto, digital terrain model, threedimensional model covered with surface texture. These data eliminate the need of sketching excavation objects and performing leveling. Success depends only upon the correct choice of the positioning method. The method proposed in this paper is a finished tool which can be used by archaeologists. During the pilot test it became possible to minimize cartographic activities. Quality of the result obtained using photogrammetry and GIS was significantly higher in comparison to manual processing outcome
ENSURING ECONOMIC SECURITY OF RUSSIA IN THE CONTEXT OF AFRICAN DEVELOPMENT TRENDS: PROBLEMS AND PROSPECTS
Abstract
Purpose: A new scientific problem is posed and substantiated: the need to take into account the African economic development trends in the system of ensuring the economic security of Russia. In this context, in order to assess the security of the national economy and the competitive position of Russia, the results of scientific studies of the main development trends and threats in Africa, the position of various countries on the African continent are analyzed.
Methodology: The authors are based on the analysis of current scientific literature, government official documents, and statistical reports. The main methods of research are analytical review, comparison, systematic approach, cultural and civilizational approach.
Result: The article substantiates the position that taking into account the development trends of the African continent is an important component in the system of assessing the national economic security of Russia in the current period and in the future, ensuring competitiveness and strengthening the economic sovereignty of Russia, analyzing the potential of interaction with African countries in the management practice.
Applications: This research can be used for the universities, teachers and education students.
Novelty/Originality: The authors formulate the main directions of the activation of scientific research and concentration of practical efforts to improve the national economic security of Russia in the context of the development trend of the African continent
Enhancement effects of transition and Vavilov-Cherenkov radiation mechanisms under grazing interaction of fast electrons with a thick substrate applied by thin layer
The paper presents the results of a theoretical study and a mathematical model of radiation processes occurred during the grazing interaction of fast electrons with semi-infinite targets applied on a thin amorphous layer. The developed model considers Vavilov-Cherenkov and transition radiation mechanisms and predicts the possibility to enhance the angular radiation density under grazing incidence of fast electrons on the layer. The characteristics of possible extreme vacuum ultraviolet and soft X-ray sources are estimate
Enhancement Effects of Transition and Vavilov-Cherenkov Radiation Mechanisms Under Grazing Interaction of Fast Electrons With a Thick Substrate Applied by Thin Layer
The paper presents the results of a theoretical study and a mathematical model of radiation processes occurred during the grazing interaction of fast electrons with semi-infinite targets applied on a thin amorphous layer. The developed model considers Vavilov-Cherenkov and transition radiation mechanisms and predicts the possibility to enhance the angular radiation density under grazing incidence of fast electrons on the layer. The characteristics of possible extreme vacuum ultraviolet and soft X-ray sources are estimated
The development of radio and 3G based telemetry system for the remote gas accounting and control nodes
In this article we have described the use of vortex and recently developed ultrasonic flowmeters with high dynamic range of 1 to 1500 for industrial applications. Its software and the software of corresponding computing device is able to avoid gas leakage, to minimize energy consumption and to save human resources while maintaining metrological data. Described is the low power consumption that makes it possible to use this ultrasonic flowmeter in hard remote environment without direct management for a period of several month
САМОАДАПТИРУЕМОЕ ПРОГРАММНОЕ ОБЕСПЕЧЕНИЕ ДЛЯ АНАЛИЗА ИЗОБРАЖЕНИЙ
The method for development of intelligent software for image analysis is described. It is based on control shell of scripts generating that are controlled by an intelligent agent in software. The method is based on a combination of features of dynamic libraries and interpreter with a lot of functions for image processing.Описывается методика разработки интеллектуального программного обеспечения для анализа изображений путем формирования управляющих скриптов интерпретатора, которые генерируются интеллектуальным агентом в программном обеспечении
Метод снижения потерь при обнаружении динамического точечного объекта лазерной локационной системой с линейкой фотодетекторов
Laser detection and ranging is widely used to locate, measure speeds and detect the objects moving in the atmosphere and in space, as well as to ensure the safety of low-altitude aircrafts.A serious problem is to reduce time for finding and detection of a long-ranged object in the wide field angle, simultaneously decreasing the energy losses in the laser ranging system.So far, the hybrid on-board laser ranging systems have been developed. They use the “knife” type pattern of sounding radiation and multi-element photo-detectors. With using this technology, the viewing time of the search area does not exceed 30 s.The paper presents a method to reduce losses when a laser ranging system, based on the line of photo-detectors, detects a dynamic point object. Defocusing of the point object mage in the plane of the photo-detector device lies at the core of this method.The theoretical principles of radars, optics, and optoelectronics were used as the base to develop the method.Additionally, an algorithm for detecting the echo-signal received by two adjacent pixels to ensure the required detection characteristics when reducing the signal-to-noise ratio is proposed.When an image of the point object enters the “channel” between two pixels of a multi-element photo-detector, the maximum range measured by the laser ranging system is reduced, and the range measurement error increases.The point object image defocusing to 4π in combination with the proposed algorithm reduce the maximum measurement range of the laser ranging system to 21 ... 24%. The defocusing also enables us to reduce the increase in error of the measurement range to 1.9 times in the range of 500 ... 3000 m. Two types of photo-detectors, namely avalanche photodiodes and pin-photodiodes have been estimated.The practical implication consists in improving characteristics of laser ranging systems when dealing with dynamic point objects.The developed method can be used to create various laser ranging systems.Лазерная локация широко используется для определения координат, измерения скоростей и распознавания объектов, движущихся в атмосфере и в космическом пространстве, а также обеспечения безопасности маловысотных полетов летательных аппаратов.Серьезной проблемой является снижение длительности поиска и обнаружения объекта на больших дальностях в широком угловом поле с одновременным уменьшением энергетических потерь в лазерной локационной системе.К настоящему времени разработаны бортовые лазерные локационные системы гибридного типа, использующие «ножевую» диаграмму зондирующего излучения и многоэлементные фотоприемные устройства на базе линейки фотодетекторов. При использовании этой технологии длительность просмотра поля обзора не превышает 30 с.В данной работе представлен метод снижения потерь при обнаружении динамического точечного объекта лазерной локационной системой с линейкой фотодетекторов. Основой данного метода является дефокусировка изображения точечного объекта в плоскости фотоприемного устройства.В качестве базы для разработки метода использовались теоретические основы радиолокации, оптики, оптоэлектроники.Дополнительно предложен алгоритм обнаружения эхо-сигнала, принимаемого двумя соседними пикселями, который обеспечивает требуемые характеристики обнаружения при снижении отношения сигнал/шум.При попадании изображения точечного объекта в «канал» между двумя пикселями многоэлементного фотоприемного устройства снижается максимальная дальность измерений лазерной локационной системы, а также возрастает погрешность измерений дальности.Совместное использование дефокусировки изображения точечного объекта до значения 4π и предложенного алгоритма, уменьшает падение максимальной дальности измерений лазерной локационной системы до 21...24 %. Также дефокусировка позволяет снизить рост погрешности измерений дальности до 1,9 раз в диапазоне дальностей 500...3000 м. Оценки выполнены для двух типов фотодетекторов: лавинных фотодиодов и pin-фотодиодов.Практическая значимость состоит в улучшении характеристик лазерных локационных систем при работе по динамическим точечным объектам.Разработанный метод может быть использован при создании различных лазерных локационных систем
Итоги реализации положений GINA в практическое здравоохранение (6 лет работы Смоленска по антиастматической программе)
The results of six-year health-care system efforts in antiasthmatic program dedicated to the implementation of the principal guidelines of GINA were evaluated in Smolensk city. The educational programs for physicians and patients, and financial support of preferential release of antiasthmatic drugs have led to the radical changes in basic treatment of bronchial asthma. During the six-year period, the 23-fold increase in the proportion of inhalation glucocorticoids use has been accompanied by 1.7- and 1.5-fold decrease of the use of system steroids and cromoglycates, respectively. At the same period of time, in Smolensk the number of ambulance calls for asthmatic attack, the emergency hospitalization, the rate of disablement due to asthma, and primary disablement have been decreased 2.4, 2.3, 1.7, and 3.3 times, respectively.В Смоленске проведена оценка 6-летней работы здравоохранения по антиастматической программе, направленной на реализацию основных положений GINA. Образовательные программы для врачей и пациентов, финансовое обеспечение льготного отпуска антиастматических средств позволили координально изменить подход к базисной терапии больных астмой. Увеличение доли ингаляционных глюкокортикоидов сопровождалось снижением в 23 раза в структуре антиастматической терапии за 6 лет использования системных стероидов (в 1,7 раза), кромонов (в 1,5 раза). За этот период число вызовов скорой помощи к больным с приступом астмы уменьшилось в 2,4 раза, экстренная госпитализация в стационар сократилась в 2,3 раза, доля инвалидизирующей астмы в городе снизилась в 1,7 раза, а первичный выход на инвалидность – в 3,3 раза
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Serum Concentrations of Organochlorine Pesticides and Growth among Russian Boys
Background: Limited human data suggest an association of organochlorine pesticides (OCPs) with adverse effects on children’s growth
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