Variation of Physical and Mechanical Properties of Pinus Sylvestris L. Wood in the Boreal Zone of the European Northeast

The study considers variational aspects of physical and mechanical properties of Scots pine (Pinus sylvestris L.) wood depending on conditions and growth areas in the boreal zone of the European Northeast. Anatomical traits of xylem and its strength properties were analyzed. Based on the data received, statistical processing of the material was carried out using correlation and multivariate analysis. The impact of hazardous air emissions on variation of linear dimensions in structural elements of the annual height increment in the trunk diameter was estimated. A varying nature of the influence of environmental factors on the formation of strength properties of P. sylvestris wood in growth areas was attested. The variation value of basic wood density decreases as soil and hydrological conditions of growth improve. A significant negative correlation between basic wood density and distance to sources of hazardous air emissions in the areas of concentration of industrial enterprises was established. The results of multivariate analysis make it possible to reveal the weight of the influence of environmental factors and biometric characteristics of wood on volumetric and strength properties of pine wood. Growth in the impact zone of air emissions from large industrial enterprises in the study area does not produce a significant effect on the dynamics of wood strength properties, taking into account various growth conditions. For Scots pine growing in the European Northeast, the study determined a significant impact of the size and structure of the annual height increment of the trunk in terms of diameter, as well as the position of the wood sample in terms of trunk volume, on strength properties of pine wood

Physical Nature of the Processes in Structure Forming, Phase and Chemical Composition of pipe Permanent Joints when MMA Welding

The paper outlines peculiarities of structure formation, phase and chemical composition in regard to heat content in molten electrode metal beads when pipe steel (steel 09G2S) welding using power sources with various energy characteristics. Mathematical calculations indicate an inverter power source provides minor heat content into the bead of electrode metal when welding. Experimental research has pointed at 4-9 % increase in impact strength of joints produced using an inverter power source in comparison with samples produced applying a diode rectifier. The following factors can possibly give rise to the increasing impact strength: difference in microstructures of weld joints, up to 50% shortening ferritic plates in metal of weld joint, change in dimensions of ferritic grains in the heat-affected zone by as much as 17.5 %, and decrease in the extent of heat-affected zone by 50%

Optical device for determining the viability of biological tissue

The article solves the problem of increasing the objectivity of visual analysis of internal organs during surgery. The authors found that the spectral characteristics in the visible reflection spectrum allow the practicing surgeon to determine the presence of pathologies of the internal organs, as well as the location of their borders. The paper considers the existing methods for assessing the viability of biological tissues, the most promising one is selected. A description of the proposed device that implements the proposed method and a description of the program executed in the LabView environment is given. The work also presents a methodology for determining the optical parameters of the studied biological tissue of a group of conditionally healthy people, conducted statistical processing of data obtained experimentally and determined normal values

Export of Russian grain: prospects and the role of the state in its development

The article discusses the problems and issues of further development of Russian grain exports. The main export grain crop for Russia is wheat; the volume of wheat supplies to the world market exceeds 35 million tons. The study provides a list of the main geographical areas importing Russian wheat and analyzes the dynamics of changes in its supply. However, the export orientation for wheat leads to imbalances in the structure of production and regional distribution of grain crops in Russia. Grain is of fundamentally high importance for solving the problem of import substitution for the production of meat and dairy products and ensuring food security for the population of Russia; therefore, the study emphasizes the need for state management of the grain balance. In the long term, the regulation of grain exports should be reduced mainly to a system of economic measures, but at the moment, government participation is necessary as a driver in the development of production and logistics infrastructure. The complex of economic and political factors determines the diversification of wheat supplies from Russia due to the Far Eastern direction

Increasing Strength and Operational Reliability of Fixed Joints of Tubes by ММА Welding

This paper presents peculiar properties of structure formation, phase and chemical composition while welding of low-alloy steel 09MnSi2-1 depending on the dynamic characteristics of power sources of different types. Proper selection of power sources enables to decrease burning of alloy elements in metal of weld (Mn by 14% and Si by 17% of the weight ratio), to obtain more homogenous structure of deposited metal, to reduce length of heat-affected zone by 50% and to improve impact strength by 4-9%

Physical Nature of the Processes in Forming Structures, Phase and Chemical Compositions of Medium-Carbon Steel Welds

This work presents peculiarities of forming a structure, phase and chemical composition while welding medium-carbon steels (Steel 45) depending on a heat content of molten electrode metal droplets when using welding power sources having different power parameters. It was experimentally established that the power inverter provides the decreased heat input into droplets of electrode metal during the welding process. This stimulates obtaining a fine-grained structure of the deposited metal and heat affected zone, reduces the extent of the HAZ that enhances working properties of welded joints

Задание множества диагностических параметров системы на основе теории функциональных пространств

Развивается методический и математический аппарат формирования множества диагностических параметров сложных технических систем, содержание которого заключается в обработке траекторий выходных процессов системы с привлечением теории функциональных пространств. Траектории выходных переменных рассматриваются как измеримые по Лебегу функции. Это обеспечивает единство подхода к получению диагностических параметров вне зависимости от физической природы данных переменных и множества их скачкообразных изменений (конечных разрывов траекторий). Тем самым адекватно учитывается сложность построения, разнообразие физических принципов и алгоритмов функционирования систем. На множествах траекторий задается структура фактор-пространств измеримых функций, квадратично интегрируемых по Лебегу (пространства ). Свойства данных пространств позволяют раскладывать траектории по счетному множеству взаимно ортогональных направлений и представлять их в виде сходящегося ряда. Обоснован выбор множества диагностических параметров как упорядоченной последовательности коэффициентов разложения траекторий в частичные суммы рядов Фурье. Изложена усовершенствованная по сравнению с начальными вариантами процедура формирования множества диагностических параметров системы при разложении траектории в частичную сумму ряда Фурье по ортонормированному базису Лежандра. Предложен способ численного определения мощности такого множества. Раскрываются новые аспекты получения диагностической информации из вибрационных процессов системы. На множествах вибротраекторий задается структура пространств непрерывных функций, квадратично интегрируемых по Риману (пространства ). Поскольку они являются подпространствами в упомянутых выше фактор-пространствах , общеметодологические основы преобразования вибротраекторий остаются неизменными. Однако алгоритмическая составляющая выбора диагностических параметров становится более конкретной и обозримой. Это показано посредством реализации численной процедуры разложения вибротраекторий по ортогональному тригонометрическому базису, который содержится в пространствах  . Приводится обработка результатов экспериментальных исследований вибрационного процесса и задание на данной основе подмножества диагностических параметров в одной из контрольных точек системы. Материалы статьи представляют собой вклад в теорию получения информации о техническом состоянии сложных систем. Прикладное значение предложенных разработок — возможность их применения для синтеза алгоритмического обеспечения автоматизированных средств диагностирования

Ergatic management system as a factor in increasing the company's competitiveness

This article examined the relationship ergatic management systems and technical means of production in order to improve competitiveness. Ergatic management system - a system that includes as elements both the technical systems themes, and people interacting with these systems. For the effective functioning of such systems should be chosen rational ways people interact with technology based on the findings ergonomics

Manuscrit trouvé à Saint-Pétersbourg : Chronicon terræ prussiæ de Pierre de Duisbourg, traduit par Jean Potocki

Le manuscrit Aux Archives de l’Institut d’histoire de Saint-Pétersbourg est conservé un manuscrit imperceptible en apparence. Sa demi-reliure est typique pour la fin du XVIIIe ou début du xixe siècle : le dos et les coins sont confectionnés en cuir clair et les plats sont couverts en papier teinté de rose. Le manuscrit est écrit sur papier filigrané de deux sortes « Pro Patria » et « C&I Honig ». La dimension des feuillets est 20 cm x 31 cm. Aujourd’hui, le manuscrit consiste de 35 feuillets,..

Sovremennoe sostoyaniei perspektivy razvitiya oftal'mokhirurgiipri endokrinnykh narusheniyakh

Офтальмологи находятся на переднем рубеже борьбы с различными глазными заболеваниями у пациентов с эндокринными нарушениями, а риск возможных осложнений не должен препятствовать использованию всего арсенала имеющихся средств для адекватной зрительной и социальной реабилитации этого контингента больных