637 research outputs found

    Выбор и обоснование применения технологий очистки призабойной зоны пласта в различных геолого-технических условиях на месторождениях Западной Сибири

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    Объектом исследования являются осложнения, возникающие в призабойной зоне пласта при эксплуатации добывающих и нагнетательных скважин, а также методы воздействия на призабойную зону пласта. Цель исследования – анализ методов и технологий очистки призабойной зоны пласта в различных геолого-технических условиях на месторождениях Западной Сибири. В процессе исследования были рассмотрены причины загрязнения призабойной зоны пласта. Проведен анализ стандартных технологий очистки призабойной зоны.The object of research is the complications that occur in the bottom-hole zone of the formation during the operation of production and injection wells, as well as methods of influence on the bottom-hole zone of the formation. The purpose of the study is to analyze methods and technologies for cleaning the bottom-hole zone of the formation in various geological and technical conditions in the fields of Western Siberia. In the course of the study, the causes of contamination of the bottom-hole zone of the formation were considered

    Impact of the ash deposits from coal combustion on thermal conditions of the furnace pipes

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    One of the problems of thermal power plants is the contamination of heating surfaces that arises during the boiler unit operation while combusting the solid fuel. The main part of the energy is consumed by pipes forming the furnace. Non-combustible mineral part of the fuel in the form of the ash and slag accumulates on the heating surfaces and thereby prevents heating of the working liquid. Therefore, boiler requires higher fuel consumption to maintain the operating conditions. Violation of the thermal conditions of heating surfaces in consequence of contamination causes the negative effects on metal pipes right up to failure. This problem is urgent due to the fact that information about the process of slagging and its effect on the thermal conditions of the heating surface operation enables the possibility to minimize the negative consequences. This possibility is achieved by adjusting the thermal conditions of the combustion process in the furnace with the periodic cleaning of the heating surfaces

    Analyzing embedded device programming specifications in critical system to design programming guidelines

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    Безопасность программного обеспечения является важной характеристикой, показывающей вероятность правильности работы программы при различных условиях эксплуатации. Однако разработчики встроенного программного обеспечения не всегда уделяют должное внимание этому аспекту, особенно в критически важных системах. В данной работе рассматриваются международные стандарты и сертификаты безопасности программного обеспечения. На основе исходного кода снятого с производства электрохирургического медицинского аппарата ЭХВЧ-80 компании НПО "НИКОР" анализируются вопросы обоснованности выбора языка программирования и использованной архитектуры. Приводится алгоритм работы программы, а также описаны основные задачи, выполняемые микроконтроллером. В заключительной части статьи, на основе анализа программного обеспечения автор предлагает рекомендации по упрощению поддержки и возможные варианты уменьшения ошибок, как в коде, так и в архитектуре разрабатываемого приложения. Результаты исследования позволяют повысить безопасность ПО, особенно в критически важных системах.Software safety is an important characteristic, which indicates the probability of correct program operationunder different operating conditions. However, embedded software developers do not always focus on this aspect,especially in critical systems. The present article discusses the international software security standards andcertificates. The author studies the source code of the presently discontinued electrosurgical device EHVCh-80 byNPO "NIKOR" and analyzes the issues of validity of choosing the programming language and architecture. Thepaper provides the algorithm of the program's operation and describes the main tasks performed by themicrocontroller. In conclusion, the author uses the results of this software's analysis to offer recommendations tosimplify software support and possible options to reduce errors, both in the code and in the architecture of thedeveloped application. The results of this research allow increasing software safety, especially in critical systems

    Un estudio comparativo de actuadores Piezoeléctricos y Magnetoestrictivos para estructuras inteligentes

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    [EN] This paper introduces a comparative analysis of Piezoelectric (PZ) and Magnetostrictive (MS) actuators as components in smart structures. There is an increasing interest in functional structures which are able to adapt to external or internal perturbations, i.e. changes in loading conditions or ageing. Actuator technologies must perform concomitantly as sensors and actuators to be applicable in smart structures. In this paper we will comparatively analyze the possibility of using PZ and MS actuators in smart structures and in so doing their capability to act concomitantly as sensors and of modifying their material characteristics. We will also focus on the analysis of how them can be integrated in structures and on the analysis of the most appropriate structures for each actuator. The operational performance of PZ (Stacks) and MS actuators will be compared and eventually some conclusions will be drawn.[ES] Este artículo presenta un estudio comparativo de actuadores Piezoeléctricos (PZ) y Magnetoestrictivos (MS) como elementos integrantes de estructuras inteligentes. Existe un interés creciente en estructuras activas que puedan adaptarse a perturbaciones tanto internas como externas, por ejemplo, ante cambios en carga estructural o ante su envejecimiento. Para que un actuador forme parte de una estructura inteligente, debe poder actuar también como sensor. Este artículo presenta un estudio comparativo del uso de actuadores PZ y MS en estructuras inteligentes y, como consecuencia, de su habilidad para actuar y medir simultáneamente así cómo para modificar sus características mecánicas. Nos centraremos también en el análisis de como pueden integrase en estructuras y cuales son las más indicadas para cada actuador. Se compararán las características operacionales de los actuadors PZ multicapa y los MS.Peer reviewe

    Analysis of aberrantly methylated sequnces in circulating DNA from blood of patients with lung cancer

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    Malignant cell transformation is accompanied by two processes of DNA methylation changes: promoter hypermethylation of specific genes and hypomethylation of retrotransposons. The composition of circulating DNA (cirDNA) from plasma and cell-surface-bound circulating DNA (csb-cirDNA) was shown earlier to be altered in the blood of cancer patients due to accumulation of tumor-specific aberrantly methylated DNA fragments, which are currently considered valuable cancer markers. The present study compares LINE-1 retrotransposon methylation patterns in plasma cirDNA and csb-cirDNA from untreated lung cancer patients (LC) and healthy donors. Concentrations of methylated LINE-1 region 1 copies (LINE-1met) were assayed by real-time methylation-specific PCR. In order to normalize the LINE-1 methylation level, the LINE-1 region 2 concentration was evaluated, which was independent of the methylation status (LINE-1Ind). We recorded an statistically significant increase of the LINE-1 methylation index determined as (LINE-1met/LINE-1Ind) due to the profound LINE-1Ind decrease (Mann-Whitney test, p = 0.005). Plasma cirDNA demonstrated no difference in the ratio LINE-1met/LINE-1Ind between LC patients and healthy donors (p = 0.40). The data obtained agree with our earlier results, which showed that csb-cirDNA was a highly informative material for lung cancer diagnostics
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