24 research outputs found

    Processing of heavy residual feedstock on Mo/Al[2]O[3]-catalytic systems obtained using polyoxomolybdate compounds

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    The urgency of creating new efficient catalysts for the processes of deepening oil refining rises on the background of stricter requirements for the quality of motor fuels, as well as the deterioration of the quality of crude oil for processing, and an increase in the number of distillates of secondary processes involved in the production of commodity petroleum products. In this work, alumina-catalytic systems were synthesized using polyoxomolybdate compounds. The morphology, structure and phase composition of the synthesized catalytic systems were studied using the following analysis methods: scanning electron microscopy, microelement analysis, X-ray phase analysis, X-ray diffraction, electron spectroscopy. It has been established that the Mo/AI[2]O[3] system is active in the process of thermal catalytic conversion of heavy residual raw materials

    Diet and subsistence in Bronze Age pastoral communities from the southern Russian steppes and the North Caucasus

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    The flanks of the Caucasus Mountains and the steppe landscape to their north offered highly productive grasslands for Bronze Age herders and their flocks of sheep, goat, and cattle. While the archaeological evidence points to a largely pastoral lifestyle, knowledge regarding the general composition of human diets and their variation across landscapes and during the different phases of the Bronze Age is still restricted. Human and animal skeletal remains from the burial mounds that dominate the archaeological landscape and their stable isotope compositions are major sources of dietary information. Here, we present stable carbon and nitrogen isotope data of bone collagen of 105 human and 50 animal individuals from the 5th millennium BC to the Sarmatian period, with a strong focus on the Bronze Age and its cultural units including Maykop, Yamnaya, Novotitorovskaya, North Caucasian, Catacomb, post-Catacomb and late Bronze Age groups. The samples comprise all inhumations with sufficient bone preservation from five burial mound sites and a flat grave cemetery as well as subsamples from three further sites. They represent the Caucasus Mountains in the south, the piedmont zone and Kuban steppe with humid steppe and forest vegetation to its north, and more arid regions in the Caspian steppe. The stable isotope compositions of the bone collagen of humans and animals varied across the study area and reflect regional diversity in environmental conditions and diets. The data agree with meat, milk, and/or dairy products from domesticated herbivores, especially from sheep and goats having contributed substantially to human diets, as it is common for a largely pastoral economy. This observation is also in correspondence with the faunal remains observed in the graves and offerings of animals in the mound shells. In addition, foodstuffs with elevated carbon and nitrogen isotope values, such as meat of unweaned animals, fish, or plants, also contributed to human diets, especially among communities living in the more arid landscapes. The regional distinction of the animal and human data with few outliers points to mobility radii that were largely concentrated within the environmental zones in which the respective sites are located. In general, dietary variation among the cultural entities as well as regarding age, sex and archaeologically indicated social status is only weakly reflected. There is, however, some indication for a dietary shift during the Early Bronze Age Maykop period

    The Eurasian Modern Pollen Database (EMPD), version 2

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    The Eurasian (née European) Modern Pollen Database (EMPD) was established in 2013 to provide a public database of high-quality modern pollen surface samples to help support studies of past climate, land cover, and land use using fossil pollen. The EMPD is part of, and complementary to, the European Pollen Database (EPD) which contains data on fossil pollen found in Late Quaternary sedimentary archives throughout the Eurasian region. The EPD is in turn part of the rapidly growing Neotoma database, which is now the primary home for global palaeoecological data. This paper describes version 2 of the EMPD in which the number of samples held in the database has been increased by 60 % from 4826 to 8134. Much of the improvement in data coverage has come from northern Asia, and the database has consequently been renamed the Eurasian Modern Pollen Database to reflect this geographical enlargement. The EMPD can be viewed online using a dedicated map-based viewer at https://empd2.github.io and downloaded in a variety of file formats at https://doi.pangaea.de/10.1594/PANGAEA.909130 (Chevalier et al., 2019)Swiss National Science Foundation | Ref. 200021_16959

    The Eurasian Modern Pollen Database (EMPD), version 2

    Get PDF
    The Eurasian (nee European) Modern Pollen Database (EMPD) was established in 2013 to provide a public database of high-quality modern pollen surface samples to help support studies of past climate, land cover, and land use using fossil pollen. The EMPD is part of, and complementary to, the European Pollen Database (EPD) which contains data on fossil pollen found in Late Quaternary sedimentary archives throughout the Eurasian region. The EPD is in turn part of the rapidly growing Neotoma database, which is now the primary home for global palaeoecological data. This paper describes version 2 of the EMPD in which the number of samples held in the database has been increased by 60% from 4826 to 8134. Much of the improvement in data coverage has come from northern Asia, and the database has consequently been renamed the Eurasian Modern Pollen Database to reflect this geographical enlargement. The EMPD can be viewed online using a dedicated map-based viewer at https://empd2.github.io and downloaded in a variety of file formats at https://doi.pangaea.de/10.1594/PANGAEA.909130 (Chevalier et al., 2019).Peer reviewe

    Cryogels: Morphological, structural and adsorption characterisation

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    A Combinatorial Model for Determining Information Loss in Organizational and Technical Systems

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    A combinatorial model is proposed for determining the probability and information losses in an organizational and technical system (OTS) under destructive external influences. Mathematical expressions are obtained to determine the loss of information in the clusters of the control system. It is shown that the use of this model for a quantitative analysis of the probability of occurrence of events and information losses in the control system, under varying external influences on the dynamic OTS, makes it possible to carry out a quantitative analysis and synthesis of the structure of the control system that is resistant to destructive external influences. A decomposition of the probabilities of occurrence of events and the corresponding loss of information by the levels of the hierarchy of the analyzed air traffic control system is presented. The achieved result is due to the sensitivity of the model for determining information losses relative to changes in the structure of the system and destructive external influences, as well as the use of the mathematical apparatus in combinatorial analyses

    A Combinatorial Model for Determining Information Loss in Organizational and Technical Systems

    No full text
    A combinatorial model is proposed for determining the probability and information losses in an organizational and technical system (OTS) under destructive external influences. Mathematical expressions are obtained to determine the loss of information in the clusters of the control system. It is shown that the use of this model for a quantitative analysis of the probability of occurrence of events and information losses in the control system, under varying external influences on the dynamic OTS, makes it possible to carry out a quantitative analysis and synthesis of the structure of the control system that is resistant to destructive external influences. A decomposition of the probabilities of occurrence of events and the corresponding loss of information by the levels of the hierarchy of the analyzed air traffic control system is presented. The achieved result is due to the sensitivity of the model for determining information losses relative to changes in the structure of the system and destructive external influences, as well as the use of the mathematical apparatus in combinatorial analyses

    A Digital Device for Automatic Checking of Homework Assignments in the Digital Circuits Course

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    This paper considers a digital device for automatic checking of homework assignments in the digital circuits course. The assignment is to make a digital circuit corresponding to a given logical expression; the circuit is comprised of elementary logic gates. The process of manual testing the built circuit is very labor-intensive because checking a circuit with N inputs variables requires checking the correctness of the output variable for 2N cases. We propose automating this pro-cess with a special digital device. The device is comprised of a microcontroller connected to the circuit tested. The microcontroller is connected to a personal computer with an application written in C# for executing the main operations of the testing process. During testing, the student chooses from a database or enters the logical expression corresponding to the circuit tested. For the expression, the software generates truth tables where actual and required responses of the circuit are given. Actual circuit responses are acquired by probing the circuit via the microcontroller, and the expected values are calculated from the logical expression. The truth tables are then presented to the student with a message of whether the circuit works correctly or not. The device was integrated into the process of checking homework assignments in the digital electronics course, and it significantly sped up the process of checking homework assignment circuits, resulting in better education quality

    Development of Adaptive Expert System of Information Security Using a Procedure of Clustering the Attributes of Anomalies and Cyber Attacks

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    The paper presents results of the research aimed at the further development of models for the intelligent systems of recognition of cyber threats, anomalies and cyber attacks.A structural scheme of adaptive expert system (AES) of information security, capable of self-learning, is proposed, which takes into account potential errors of the third kind, which may arise and accumulate while training a system of intelligent detection of complex targeted cyber attacks and preliminary process of splitting a space of attributes of the objects of recognition. We developed a model for calculating information criterion of functional effectiveness, based on entropic and distance criteria of Kullback-Leibler in the course of clustering the attributes of objects of recognition in computer systems, which allows obtaining input fuzzy classification training matrix. A procedure for the operation of AES as an element of the system for intelligent recognition of cyber threats (SIRCT) was explored in the training mode by a priori classified training matrix that allowed us to build correct decisive rules for the recognition of cyber attacks.We designed AES "Threat Analyzer" and conducted its test research under conditions of real CoS performance at several enterprises. It was found that the proposed model of AES learning makes it possible to achieve results of the recognition of the standard classes of cyber attacks at the level from 76.5 % to 99.1 %, which is at the level of recognition effectiveness by the best hybrid neural networks and genetic algorithms
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