138 research outputs found

    On the Choice of Numerical Methods for Solving Dynamic Equations for Control Systems with Embedded Calculating Tools

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    Approaches to choice of optimum method as for accuracy and amount of computation at the integration step that makes it possible to range numerical implementation methods for different levels of acceptable error based on evaluation of optimality criterion.Розглянуто підходи вибору оптимального методу щодо точності та обсягу обчислень на кроці інтегрування, що дає змогу на підставі оцінки значення критерію оптимальності зробити ранжування методів числової реалізації для різних рівнів допустимої похибки

    Modeling the impact of weather and climatic conditions and nutrition variants on the yield of spring barley varieties (Hordeum vulgare L.)

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    Crop yield is a result of the interaction between plant genetic traits, soil properties, agrotechnology and climatic regimes. Low yield tend to be formed in regions where it is limited to the extent of water availability, heat stress and the short duration of the grain filling period. High temperature and drought stress are projected to reduce crop yields and threaten food security. The article presents the results of studies on the effectiveness of treatment of spring barley crops with modern growth-regulating drugs on the background of mineral fertilizers, carried out in different weather and climatic conditions in 2013–2017 yrs on the Southern chernozem in the conditions of Steppe of Ukraine. It was studied the influence of weather and climatic conditions, varietal characteristics of spring barley and nutrition variants on the formation of grain yield. It was determined that the cultivation of spring barley, the introduction of pre-sowing cultivation of mineral fertilizer at a dose of N30P30 (background) and the use of crop foliar fertilizing at the beginning of the phase of stooling and earing by the complex organo-mineral fertilizer Escort bio created favorable conditions for the growth and development of plants of the studied varieties, which in turn had a positive effect on grain yield. Thus, according to this variant of nutrition, on average, during the years of research, it was formed the yield of 3.25–3.61 t ha-1 grains depending on the studied variety. Results of researches showed that weather conditions during the years of research significantly influenced on the productivity of spring barley varieties. In 2016 the amount of precipitation was the highest (174.0 mm), the temperature during vegetation of spring barley was +14.9 °C. In 2013 the amount of precipitation was the lowest (67.4 mm), the temperature was +18.5 °C. The lowest crop yield was formed in 2013, and the highest yield was formed in 2016. Studies showed that the influence of weather factors in various interfacial periods of growth and development of spring barley was significant enough for the manifestation of signs of yield and its elements and is more dependent on rainfall

    Formation of photosynthetic and grain yield of spring barley (Hordeum vulgare L.) depend on varietal characteristics and plant growth regulators

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    ArticleThe aim of the study was to determine the efficiency of the barley treatment crops with modern retrograde preparations on the background of the mineral fertilizers introduction into the photosynthetic activity of crops and grain yield. The experiments were carried out in 2013 -2017 on the southern black soil in the conditions of the Ukrainian Steppe. On the basis of the study results, it was determined that the introduction of irrigated fertilizer barley in a dose of N30P30 (background) under pre-sowing cultivation and the application of extra-root crop supplements at the phases beginning of the barley outflow straw into the tube and the organoleptic fermentation of Organic D2 and natural microbial complex Escort - Bio creates favorable conditions for the formation at the optimal levels of photosynthetic parameters and grain yield. Thus, on average, over the years of research and by factor variety, grain yield on these experimental variants was 3.37–3.41 t ha-1 , which exceeded its level on uncontrolled control by 0.71–0.75 t ha-1 or 26.7–28.2%. Based on the study results, the use of modern regenerating agents against the background of mineral fertilizers can be recommended as an expedient and effective measure of spring barley raising the productivity

    On extending actions of groups

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    Problems of dense and closed extension of actions of compact transformation groups are solved. The method developed in the paper is applied to problems of extension of equivariant maps and of construction of equivariant compactifications

    Permian diamictites in northeastern Asia: Their significance concerning the bipolarity of the late Paleozoic ice age

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    © 2015 Elsevier B.V. Despite a lack of detailed sedimentologic analyses, diamictites in the Middle Permian Atkan Formation were previously interpreted as glaciomarine and glacially-influenced marine deposits. This interpretation allowed this unit to play a prominent role in paleoclimatic and biogeographical reconstructions associated with presumed bipolar glaciation during the late Paleozoic ice age (LPIA). In this sense, the LPIA is considered to be a close analog to bipolar glaciation and climate change during the Cenozoic. Here, results are presented that challenge the glacigenic interpretation for these strata and negate interpretations of the bipolar nature of the LPIA. The 400 to 1500-m-thick Atkan Formation was deposited in back-arc basins associated with activity of the Okhotsk-Taigonos volcanic arc along the leading edge of Pangea as it drifted across the North Polar Circle. The occurrence of tuffs, volcanic clasts, and glass shards indicate derivation from a nearby arc. Cooling and solidification of some clasts during sedimentation is suggested by the occurrence of clasts with embayments and protrusions that extend into the surrounding matrix, clasts with columnar-like jointing, and alteration of the matrix surrounding some clasts. CA-TIMS dating of tuff zircons indicate a late Capitanian age, which is consistent with fossils within the strata. Bedded diamictites deposited as debrites dominate. These diamictites, which occur as tens of m thick downlapping packages that thicken then thin upward, were deposited as prograding and abandoning sediment gravity-flow fans. Chaotic and folded strata formed as slumps. Graded sandstones and conglomerates were deposited as turbidites, and mudstones were deposited as mudflows, low-density turbidites, and hemipelagic deposits. Striated clasts and outsized clasts piercing bedding were not observed in the study area. Strata above and below the Atkan Formation contain abundant graded beds and deep-water trace fossils indicating deposition as turbidites. The combination of debrites, turbidites, slumps, volcanic grains (clasts, glass, and tuffs), and an absence of glacigenic indicators suggest that Atkan strata were deposited in deep-water basins associated with the development of the volcanic arc rather than due to glacial activity. These findings are significant as they require reconsideration of current views of LPIA glaciation and suggest that ice sheets were limited to Gondwana

    Crystall Structure Compounds Type Hg5C2X8 (C−Ga, In; X−S, Se, Te) and Solid Solution

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    Используя методы РФА та РСА анализов, изучена структура соединений состава Hg5C2X8 (C–Ga, In; X–S, Se, Te) и твердых растворов на их основе. Соединения Hg5Ga2Se8, Hg5In2Se8, Hg5Ga2Te8 та Hg5In2Te8 кристализируются в ПГ F 4 3m с параметром элементарной ячейки а = 1,16876(2) нм, 1,18876(2) нм, 1,24738(2) нм и 1,26723(2) нм соответственно. Using X-ray phase and X-ray structure analysis methods, crystal structure compounds type Hg5C2X8 (C–Ga, In; X–S, Se, Te) and solid solution were investigated. Compaunds Hg5Ga2Se8, Hg5In2Se8, Hg5Ga2Te8 and Hg5In2Te8 has crystal structure of the F4 3m with а = 1,16876(2) nm, 1,18876(2) nm, 1,24738(2) nm and 1,26723(2) nm

    Audit of Digital Civic Space in the Modern School: from Teacher to Creative Leader

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    The article is dedicated to modern approaches to development of digital civic space of the modern school, in the context of the research results in modern neuroscience, which is a new phenomenon in Ukraine. A brief analysis of results of recent scientific researches that raise the issue of digital citizenship in postmodern times is given. Theoretical principles and practical experience of European countries to create a digital civic space are considered. Definitions of “civic consciousness” and “digital citizenship”, “creativity”, “postmodernism” are given. The theoretical principles of research in neurosciencees in the system of pedagogical education are considered. Modern approaches to development of digital competence of participants in the educational process are singled out. Vision of the Council of Europe on the components of digital citizenship is considered, which is seen as empowering students and acquiring the necessary digital skills for successful self-realization in the postmodern era. A brief description of the Conceptual Model of Digital Citizenship Education adopted by the Council of Europe is given, emphasizing the importance of systematicity and consistency in its implementation. Prerequisites for achieving results of this Conceptual Model are generalized and highlighted. Tools for auditing the digital civic space of a modern school are proposed, which allows to determine the level of development of basic skills of a digital citizen in all participants in the educational process on the basis of modern neuroscience research results. The main audit methods for this tool are surveys, audit of school records and determination of access to digital technologies. The importance of integrating the content of the Conceptual Model of Education on Digital Citizenship into the content of subjects is emphasized, which should be reflected in the school documentation at different levels: from the Educational Program to the teacher’s lesson plan. Criteria and indicators for auditing the school’s digital civic space are detailed

    Bacterial formate dehydrogenase. Increasing the enzyme thermal stability by hydrophobization of alpha-helices

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    AbstractNAD+-dependent formate dehydrogenase (EC 1.2.1.2, FDH) from methylotrophic bacterium Pseudomonas sp.101 exhibits the highest stability among the similar type enzymes studied. To obtain further increase in the thermal stability of FDH we used one of general approaches based on hydrophobization of protein α-helices. Five serine residues in positions 131, 160, 168, 184 and 228 were selected for mutagenesis on the basis of (i) comparative studies of nine FDH amino acid sequences from different sources and (ii) with the analysis of the ternary structure of the enzyme from Pseudomonas sp.101. Residues Ser-131 and Ser-160 were replaced by Ala, Val and Leu. Residues Ser-168, Ser-184 and Ser-228 were changed into Ala. Only Ser/Ala mutations in positions 131, 160, 184 and 228 resulted in an increase of the FDH stability. Mutant S168A was 1.7 times less stable than the wild-type FDH. Double mutants S(131,160)A and S(184,228)A and the four-point mutant S(131,160,184,228)A were also prepared and studied. All FDH mutants with a positive stabilization effect had the same kinetic parameters as wild-type enzyme. Depending on the position of the replaced residue, the single point mutation Ser/Ala increased the FDH stability by 5–24%. Combination of mutations shows near additive effect of each mutation to the total FDH stabilization. Four-point mutant S(131,160,184,228)A FDH had 1.5 times higher thermal stability compared to the wild-type enzyme

    LEETECH facility as a flexible source of low energy electrons

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    A new versatile facility LEETECH for detector R&D, tests and calibration is designed and constructed. It uses electrons produced by the photoinjector PHIL at LAL, Orsay and provides a powerful tool for wide range R&D studies of different detector concepts delivering "mono-chromatic" samples of low energy electrons with adjustable energy and intensity. Among other innovative instrumentation techniques, LEETECH will be used for testing various gaseous tracking detectors and studying new Micromegas/InGrid concept which has very promising characteristics of spatial resolution and can be a good candidate for particle tracking and identification. In this paper the importance and expected characteristics of such facility based on detailed simulation studies are addressed

    Effect of agrotechnological elements on milk thistle (Silynum marianum) productivity

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    The milk thistle is a highly valuable medicinal plant, widely used in treatment of liver diseases. Soil-climate conditions of the steppe zone of Ukraine are favourable for crop cultivation. The goal of the study was to determine relations between milk thistle productivity and elements of cultivation technology, viz., primary tillage depth (14–16 and 20–22 cm), inter-row spacing (30, 45, 60 cm), timing of sowing (3rd decade of March, middle of April, 3rd decade of April) and mineral fertilizer application doses (no fertilizers, N45P45, N90P90). Field trials were carried out during the period from 2010 to 2012 on the irrigated lands of the Institute of Rice of the National Academy of Agrarian Sciences of Ukraine by using the split plot design method in four replications. The climate of the territory of the trials is typical for the steppe zone. The soil type was dark-chestnut residual solonetz middle-loamy soil. We used the Yuhoslava variety of milk thistle in the trials. Cultivation technology was standard, excluding the studied factors. The results of the trials showed significant impact of all the studied cultivation technology elements on milk thistle seed and oil yields. The maximum average seed (1.66 t/ha) and oil (489 kg/ha) yields were obtained under the primary tillage at the depth of 20–22 cm, inter-row spacing of 60 cm, sowing in the 3rd decade of March, applying mineral fertilizers in a dose of N90P90. The highest input in seed and oil yields rise was made by the mineral fertilizers, which increased milk thistle productivity by 1.57 times comparatively with non-fertilized treatments. We also established a strong direct interrelationship between seed and oil yield: coefficient of determination was 0.96. Results of the current study are slightly limited, so further investigations in the field of milk thistle cultivation technology development and improvement are required to provide Ukrainian farmers with scientifically grounded agrotechnology of this valuable medicinal plant
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