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Біохімічні та алелопатичні особливості Adonis vernalis, Allium ursinum та Leucojum vernum у Національному ботанічному саду імені М.М. Гришка НАН України
No full textThe article presents the results of a study on the content and dynamics of the accumulation of biogenic elements and brassinolides in plants of Adonis vernalis, Allium ursinum, and Leucojum vernum in Kyiv, Ukraine. Data is provided on allelopathic activity, content of macro- and microelements, phenolic compounds, and laccase activity in plants and the rhizosphere soil under the conditions of the M.M. Gryshko National Botanical Garden of the National Academy of Sciences of Ukraine (NBG). The plants from the collection of the NBG were used as objects of study in field experiments. The content of biogenic elements in plant tissues and soil was analyzed using an inductively coupled plasma spectrometer. The allelopathic analysis of soil was conducted using a direct bioassay method with Lepidium sativum seedlings as the test object. Phenolic compounds were extracted from the soil using the ion exchange (desorption) method. The content of brassinosteroids was measured spectrophotometrically at a wavelength of 450 nm. The content of laccase was measured spectrophotometrically at a wavelength of 530 nm.The results demonstrate that model plant species employ a wide range of physiological mechanisms throughout the vegetation period to enhance their resistance to abiotic factors. These mechanisms include maintaining potassium and calcium balance and utilizing hormonal compounds. Plants have been proven to have compensatory mechanisms in response to stress factors, substituting one biochemical marker of resistance with another. Both, brassinosteroids and silicon, contribute to the adaptive capacity of organisms
Статистичні характеристики та кореляції морфометричних ознак плодів Asparagus officinalis L. у Національному ботанічному саду імені М.М. Гришка НАН України
No full textThe current research was conducted in 2020–2023 on the botanical-geographical plot “Steppes of Ukraine” at the M.M. Gryshko National Botanical Garden of the NAS of Ukraine and was focused on ripe fruits of Asparagus officinalis. This study aimed to find out the main statistical characteristics of morphometric traits of A. officinalis fruits: fruit diameter, number of locules per fruit, number of seeds per fruit, number of seeds per locule, and to confirm or deny the hypothesis of positive pairwise correlations of the first three traits. Eighteen combinations of four morphometric traits were found in the A. officinalis fruits. For each morphometric feature of A. officinalis fruits, ten statistical characteristics were determined: arithmetic mean, median, mode, range of variation, oscillation coefficient, standard deviation, coefficient of variation, standard error of the mean, coefficient of skewness, and coefficient of kurtosis. The coefficient of variation showed that the number of seeds per fruit is the most variable of the studied morphometric traits of A. officinalis fruits, and the fruit diameter is the least variable. According to the comprehensive assessment of the coefficients of skewness and kurtosis, the distributions of the number of seeds per fruit and the diameter of the fruits are closest to the normal distribution. It was established that the correlations between pairs of such traits as fruit diameter and number of locules per fruit, fruit diameter and number of seeds per fruit, number of locules per fruit and number of seeds per fruit are positive, direct, and strong. Thus, considering the economic feasibility, it is more practical to collect A. officinalis fruits of a larger size to obtain a larger number of seeds. The results of this work are of interest for the morphology and biometrics of A. officinalis and its cultivation
BBCH модель сезонного розвитку Cydonia oblonga Mill. в Україні
No full textPhenology has not lost its relevance, especially now, when the global warming is making itself known more and more clearly. Phenological data obtained according to the BBCH system have a wide range of application: from the biological identification of global and regional weather and climate changes to the use in the selection of new cultivars of plants adapted to modern living conditions. We found out the BBCH model of phenological growth of 19 cultivars of Cydonia oblonga Mill. (Rosaceae) of the collection of the M.M. Gryshko National Botanical Garden, National Academy of Sciences of Ukraine (NBG). In the climatic conditions of Ukraine, quince goes through an entire cycle of seasonal growth. Codification of the phenological phases of growth according to the BBCH system showed that for quince, as for other fruit plants of the Rosaceae family, is characterized by eight of the ten principal stages of seasonal growth, in particular: the development of buds (principal growth stage 0: bud development), leaves (principal growth stage 1: leaf development), shoots (principal growth stage 3: shoot development), inflorescence (principal growth stage 5: inflorescence emergence), flowering (principal growth stage 6: flowering), fruit development and ripening (principal growth stage 7: fruit development; principal growth stage 8: maturity of fruit) and senescence and onset of dormancy (principal growth stage 9: senescence, beginning of dormancy). Cydonia oblonga has vegetative and vegetative-generative buds. It differs from some other fruit plants of the Rosaceae family by the specific course of the principal growth stage 5. Quince flowers are initiated from the apical meristem of one-year shoots, therefore they do not have phenophase 51, and at the stage of development 53 they are visually invisible due to the fact that they are tightly wrapped by leaves. The studied quince cultivars of the NBG collection are similar to each other in the course of most phenophases of seasonal development. The BBCH model of the seasonal growth of quince in Ukraine corresponds to two other comparable models that record the seasonal growth of this species in Spain (Murcia region) in a semi-arid Mediterranean climate with very mild winters and hot summers and Brazil (Pelotas region) in a warm tropical climate. These facts confirm the ecological plasticity of the species and its high adaptive and reproductive capacity, which can be the key to the expansion of the region of quince cultivation in Ukraine, including through the creation of industrial plantations
Перше повідомлення про знахідку Illinoia liriodendri (Monell, 1879) (Hemiptera, Aphididae) в Україні
No full textIllinoia liriodendri is reported for the first time in Ukraine as a new invasive species of aphids. It was found feeding on Liriodendron tulipifera at the ‘Olexandria’ State Dendrological Park of the NAS of Ukraine in June 2024
Model of the "department" ecosystem
Get PDFAn ecosystem model is proposed, which describes the main objects and their functions in such medium of a higher educational institution as a department. The main object of research in such models are conditions of the successful development and functioning of the department. In particular, the methods of planning an equal educational load for teachers, together with the employees of the university department and the management of the faculty are considered. The main actors in the ecosystem are teachers (called servers), who teach the courses. The proposed model makes it possible to simplify the drawing up of the schedule, to quickly respond to force majeure circumstances, necessary exchange of the teacher, etc. The properties of ecosystem models are verified by automata-network methods. Such ecosystem can be generalized and expanded by adding models of the faculty, university, and Ministry in order to control the work of the faculty, university, and ministry, the effectiveness of their functioning.Prombles in programming 2024; 2-3: 418-42
Formal verification of the properties of coreferent resolution model based on decision trees
Get PDFThe paper examines the problem of coreference resolution, which involves identifying objects - words or phrases in a text, that refer to the same real or imaginary entity. The solution of this task is explored for Ukrainianlanguage texts using decision trees, which autonomously structure themselves based on training data. Unlike other machine learning algorithms such as neural networks, decision trees allow for analysis of their internal structure through graphical representation. This feature facilitates explaining individual results produced by the tree, significantly easing formal verification of their properties. To create decision trees, vector representations of words (such as Elmo) and other linguistic features are used. After formation, decision trees are employed for binary classification of input pairs potentially referring to the same coreferent objects. Based on the obtained binary classifier, coreferent objects are grouped into clusters, followed by an evaluation of the clustering accuracy using specialized metrics. The paper provides a detailed description of the implemented application and the structure of the formed decision tree, which serves as the basis for further analysis. Additionally, the use of transition systems is proposed to construct a high-level specification model for coreference resolution. The transition system-based model enables analysis of application behavior on infinite state sequences, ensuring errorfree execution. Formalization is carried out, and automata models along with linear-temporal logic are used to verify a set of properties of the obtained specification. Büchi automata are created to accept words confirming the properties, and examples as well as counterexamples of the analyzed properties are found. The method defined in the paper serves as the foundation for creating automated analyzers for coreference resolution applications based on decision trees.Prombles in programming 2024; 2-3: 319-32
Modified model of the aggregated dead zone on examples of radionuclide transfer in natural hydrodynamic systems
Get PDFThis paper presents the results obtained during a detailed study of the aggregate dead zone model designed to describe the longitudinal transport and dispersion of dissolved substances in a channel flow. This model is based on a new approach to the description of advection and dispersion, which allows to adequately reproduce the concentrations of solutes observed in natural hydrodynamic systems with a high degree of accuracy. Instead of modelling the dissolved solute concentration continuously in both distance and time along the watercourse, the aggregate dead zone model uses a black box approach and considers the concentration at the chamber outlet (from the aggregate dead zone) as a function of the concentration at the chamber inlet and the current time. This approach significantly reduces the computational time and reduces the requirements for the amount of initial and boundary data. The mathematical apparatus of the extended model of the aggregated dead zone is presented, designed to analyse the transport of non-conservative radioactive contamination in real water bodies, taking into account the possible interaction of the radionuclide with suspended sediments and a layer of bottom sediments. The equations of the proposed model are a system of ordinary differential equations with a delayed argument. The results of modelling the distribution of 3 H as a result of releases from 14 nuclear reactors in the Russian section of the Loire River for six months with an hourly discreteness are presented. The results of modelling the propagation of sudden 90Sr releases in the Kyiv reservoir, which occurred in 1999 as a result of the Chornobyl disaster, are presented. The modelling was carried out with a daily discreteness. A comparison of the obtained model values of radionuclide concentrations and measurement data was carried out. The proposed model has a comparative simplicity, much lower requirements for the amount of initial and boundary data, and very little time required for calculations.Prombles in programming 2024; 2-3: 45-5
Structure of the algorithm for modeling optimal movement of a compound dynamic system
Get PDFThe work is devoted to the development of the structure of the algorithm for modeling the optimal movement of complex dynamic systems (SDS) along a branched trajectory. Complex systems are called systems consisting of separate subsystems, the flight trajectories of which differ and are called branched. Branched trajectories should consist of trajectory segments, the first of which will be common to the entire SDS, and the other trajectory branches will be different, as each subsystem moves to its goal along its own trajectory segment. The proposed algorithm makes it possible to optimize such trajectories in real time and to carry out operational correction of SDS trajectories in the event of the occurrence of unpredictable influencing factors. It is known that the effectiveness of the SDS functioning between structural transformations depends on the coordinates of the mutual location and speed of each subsystem and the choice of optimal moments of time for structural transformations. The efficiency of determining these parameters during the flight is fundamentally important. The necessary conditions for the optimality of the trajectory of the SDS movement are found, which are universal for problems with any finite number of trajectory branches. The implementation of the proposed conditions will allow to reduce the number of computational procedures in the control calculations in conditions of uncertainty of the initial conditions. These conditions are the methodological basis for the development of computational algorithms for modeling the optimal trajectories of the SDS movement. The necessary optimality conditions have a clear physical meaning and are technological and user-friendly. The results of the research presented in the article are important and relevant for the construction of the laws of trajectory control of existing and prospective SDS.Prombles in programming 2024; 2-3: 69-7
Method of managing the execution of tasks of a multithreaded program according to a given dependency graph
Get PDFPerformance is one of the main non-functional requirements for software. As a result of the increase in the number of cores in central processing units in recent decades, the use of multithreading technology has become a primary means of improving software performance. This study analyzes the problems that arise from developing multithreaded programs and ways to address them. A method for managing the execution of tasks in a multithreaded program based on a given dependency graph is proposed and its implementation in the C++ language is demonstrated. Its aim is to reduce the resource intensity of software development and increase its reliability by addressing problems typical of developing multithreaded programs. The results of experimental research on a test set of tasks are provided, demonstrating increased performance through the use of the proposed method.Prombles in programming 2024; 2-3: 239-24
Modified method of searching keywords and keyterms in text data
No full textThis article discusses the issue of automated search for keywords and key terms in text data. To improve the efficiency of the tools of automated search for keywords in the text according to the criteria of absolute accuracy and Jaccard index, a modification of one of the most modern methods for searching for keywords has been developed. A modification of the existing hybrid keyword search method is proposed. It takes into account complex dependencies between pairs of words in the text to determine multi-word expressions, which, unlike the original method, allows finding key terms consisting of several words. Tests of the created modification of the hybrid method of searching for key terms showed the effectiveness of its use for searching for key terms in texts in comparison with existing analogues.Prombles in programming 2024; 1: 12-2