Main Types Of Models Research Articles

Modeling the proof strength of pipe steels tempered with the application of artificial intelligence methods

The paper demonstrates the results of modeling the proof strength in pipe steels improved by tempering heat treatment. The main types of models used in this study are described, and information about the pros and cons of different approaches to modeling the target variable is summarized. Empirical equations relating hardness to yield strength and tensile strength are given. The role of the parameter n in these equations is indicated. The reasons for choosing the applied set of independent variables in the models are explained. The distribution of the target variable in the data sample is shown, and information about the feature space used for each of the models is provided. A general description of the source data is given. The structure of the main data sample is studied by the DBSCAN clustering method and the t-SNE dimension reduction algorithm. The reason for splitting the sample into clusters is substantiated in the context of reducing the spread of the predicted value of proof strength. The effectiveness of splitting the sample is estimated by using the measure of the spread of n. Various regression models for predicting yield strength are compared. It is shown that the regression model based on gradient boosting over the decision trees (LightGBM) has the smallest prediction error among the models considered. The permutation significance of the features of the model with the smallest prediction error is determined, the calculated significance of the features being compared with that from the metallurgical theory. The validity of the obtained prediction models is evaluated in view of the significance of the features and the metric estimate used in this study. The hypothesis of using a proxy variable (n) obtained from theoretical calculations as a predictor in the yield strength prediction model is tested. It is demonstrated that the application of the grouping method together with the parameter n makes it possible to obtain satisfactory prediction results on a smaller feature space.

Machine Learning Methods to Increase the Energy Efficiency of Buildings

Predicting a building’s energy consumption plays an important role as it can help assess its energy efficiency, identify and diagnose energy system faults, and reduce costs and improve climate impact. An analysis of current research in the field of ensuring the energy efficiency of buildings, in particular, their energy assessment, considering the types of models under consideration, was carried out. The principles, advantages, limitations, and practical application of the main data-based models are considered in detail, and priority future directions for forecasting the energy efficiency of buildings are highlighted. It is shown that the effectiveness of the methods is different for the main types of models and depends on the following factors: input data and parameters, the type and quality of available data for training, the suitability of the method for a specific type of model, etc. The need to consider the element of uncertainty when forecasting energy consumption due to the impossibility of accurate modeling of meteorological factors and the behavior of residents is emphasized. Therefore, machine learning methods, particularly deep learning-based models, are chosen to represent complex nonlinear input-output relationships, as they show higher performance than statistical time series forecasting methods. The analysis of published works revealed a lack of works describing a comprehensive energy forecasting information system for use in commercial projects. We proposed a new approach to combining semantic modeling and machine learning technologies for the energy management system of smart buildings, using the knowledge system of the semantic model we developed.

Düşük Kapsamlı WGS Verileri Kullanılarak Hızlı ve Yüksek Doğruluklu Guppy Baz Çağırma Modellerinin Varyant Çağırma Üzerine Etkisinin İncelenmesi

Long-read sequencing technologies such as Oxford Nanopore Technologies (ONT) enabled researchers to sequence long reads fast and cost-effectively. ONT sequencing uses nanopores integrated into semiconductor surfaces and sequences the genomic materials using changes in current across the surface as each nucleotide passes through the nanopore. The default output of ONT sequencers is in FAST5 format. The first and one of the most important steps of ONT data analysis is the conversion of FAST5 files to FASTQ files using “base caller” tools. Generally, base caller tools pre-trained deep learning models to transform electrical signals into reads. Guppy, the most commonly used base caller, uses 2 main model types, fast and high accuracy. Since the computation duration is significantly different between these two models, the effect of models on the variant calling process has not been fully understood. This study aims to evaluate the effect of different models on performance on variant calling.
 In this study, 15 low-coverage long-read sequencing results coming from different flow cells of NA12878 (gold standard data) were used to compare the variant calling results of Guppy. 
 Obtained results indicated that the number of output FASTQ files, read counts and average read lengths between fast and high accuracy models are not statistically significant while pass/fail ratios of the base called datasets are significantly higher in high accuracy models. Results also indicated that the difference in pass/fail ratios arises in a significant difference in the number of called Single Nucleotide Polymorphisms (SNPs), insertions and deletions (InDels). Interestingly the true positive rates of SNPs are not significantly different. These results show that using fast models for SNP calling does not affect the true positive rates statistically. The primary observation in this study, using fast models does not decrease the true positive rate but decreases the called variants that arise due to altered pass/fail ratios. Also, it is not advised to use fast models for InDel calling while both the number of InDels and true positive rates are significantly lower in fast models.
 This study, to the best of our knowledge, is the first study that evaluates the effect of different base calling models of Guppy, one of the most common and ONT-supported base callers, on variant calling.

Methodology of selection and synthesis of mathematical models of the epizootic process

The epizootic process (EP) is a continuous process of the emergence and spread of explicit and latent infections of animals. In some zoonoses, the study of EP by experimental studies can have negative consequences for human health. Therefore, the development of mathematical models of EP is of great practical importance. The purpose of the work is to consider the principles of the methodology for selecting and synthesizing EP models based on the mathematical theory of epidemics (MTE). Of the existing two main types of models are considered - deterministic and stochastic, their advantages and disadvantages are noted in connection with the main parameters used in the modeling of EP. An analytical review of mathematical models of Kermack (W.O.Kermack) and McKendrick; Weiss (George H. Weiss) for the study of EP is presented. Of the existing two main types of models are considered - deterministic and stochastic, their advantages and disadvantages are noted in connection with the main parameters used in the simulation of the EP. The issue of the methodology of selection and synthesis of models of the epizootic process for further forecasting of the most common viral and bacterial diseases of animals using models existing in the mathematical theory of epidemics is considered. The principles of the methodology for the selection and synthesis of MTE models using state graphs and tables of transition intensity models are considered. It is established that the method of selecting a stochastic MTE model for a specific disease or model synthesis uses a table of transition intensity models. It is concluded that the choice between deterministic and stochastic models is determined by the population size, the stage of epizootic/epidemic development, and the requirements for the accuracy of mathematical modeling. The proposed methodology for the selection and synthesis of mathematical models of EP allows you to build a mathematical model for predicting the distress of farms at the regional level. In recent years, there has been a tendency to switch to the use of simulation models and the creation of a bank of mathematical models for predicting epizootic situation indicators based on time series analysis.

Modelling of the LTDE-SD radionuclide diffusion experiment in crystalline rock at the Äspö Hard Rock Laboratory (Sweden)

This study shows a comparison and analysis of results from a modelling exercise concerning a field experiment involving the transport and retention of different radionuclide tracers in crystalline rock. This exercise was performed within the Swedish Nuclear Fuel and Waste Management Company (SKB) Task Force on Modelling of Groundwater Flow and Transport of Solutes (Task Force GWFTS).Task 9B of the Task Force GWFTS was the second subtask within Task 9 and focused on the modelling of experimental results from the Long Term Sorption Diffusion Experiment in situ tracer test. The test had been performed at a depth of about 410m in the Äspö Hard Rock Laboratory. Synthetic groundwater containing a cocktail of radionuclide tracers was circulated for 198 days on the natural surface of a fracture and in a narrow slim hole drilled in unaltered rock matrix. Overcoring of the rock after the end of the test allowed for the measurement of tracer distribution profiles in the rock from the fracture surface (A cores) and also from the slim hole (D cores). The measured tracer activities in the rock samples showed long profiles (several cm) for non- or weakly-sorbing tracers (Cl-36, Na-22), but also for many of the more strongly-sorbing radionuclides. The understanding of this unexpected feature was one of the main motivations for this modelling exercise. However, re-evaluation and revision of the data during the course of Task 9B provided evidence that the anomalous long tails at low activities for strongly sorbing tracers were artefacts due to cross-contamination during rock sample preparation. A few data points remained for Cs-137, Ba-133, Ni-63 and Cd-109, but most measurements at long distances from the tracer source (>10mm) were now below the reported detection limits.Ten different modelling teams provided results for this exercise, using different concepts and codes. The tracers that were finally considered were Na-22, Cl-36, Co-57, Ni-63, Ba-133, Cs-137, Cd-109, Ra-226 and Np-237. Three main types of models were used: i) analytical solutions to the transport-retention equations, ii) continuum-porous-medium numerical models, and iii) microstructure-based models accounting for small-scale heterogeneity (i.e. mineral grains, porosities and/or microfracture distributions) and potential centimetre-scale fractures. The modelling by the different teams led to some important conclusions, concerning for instance the presence of a disturbed zone (a few mm in thickness) next to the fracture surface and to the wall of the slim hole and the role of micro-fractures and cm-scale fractures in the transport of weakly sorbing tracers. These conclusions could be reached after the re-evaluation and revision of the experimental data (tracer profiles in the rock) and the analysis of the different sets of model results provided by the different teams.

Methodological approach to the study of the electro-hydrogen system in Northeast Asia

The article proposes a methodological approach to the development of the tools for studying the international electro-hydrogen system creation in Northeast Asia. The term "hydrogen carrier" was introduced and its definition was given. The resource, economic and technological prerequisites for the development of the unified regional infrastructure to produce, transfer, transform and utilise both electricity and "hydrogen carriers" for consumers of energy services are considered. The author points out the need for a comprehensive consideration of technological, economic, social and political factors when developing such a complex technical system, which affects the diverse actors' interests. In order to create mutual understanding and balance the stakeholders’ interests, the tool to evaluate the efficiency of such a system is necessary. The use of mathematical models is becoming one of the most vital and widespread techniques employed for this purpose. Thereby, the article deals with the structure and the development stages of a regional electro-hydrogen model for Northeast Asia. The review of models that address the issues of hydrogen technologies and renewable energy integration into energy supply systems is given. The main types of models used to describe such technical and economic systems are identified and it is concluded that the development of a two-level modelling system is necessary. The production and transport models at the upper (international) level should be the core of the proposed models system. At the lower level (the "green hydrogen carriers" production), the models of optimal resource management are required to determine the composition and parameters of the technological equipment. Step-by-step development of the modelling system is proposed. The first stage is the simplest scenario where only solar and wind energy is considered as an energy source. At this stage, it is possible to weed out inefficient technologies and identify targeted technologies and mechanisms for multilateral regional cooperation. The second stage should balance the interests of the actors and stakeholders. Here, the traditional renewable energy (biomass, hydro and pumped storage) along with carbon (thermal) and nuclear power generation, as well as other ("carbon") hydrogen technologies will become available for consideration. The final, third stage of the research tools development, will require separate accounting of "green" and "carbon" energy to consider certification mechanisms and energy pricing when building the international hydrogen system in Northeast Asia. In conclusion, the structure of the first stage production and transport model is described. This model will allow estimating the comparative effectiveness of different electric and hydrogen technologies to deliver green energy to consumers in the Northeast Asian economies.

A nameless relativ BY EXAMPLE: the degree of grammaticalization

Abstract: In the article, in relation to the nameless relativ, one of the syntactic criteria for determining the degree of grammaticalization of a significant word is considered by EXAMPLE. The relevance of the study is determined by the need to determine the place of each derived unit of the service type in the language system. The object of research is a prepositional unit BY EXAMPLE, which is included in the group of nominal relatives. The subject of our research is the degree of grammaticalization of the nameless relativ BY EXAMPLE. The purpose of the study is to determine the grammaticalization stage at which the nameless relativ is located BY EXAMPLE. The paper uses a descriptive method and a corpus method of collecting research material. The scientific novelty consists in the first described models of interaction of a prepositional-case combination, FOR example, with adjectives included in its composition. Based on the analysis of the linguistic material presented in the National Corpus of the Russian language, two main types of models have been established – with a pronominal and a non-nominal adjective. It is shown that a non-nominal adjective in such a model acts in two functions: the actant name function and the modifier function, which is typical for a significant number of similar structures with other prepositional derived units. It is revealed that personal pronominal adjectives also indicate the name of the actor. It is determined that demonstrative pronominal adjectives do not have named functions. Their entry into the model indicates the absence of a service function in the combination FOR EXAMPLE. The article concludes that the nameless relativ, by example, is only at the initial stage of grammaticalization.

Studying the practices of implementing a multilingual model of multicultural education in the Russian Federation

Introduction. The article discusses the practices of implementing a multilingual model of multicultural education in the Russian Federation. The Russian Federation is a multinational and linguistically diverse country. The official language of the country is Russian; 37 state languages are spoken in the republics of the Russian Federation; more than 15 languages have an official status. For a number of regions of the country, the model of multilingual learning is extremely relevant. The purpose of the article is to study the practices of implementing a multilingual model of multicultural education in the territory of the Russian Federation and to conduct their comparative analysis. Materials and Methods. Within the framework of the study, the analysis of legislative documents regulating the processes of multicultural and multilingual education in the Republic of North Ossetia-Alania, Kabardino-Balkar Republic, Chechen Republic, Republic of Sakha (Yakutia), Republic of Tatarstan, Chuvash Republic, Republic of Bashkortostan (state programs, concepts, regulations, etc.) was carried out. Data gathering included round-table discussions and interviews with the representatives of academic and teaching communities of the regions; analyses of curricula, syllabi and teaching materials on language disciplines; lesson observations; questionnaires and language assessment of primary (4th grade) and secondary schoolchildren (8th grade) in foreign and native languages; analysis of academic performance and attainment (e.g. the results of the All-Russian Olympiad of schoolchildren in Russian and Foreign Languages, national assessment, state final certification, and final national examinations). Results. The research team of Bashkir State Pedagogical University named after M. Akmulla, in accordance with the state task in the field of science of the Ministry of Education of the Russian Federation, has been implementing a research investigation ‘Comparative analysis of the practices of implementing a multilingual model of multicultural education (with the main focus on the Republics of Bashkortostan, Tatarstan, North Ossetia-Alania, Sakha (Yakutia), etc.)’ since 2021. The authors have determined the main types of models of multilingual education implemented in the studied regions. In particular, the models presented in the Republic of North Ossetia-Alania, the Republic of Tatarstan and the Republic of Sakha (Yakutia) are reported to be the most developed as they have been implemented for several years. The findings in this study contribute to a greater understanding of the specifics of multilingual education in Russia and the study makes a theoretical contribution to multilingual education in general. Conclusions. The article concludes that currently there is no a single coordinated model for multilingual education in Russian schools. The development of a multilingual model of multicultural education is primarily aimed at preserving and further developing the native languages in the subjects of the Russian Federation, remaining one of the most important tasks not only in terms of solving narrow ethno-cultural problems, but also in the context of preserving the natural multicultural basis of the multinational Russian state.

A unified physiological framework of transitions between seizures, sustained ictal activity and depolarization block at the single neuron level

The majority of seizures recorded in humans and experimental animal models can be described by a generic phenomenological mathematical model, the Epileptor. In this model, seizure-like events (SLEs) are driven by a slow variable and occur via saddle node (SN) and homoclinic bifurcations at seizure onset and offset, respectively. Here we investigated SLEs at the single cell level using a biophysically relevant neuron model including a slow/fast system of four equations. The two equations for the slow subsystem describe ion concentration variations and the two equations of the fast subsystem delineate the electrophysiological activities of the neuron. Using extracellular K+ as a slow variable, we report that SLEs with SN/homoclinic bifurcations can readily occur at the single cell level when extracellular K+ reaches a critical value. In patients and experimental models, seizures can also evolve into sustained ictal activity (SIA) and depolarization block (DB), activities which are also parts of the dynamic repertoire of the Epileptor. Increasing extracellular concentration of K+ in the model to values found during experimental status epilepticus and DB, we show that SIA and DB can also occur at the single cell level. Thus, seizures, SIA, and DB, which have been first identified as network events, can exist in a unified framework of a biophysical model at the single neuron level and exhibit similar dynamics as observed in the Epileptor.Author Summary: Epilepsy is a neurological disorder characterized by the occurrence of seizures. Seizures have been characterized in patients in experimental models at both macroscopic and microscopic scales using electrophysiological recordings. Experimental works allowed the establishment of a detailed taxonomy of seizures, which can be described by mathematical models. We can distinguish two main types of models. Phenomenological (generic) models have few parameters and variables and permit detailed dynamical studies often capturing a majority of activities observed in experimental conditions. But they also have abstract parameters, making biological interpretation difficult. Biophysical models, on the other hand, use a large number of variables and parameters due to the complexity of the biological systems they represent. Because of the multiplicity of solutions, it is difficult to extract general dynamical rules. In the present work, we integrate both approaches and reduce a detailed biophysical model to sufficiently low-dimensional equations, and thus maintaining the advantages of a generic model. We propose, at the single cell level, a unified framework of different pathological activities that are seizures, depolarization block, and sustained ictal activity.

Darwinian Approaches for Cancer Treatment: Benefits of Mathematical Modeling.

Simple SummaryMany cancers develop resistance and become unresponsive to traditional treatment strategies. In this review we highlight how mathematical models can aid the implementation of alternative treatment strategies that take into account the ecology and evolution of tumors in order to circumvent the emergence of resistance. We review some of the mathematical models that can be used and that have contributed to showing that Darwinian approaches for cancer treatment, like adaptive therapy, are promising anti-cancer treatment strategies.One of the major problems of traditional anti-cancer treatments is that they lead to the emergence of treatment-resistant cells, which results in treatment failure. To avoid or delay this phenomenon, it is relevant to take into account the eco-evolutionary dynamics of tumors. Designing evolution-based treatment strategies may help overcoming the problem of drug resistance. In particular, a promising candidate is adaptive therapy, a containment strategy which adjusts treatment cycles to the evolution of the tumors in order to keep the population of treatment-resistant cells under control. Mathematical modeling is a crucial tool to understand the dynamics of cancer in response to treatments, and to make predictions about the outcomes of these treatments. In this review, we highlight the benefits of in silico modeling to design adaptive therapy strategies, and to assess whether they could effectively improve treatment outcomes. Specifically, we review how two main types of models (i.e., mathematical models based on Lotka–Volterra equations and agent-based models) have been used to model tumor dynamics in response to adaptive therapy. We give examples of the advances they permitted in the field of adaptive therapy and discuss about how these models can be integrated in experimental approaches and clinical trial design.

Structural model of a cloud-based learning environment for bachelors in software engineering

The article summarizes the essence of the category "model", presents the main types of models used in pedagogical research: structural, functional, structural-functional models. The basic requirements for the construction of these types of models are also given. The experience in building a model and designing a cloud-based learning environment of educational institutions (both higher and secondary) is analyzed. A structural model of a cloud-based learning environment for bachelors in software engineering is presented. Each component of the cloud-based learning environment model for bachelors in software engineering is described: target, management, organizational, content and methodical, communication, technological and effective. The model of interaction of participants of the educational process in the cloud-based learning environment is developed. Forms, methods, and tools (both traditional and cloud-based) of content and methodological components of the cloud-based learning environment's structural model that can be implemented in this cloud-based LMS are described. Forms of an educational activity (classes, practical training, independent work, control measures, as well as research work of students) are considered. The types of lectures that can be conducted in a cloud-based learning support system are described: lecture-conversation, lecture-discussion, video lecture, lecture-consultation, and lecture-presentation. The types of practical training offered in the cloud-based learning support system are described: laboratory work, workshop, seminar, and webinar. Different types of independent work and assessment are considered. The research work of students as a form of educational activity provided by the curriculum of bachelors in software engineering is singled out. The main teaching methods that can be implemented using a cloud-based LMS to support the training of bachelors in software engineering are considered. It is generalized that the cloud-based learning environment should solve all the main tasks facing higher education institutions.

АНАЛІЗ УШКОДЖЕНОСТІ МАТЕРІАЛУ КОНСТРУКЦІЙ

The ability of materials to retain the required set of properties under the action of operational loads on the structure is determined by the structural changes that occur under such loads. From the first days of operation, under the influence of force factors, the environment and time, the strength and deformation properties of structures of buildings and structures change. The solution to the main task of construction science - reducing material consumption in construction, is inextricably linked with the need for constant study and refinement of the strength and deformation characteristics of building materials and structures, as well as a change in their bearing capacity over time and an assessment of the working capacity (resource) reserve when setting an external power load. Based on the fundamental position that under the action of a load, a deformation process occurs in the construction material, which is accompanied by irreversible processes of their appearance, development and accumulation of damage to the structure of the material, and, as a result, leads to destruction, we come to the conclusion that it is necessary to carefully study the strength of wooden designs taking into account this phenomenon. There is a need to comprehensively study the issues of damage accumulation in wooden structures under the action of loads and the related processes of changing the cross-sectional area and bearing capacity, to use the research results when calculating structures. This makes it possible to reduce material consumption and make the sections of wooden structures more economical and avoid excessive safety margins. Therefore, an important manifestation is the fixation of cracks and internal interfaces, which allows one to quantify the integral damage of the structure material to predict their safe functioning. The authors considered analytical dependences for the description of disseminated injuries that follow from physical considerations or are constructed from some mechanical models of the process of long-term damage. Three main types of models have been identified: force, deformation and energy. Experimental studies of normal stress diagrams make it possible to visually record the formation of folds in the compressed zone, as well as calculate the value of the instantaneous elastic and viscoelastic components of total deformation. A measure of the accumulation of damage in a material is damage. In this work, the damage was calculated based on the known specific parameters of the material: deflections, relative deformations and changes in the number of acoustic emission signals. The graphs of the dependence of damage on the load were built: - on the development of deflections; - on the development of fibrous deformations; - on the development of deflections and acoustic emission (relative load); - on the development of fibrous deformations (relative load); This scientific work is a logical continuation of previous studies of damage to wooden structures. The article presents the results of experimental studies of the strength, deformability of wooden beams under the influence of a static load. The direction of improving the methodology for designing wooden structures and determining the residual resource has not been reflected in the technical literature. Therefore, it is necessary to conduct a comprehensive study of them.

Modern experience in the use of organizational & economic mechanism of regulation of the process of fundamental scientific knowledge’ production

The subject of the research is cross-country comparisons of models of organizational and economic mechanism of regulation (OEMR) of processes of production of fundamental scientific knowledge (FSK) during the organization of basic scientific research (FSR) by academic institutions. The ultimate goal of the development of OEMR and the task of conducting FSR is formulated. The hypothesis about the possibility of effective implementation of OEMR FSR in the case of clear definition of subjects and forms of regulation is substantiated. The thesis on the expediency of structuring OEMR FSR with the separation of levels of systematization of scientific knowledge as an object of regulation, conceptual components, subject content of FSK subsystems, elements of the FSK formation cycle in the process of solving partial cognitive problems of fundamental scientific theories (FNT), functional levels principles and criteria for ensuring the effectiveness of non-monotonic abductive FSR, distinguishing tools for providing analytical and regulatory functions.
 The research method is to generalize the features of national models of public regulation of FSR, which differ in proportions and combination of methods of direct administration and create conditions for independent choice of subjects of directions and options of R&D under the influence of dynamic updating of axiological concept of FSR. There are methods of using power competencies to form and use basic research competencies of FSR subjects in the field of FSR production – direct administrative influence, formal-mechanistic solidarity of subjects within the functioning of academic research networks, external value orientation and motivation of FSR subjects. The list of methods of stimulating innovative renewal of practical and transformative competencies in the field of FSK functioning includes methods of indirect regulatory influence, contractual solidarity of FSR subjects within the functioning of voluntary/temporary professional research networks, internal value and identification orientation of FSR subjects, global standards of practical and transformative competencies of FSR subjects in the field of FSK formation.
 The result of the study is to identify the main types of models with a detailed description of the practical principles of the implementation of FSR in the countries that represent them. The difference in the potential of FSR implementation depends on the ability of national institutions to organize the processes of conducting cyclical program research in order to increase the background design knowledge of the most universal nature.

COVID-19 and computation for policy

Governments across the world are formulating and implementing medical, social, economic and other policies to manage the COVID-19 pandemic and protect their citizens. Many governments claim that their policies follow the best available scientific advice. Much of that advice comes from computational modeling. Two of the main types of model are presented: the SIR (Susceptible, Infected, Recovered) model developed by Kermack and McKendrick in the 1920s and the more recent Agent Based Models. The SIR model gives a good intuition of how epidemics spread; including how mass vaccination can contain them. It is less useful than Agent Based Modeling for investigating the effects of policies such as social distancing, self-isolation, wearing facemasks, and test-trace-isolate. Politicians and the public have been perplexed to observe the lack of consensus in the scientific community and there being no single 'best science' to follow. The outcome of computational models depends on the assumptions made and the data used. Different assumptions will lead to different computational outcomes, especially when the available data are so poor. This leads some commentators to argue that the models are wrong and dangerous. Some may be, but computational modeling is one of the few ways available to explore and try to understand the space of possible futures. This lack of certainty means that computational modeling must be seen as just one of many inputs into the political decision making process. Politicians must balance all the competing inputs and make timely decisions based on their conclusions---be they right or wrong. In the same way that democracy is the least worst form of government, computational modeling may be the least worst way of trying to understand the future for policy making.

Process-based models outcompete correlative models in projecting spring phenology of trees in a future warmer climate

Many phenology models have been developed to explain historical trends in plant phenology and to forecast future ones. Two main types of model can be distinguished: correlative models, that statistically relate descriptors of climate to the date of occurrence of a phenological event, and process-based models that build upon explicit causal relationships determined experimentally. While process-based models are believed to provide more robust projections in novel conditions, it is still unclear whether this assertion always holds true and why. In addition, the efficiency and robustness of the two model categories have rarely been compared. Here we aimed at comparing the efficiency and the robustness of correlative and process-based phenology models with contrasting levels of complexity in both historical and future climatic conditions. Models were calibrated, validated and compared using budburst dates of five tree species across the French Alps collected during 8 years by a citizen-science program. Process-based models were less efficient, yet more robust than correlative models, even when their parameter estimates relied entirely on inverse modeling, i.e. parameter values estimated using observed budburst dates and optimization algorithms. Their robustness further slightly increased when their parameter estimates relied on forward estimation, i.e. parameter values measured experimentally. Our results therefore suggest that the robustness of process-based models comes both from the fact that they describe causal relationships and the fact that their parameters can be directly measured. Process-based models projected a reduction in the phenological cline along the elevation gradient for all species by the end of the 21st century. This was due to a delaying effect of winter warming at low elevation where conditions will move away from optimal chilling conditions that break bud dormancy vs an advancing effect of spring warming at high elevation where optimal chilling conditions for dormancy release will persist even under the most pessimistic emissions scenario RCP 8.5. These results advocate for increasing efforts in developing process-based phenology models as well as forward modelling, in order to provide accurate projections in future climatic conditions.

СОВРЕМЕННЫЕ МОДЕЛИ АДАПТАЦИИ НАСЕЛЕНИЯ К ДИНАМИЧНО МЕНЯЮЩИМСЯ СОЦИАЛЬНО-ЭКОНОМИЧЕСКИМ УСЛОВИЯМ ЖИЗНИ

In recent years, living conditions of a population have changed rapidly due to complex social, economic, cultural, political and other processes. This naturally leads not only to a transformation of the system of values, motivation, worldview, but also an entire way of life. High rates of these changes simultaneously led a delegation given, on the one hand, a diversity of forms of response behavior, from the other – their gradual integration into the socio-economic relations in a search result models of individual and collective adaptation to a new dynamic environment, characterized by high uncertainty and heterogeneity. Thus, the purpose of this study is to identify and describe the main models of population adaptation on an interdisciplinary basis, not limited to an analysis of complex processes within a single field of knowledge. In this regard, the task is to find a way to harmonize (coordinate) different points of view on a nature of a single phenomenon. The object of our research is a variety of adaptation processes of a population to dynamically changing conditions of its life. At the same time, the subject should be a wide range of different types of interactions between a population and an external environment, as well as a population “within itself”, as part of the model of its adaptation to changing conditions. To achieve the goal and solve problems, a set of methods that complement each other is used, namely: theoretical analysis and synthesis, systematization and comparative analysis. As a result, it was found that population adaptation is a rather complex phenomenon, the study of which goes far beyond the formal framework of any one field of knowledge, being at their intersection, which requires the search for new approaches that allow integrating explanations of the nature of phenomena that are currently interpreted within their paradigms. The article presents the main types of models of population adaptation to dynamically changing socio-economic conditions of life, their features, identity and differences, as well as areas of application

Моделирование в современной педагогике

The paper analyses modeling problem in modern education science. The relevance of the modeling problem is due to the growing interest in modeling in education science, as well as the great modeling potential in solving pedagogical problems. The main problems that modern teachers deal with are identified, and the classification of models is given. The concepts of modeling in the interdisciplinary field and in the psychological and education sciences are characterized. Various definitions of the model are analysed, the main types of models in modern pedagogical research are proposed. The interdisciplinary nature of modeling is substantiated. The features of modeling in pedagogy are reviewed. The basic requirements for pedagogical models are formulated. The novelty of the proposed material lies in the substantiation of the interdisciplinary nature of modeling, as well as in the formulation of requirements for pedagogical models.

Carbonate acidizing: A mechanistic model for wormhole growth in linear and radial flow

Highly conductive fluid flow paths, known as wormholes, are formed when acids are injected in carbonate reservoirs during a stimulation treatment. In matrix acidizing treatments, these wormholes are desired whereas in acid fracturing treatments, they are undesirable because they reduce efficiency of the process. Two main types of models are available in the literature for wormhole growth. Semi-empirical models are computationally fast; however, they do not scale well to core dimensions or to radial flow. Numerical simulation models represent the physics of the individual processes well; however, they are computationally intensive and impractical to use on a field scale.To address the shortcomings of these models, a computationally fast mechanistic model is developed for wormhole growth. The model scales well with flow rate and core dimensions. It hence allows scale-up from linear laboratory core flow experiments to field scenarios of radial flow. Accurate scaling with core dimension and with injection rate in linear flow is a necessary precondition for a model to be considered for scale-up to radial flow where both cross-sectional area to flow and the fluid Darcy velocity change as the wormholes grow. Previous computationally fast models did not satisfy this precondition and therefore are not suitable for scaleup to radial flow.The model is validated against more than 50 published and internal sets of linear core-flood experiments on limestone and dolomite cores treated with HCl and emulsified acids. The validation dataset covers a wide range of acid concentrations, temperatures, rock types and core dimensions. The modeling equations extend to radial flow based on the change in the domain area with wormhole progression. The radial model was tested against 10 published radial flow experiments and a reasonable match was obtained. The model predictions were also tested against field results and again a good match was obtained.

Innovative Analysis of Models for Evaluating the Probability of Enterprises Bankruptcy

The article is devoted to the relevant topic which is assessment of the insolvency (bankruptcy) of enterprises. The instability of a complex socioeconomic system is intensifying in the market economy, which is difficult to fully study and understand. Modern business is being run in a highly competitive environment. Adequate decision-making requires a deep, comprehensive assessment of the situation and a reliable forecast of events. A firm that has managed to correctly forecast the situation receives more profit than a firm that abstained from forecasting. The firm that made the wrong forecast loses the most. The main types of models for assessment of the bankruptcy probability for enterprises and the factors influencing them in the course of making decisions have been considered in this article, and the bankruptcy probability for Megafon PJSC based on various models has been studied. A comparative analysis of the models for assessment of the bankruptcy probability for enterprises has been conducted. The methods of cognition, retrospective and documentary analysis, as well as synthesis, generalization, and systematization were used in the article.

Models for Assessing the Bankruptcy Probability for Enterprises

The article is devoted to the relevant topic which is assessment of the insolvency (bankruptcy) of enterprises. The instability of a complex socioeconomic system is intensifying in the market economy, which is difficult to fully study and understand. Modern business is being run in a highly competitive environment. Adequate decision-making requires a deep, comprehensive assessment of the situation and a reliable forecast of events. A firm that has managed to correctly forecast the situation receives more profit than a firm that abstained from forecasting. The firm that made the wrong forecast loses the most. The main types of models for assessment of the bankruptcy probability for enterprises and the factors influencing them in the course of making decisions have been considered in this article, and the bankruptcy probability for Megafon PJSC based on various models has been studied. A comparative analysis of the models for assessment of the bankruptcy probability for enterprises has been conducted. The methods of cognition, retrospective and documentary analysis, as well as synthesis, generalization, and systematization were used in the article.