Colloquiam: Documents published in 2022

Budgetary Sustainability: State in Russia

Евгений Семенов — Wed, 14 Sep 2022 15:50:03 +0200

Fiscal sustainability presupposes, on the one hand, balanced development (sustainability in the long term), and on the other, sustainability, that is, short-term resilience to external shocks. Debt sustainability provides the conditions for countercyclical fiscal policy.

TRANSFORMATION OF LEGAL AND ECONOMIC CONSEQUENCES OF THE APPLICATION OF INTERNATIONAL TAX AGREEMENTS IN THE CONDITIONS OF THE FORMATION OF THE DIGITAL ECONOMY

Евгений Семенов — Wed, 14 Sep 2022 13:55:03 +0200

The work is devoted to the prospects of transformation of bilateral tax treaties in digital conditions. To address this question, the authors studied the prerequisites for the transformation of tax systems in an environment of increasing use of digital technologies, and identified key tax challenges.

Development of Approaches to Improving the Mechanism of Taxation of Personal Income in the Russian Federation in the Context of Digitalization of Tax Administration

Евгений Семенов — Wed, 14 Sep 2022 13:49:03 +0200

The use of digital technologies in tax administration is a promising way to develop the tax system itself and a necessary condition for the transition to a qualitatively new level of implementation of taxpayers' rights. By increasing the transparency of operations in the economy and reducing the cost of meeting the tax legislation requirements, digitalization brings strong advantages that make us to take a different look at the longstanding rules of calculating personal income tax. In this regard some significant issues of tax fairness and progressivity rise.

Assessment of the Impact of Regional Norms of Tax Payments to Local Budgets on the Taxable Base

Евгений Семенов — Wed, 14 Sep 2022 13:44:03 +0200

The paper considers the impact of regional tax transfers to municipal budgets on the taxable base on a sample of 72 Russian regions for the period 2011–2018. The results of the assessment show that the transfer of the tax applied under the simplified taxation system and personal income tax has a positive effect in poor regions. The transfer of corporate income tax has a positive effect in rich regions. No significant results were obtained in regard to corporate property tax.

Forecasting Parameters of Socio-Economic, Budget and Financial Development of the Russian Federation and Management of Key Macroeconomic Risks in the Medium Term

Евгений Семенов — Wed, 14 Sep 2022 13:38:02 +0200

The object of the research was socio-economic and financial-budgetary relations, as well as macroeconomic risks.

Pareto-Improving Carbon-Risk Taxation

Евгений Семенов — Wed, 14 Sep 2022 13:23:03 +0200

Anthropogenic climate change produces two conceptually distinct negative economic externalities. The first is an expected path of climate damage. The second, which is this paper's focus, is an expected path of economic risk. To isolate the climate-risk problem, we consider mean-zero, symmetric shocks in our 12-period, overlapping generations model. These shocks impact dirty energy usage (carbon emissions), the relationship between carbon concentration and temperature, and the connection between temperature and damages. Our model exhibits a de minimis climate problem absent its shocks. But due to non-linearities, symmetric shocks deliver negatively skewed impacts, including the potential for climate disasters. As we show, Pareto-improving carbon taxation can dramatically lower climate risk, in general, and disaster risk, in particular. The associated climate-risk tax, which is focused exclusively on limiting climate risk, can be as large or larger than the carbon average-damage tax, which is focused exclusively on limiting average damage.

Long-run relationship between real consumption and real income in the Russian Federation: An ARDL bounds testing approach

Евгений Семенов — Wed, 14 Sep 2022 12:01:04 +0200

This paper considers an application of the ARDL model and bounds testing approach to the analysis of the long-run relationship between household consumption and aggregate income. We have explored the presence of a long-run relationship between real household consumption and indicators characterizing real income, such as: real gross domestic product (GDP), real gross domestic income (GDI), and GDP at constant household consumption prices. We provide statistical evidence of the lack of a long-run relationship in the first and second cases and its presence in the third case. We have concluded that the nominal GDP deflated by the price index of aggregated consumption is the most applicable indicator for describing the dynamics of real consumption in the Russian Federation.

Comparative analysis of the forecasting models for Russia’s GDP under the structural breaks

Евгений Семенов — Wed, 14 Sep 2022 11:56:03 +0200

In this paper we compare two types of models for forecasting Russia’s GDP under the structural breaks. We consider models that allow breaks in a deterministic trend, in which the dates of structural breaks set exogenously, and more flexible class of models – with a stochastic trend. We show that models with a stochastic trend demonstrate the best result in GDP growth rates forecasting for a year ahead. For shorter horizons, the best forecasting model is the error correction model with a break in the deterministic trend in the GDP level.

Predictability of Preliminary Estimates of Macroeconomic Indicators: An Overview of Approaches

Евгений Семенов — Wed, 14 Sep 2022 11:41:02 +0200

This paper provides an overview of methods for testing the predictability of macroeconomic indicators based on real-time data revisions. Various approaches to their forecasting are considered and their properties are discussed.

Approaches to Analysis of Resource Allocation in the Russian Economy and Its Relationship With Productivity

Евгений Семенов — Wed, 14 Sep 2022 11:36:02 +0200

The paper proposes an approach to assessing the efficiency of resource allocation in the Russian economy.

Prospects for Accounting and Measuring the Digital Economy Based on National Accounts Applications

Евгений Семенов — Wed, 14 Sep 2022 11:29:02 +0200

In this paper we estimate the degree of producer price rigidity in the Russian economy and identify the response of various industries to monetary policy shocks, taking into account the heterogeneity of the rigidity parameter. The first part of the paper reviews theoretical approaches to modeling producer price rigidity, including models in which price revisions depend either only on time, or only on the state of the economy, as well as a hybrid pricing model.

Modeling and Forecasting Production Indices Using Artificial Neural Networks, Taking Into Account Intersectoral Relationships and Comparing the Predictive Qualities of Various Architectures

Евгений Семенов — Wed, 14 Sep 2022 11:23:03 +0200

This paper analyzes the possibilities of using convolutional and recurrent neural networks to predict the indices of industrial production of the Russian economy. Since the indices are asymmetric in periods of growth and decline, it was hypothesized that nonlinear methods will improve the quality of the forecast relative to linear ones.

Main Structural Shifts in the Russian Economy: The Potential for Economic Growth and Social Modernization

Евгений Семенов — Wed, 14 Sep 2022 11:15:03 +0200

This paper analyzes the main structural shifts in the Russian economy since 2014. The question of how the 2020 crisis will affect the further economic development of the country is investigated.

Estimation of Actual Final Consumption and Household Assets Based on a Structural Approach in the Russian Federation

Евгений Семенов — Wed, 14 Sep 2022 11:08:02 +0200

The subject of the research is actual problems of methodology and practice of measuring the population’s standard of living in the statistics of the Russian Federation, the adequate solution of which allows improving the quality and provide a greater analytical orientation of the developed system of indicators.

Assessment of the Influence of the Macroprudential Policy of the Central Bank of the Russian Federation on Economic Development

Евгений Семенов — Wed, 14 Sep 2022 11:01:04 +0200

The global financial crisis of 2008-09 patently demonstrated that ensuring price stability by central banks does not guarantee the achievement of financial stability and is not a sufficient condition for it. It also showed how destructive the result of accumulating imbalances in the financial sector can be.

Neutral Percentage Rate: Analysis and Evaluation for the Russian Economy

Евгений Семенов — Wed, 14 Sep 2022 10:54:02 +0200

The neutral interest rate is one of the basic components of a large number of macroeconomic and, in particular, monetary models. Central banks take estimates of the level of neutral interest rate into account when conducting monetary policy to determine its degree of rigidity / softness.

Impact of Monetary Policy on Investment and Issue in Industries With Different Price Rigidity

Евгений Семенов — Wed, 14 Sep 2022 10:48:02 +0200

Analysis of the Behavior of Banks and Companies in the Conditions of Exchange Volatility in Russia

Евгений Семенов — Wed, 14 Sep 2022 10:43:02 +0200

In this paper we study the mechanisms and estimate the influence of exchange rate volatility on key performance indicators of financial and non-financial companies. Exchange rate volatility, being both a consequence and an indicator of uncertainty, accompanied by risks to macroeconomic stability and increased volatility of other macroeconomic indicators, has a significant impact on the performance of Russian banks and companies.

Development of a Model Toolkit for Forecasting Gross Regional Product and Key Socio-Economic Indicators of Regional Development

Евгений Семенов — Tue, 13 Sep 2022 17:03:02 +0200

The object of the study was the Russian economy and the types of activities of individual regions. The main purpose of the study was to build a model for forecasting the gross regional product (GRP) by the production method.

Development of a Methodology for Balancing the Medium – and Long-Term Forecasts of Social – Economic Development of the Russian Federation

Евгений Семенов — Tue, 13 Sep 2022 15:55:03 +0200

The object of the study was the economy of the Russian Federation, institutional agents (the state, non-financial enterprises, the Central Bank of the Russian Federation, the outside world, the population, the banking system), individual sectors of the economy.

Total Factor Productivity in Russia: The Impact of Economic and Geographical Conditions and Human Capital

Евгений Семенов — Tue, 13 Sep 2022 11:06:04 +0200

Within the framework of this study, the stability of the aggregate factor productivity (TFP) in Russia to the estimation method was assessed. Approaches to assessing TFP were systematized, an approach was developed for analyzing TFP, taking into account the economic and geographical characteristics and the role of human capital.

Stabilizing a Josephson Junction Array Memory around an unstable equilibrium: A control approach using a first order state model

JORGE LOPEZ LOPEZ — Fri, 09 Sep 2022 05:16:13 +0200

In this paper we consider a system of three nonlinear ordinary differential equations that model a three Josephson Junctions Array (JJA). Our goal is to stabilize the system around an unstable equilibrium employing an optimal control approach. We first define the cost functional and calculate its differential by using perturbation analysis and variational calculus. For the computational solution of the optimality system we consider a conjugate gradient algorithm for quadratic functionals in Hilbert spaces, combined with a finite difference discretization of the involucrated differential equations.

Study of Relationship of Psychobiographic Features With Individual – Psychological and Personal Characteristics of Heads of Public Administration

Евгений Семенов — Thu, 08 Sep 2022 16:23:03 +0200

This research work is devoted to the problem of identifying biographical factors and predictors of the development of managerial potential and managerial readiness

Development of a Model of a Unified Multi-Level Personnel Reserve of the Public Administration System

Евгений Семенов — Thu, 08 Sep 2022 16:21:03 +0200

The research work is devoted to the analysis of the practice of forming personnel reserves, determining the conditions and factors affecting the level of maturity of the reserve as an integrated personnel technology, as well as the possibilities of forming a single multi-level reserve of the public administration system.

Development of Technology of Personal and Professional Diagnostics and Assessment of Management Potential Using Models of Forecasting Analytics

Евгений Семенов — Thu, 08 Sep 2022 16:16:02 +0200

The purpose of the study is to improve the accuracy of forecasting the assessment of the management potential of current and potential leaders of the public administration system based on the use of a holistic diagnostic complex developed on the basis of a general methodology and the construction of predictive analytical models.

Development of a Concept for Forming a Unified Talent Management System in Russia

Евгений Семенов — Thu, 08 Sep 2022 16:11:02 +0200

The main result of this research work is the creation of a personality-oriented model of working with talents in the public administration system, which today meets the modern requirements for the development of national human capital.

Use of the Possibilities of Mobile Digital Technologies in the Assessment of Personal-Professional and Management Resources

Евгений Семенов — Thu, 08 Sep 2022 16:08:02 +0200

As part of the research work, the modern experience of using digital technologies in the field of recruiting and evaluating personnel was analyzed, the most popular approaches to assessing employees and managers were compared, an alternative "worldview" approach to analyzing the value-semantic sphere of the leader was substantiated.

State and Prospects for Development of the Unified Information System for Managing the Staff of the State Civil Service of the Russian Federation

Евгений Семенов — Thu, 08 Sep 2022 15:43:02 +0200

This study is devoted to the study, analysis of the practice of use, description of the state and development prospects of the federal state information system "Unified information system for managing the personnel of the state civil service of the Russian Federation", the development of proposals for improving the module "Professional development", the construction of a management algorithm for the Unified system in terms of professional development of state civil servants of the Russian Federation.

Improving the Activities of Bodies and Organizations of the Public Sphere in Russia through the Implementation of the European Model of Quality Improvement

Евгений Семенов — Thu, 08 Sep 2022 15:38:02 +0200

This study is devoted to the study and analysis of the experience and problems of implementation of one of the modern models of quality management in the field of public administration - the European model for improving the performance of public sector organizations through the self-assessment of the Common Assessment Framework, CAF (hereinafter - CAF).

Modern Approaches to Forming Legal Support for Reforming Control and Supervision Activities

Евгений Семенов — Thu, 08 Sep 2022 15:17:02 +0200

One of the main tasks of the state at the present stage is the development of a clear concept of control and discordant activity, ensuring sustainable socio-economic development of the state, creating conditions for the unhindered development of entrepreneurial and other economic activities, as well as ensuring the safe life of a person, society, state in conditions, excluding (minimizing) the possibility of causing harm by the processes and results of entrepreneurial and other economic activities. Successful reform of control and supervisory activities is impossible without the proper design of its legal support.

Influence of Regulatory Rigidity of the Regulatory and Legal Framework on Indicators of Socio-Economic Dynamics

Евгений Семенов — Thu, 08 Sep 2022 15:07:02 +0200

The main purpose of the research is to develop and assess an econometric model of the influence of the regulatory framework rigidity on indicators of socio-economic dynamics, namely, on poverty indicators in the regions of Russia.

Economic Evaluation of Living Cost and Damage as a Basis for Risk-Based Regulation

Евгений Семенов — Thu, 08 Sep 2022 14:54:02 +0200

The object of the present research is the economic value of life as the basis for making decisions when changing approaches to government regulation of various areas.

Development of Scientific and Methodological Approaches to Identifying the Actual Boundaries of Agglomerations in Russia, Taking into Account the Spatial Distribution of Economic Activity

Евгений Семенов — Thu, 08 Sep 2022 14:51:03 +0200

Urban agglomerations are the core of the country's economic development and sources of Russia's competitiveness in the global economy (according to various estimates, only Moscow agglomeration generates about 25% of the country's GDP)

Practice of Application of Regulatory Guillotine to Reduce the Load on Bodies Carrying out Control and Supervision Activities

Евгений Семенов — Thu, 08 Sep 2022 14:44:03 +0200

The object of the research is the reform of the control and supervision bodies, elements and the control and supervision process as a whole in different areas.

Monitoring the Achievement of National Goals of Decree No. 204 Using International Experience and the System of Sustainable Development Indicators

Евгений Семенов — Thu, 08 Sep 2022 14:41:02 +0200

National development goals trajectories and national projects implementation indicator system assessment in terms of their international comparability is an important task to improve the effectiveness of monitoring these parameters.

Mechanisms for Planning, Organization and Accounting of Measures for Professional Development of Public Civil Employees

Евгений Семенов — Thu, 08 Sep 2022 14:36:02 +0200

This report presents the results of a study on the planning, organization and accounting of activities for the professional development of civil servants in the context of a promising competency model

Theoretical and Empirical Approaches to Assessing Administrative Reform Measures on the State of the Public Administration System

Евгений Семенов — Thu, 08 Sep 2022 14:30:02 +0200

The purpose of the report is to provide recommendations on various aspects of the development of administrative reform - strategic planning, implementation of projects at the national level, results-based management, the use of remote methods of performance.

A unified non-linear energy dissipation-based plastic-damage model for cyclic loading

Eugenio Oñate — Thu, 08 Sep 2022 10:01:29 +0200

A new energy-dissipation-based rate-independent constitutive law within the framework of elastoplasticity coupled with damage is proposed. With this methodology, the inelastic strains and the stiffness degradation exhibited by quasi-brittle materials under monotonic or cyclic loading conditions are taken into account. The proposed constitutive model is able to capture micro-cracks closure-reopening effects due to load reversal. A wide variety of hardening/softening laws on the stress–strain relationship are described and considered for the novel normalized plastic-damage energy dissipation internal variable. This normalized internal variable allows the model to be independent on the sign of the load and dissipate different fracture energies (tensile, compressive and potentially shear) in a natural way. Several numerical examples are presented in order to ensure the efficiency and validity of the proposed model for simulating the non-linear behaviour of quasi-brittle materials under monotonic and cyclic loading. Some numerical aspects of the implemented algorithm and the return mapping procedure are also described in detail and discussed.

Public Governance Quality Indicators

Евгений Семенов — Wed, 07 Sep 2022 16:03:03 +0200

The scientific report analyzes the main foreign and Russian approaches to assessing the quality of public administration. On the basis of the analysis, the key parameters of the quality of public administration were substantiated and a system of indicators for their measurement and evaluation was developed. Brief results of approbation of the developed system are presented.

Development of Proposals to Eliminate System Legal Restrictions Digitalization of Public Administration

Евгений Семенов — Wed, 07 Sep 2022 15:57:02 +0200

Within the framework of this work, the legal regulation of the introduction of digital technologies (digitalization) of public administration is considered.

Legal Risks of Using Distributed Register Technology in Public Administration

Евгений Семенов — Wed, 07 Sep 2022 15:55:03 +0200

Within the framework of this work, the actual relations associated with the application of distributed ledger technology (TRR) in public administration and the potential of their legal regulation have been analyzed. The legal risks of using TPP in public administration were identified and systematized, a classification of legal risks when using TPP, primarily in the form of a blockchain, in public administration was proposed. Proposals are formulated to overcome legal risks when using TRP in public administration.

Brief Results of Sociological Survey of Citizens on Assessment of Performance and Efficiency of State Control

Евгений Семенов — Wed, 07 Sep 2022 15:51:03 +0200

The scientific report provides brief results of a representative sociological survey of citizens conducted by RANEPA in 2020, which allows to identify an assessment of the effectiveness and efficiency of state control (supervision) from the position of ultimate beneficiaries.

Assessment of the Performance and Efficiency of the Digitalization of Public Administration

Евгений Семенов — Wed, 07 Sep 2022 15:48:02 +0200

The scientific report presents the results of assessing the effectiveness and efficiency of digitalization of Russian public administration at the federal and regional levels. The main effects of the digitalization of public administration for citizens, business and the state are revealed.

Assessment of Control and Supervision Activities of the State From a Business Position: Brief Result

Евгений Семенов — Wed, 07 Sep 2022 15:09:02 +0200

The scientific report presents the brief results of a representative sociological study of representatives of private business entities, conducted by RANEPA in 2020, aimed at assessing the effectiveness and efficiency of state control and supervisory activities from the standpoint of business.

Foreign Experience in Taxation, Control and Supervision in the Sphere of Import Electronic Services

Евгений Семенов — Wed, 07 Sep 2022 15:05:02 +0200

The presented work analyzes foreign experience in the field of both indirect and direct taxation for 2020.The situation with the position of countries on the introduction of a new tax, the possible adaptation of income tax by introducing the concept of a significant digital presence, is constantly changing.

Legal Regulation and Urgent Tasks of Control and Supervisory Activities in the Field of International Taxation of Activities of Controlled Foreign Companies and Deoffshorization

Евгений Семенов — Wed, 07 Sep 2022 15:02:02 +0200

The work resulted in recommendations on attracting young people to the civil service in order to reproduce the personnel potential of public administration, as well as to increase the attractiveness of the civil service in the labor market. For this, an analysis of the career preferences of young people, an analysis of the problems of staffing the civil service has been carried out.

Reproduction of Human Resources and Attracting Youth to the Public Civil Service

Евгений Семенов — Wed, 07 Sep 2022 14:57:02 +0200

Orientation of Vocational Education Systems to Labor Markets: Regional Differentiation

Евгений Семенов — Wed, 07 Sep 2022 14:52:03 +0200

The level of orientation of regional secondary vocational education systems to the needs of the territories in which they are located significantly affects the economic parameters of the development of the constituent entities of the Russian Federation, the dynamic characteristics of personnel demand and supply in the regional labor market.

Additional Professional Education in the Russian Federation by 2021: Needs and Efficiency

Евгений Семенов — Wed, 07 Sep 2022 14:46:02 +0200

The paper presents some generalizing results of a comprehensive analysis of the state, structure, and features of the system of additional professional education that has developed by 2021.

Analysis and Assessment of the Socio-Economic State of Regional Systems of Preschool Education

Евгений Семенов — Wed, 07 Sep 2022 14:42:02 +0200

The scientific report presents the results of the analysis of the resource provision of the preschool education system at the expense of budgetary allocations of the consolidated budgets of the constituent entities of the Russian Federation, an assessment of the socio-economic state of preschool education in the Russian regions is given.

Functioning of Regional Secondary Vocational Education Systems in Conditions of Socio-Economic Uncertainty

Евгений Семенов — Wed, 07 Sep 2022 14:34:02 +0200

The scientific report presents the results of a study of the impact of the coronavirus pandemic and, as a consequence of the growth of socio-economic instability on the functioning of regional systems of secondary vocational education, during the period of the forced transition of professional educational organizations to distance learning

Analysis of Mechanisms for Managing the Quality of Education in the Russian Federation Based on ‘Big Data’

Евгений Семенов — Wed, 07 Sep 2022 14:30:02 +0200

The purpose of the research: development of mechanisms for optimizing the quality management system of education at various levels in the digital environment based on methods of working with big data.

Indicators of the Development of Urban Educational Institutions As Factors of the Economic and Spatial Development of the City and Urban Agglomeration, Based on the Results of International Studies Devoted to This Issue

Евгений Семенов — Wed, 07 Sep 2022 14:26:03 +0200

In the current economic situation, both in the Russian Federation and in the developed countries of the world, the education system is increasingly becoming a factor in successful economic and spatial development.

Development of a System of Personal Support of Teachers Within the Framework of the National System of Professional Growth of Pedagogical Workers

Евгений Семенов — Wed, 07 Sep 2022 14:22:02 +0200

A teacher of the XXI century must be a competent, dynamic, responsible and creative specialist, therefore the National Education project within the framework of the federal project Teacher of the Future (4.5) sets the task of introducing a national system of professional growth of teachers and implementing individual trajectories for the development of professional skills of teachers in accordance with their needs and conditions for the modernization of the general education system

Methods for Assessing the Quality of Public Information Resources of Educational Organizations

Евгений Семенов — Wed, 07 Sep 2022 14:17:03 +0200

In the process of solving the legislatively set tasks of information openness of educational organizations ((hereinafter - PA), significant results have been achieved in the creation of official websites, which provide normatively required information about the activities of educational organizations. The achievement of such results is facilitated by the active position of regional and municipal education authorities and supervisory authorities. exercising control over compliance with the requirements for the structure and content of a special section of the official sites Information about the educational organization

Data-gravity and Data Science: Educational Approaches and Solutions

Евгений Семенов — Wed, 07 Sep 2022 13:27:02 +0200

In the context of fundamental changes in the economy and the labor market, the introduction of educational programs in the field of data analysis and machine learning at all levels of education with the priority of integrating mathematical, natural science and socio-humanitarian knowledge becomes important. An overview and analysis of foreign experience and main discussion topics in the development of educational modules for data science and machine learning for adolescents and adolescents is presented.

Research of Mechanisms Ensuring the Realization of the Rights of Children From 1.5 to 3 Years Old To Receive Preschool Education

Евгений Семенов — Wed, 07 Sep 2022 13:11:03 +0200

The scientific report examines the history of the emergence and formation of the system of public education of young children in Russia and abroad. The analysis focuses on the education of children from 1.5 to 3 years old. The necessity of a much larger-scale approach to the issues of additional professional education of teachers (retraining, advanced training), taking into account the specifics of the education of young children, is substantiated.

Structure and Parameters of Secondary Vocational Education Development Scenarios in the Russian Federation Until 2035

Евгений Семенов — Wed, 07 Sep 2022 11:54:03 +0200

The purpose of the preprint is to present a scientific approach to the development of scenarios for the development of the regional system of secondary vocational education.

Influence of External Factors on the Functioning of the Education System

Евгений Семенов — Wed, 07 Sep 2022 11:49:04 +0200

The work on the materials of Russian and foreign studies analyzes the degree and direction of the influence of various external factors. Economic, technological, social, geographic, cultural, linguistic and political factors can be named among the most strongly influencing external factors on the education system at the national and regional level.

Socio-economic effects of education: analysis of data from OECD countries and Russia

Евгений Семенов — Wed, 07 Sep 2022 11:40:02 +0200

The report analyzes the relationship between educational and socio-economic indicators using international statistics. Based on the analysis of international databases and a review of literary sources, hypotheses about the relationship between the indicators of educational systems and the effects of education for society, the economy and the individual are formed, methods of analysis are selected, indicators for analysis were chosen.

Employment of Youth With Higher Education and Pandemic Lessons Scientific Report

Евгений Семенов — Wed, 07 Sep 2022 11:30:02 +0200

The scientific report presents the results of a monitoring study on the employment of youth with higher education, conducted in 2020 and capturing the first wave of the coronavirus pandemic

The Construction Of A 'Human Human Being' In The German Mysteries - A Software Image Of A Urban Bourgeois

Евгений Семенов — Wed, 07 Sep 2022 11:26:03 +0200

German-Austrian cultural studies at the turn of the 20th and 21st centuries are characterized by a "new interest" in medieval preaching. If earlier it was studied by theology, literary criticism, linguistics and history as a document fixing the status quo, the existing state of affairs in a particular area - ethical norms, genre features, functioning features (pragmatics), grammatical forms and evidence of events - now preaching explored in its orientation to the future, as a genre within which promising models of behavior are developed.

Temporal Turn in the Theory of Historical Knowledge at the Border of the XX-XXI Centuries

Евгений Семенов — Tue, 06 Sep 2022 14:32:02 +0200

Despite the fact that historians almost always recognized that time is important for historiography or simply identified time with history (like Jules Michelet, who said that history is time, or Marc Bloch, who called history the science of people in time), only recently the necessary prerequisites were formed for historical time (its nature, structure, models of periodization and ways of experiencing) to become the direct subject of modern theory of history. This new state of affairs in the field of theory is today more and more often referred to as the temporal turn.

The Permutation Test Speaks in Favor of the Hypothesis of the Altai Linguistic Macrofamily

Евгений Семенов — Tue, 06 Sep 2022 14:13:02 +0200

This preprint uses the method of statistical processing of lexical lists developed by the authors: transcription of consonant classes and a weighted permutation test. The experiment involves five language families, presumably forming the Altai macrofamily: Turkic, Mongolian, Tunguska, Korean, Japanese. A strong signal was revealed between the so-nuclear Altai taxa: Türkic, Mongolian, Tunguska, which can be explained as a genealogical relationship, partially obscured by contacts. A signal of kinship was revealed in the Japanese-Turkic and Japanese-Tungusic couples (the contact scenario is poorly suited for these couples).

Social Design as a Kind of Religious Imagination (on the Materials From the History of Russian Thought of the Late XIX – Beginning of XX Centuries

Евгений Семенов — Tue, 06 Sep 2022 14:01:03 +0200

The subject of the research is religious social projection in pre-revolutionary Russia.

Postmigration Societies: Economics, Politics, Culture

Евгений Семенов — Tue, 06 Sep 2022 13:55:02 +0200

To understand the depth of transformations in all spheres of society generated by migration, new terminology is needed. The notion of “postmigrant societies” implies that the distinction between local and migrant population loses its relevance in certain social spheres. According to the familiar epistemological framework, societies are presented as consisting of “local population” on the one hand, and “migrant population” on the other

Political Accommodation of Cultural Differences in Industrialized Societies

Евгений Семенов — Tue, 06 Sep 2022 13:47:03 +0200

The notion of “political accommodation” applied to the theory and practice of managing cultural diversity could enrich the Russian academic dictionary. Liberal democratic states invented specific mechanisms for political accommodation of cultural differences. Thanks to these mechanisms, the part of the population of a democratic state that is not ready to dissolve into the ethnocultural majority is more or less protected.

The Relationship Between Government and Business in the Context of the Formation of Innovation Clusters and Ecosystems in Russia

Евгений Семенов — Tue, 06 Sep 2022 13:40:02 +0200

Based on the formation of innovative clusters and ecosystems in Russia, the network organization and system principles for transforming the relationship between the state and innovative business are considered. The focus focuses on the formation of innovation clusters and ecosystems as collaborative communities, the transition to a “cluster management organization” as a new advanced form of organization of the innovation process, as well as government policy to support such a transition along with government and business relations in this context.

Inequality of Social Burden: Features of the Socio-Economic Situation of the Population Experiencing the ‘Sandwich Syndrome’

Евгений Семенов — Tue, 06 Sep 2022 13:14:02 +0200

In this paper, a study of the socio-economic situation of persons experiencing "sandwich syndrome" is carried out. The work includes a critical analysis of the literature on the impact of the "sandwich syndrome" on various aspects of human life, as well as an empirical analysis of the prevalence, demographic and socio-economic characteristics of the "sandwich syndrome" in Russia.

The Concept of a New Social House

Евгений Семенов — Tue, 06 Sep 2022 13:09:02 +0200

The preprint is written on the basis of the research work results obtained by the team of the Institute for Social Analysis and Forecasting, RANEPA in 2020, and includes both a systematic review of foreign literature on aging and an analysis of interviews with native and foreign experts in the field of active aging. The concept of separation of older citizens, their separate living in specialized houses or settlements prevailed for a long time until it was modified several decades ago into another concept confirmed by numerous studies and known as "aging at home". However, the strict limitation of living space within a house leads to social exclusion, the risks of which are especially high among the elders. In this regard, it seemed meaningful to develop the concept of a new "social house", which can be applied both in designing new residential complexes and in renovation or adaptation the existing residential complexes and social infrastructure to the needs of the older generation. The results of the work can be used for scientific and methodological support of programs and strategies in the field of aging and old age, for state policy formation in the field of social protection of the elderly people, as well as for the development of specific directions, measures, and mechanisms of state policy.

Characteristics of Migration Flows and Settlement of Migrants in the South of Russia

Евгений Семенов — Tue, 06 Sep 2022 11:56:02 +0200

This preprint examines the migration of the population of the regions of the South of Russia in the second half of the 20th - early 21st centuries. Migration processes are considered in two “dimensions”. On the one hand, their development is investigated in a historical perspective, in connection with which migration in the Soviet and post-Soviet times is considered separately. On the other hand, migration flows are opposed to each other in terms of "distance", for which intraregional and interregional migrations are separately characterized.

Regional Measures to Support the Birth Rate in the Russian Federation in the 2010s: Dynamics of the Main Characteristics

Евгений Семенов — Tue, 06 Sep 2022 11:53:03 +0200

The preprint systematizes information on measures to support the birth rate in the Russian Federation, acting at the regional level. The main attention is paid to measures provided at the birth of a third child, which include regional maternity capital, monthly allowances for families with three or more children, and the provision of land plots to large families. Changes in the regional system of measures to support families with three or more children from 2011 to 2019 are considered.

Dynamics of Non-Criminal 'Shadow' Employment of the Employee Population

Евгений Семенов — Tue, 06 Sep 2022 11:49:02 +0200

The results of the study represent the Russian experience in the sociological study of the non-criminal “shadow” labor market, including the identification of trends in its development, analysis of socio-economic mechanisms, in particular the socio-psychological attitudes of participants in “shadow” processes, norms of legal and economic consciousness, value orientations, and motives of behavior. that determine the massive participation in the non-criminal "shadow" economy of representatives of different social, demographic and professional groups.

Building a Quality System in Medical Organizations: International and Russian Experience

Евгений Семенов — Tue, 06 Sep 2022 11:35:02 +0200

The scientific report presents the results of a study of various approaches to the construction of modern quality management systems in medical organizations. Trends in the development of healthcare systems in the world and in the Russian Federation are analyzed, it is shown what role, on the one hand, the development of the infrastructure of medical care for the population, the staff of medical organizations, and on the other hand, the satisfaction of patients with the quality of the services provided to them by the medical organization, plays.

Analysis of Behavior in the Labor Market of Elderly Aged Persons: All-Russian Trends and Typology of Regional Models

Евгений Семенов — Tue, 06 Sep 2022 11:27:03 +0200

The object of the study is the behavior of older people in the labor market in Russia.

Methods for Managing the Health and Active Longevity of the Population Over the Working Age in Russia: Prospects for Improvement

Евгений Семенов — Tue, 06 Sep 2022 11:21:03 +0200

At present, great importance is attached to the problem of maintaining the professional health of the working-age population and prolonging professional longevity in the world and in the Russian Federation. This problem has become especially urgent in recent years, in connection with the change in the country's retirement age

Analysis of Modern Organizational and Information Technologies in the Management of Professional Health and Professional Longevity

Евгений Семенов — Tue, 06 Sep 2022 11:16:02 +0200

Analysis of Gender Differences in Life Expectations and the Role of Individual Value Orientations

Евгений Семенов — Tue, 06 Sep 2022 11:01:03 +0200

This paper presents the results of a study of the links between the gender gap in life expectancy, on the one hand, and differences in value attitudes towards a healthy lifestyle between men and women, on the other

Multi-Regional Demographic Forecast for Russia: Consequences of the COVID-19 Pandemic

Евгений Семенов — Tue, 06 Sep 2022 10:36:03 +0200

Analysis of Chronic Poverty Factors

Евгений Семенов — Tue, 06 Sep 2022 10:24:02 +0200

The purpose of this study is to assess the prevalence and identify factors of chronic poverty

Social Situation in Russia in 2020: Macroeconomic Indicators, Labor Market and Population Income

Евгений Семенов — Tue, 06 Sep 2022 10:13:02 +0200

The work resulted in an analysis of the social situation in the Russian Federation in 2020. The object of the study was the population of the Russian Federation. In the course of the work, an assessment of the socio-economic situation of the population was carried out on the basis of a wide statistical spectrum of indicators affecting income and material situation of the population, the labor market, retail trade, consumer prices, etc. The basis for achieving the result was provided by continuous monitoring, covering operational statistical observation data. The estimates obtained are based on the results of monitoring carried out by the Institute for Social Analysis and Forecasting of the RANEPA since 2015

Growth Factor in the Level of Pension Provision in the Medium and Long Term

Евгений Семенов — Thu, 01 Sep 2022 16:43:02 +0200

The decisions made in 2018 related to raising the retirement age in Russia, in conjunction with previously adopted measures, created opportunities for pensions to rise above inflation and stabilize the ratio of pensions to wages until 2028.

Numerical investigation of load characteristics by internal solitary wave on submarines in fluids with continuous density change

Anqing LAI — Tue, 23 Aug 2022 16:39:05 +0200

Internal solitary waves (ISW) often appear in the actual ocean and carry huge energy. In order to study the interaction between the ISW and the underwater objects, considering the variation law of the fluid density along the depth direction in the actual ocean, the numerical calculation model for the ISW and the submarine in the stratified fluid is established based on the Korteweg de Vres (KdV) theory and the RANS method. The load characteristics of the ISW on the submarine are studied by using the overset mesh technology and the method. When the submarine passes through the ISW, the change of its buoyancy will cause a sharp change in the vertical load. The ISW-induced flow field will also affect the force on the submarine. The ISW-induced forces increase with the increase of the ISW amplitudes. When the submarine is completely below the peak of the waveform, the load is mainly affected by the flow field structure; the force amplitude is small, and the impact of the submergence depth is small.

Explicit time integration scheme with large time steps for first order transient problems using finite increment calculus (preprint)

Eugenio Oñate — Tue, 23 Aug 2022 11:01:13 +0200

We present an explicit integration scheme for solving the transient heat conduction equation that allows larger time steps than the standard forward Euler scheme. The derivation starts from a higher order form of the governing differential equations of the problem obtained using a Finite Increment Calculus (FIC) procedure. The efficiency of the new explicit integration scheme in terms of substantial gains in the time step size versus the forward Euler scheme is verified in the solution of transient heat conduction problems in one and two dimensions. The method is readily extendible to other problems in mechanics governed by the first order transient differential equation.

Exploration of the Influence of High Rate Cooling Crystallization Parameters on the Preparation of Ammonium Perchlorate Crystals Using Taguchi's Method

zahra khodadadi — Thu, 18 Aug 2022 07:50:02 +0200

'''Preparation of fine ammonium perchlorate (AP) particles and thermal behaviour of it are known as the most important challenges in the crystallization and propellant sciences. We introduced an effective method of fine AP preparation named high rate cooling crystallization (HRC). This work presents application of Taguchi approach for optimizing the HRC method. In this study a set of experiments was designed according to the Taguchi L9 array. Experimental design was originated from four effective parameters containing; temperature, pressure, solvent type (water and ethanol) and anticaking agentsodium dodecyl sulfate (SDS). After preparation of fine AP particles average particle size (APS) was measured using laser mass spectrometry (LMS-30). APS, contribution, and the analysis of variance (ANOVA) were used to investigate performance factors affecting the operation condition. According to the data obtained, anti-caking agent and solvent type were represented the main effect on the preparation of micronized AP by using HRC method. Furthermore, the optimum condition in preparation of fine AP particles by using HRC method was ethanol solvent, 10atm pressure, 0.4 % SDS, and 60˚C temperature. Thermal behaviour of the optimized particles was investigated using TG/DSC analysis. Finety of the particles positively shifted the low temperature decomposition (LTD) region of fine optimized sample in comparison with coarse pure AP. Crystallinity of sample was confirmed by SEM and XRD analysis.

Synthesis of Nano Porous Silica-titania Membrane with Photocatalytic Properties

zahra khodadadi — Wed, 17 Aug 2022 11:50:02 +0200

In this study, the photocatalytic properties of nanoporous silica-titania membrane was investigated. For this purpose, nano-porous silica-titania membrane was prepared by sol-gel process using tetraethyl orthotitanate and tetraethyl orthosilicate with the intermediate layer of colloidal titania on α-alumina support. The as-prepared membrane was characterized by FTIR, XRD, FESEM and BET techniques. The specific surface area of microporouse silica -30% titania powder was 507 m2/gr. In addition, the photocatalytic activity of the as-prepared membrane was studied for methyl orange photo-degradation under UV light (λ

Numerical study of turbine rim seals performance with different sealing structures

Tao Bai — Fri, 22 Jul 2022 11:04:15 +0200

The unsteady large-scale vortex near the turbine rim has an important influence on the sealing performance. Characteristics and performance of four sealing structures are researched in this paper. Three-dimensional unsteady numerical simulation was adopted to deeply reveal the characteristics of the rim sealing vortex and its influence mechanism on the rim sealing performance. The results show that the rim seal vortex structure induced by the interaction between ingested gas and sealing flow in the gap is the leading cause of unsteady flow in the rim. The vortex size is suppressed with the increasing seal flow rate or a Chute seal structure. However, the rim seal vortex exit in the cavity gap under a low seal flow rate can suppress the gas intrusion and improve the sealing efficiency of the turbine cavity even with a simple sealing structure. The Chute sealing structure achieves better performance among the four sealing structures studied in this paper. It can achieve complete sealing under a low sealing flow rate of 0.5% and has less impact on the aerodynamic performance of the mainstream even with high sealing flow rate. The research of this paper has guiding significance for further understanding the sealing mechanism and optimizing the design of the sealing structures.

Establecimiento de un plan de manejo para la reducción de estereotipias en individuo de Eira Barbara

ANA CAMILA BELTRAN URREGO — Tue, 19 Jul 2022 18:58:03 +0200

Se buscó desarrollar un plan de manejo para el caso de estereotipias reportadas en un ejemplar hembra de Taira (Eira barbara) dentro de las instalaciones de la fundación Zoológico Santacruz que contemple la creación e implementación de multiples herramientas para cada uno de los 5 dominios del bienestar animal. Se realizó una evaluación inicial para determinar los valores base que serán comparados, para lo cual se determinó la necesidad de rebalancear la dieta del individuo y crear un programa de enriquecimiento ambiental intensivo que reduzca el hallazgo de incidencia de estereotipias del 30.55% del total del tiempo evaluado.

FIBRESHIP, el gran reto de usar materiales compuestos en la construccion de buques de gran eslora

Materiales Compuestos — Fri, 15 Jul 2022 02:34:06 +0200

FIBRESHIP (H2020, Grant 723360) es un ambicioso proyecto de innovacion naval financiado por la Comisión Europea, en el que participan 18 socios europeos que estan coordinados por la empresa española Tecnicas y Servicios de Ingenieria (TSI). El objetivo principal de FIBRESHIP es superar el gran desafio tecnologico que supone sustituir los materiales metalicos utilizados actualmente en la construcción de grandes buques por materiales compuestos.

Para llevar a cabo este reto, se está abordando el proyecto desde diferentes puntos de vista: i) análisis de negocio y potencial mercado de los buques; ii) análisis y modelado numérico de los materiales compuestos seleccionados para su construccion; iii) diseño estructural del barco usando programas de simulación numerica; y, iv) análisis de los procesos de construcción naval aplicadas a esta tecnología, de monitorización y de ciclo de vida.

El estudio e implantación de composites para la construccion de buques de gran eslora se está llevando a cabo a través del diseño de tres tipos de buques de más de 50 metros, los cuales son considerados como los más prometedores en el mercado: un portacontenedores de 245 metros de eslora entre perpendiculares, un ROPAX de 185 metros y un oceanográfico de 80 metros. Además, se están desarrollando modelos numéricos específicos los cuales están siendo validados a través de campañas de ensayos. Por ultimo, tambien se estan desarrollando diferentes estrategias de medición de salud estructural y modelos de producción adaptados a esta tecnología.

Hacia estructuras aeronáuticas de material compuesto más eficientes a través de resinas termoplásticas

Materiales Compuestos — Fri, 15 Jul 2022 02:12:04 +0200

Airbus Defence and Space está desarrollando procedimientos de fabricación fuera de autoclave factible para estructuras en fibra de carbono con resina termoplástica en términos de impacto ambiental, coste, cadencia de producción y rendimiento.

Este objetivo se centra en la deposición automática de fibras y la consolidación in situ de preimpregnados termoplásticos, incluida la co-consolidación con larguerillos previamente consolidados mediante un proceso conformado continuo. La integración de componentes y la reparabilidad de las estructuras resultantes se beneficiarán de las características de reprocesamiento y soldadura de los polímeros termoplásticos.

Para desarrollar y demostrar la potencialidad de estas tecnologías y su aplicabilidad a los aviones militares y civiles, se están realizando varios demostradores: fabricabilidad, pruebas y especímenes para ensayo; estructura primaria y secundaria y demostradores de reparabilidad. El más ambicioso de ellos es actualmente el revestimiento superior de un cajón de torsión de estructura primaria que se instalará en una plataforma C295 junto con otras tecnologías emergentes dentro de Airframe Integrated Technology Demonstrators de Clean Sky 2.

Esta conferencia mostrará una visión global de la hoja de ruta del desarrollo termoplástico dentro de Airbus Defence and Space.

Sección de cajón de ala altamente integrado, fabricado por laminado automático de fibra seca e infusion de resina, desarrollado por Airbus Defence and Space

Materiales Compuestos — Fri, 15 Jul 2022 01:56:05 +0200

Airbus Defence and Space está desarrollando una sección del cajón de torsión del ala en fibra de carbono e infusión de resina epoxi para el protipo FTB#2 del Programa de I+D europeo Clean Sky 2. Se integran, en una sola parte de infusión, el revestimiento inferior con larguerillos, y los largueros anterior y posterior. Se emplea laminado automático de fibra seca y conformado en caliente los largueros, larguerillos y rigidizadores previo a la infusión.

Este artículo muestra el concepto de diseño, pasos y logros alcanzados, de cara al objetivo final de conseguir el TRL6 en el prototipo del Clean Sky 2.

Las pruebas de fabricabilidad han crecido gradualmente en completjidad hasta llegar a producir subcomponentes representativos de una sección altamente integrada para un cajón de ala.

Se ha caracterizado el material seleccionado, y se esstá completando la piramide de ensayos estructurales; desde los cupones (ensayos ya terminados), pasando por los subcomponentes (también finalizados) a falta del ensayo “full scale” a carga última de una sección completa del ala exterior.

Recipiente a Presión Toroidal para Almacenamiento de Hidrogeno

Materiales Compuestos — Fri, 15 Jul 2022 01:45:19 +0200

El futuro del transporte, pasa por dos variantes, almacenamiento energético en baterías o almacenamiento de hidrogeno para consumo como combustible. En el caso de la utilización de hidrogeno, es necesario almacenar el mismo en recipientes adecuados que den al vehiculo una autonomía suficiente similar a la que tendría con otro tipo de combustible como la gasolina o el gasoil. Los recipientes de materiales compuestos, son una solución idónea para la solución de este problema, dada su relación resistencia peso muy favorable frente a los metálicos. Una de las soluciones que actualmente se están estudiando es utilizar recipientes a presión de forma toroidal la cual se adapta muy bien a las disposiciones típicas de los vehículos actuales. Por otra parte se puede ver en este trabajo que esta forma de recipiente tiene ventajas evidentes. Se ha utilizado un material como el AS4D/9301 (Carbono-epoxy), obteniéndose una solución que cumple con el criterio de fallo de Tsai-Wu para obtener un diseño correcto, mediante una simulación por el Método de Elementos Finitos.

Development and characterization of a composite leaf spring, with bucking working

Materiales Compuestos — Fri, 15 Jul 2022 01:24:04 +0200

For a long time, metal leaf springs have been used as elastic element, merging them with helicoidal spring for suspension applications.

This type of system based on ferrous materials combined in independents plies, presents multiple problems such as interface friction, or its poor behavior in plastic state. These conditions lead to a mechanical property lost through a period of time, evoking fatige problems. Throughout this project a high strength unidirectional leaf spring based on glass fiber composite material has been developed with the purpose of solving these problems.

To ensure an adequate service life, an bicomponet based material has been selected, improving its process. CRTM has been chosen for the processing of the prototypes. Finally, taking other related problems away is possible thanks to multiple CAD implementations tools.

So with this as the backdrop, a one blade leaf spring under a buckling situation has been designed, solving all the existing problems found in current iron technology. Under the scope of industrial implementation and optimization, composite advantages related with flexibility and lightweight can be resourceful.

Study of the influence of concrete on the thermal properties of vinilester-uretane composites vs accelerated tests

Materiales Compuestos — Fri, 15 Jul 2022 00:38:02 +0200

Specifically, the use of vinyl ester resins has been studied profusely in both the maritime and industrial sectors and with less time, in the use of reinforcement in civil engineering structures and architecture as passive reinforcements. The resin used in the present work is novel, and still little used. It is vinyl ester resin of bisphenol-A segment modified with urethane. This presents a greater resistance to chemical agents such as those of the petroleum industry, alkaline agents and vapors; together with a lower exotherm that facilitates the manufacture of thick laminates.

A thermal and mechanical characterization has been carried out through the techniques of Differential Scanning Calorimetry (DSC), Infrared Spectroscopy (FTIR) and Thermogravimetry (TGA) of said resin reinforced with high grammage (780 g / cm2) fiber of E glass to evaluate the degradation of the composite and its mechanical properties to the interlaminar shear and bending. The influence of the contact with self-compacting concrete (HAC) on said material, imbedded inside its matrix as a reinforcement, as if it were a passive reinforcement, as well as an accelerated aging study in solution simulating the exudation liquid of the concrete pores (LPH) through said characterization. With the obtained results, it is evaluated and compared, from the point of view of degradation-stiffening vs. mechanical properties, with the traditional Bisphenol-A (VEBA) resins, as well as its suitability for the aforementioned applications, resulting in a resin with better properties than the VEBA.

Delamination behavior under mode I and mode II of adhesive bonded joints for different surface treatments

Materiales Compuestos — Fri, 15 Jul 2022 00:18:05 +0200

The automotive, aerospace and renewable energy generation industries have replaced significantly the use of traditional materials, such as steel and aluminum, by reinforced fiber composites. It has recognized that joints drilling and screwing joints damage the fibers introducing a higher concentration of stresses. That is why the application of structural adhesives, as a method of joining in reinforced composites, has increased in recent years. Delamination is the most critical failure mode of composite materials resulting in stiffness and structural strength losses.

This works studies the behavior against delamination under mode I and mode II interlaminar fracture of adhesive bonded joints in carbon-epoxy composite materials, using structural adhesives of epoxy and acrylic bases. For the execution of the joints, different surface treatments have been employed: sanding, grit blasting and peel ply technique, allowing to make a fracture resistance comparision study. The double cantilever beam (DCB) and end notched flexure (ENF) tests configuration were used to determine stress-strain behavior and fracture toughness for mode I (GIC) and mode II (GIIC), respectively. Surface modifications have been evaluated by contact angle measurements and scanning electron microscopy (SEM). The experimental results are shown in the same situation. The experimental results obtained show that, even if not showing the same delamination tendency for both fracture modes, the strain energy release rate are higher for an improved of wetting properties and an increase of surface roughness.

FE Mechanical properties prediction of CFRP considering different carbon fiber surface treatments

Materiales Compuestos — Thu, 14 Jul 2022 18:19:03 +0200

Reinforcement/matrix interaction is recognized as a key issue in polymeric composite materials. From the mechanical point of view, being the link between the fibres and the polymer, a proper load transfer is ensured only if a good enough interphase exists. This is particularly critical in carbon fibre (CF) composites since, due to the non-polar characteristics and chemical inertness of carbon, sometimes they exhibit weak interfacial adhesion. In this sense, various surface treatments for CFs are currently being investigated, in order to improve their interaction with the polymeric matrices: wet chemical or electrochemical methods, chemically or physically activated oxidation procedures, application of thin coatings and plasma treatments. This is precisely one of the challenges addressed in the MODCOMP project.

This paper describes part of the work carried out within the mentioned project in order to estimate the improvement of properties that can be achieved through enhancements of the CF/epoxy interphases. The study covers both elastic engineering constants and strengths predictions, and it has been performed using finite element models of RVEs of UD fibres and introducing cohesive elements to take into account the interfacial failure mode. The results obtained allow identifying which range of CF/epoxy interphase properties enhancement should be achieved in order to get significant effects in the composites mechanical response.

Simulation of a pultrusion process of composite material profiles reinforced with carbon fiber for aeronautical applications

Materiales Compuestos — Thu, 14 Jul 2022 18:08:03 +0200

The manufacture by means of a pultrusion process allows to obtain structural profiles of composite materials, avoiding discontinuous processes that need the use of an autoclave to cure the material. This process usually uses fiberglass as reinforcement, not reaching the necessary qualities in structural aeronautical applications. The present work develops a numerical simulation of the pultrusion with composite materials reinforced with carbon fiber for aeronautical structural applications. In order to obtain high quality materials, a product development is required where the process parameters are studied. In this sense, a complete study of the pultrusion process has been carried out through the development of numerical simulations using the software ABAQUS and NASTRAN / PATRAN from the point of view of the material manufactured and the pultrusion mold used.

These two approaches have been developed by generating finite element models. In the first place, models that simulate and predict the physical-chemical properties of the material, such as the glass transition temperature and the degree of final curing of the material before processes with different temperature settings, draft speeds and geometries. Second, the pultrusion mold was simulated to obtain the expansions and loads applied to the fabricated profile to evaluate the influence of this on the pultrusion process and the quality of the obtained profile.

The results obtained have been correlated by mechanical and physical-chemical tests as well as manufacturing tests that obtained the simulated profiles in order to introduce the technology and the parts manufactured in future aeronautical structures.

Load rate influency over delamination failure in composites

Materiales Compuestos — Wed, 13 Jul 2022 14:25:04 +0200

Impact is one of most critical stress over a structure, so as it induces a high strain rate on the material. Under low speed transverse impacts in composites, the secuence of material degradation is: intralaminar fracture of the matrix that does not mean a load bearing capacity decrease but makes it easier the starting of the seconf failure mode: the interlaminar failure of the matrix or delamination and, finally, the intralaminar failure of fibre.

Delamination is one of the most critical failure mechanisms in composites because it means an important bearing capacity loss, It is quite difficult to detect visually and it's evolution determines the subsequent failure of the component. That behaviour depends on it's interlaminar fracture toughness. Nowadays there is not a general agreement over the dependency between interlaminar fracture toughness, in Modes I&II, and the strain rate. Nevertheless several biaxial equi energy impacts show that delaminated area increases as same as load rate application, so it is clear a dependency between fracture energy and load rate.

This work shows the set-up and first results of a Mode I test using a drop weigth impact tester.

Compression after impact test on woven CFRP laminates: the effect of ply clustering

Materiales Compuestos — Wed, 13 Jul 2022 14:13:06 +0200

One of the mayor threats for FRP is the out-of-plane loading conditions such as impacts, which produce interlaminar failures, among others, decreasing drastically the material's strengths in plane. Drop weight and compression after impacts tests have been selected as the standard methodology to evaluate laminate performance under impact loadings. The present work aims to reveal the influence of the material structure in woven laminate response under impact. To this end a complete set of experiments was designed using the actual ASTM standards (D7136/D7137), including the actual monitoring capabilities to address this problem. Composite coupons, made of AGP 280-5H carbon/Epoxy satin, were manufactured using three laminate configurations to analyze the effect of ply clustering [(+-45)/(0/90)]4S, [(+-45)2/(0/90)2]2S, and [(+-45)4/(0/90)4]S).

Laminates have been subjected to low velocity impact using an INSTRON-CEAST Fractovis 6875 drop weight tower while compression test has been performed using a INSTRON 250 kN. Impact tests have been recorded with two high speed video-cameras (Photron SA-Z 2100K) configured at 20000 fps in order to analyze the plate behavior during the impact. In addition, a three dimensional high velocity digital image correlation (3D-HV-DIC) analysis has been done with the VIC-3D 7 system to measure the out of plane displacement and strains evolution. Also 3D-DIC analysis has been carried out for the CAI test to check the validity of the failure modes. It has been observed that the most clustered laminates increase the perforation threshold, while it decrease the residual strength of the material, due to damage spreading effect.

Biaxial testing on CFRP laminates cruciform specimens under compressive loads

Materiales Compuestos — Tue, 12 Jul 2022 22:39:04 +0200

A numerical and experimental study is performed on biaxial tests with cruciform specimens in which at least one direction is under compression. Continuous carbon fibre reinforced polymer matrix laminates are studied in angle-ply sequences. The high complexity of the biaxial test is analysed, highlighting the non-linear behavior of the material with pseudo-ductile response. In addition, the presence of compression loads lead to tests in which it is necessary to avoid instabilities in order to obtain adequate results. The numerical simulations based on the Finite Element Method allow to study of the initiation and evolution of the damage in the laminate. The combination of numerical techniques with experimental results, obtained by means of the test instrumentation with strain gauges and Digital Image Correlation, allows to perform a complete characterization of the behaviour of the material in order to achieve less conservative designs of composite structures.