Balanced Growth Rate Research Articles

Microstructure and mechanical properties of TiB2-TiNw ceramic composite fabricated by SPS

A TiN whisker toughening TiB2 based ceramic composite was fabricated by spark plasma sintering (SPS). The influence of sintering temperature and holding time on the microstructure and mechanical properties of the composite was investigated. The results indicate that, at a sintering temperature of 1500 °C and a holding time of 9 min, the composite exhibits a relative density of 99.24 %, flexural strength of 906 MPa, fracture toughness of 8.6 MPa m1/2, and Vickers hardness of 22.3 GPa. The sintering aid composed of Ni and Mo within the composite significantly enhanced atomic diffusivity in TiB2 grains, promoting a balanced grain growth rate. SPS technology promoted the rapid formation of numerous necks between TiB2 grains in a very short duration. Concurrently, the pinning effect exerted by TiN whiskers effectively inhibited excessively rapid migration of grain boundaries. These factors ensured that the composite could achieve optimized microstructures and good mechanical properties at a low sintering temperature.

Dynamic models for developing reference scenarios of energy system in the low-carbon transition

The proposed study is aimed at the development of dynamic input-output models in relation to energy development systems. The main task is to find optimal scenarios, defined as sequences of optimal balances between production and capital investment. These models are rooted in Leontief's conceptual concept of input-output, which emphasizes the timing of the introduction of new production systems. The article discusses the economic interpretation and mathematical conditions of intersectoral models, and examines their application to problems related to energy. The model uses the concept of balanced equilibrium growth, in which the ratio of consumption to net release is the same for all resources, and the reserve of at least one resource is fully utilized. The growth rate of the system is the most important parameter that determines the trajectory of balanced growth. Solving the system of inequalities yields balanced growth trajectories in which the dominant root and the associated vector of characteristics plays a key role. A balanced equilibrium growth rate has the properties of a minimax with the presence of a saddle point, which indicates its importance in achieving market equilibrium while preventing a reduction in inventories. The practical application of the model is described. The results of calculations of pessimistic, reference and optimistic scenarios of electricity production in the IPS of Ukraine are presented. Official statistical information and economic forecasts are used, and various restrictions are taken into account. The model aims to minimize the total cost of electricity generation while respecting environmental and operational constraints. The proposed model provides a comprehensive basis for understanding the dynamics of resource reserves, consumption and growth of electricity production of the IPS of Ukraine. It offers decision-makers a valuable tool to optimize electricity generation strategies, taking into account a range of scenarios and constraints, for the sustainable and cost-effective operation of the energy system. Keywords: Dynamic input-output models, optimal scenarios, balanced equilibrium growth, growth rate of the system.

Role of efficiency and composition of public infrastructure: implications for growth and employment

ABSTRACT This paper contributes to theoretical endogenous growth literature, establishing the role of efficiency of public infrastructure use by private/public production sectors and composition of public infrastructure (i.e. proportion of public infrastructure directed towards productivity-enhancing purposes) in growth-process. For a small open economy with private/public production sectors, at free trade, increases in efficiency of public infrastructure use by private/public production-sector increase balanced growth rate, ratios of economy-wide aggregate-level of (i) private to public capital and (ii) employment to public – capital, under restrictions on efficiency – composition mix of public infrastructure and the free trade price, given other model-parameters; i.e. effect of efficiency-increase depends on public infrastructure composition. Thus, assessment of macroeconomic implications of employment should consider efficiency and composition of public infrastructure.

Developing artificial mixed diets for larval culture of sea cucumber, Holthuria leucospilota, and their effects on the internal microbiota

During the seedlings culture of sea cucumbers including Holthuria leucospilota, natural microalgae are generally used as ideal food for the pelagic larvae of sea cucumbers, which lead to a strong demand for microalgae production. However, microalgae production is time-consuming and laborious and susceptible to pests and variable whether, and unstable supply of microalgae often results in culture failure of sea cucumber larvae. In this study, we tested the effect of three different diets on the growth, survival rate, and internal microbiota composition of sea cucumbers aiming to develop an artificial diet for H. leucospilota larvae. The results showed that the sea cucumber larvae fed with the mixed artificial diet (composed of Sargassum powder, chilled macroalgae solution, wall-breaking Chlorella powder, and yeast powder) had the most balanced growth rate, highest survival rate, and a higher α-diversity and abundance of Plesiocystis, Haloferula, and Firmicutes in body when they were compared to the larvae fed with the natural bait, Chaetoceros muelleri. However, the abundance of potential pathogenic bacteria, Francisella and Acinetobacter, was higher in the larvae fed with the natural bait. In conclusion, the mixed artificial diet was developed for H. leucospilota larval culture, which can be used as a good alternative to live microalga with cumbersome processes.

Mathematical properties of optimal fluxes in cellular reaction networks at balanced growth.

The physiology of biological cells evolved under physical and chemical constraints, such as mass conservation across the network of biochemical reactions, nonlinear reaction kinetics, and limits on cell density. For unicellular organisms, the fitness that governs this evolution is mainly determined by the balanced cellular growth rate. We previously introduced growth balance analysis (GBA) as a general framework to model and analyze such nonlinear systems, revealing important analytical properties of optimal balanced growth states. It has been shown that at optimality, only a minimal subset of reactions can have nonzero flux. However, no general principles have been established to determine if a specific reaction is active at optimality. Here, we extend the GBA framework to study the optimality of each biochemical reaction, and we identify the mathematical conditions determining whether a reaction is active or not at optimal growth in a given environment. We reformulate the mathematical problem in terms of a minimal number of dimensionless variables and use the Karush-Kuhn-Tucker (KKT) conditions to identify fundamental principles of optimal resource allocation in GBA models of any size and complexity. Our approach helps to identify from first principles the economic values of biochemical reactions, expressed as marginal changes in cellular growth rate; these economic values can be related to the costs and benefits of proteome allocation into the reactions' catalysts. Our formulation also generalizes the concepts of Metabolic Control Analysis to models of growing cells. We show how the extended GBA framework unifies and extends previous approaches of cellular modeling and analysis, putting forward a program to analyze cellular growth through the stationarity conditions of a Lagrangian function. GBA thereby provides a general theoretical toolbox for the study of fundamental mathematical properties of balanced cellular growth.

The Eurozone’s influence on the cyclical macroeconomic performance: comparative analysis of Slovenia and Croatia

This paper analyses the impact of cyclical external shocks on the macroeconomic performance of Eurozone and EU member countries. The latter is achieved through a comparative study of two EU countries, Slovenia and Croatia, of which only the former is a Eurozone member state. Cross-country differences are observed over the 2000-2018 period, thus covering all stages of the economic cycle. The primary hypothesis is that the Eurozone economic integration provides its members with comparably greater macroeconomic stability and balanced growth rates. The research elaborates on the possibilities and effects of more autonomous macroeconomic adjustments tailored to the specific needs of non-Eurozone EU countries. Methodologically, the study exhibits an intricate nexus among theoretical, empirical, and institutional economics and shows that the impact of the country’s international interconnectedness, stemming from the economic and geographical links, bears greater importance than Eurozone membership. Concurrently, this analysis confirms that whether the Eurozone’s benefits outweigh the shortcoming of monetary sovereignty abnegation depends predominantly on the capabilities of individual countries and Eurozone’s institutions to design and execute an effective monetary-fiscal policy mix.

Effects of monetary transactions costs on economic growth

This study explores the effects of monetary transaction costs on economic growth in a closed overlapping generations economy with cash-in-advance constraints. Working generations can also hold interest-bearing capital claims. Economic growth is powered by an engine of learning-by-doing and knowledge spillover among workers. The results indicate that reductions in transaction costs raise the balanced growth rate and possibly reduce long-term inflation and nominal interest rates.

Carbon footprint prediction considering the evolution of alternative fuels and cargo: A case study of Yangtze river ships

For reducing carbon emissions in the shipping sector, application of alternative low-carbon and zero-carbon fuels is the consensus. However, requirements of economic development cannot be ignored while focusing on emission reduction. Cargo development is an important prerequisite. Considering the cargo growth as a novelty, a method to calculate the annual carbon emissions of different alternative fuel-powered ships in different cargo growth prospects and power scenarios is proposed. With respect to the time dimension, the relationship between alternative fuels, cargo, and carbon reduction is revealed. The Yangtze River bulk carrier case was studied and the life cycle carbon emission analysis of diesel, LNG hybrid, LNG, hydrogen, methanol, and ammonia were carried out. The annual carbon curves of the high, steady, and low cargo growth prospects were obtained for different scenarios of the power system structure. The results show that LNG hybrid, LNG and methanol fuels are currently the suitable choices. Their life cycle carbon emissions were reduced by 31.5–38.1% compared with those of diesel power. The carbon emissions of green hydrogen and green ammonia were reduced by 78.8% and 91.3%, respectively, compared with those of hydrogen and ammonia. The carbon reduction results of green fuels in their initial application were explored which are at 0.6–10.8%. In addition, there is a balanced annual growth rate, whose annual carbon curve will be steady under its corresponding scenario of power system structure, which could help the ship owners plan their future.

Petroleum Price Volatility on Macroeconomic Indicators in India

The selling price of petrol and diesel in the domestic market is determined by the volatility of crude oil pricein the international market and taxes and excise duty imposed on it. India is heavily dependent on foreigncountries to meet its growing petrol-diesel demand. Consequently, net trade balance reflected in the BOP isalways adverse, which in turn adversely affects all the macroeconomic indicators and thereby, the poorperformance of the entire economy. So attempts should be made and petroleum price fluctuations in Indiamust be controlled to reduce the current inflation and to maintain a balanced growth rate in the economy.

CAN THE OPTIMAL TARIFF BE ZERO FOR A GROWING LARGE COUNTRY?

AbstractCan the optimal tariff be zero for a growing large country? To pursue the possibility, we extend the Rivera‐Batiz–Romer lab‐equipment model of endogenous technological change to include asymmetric countries, import tariffs, and either homogeneous or heterogeneous firms. Each country's domestic revenue share is a sufficient statistic for its long‐run growth rate, but it is not for its long‐run welfare. A unilateral tariff reduction by either country always increases the balanced growth rate. A zero tariff is locally optimal for a country under a mild condition, which is automatically satisfied at a symmetric balanced growth path with the zero tariff.

Environmental Taxes and Economic Growth with Multiple Growth Engines

Abstract We develop an endogenous growth model in which long-run growth is driven by three engines: private abatement R&D, expanding-variety R&D, and capital accumulation. We show that an environmental tax activates private abatement by directing researchers from the variety R&D sector to the abatement R&D sector, which helps the economy avoid the environmental disaster. Our results also show that the effect of the environmental tax on long-run growth is uncertain, depending mainly on the relative productivity between the two R&D sectors. If the abatement R&D sector is sufficiently productive, increasing the environmental tax will enhance the balanced output growth rate and social welfare.

Optimal proteome allocation and the temperature dependence of microbial growth laws

Although the effect of temperature on microbial growth has been widely studied, the role of proteome allocation in bringing about temperature-induced changes remains elusive. To tackle this problem, we propose a coarse-grained model of microbial growth, including the processes of temperature-sensitive protein unfolding and chaperone-assisted (re)folding. We determine the proteome sector allocation that maximizes balanced growth rate as a function of nutrient limitation and temperature. Calibrated with quantitative proteomic data for Escherichia coli, the model allows us to clarify general principles of temperature-dependent proteome allocation and formulate generalized growth laws. The same activation energy for metabolic enzymes and ribosomes leads to an Arrhenius increase in growth rate at constant proteome composition over a large range of temperatures, whereas at extreme temperatures resources are diverted away from growth to chaperone-mediated stress responses. Our approach points at risks and possible remedies for the use of ribosome content to characterize complex ecosystems with temperature variation.

Public capital, endogenous growth, and tax concession on savings

An endogenous growth model is developed where, on one hand income tax revenue is utilized to finance investment on public capital, and on the other hand tax concession is given on savings. If one of the two instruments—proportional income tax rate and proportional tax-concession rate on savings—is used as the policy variable to maximize the balanced growth rate while the other is treated as a parameter, an exogenous increase in the value of the parameter raises the optimum value of the policy variable and generates a positive effect on endogenous growth rate as well as on the rate of savings in the steady-state equilibrium.

A new impetus for endogenous growth: R&D offshoring via virtual labor mobility

AbstractWe develop a simple North–South model of quality ladders to show that the virtual mobility of labor across time zones, facilitated by the advance in communication technology, can raise the endogenous growth rate of the world economy. The unique balanced growth rate is increasing in the endowments of skilled labor in both countries and decreasing in the rate of impatience. Moreover, we find that partial R&D offshoring to the South has initially a negative effect on the level of skilled wages in the North, but this is compensated for by its positive effect on the growth rate in both North and South.

An analytical theory of balanced cellular growth

The biological fitness of microbes is largely determined by the rate with which they replicate their biomass composition. Mathematical models that maximize this balanced growth rate while accounting for mass conservation, reaction kinetics, and limits on dry mass per volume are inevitably non-linear. Here, we develop a general theory for such models, termed Growth Balance Analysis (GBA), which provides explicit expressions for protein concentrations, fluxes, and growth rates. These variables are functions of the concentrations of cellular components, for which we calculate marginal fitness costs and benefits that are related to metabolic control coefficients. At maximal growth rate, the net benefits of all concentrations are equal. Based solely on physicochemical constraints, GBA unveils fundamental quantitative principles of cellular resource allocation and growth; it accurately predicts the relationship between growth rates and ribosome concentrations in E. coli and yeast and between growth rate and dry mass density in E. coli.

ВЗАИМОСВЯЗЬ МЕЖДУ ЗАРАБОТНОЙ ПЛАТОЙ, ПРОИЗВОДИТЕЛЬНОСТЬЮ ТРУДА И КАЧЕСТВОМ ЧЕЛОВЕЧЕСКОГО КАПИТАЛА

The article assesses the dependence of wages on factors that have a predominant effect on wage dynamics. The cyclic relationship between wages, labor productivity and the quality of human capital is analyzed. The criteria for the effectiveness of strategic management are disclosed. The problems of reproduction of human capital are considered. The reasons for the decline in the quality of human capital due to the low level of wages in the Russian economy are revealed. The main directions of achieving balanced growth rates of labor productivity, wages and reproduction of human capital are identified.

Оцінювання збалансованості розвитку національної економіки: структурно-динамічний аспект

The work is devoted to the grounding of the scientific and methodological aspects and forming the practical recommendations for evaluation of national economy’s development balance. Assessment’s results are aimed at strict explanation of real economic dynamics to find relevant instruments and impact mechanisms to target national economic development to the mainstream. Structural and dynamic approach to the estimation gives an opportunity to neutralize the complexity of national economy as an object for the evaluation by means of building the phase portraits of national economic sectors’ movements in two-dimensional phase space structured with the balanced lines. Practicability of the “balanced growth concept” implementation as a part of the national economy’s balance development evaluating is scientifically proved. Using of the concept’s mechanisms and principles at the macro level of national economic systems’ evolution is proposed. The structural and logical schema of balanced indicators is formed. Empirical research of Ukrainian national economy’s balance development is done during 2008-2012’ period. Matrix of growth quality assessment is built for the main sectors of national economy. The conclusions about security, sustainability and expediency of national economic growth rates, its structural components are made. The national economy’s sectors characterized with the most sustainable and regular behavior according to assessment based on indicators of a Balanced Growth Rate and Sustainable Development Index are picked out. General results of balance and prospects of national economy’s development are formed.

On the analysis of endogenous growth models with a balanced growth path

This paper is the first that provides a comprehensive toolkit for analyzing deterministic, continuous-time, endogenous growth models with a balanced growth path. Since it is impossible to analyze the original dynamic system of growing variables, I suggest two different methods of transforming the model variables in order to derive a stationary system. The stationary system can then be used to test for the existence and uniqueness of transition paths and to derive transitional dynamics qualitatively (e.g. by phase diagram analysis) and quantitatively (e.g. by numerical simulation). I provide sufficient conditions under which the transformed dynamic system is autonomous, derive the functional form of the transformed system, and provide instructions of how to analyze the stability properties of the transformed system. Furthermore, I show that the class of models for which the method can be applied exhibits a specific pattern of transitional dynamics. Two identical economies that differ only with respect to the endowment of one state variable are shown to grow with the same balanced growth rate in the long-run, but at different levels.

Growth effects and welfare costs in an innovation-driven growth model of money and banking

This paper analyzes the effects of three distinctive monetary instruments, namely, the money growth rate, the required reserve ratio, and the leverage ratio, on growth and welfare in an R&D growth model with an active banking sector and financial frictions. Our analytical results show that increasing the money growth rate, required reserve ratio, and leverage ratio requirement have negative effects on the balanced growth rate. The relative magnitudes of their growth effects depend on the components of the banking capital structure that the monetary instruments can regulate and influence. Our calibration results show that the required reserve ratio gives rise to the most pronounced effects on economic growth and welfare costs, while the money growth rate has the least pronounced effects on both of them. Nevertheless, the extended analysis shows that the growth effects and welfare costs of the leverage ratio requirement may become the greatest if the costs arising from converting loans to production are substantially large. This implies that the choice of a better monetary instrument relies on banking efficiency. In the model, the welfare costs generated by the money growth rate can be larger than shown in previous studies due to the presence of financial frictions.

Government expenditure, external and domestic public debt, and economic growth

AbstractThis paper analyzes the relationship between government expenditure, tax on returns to assets, public debt, and growth in an endogenous growth model. Public debt is composed of two components, domestic debt and external debt. We show conditions for existence, uniqueness, and multiplicity of the steady states. More precisely, existence of steady state requires a sufficiently high productivity and a sufficiently low tax on returns to assets. We also provide the effects of an increase in the tax rate on returns to assets on the steady state. In particular, the relation between public spending and the tax rate has a bell shape. Domestic debt unambiguously increases with tax whereas external debt displays an inverted U‐shaped curve. A high tax rate leads to a reallocation of public debt in favor of domestic debt (to the detriment of external debt). The effect of taxation on consumption (and production) also displays a nonlinear pattern when the output elasticity of capital is lower than unity (the effect is monotonously increasing if this elasticity is unity). We also derive the conditions under which a tax increase can boost or reduce the balanced growth rate.