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In recent years, mathematical theories and tools specifically aimed at solving complex real-world problems and the consequent representation of models characterized by a certain degree of ambiguity, uncertainty and vagueness have assumed an increasingly important role in the landscape of pure and applied science disciplines. Among them, particularly Soft Set theory and Neutrosophic Set theory have revolutionized our ability to understand and model physical phenomena more accurately and they have consequently seen a growth in interest and research efforts as well as scientific production in their respective fields. [ABSTRACT FROM AUTHOR]

A new version of the model of the Russian banking system, which describes the dynamics of a wide range of indicators of banking activity, is presented. Compared to the previous version of the model, a breakdown of the volumes of ruble loans and deposits of businesses and households by maturity has been added. It is shown that the model makes it possible to accurately reproduce a wide range of performance indicators of the Russian banking system, outperforming the econometric analogs for most variables. [ABSTRACT FROM AUTHOR]

The purpose of the work is to study the foundations of a general risk theory. To form a single formal concept of risk, a number of definitions of the term “risk” found in the literature have been analyzed. There is a certain redundancy in the number of entities involved in the definition of this term. The necessary attributes of the genesis of this concept have been identified. Based on the analysis, using the instrumentation of modern algebra, a new formal, mathematically strict definition of risk is built. In fact, the paper proposes a new relational theory of risk, attracting only two entities to define the concept of “risk”: set and order of preference, inducing on this set the minimum structure of a semilattice or family of semilattices. The paper also describes an approach for studying in theoretical-risk setting problems in which there is no risk, in the traditional sense, in which the preference relation does not induce a semilattice and/or is a preorder. It is shown that in this case, when identifying a suitable equivalence relation on a set of outcomes, the problem can be reduced to a classical theoretical-risk setting. The second part of the paper contains an example of the direct use of a new relational risk theory in the study of nonnumerical economies. The problem of analysis of the situation of confrontation between two technologically unequal countries in game-theoretical staging is considered. We are talking about a grandiose space program - the organization of manned flights to Mars. The scales of the object of confrontation, the impossibility of quantitative assessments of the consequences of the implementation of scenarios of this project, make any quantitative assessments impossible at the stage of preliminary analysis. Therefore, only expert estimates of preferences at multiple outcomes can be used as initial data for confrontation analysis. Under these conditions, the emergence of certain risks of the project implementation for both players was demonstrated. During the analysis of the example illustrating the application of the new relational risk theory, a number of optimality principles considered in game theory were extended to the case when only partial orders are given on a set of game outcomes. As the methodological basis of the research we used the achievements of modern algebra, in particular the theory of relational systems, as well as the concepts and methods of game theory, such as representing the game in normal form, selecting dominant and eliminating dominant strategies, choosing solutions from many cautious strategies, as well as from the set of Nash Equilibria. The main result of the paper is the substantiation of relational risk theory, the formation of its conceptual base, the demonstration of the constructive nature of the theory on the example of solving a specific problem of risk analysis in an economic system described in terms of non-numerical characteristics. The material presented in the article is of interest to researchers in the field of risk theory and game theory, as well as to practitioners engaged in socio-economic and political forecasting in conditions of lack of information.

The Confucian doctrine of the Mean teaches that too much is as bad as too little. The Aristotelian doctrine of the Mean coincidently articulates that there can be too much or too little of nearly every human passion and action. In neoclassical economics, it is assumed that people tend to take any action at the optimal (not too much and not too little) level to maximise the net happiness from the action. This article argues that the Confucian doctrine of the Mean concurs with the optimality principle, and therefore that the optimality principle is a representation of human nature and can be understood as universal human wisdom. It follows that people can adopt both the Confucian doctrine of the Mean and the optimality principle as worldly common wisdom beyond the blunt dichotomy of spiritual orientalism and materialistic individualism. Too much emphasis on the technical differentials between the two has undermined the common wisdom embedded in them. [ABSTRACT FROM AUTHOR]

Wireless sensor networks (WSNs) find their application in as diverse fields as collection of data for weather forecasting to detection of enemy activities by defense agencies. Considering the diverse and sensitive areas where WSNs are deployed, un-interrupted and timely delivery of data is as important as energy efficient delivery. This necessitates the requirement of a routing protocol that takes into account both the energy consumption and system delays while finding the best route to deliver packet/data from node to sink. In literature, a number of shortest path based algorithms viz. dikshatra, bellman ford, A*, floyd–warshall's and heuristic search based algorithms viz. Ant colony optimization (ACO), particle swarm optimization, evolutionary algorithms reinforcement learning have been proposed for enhancing the routing efficiency. ACO which is one of the heuristic search algorithms has proven to more efficient for routing methods due to its dynamic and flexible nature. In most of the ACO based routing algorithms total energy consumption and delay incurred by a path have been considered as two main optimization parameters for finding the optimal path between source and sink. However, due to little difference in the respective optimization parameters of different available paths, the convergence time of these algorithms is very high, which results in longer set up delay and higher energy consumption. In this paper, an ACO based routing algorithm has been proposed which considers excess energy (excess energy is that part of communication energy expenditure, which is used to move packet in direction perpendicular to the line of sight direction between source and destination) as one of the optimization parameters. The use of excess energy consumption as route selection parameter leads to faster convergence of the algorithm as well as results in finding more energy and delay efficient path. The proposed method has been simulated and compared with state-of-the-art ACO based routing methods i.e. deflection angle based ACO algorithm and E&D ANTS algorithm. The simulation results indicate that the proposed method has low convergence time, balanced energy consumption, lower time delay, high packet delivery ratio and leads to longer network lifetime. [ABSTRACT FROM AUTHOR]

We propose a description and explanation of a heuristic approach that can be used in applied dynamic economic models containing agent optimization problems. Solving such problems, we can obtain a system containing differential and algebraic equations, inequalities, and complementary slackness conditions. These conditions significantly complicate the analysis of such models even at the calibration stage. We show that the natural assumption about the alternation of regimes defined by the method of the resolution of the complementary slackness conditions allows us to pass to relations that are more regular and convenient from the point of view of the model's calibration. [ABSTRACT FROM AUTHOR]

Objective To investigate hemodynamic stresses on anterior cerebral artery bifurcation apex and possible mechanism of the optimality principle in protecting bifurcation wall from supercharged hemodynamic stresses. Methods Three-dimensional angiographic datasets of 122 patients with anterior communicating artery (Acom) aneurysms, 21 patients with non-Acom aneurysms, and 220 control subjects with no aneurysms were used. Radii of parent (r 0) and daughter branches (r 1 and r 2) were measured, and bifurcations obeying the optimality principle required optimal caliber control of r 0 n = r 1 n + r 2 n, with the junction exponent n approximating 3. Radius ratio = r 0 3/(r 1 3 + r 2 3) and n were compared between aneurysmal and control bifurcations. Blood flow was simulated for analysis of hemodynamic stresses. Results Acom bifurcations in subjects without Acom aneurysms displayed optimal caliber radius, with mean radius ratio of 0.99 and n of 3.25, whereas Acom aneurysmal bifurcations had significantly lower radius ratio, 0.62 (P < 0.05), but higher n, 4.23 (P < 0.05). Peak wall shear stress and corresponding total pressure were significantly smaller for bifurcations obeying than disobeying the optimality principle (P < 0.001 and P < 0.05, respectively). Total pressures in the direct impinging center, peak wall shear stress distance, and anterior cerebral artery bifurcation angle all were significantly smaller for bifurcations obeying than disobeying the optimality principle (P < 0.05 and P < 0.001, respectively). Conclusions Normal anterior cerebral artery bifurcations obey the optimality principle whereas bifurcations with Acom aneurysms do not. Disobeying the optimality principle presents significantly enhanced hemodynamic stresses to possibly damage the bifurcation wall for aneurysm initiation. Highlights • The optimality principle decreases hemodynamic stresses for aneurysm initiation at bifurcations. • Normal ACA bifurcations obey the optimality principle. • The ACA bifurcation with aneurysms does not obey the optimality principle. [ABSTRACT FROM AUTHOR]

The paper develops the solution to the problem of axiomatic definition of the maxmin expected utility decision criteria under uncertainty. The axiomatic description of the corresponding preference relation is proposed. It is based on the specific form of the principle of guaranteed result. [ABSTRACT FROM AUTHOR]

In this paper we analyze the reinforcement of blood vessels by collagen fibers using the concept of netting analysis from composite theory. To this end, we interpret preferred fiber reinforcement as the solution to a weighted optimization problem having two competing targets, minimal pulse pressure and minimal material usage, under the constraint of mechanical stability against buckling in a physiologically reasonable range of blood pressures. We demonstrate that the solution to this optimization problem for large arteries is a helical reinforcement with fibers oriented diagonally and for small arteries and veins an orthogonal reinforcement consisting of axial and circumferential fibers. Both findings agree well with experimental data reported by others, which suggests the existence of an underlying mechanical principle for the establishment and maintenance of vascular fiber orientations under normal conditions. [ABSTRACT FROM AUTHOR]

• How plants respond to climate change is of major concern, as plants will strongly impact future ecosystem functioning, food production and climate. Here, we investigated how vegetation structure and functioning may be influenced by predicted increases in annual temperatures and atmospheric CO2 concentration, and modeled the extent to which local plant-plant interactions may modify these effects. • A canopy model was developed, which calculates photosynthesis as a function of light, nitrogen, temperature, CO2 and water availability, and considers different degrees of light competition between neighboring plants through canopy mixing; soybean (Glycine max) was used as a reference system. • The model predicts increased net photosynthesis and reduced stomatal conductance and transpiration under atmospheric CO2 increase. When CO2 elevation is combined with warming, photosynthesis is increased more, but transpiration is reduced less. Intriguingly, when competition is considered, the optimal response shifts to producing larger leaf areas, but with lower stomatal conductance and associated vegetation transpiration than when competition is not considered. Furthermore, only when competition is considered are the predicted effects of elevated CO2 on leaf area index (LAI) well within the range of observed effects obtained by Free air CO2 enrichment (FACE) experiments. • Together, our results illustrate how competition between plants may modify vegetation responses to climate change. [ABSTRACT FROM AUTHOR]