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The goal of this paper is to present two novel approaches to teaching the components of and use of free body diagrams (FBDs) in core mechanical engineering courses at the Rochester Institute of Technology (RIT). The first technique is a mnemonic device to remember the key components of FBDs. This device is referred to as "The ABC's of FBDs". It uses the first four letters of the alphabet to identify required FBD components. The second pedagogical method developed and implemented is a game based off of "Paper Telephone". The game emphasizes the connection between the FBD and the equations of equilibrium. At this point, these devices have only been utilized for 3 semesters however, anecdotal evidence indicates that the inclusion of these devices has aided in the retention of FBD components in follow on courses. [ABSTRACT FROM AUTHOR]

In the paper, an equilibrium problem for an elastic body with a crack crossing a thin inclusion at some point is analyzed. As a result, the crack divides the inclusion of two parts. One part of the inclusion is a rigid and the other is an elastic. The elastic inclusion is modeled by a Bernoulli – Euler beam. The conjugation conditions of these inclusions at a given point are considered. To exclude a mutual penetration between inclusions, inequality type boundary conditions are imposed. Nonlinear boundary conditions are also considered at the crack faces.The main goal of the paper is to justify a passage to the limit as the rigidity parameter of the thin inclusion goes to infinity. [ABSTRACT FROM AUTHOR]

The article presents abstracts pertaining to organization development and change including "Toward a Process Model of Strategic Change in Multinational Enterprises, "Do Humanistic Values Matter?," and "Reframing Change in Organizations: The Equilibrium Logic and Beyond."

Here, in this paper, the spatial motions of a boundless collisionless electron Vlasov-Poisson gas were considered in a three-dimensional Cartesian coordinate system. Using the replacing of independent variables in the form of hydrodynamic substitution, a transition was made from the kinetic equations to an infinite system of gas-dynamic equations in the "vortex shallow water" and the Boussinesq approximations. In the process of proving the linear instability for the exact stationary solutions to the Vlasov-Poisson equations, the well-known sufficient Newcomb-Gardner-Rosenbluth condition for stability of these solutions with respect to one incomplete unclosed particular class of small spatial perturbations was reversed. An original linear differential second-order inequality with constant coefficients for the Lyapunov functional was also obtained. When the sufficient conditions found in this paper for the linear practical instability of the exact stationary solutions under research are satisfied, an a priori exponential estimate from below for the growth of small three-dimensional perturbations follows from this inequality. Since the estimate was derived without any additional restrictions on the exact stationary solutions under study, then, in this way, the absolute linear instability for the spatial dynamic equilibrium states of the electron Vlasov-Poisson gas with respect to three-dimensional perturbations was proved. [ABSTRACT FROM AUTHOR]

Pricing plays an important role in any market competition, but particularly in those businesses that hold a seat in hyper competitive economic activities such as hotels. This paper analyses a market competition between one corporate social responsibility (CSR) hotel and one for profit (FP) hotel, in which both hotels set room prices. We study three different market behaviors: (i) both hotels take their decisions simultaneously; (ii) the CSR hotel takes the leader position; (iii) the FP hotel takes the leader position. For each situation, by using game theory techniques, we compute the different outcomes of the model at equilibrium. We also describe the effects of CSR on the outcomes. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the multistability of a non-smooth model having infinite number of equilibrium points. The three-dimensional model is in a form of a system of nonlinear ordinary differential equations including a non-smooth function. The influence of initial conditions is considered while observing coexistence of multiple attractors. To obtain such phenomena, the Newton's method is applied to find the initial conditions which lead to a periodic orbit near the chaotic attractor. By perturbing the initial conditions around this point, nearby points are found using the 0-1 test for chaos, for which the system exhibits regular and chaotic behavior. Curiously, isolated grid points of initial conditions are detected, leading to the periodic orbit, remaining isolated under magnification. These are surrounded by initial conditions tending to chaotic attractors. [ABSTRACT FROM AUTHOR]

In this paper, the stability for three-dimensional (3D) states of dynamic equilibrium of the two-component Vlasov-Poisson plasma was studied. Using the direct Lyapunov method, it was proved that the spatial dynamic equilibria of the Vlasov-Poisson plasma with respect to small 3D perturbations are absolutely unstable. For the spatial states of dynamic equilibrium of the two-component Vlasov-Poisson plasma, the sufficient conditions for linear practical instability were obtained. The a priori exponential lower estimate was constructed, and the initial data for small 3D perturbations which are growing with time were characterized. [ABSTRACT FROM AUTHOR]

In this paper, we study a stochastic variant of the Li-Rinzel model of calcium oscillations. A bifurcation analysis of the model is carried out, parametric zones of equilibrium and oscillatory regimes are described, basins of their attraction and separatrices detaching these basins are constructed. A probabilistic description of the frequency and amplitude characteristics of calcium oscillations under conditions of parametric random disturbances is given. The phenomena of stochastic excitability and generation of oscillations of mixed modes are described. [ABSTRACT FROM AUTHOR]

This paper considers sequential decisions in a quantity-setting mixed market with emission tax. We analyse two different situations: (i) The public firm as being the leader; and (ii) the private firm as being the leader. We compare the results obtained in these two combinations, By also comparing the results got in previous literature for the simultaneous decision case, we conclude that the equilibrium emission tax is the lowest when the public firm is the leader. Throughout the paper we present other results. [ABSTRACT FROM AUTHOR]

This paper proposes a non-classical theory of stressed plates. Resolving equations are obtained in terms of longitudinal forces of shear forces and internal moments, and boundary conditions are formulated. The obtained solutions simultaneously satisfy the equilibrium equations and the Beltrami-Mitchell stress compatibility equations. A boundary value problem is formulated for a plate under the action of mutually balanced loads. Some applied problems have been solved. [ABSTRACT FROM AUTHOR]

This paper studies the presence of collinear and out of plane equilibrium points in the elliptic restricted four body problem under the influence of radiation pressure and oblateness effects. It also deals with the linear stability of the equilirium points. We have assumed that three primaries are moving in elliptic orbits around their common center of masses which is assumed to be the origin of the coordinate system. Primaries are positioned at the vertices of an equilateral triangle while the fourth body of the system is assumed to be infinitesimally small in size. It was observed that for this system, we have two collinear and two or four out of plane equilibrium points exists which is depend on true anomaly of the orbit. The position of the out of plane equilibrium points obtained on the x-z plane are found to be in symmetrically aligned with respect to x-y plane. It was observed that both the collinear and out of plane equilibrium points are linearly unstable. The fractal Basin for out of plane equilibrium points were studied. [ABSTRACT FROM AUTHOR]

Bar elements pretensioned by unbonded steel reinforcement placed in narrow ducts are considered in this paper. Such elements find one of their main applications in the field of post-tensioned reinforced concrete. One of the main features of the post-tensioned concrete beams is an interaction between pretensioned strand and rest of the construction body which appears like a distributed balancing load. Increasing of the beam deflection leads to tensioning force change in its strands. This affects to the balancing load that in turn differs the subsequent deflection increasing. Analysis of influence of changing balancing load to equilibrium of cross sections of simply supported post-tensioned reinforced concrete beam has been made in the proposed article by methods of applied mechanics of materials. It is shown that increasing deflection of the beam and corresponding growth of balancing load are compensated by bending moment caused by eccentrical compression of the beam. [ABSTRACT FROM AUTHOR]

The paper studies the behavior of a pivotally supported rod, the ends of which are fixed in the longitudinal direction under the action of a compressive load. The stability of a centrally compressed rod with an incompressible axis is considered if transverse reactions occur during buckling that are proportional to its deflections. It is assumed that these reactions are distributed along a vertical axis parallel to the axis of the rod and are determined by the coordinates in three-dimensional space x, y, and z. The equations are used, taking into account which it is possible to study the buckling of the rod in the case when the axis around which the cross sections rotate during the buckling does not shift. The condition is assumed that if the compressive force differs little from the critical load, then the resulting curved form of the rod equilibrium differs little from the rectilinear one, and the usual approximate expressions can be used to express the curvature. It is shown that in this case, the buckling of the rod in the planes of symmetry does not depend on torsion. When studying the stability of the rod under the action of end forces, it is shown that even in the first approximation, the results are close to the exact solution of F. S. Yasinsky. The stability of the supported rod is analyzed when the intensity of the longitudinal compressive load changes according to a linear law. The author believes that buckling occurs at a non-deformable surface. [ABSTRACT FROM AUTHOR]

Finding the ‘right’ balance between centralization and decentralization in organizational processes, governance, and IT can be difficult. To navigate this tension field, organizations need to find (de)centralization equilibria that are often dynamic and depend on organizational strategy and context. However, little is known about how organizations should respond once an old equilibrium is punctuated or breaks down. In this paper, we thus conduct an inductive multiple-case study to investigate how organizations sustain and transition between (de)centralization equilibria. We synthesize our insights into a process model that paints the transition as an iterative recalibration process subject to centralization and decentralization tensions. Often, this process will require local and temporary compromises. Our work contributes a muchneeded process perspective to the IS literature on (de)centralization. [ABSTRACT FROM AUTHOR]

A Cournot duopoly is a market dominated by two firms with profit maximization as their goal. An alternative to the profit maximization model is the constraint profit maximization model, where firms maximize their profits subject to minimum sales constraints. In this paper, a duopoly model with isoelastic demand function and homogeneous product is considered. The local stability condition of the Cournot equilibrium in the cases of sales constraint and no sales constraint were obtained. Initial results implied that it is easier for the duopoly model to be stable if firms impose some minimum constraints on their sales. [ABSTRACT FROM AUTHOR]

Crowdsourcing is an emerging phenomena based on outsourcing the work to undefined large network of individuals by means of open call requesting for participation. It has started to gain much more attention in software engineering research areas, from coding to development by means of special platforms and applications. It is seen as a good alternative for academia and industry as a means of software development approach. Crowdsourcing is believed to enhance efficiency of the projects and reduce their development times and costs. Besides, it is possible to find a large number of people/community who are willing to work for crowdsourced projects at any time. This paper focuses on the demand models in the crowdsourcing platform, where crowd members and requestor firms get together. In this platform, both sides need to satisfy from their received profits; either from the gained prize or received software product. In this paper, we first introduce crowdsourcing concepts in software engineering and then concentrate on the demand models. [ABSTRACT FROM AUTHOR]

This paper studies the optimal component procurement structures of two competing OEMs that rely on a joint contract manufacturer to produce two partially substitutable products. The contract manufacturer, in turn, needs to procure its components from a supplier. We investigate whether the OEMs should delegate component procurement to the contract manufacturer or control it when contracts are unobservable. When the supplier has pricing power, we show that under procurement control, all supply chain members might benefit from contract unobservability if the downstream market competition is moderate, while under delegation, all supply chain members benefit from contract unobservability unless the market competition is extremely fierce. We also demonstrate that component procurement control for both OEMs arises as the equilibrium, in contrast to the observable case. When the supply market is competitive, we show that both OEMs prefer to delegate their component procurement to the contract manufacturer to benefit from the discount aggregation. While procurement control might also emerge as an equilibrium, we show that it is Pareto dominated by the delegation strategy. We develop a new theory to explain different procurement strategies adopted by OEMs to procure different types of components, uncovering the informational role of different procurement structures under unobservable contracts as it shapes the equilibrium procurement structure. [ABSTRACT FROM AUTHOR]

Many two-sided marketplaces rely on match recommendations to help customers find suitable service providers at suitable prices. (Examples include Angi, HomeAdvisor, Thumbtack and To8to.) This paper develops a tractable methodology that a platform can use to optimize its match recommendation policy so as to maximize the total value generated by the platform while accounting for the endogeneity of transaction prices, which are determined by the providers and can depend on the platform's match recommendation policy. Despite the complications due to price endogeneity, an optimal match recommendation policy can be computed efficiently using stochastic subgradient descent. Under additional regularity conditions on the distribution of preferences, an optimal policy has a simple form: for each customer segment and each provider, the platform has a certain target on the rate that the provider is recommended to this segment. Any policy that achieves these targets is optimal. Finally, accounting for the endogeneity of prices is crucial: if the platform were to optimize its match recommendations while erroneously assuming that prices are exogenous, then the market is likely to get stuck at a strictly sub-optimal equilibrium, even if the platform were to continually re-optimize its match recommendation policy after prices re-equilibrate. Link to full paper: https://ssrn.com/abstract=4034950 [ABSTRACT FROM AUTHOR]

The theory of repeated games offers a compelling rationale for cooperation in a variety of environments. Yet, its consequences for collective decision-making have been largely unexplored. In this paper, we propose a general model of repeated voting and study equilibrium behavior under alternative majority rules. Our main characterization reveals a complex, non-monotonic, relationship between the majority threshold, the preference distribution, and the optimal equilibrium outcome. In contrast with the stage-game equilibrium, the optimal equilibrium of the repeated game involves a form of implicit logroll, individuals sometimes voting against their preference to achieve the efficient decision. In turn, this affects the optimal voting rule, which may significantly differ from the optimal rule under sincere voting. The model provides a rationale for the use of unanimity rule, while accounting for the prevalence of consensus in committees which use a lower majority threshold. The full version of the paper is available at: https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4114079 [ABSTRACT FROM AUTHOR]

Analysis of the temperature effect on the mechanical characteristics by the molecular dynamics method has received much consideration in the world science. Though many authors investigate the mechanical properties and fracture of copper nanowires at different temperatures, the meso-analysis and analysis of surface and volume atom subsystems are missing, which radically disables to study the temperature effect on the fracture stages, whereas this is a key feature of this paper. In this paper, the entire system was first cooled, which led it into the thermodynamically equilibrium state. Then, this equilibrium system was heated up to the desired temperature, and necessary characteristics of the system were analyzed. [ABSTRACT FROM AUTHOR]

In this paper, we consider a system of two coupled populations modeled by the Ricker map. Isolated subsystems can be in various stable states: equilibrium, periodic, and chaotic. If maps are coupled, the behavior of the system can change significantly, for example, the equilibrium is transformed into a periodic regime, and the chaotic regime changes to order and vice versa. In this study, a parametric analysis of possible scenarios of changing corporate dynamics and their connection with bifurcations of various types is carried out. Phase portraits of the system, bifurcation diagrams, attractors and their basins are analyzed. [ABSTRACT FROM AUTHOR]

Radial integration operators Iα in bounded star–shaped domains are used in mathematical physics to find solution of biharmonic equation, proving of S.L. Sobolev embedding theorems, in the theory of special functions, etc. In this paper, we introduce the new operator Jα acting on functions defined in complements Ω of a star–shaped domains. By means of these operators three–dimensional quaternionic Kolosov–Muskhelishvili formulae in Ω is obtained. As application, the problem of an equilibrium of three dimensional elastic space with a ball cavity is solved in a closed form. [ABSTRACT FROM AUTHOR]

The energy source known as natural gas can be regarded as the fuel that enables us to transition to a future with lower carbon emissions while meeting the massive demand for energy. There are several attractions to conserving natural gas as hydrates, including the incredible capacity to store multiple volumes in hydrate crystals. Being eco-conscious, non-explosive, and providing a compact method of natural gas storage with a high volumetric storage capacity, clathrate hydrates are a highly advantageous form of natural gas storage. When they develop in oil-gas pipes and obstruct flow, gas hydrates are an industry annoyance that creates problems with flow assurance. It is crucial to forecast the gas hydrate formation conditions to make the most of the potential for storing natural gas as clathrate hydrates and tackle hydrate-related issues in the gas and oil sector. This paper analyzes some of the available empirical correlations from the literature and is then compared using statistical tools to obtain the optimum one to compute the equilibrium state points of methane (CH4) hydrate in pure water for storage applications. The suggested empirical correlations are analyzed for a collection of pressure from 2.641 to 299 MPa and temperatures between 273.2–317.2 K. [ABSTRACT FROM AUTHOR]

The paper consists of a method to implement a control system algorithm for an inertia wheel inverted pendulum. Like any control system application, the transfer function of the plant should be known in order to design the proper controller. The key point of this paper is that the behaviour of the plant is consider unknown, so a system identification should be done at first. Even if the classical way to obtain the transfer function is by writing the physical equations, the result obtained from system identification covers the errors that might miss from the theoretical model. PID was chosen as control algorithm because, once implemented, it can be easily adjusted. The performance criteria for this system is the angular range of functionality, the stability in the equilibrium position and the sensitivity to external mechanical perturbations. [ABSTRACT FROM AUTHOR]

To better understand discriminations and the effect of affirmative actions in selection problems (e.g., college admission or hiring), a recent line of research proposed a model based on differential variance. This model assumes that the decision-maker has a noisy estimate of each candidate's quality and puts forward the difference in the noise variances between different demographic groups as a key factor to explain discrimination. The literature on differential variance, however, does not consider the strategic behavior of candidates who can react to the selection procedure to improve their outcome, which is well-known to happen in many domains. In this paper, we study how the strategic aspect affects fairness in selection problems. We propose to model selection problems with strategic candidates as a contest game: A population of rational candidates compete by choosing an effort level to increase their quality. They incur a cost-of-effort but get a (random) quality whose expectation equals the chosen effort. A Bayesian decision-maker observes a noisy estimate of the quality of each candidate (with differential variance) and selects the fraction α of best candidates based on their posterior expected quality; each selected candidate receives a reward S. We characterize the (unique) equilibrium of this game in the different parameters' regimes, both when the decision-maker is unconstrained and when they are constrained to respect the fairness notion of demographic parity. Our results reveal important impacts of the strategic behavior on the discrimination observed at equilibrium and allow us to understand the effect of imposing demographic parity in this context. In particular, we find that, in many cases, the results contrast with the non-strategic setting. We also find that, when the cost-of-effort depends on the demographic group (which is reasonable in many cases), then it entirely governs the observed discrimination (i.e., the noise becomes a second-order effect that does not have any impact on discrimination). Finally we find that imposing demographic parity can sometimes increase the quality of the selection at equilibrium; which surprisingly contrasts with the optimality of the Bayesian decision-maker in the non-strategic case. Our results give a new perspective on fairness in selection problems, relevant in many domains where strategic behavior is a reality. [ABSTRACT FROM AUTHOR]

When allocating indivisible items across agents, it is desirable for the allocation to be envy-free, which means that each agent prefers their own bundle over every other bundle. Even though envy-free allocations are not guaranteed to exist for worst-case utilities, they frequently exist in practice. To explain this phenomenon, prior work has shown that, if utilities are drawn from certain probability distributions, then envy-free allocations exist with high probability (as long as the number of items is sufficiently large relative to the number of agents). In this paper, we study a more general setting, a smoothed model of utilities, in which utility profiles are mainly worst-case, but are slightly perturbed at random to avoid brittle counter-examples. Specifically, we start from a worst-case profile of utilities and, with some small probability, increase an agent's value for an item by adding a random amount, where the probability of perturbation and the distribution of perturbations are parameters of the model. If the probability of such perturbations is sufficiently large relative to the number of agents and items, we show that envy-free allocations exist with high probability and can be found efficiently. This analysis is tight up to constant factors. We also give an efficient algorithm for finding allocations that are simultaneously proportional and Pareto-optimal, which succeeds with high probability in the smoothed model. [ABSTRACT FROM AUTHOR]

This paper shows the existence of nonautonomous projected dynamical systems in Hilbert spaces. These systems arise most recently in the work being done on evolutionary variational inequalities (EVI) and help in extending the mix between the dynamics given by EVI and the disequilibrium evolution of equilibrium problems. This paper fills a gap in the current study of dynamic evolution of equilibrium problems. [ABSTRACT FROM AUTHOR]

This paper presents a 4D hyperchaotic system with two unstable saddle-foci equilibria which is constructed by combining a 3D chaotic system with a 1D linear system utilizing a coupling control strategy. The proposed system is characterized by one exponential term and consists of eight terms. Some of the dynamic behaviors of this system have been analyzed theoretically and numerically through simulation such as equilibria points, Lyapunov exponents, Kaplan-York dimension, Multistability, chaos control, and chaos synchronization. The proposed controls were implemented theoretically through the Lyapunov stability theorem and the numerical simulation confirmed the accuracy and validity of our theoretical results. [ABSTRACT FROM AUTHOR]

We modify a theory of flow stress introduced in [6,7,8] for a class of polycrystalline materials with equilibrium and quasy-equilibrium defect structure under quasi-static plastic deformations. We suggest Maxwell-like distribution law for defects (within dislocation-disclination mechanism) in the grains of polycrystalline samples with respect to grain's diameter. Polycrystalline aggregates are considered within single-and two-phase models that correspond by the presence of crystalline and grain-boundary (porous) phases. The scalar dislocation density is derived. Analytic and graphic forms of the generalized Hall–Petch relations for yield strength are produced for single-mode samples with BCC (a-Fe), FCC (Cu, Al, Ni) and HCP (a-Ti, Zr) crystal lattices at T=300 K with different values of the grain-boundary phase. We derived new form of the temperature-dimensional effect. The values of extremal grain and maximum of yield strength are decreased with raising the temperature in accordance with experiments up to UFG region. [ABSTRACT FROM AUTHOR]

The paper conserns to the problem of the equilibrium of a two-dimensional viscoelastic body having delaminated thin elastic inclusion. The formulation of the problem contains nonlinear conditions of inequality-type on the fracture curve as on a part of the boundary. This causes formulation of the problem in the form of variational inequality. The existence and uniqueness of solution of the problem is proved. The case of a thin rigid inclusion in a viscoelastic body is considered and it is shown that the problem of rigid inclusion is a limiting case for a family of problems on thin elastic inclusions as the stiffness parameter of the inclusion goes to infinity. [ABSTRACT FROM AUTHOR]

The objective of this paper is to establish the existence and uniqueness of the solution of (EP) by generalizing a new class of trifunction equilibrium problems in the setting of Banach space. Furthermore, we consider trifunction as special cases of 퐸푝(훽1, 훽2) and find new conditions under which the equilibrium state holds using βh- monotone subsets and especially in convex and closed subsets (bounded or unbounded). In so doing, we are able to ensure the existence and uniqueness of the solution of (EP), thus improving latest properties in its literature. We are also interested in obtaining optimization as a particular case of 퐸푝(훽1, 훽2). [ABSTRACT FROM AUTHOR]

The problem of the ecological system long-term keeping near the equilibrium position with minimization of control resources is considered. A mathematical formulation of this problem and a method for optimal expenditure control constructing are presented. While deviations from the equilibrium point are very small, its controlled dynamics can be described by linear differential equations with constant coefficients. The control actions are modeled by piecewise-constant unidirectional functions with a finite number of switching points. The choice of this control class is due to the characteristic features of environmental tasks: control actions on living systems are unidirectional and often have a periodic character [3], [5-11]. It can be individuals catching from the population, feeding, watering, thinning, etc. Therefore, the chosen control class takes into account both the unidirectionality and the periodicity of the control actions. Two types of regulation are discussed: adding to the system any substances promoting the population growth (substrates, fertilizers, etc.), and removal of any volumes (catching individuals from the population, thinning, etc.). As a minimizable functional, the expenditure criterion is used, that is proportional in practice to the consumption of resources used for controlling [1], [4]: pesticides, fertilizers, medicines, etc. In some cases, this criterion minimizing, in addition to the economic one, also gives a direct environmental effect. For example, the constructed optimal control allows the pest population to be destroyed with the minimum quantity of toxic chemicals that adversely affect the environment. The method for solving the problem is based on the mechanical systems optimal control problems methods of solution developed by the authors (e.g. [2]). In this paper, taking into account the ecological specifics of the problem, the system of transcendental equations is obtained. Numerical solution of this system allows us to find the control switching points that satisfy the necessary conditions of the expenditure criterion extremum. To find an adequate initial approximation for the standard numerical methods for solving the equations system an original algorithm is presented. [ABSTRACT FROM AUTHOR]

This paper briefly describes an approach to assure robustness of a dynamic system. Its primary focus is on robust stability, not robust performance, in the presence of parameter variations and model uncertainties. The proposed control scheme makes use of catastrophe functions with three control factors and two behavior axes. Based on our analysis, the paper presents the conditions for converging to an equilibrium point and explains how to implement a controller to achieve robust stability. As a practical case, design of a control system for a robotic manipulator and the corresponding numerical simulations are presented. The results indicate that the range of robust stability can be extended using the proposed approach. [ABSTRACT FROM PUBLISHER]

In this paper, we study the existence of equilibrium in non-cooperative game with fuzzy parameters. We generalize te results of Larbani and Kacher(2008, 2009) in infinite dimentional spaces. The proof is based on the Browder-Fan fixed point theorem. [ABSTRACT FROM AUTHOR]

In this paper we propose distinct approach for numerical simulation of the mechanical system's dynamics in the entropy formalism, as opposed to the canonical energy formalism. It was shown that this approach allows one to reproduce any pre-specified equilibrium distribution, and the monotonicity of the entropy increase indicates the general physical correctness from the thermodynamic point of view. [ABSTRACT FROM AUTHOR]

This paper discussed SIR-UV model of dengue spread considering the effect of hospitalization which involves human and mosquito compartments, and then this model will be simplified by using Quasi-Steady State Approximation (QSSA). In this model, there will be two types of equilibrium points, and they are Diseases-Free Equilibrium and Endemic Equilibrium. Basic reproduction number will also obtain from this model, which is the threshold whether the diseases is said to be endemic or not in the population. In addition, sensitivity analysis of the basic reproduction number will also be obtained, as well as simulation of the model for each case that describes the behavior and stability around the equilibrium point. Our numerical results on the sensitivity of the basic reproduction number and the autonomous simulation indicate the success of hospitalization to prevent dengue should consider the level of hygiene of the hospital. More hygiene the hospital, higher the possibility that hospitalization success to prevent dengue spread. [ABSTRACT FROM AUTHOR]

The presumed connection between causal ambiguity and sustained, capabilities-based performance advantages is well-known to strategy researchers. This paper presents the first formal examination of this connection. I provide a precise distinction between the intrinsic, or potential, level of causal ambiguity associated with a particular strategy and the actual level that obtains in equilibrium. I find that intrinsic ambiguity is a necessary but, contrary to the speculation of some, insufficient condition for a sustained capability-based advantage. Most importantly, I also find that the complexity of the network of causal relations induced by a firm's strategy is not positively correlated with its intrinsic level of ambiguity. This contradicts earlier conjectures that have found their way into mainstream thinking. [ABSTRACT FROM AUTHOR]

In many social contexts, individuals choose a set of social interactions to maximize their private benefit, but the resulting social network structure is a public phenomenon that affects all members of the network. This paper builds on previous research by the authors (Lazer and Friedman 2005), which found that under certain circumstances efficient collaborative networks (e.g. small world networks) yield poor system-wide results. In this paper, we assume that the structure and efficiency of the network is endogenous, the result of an evolutionary process where "networking strategies" that yield greater success for agents will eventually dominate the system. Results of an agent-based model show that while sparse networks perform better in the long run because they maintain diversity, individual actors that are well connected systematically do better than poorly connected actors. The long run equilibrium is a highly connected network, through which information flows rapidly, wiping out diversity, and resulting in a poorly performing system. The "tragedy of the network" is that if everyone acts in their best interest, the resulting network will be worse for everyone. ..PAT.-Unpublished Manuscript [ABSTRACT FROM AUTHOR]

We study the problem of finding optimal correlated equilibria of various sorts: normal-form coarse correlated equilibrium (NFCCE), extensive-form coarse correlated equilibrium (EFCCE), and extensive-form correlated equilibrium (EFCE). This is NP-hard in the general case and has been studied in special cases, most notably triangle-free games[2], which include all two-player games with public chance moves. However, the general case is not well understood, and algorithms usually scale poorly. In this paper, we make two primary contributions. First, we introduce the correlation DAG, a representation of the space of correlated strategies whose structure and size are dependent on the specific solution concept desired. It extends the team belief DAG of Zhang et al. [3] to general-sum games. For each of the three solution concepts, its size depends exponentially only on a parameter related to the information structure of the game. We also prove a fundamental complexity gap: while our size bounds for NFCCE are similar to those achieved in the case of team games by Zhang et al. [3], this is impossible to achieve for the other two concepts under standard complexity assumptions. Second, we propose a two-sided column generation approach to compute optimal correlated strategies in extensive-form games. Our algorithm improves upon the one-sided approach of Farina et al. [1] by means of a new decomposition of correlated strategies which allows players to re-optimize their sequence-form strategies with respect to correlation plans which were previously added to the support. Experiments show that our techniques outperform the prior state of the art for computing optimal general-sum correlated equilibria, and that our two families of approaches have complementary strengths: the correlation DAG is fast when the parameter is small and the two-sided column generation approach is superior when the parameter is large. For team games, we show that the two-sided column generation approach vastly outperforms standard column generation approaches, making it the state of the art algorithm when the parameter is large. Along the way, we also introduce two new benchmark games: a trick-taking game that emulates the endgame phase of the card game bridge, and a ride-sharing game, where two drivers traversing a graph are competing to reach specific nodes and serve requests. The full version is available at: https://arxiv.org/abs/2203.07181 [ABSTRACT FROM AUTHOR]

Unfortunately, the classical formulation of the problem of the theory of elasticity in stresses consists in solving three equilibrium equations when three static boundary conditions are meet. In this paper, based on the correct formulation of the stress problem for six Beltrami-Mitchell equations when three boundary-line equilibrium equations and three static boundary conditions are satisfied, solutions of stress problems in an approximate analytical form are obtaining. The limiting cases of a parallelepiped in the form of a rod and a plate are considered. [ABSTRACT FROM AUTHOR]

Variational problems for composite plates with a system of joined rigid inclusions are considered. It is supposed that plate consist of an elastic matrix and cylindrical rigid inclusions. Inclusions are joined at common fibers so that displacements of these joined inclusions coincide at the corresponding points of fibers. Variational approach is used in order to deal with the Signorini-type boundary condition that describes mutual nonpenetration of opposite crack faces. We study two types of equilibrium models that correspond to different types of rigid inclusions. For the first model, we suppose that the plate has a volume rigid inclusion which is described by a corresponding 3D domain, and the second one describes the body containing a set of fastened thin rigid inclusions, each of which corresponds to a cylindrical surface. The crack is defined by the same curve in both models so that crack curve lies on the part of the boundary of the volume inclusion. An optimal control problem is formulated in the framework of the both model, such that a control is specified by the number of thin rigid thin plane inclusions and by the limiting case which as it turned out, fits to the first model. A quality functional is defined by an arbitrary continuous functional in a suitable Sobolev space. The solvability of the optimal control problem is proved. [ABSTRACT FROM AUTHOR]

In this paper, we proposed and analyzed the Omnivore -predator-prey model with the II-Holling functional response to the interaction between Predator-Prey and the Nonlinear functional response to the interaction between Omnivore–prey, existence, uniqueness, and boundedness of solution of the system are studied. All equilibria points in the system coexist. local stability and local bifurcation are investigated around each equilibria points. Finally, numerical simulations are used to investigate theoretical results. [ABSTRACT FROM AUTHOR]

The actual research paper proposes a model of radio-jamming warfare based on incomplete information dynamic games with known chance, with two actors and competing jamming and anti-jamming strategies. Our model based on the computing of perfect Bayesian equilibrium proof that anti-jamming solutions are more efficient than the classic ones. [ABSTRACT FROM AUTHOR]

Paper presents the theoretical investigation of the structural and vibrational properties of the Li/Cu (110) adsorbed system. The equilibrium atomic configuration, phonon dispersions, and polarization of vibrational modes as well as the local density of phonon states have been calculated on reconstructed and unreconstructed Cu (110) surface. All calculations were performed using the interatomic potentials obtained in terms of the embedded-atom method. The calculated frequencies of localized vibrational modes are in good agreement with existing experimental data. [ABSTRACT FROM AUTHOR]

We study how long-lived, rational, exponentially discounting agents learn in a social network. In every period, each agent observes the past actions of his neighbors, receives a private signal, and chooses an action with the objective of matching the state. Since agents behave strategically, and since their actions depend on higher order beliefs, it is difficult to characterize equilibrium behavior. Nevertheless, we show that regardless of the size and shape of the network, and the patience of the agents, the equilibrium speed of learning is bounded from above by a constant that only depends on the private signal distribution. The full paper is available at https://arxiv.org/abs/2112.14265. [ABSTRACT FROM AUTHOR]

We study robust mechanism design for revenue maximization when selling a single item in an auction, assuming that only the mean of the value distribution and an upper bound on the bidders' valuations for the item are known. Robust mechanism design is a rising alternative to Bayesian mechanism design, which yields designs that do not rely on assumptions like full distributional knowledge, but rather only partial knowledge of the distributions. We seek a mechanism that maximizes revenue over the worst-case distribution compatible with the known parameters. Such a mechanism arises as an equilibrium of a zero-sum game between the seller and an adversary who chooses the distribution, and so can be referred to as the max-min mechanism. Carrasco et al. [2018] derive the max-min pricing when the seller faces a single bidder for the item. We go from max-min pricing to max-min auctions by studying the canonical setting of two i.i.d. bidders, and show the max-min mechanism is the second-price auction with a randomized reserve. We derive a closed-form solution for the distribution over reserve prices, as well as the worst-case value distribution, for which there is simple economic intuition. We also derive a closed-form solution for the max-min reserve price distribution for any number of bidders, and we show that unlike the case of two bidders, a second-price auction with a randomized reserve cannot be an equilibrium for more than two bidders. Our technique for solving the zero-sum game is quite different than that of Carrasco et al. -- we focus on a reduced zero-sum game, where the seller can only choose a distribution for a second-price auction with a randomized reserve price (rather than any mechanism). We then analyze a discretized version of the setting to find conditions an equilibrium would satisfy. By refining the discretization grid, we are able to achieve differential equations, and solving them yields closed-form non-discretized distributions. The resulting distributions for the seller and the adversary are later shown to be an equilibrium for the reduced zero-sum game. For the two-bidder case, we expand our result to an equilibrium of the original zero-sum game, where the seller is not limited to second price auctions with reserve. The full version of the paper is available at https://arxiv.org/abs/2205.09008. [ABSTRACT FROM AUTHOR]

In this work, two models with and without vaccine are constructed. Delay effect is considered for these model. When we are talking about delay on this paper we mean that incubation period. If we have enough vaccine the effect of delay is very tiny. However if there is no vaccine you can see the effect of delay. Two equilibria which are disease free and endemic equilibriums are found and using Lyapunov function, the global stabilities of each equilibria are shown for both models. For the first model it is found that DFE E0 is globally asymtotically stable when R¹0 < 1 and endemic equilibrium E1 is always asymtotically stable. With using similar method E0 is asymptotically stable when R²0 < 1 and E1 is always globally asymptotically stable for model 2. In the last section numerical simulations are given for both models. [ABSTRACT FROM AUTHOR]

This paper is devoted to non-cooperative games in idempotent measures. We consider two kinds of such games. Firstly, players are allowed to play their mixed idempotent strategies. We also consider games where belief of each player about a choice of the strategy by the other players is an idempotent measure. We prove existence of equilibria in both cases and discuss the difference between them. [ABSTRACT FROM AUTHOR]

In this paper, we generalize the existence of Berge's strong equilibrium in Deghdak (see [7]) to discontinuous games in infinite dimensional space of srategy. Moreover, we prove that most of Berge's strong games are essential. [ABSTRACT FROM AUTHOR]

Equilibrium selection in networks is difficult. Players have to both choose their contacts and their actions. In this paper, we formally and experimentally analyze three variants of the game varying the strategy set of the players. We formally show, that limiting the strategy set can both increase and decrease the number of sub game perfect equilibria in the game. Human participants playing these games end up in similar equilibria even though they find it more difficult to reach them, the more equilibria exist. [ABSTRACT FROM PUBLISHER]