The Tragedy of the Anti-Commons: A New Problem. An Application to the Fisheries.

The operation and management of common property resources (“the commons”) have been exhaustively examined in economics and political science, both in formal analysis and in practical applications. “Tragedy of the Commons” metaphor helps to explain why people overuse shared resources. On the other side, Anti-Commons Theory is a recent theory presented by scientists to explain several situations about new Property Rights concerns. An “anti-commons” problem arises when there are multiple rights to exclude. Little attention has been given to the setting where more than one person is assigned with exclusion rights, which may be exercised. We analyze the “anti-commons” problem in which resources are inefficiently underutilized rather than over-utilized as in the familiar commons setting. In fact, these two problems are symmetrical in several aspects.Anti-Commons Theory; Property Rights

Addressing reserves and pension funds through gambler’s ruin and generalized Brownian motion process

We used the random walk to model the problem of reserves. The classic case of a stochastic process is the example of random walks, which are used to study a set of phenomena and, particularly, as in this article, to study models of reserves evolution. Random walks also allow the construction of significant complex systems and are used as an instrument of analysis, being used in this study for giving a theoretical characteristic to specific types of systems. Our goal is mainly to study reserves to see how to ensure that pension funds are sustainable. This paper, by covering a classic approach to the study of pension funds, makes possible to draw interesting conclusions about the problem of reserves. We also consider the Brownian motion to model the pensions fund assets and liability management politics. In this context, it was possible to obtain expressions for the expected value of the pensions fund perpetual maintenance cost present value, also for the expected value of the maintenance cost up to time t, indicators of a fund maintenance policy expenditures.info:eu-repo/semantics/acceptedVersio

Diffusion and Brownian motion processes in modeling the costs of supporting non-autonomous pension funds

In this chapter, we consider pensions funds not sufficiently auto financed and systematically maintained with an outside financing effort, usually non-autonomous pension’s funds. This financial effort, made by the managing entity, translates as capital injections into the fund. The objective of this work is to develop a tool that allows predicting the appropriate moments to carry out these interventions and the respective amounts. So, we propose to represent the unrestricted reserves value process of this kind of funds, through a time homogeneous diffusion process with finite expected time till the ruin. A financial tool that regenerates the diffusion is also admitted, at some level with positive value every time it hits a barrier at the origin. Then the financing effort may be modeled as a renewal-reward process if the regeneration level is kept constant. The perpetual maintenance cost expected values evaluation and of the finite time maintenance cost are studied. Then, we focus on a particular situation of this approach, arising when the unrestricted reserves value process behaves as a generalized Brownian motion process.info:eu-repo/semantics/acceptedVersio

Gambler’s ruin random walks and Brownian motions in reserves modelling: Application to pensions funds sustainability

We used the random walk to model the problem of reserves. The classic case of a stochastic process is the example of random walks, which are used to study a set of phenomena and, particularly, as in this article, models of reserves evolution. Random walks also allow the construction of significant complex systems and are also used as an instrument of analysis, being used in the sense of giving a theoretical characteristic to other types of systems. Our goal is primarily to study reserves to see how to ensure that pension funds are sustainable. This classic approach to the study of pension funds makes possible to draw interesting conclusions about the problem of reserves.info:eu-repo/semantics/acceptedVersio

Infinite servers queue systems busy period - a practical case on logistics problems solving

In this paper it is exemplified how the busy period of an infinite servers queue is applied to the equipments failures management. With this model it is possible to obtain system performance measures and also to contribute to solve organizing structures’ problems, by minimizing the risks of the organizations inoperative structures, with considerable logistics pernicious consequences for companies and often also for the regions where the companies are insertedinfo:eu-repo/semantics/publishedVersio

On a Scalable Path for Multimode SDM Transmission

We investigate transceiver design and digital signal processing for spatially multiplexed transmission over multimode fibers. In conventional architectures, the full spatial domain of the transmission fiber has to be detected and processed such that the modal walk-off and mixture can be estimated and equalized. These architectures scale poorly with the number of modes supported, besides the sparsity of the fiber transfer matrix is not fully exploited. Instead, here we aim to employ selective mode vector launch and detection in order to minimize the number of optical front-ends required. In this case, an ideal basis for multiplexing is offered by principal modes, that to first order are frequency independent. We show that such mode vector basis can be used for full baud rate transmission over inter-data center distances despite limited coherence bandwidth and vulnerability to environmental-induced drift of the optical channel. It is shown that crosstalk at the receiver front-end can be significantly suppressed, critically reducing the number of coherent receiver front-ends to that of spatial tributaries aimed for data transmission - as opposed to the total number of fiber modes. Residual crosstalk can still be experienced due to environmental-induced channel drift and loss of orthogonality in presence of mode dependent loss. Multiple-input single-output digital signal processing is shown to be effective in this case, with the required equalizer array size scaling sub-linearly with the number of tributaries. A multimode fiber with 156 spatial and polarization modes and optimized for low modal dispersion is considered

In the search for the infinite servers queue with Poisson arrivals busy period distribution exponential behaviour

This paper purpose is to investigate exponential behavior conditions for the M'G'oo; queue busy period length distribution. It is presented a general theoretical result that is the basis of this work. The complementary analysis rely on the M'G'oo; queue busy period length distribution moments computation. In M'G'oo; queue practical applications - in economic, management and business areas - the management of the effective number of servers is essential since the physical presence of infinite servers is not viable and so it is necessary to create that condition through an adequate management of the number of servers during the busy period.info:eu-repo/semantics/acceptedVersio

A queue model to monitor the conversion from ICEV to EV, HEV and DV in a scarce oil environment

Grounded on the M|G|∞ queue system, we build a model to analyze a situation in which ICEV-Internal Combustion Engine Vehicles, moved only by the action of an internal combustion engine, get idle, in a scarce conventional energy ambience, and are either recycled, turning either EV-Electric Vehicles or HEV-Hybrid Electric Vehicles, or dismantled becoming DV-Dismantled Vehicles. We model the three situations: EV, HEV and DV with the same purpose. The model allows concluding that when the rhythm ICEV become EV, HEV and DV is greater than the rate at which they become idle the system has a tendency to balance. In addition, we perform a cost-benefit analysis.info:eu-repo/semantics/acceptedVersio

Chaos in social and political phenomena: the drop of honey effect

Chaos theory has been first applied to natural sciences and then to the humanities and social sciences and, since the beginning, got rapidly a developing field. Chaos is extremely complex and difficult to be identified in the real world. Even using the workable information, it is possible, anyway, up to a certain extent, to find specific mathematical relationships for problems to be solved. In this study some issues are presented in order to work this subject in the humanities and social sciences.info:eu-repo/semantics/publishedVersio

Solving logistics’ problems through an infinite servers queue systems approach

It is exemplified in this article a proceeding based on the busy period concept of infinite servers queues systems to deal with equipment’s failures. Evidently, the occurrence of failures in the equipment is a situation that demands managerial procedures in order to repair the failures as quick as possible and also to minimize the losses in the equipment operation. The model presented here - by means of infinite servers queuing systems - allows to generate system performance measures. It also contributes to solve organizational structures’ problems, by minimizing the risks of the inoperative structures of organizations, which have considerable logistics pernicious consequences for companies and often for regions where they are implanted.info:eu-repo/semantics/acceptedVersio