31,984 research outputs found
Some sensitivity results in stochastic optimal control: A Lagrange multiplier point of view
In this work we provide a first order sensitivity analysis of some
parameterized stochastic optimal control problems. The parameters can be given
by random processes. The main tool is the one-to-one correspondence between the
adjoint states appearing in a weak form of the stochastic Pontryagin principle
and the Lagrange multipliers associated to the state equation
Electron heating and mechanical properties of graphene
The heating of electrons in graphene by laser irradiation, and its effects on
the lattice structure, are studied. Values for the temperature of the electron
system in realistic situations are obtained. For sufficiently high electron
temperatures, the occupancy of the states in the band of graphene is
modified. The strength of the carbon-carbon bonds changes, leading to the
emergence of strains, and to buckling in suspended samples. While most
applications of `strain engineering' in two dimensional materials focus on the
effects of strains on electronic properties, the effect studied here leads to
alterations of the structure induced by light. This novel optomechanical
coupling can induce deflections in the order of nm in micron size
samples
A Semi-Lagrangian scheme for a degenerate second order Mean Field Game system
In this paper we study a fully discrete Semi-Lagrangian approximation of a
second order Mean Field Game system, which can be degenerate. We prove that the
resulting scheme is well posed and, if the state dimension is equals to one, we
prove a convergence result. Some numerical simulations are provided, evidencing
the convergence of the approximation and also the difference between the
numerical results for the degenerate and non-degenerate cases.Comment: 21 pages, 8 figure
Future entrepreneurâs profile
Given that entrepreneurship plays a key role in the development of a countryâs economy, governments should stimulate entrepreneurial orientation, particularly among youngsters in their formative years; schools must play a pertinent role in the promotion and support of these capacities. Indeed, the European Commission advises that schools foster such skills.
In this context, we apply a frame to screen school populations in the Azores Islands, Portugal, for prospects of entrepreneurship and to study the profiles of those who noticeably show entrepreneurial orientations.
Knowing the ideal combination of personality traits that foretell young entrepreneurs, schools can develop the syllabuses that are best aimed at promoting entrepreneurship and increasing the capacities of those who prove to be entrepreneurially oriented.
This work leads to the following main findings: first, that one quarter of all senior students in high school in the Azores Islands bears prospects for entrepreneurship and, second, this same group shows a well-defined psychological profile that may vary depending on oneâs willingness to expend effort.info:eu-repo/semantics/publishedVersio
Incorporating waiting time in competitive location models: Formulations and heuristics
In this paper we propose a metaheuristic to solve a new version of the Maximum Capture Problem. In the original MCP, market capture is obtained by lower traveling distances or lower traveling time, in this new version not only the traveling time but also the waiting time will affect the market share. This problem is hard to solve using standard optimization techniques. Metaheuristics are shown to offer accurate results within acceptable computing times.Market capture, queuing, ant colony optimization
Locating emergency services with priority rules: The priority queuing covering location problem
One of the assumptions of the Capacitated Facility Location Problem (CFLP) is that demand is known and fixed. Most often, this is not the case when managers take some strategic decisions such as locating facilities and assigning demand points to those facilities. In this paper we consider demand as stochastic and we model each of the facilities as an independent queue. Stochastic models of manufacturing systems and deterministic location models are put together in order to obtain a formula for the backlogging probability at a potential facility location. Several solution techniques have been proposed to solve the CFLP. One of the most recently proposed heuristics, a Reactive Greedy Adaptive Search Procedure, is implemented in order to solve the model formulated. We present some computational experiments in order to evaluate the heuristicsâ performance and to illustrate the use of this new formulation for the CFLP. The paper finishes with a simple simulation exercise.Location, queuing, greedy heuristics, simulation
Prediction of entrepreneurship : an ordered regression approach
Entrepreneurship is a popular research topic over the last several decades. Various authors study the characteristics that best define future entrepreneur profiles. In this paper, we apply a framework to screen school populations in the Azores Islands, Portugal, for prospects of entrepreneurship and to study the profiles of those who show noticeably entrepreneurial orientations. The contribution of the paper consists of applying ordered regression to explain the entrepreneurial prospects of students in high school.N/
- âŠ