610 research outputs found
The GUP effect on tunnelling of massive vector bosons from the 2+1 dimensional black hole
In this study, the Generalized Uncertainty Principle (GUP) effect on the
Hawking radiation formed by tunneling of a massive vector boson particle from
the dimensional New-type Black Hole was investigated. We used modified
massive vector boson equation based on the GUP. Then, the Hamilton-Jacobi
quantum tunneling approach was used to work out the tunneling probability of
the massive vector boson particle and, Hawking temperature of the black hole.
Due to the GUP effect, the modified Hawking temperature was found to depend on
the black hole properties, the AdS radius, and on the energy, mass and
total angular momentum of the tunneling massive vector boson. In the light of
these results, we also observed that modified Hawking temperature increases by
the total angular momentum the particle while it decreases by the energy and
mass of the particle, and the graviton mass. Also, in the context of the GUP,
we see that the Hawking temperature due to the tunnelling massive vector boson
is completely different from both that of the spin-0 scalar and the spin-1/2
Dirac particles obtained in the previous study. We also calculate the heat
capacity of the black hole using the modified Hawking temperature and then
discuss influence of the GUP on the stability of the black hole.Comment: 11 pages, accepted for publication for Advances in High Energy
Physic
The GUP effect on Hawking Radiation of the 2+1 dimensional Black Hole
We investigate the Generalized Uncertainty Principle (GUP) effect on the
Hawking radiation of the 2+1 dimensional Martinez-Zanelli black hole by using
the Hamilton-Jacobi method. In this connection, we discuss the tunnelling
probabilities and Hawking temperature of the spin-1/2 and spin-0 particles for
the black hole. Therefore, we use the modified Klein-Gordon and Dirac equations
based on the GUP. Then, we observe that the Hawking temperature of the scalar
and Dirac particles depend on not only the black hole properties, but also the
properties of the tunnelling particle, such as angular momentum, energy and
mass. And, in this situation, we see that the tunnellig probability and the
Hawking radiation of the Dirac particle is different from that of the scalar
particle.Comment: 9 page
Quantum Gravity Effect on the Tunneling Particles from 2+1 dimensional New-type Black Hole
We investigate the Generalized Uncertainty Principle (GUP) effect on the
Hawking temperature for the 2+1 dimensional New-type black hole by using the
quantum tunneling method for both the spin-1/2 Dirac and the spin-0 scalar
particles. In computation of the GUP correction for the Hawking temperature of
the black hole, we modified Dirac and Klein-Gordon equations. We observed that
the modified Hawking temperature of the black hole depends not only on the
black hole properties, but also on the graviton mass and the intrinsic
properties of the tunneling particle, such as total angular momentum, energy
and mass. Also, we see that the Hawking temperature was found to be probed by
these particles in different manners. The modified Hawking temperature for the
scalar particle seems to be lower compared to its standard Hawking temperature.
Also, we find that the modified Hawking temperature of the black hole caused by
Dirac particle's tunnelling rised by the total angular momentum of the
particle. It is diminishable by the energy and mass of the particle and
graviton mass as well. These intrinsic properties of the particle, except total
angular momentum for the Dirac particle, and graviton mass may cause screening
for the black hole radiation.Comment: 11 page
Solving crew scheduling problem in offshore supply vessels, heuristics and decomposition methods
For the efficient utilisation of resources in various transportation settings, scheduling is a significant area of research. Having crew as the main resource for operation maintenance, scheduling crew have been a powerful decision making tool for optimisation studies. This research provides a detailed real case study analysis regarding the difficulties in planning crew in maritime industry. As a special case study, this thesis researches crew scheduling in offshore supply vessels which are used for specific operations of a global scaled company in oil and gas industry deeply with modified formulations, heuristics and decomposition methods.An extended version of computational study for a simple formulation approach (Task Based Model) is applied as deeper analysis to Leggate (2016). Afterwards, more realistic approach to the same problem is revised. Following the revision, a customized and thorough computational study on the heuristic method with various settings is designed and implemented in C++. After elaborated analysis completed on the suggested models firstly, a modification on Time Windows model is presented to increase the efficacy. This modification provides a sharp decrease in upper bounds within a short time compared to the previously suggested models. Through this suggestion, more economic schedules within a short period of time are generated.Achieving high performances from the modified model, an application of a decomposition algorithm is provided. We implemented a hybrid solution of Benders Decomposition with a customized heuristic for the modified model. Although this hybrid solution does not provide high quality solutions, it evaluates the performance of possible decomposed models with potential improvements for future research. An introduction to robust crew scheduling in maritime context is also given with a description of resources of uncertainty in this concept and initial robust formulations are suggested.For the efficient utilisation of resources in various transportation settings, scheduling is a significant area of research. Having crew as the main resource for operation maintenance, scheduling crew have been a powerful decision making tool for optimisation studies. This research provides a detailed real case study analysis regarding the difficulties in planning crew in maritime industry. As a special case study, this thesis researches crew scheduling in offshore supply vessels which are used for specific operations of a global scaled company in oil and gas industry deeply with modified formulations, heuristics and decomposition methods.An extended version of computational study for a simple formulation approach (Task Based Model) is applied as deeper analysis to Leggate (2016). Afterwards, more realistic approach to the same problem is revised. Following the revision, a customized and thorough computational study on the heuristic method with various settings is designed and implemented in C++. After elaborated analysis completed on the suggested models firstly, a modification on Time Windows model is presented to increase the efficacy. This modification provides a sharp decrease in upper bounds within a short time compared to the previously suggested models. Through this suggestion, more economic schedules within a short period of time are generated.Achieving high performances from the modified model, an application of a decomposition algorithm is provided. We implemented a hybrid solution of Benders Decomposition with a customized heuristic for the modified model. Although this hybrid solution does not provide high quality solutions, it evaluates the performance of possible decomposed models with potential improvements for future research. An introduction to robust crew scheduling in maritime context is also given with a description of resources of uncertainty in this concept and initial robust formulations are suggested
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