This paper analyzes a discrete-time $Geo/Geo/c$ queueing system with multiple working vacations and reneging in which customers arrive according to a geometric process. As soon as the system gets empty, the servers go to a working vacations all together. The service times during regular busy period, working vacation period and vacation times are assumed to be geometrically distributed. Customer...

Ant Colony Optimization (ACO) algorithms are basically developed for discrete optimization and hence their application to continuous optimization problems require the transformation of a continuous search space to a discrete one by discretization of the continuous decision variables. Thus, the allowable continuous range of decision variables is usually discretized into a discrete set of allowab...

background: several reservoir systems have been constructed for hydropower generation around the world. hydropower offers an economical source of electricity with reduce carbon emissions. therefore, it is such a clean and renewable source of energy. reservoirs that generate hydropower are typically operated with the goal of maximizing energy revenue. yet, reservoir systems are inefficiently ope...

of Licentiate Thesis Author Maria Pittou Title of Thesis Contributions to multi-view modeling and the multi-view consistency problem for infinitary languages and discrete systems

Image fusion combines information from multiple images of the same scene to get a composite image that is more suitable for human visual perception or further image-processing tasks. In this paper the multi source medical images like MRI (Magnetic Resonance Imaging), CT (computed tomography) & PET (positron emission tomography) are fused using different multi scale transforms. We compare variou...

banking and financial services are important parts of the service industry. quality of service in the banking industry has a close relationship with customer satisfaction service system. banks could create competitive advantage by increasing customer satisfaction and reduce costs in today's competitive environment. this paper presents a decision-making model to obtain optimum tasks assigne...

One main group of a transportation network is a discrete hub covering problem that seeks to minimize the total transportation cost. This paper presents a multi-product and multi-mode hub covering model, in which the transportation time depends on travelling mode between each pair of hubs. Indeed, the nature of products is considered different and hub capacity constraint is also applied. Due to ...

Abstract: Numerical solution techniques for a class of hybrid (discrete event / continuous variable) optimal control problems (HOCP) are described, and their potential use in robotic applications is demonstrated. HOCPs are inherently combinatorial due to their discrete event aspect which is one of the main challenges when numerically solving for optimal hybrid trajectories. One may associate a ...

optimal reactive power dispatch (orpd) is a multi-variable problem with nonlinear constraints and continuous/discrete decision variables. due to the stochastic behavior of loads, the orpd requires a probabilistic mathematical model. in this paper, monte carlo simulation (mcs) is used for modeling of load uncertainties in the orpd problem. the problem is formulated as a nonlinear constrained mul...

for multi-objective optimal reactive power dispatch (morpd), a new approach is proposed where simultaneous minimization of the active power transmission loss, the bus voltage deviation and the voltage stability index of a power system are achieved. optimal settings of continuous and discrete control variables (e.g. generator voltages, tap positions of tap changing transformers and the number of...