This paper considers a 2-stage assembly flowshop scheduling problem where each job is completed by assembling multiple components. The problem has the objective measure of minimizing total completion time. The problem is shown to be NP-complete in the str

The objective of this paper is to evaluate the equilibrium price between PSTN and VoIP telephony services in the case of non-linear utility function. Currently there are two types of wired phone services we are known PSTN (Public Switched Telephone Networ

The objective of this paper is to evaluate the equilibrium price between PSTN and VoIP telephony services in the case of non-linear utility function. Currently there are two types of wired phone service we are known that PSTN (Public Switched Telephone Network) and VoIP (Voice over Internet Protocol). The PSTN telephony which provide high quality service and VoIP which provide relatively low quality service forms a vertically differentiated oligopoly. Therefore, the evaluation of the equilibrium price between PSTN and VoIP services is very important to wired phone service providers. The equilibrium price depends on the state of the service cost function has been proved different value. This paper was evaluated each equilibrium price for the state of the linear cost function and non-linear cost function. Subsequently, analyzed the demand of both services and the equilibrium profit which can maximize the profit of both service providers.