جستجوی مقالات مرتبط با کلیدواژه "queue theory" در نشریات گروه "فنی و مهندسی"

Mobile Edge computing is a new paradigm that allows users to combat the constraints of mobile devices For overcoming the long delay of cloud computing which decreases the quality of service, the users send their data to the server which is located at the edge of the network instead of sending a part of the program to a cloud server which is located in place far from the users. In this paper, a system which consists of a cell and several users is considered in which the network users to accomplish their computations request service from cloud and edge servers that are participating with each other. It is assumed that the users access the radio spectrum by a Non-orthogonal Multiple Access (NOMA) method and the queue theory is used for modeling the problem from the users and server sides. The main goal is to minimize the total users' energy consumption, the delay in users' receiving service, and the whole cost of using servers. The mathematical model of this problem would result in a multi-objective constraint non-convex optimization problem. SCA method is used to achieve the globally optimum solution. Through the simulation results, it is shown that by the applied assumptions in the proposed model, the amount of energy, delay and total cost of network is decreased around 50%.

The main purpose of this paper is to investigate the effect of capacity on queue parameters, in order to improve the efficiency of the road by creating a proper change in the capacity of the highway and reducing the delay caused by queuing. As a system sends a parameter out of the output at a specified time interval, in other words, the system does not have the ability to service the entire input request, the queue is created and the vehicles must wait for service. In traffic queues, in addition to reducing the quality of the trip, Undesirable effect on traffic flow safety is also pronounced. The demand for the use of the road is variable throughout the day, and unfortunately there is no possibility of storing supplies in transportation. Consequently, in many periods of time, it is not possible to use capacity. It is possible to reduce the delay in the roadway by changing the capacity at different intervals. This involves sensitivity analysis on the effect of the capacity on the delay parameters. In this study, a definite queuing model is presented that can estimate the effect of changes in freeway bottleneck capacity on user delays. The formulation of the general problem is based on the definite queue theory and is solved by numerical analysis. A sample problem is investigated using a computer program. Finally, a sensitive analysis has been made on capacity changes. The results indicate that queue performance indicators improve with increasing capacity. By analyzing each case and performing such a sensitive analysis along with applying a suitable policy that changes the capacity of the way, the delay can be reduced and the route efficiency improved. Moreover, the proposed method helps to improve understanding the failure phenomenon in the upstream of traffic jams and large queuing models, and the sensitive analysis can be used to control traffic management. Using the proposed numerical method for each log entry and exit rate, one can calculate queuing parameters in each system (even non-traffic) and calculate the appropriate capacity with expected latency parameters.