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The analytical model proposed in the paper can be directly applied for modeling and dimensioning of the Iub interface in the UMTS network servicing the mixture of the Release 99 and HSDPA traffic streams. The presented model can be used for the blocking probability and the throughput determination for particular traffic classes carried by the Iub interface. The proposed scheme can be applicable for a cost-effective radio resource management in 3G mobile networks and can be easily applied to network capacity calculations. [ABSTRACT FROM AUTHOR]

Nowadays with the introduction of smart phones along with the development of audio and video applications increase people's demands for the ubiquitous high-data rate coverage. One of the cost-effective solutions adopted in the Long-Term Evolution-Advanced (LTE-Advanced) standard that extends coverage and enhances throughput is the placement of heterogeneous nodes: low-power Relay Nodes (RNs) are deployed to assist transmissions between an evolved Node B (eNB) and multiple User Equipments (UEs). In this framework resource allocation becomes an important and crucial problem that directly influences the potential capacity and coverage improvements. In this paper we overview the concepts of basic relaying and resource allocation in a relay-enhanced LTE-Advanced network. We investigate the performance of an analytical model for a relay-enhanced LTE-Advanced downlink channel, which is presented in detail. Various resource allocation schemes are analyzed, among which, according to the experimental analysis, the proportional one with constraints achieves the best performance. [ABSTRACT FROM AUTHOR]

The paper presents a new simple analytical method for a determination of the blocking probability in a full-availability group carrying a mixture of different multi-rate traffic classes with the compression property. The proposed model can be directly used for modelling of the Iub interface in the UMTS network servicing the Release 99 and HSDPA traffic classes. The described model can be applied for the validation of the efficiency of the Iub interface measured by the blocking probability and the average carried traffic for particular traffic classes. [ABSTRACT FROM AUTHOR]

The paper proposes an analytical approach to blocking probability calculation in the UMTS network. In the proposed method, handoff connections are modelled on the basis of the fixed point methodology. The results of analytical calculation of the blocking probability in the group of cells carrying a mixture of different multi-rate traffic streams are compared with the results of simulation experiments, which confirms a good accuracy of the method. The described calculation scheme is applicable for cost-effective resource management in 3G mobile networks and can be easily applied to network capacity calculations. [ABSTRACT FROM AUTHOR]

This paper proposes a new discrete-time queue analytical model based on BLUE algorithm in order to determine the network congestion in preliminary stages. We compare the original BLUE, which has been implemented in Java, with our proposed analytical model with regards to different performance measures (average queue length, throughput, average queueing delay and packet loss probability). The comparison results show that the proposed discrete-time queue analytical model outperforms BLUE algorithm in terms of throughput and packet loss probability. Moreover, the proposed model maintains the throughput performance regardless whether the amount of the traffic load is light or heavy. Furthermore, we calculate the packet dropping probability function for our analytical model and the BLUE algorithm in order to decide which algorithm drops fewer packets. [ABSTRACT FROM AUTHOR]

An analytical model of the Reno congestion control procedure for Transmission Control Protocol is presented, and its theoretical predictions are compared with real TCP traces and some well-known results [1]. The model is based on Discrete-Time Markov Chain, and it covers slow start, congestion avoidance, fast recovery, fast retransmit, cumulative and selective acknowledgments, timeouts with exponential back-off and appropriate byte counting features of TCP. The model provides a way to estimate Reno TCP performance as a function of round trip time and loss rate for bulk transfer TCP flow. The model allows to compare SACK performance with traditional cumulative acknowledgments. The model can be used to find conditions beneficial for advertised window adjustment to improve performance. [ABSTRACT FROM AUTHOR]

Performance evaluation is an important engineering tool that provides valuable feedback on design choices in the implementation of multi-core systems such as parallel systems, multicomputers, and Systems-on-Chip (SoCs). The significant advantage of analytical models over simulation is that they can be used to obtain performance results for large systems under different configurations and working conditions which may not be feasible to study using simulation on conventional computers due to the excessive computation demands. We present Caspian, a novel analytic performance model, aimed to minimize prediction cost, while providing prediction accuracy. This is accomplished by using a G/G/1 priority queueing model which is used for arbitrary network topology with wormhole routing under arbitrary traffic pattern. The accuracy of this model is examined through extensive simulation results. [ABSTRACT FROM AUTHOR]

According to the flow passage characteristic of rectangular narrow channel and the annular flow predicted analytical model of Critical Heat Flux(CHF) in round tube, the annular flow CHF analytical model in rectangular narrow channel has been gotten. This model can been used to predicted the CHF of boiling two-phase flow annular flow in rectangular narrow channel which the gap width is not less than 0.5mm. Through analysing and calculation, when the inlet width-gap width ratio of rectangular narrow channel is within 25–85, the enhancement of CHF in channel is obvious. Based on the practical and economical sides, this range can be taken as the CHF enhancement reference range of inlet dimensions in rectangular narrow channel. [ABSTRACT FROM AUTHOR]