When there is an outlier in the data set, the efficiency of traditional methods decreases. In order to solve this problem, Kadilar et al. (2007) adapted Huber-M method which is only one of robust r...

Modified ratio estimators using robust regression methods

http://scientiairanica.sharif.edu/article_22000_8a64f83468d426cda568abde2acab4bc.pdf

Quantile regression-ratio-type estimators for mean estimation under complete and partial auxiliary information

This paper suggests a new family of exponential estimators in the two-phase sampling using the information of an auxiliary attribute. Theoretically, we obtain the mean square error (MSE) for these ...

New class of exponential estimators for finite population mean in two-phase sampling

Efficient cooperative access class barring with load balancing and traffic adaptive radio resource management for M2M communications over LTE-A

In this article, we propose a family of exponential ratio estimators for the estimation of the population mean of the study variable using the information of the population proportion posse...

Novel family of exponential estimators using information of auxiliary attribute

The control of traffic intensity is one of the important problems in the study of queueing systems. Rao et al. (1984) developed a method to detect changes in the traffic intensity in queueing systems of the and types based on the Sequential Probability Ratio Test (SPRT). In this paper, SPRT is theoretically investigated for two different phase-type queueing systems which consist of hyperexponential and mixed Erlang. Also, for testing against , Operating Characteristic (OC) and Average Sample Number (ASN) functions are obtained with numerical methods using multipoint derivative equations according to different situations of and type errors. Afterward, numerical illustrations for each model are provided with Matlab programming.

https://downloads.hindawi.com/journals/mpe/2013/241241.pdf

Control of Traffic Intensity in Hyperexponential and Mixed Erlang Queueing Systems with a Method Based on SPRT

In this study, the use of taylor series method in the calculation of some means with single auxiliary variable developed in a simple random sampling and mean square error unit ratio estimators having certain properties was investigated. An application was performed in respect thereof. The study population (mass) included 111 secondary schools from 18 districts of Trabzon province. Auxiliary variable (x) was taken as the number of students whereas the main variable (y) was taken as the number of teachers. Sample size was calculated as 45 for unit ratio that has certain features. Afterwards, theoretically proposed mean and units ratio estimators having certain properties were compared numerically. Random sampling was performed using the SPSS 20 program thus giving an equal chance to the units sampled and variability in the population was protected.

/pdf/investigation-of-some-estimators-via-taylor-series-approach-2lxr3l7dt6.pdf

Investigation of Some Estimators Via Taylor Series Approach and an Application

We consider a new queuing model with sequential two stations (stages), single server at each station, where no queue is allowed at station 2 and with no restriction at station 1. There is a FCFS service discipline in which the input stream is Poisson having rate . The service time of any customer at server () is exponential with parameter . The state probabilities and loss probability of this model are given. The performance measures are obtained and optimized, and, additionally, the model is simulated. The simulation results, exact results, and optimal results of the performance measures are numerically computed for different parameters.

/pdf/a-two-stage-model-queueing-with-no-waiting-line-between-280w4hj3m7.pdf

A Two-Stage Model Queueing with No Waiting Line between Channels

A stochastic model consisting of two heterogeneous channels and having no waiting room in front of each is considered. A customer who has completed his service in channel 1 while channel 2 is busy blocks channel 1 with probability or leaves the system with probability. This model was analysed: expected number of customer and loss probability of customer are calculated and optimal ordering of channels minimizing parameters has been found. Additionally, this model was simulated; furthermore, simulated and exact results of loss probabilities of customers were given in the tables.

https://downloads.hindawi.com/journals/mpe/2013/529010.pdf

The Simulation and Minimization of Loss Probability in the Tandem Queueing with Two Heterogeneous Channels

The aim of this paper is to analyze a tandem queueing model with two stages. The arrivals to the first stage are Poisson stream and the service time at this stage is exponential. There is no waiting room at first stage. The service time is hyperexponential and no waiting is allowed at second stage. The transition probabilities and loss probabilities of this model are obtained. In addition, the loss probability at second stage is optimized. Performance measures and the variance of the numbers of customers of this tandem queueing model are found. It is seen that the numbers of customers in first stage and second stage are dependent. Finally we have simulated this queueing model. For different values of parameters, exact values, simulated values, and optimal values of obtained performance measures of this model are numerically shown in tables and graphs.

/pdf/the-analysis-optimization-and-simulation-of-a-two-stage-7rdj351ye9.pdf

Müjgan Zobu

Papers

Control of Traffic Intensity in Hyperexponential and Mixed Erlang Queueing Systems with a Method Based on SPRT

Investigation of Some Estimators Via Taylor Series Approach and an Application

A Two-Stage Model Queueing with No Waiting Line between Channels

The Simulation and Minimization of Loss Probability in the Tandem Queueing with Two Heterogeneous Channels

The Analysis, Optimization, and Simulation of a Two-Stage Tandem Queueing Model with Hyperexponential Service Time at Second Stage