Search

This paper analyses single server correlated batch arrival and correlated batch service queue with innumerable waiting space in discrete-time. The arrival and service processes are governed by discrete batch Markovian arrival process and discrete Markovian service process with general bulk service rule, respectively. Observing two consecutive random epochs, we construct general structure transition probability matrix and it is then reblocked to the desired M/G/1 structure. The UL-type RG-factorization approach combined with spectral expansion method is adopted to unravel the queue length distribution at random epoch. The relationships are undertaken to obtain the queue length distributions at pre-arrival, outside observer's, intermediate and post-departure epochs. Our most challenging effort is to derive the probability mass functions of waiting time and service batch size for arbitrary customer in an arriving batch. We address the warehouse management process for finished products from dealer to retailer as a potential practical use of our batch queue with correlation in both arrival and service, and provide the effect of our queueing behaviour in this application based on our analytical and computational investigation. Based on the implementation of parametrized numeric experiments with numerous categories, we impart our computational results to validate the analytical findings reported in this investigation. [ABSTRACT FROM AUTHOR]

This paper investigates an infinite buffer fluid queueing model driven by a state-dependent birth-death process prone to catastrophes. We use the Laplace-Stieltjes transform and continued fraction approaches to establish precise expression for the joint probability of the content of the buffer and the number of customers in an M/M/1 queueing model. The importance of the proposed system is that, in numerous practical situation, the service facility has defence mechanisms in place to deal with long waits. Under the strain of a significant backlog of work, the servers may improve their service rate. Therefore, considering the state-dependent character of queueing systems is of relevance. For example, congestion control technologies prevent long queues forming in computer and communication systems by adjusting packet transmission speeds based on the length of the queue (of packets) at the source or destination. Theoretical results are supported by numerical illustrations. [ABSTRACT FROM AUTHOR]

The adsorption of N2 at -195.846 °C on the bentonite samples has been studied to see a fit for Freundlich, Langmuir, Temkin, and BET isotherms. BET and BJH surface area of pores have been determined. The average pore diameter has been found to be 5.8152 nm indicating the mesopores of the bentonite powder. Isotherm plots of relative pressure (...) vs quantity adsorbed (cm³/g STP) shows adsorption and desorption. Freundlich plot, Temkin plot, and BET isotherm plot have been utilized to explain the adsorption and desorption behavior of N2 on mesoporous bentonite. BET surface areas for samples XDSB1, XDSB2, XDSB3 and XDSB4 are 157.7719 m²/g, 39.0354 m²/g, 54.2687 m²/g, and 87.4881 m²/g respectively. BJH adsorption surface area of pores is 146.5264 m²/g for XDSB1, 23.8361 m²/g for XDSB2, 54.2687 m²/g for XDSB3 and 57.0980 m²/g for XDSB4. A comparison of the surface areas shows that XDSB1 has the highest surface area and XDSB2 has the lowest surface area. Adsorption pore diameter (...) by BET and BJH adsorption average pore diameter (...) for XDSB1 are 58.152 Å and 61.810 Å respectively indicating mesopores in bentonite powder. The BET isotherm plot of ... vs ... shows type II of BET i.e. large deviation from the Langmuir model. The nature of the graph explains the formation of additional layers of physically adsorbed gas molecules. [ABSTRACT FROM AUTHOR]

In this paper, some Edelstein's fixed point theorems involving the concept of asymptotic centre in uniformly convex Banach spaces are proved in Bag and Samanta type fuzzy normed linear spaces. [ABSTRACT FROM AUTHOR]

The manuscript deals with the utilization of Neutron Activation Analysis (NAA), external (in air) Particle Induced Gamma-ray Emission (PIGE) and X-Ray Fluorescence (XRF) for comprehensive characterization of Indian coal in order to evaluate their quality in terms of ash contents. NAA was used involving short irradiation at Pneumatic Carrier Facility (PCF) at Dhruva reactor, India, for determination of Na, Mg, Al and K; whereas long irradiation at Apsara-U reactor was used for estimation of Fe and Ca. External PIGE was applied for quantification of low Z elements (Na, Mg, Al and Si). Method was validated using coal-based standard reference materials: NIST 1635a and 1633c. Comparative evaluation was also carried out using Energy Dispersive X-Ray Fluorescence (EDXRF) spectroscopy. Total concentration of Na, Mg, Al, Si, K, Ca, Ti and Fe oxides has been used as markers for identifying the quality of coal in terms of coal ash contents. Elements such as Sc, Cr, Co, Zn, Se, Cs, Ce, Sm, Hf, U and Th were determined at trace level using conventional NAA techniques after long irradiation at Apsara-U reactor. The coal with higher ash content was found to contain high concentration of trace elements and the better quality coal contains lower concentration of trace elements. [ABSTRACT FROM AUTHOR]