• Journal of Electrical Engineering and Technology
• /
• v.2 no.4
• /
• pp.543-548
• /
• 2007

We present a dynamic Bayesian network (DBN) model of a generalized class of nonstationary birth-death processes. The model includes birth and death rate parameters that are randomly selected from a known discrete set of values. We present an on-line algorithm to obtain optimal estimates of the parameters. We provide a simulation of real-time characterization of load traffic estimation using our DBN approach.

• Communications for Statistical Applications and Methods
• /
• v.3 no.1
• /
• pp.235-242
• /
• 1996

When the linear growth birth and death process observed at a set of equidistant time points, McNeil and Weiss (1997) present a method for simultaneously estimating the Malthusian parameter and the sum of the two parameters under wery restricted assumptions using a diffusion approximation. This article suggests a method, which does not require the restrictions given by Weiss, for estimating simultaneously the Malthusian parameter and the sum of the two parameters.

• Communications of the Korean Mathematical Society
• /
• v.12 no.1
• /
• pp.177-192
• /
• 1997

The basic theory of the quasi-birth-and-death process is extended to a process which is inhomogeous in levels. Several key results in the standard homogeneous theory hold in a more general context than that usually stated, in particular not requiring positive recurrence. Theser results are subsumed under our development. The treatment is entirely probabilistic.

• Journal of applied mathematics & informatics
• /
• v.29 no.3_4
• /
• pp.803-811
• /
• 2011

We present an algorithmic solution for the stationary distribution of the M/M/c retrial queue in which the retrial times of each customer in orbit are of phase type distribution of order 2. The system is modeled by the level dependent quasi-birth-and-death (LDQBD) process.

• Journal of applied mathematics & informatics
• /
• v.7 no.1
• /
• pp.83-100
• /
• 2000

Many queueing systems such as M/M/s/K retrial queue with impatient customers, MAP/PH/1 retrial queue, retrial queue with two types of customers and MAP/M/$\infty$ queue can be modeled by a level dependent quasi-birth-death(LDQBD) process with linear transition rates of the form ${\lambda}_k$={\alpga}{+}{\beta}k$ at each level $\kappa$. The purpose of this paper is to propose an algorithm to find transient distributions for LDQBD processes with linear transition rates based on the adaptive uniformization technique introduced by van Moorsel and Sanders [11]. We apply the algorithm to some retrial queues and present numerical results.

• Cross-Cultural Studies
• /
• v.39
• /
• pp.127-152
• /
• 2015

This thesis comparatively looks into folklore faiths, expecially child-birth gods related to child-birth customs and aims to find out both nations' faith in child-birth gods and their features. It looks into birth gods protecting delivering mothers and babies by appearing at the delivery sites at time of delivery and child-rearing gods intervening in growth of babies after they are born. In both nations, many gods are believed in for selection of babies, safe delivery and their healthy growth but those appearing at delivery sites are only birth goddesses called Samsinhalmony and Obugami. What make this phenomenon appear in both nations' folklore faiths? Seeing the reason in the fact that common negative concept regarding childbirth exists in both nations' established faiths, the writer comparatively analyzed various cases of delivery-related defilement in both nations' delivery customs. Its result showed that Japan is stronger in delivery-related defilement concept than Korea is. For instance, Japan regard child birth-related defilement more horrible than that related to funeral. Pursuantly, in Japan stricter regulations on childbirth rooms and stricter taboos for babies have been passed down. Besides, in the process of its comparative study on both nations' divine images and appearances, the writer paid attention to the fact that unlike Japan's mountain gods and restroom goddesses appearing at delivery sites, they don't get involved in childbirth in Korea and discussed Japan's theory of reincarnation and its mountain goddess' marginal nature working behind the curtain. I also discussed the phenomenon that both nations' childbirth gods are passed down as Three gods, which means that their faith in childbirth gods has to be seen as a result of the faith in childbirth gods interacting with the faith in Three gods or the Three-gods theory, accordingly I indicated that it is worth re-consideration to see the Three-God Theory as the core of the faith in Samsinhalmoni. Lastly, though in both nations' childbirth faith underlies their fear for divine beings, the faith in childbirth gods, strongly coupled with death heritages, is distributed throughout the nation, which is because Japan's childbirth gods intervening in birth and growth of a new life also actually involve themselves deeply in the sphere of death as well.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.2 no.4
• /
• pp.583-592
• /
• 1998

In this paper, the cell loss rate is analyzed in terms of the input traffic stream of different speed in ATM network. The cell loss rate is calculated by birth-death process of Leaky-Bucket mechanism as the representative algorithm of usage parameter control. The cell loss rate assumed 2-state MMPP input process to be birth-death process by considering the character of token pool about finite capacity queue. The results from numerical analysis show that the cell loss rate decreases abruptly according to the buffer size increase. The computer simulation by SIMSCRIPT II.5 has been done and compared with on/off input source case to verify the analysis results.

• The Transactions of The Korean Institute of Electrical Engineers
• /
• v.58 no.5
• /
• pp.891-897
• /
• 2009

This paper presents a novel load management technique that can lower the peak demand caused by package airconditioner loads in large apartment complex. An intelligent hierarchical load management system composed of a Central Intelligent Management System(CIMS) and multiple Local Intelligent Management Systems(LIMS) is proposed to implement the proposed technique. Once the required amount of the power reduction is set, CIMS issues tokens, which can be used by each LIMS as a right to turn on the airconditioner. CIMS creates and maintains a queue for fair and proper allocation of the tokens among the LIMS requesting tokens. By adjusting the number tokens and queue management policies, desired power reduction can be achieved smoothly. The Markov Birth and Death process and the Balance Equations utilizing the Diffusion Model are employed for evaluation of queue performances during transient periods until the static balances among the states are achieved. The proposed technique is tested using a summer load data of a large apartment complex and give promising results demonstrating the usability in load management while minimizing the customer inconveniences.

• Nuclear Engineering and Technology
• /
• v.53 no.6
• /
• pp.1731-1735
• /
• 2021

The operation of the nuclear reactor requires accurate and fast methods and techniques for analysing its kinetics. These techniques become even more important when the MOX-fuel is used due to the lower value of delayed neutron fraction 𝛽 for ²³⁹Pu. Based on a Birth-and-Death process review, the mathematical model of thermal reactor core has been proposed different from existing ones. The analytical method for thermal point-reactor parameters evaluation is described within this work. The proposed method is applied for analysis of the unsteady transient processes taking place in a thermal reactor at its start-up or shutdown power change, as well as during small accidental power variation from the rated value. Theoretical determination of MASURCA reactor core reactivity through the analysis of experimental data on neutron time spectra was made.

• Journal of applied mathematics & informatics
• /
• v.39 no.5_6
• /
• pp.601-616
• /
• 2021

Retrial queueing models have been studied extensively in the literature. These have many practical applications, especially in service sectors. However, retrial queueing models have their own limitations. Typically, analyzing such models involve level-dependent quasi-birth-and-death processes, and hence some form of a truncation or an approximate method or simulation approach is needed to study in steady-state. Secondly, in general, the customers are not served on a first-come-first-served basis. The latter is the case when a new arrival may find a free server while prior arrivals are waiting in the retrial orbit due to the servers being busy during their arrivals. In this paper, we take a different approach to the study of multi-server retrial queues in which the signals are generated in such a way to provide a reasonably fair treatment to all the customers seeking service. Further, this approach makes the study to be level-independent quasi-birth-and-death process. This approach is different from any considered in the literature. Using matrix-analytic methods we analyze MAP/M/c-type retrial queueing models along with Poisson signals in steady-state. Illustrative numerical examples including a comparison with previously published retrial queues are presented and they show marked improvements in providing a quality of service to the customers.