Absorbing Markov Chain Research Papers (original) (raw)
This paper is an attempt to develop a generic simulation‐based approach to assess transit service reliability, taking into account interaction between network performance and passengers' route choice behaviour. Three types of... more
This paper is an attempt to develop a generic simulation‐based approach to assess transit service reliability, taking into account interaction between network performance and passengers' route choice behaviour. Three types of reliability, say, system wide travel time reliability, schedule reliability and direct boarding waiting‐time reliability are defined from perspectives of the community or transit administration, the operator and passengers. A Monte Carlo simulation approach with a stochastic user equilibrium transit assignment model embedded is proposed to quantify these three reliability measures of transit service. A simple transit network with a bus rapid transit (BRT) corridor is analysed as a case study where the impacts of BRT components on transit service reliability are evaluated preliminarily.
This paper is an attempt to develop a generic simulation‐based approach to assess transit service reliability, taking into account interaction between network performance and passengers' route choice behaviour. Three types of... more
This paper is an attempt to develop a generic simulation‐based approach to assess transit service reliability, taking into account interaction between network performance and passengers' route choice behaviour. Three types of reliability, say, system wide travel time reliability, schedule reliability and direct boarding waiting‐time reliability are defined from perspectives of the community or transit administration, the operator and passengers. A Monte Carlo simulation approach with a stochastic user equilibrium transit assignment model embedded is proposed to quantify these three reliability measures of transit service. A simple transit network with a bus rapid transit (BRT) corridor is analysed as a case study where the impacts of BRT components on transit service reliability are evaluated preliminarily.
A practical dynamical model of an efficient Simple Genetic Algorithm is presented, introducing in the matrix of the Nix and Vose Markov model a practical postulate related to the schema theorem, that induces deterministic correction... more
A practical dynamical model of an efficient Simple Genetic Algorithm is presented, introducing in the matrix of the Nix and Vose Markov model a practical postulate related to the schema theorem, that induces deterministic correction factors in the matrix, through Heaviside´s unitary step function. This alteration permits SGA to evolve by efficient deterministic channels. The model simulates the real behaviour of an efficient SGA. The Markov chain is transformed into an absorbing Markov chain. Using the absorbing theory, the expected waiting time, EWT, is computed easily in any situation. For the case of maximum uncertainty, it is obtained an expression for EWT that improves from the standard Nix and Vose model, in relation to the experimental data. Through the deterministic paths, the steady state is obtained when the absorbing state, global optimum, is reached. To emphasize that, with this practical improvement, the theoretical unification of the model of Nix and Vose for the SGA w...
- by Gabriel Winter
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This letter is concerned with the distributed localization issue for wireless sensor networks subject to deception attacks. It is assumed that malicious nodes randomly launch attacks to tamper the ranging information between sensors. In... more
This letter is concerned with the distributed localization issue for wireless sensor networks subject to deception attacks. It is assumed that malicious nodes randomly launch attacks to tamper the ranging information between sensors. In order to accommodate the effects of deception attacks, a trust assessment-based distributed localization algorithm is proposed. Combined with data fusion of barycentric coordinates, our algorithm can achieve accurate localization. Finally, numerical simulations are given to validate the effectiveness of the proposed localization algorithm.
Swarms of robots have several military and civilian applications such as search and rescue missions, terrain exploration, industrial control, public security, fire combat, and several others. One of the biggest challenges of cooperative... more
Swarms of robots have several military and civilian applications such as search and rescue missions, terrain exploration, industrial control, public security, fire combat, and several others. One of the biggest challenges of cooperative swarming in such application domains is the real-time coordination of the robot's movements in a wide-area setting, where it is expensive, or even impossible, to set up a dedicated radio communication infra-structure for the robot control. Hence, one has to resort to wide-area wireless networks. This, however, implies in a higher communication latency, which may have a significant impact on the coordination synchronicity of the swarm. In this work we tackle the swarm formation problem in wide-area settings, and propose a bandwith-efficient multi-robot coordination protocol that uses cellular 2G/3G/4G networks. This protocol has the notion of a swarm leader and is implemented on the top of an in-house developed mobile middleware with group-cast co...
The advancement in computing and telecommunication has broadened the applications of drones beyond military surveillance to other fields, such as agriculture. Livestock farming using unmanned aerial vehicle (UAV) systems requires... more
The advancement in computing and telecommunication has broadened the applications of drones beyond military surveillance to other fields, such as agriculture. Livestock farming using unmanned aerial vehicle (UAV) systems requires surveillance and monitoring of animals on relatively large farmland. A reliable communication system between UAVs and the ground control station (GCS) is necessary to achieve this. This paper describes learning-based communication strategies and techniques that enable interaction and data exchange between UAVs and a GCS. We propose a deep auto-encoder UAV design framework for end-to-end communications. Simulation results show that the auto-encoder learns joint transmitter (UAV) and receiver (GCS) mapping functions for various communication strategies, such as QPSK, 8PSK, 16PSK and 16QAM, without prior knowledge.
American universities use a procedure based on a rolling six-year graduation rate to calculate statistics regarding their students’ final educational outcomes (graduating or not graduating). As an alternative to the six-year graduation... more
American universities use a procedure based on a rolling six-year graduation rate to calculate statistics regarding their students’ final educational outcomes (graduating or not graduating). As an alternative to the six-year graduation rate method, many studies have applied absorbing Markov chains for estimating graduation rates. In both cases, a frequentist approach is used. For the standard six-year graduation rate method, the frequentist approach corresponds to counting the number of students who finished their program within six years and dividing by the number of students who entered that year. In the case of absorbing Markov chains, the frequentist approach is used to compute the underlying transition matrix, which is then used to estimate the graduation rate. In this paper, we apply a sensitivity analysis to compare the performance of the standard six-year graduation rate method with that of absorbing Markov chains. Through the analysis, we highlight significant limitations w...
Previous studies have used single-state absorbing Markov chain in prediction of manpower systems where retired staff and dropout are lumped together. In this study, we examine the necessity of separating the two. This is achieved using... more
Previous studies have used single-state absorbing Markov chain in prediction of manpower systems where retired staff and dropout are lumped together. In this study, we examine the necessity of separating the two. This is achieved using multi--absorbing states Markov chain. This method gives a clearer picture on how wastages occur in academic manpower systems.
This paper describes a new and simple random walk mobility model that simplifies the two-dimensional Markov chain based on the properties of symmetry and lumped process. Compared to various other approaches, the proposed approach... more
This paper describes a new and simple random walk mobility model that simplifies the two-dimensional Markov chain based on the properties of symmetry and lumped process. Compared to various other approaches, the proposed approach significantly reduces the complexity of the model by reducing the computing states. Based on this model, the location update rate and dwell time can be easily
Passengers on a transit network with common lines are often faced with the problem of choosing between either to board the arriving bus or to wait for a faster one. Many assignment models are based on the classical assumption that at a... more
Passengers on a transit network with common lines are often faced with the problem of choosing between either to board the arriving bus or to wait for a faster one. Many assignment models are based on the classical assumption that at a given stop passengers board the first arriving carrier of a certain subset of the available lines, often referred to as the attractive set. In this case, it has been shown that, if the headway distributions are exponential, then an optimal subset of lines minimizing the passenger travel time can be easily determined. However, when online information on future arrivals of buses are posted at the stop, it is unlikely that the above classical assumption holds. In this case, passengers may choose to board a line that offers the best combination of displayed waiting time and expected travel time to their destination once boarded. In this paper, we propose a general framework for determining the probability of boarding each line available at a stop when onl...
The estimation of platform waiting time has so far received little attention. This research aimed to estimate platform waiting time distributions on the London Underground, considering travel time variability by using smart card data that... more
The estimation of platform waiting time has so far received little attention. This research aimed to estimate platform waiting time distributions on the London Underground, considering travel time variability by using smart card data that were supplemented by performance reports. The on-train and ticket gate to platform walking times were assumed to be normally distributed and were matched with the trip time recorded by the smart cards to estimate the platform waiting time distribution. The stochastic frontier model was used, and its parameters were estimated by the maximum likelihood method. The cost frontier function was used to represent the relation between the travel time recorded in the smart card data as an output and the on-train time and walking time between the ticket gate and the platform as inputs. All estimated parameters were statistically significant, as shown by p-values. Comparing the travel time values estimated by the proposed model with the times recorded recorde...
Unmanned aerial vehicles, used and developed initially in the military field, have experienced profound changes in recent years and are increasingly used in the civilian field. Recognized as drones, they are most often used in the civil... more
Unmanned aerial vehicles, used and developed initially in the military field, have experienced profound changes in recent years and are increasingly used in the civilian field. Recognized as drones, they are most often used in the civil and military domains. They are used for firefighting, rescue as well as in specific applications such as surveillance and attack. The formation flight is the most used because it allows a judicious distribution of the tasks and greatly improves the efficiency of the drones (principle of the attack in pack, carnivorous animals). This will raise the issue of coordination and strategy, as well as the type of operation (master /slave, ...). The type and quality of optimal information also remain to be defined.The increased use of these cooperative systems in hazardous environments makes their reliability essential to prevent any catastrophic event. Overall performance of the drone fleet should be ensured, despite possible degradation of components or any...
The Physical or Mathematical behaviour of any system may be represented by describing all the different states it may occupy and by indicating how it moves among these states. In this study, the computation of the elements of the... more
The Physical or Mathematical behaviour of any system may be represented by describing all the different states it may occupy and by indicating how it moves among these states. In this study, the computation of the elements of the reachability matrix are separated into different categories depending on the classification of the initial and terminal states in such way that both states are recurrent and belong to the same closed communicating class, and both states are recurrent but belong to different closed communicating classes, when state is recurrent and state is transient. Hence, when both states are transient has been investigated in order to provide some insight into the performance measures in Absorption Probabilities for close and open classification group of states in Markov chain. Our quest is to obtain probabilities of moving from transient states to one or more of the closed communicating classes and also, to extract useful information in the context of Markov chains that have no transient states. The matrix operations and principles are used with the help of some existing equations and formulas in Markov chain to combine all states in an irreducible recurrent set into a single state, an absorbing state, and compute the probability of entering this state from transient state. Performance measures such as the probability that state is reached before state given state as the starting state, the probability that state is reached before state and the matrix of absorption probability are obtained.