1 citations · 3 across the 28 of their papers we have counts for
32 papers
Capital Costs Protect the Network: Mining Gap Dynamics in Proof-of-Work Blockchains Under a Stochastic Mempool
Hasan Selçuk Kılıç, Nail Akar
Proof-of-Work blockchains increasingly rely on transaction fees to keep miners engaged as block subsidies decline. An immediate outcome of this is that miners may sit idle at the s…
Minimizing Age of Incorrect Information in Pull-Based Remote Estimation of a Markov Source
Ismail Cosandal, Sennur Ulukus, Nail Akar
In this paper, we consider a discrete-time pull-based remote estimation system involving an information source and a remote monitor where the information source is a finite-state i…
Distribution of Age of Information in the Erlang Loss System
Nail Akar, Sennur Ulukus
In this paper, we study the exact distributions of the age of information (AoI) and peak AoI (PAoI) in a bufferless setting in which time-stamped updates, or processed tasks, gener…
Squeezing the Most Out of Preemption for AoI Minimization: Single-source Case
Nail Akar, Mohammad Moltafet, Sennur Ulukus +2
In this work, we study a single-source single-server continuous-time status update system where the updates arrive according to a Poisson process and update service times are gener…
Dual-Regime Absorbing Markov Chain Theory in Remote Estimation: Age-Minimizing Push Policies
Ismail Cosandal, Sennur Ulukus, Nail Akar
For a remote estimation system, we study the optimization of age of incorrect information (AoII), which is a recently proposed semantic-aware information freshness metric. In parti…
When and Which Sensor to Observe? Timely Tracking of a Joint Markov Source
Ismail Cosandal, Sennur Ulukus, Nail Akar
We investigate the problem of remote estimation (at a monitor) of a discrete-time joint Markov process with individual components which can be observed with dedicated sensors. At a…
Preemption Revisited: Multi-Threshold Preemption Policies for AoI Minimization
Sahan Liyanaarachchi, Sennur Ulukus, Nail Akar
The study of optimal preemption policies for status update systems has been a recurring topic in the age of information (AoI) literature, where threshold-based structures have been…
Beyond Martingale Estimators: Structured Estimators for Maximizing Information Freshness in Query-Based Update Systems
Sahan Liyanaarachchi, Sennur Ulukus, Nail Akar
This paper investigates information freshness in a remote estimation system in which the remote information source is a continuous-time Markov chain (CTMC). For such systems, estim…
Multi-Stage Structured Estimators for Information Freshness
Sahan Liyanaarachchi, Sennur Ulukus, Nail Akar
Most of the contemporary literature on information freshness solely focuses on the analysis of freshness for martingale estimators, which simply use the most recently received upda…
Utilizing the Perceived Age to Maximize Freshness in Query-Based Update Systems
Sahan Liyanaarachchi, Sennur Ulukus, Nail Akar
Query-based sampling has become an increasingly popular technique for monitoring Markov sources in pull-based update systems. However, most of the contemporary literature on this a…
Age of Information with Age-Dependent Server Selection
Nail Akar, Ismail Cosandal, Sennur Ulukus
In this paper, we consider a single-source multi-server generate-at-will discrete-time non-preemptive status update system where update packets are transmitted using {\em only one}…
Semi-Markov Decision Process Framework for Age of Incorrect Information Minimization
Ismail Cosandal, Sennur Ulukus, Nail Akar
For a remote estimation system, we study age of incorrect information (AoII), which is a recently proposed semantic-aware freshness metric. In particular, we assume an information…
Absorbing Markov Chain-Based Analysis of Age of Information in Discrete-Time Dual-Queue Systems
Yifan Feng, Nail Akar, Zhengchuan Chen +1
Status update systems require the timely collection of sensing information for which deploying multiple sensors/servers to obtain diversity gains is considered as a promising solut…
Structured Estimators: A New Perspective on Information Freshness
Sahan Liyanaarachchi, Sennur Ulukus, Nail Akar
In recent literature, when modeling for information freshness in remote estimation settings, estimators have been mainly restricted to the class of martingale estimators, meaning t…
Minimizing Functions of Age of Incorrect Information for Remote Estimation
Ismail Cosandal, Sennur Ulukus, Nail Akar
The age of incorrect information (AoII) process which keeps track of the time since the source and monitor processes are in sync, has been extensively used in remote estimation pro…
How to Maximize Efficiency in Systems with Exhausted Workers
Elif Beray Sariisik, Melih Bastopcu, Nail Akar +1
We consider the problem of assigning tasks efficiently to a set of workers that can exhaust themselves as a result of processing tasks. If a worker is exhausted, it will take a lon…
Which Sensor to Observe? Timely Tracking of a Joint Markov Source with Model Predictive Control
Ismail Cosandal, Sennur Ulukus, Nail Akar
In this paper, we investigate the problem of remote estimation of a discrete-time joint Markov process using multiple sensors. Each sensor observes a different component of the joi…
Fully Decentralized Computation Offloading in Priority-Driven Edge Computing Systems
Shubham Aggarwal, Melih Bastopcu, Muhammad Aneeq uz Zaman +3
We develop a novel framework for fully decentralized offloading policy design in multi-access edge computing (MEC) systems. The system comprises power-constrained user equipmen…
Double Spending Analysis of Nakamoto Consensus for Time-Varying Mining Rates with Ruin Theory
Mustafa Doger, Sennur Ulukus, Nail Akar
Theoretical guarantees for double spending probabilities for the Nakamoto consensus under the -deep confirmation rule have been extensively studied for zero/bounded network dela…
Joint Age-State Belief is All You Need: Minimizing AoII via Pull-Based Remote Estimation
Ismail Cosandal, Sennur Ulukus, Nail Akar
Age of incorrect information (AoII) is a recently proposed freshness and mismatch metric that penalizes an incorrect estimation along with its duration. Therefore, keeping track of…
Scheduling Policies in a Multi-Source Status Update System with Dedicated and Shared Servers
Sahan Liyanaarachchi, Sennur Ulukus, Nail Akar
Use of multi-path network topologies has become a prominent technique to assert timeliness in terms of age of information (AoI) and to improve resilience to link disruptions in com…
Modeling Interfering Sources in Shared Queues for Timely Computations in Edge Computing Systems
Nail Akar, Melih Bastopcu, Sennur Ulukus +1
Most existing stochastic models on age of information (AoI) focus on a single shared server serving status update packets from sources where each packet update stream is Pois…
Multi-Threshold AoII-Optimum Sampling Policies for CTMC Information Sources
Ismail Cosandal, Nail Akar, Sennur Ulukus
We study push-based sampling and transmission policies for a status update system consisting of a general finite-state continuous-time Markov chain (CTMC) information source with k…
Cyclic Scheduler Design for Minimizing Age of Information in Massive Scale Networks Susceptible to Packet Errors
Sahan Liyanaarachchi, Sennur Ulukus, Nail Akar
In multi-source status update systems, sources need to be scheduled appropriately to maintain timely communication between each of the sources and the monitor. A cyclic schedule is…