Sindri Magnússon

ORCID: 0000-0002-6617-8683
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About
Contact & Profiles
Research Areas
  • Stochastic Gradient Optimization Techniques
  • Sparse and Compressive Sensing Techniques
  • Smart Grid Energy Management
  • Optimal Power Flow Distribution
  • Privacy-Preserving Technologies in Data
  • Distributed Control Multi-Agent Systems
  • Microgrid Control and Optimization
  • Energy Efficient Wireless Sensor Networks
  • Advanced MIMO Systems Optimization
  • Cooperative Communication and Network Coding
  • Reinforcement Learning in Robotics
  • Optimization and Search Problems
  • Distributed Sensor Networks and Detection Algorithms
  • Advanced Memory and Neural Computing
  • Mobile Ad Hoc Networks
  • IoT and Edge/Fog Computing
  • Indoor and Outdoor Localization Technologies
  • Power Line Communications and Noise
  • Electric Power System Optimization
  • Power System Optimization and Stability
  • Age of Information Optimization
  • Machine Learning and ELM
  • Fault Detection and Control Systems
  • Advanced Wireless Network Optimization
  • Complexity and Algorithms in Graphs

Stockholm University
2019-2025

Kista Photonics Research Center
2023-2025

Harvard University
2017-2020

KTH Royal Institute of Technology
2014-2020

Harvard University Press
2019-2020

University of Iceland
2020

Linnaeus University
2014

Bispebjerg Hospital
2003

University of Copenhagen
2003

The optimal power-flow (OPF) problem, which plays a central role in operating electrical networks, is considered. problem nonconvex and is, fact, NP hard. Therefore, designing efficient algorithms of practical relevance crucial, though their global optimality not guaranteed. Existing semidefinite programming relaxation-based approaches are restricted to OPF problems where zero duality holds. In this paper, an novel method address the general investigated. proposed based on alternating...

10.1109/tcns.2015.2399192 article EN IEEE Transactions on Control of Network Systems 2015-04-20

Nonconvex and structured optimization problems arise in many engineering applications that demand scalable distributed solution methods. The study of the convergence properties these methods is, general, difficult due to nonconvexity problem. In this paper, two combine fast augmented Lagrangian-based with separability alternating are investigated. first method is adapted from classic quadratic penalty function called direction (ADPM). Unlike original method, where single-step optimizations...

10.1109/tcns.2015.2476198 article EN IEEE Transactions on Control of Network Systems 2015-09-03

The increased penetration of volatile renewable energy into distribution networks necessities more efficient distributed voltage control. In this paper, we design feedback control algorithms where each bus can inject both active and reactive power the grid to regulate voltages. law on is only based local measurements communication its physical neighbors. Moreover, buses perform their updates asynchronously without receiving information from neighbors for periods time. algorithm enforces hard...

10.1109/tsg.2020.2970768 article EN publisher-specific-oa IEEE Transactions on Smart Grid 2020-01-31

In distributed optimization and machine learning, multiple nodes coordinate to solve large problems. To do this, the need compress important algorithm information bits so that it can be communicated over a digital channel. The communication time of these algorithms follows complex interplay between a) algorithm's convergence properties, b) compression scheme, c) transmission rate offered by We explore relationships for general class linearly convergent algorithms. particular, we illustrate...

10.1109/tsp.2020.3031073 article EN IEEE Transactions on Signal Processing 2020-01-01

Distributed optimization increasingly plays a central role in economical and sustainable operation of cyber-physical systems. Nevertheless, the complete potential technology has not yet been fully exploited practice due to communication limitations posed by real-world infrastructures. This work investigates fundamental properties distributed based on gradient methods, where information is communicated using limited number bits. In particular, general class quantized methods are studied,...

10.1109/tac.2017.2743678 article EN publisher-specific-oa IEEE Transactions on Automatic Control 2017-08-23

Internet of Underwater Things (IoUT) have gained rapid momentum over the past decade with applications spanning from environmental monitoring and exploration, defence applications, etc. The traditional IoUT systems use machine learning (ML) approaches which cater needs reliability, efficiency timeliness. However, an extensive review various studies conducted highlight significance data privacy security in frameworks as a predominant factor achieving desired outcomes mission critical...

10.1109/iotm.001.2200067 article EN IEEE Internet of Things Magazine 2022-12-01

In electricity distribution networks, the increasing penetration of renewable energy generation necessitates faster and more sophisticated voltage controls. Unfortunately, recent research shows that local control fails in achieving desired regulation, unless there is communication between controllers. However, infrastructure for systems less reliable ubiquitous compared to bulk transmission system. this paper, we design distributed uses limited communication. That is, only neighboring buses...

10.1109/tcns.2019.2905091 article EN publisher-specific-oa IEEE Transactions on Control of Network Systems 2019-03-14

Despite the huge success of reinforcement learning (RL) in solving many difficult problems, its Achilles heel has always been sample inefficiency. On other hand, RL, taking advantage prior knowledge, intentionally or unintentionally, usually avoided, so that, training an agent from scratch is common. This not only causes inefficiency but also endangers safety –especially during exploration. In this paper, we help learn environment by using pre-existing (but necessarily exact complete)...

10.1016/j.ins.2024.120182 article EN cc-by Information Sciences 2024-01-23

Parallel stochastic gradient methods are gaining prominence in solving large-scale machine learning problems that involve data distributed across multiple nodes. However, obtaining unbiased gradients, which have been the focus of most theoretical research, is challenging many applications. The estimations easily become biased, for example, when gradients compressed or clipped, shuffled, and meta-learning reinforcement learning. In this work, we establish worst-case bounds on parallel...

10.1109/tcns.2025.3527255 article EN IEEE Transactions on Control of Network Systems 2025-01-01

With the rise of low-cost launches, miniaturized space technology, and commercialization, cost missions has dropped, leading to a surge in flexible Earth observation satellites. This increased demand for complex diverse imaging products requires addressing multi-objective optimization practice. To this end, we propose agile satellite scheduling problem (MOAEOSSP) model introduce reinforcement learning-based grey wolf (RLMOGWO) algorithm. It aims maximize efficiency while minimizing energy...

10.1080/17538947.2025.2458024 article EN cc-by-nc International Journal of Digital Earth 2025-02-02

Abstract Predicting failures and maintenance time in predictive is challenging due to the scarcity of comprehensive real-world datasets, among those available, few are series format. This paper introduces a real-world, multivariate dataset collected exclusively from single anonymized engine component (Component X) across fleet SCANIA trucks. The includes operational data, repair records, specifications related Component X while maintaining confidentiality through anonymization. It...

10.1038/s41597-025-04802-6 article EN cc-by Scientific Data 2025-03-24

Dual decomposition methods are among the most prominent approaches for finding primal/dual saddle point solutions of resource allocation optimization problems. To deploy these in emerging Internet things networks, which will often have limited data rates, it is important to understand communication overhead they require. Motivated by this, we introduce and explore two measures complexity dual identify efficient algorithms. The first measure <inline-formula...

10.1109/jstsp.2018.2848718 article EN publisher-specific-oa IEEE Journal of Selected Topics in Signal Processing 2018-06-18

As electric power system operators shift from conventional energy to renewable sources, distribution systems will experience increasing fluctuations in supply. These present the need not only design online decentralized allocation algorithms, but also characterize how effective they are given fast-changing consumer demand and generation. In this paper, we an dual descent (OD3) algorithm determine (in worst case) much of observed social welfare can be explained by generation capacity demand....

10.1109/tpwrs.2017.2709544 article EN publisher-specific-oa IEEE Transactions on Power Systems 2017-05-29

In parallel and distributed machine learning multiple nodes or processors coordinate to solve large problems. To do this, the need compress important algorithm information bits so they can communicate. The goal of this paper is explore how we maintain convergence algorithms under such compression. particular, consider a general class linearly convergent parallel/distributed illustrate design quantizers compressing communicated few while still preserving linear convergence. We our results on...

10.1109/ieeeconf44664.2019.9049052 article EN 2019-11-01

Internet of Underwater Things (IoUT) have gained rapid momentum over the past decade with applications spanning from environmental monitoring and exploration, defence applications, etc. The traditional IoUT systems use machine learning (ML) approaches which cater needs reliability, efficiency timeliness. However, an extensive review various studies conducted highlight significance data privacy security in frameworks as a predominant factor achieving desired outcomes mission critical...

10.48550/arxiv.2207.13976 preprint EN cc-by arXiv (Cornell University) 2022-01-01

Noisy gradient algorithms have emerged as one of the most popular for distributed optimization with massive data. Choosing proper step-size schedules is an important task to tune in good performance. For attain fast convergence and high accuracy, it intuitive use large step-sizes initial iterations when noise typically small compared algorithm-steps, reduce algorithm progresses. This intuition has been confirmed theory practice stochastic descent. However, similar results are lacking other...

10.1109/tsp.2023.3237392 article EN IEEE Transactions on Signal Processing 2023-01-01

The wide integration of inverter based renewable energy sources (RESs) in modern grids may cause severe voltage violation issues due to high stochastic fluctuations RESs. Existing centralized approaches can achieve optimal results for regulation, but they have communication burdens; existing decentralized methods only require local information, cannot results. Deep reinforcement learning (DRL) are effective deal with uncertainties, it is difficult guarantee secure constraints DRL training....

10.1109/tste.2023.3341632 article EN cc-by IEEE Transactions on Sustainable Energy 2023-12-12

This paper presents a description of real-world, multivariate time series dataset collected from an anonymized engine component (called Component X) fleet trucks SCANIA, Sweden. includes diverse variables capturing detailed operational data, repair records, and specifications while maintaining confidentiality by anonymization. It is well-suited for range machine learning applications, such as classification, regression, survival analysis, anomaly detection, particularly when applied to...

10.48550/arxiv.2401.15199 preprint EN arXiv (Cornell University) 2024-01-26

Distributed control and decision making increasingly play a central role in economical sustainable operation of cyber-physical systems. Nevertheless, the full potential technology has not yet been fully exploited practice due to communication limitations real-world infrastructures. This work investigates fundamental properties gradient methods for distributed optimization, where information is communicated at every iteration, when using limited number bits. In particular, general class...

10.1109/acc.2016.7525116 article EN 2022 American Control Conference (ACC) 2016-07-01

In electricity distribution networks, the increasing penetration of renewable energy generation necessitates faster and more sophisticated voltage controls. Unfortunately, recent research shows that local control fails in achieving desired regulation, unless there is some communication between controllers. However, infrastructure for systems are less reliable ubiquitous as compared to bulk transmission system. this paper, we design distributed use limited communication. That is, only...

10.1016/j.ifacol.2017.08.001 article EN IFAC-PapersOnLine 2017-07-01

An important task in the Internet of Things (IoT) is field monitoring, where multiple IoT nodes take measurements and communicate them to base station or cloud for processing, inference, analysis. When are high-dimensional (e.g., videos time-series data), networks with limited bandwidth low-power devices may not be able support such frequent transmissions high data rates. To ensure communication efficiency, this article proposes model measurement compression at inference as a deep neural...

10.1109/mcom.001.2000015 article EN IEEE Communications Magazine 2020-09-01

The emergence of big data has caused a dramatic shift in the operating regime for optimization algorithms. performance bottleneck, which used to be computations, is now often communications. Several gradient compression techniques have been proposed reduce communication load at price loss solution accuracy. Recently, it shown how errors can compensated algorithm improve Even though convergence guarantees error-compensated algorithms established, there very limited theoretical support...

10.1109/tsp.2020.3048229 article EN IEEE Transactions on Signal Processing 2020-12-30

Distributed resource allocation is a central task in network systems such as smart grids, water distribution networks, and urban transportation systems. When solving problems practice it often important to have non-asymptotic feasibility guarantees for the iterates, since overall-location of resources easily causes break down. In this paper, we develop distributed reallocation algorithm where every iteration produces feasible allocation. The fully sense that nodes communicate only with...

10.1109/cdc45484.2021.9683783 article EN 2021 60th IEEE Conference on Decision and Control (CDC) 2021-12-14
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