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Towards Sustainable Internet of Underwater Things: UAV-aided Energy Efficient Wake-up Solutions

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arXiv 2022年

作者： Muzzammil, Muhammad Kouzayha, Nour Saeed, Nasir Al-Naffouri, Tareq Y. College of Underwater Acoustic Engineering Harbin Engineering University China Division of Computer Electrical and Mathematical Sciences and Engineering King Abdullah University of Science and Technology Thuwal23955-6900 Saudi Arabia Remote Sensing Unit Department of Electrical Engineering Northern Border University Arar Saudi Arabia

With the advancements in underwater wireless communications, internet of underwater things (IoUT) realization is inevitable to enable many practical applications, such as exploring ocean resources, ocean monitoring, underwater navigation, and surveillance. The IoUT network comprises battery-operated sensor nodes, and replacing or charging such batteries is challenging due to the harsh ocean environment. Hence, an energy-efficient IoUT network development becomes vital to improve the network lifetime. Therefore, this paper proposes unmanned aerial vehicle (UAV)-aided energy-efficient wake-up designs to activate the underwater IoT nodes on-demand and reduce their energy consumption. Specifically, the UAV communicates with water surface nodes, i.e., buoys, to send wake-up signals to activate the IoUT sensor nodes from sleep mode. We present three different technologies to enable underwater wake-up: acoustic, optical, and magnetic induction-based solutions. Moreover, we verify the significance of each technology through simulations using the performance metrics of received power and lifetime. Also, the results of the proposed on-demand wake-up approach are compared to conventional duty cycling, showing the superior performance of the proposed schemes. Finally, we present some exciting research challenges and future directions. © 2022, CC BY.

关键词： Sensor nodes

Unbiased estimation of the gradient of the log-likelihood for a class of continuous-time state-space models

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arXiv 2021年

作者： Ballesio, Marco Jasra, Ajay Computer Electrical and Mathematical Sciences and Engineering Division King Abdullah University of Science and Technology Thuwal23955 Saudi Arabia

In this paper, we consider static parameter estimation for a class of continuous-time state-space models. Our goal is to obtain an unbiased estimate of the gradient of the log-likelihood (score function), which is an estimate that is unbiased even if the stochastic processes involved in the model must be discretized in time. To achieve this goal, we apply a doubly randomized scheme (see, e.g., [13, 14]), that involves a novel coupled conditional particle filter (CCPF) on the second level of randomization [15]. Our novel estimate helps facilitate the application of gradient-based estimation algorithms, such as stochastic-gradient Langevin descent. We illustrate our methodology in the context of stochastic gradient descent (SGD) in several numerical examples and compare with the Rhee & Glynn estimator [22, 23]. © 2021, CC BY.

关键词： Monte Carlo methods

Kalman Filter Design for Intermittent Optical Wireless Communication Systems on Time Scales

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Kalman Filter Design for Intermittent Optical Wireless Commu...

International Conference on Systems and Control (ICSC)

作者： Wenqi Cai Bacem Ben Nasser Mohamed Djemai Taous Meriem Laleg-Kirati Electrical and Computer Engineering Program King Abdullah University of Science and Technology (KAUST) Thuwal Saudi Arabia INSA Hauts-de-France LAMIH UMR CNRS 8201 UPHF QUARTZ Laboratory EA 7393 ENSEA INRIA Paris Saclay France

ISBN: (数字)9781665465076

ISBN: (纸本)9781665465083

Time-scale theory, due to its ability to unify the continuous and discrete cases, allows handling intractable non-uniform measurements, such as intermittent received signals. In this work, we address the state estimation problem of a vibration-induced intermittent optical wireless communication (OWC) system by designing a Kalman filter on time scales. First, the algorithm of the time-scale Kalman filter is introduced and a numerical example is given for illustration. Then the studied intermittent OWC system is presented, and experimental data are collected to determine the time scale's form, which has bounded graininess (a.k.a, bounded time jumps). Finally, we design a Kalman filter on the previously defined time scale for the intermittent OWC system and critically analyzed its estimation performance. Moreover, the obtained conclusions are further validated on a reference system. The simulation results corroborate that the time-scale Kalman filtering technique is considerably promising to solve the state estimation problem with non-uniform measurements. This study reveals for the first time the feasibility of applying the time-scale Kalman filter theory to practical applications.

关键词： Wireless communication Optical filters Integrated optics Optical design Filtering Simulation Current measurement

Low-coherence semiconductor light sources: devices and applications

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npj Nanophotonics

npj Nanophotonics 2024年第1期1卷 1-19页

作者： Hang Lu Omar Alkhazragi Yue Wang Nawal Almaymoni Wenbo Yan Wahyu Hendra Gunawan Heming Lin Tae-Yong Park Tien Khee Ng Boon S. Ooi Photonics Laboratory Electrical and Computer Engineering Program Division of Computer Electrical and Mathematical Sciences and Engineering (CEMSE) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Kingdom of Saudi Arabia

Since the invention of the laser, there have been countless applications that were made possible or improved through exploiting its multitude of unique advantages. Most of these advantages are mainly due to the high degree of coherence of the laser light, which makes it directional and spectrally pure. Nevertheless, many fields require a moderate degree of temporal or spatial coherence, making conventional lasers unsuitable for these applications. This has brought about a great interest in partially coherent light sources, especially those based on semiconductor devices, given their efficiency, compactness, and high-speed operation. Here, we review the development of low-coherence semiconductor light sources, including superluminescent diodes, highly multimode lasers, and random lasers, and the wide range of applications in which they have been deployed. We highlight how each of these applications benefsits from a lower degree of coherence in space and/or time. We then discuss future potential applications that can be enabled using new types of low-coherence light.

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Metal–organic frameworks modified electrode for H₂S detections in biological and pharmaceutical agents

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MedComm - Biomaterials and Applications

MedComm - Biomaterials and Applications 2023年第3期2卷

作者： Durmus, Ceren Arul, Ponnusamy Alhaji, A. Shekhah, Osama Mani, Veerappan Eddaoudi, Mohamed Salama, Khaled Nabil Sensors Lab Advanced Membranes and Porous Materials Center Computer Electrical and Mathematical Science and Engineering Division King Abdullah University of Science and Technology (KAUST) Thuwal Saudi Arabia Department of Chemical Engineering and Biotechnology Institute of Biochemical and Biomedical Engineering National Taipei University of Technology Taipei Taiwan Physical Sciences and Engineering Division Functional Materials Design Discovery and Development Research Group (FMD3) Advanced Membranes and Porous Materials Centre (AMPMC) King Abdullah University of Science and Technology (KAUST) Jeddah Saudi Arabia

The development of hydrogen sulfide (H2S) sensors is essential to address H2S-related pharmacology since slow-releasing H2S medications have been identified to be prospective options for cancer treatments. Here, we de... 详细信息

The development of hydrogen sulfide (H₂S) sensors is essential to address H₂S-related pharmacology since slow-releasing H₂S medications have been identified to be prospective options for cancer treatments. Here, we described an electrochemical sensor for highly selective and sensitive detection of aqueous H₂S, using a thin film of fumarate-based face-centered cubic (fcu)-based metal–organic frameworks (fum-fcu-MOF) modified on laser-scribed graphene (LSGE). The fum-fcu-MOF has shown a strong affinity and chemical stability to H₂S analysis. The electrochemical and H₂S catalytic properties were studied for fum-fcu-MOF/LSGE. An amperometry and differential pulse voltammetry techniques were demonstrated to validate the sensor. The resulting sensor delivered acceptable analytical parameters in terms of;detection limit (3.0 µM), dynamic range (10–500 µM), reproducibility, and stability (94.7%). The sensor's practical validity was demonstrated in bacterial cells and H₂S-releasing drug, where the sensor was able to monitor the continuous release of in-situ H₂S. The pharmacokinetics of a slow releasing H₂S donor is accessed at different time intervals and different concentration levels. Our research indicate that this fum-fcu-MOF based H₂S sensor holds potential in understanding pharmacokinetics of H₂S releasing drugs. © 2023 The Authors. MedComm – Biomaterials and Applications published by John Wiley & Sons Australia, Ltd on behalf of Sichuan International Medical Exchange & Promotion Association (SCIMEA).

关键词： H2S pharmacology hydrogen sulfide metal organic frameworks

Multilevel Estimation of Normalization Constants Using the Ensemble Kalman-Bucy Filter

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arXiv 2021年

作者： Ruzayqat, Hamza M. Chada, Neil K. Jasra, Ajay Computer Electrical and Mathematical Sciences and Engineering Division King Abdullah University of Science and Technology Thuwal23955 Saudi Arabia

In this article we consider the application of multilevel Monte Carlo, for the estimation of normalizing constants. In particular we will make use of the filtering algorithm, the ensemble Kalman-Bucy filter (EnKBF), which is an N-particle representation of the Kalman-Bucy filter (KBF). The EnKBF is of interest as it coincides with the optimal filter in the continuous-linear setting, i.e. the KBF. This motivates our particular setup in the linear setting. The resulting methodology we will use is the multilevel ensemble Kalman-Bucy filter (MLEnKBF). We provide an analysis based on deriving Lq-bounds for the normalizing constants using both the single-level, and the multilevel algorithms, which is largely based on previous work deriving the MLEnKBF [10]. Our results will be highlighted through numerical results, where we firstly demonstrate the error-to-cost rates of the MLEnKBFs comparing it to the EnKBF on a linear Gaussian model. Our analysis will be specific to one variant of the MLEnKBF, whereas the numerics will be tested on different variants. We also exploit this methodology for parameter estimation, where we test this on the models arising in atmospheric sciences, such as the stochastic Lorenz 63 and 96 *** Codes 60G35, 62F15, 65C05, 62M20 © 2021, CC BY.

关键词： Parameter estimation

On unbiased score estimation for partially observed diffusions

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arXiv 2021年

作者： Heng, Jeremy Houssineau, Jeremie Jasra, Ajay ESSEC Business School University of Warwick Computer Electrical and Mathematical Sciences and Engineering Division King Abdullah University of Science and Technology

We consider the problem of statistical inference for a class of partially-observed diffusion processes, with discretely-observed data and finite-dimensional parameters. We construct unbiased estimators of the score function, i.e. the gradient of the log-likelihood function with respect to parameters, with no time-discretization bias. These estimators can be straightforwardly employed within stochastic gradient methods to perform maximum likelihood estimation or Bayesian inference. As our proposed methodology only requires access to a time-discretization scheme such as the Euler-Maruyama method, it is applicable to a wide class of diffusion processes and observation models. Our approach is based on a representation of the score as a smoothing expectation using Girsanov theorem, and a novel adaptation of the randomization schemes developed in Mcleish [2011], Rhee and Glynn [2015], Jacob et al. [2020a]. This allows one to remove the time-discretization bias and burn-in bias when computing smoothing expectations using the conditional particle filter of Andrieu et al. [2010]. Central to our approach is the development of new couplings of multiple conditional particle filters. We prove under assumptions that our estimators are unbiased and have finite variance. The methodology is illustrated on several challenging applications from population ecology and *** Codes 62M05 © 2021, CC BY.

关键词： Monte Carlo methods

Choosing a Suitable Requirement Prioritization Method: A Survey

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arXiv 2024年

作者： Alhenawi, Esraa Awawdeh, Shatha Khurma, Ruba Abu García-Arenas, Maribel Castillo, Pedro A. Hudaib, Amjad Faculty of Information Technology Zarqa University Zarqa Jordan Applied Science Private University Amman Jordan MEU Research Unit Faculty of Information Technology Middle East University Amman11831 Jordan Department of Computer Engineering Automation and Robotics University of Granada Granada Spain King Abdullah II School for Information Technology The University of Jordan Amman Jordan

Software requirements prioritization plays a crucial role in software development. It can be viewed as the process of ordering requirements by determining which requirements must be done first and which can be done later. Powerful requirements prioritization techniques are of paramount importance to finish the implementation on time and within budget. Many factors affect requirement prioritization such as stakeholder expectations, complexity, dependency, scalability, risk, and cost. Therefore, finding the proper order of requirements is a challenging process. Hence, different types of requirements prioritization techniques have been developed to support this task. In this survey, we propose a novel classification that can classify the prioritization techniques under two major classes: relative and exact prioritization techniques class, where each class is divided into two subclasses. We depend in our classification on the way the value of ranking is given to the requirement, either explicitly as a specific value in the case of the exact prioritization techniques class, or implicitly in the case of the Relative prioritization technique class. An overview of fifteen different requirements prioritization techniques are presented and organized according to the proposed classification criteria’s. Moreover, we make a comparison between methods that are related to the same subclass to analyze their strengths and weaknesses. Based on the comparison results, the properties for each proposed subclass of techniques are identified. Depending on these properties, we present some recommendations to help project managers in the process of selecting the most suitable technique to prioritize requirements based on their project characteristics (number of requirements, time, cost, and accuracy). © 2024, CC BY.

关键词： Requirements engineering

Sequential Markov Chain Monte Carlo for Lagrangian Data Assimilation with Applications to Unknown Data Locations

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arXiv 2023年

作者： Ruzayqat, Hamza Beskos, Alexandros Crisan, Dan Jasra, Ajay Kantas, Nikolas Applied Mathematics and Computational Science Program Computer Electrical and Mathematical Sciences and Engineering Division King Abdullah University of Science and Technology Thuwal23955-6900 Saudi Arabia Department of Statistical Science University College London LondonWC1E 6BT United Kingdom Department of Mathematics Imperial College London LondonSW7 2AZ United Kingdom

We consider a class of high-dimensional spatial filtering problems, where the spatial locations of observations are unknown and driven by the partially observed hidden signal. This problem is exceptionally challenging as not only is high-dimensional, but the model for the signal yields longer-range time dependencies through the observation locations. Motivated by this model we revisit a lesser-known and provably convergent computational methodology from [4, 11, 28] that uses sequential Markov Chain Monte Carlo (MCMC) chains. We extend this methodology for data filtering problems with unknown observation locations. We benchmark our algorithms on Linear Gaussian state space models against competing ensemble methods and demonstrate a significant improvement in both execution speed and accuracy. Finally, we implement a realistic case study on a high-dimensional rotating shallow water model (of about 104 - 105 dimensions) with real and synthetic data. The data is provided by the National Oceanic and Atmospheric Administration (NOAA) and contains observations from ocean drifters in a domain of the Atlantic Ocean restricted to the longitude and latitude intervals [-51◦,-41◦], [17◦,27◦] *** Codes 62M20, 60G35, 60J20, 94A12, 93E11, 65C40 © 2023, CC BY.

关键词： Location