11,218 results on '"Physical system"'
Search Results
2. Development of Compact and Robust Physical System for Strontium Optical Lattice Clock.
- Author
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Chen, Yingxin, Zhou, Chihua, Tan, Wei, Guo, Feng, Zhao, Guodong, Xia, Jian, Meng, Junwei, and Chang, Hong
- Subjects
ATOMIC clocks ,OPTICAL lattices ,STRONTIUM ,MAGNETIC shielding ,MAGNETIC field effects ,MAGNETICS - Abstract
Compact and robust optical clocks are significant in scientific research and engineering. Here, we present a physical system for a strontium atomic optical clock with dimensions of 465 mm × 588 mm × 415 mm and a weight of 66.6 kg. To date, this is one of the most compact physical systems ever reported. The application of the magnetic shielding box in this physical system allowed the effect of external magnetic field fluctuation on cold atoms to be negligible. The physical system passed rigorous environmental tests and remained operational. A wavelength meter integrated in this physical system could monitor the wavelengths of the incident laser, and it could automatically calibrate the wavelengths of all lasers using a microcomputer. This compact and robust physical system could be a hardware basis for demonstrating a portable optical clock or even a space optical clock. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
3. Security Vulnerabilities and Threats in Robotic Systems: A Comprehensive Review.
- Author
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Abed, Mustafa Salah, Al-Doori, Qusay F., Abdullah, Afrah Thamer, and Abdallah, Azhaar Akram
- Subjects
DIGITAL technology ,ROBOTICS ,SECURITY systems ,DATA security ,RELIABILITY in engineering ,NEUROREHABILITATION ,ROBOTS - Abstract
The recent digital revolution has resulted in robots being integrated more than ever into various domains, such as agriculture, healthcare, and the military. Robots are dedicated to serving, facilitating, and improving human life. However, the growing prevalence of robotics has brought to light the need for robust security measures. While unintentional accidents are inevitable, this paper focuses on the increasingly challenging problem of malicious cyber-attacks against robotic systems. One specific incident highlighting the severity of this issue occurred in 2022 when a healthcare robot was hacked, resulting in the misadministration of medication to several patients, leading to severe health complications and unnecessary loss of human lives. Such instances underscore the urgency of understanding the robotics domain's security vulnerabilities, threats, and consequences. In conclusion, this paper highlights the critical aspects of securing robotic systems in today's technologically advanced world. By identifying and analyzing the primary security vulnerabilities, this paper examines the primary security vulnerabilities, the type of application, then the impact of vulnerabilities; we can pave the way for effective security measures and ultimately ensure the safety and reliability of robotic systems. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
4. STRUCTURAL ANALYSES OF THE COMPOSITE MATERIAL FOR AUTONOMOUS MODULAR SYSTEM USED AS LATERAL MARK IN BRACKISH WATER HABITAT.
- Author
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Gabriela, Alexandra, Mihaela, Jomir, and Carmen, Mihai
- Subjects
- *
BRACKISH waters , *MATERIALS analysis , *WATERMARKS , *COMPOSITE materials , *OCEAN waves - Abstract
The safety of navigation and life in the risk areas adjacent to the coastal area, represent the central objective of the paper and meet the provisions of the European directive "in force." In this context, for defining the geometry of the autonomous modular system used as physical system for marking the fairway, mathematical prediction models were developed. The prediction of phenomena and functional characteristics for autonomous modular system was possible by using a specialized software, where the calculation conditions were for sea state maximum 6 Beaufort scale. The configurations were round geometric bodies generated by the rotation of a triangle around the straight line containing the largest side and two rectangular trapezoids joined at the large base and rotated around the side perpendicular to the bases, and the constraints were initiated on the submerged side of each system. The post-processing enabled the visualization of the results: the deformation, the Von Mises stress fields and the distribution of displacement vectors. The state of tension was calculated, resulting in values that fall within the range -5.96e+006 to 5.85e+007 N/m2, below the allowable strength of the material, so the composite material with textile matrix will resist to the distributed force imposed. Descriptions of the study, main problematic and used methods are discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
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5. Introduction to Simulink
- Author
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Hossain, Eklas and Hossain, Eklas
- Published
- 2022
- Full Text
- View/download PDF
6. The Use of E-Recruitment Process with the Comparison of Traditional Recruitment Process in Bangladesh: A Case Study on BRAC Bank Ltd.
- Author
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Md. Arifuzzaman, Md. Shoriful Islam, Md. Yeamin Masum, and Jannatul Shams Anonna
- Subjects
E-recruitment ,Traditional recruitment ,Physical system ,HRM ,Education ,Social Sciences - Abstract
This paper discusses the comparison of e-recruitment and traditional recruitment processes and their merits and demerits. The figure of this process is arranged in such a way that in the static equilibrium, the e-recruitment process takes the horizontal position, while the traditional recruitment process takes the vertical position. Here are presented the characteristics of both e-recruitment and traditional recruitment processes that are used in Bangladesh for attracting and selecting qualified candidates through the analysis of a case of BRAC Bank Ltd. Obtained results proved to be in accordance with the motion of the real physical system. The difference between the two processes is illustrated in the figure and the merits and demerits of the two processes are discussed in the table.
- Published
- 2023
- Full Text
- View/download PDF
7. Development of Compact and Robust Physical System for Strontium Optical Lattice Clock
- Author
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Yingxin Chen, Chihua Zhou, Wei Tan, Feng Guo, Guodong Zhao, Jian Xia, Junwei Meng, and Hong Chang
- Subjects
physical system ,compact and robust ,optical clock ,strontium atoms ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Compact and robust optical clocks are significant in scientific research and engineering. Here, we present a physical system for a strontium atomic optical clock with dimensions of 465 mm × 588 mm × 415 mm and a weight of 66.6 kg. To date, this is one of the most compact physical systems ever reported. The application of the magnetic shielding box in this physical system allowed the effect of external magnetic field fluctuation on cold atoms to be negligible. The physical system passed rigorous environmental tests and remained operational. A wavelength meter integrated in this physical system could monitor the wavelengths of the incident laser, and it could automatically calibrate the wavelengths of all lasers using a microcomputer. This compact and robust physical system could be a hardware basis for demonstrating a portable optical clock or even a space optical clock.
- Published
- 2024
- Full Text
- View/download PDF
8. Nature of an Engineered System: Illustrated from Engineering Artefacts and Complex Systems
- Author
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Sillitto, Hillary, Martin, James, Section editor, Metcalf, Gary S., editor, Kijima, Kyoichi, editor, and Deguchi, Hiroshi, editor
- Published
- 2021
- Full Text
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9. Cyber-Physical System—An Overview
- Author
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Someswara Rao, Chinta, Shiva Shankar, R., Murthy, K. V. S., Howlett, Robert J., Series Editor, Jain, Lakhmi C., Series Editor, Satapathy, Suresh Chandra, editor, Bhateja, Vikrant, editor, Mohanty, J. R., editor, and Udgata, Siba K., editor
- Published
- 2020
- Full Text
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10. Modified Asymptotic Method of Studying the Mathematical Model of Nonlinear Oscillations Under the Impact of a Moving Environment
- Author
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Pukach, Petro, Il’kiv, Volodymyr, Nytrebych, Zinovii, Vovk, Myroslava, Pukach, Pavlo, Kacprzyk, Janusz, Series Editor, Pal, Nikhil R., Advisory Editor, Bello Perez, Rafael, Advisory Editor, Corchado, Emilio S., Advisory Editor, Hagras, Hani, Advisory Editor, Kóczy, László T., Advisory Editor, Kreinovich, Vladik, Advisory Editor, Lin, Chin-Teng, Advisory Editor, Lu, Jie, Advisory Editor, Melin, Patricia, Advisory Editor, Nedjah, Nadia, Advisory Editor, Nguyen, Ngoc Thanh, Advisory Editor, Wang, Jun, Advisory Editor, Shakhovska, Natalya, editor, and Medykovskyy, Mykola O., editor
- Published
- 2020
- Full Text
- View/download PDF
11. The Influence of Entropy on the Classification Performance of a Non-linear Convolutional Neural Network
- Author
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Dzieciuch, Iryna, Gebhardt, Daniel, Abarbanel, Henry D. I., Series Editor, Braha, Dan, Series Editor, Érdi, Péter, Series Editor, Friston, Karl J., Series Editor, Haken, Hermann, Series Editor, Jirsa, Viktor, Series Editor, Kacprzyk, Janusz, Series Editor, Kaneko, Kunihiko, Series Editor, Kelso, Scott, Founding Editor, Kirkilionis, Markus, Series Editor, Kurths, Jürgen, Series Editor, Menezes, Ronaldo, Series Editor, Nowak, Andrzej, Series Editor, Qudrat-Ullah, Hassan, Series Editor, Reichl, Linda, Series Editor, Schuster, Peter, Series Editor, Schweitzer, Frank, Series Editor, Sornette, Didier, Series Editor, Thurner, Stefan, Series Editor, In, Visarath, editor, Longhini, Patrick, editor, and Palacios, Antonio, editor
- Published
- 2019
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12. Application of Qualitative Methods for the Investigation and Numerical Analysis of Some Dissipative Nonlinear Physical Systems
- Author
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Pukach, Petro, Il’kiv, Volodymyr, Nytrebych, Zinovii, Vovk, Myroslava, Pukach, Pavlo, Kacprzyk, Janusz, Series Editor, Pal, Nikhil R., Advisory Editor, Bello Perez, Rafael, Advisory Editor, Corchado, Emilio S., Advisory Editor, Hagras, Hani, Advisory Editor, Kóczy, László T., Advisory Editor, Kreinovich, Vladik, Advisory Editor, Lin, Chin-Teng, Advisory Editor, Lu, Jie, Advisory Editor, Melin, Patricia, Advisory Editor, Nedjah, Nadia, Advisory Editor, Nguyen, Ngoc Thanh, Advisory Editor, Wang, Jun, Advisory Editor, Shakhovska, Natalia, editor, and Medykovskyy, Mykola O., editor
- Published
- 2019
- Full Text
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13. Introduction: A Meta-theoretic Evaluation Framework for Kaiyu Studies
- Author
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Saito, Saburo, Higano, Yoshiro, Editor-in-Chief, Saito, Saburo, editor, and Yamashiro, Kosuke, editor
- Published
- 2018
- Full Text
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14. On the Asymptotic Methods of the Mathematical Models of Strongly Nonlinear Physical Systems
- Author
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Pukach, Petro, Il’kiv, Volodymyr, Nytrebych, Zinovii, Vovk, Myroslava, Pukach, Pavlo, Kacprzyk, Janusz, Series Editor, Pal, Nikhil R., Advisory Editor, Bello Perez, Rafael, Advisory Editor, Corchado, Emilio S., Advisory Editor, Hagras, Hani, Advisory Editor, Kóczy, László T., Advisory Editor, Kreinovich, Vladik, Advisory Editor, Lin, Chin-Teng, Advisory Editor, Lu, Jie, Advisory Editor, Melin, Patricia, Advisory Editor, Nedjah, Nadia, Advisory Editor, Nguyen, Ngoc Thanh, Advisory Editor, Wang, Jun, Advisory Editor, Shakhovska, Natalia, editor, and Stepashko, Volodymyr, editor
- Published
- 2018
- Full Text
- View/download PDF
15. Dynamics
- Author
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de Jesus, Vitor L. B., Ashby, Neil, Series editor, Brantley, William, Series editor, Deady, Matthew, Series editor, Fowler, Michael, Series editor, Hjorth-Jensen, Morten, Series editor, Inglis, Michael, Series editor, Klose, Heinz, Series editor, Sherif, Helmy, Series editor, and de Jesus, Vitor L. B.
- Published
- 2017
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16. Digital Twin: Mitigating Unpredictable, Undesirable Emergent Behavior in Complex Systems
- Author
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Grieves, Michael, Vickers, John, Kahlen, Franz-Josef, editor, Flumerfelt, Shannon, editor, and Alves, Anabela, editor
- Published
- 2017
- Full Text
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17. An intelligent sensing and detection system for accident preventions in four wheeler vehicles
- Author
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Sri Lakshmi Chandana, Pankaj Chawla, U.S.B.K. Mahalaxmi, Abhay Chaturvedi, D. Shamia, and V. Saritha
- Subjects
Record locking ,Computer science ,business.industry ,media_common.quotation_subject ,Automotive industry ,Physical system ,General Medicine ,Trouble shooting ,Fault (power engineering) ,Automotive engineering ,Door opening ,Electronics ,business ,Function (engineering) ,media_common - Abstract
The present automotive vehicles have almost 75 percentage of electronics part for many applications such as air bag system, door opening system, door lock systems. The proposed system focuses on measuring various physical system’s sensor readings and predicting other subsystem function by calibration. If any hardware system gets futile in the vehicle or if any dangerous gas is released or if engine temperature becomes high by load current, the fault can be identified. The sensor readings are uninterruptedly transmitted to the dash board part via the engine part core. In dash board, comparison of the threshold is done to identify sensor failures. The trouble shooting information to the user is displayed in the dash board. This proposed work will sustain a vehicle system to be in good working condition to overcome accidents.
- Published
- 2023
18. Fuzzy inferencing-based path planning with a cyber-physical framework and adaptive second-order SMC for routing and mobility control in a robotic network
- Author
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Anuj Nandanwar, Ranjith Ravindranathan Nair, and Laxmidhar Behera
- Subjects
lyapunov methods ,adaptive control ,mobile robots ,variable structure systems ,motion control ,control system synthesis ,path planning ,optimisation ,observers ,fuzzy control ,cyber-physical systems ,robust control ,optimal routing variables ,routing probability ,transmission rate ,discrete optimisation problem ,physical system ,relative motion control ,disturbance observer ,controller parameters ,adaptive tuning algorithm ,pioneer p3-dx robots ,cyber-physical framework ,mobility control ,robotic network ,fuzzy-based potential function ,optimal routing parameters ,adaptive second-order smc ,fuzzy inferencing-based path planning ,adaptive second-order sliding mode control scheme ,lyapunov theory ,robustness ,Cybernetics ,Q300-390 ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
In this study, the authors address the problem of optimal routing and relative motion control in a network of robots. The path planning scheme has been designed using a fuzzy-based potential function employing optimal routing parameters. The optimal routing variables, such as routing probability and the transmission rate are obtained using a discrete optimisation problem. To deal with the disturbances and uncertainties in the physical system, an adaptive second-order sliding mode control(SMC) scheme has been proposed for the relative motion control of the networks of robots, where the disturbances are estimated using a novel disturbance observer and the controller parameters are updated online using an adaptive tuning algorithm derived based on Lyapunov theory. The robustness of the proposed path planner and the control scheme are validated through simulation as well as through real-time experimentation based on Pioneer P3-DX robots. The comparison results based on conventional SMC and adaptive SMC are also drawn.
- Published
- 2020
- Full Text
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19. In What Sense Does the Brain Compute?
- Author
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Schweizer, Paul, Bueno, Otávio, Editor-in-chief, and Müller, Vincent C., editor
- Published
- 2016
- Full Text
- View/download PDF
20. The Descent of Math
- Author
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Walker, Sara Imari, Elitzur, Avshalom C., Series editor, Mersini-Houghton, Laura, Series editor, Padmanabhan, T., Series editor, Schlosshauer, Maximilian, Series editor, Silverman, Mark P., Series editor, Tuszynski, Jack A., Series editor, Vaas, Rüdiger, Series editor, Aguirre, Anthony, editor, Foster, Brendan, editor, and Merali, Zeeya, editor
- Published
- 2016
- Full Text
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21. A modeling approach supporting digital twin engineering : Optimizing the energy consumption of air conditioning facilities
- Author
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Nast, Benjamin, Reiz, Achim, Ivanovic, Nikola, Sandkuhl, Kurt, Nast, Benjamin, Reiz, Achim, Ivanovic, Nikola, and Sandkuhl, Kurt
- Abstract
Digital Twin (DT) is a concept that has become increasingly relevant in recent years. The basic idea is to connect (physical) facilities or devices with digital representations to monitor, manipulate and predict their behavior in real-time. This work presents a modeling approach supporting DT engineering for air conditioning facilities. We describe the architecture of our system for developing digital representations of physically existing facilities in an industrial use case. The paper focuses on (a) the developed modeling tool, (b) the cloud service configuration, and (c) data analysis that enables energy optimizations.
- Published
- 2023
- Full Text
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22. Transparent Digital Twin for Output Control Using Belief Rule Base
- Author
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Limao Zhang, Yu-Wang Chen, Chao Fu, and Leilei Chang
- Subjects
Optimization ,Standards ,Unification ,Computer science ,building tilt rate (BTR) ,Testing ,Control (management) ,0211 other engineering and technologies ,Physical system ,02 engineering and technology ,Control theory ,021105 building & construction ,0202 electrical engineering, electronic engineering, information engineering ,Analytical models ,Belief rule base (BRB) ,Electrical and Electronic Engineering ,output control ,Data models ,Uncertainty ,transparent digital twin (DT) ,Base (topology) ,Tunnel construction ,Digital twin ,Computer Science Applications ,Human-Computer Interaction ,Control and Systems Engineering ,Key (cryptography) ,020201 artificial intelligence & image processing ,Software ,Information Systems ,Metro system - Abstract
A transparent digital twin (DT) is designed for output control using the belief rule base (BRB), namely, DT-BRB. The goal of the transparent DT-BRB is not only to model the complex relationships between the system inputs and output but also to conduct output control by identifying and optimizing the key parameters in the model inputs. The proposed DT-BRB approach is composed of three major steps. First, BRB is adopted to model the relationships between the inputs and output of the physical system. Second, an analytical procedure is proposed to identify only the key parameters in the system inputs with the highest contribution to the output. Being consistent with the inferencing, integration, and unification procedures of BRB, there are also three parts in the contribution calculation in this step. Finally, the data-driven optimization is performed to control the system output. A practical case study on the Wuhan Metro System is conducted for reducing the building tilt rate (BTR) in tunnel construction. By comparing the results following different standards, the 80% contribution standard is proved to have the highest marginal contribution that identifies only 43.5% parameters as the key parameters but can reduce the BTR by 73.73%. Moreover, it is also observed that the proposed DT-BRB approach is so effective that iterative optimizations are not necessarily needed.
- Published
- 2022
23. Construction of a Digital Twin Framework Using Free and Open-Source Software Programs
- Author
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Vasanth Kumar T, S V Abhishek, T. V. Prabhakar, C R Sarweshkumar, and Karan Shah
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Software ,Computer Networks and Communications ,business.industry ,Computer science ,Physical system ,Process (computing) ,Open source software ,Software engineering ,business ,Process automation system - Abstract
We present a novel Digital Twin Framework for a portable table-top sized temperature-controlled system constructed entirely using free and open-source software programs. By utilizing tools such as Robotic Process Automation (RPA) and a PLC program, the entire process was automated to achieve a true Digital Twin. Further, a mathematical model was constructed for the temperature-controlled system. The data from the physical model and the mathematical model was then compared and a what-if scenario was analyzed to predict and prevent a potential failure in the physical system. Additionally, a simulation model was created to visualize the results.
- Published
- 2022
24. These from Bits
- Author
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Shikano, Yutaka, Elitzur, Avshalom C., Series editor, Mersini-Houghton, Laura, Series editor, Padmanabhan, T., Series editor, Schlosshauer, Maximilian, Series editor, Silverman, Mark P., Series editor, Tuszynski, Jack A., Series editor, Vaas, Rüdiger, Series editor, Aguirre, Anthony, editor, Foster, Brendan, editor, and Merali, Zeeya, editor
- Published
- 2015
- Full Text
- View/download PDF
25. Quantum Probability Theory and the Foundations of Quantum Mechanics
- Author
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Fröhlich, Jürg, Schubnel, Baptiste, Englert, Berthold-Georg, Series editor, Hänggi, Peter, Series editor, Jones, Richard A L, Series editor, von Löhneysen, H., Series editor, Raimond, Jean-Michel, Series editor, Theisen, Stefan, Series editor, Vollhardt, Dieter, Series editor, Rubio, Angel, Series editor, Hjorth-Jensen, Morten, Series editor, Wells, James D., Series editor, Lewenstein, Maciej, Series editor, Zank, Gary P, Series editor, Blanchard, Philippe, editor, and Fröhlich, Jürg, editor
- Published
- 2015
- Full Text
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26. Formulation and Simulation of the Sound Field in an Enclosure
- Author
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Ando, Yoichi, Wakayama, Masato, Editor-in-chief, Anderssen, Robert S., Series editor, Bauschke, Heinz H., Series editor, Broadbridge, Philip, Series editor, Cheng, Jin, Series editor, Chyba, Monique, Series editor, Cottet, Georges-Henri, Series editor, Cuminato, José Alberto, Series editor, Ei, Shin-ichiro, Series editor, Fukumoto, Yasuhide, Series editor, Hosking, Jonathan R. M., Series editor, Jofré, Alejandro, Series editor, Landman, Kerry, Series editor, McKibbin, Robert, Series editor, Mercer, Geoff, Series editor, Parmeggiani, Andrea, Series editor, Pipher, Jill, Series editor, Polthier, Konrad, Series editor, Schilders, Wil, Series editor, Shen, Zuowei, Series editor, Toh, Kim-Chuan, Series editor, Verbitskiy, Evgeny, Series editor, Yoshida, Nakahiro, Series editor, and Ando, Yoichi
- Published
- 2015
- Full Text
- View/download PDF
27. Adaptive Fuzzy SOSM Controller Design With Output Constraints
- Author
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Keqi Mei, Ju H. Park, Shihong Ding, and Binbin Zhang
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Constraint (information theory) ,Nonlinear system ,Computational Theory and Mathematics ,Artificial Intelligence ,Control and Systems Engineering ,Control theory ,Computer science ,Applied Mathematics ,Integrator ,Physical system ,Stability (learning theory) ,Fuzzy control system ,Fuzzy logic - Abstract
The output constraints are widespread in physical systems. Violation of output constraints may result in system damage and performance degradation. This paper investigates the design issue of adaptive fuzzy second-order sliding mode (SOSM) controller, which aims to handle a class of nonlinear systems with output constraints. The unknown bounds of uncertainties are approached dynamically by fuzzy logic systems. Through designing a new barrier Lyapunov function, the output constraint problem has been well solved. Then, by integrating adding a power integrator (API) technology and adaptive fuzzy control, a novel adaptive fuzzy SOSM controller is proposed. It is proved that the proposed method makes the output variable not violate the specified constraint region. At the same time, it can be shown based upon the Lyapunov approach that the finite-time stability of the resulting closed-loop system under output constraint is ensured. Finally, a numerical example and a practical pendulum system are presented to demonstrate the validity of the proposed SOSM control strategy.
- Published
- 2022
28. High-Performance Reservoir Computing With Fluctuations in Linear Networks
- Author
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Miguel C. Soriano, Johannes Nokkala, Rodrigo Martínez-Peña, and Roberta Zambrini
- Subjects
Computer Networks and Communications ,Computer science ,Linear system ,MathematicsofComputing_NUMERICALANALYSIS ,Physical system ,Reservoir computing ,Topology ,Computer Science Applications ,Nonlinear system ,Noise ,Artificial Intelligence ,Robustness (computer science) ,Benchmark (computing) ,Echo state network ,Software - Abstract
Reservoir computing has emerged as a powerful machine learning paradigm for harvesting nontrivial information processing out of disordered physical systems driven by sequential inputs. To this end, the system observables must become nonlinear functions of the input history. We show that encoding the input to quantum or classical fluctuations of a network of interacting harmonic oscillators can lead to a high performance comparable to that of a standard echo state network in several nonlinear benchmark tasks. This equivalence in performance holds even with a linear Hamiltonian and a readout linear in the system observables. Furthermore, we find that the performance of the network of harmonic oscillators in nonlinear tasks is robust to errors both in input and reservoir observables caused by external noise. For any reservoir computing system with a linear readout, the magnitude of trained weights can either amplify or suppress noise added to reservoir observables. We use this general result to explain why the oscillators are robust to noise and why having precise control over reservoir memory is important for noise robustness in general. Our results pave the way toward reservoir computing harnessing fluctuations in disordered linear systems.
- Published
- 2022
29. Real-Time and Adaptive Reservoir Computing With Application to Profile Prediction in Fusion Plasma
- Author
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Joseph Abbate, Egemen Kolemen, Geert Verdoolaege, Azarakhsh Jalalvand, and Rory Conlin
- Subjects
Fusion ,Tokamak ,Computer Networks and Communications ,Computer science ,Physical system ,Reservoir computing ,Plasma ,Convolutional neural network ,Computer Science Applications ,Computational science ,law.invention ,Artificial Intelligence ,law ,Nuclear fusion ,Adaptation (computer science) ,Software - Abstract
Nuclear fusion is a promising alternative to address the problem of sustainable energy production. The tokamak is an approach to fusion based on magnetic plasma confinement, constituting a complex physical system with many control challenges. We study the characteristics and optimization of reservoir computing (RC) for real-time and adaptive prediction of plasma profiles in the DIII-D tokamak. Our experiments demonstrate that RC achieves comparable results to state-of-the-art (deep) convolutional neural networks (CNNs) and long short-term memory (LSTM) models, with a significantly easier and faster training procedure. This efficient approach allows for fast and frequent adaptation of the model to new situations, such as changing plasma conditions or different fusion devices.
- Published
- 2022
30. Engineering the sensitivity of macroscopic physical systems to variations in the fine-structure constant
- Author
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M. Bober, Michal Zawada, Daniel Lisak, Piotr Wcisło, Beata Zjawin, and Roman Ciuryło
- Subjects
High Energy Astrophysical Phenomena (astro-ph.HE) ,High Energy Physics - Phenomenology ,High Energy Physics - Phenomenology (hep-ph) ,Materials science ,Atomic Physics (physics.atom-ph) ,Physical system ,FOS: Physical sciences ,General Physics and Astronomy ,Fine-structure constant ,Sensitivity (control systems) ,Biological system ,Astrophysics - High Energy Astrophysical Phenomena ,Physics - Atomic Physics - Abstract
Experiments aimed at searching for variations in the fine-structure constant α are based on spectroscopy of transitions in microscopic bound systems, such as atoms and ions, or resonances in optical cavities. The sensitivities of these systems to variations in α are typically on the order of unity and are fixed for a given system. For heavy atoms, highly charged ions and nuclear transitions, the sensitivity can be increased by benefiting from the relativistic effects and favorable arrangement of quantum states. This article proposes a new method for controlling the sensitivity factor of macroscopic physical systems. Specific concepts of optical cavities with tunable sensitivity to α are described. These systems show qualitatively different properties from those of previous studies of the sensitivity of macroscopic systems to variations in α, in which the sensitivity was found to be fixed and fundamentally limited to an order of unity. Although possible experimental constraints attainable with the specific optical cavity arrangements proposed in this article do not yet exceed the present best constraints on α variations, this work paves the way for developing new approaches to searching for variations in the fundamental constants of physics.
- Published
- 2023
31. Distinctive Features and Underlying Rationale of a Philosophically-Informed Approach for Energy Teaching
- Author
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Papadouris, Nicos, Constantinou, Constantinos P., Chen, Robert F., editor, Eisenkraft, Arthur, editor, Fortus, David, editor, Krajcik, Joseph, editor, Neumann, Knut, editor, Nordine, Jeffrey, editor, and Scheff, Allison, editor
- Published
- 2014
- Full Text
- View/download PDF
32. ABATe: Automatic Behavioral Abstraction Technique to Detect Anomalies in Smart Cyber-Physical Systems
- Author
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Sandeep Narayanan, Ranjan Bose, and Anupam Joshi
- Subjects
Artificial neural network ,Computer science ,Event (computing) ,media_common.quotation_subject ,Physical system ,computer.software_genre ,Semantics ,Adaptability ,Domain (software engineering) ,Data mining ,False positive rate ,Electrical and Electronic Engineering ,computer ,Abstraction (linguistics) ,media_common - Abstract
Detecting anomalies and attacks in smart cyber-physical systems are of paramount importance owing to their growing prominence in controlling critical systems. However, this is a challenging task due to the heterogeneity and variety of components of a CPS, and the complex relationships between sensed values and potential attacks or anomalies. Such complex relationships are results of physical constraints and domain norms which exist in many CPS domains. In this paper, we propose ABATe, an Automatic Behavioral Abstraction Technique based on Neural Networks for detecting anomalies in smart cyber-physical systems. Unlike traditional techniques which abstract the statistical properties of different sensor values, ABATe learns complex relationships between event vectors from normal operational data available in abundance with smart CPS and uses this abstracted model to detect anomalies. ABATe detected more than 88% of attacks in the publicly available SWaT dataset featuring data from a scaled down Sewage Water Treatment plant with a very low false positive rate of 1%. We also evaluated our technique's ability to capture domain semantics and multi-domain adaptability using a real-world automotive dataset, as well as a synthetic dataset.
- Published
- 2022
33. Symmetry analysis, closed-form invariant solutions and dynamical wave structures of the generalized (3+1)-dimensional breaking soliton equation using optimal system of Lie subalgebra
- Author
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Monika Niwas, Harsha Kharbanda, and Sachin Kumar
- Subjects
Physics ,Nonlinear system ,Environmental Engineering ,Classical mechanics ,One-dimensional space ,Physical system ,Trigonometric functions ,Ocean Engineering ,Vector field ,Soliton ,Invariant (physics) ,Oceanography ,Symmetry (physics) - Abstract
Nonlinear evolution equations (NLEEs) are primarily relevant to nonlinear complex physical systems in a wide range of fields, including ocean physics, plasma physics, chemical physics, optical fibers, fluid dynamics, biology physics, solid-state physics, and marine engineering. This paper investigates the Lie symmetry analysis of a generalized (3+1)-dimensional breaking soliton equation depending on five nonzero real parameters. We derive the Lie infinitesimal generators, one-dimensional optimal system, and geometric vector fields via the Lie symmetry technique. First, using the three stages of symmetry reductions, we converted the generalized breaking soliton (GBS) equation into various nonlinear ordinary differential equations (NLODEs), which have the advantage of yielding a large number of exact closed-form solutions. All established closed-form wave solutions include special functional parameter solutions, as well as hyperbolic trigonometric function solutions, trigonometric function solutions, dark-bright solitons, bell-shaped profiles, periodic oscillating wave profiles, combo solitons, singular solitons, wave-wave interaction profiles, and various dynamical wave structures, which we present for the first time in this research. Eventually, the dynamical analysis of some established solutions is revealed through three-dimensional sketches via numerical simulations. Some of the new solutions are often useful and helpful for studying the nonlinear wave propagation and wave-wave interactions of shallow water waves in many new high-dimensional nonlinear evolution equations.
- Published
- 2022
34. Robust Cooperative Control of Isolated AC Microgrids Subject to Unreliable Communications: A Low-Gain Feedback Approach
- Author
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Mehdi Karrari, Josep M. Guerrero, Hamid Reza Baghaee, Gevork B. Gharehpetian, and Amir Afshari
- Subjects
Computer Networks and Communications ,Computer science ,Physical system ,static nonlinearities ,Topology ,voltage regulation ,Heuristic algorithms ,jointly connected topology ,Microgrids ,Electrical and Electronic Engineering ,Robustness ,MATLAB ,parametric uncertainties ,computer.programming_language ,Multi-agent system ,Uncertainty ,Control engineering ,AC power ,Telecommunications network ,Computer Science Applications ,Nonlinear system ,Frequency regulation ,Control and Systems Engineering ,Voltage control ,Control system ,Microgrid ,Switches ,computer ,robust control ,Information Systems - Abstract
Inherent nonlinearities and uncertainties are inseparable parts of the real-life engineering systems, which make theoretical analyzes and control system designs more challenging. Usually, most of the physical parts in control systems such as controllers and actuators are subjected to saturation. On the other hand, uncertainties are ubiquitous in the physical systems, which demand some necessities in the design of the control system. Additionally, unreliability in communication networks is another practical constraint in multiagent systems, which is required to be considered. In this article, based on the mentioned issues, a distributed robust algorithm is proposed for the semiglobal stabilization of the voltage and frequency of isolated (islanded) ac microgrids considering parameters uncertainties, static nonlinearity of actuators, and unreliability in the communication network. In this regard, by employing an adaptive low-gain feedback protocol, the robust performance of the closed-loop system is guaranteed. Finally, to evaluate the proposed control strategy’s performance, digital time-domain simulations are carried out on a test microgrid system in MATLAB/Simulink environment, and the results are compared with several previously reported methods. Simulation results and comparison with previous works reveal the proposed method’s effectiveness and accuracy in regulating the microgrid voltage/frequency and providing accurate proportional active power sharing.
- Published
- 2022
35. Land-sea relay fishery networked microgrids under the background of cyber-physical fusion: Characteristics and key issues prospect
- Author
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Ruosi Zhang, Xi Chen, and Yuntao Ju
- Subjects
Mainland China ,business.industry ,Computer science ,020209 energy ,010401 analytical chemistry ,Control (management) ,Cyber-physical system ,Physical system ,Submarine ,Forestry ,02 engineering and technology ,Aquatic Science ,01 natural sciences ,0104 chemical sciences ,Computer Science Applications ,Renewable energy ,law.invention ,Fishery ,Relay ,law ,0202 electrical engineering, electronic engineering, information engineering ,Key (cryptography) ,Animal Science and Zoology ,business ,Agronomy and Crop Science - Abstract
The locations of marine ranch and its surrounding islands are far away from the mainland, so the cost is too high to keep power supply by laying submarine cables from the mainland. Therefore, it is necessary to build a land-sea relay networked microgrids with high proportion of renewable energy, which is able to provide multi-energy complementary and reliable power for marine ranch and its surrounding islands. It is noteworthy that the networked microgrids is a typical cyber-physical system. In order to deeply reveal the cyber physical fusion characteristics of fishery networked microgrids, the morphology and key techniques of fishery networked microgrids are summarized from two aspects: physical system and cyber system. And the interactions of cyber and physical system are described, including the support from cyber system for the physical system as state perception and control, and the power support from physical system for cyber system. Based on the above interactions, the related research on coupling analysis of cyber-physical system is summarized. Finally, some urgently studied problems have been looked forward to in fishery networked microgrids cyber-physical system.
- Published
- 2022
36. Exact travelling wave solutions for nonlinear system of spatiotemporal fractional quantum mechanics equations
- Author
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Mohammed Alabedalhadi
- Subjects
Physics ,Partial differential equation ,Riemann–Liouville derivative ,General Engineering ,Physical system ,Nonlinear optics ,Traveling wave method ,Engineering (General). Civil engineering (General) ,Quantum mechanics ,Fractional calculus ,Schrödinger equation ,Nonlinear system ,symbols.namesake ,symbols ,Applied mathematics ,Bäcklund transformation ,TA1-2040 ,Fractional Schrödinger equation ,Fractional quantum mechanics ,Harmonic oscillator - Abstract
Schrodinger equation is an indispensable model for quantum mechanics, used for modelling several fascinating complex nonlinear physical systems, such as quantum condensates, nonlinear optics, hydrodynamics, shallow-water waves, and the harmonic oscillator. The objective of this paper is to investigate and study the exact travelling wave solutions of nonlinear triple fractional Schrodinger equations involving a modified Riemann–Liouville fractional derivative. Using the Riccati-Bernoulli Sub-ODE technique, the Backlund transformation is employed to handle the posed system. The traveling wave solutions methodology lies in converting the fractional Schrodinger equations into a nonlinear system of fractional ODEs. An infinite sequence of solutions to the fractional partial differential equations can be obtained directly through solving the resulting nonlinear fractional system. Some graphical representations of the obtained solutions after selecting suitable values for fractional values and parameters are illustrated to test accuracy and verify the power, and effectiveness of the proposed method.
- Published
- 2022
37. Matrix transfer technique for anomalous diffusion equation involving fractional Laplacian
- Author
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Vo Anh, Zhengmeng Jin, Fawang Liu, and Minling Zheng
- Subjects
Numerical Analysis ,Discretization ,Anomalous diffusion ,Applied Mathematics ,Physical system ,010103 numerical & computational mathematics ,Operator theory ,01 natural sciences ,Stability (probability) ,010101 applied mathematics ,Computational Mathematics ,Matrix (mathematics) ,Lévy flight ,Convergence (routing) ,Applied mathematics ,0101 mathematics ,Mathematics - Abstract
The fractional Laplacian, ( − △ ) s , s ∈ ( 0 , 1 ) , appears in a wide range of physical systems, including Levy flights, some stochastic interfaces, and theoretical physics in connection to the problem of stability of the matter. In this paper, a matrix transfer technique (MTT) is employed combining with spectral/element method to solve fractional diffusion equations involving the fractional Laplacian. The convergence of the MTT method is analyzed by the abstract operator theory. Our method can be applied to solve various fractional equation involving fractional Laplacian on some complex domains. Numerical results indicate exponential convergence in the spatial discretization which is in good agreement with the theoretical analysis.
- Published
- 2022
38. Transformers for modeling physical systems
- Author
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Nicholas Geneva and Nicholas Zabaras
- Subjects
FOS: Computer and information sciences ,Computer Science - Machine Learning ,Dynamical systems theory ,Cognitive Neuroscience ,Physical system ,FOS: Physical sciences ,010103 numerical & computational mathematics ,Dynamical system ,Machine learning ,computer.software_genre ,01 natural sciences ,Field (computer science) ,Machine Learning (cs.LG) ,010305 fluids & plasmas ,Machine Learning ,Artificial Intelligence ,Physical phenomena ,0103 physical sciences ,0101 mathematics ,Representation (mathematics) ,Language ,Natural Language Processing ,Transformer (machine learning model) ,business.industry ,Deep learning ,Computational Physics (physics.comp-ph) ,Artificial intelligence ,business ,Physics - Computational Physics ,computer - Abstract
Transformers are widely used in natural language processing due to their ability to model longer-term dependencies in text. Although these models achieve state-of-the-art performance for many language related tasks, their applicability outside of the natural language processing field has been minimal. In this work, we propose the use of transformer models for the prediction of dynamical systems representative of physical phenomena. The use of Koopman based embeddings provide a unique and powerful method for projecting any dynamical system into a vector representation which can then be predicted by a transformer. The proposed model is able to accurately predict various dynamical systems and outperform classical methods that are commonly used in the scientific machine learning literature., 22 pages, 14 figures, 3 appendices
- Published
- 2022
39. A Multi-Simplex Imperialist Competitive Paradigm for Solving Nonlinear Physical Systems
- Author
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Salem Alkhalaf, Shaukat Iqbal, and Javaid Ali
- Subjects
Nonlinear system ,Mathematical optimization ,Simplex ,Computational Theory and Mathematics ,Artificial Intelligence ,Computer science ,Physical system ,Software ,Theoretical Computer Science - Published
- 2022
40. FEEDBACK CONTROL FOR RANDOM, LINEAR HYPERBOLIC BALANCE LAWS
- Author
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Muhammad Imran, Markus Bambach, Michael Herty, and Stephan Gerster
- Subjects
Statistics and Probability ,Lyapunov stability ,Balance (metaphysics) ,Control and Optimization ,Viscoplasticity ,Computer science ,Control (management) ,MathematicsofComputing_NUMERICALANALYSIS ,Physical system ,State (functional analysis) ,System dynamics ,Optimization and Control (math.OC) ,Modeling and Simulation ,Law ,FOS: Mathematics ,Discrete Mathematics and Combinatorics ,Series expansion ,Mathematics - Optimization and Control - Abstract
We design the controls of physical systems that are faced by uncertainties. The system dynamics are described by random hyperbolic balance laws. The control aims to steer the system to a desired state under uncertainties. We propose a control based on Lyapunov stability analysis of a suitable series expansion of the random dynamics. The control damps the impact of uncertainties exponentially fast in time. The presented approach can be applied to a large class of physical systems and random perturbations, as e.g. Gaussian processes. We illustrate the control effect on a stochastic viscoplastic material model.
- Published
- 2022
41. Distributed Vehicle to Grid Integration Over Communication and Physical Networks With Uncertainty Effects
- Author
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Rahmat Poudineh, Anupama Sen, and Dimitra Apostolopoulou
- Subjects
State of charge ,business.product_category ,General Computer Science ,Operations research ,Computer science ,Market clearing ,Electric vehicle ,Physical system ,Vehicle-to-grid ,Constraint satisfaction ,business ,Grid ,Telecommunications network - Abstract
This paper proposes a distributed framework for vehicle grid integration taking into account the communication and physical networks. To this end, we model the electric vehicle behaviour that includes times of departure and arrival, state of charge, required energy, and its objectives, e.g., avoid battery degradation and willingness to pay. Next, we formulate the centralised day ahead distribution market which explicitly represents the physical system, supports unbalanced three phase networks with delta and wye connections, and incorporates the charging needs of electric vehicles under a uni-and a bi-directional charging scheme. The solution of the centralised market requires knowledge of electric vehicle information in terms of desired energy, departure and arrival times that electric vehicle owners are reluctant in providing. Moreover, the computational effort required to solve the day ahead distribution market in cases of numerous electric vehicles is very intensive. As such, we propose a distributed solution of the day ahead distribution market clearing mechanism over a time-varying communication network where no private information is exchanged. We also incorporate uncertainty of electric vehicle charging needs and provide guarantees on the probability of constraint satisfaction. We illustrate the proposed vehicle grid integration framework through the 13-bus, 33-bus, and 141-bus distribution feeders.
- Published
- 2022
42. Barriers in designing and developing products by additive manufacturing for bio-mechanics systems in healthcare sector
- Author
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Rajender Kumar, Pankaj Shakkarwal, Punj Lata Singh, and Vishal Tyagi
- Subjects
Risk analysis (engineering) ,Manufacturing process ,business.industry ,Computer science ,media_common.quotation_subject ,Health care ,Exaggeration ,Physical system ,business ,Affect (psychology) ,Bio mechanics ,media_common - Abstract
Aspirations among human beings for living a long life with joy and comfort are escalating the demand for advanced technologies. Humans having any physical disorders wish to live a healthier life through the artificial organ transplant-ship. Here it is noteworthy that the replaced organ should behave like the original one otherwise it may affect the other organs too. It is an exaggeration to say that the usage of the computational approach in getting the solutions for real-life problems is not new. Still, the contribution of the utility of computational approaches in Bio-systems is not at par. The reason is one can’t provide multiple inputs especially in the physical systems in the industry. This leads to creating gaps in the inputs to the tools about detailed knowledge of the bio-systems. The present study reports barriers associated with the utility of the additive manufacturing process for developing the products of Bio-systems.
- Published
- 2022
43. Collisions-Free Distributed Optimal Coordination for Multiple Euler-Lagrangian Systems
- Author
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Guang-Hong Yang and Liwei An
- Subjects
Lyapunov function ,Mathematical optimization ,Computer science ,Physical system ,Nonlinear control ,Computer Science Applications ,symbols.namesake ,Control and Systems Engineering ,Convergence (routing) ,Convex optimization ,symbols ,Electrical and Electronic Engineering ,Protocol (object-oriented programming) ,Collision avoidance ,Parametric statistics - Abstract
Multi-agent distributed optimal coordination (DOC) involves the motion conflicts of large numbers of physical systems, which leads to significant safety challenges in terms of collision avoidance. This paper studies the problem of secure DOC for multiple uncertain Euler-Lagrangian (EL) systems. The objective is to steer each EL agent to achieve the optimization task while avoiding collisions with other agents. The main challenge focuses on the co-design of optimal coordination strategy and collision avoidance mechanism. The safety barrier certificates in the closed form of path integrals are constructed which generate provably collisions-free behaviors. With convex optimization and adaptive nonlinear control, a fully distributed protocol is proposed. Based on Lyapunov method and boundedness analysis for the barrier functions, it is proved that the protocol simultaneously guarantees the global convergence and collision avoidance of the EL systems in the presence of parametric uncertainties.
- Published
- 2022
44. Towards improved understanding of the hydrodynamics of a semi-partition bioreactor (SPB): A numerical investigation
- Author
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Robert W.M. Pott, George Mbella Teke, and Godfrey Kabungo Gakingo
- Subjects
business.industry ,Computer science ,General Chemical Engineering ,Volumetric flux ,Mixing (process engineering) ,Physical system ,Flux ,General Chemistry ,Computational fluid dynamics ,Unit operation ,Bioreactor ,Extraction (military) ,business ,Process engineering - Abstract
Extractive fermentation is a technology used to combat product inhibition. However, there has been comparatively low adoption of this technique in industry and this can be attributed to, among other reasons, a need for novel and optimised bioreactor configurations to facilitate this unit operation. Recent research has proposed a novel Semi-Partition Bioreactor (SPB) which combines the fermentation (mixer section) and extraction (settler section) steps in one reactor thus simplifying the operation of extractive fermentation. However, while the bioreactor was shown to be feasible, an improved understanding of the reactor’s hydrodynamics is required to allow for optimised designs. This study thus focuses on the use of validated Computational Fluid Dynamics (CFD) simulations to investigate the hydrodynamics of the SPB. Key findings illustrate that, unsurprisingly, normal stirred tank reactors’ hydrodynamics are significantly changed by the introduction of a settler. Consequently, the modified hydrodynamics influence the volumetric flux between the fermentation and extraction sections. Accurate modelling of this flux gives insights into various operational choices and physical systems (for instance modifying the settler insert). Key then is accurately matching the CFD model with experimental work. For example, it has been shown that mixing time (in the settler) can be predicted to within 14.8% accuracy if the transient nature of the volumetric flux is considered as opposed to a 57% accuracy if a constant flux is assumed. Finally, a design approach for the in silico prediction of possible volumetric removal rates of top phase from the settler has been proposed. This approach would be of interest to a bioreactor engineer seeking to, for example, estimate an optimal removal rate that prevents over-accumulation of a toxic species and subsequent product inhibition.
- Published
- 2022
45. Electrons with Spin
- Author
-
Pieter Kok
- Subjects
Physics ,Property (philosophy) ,Simple (abstract algebra) ,Quantum mechanics ,Physical system ,Observable ,Electron ,Spin-½ - Abstract
In this chapter, we describe a simple experiment about the spin property of an electron and use it to determine what is a physical observable in quantum mechanics. We give a general description of physical systems with two distinct states. We conclude this chapter with a brief description how spin can be used in magnetic resonance imaging, a technique that is used in hospitals to reveal what is going on inside your brain.
- Published
- 2023
46. Energy-Based Modeling of Ionic Polymer–Metal Composite Actuators Dedicated to the Control of Flexible Structures
- Author
-
Yongxin Wu, Yann Le Gorrec, and Ning Liu
- Subjects
Coupling ,Work (thermodynamics) ,Discretization ,Computer science ,Finite difference method ,Physical system ,Topology ,Computer Science Applications ,Hamiltonian system ,symbols.namesake ,Control and Systems Engineering ,Lagrange multiplier ,symbols ,Electrical and Electronic Engineering ,Actuator - Abstract
This paper deals with the control-oriented energy-based modeling of ionic polymer metal composite patches using multiscale infinite dimensional port-Hamiltonian formulations and Lagrange multipliers. Inspired by the work of Gou Nishida et al. 2012, but considering different assumptions, this paper focuses on the constraints arising from the coupling between the polymer gel and the compliant mechanical structure of the actuator, under the quasi-static mechanical assumption for the gel, leading to a constrained port Hamiltonian system. The geometric structure of the overall system and the associated energy balance are derived. The proposed energy-based model of the IPMC actuator allows deriving controllers via energy-based control design methods with a clear physical interpretation. The proposed actuator model is further discretized in space using a structure preserving finite difference method. The Lagrange multipliers are eliminated using coordinate projections. Simulations are compared with experimental results. With proper discretization numbers, our model is consistent with the physical system. Finally, Lagrange multipliers are exploited to connect the actuator to a 2-dimensional flexible structure stemming from the modeling of a flexible endoscope.
- Published
- 2021
47. Interface Algorithm Design for Power Hardware-in-the-loop Emulation of Modular Multilevel Converter Within High-Voltage Direct Current Systems
- Author
-
Zigao Xu, Dianguo Xu, Binbin Li, Linjie Han, and Shengbo Wang
- Subjects
Computer science ,business.industry ,Interface (computing) ,Hardware-in-the-loop simulation ,Physical system ,Modular design ,Control and Systems Engineering ,Electronic engineering ,RLC circuit ,Algorithm design ,High-voltage direct current ,Electrical and Electronic Engineering ,business ,Electrical impedance - Abstract
Power hardware-in-the-loop (PHIL) simulation combines the advantages of digital simulation and physical experiment, which provides great convenience for research and verification of a complex electric system, such as the high-voltage direct current (HVdc) system. The digital interface algorithm realizes interconnection of the digital and physical system, but it is also the main factor to affect stability and accuracy of the PHIL results. In this article, the damping impedance interface algorithm is adopted to test the performance of a modular multilevel converter (MMC) connected into an HVdc system. Instead of online acquiring the exact MMC dc impedance, a simple RLC damping impedance is proposed to ensure stability and particularly, low-frequency accuracy for the PHIL system. Moreover, as testing in the laboratory does not allow hundreds of MVA-rated physical MMC, suitable scaling factors are proposed to design a scaled-down MMC prototype which presents identical dynamic characteristic with a full-scale MMC. A PHIL setup including RT-LAB real-time simulator, power amplifier, and a scaled-down MMC prototype is built and the experiments confirm the effectiveness of the proposed interface algorithm.
- Published
- 2021
48. Against Computational Perspectivalism
- Author
-
Dimitri Coelho Mollo
- Subjects
Cognitive science ,History ,Computer science ,Computation ,Physical computation ,05 social sciences ,Physical system ,Collapse (topology) ,06 humanities and the arts ,050905 science studies ,0603 philosophy, ethics and religion ,Philosophy ,History and Philosophy of Science ,Teleology ,060302 philosophy ,Mainstream ,0509 other social sciences - Abstract
Computational perspectivalism has been recently proposed as an alternative to mainstream accounts of physical computation, and especially to the teleologically-based mechanistic view. It takes physical computation to be partly dependent on explanatory perspectives, and eschews appeal to teleology in helping individuate computational systems. I assess several varieties of computational perspectivalism, showing that they either collapse into existing non-perspectival views; or end up with unsatisfactory or implausible accounts of physical computation. Computational perspectivalism fails therefore to be a compelling alternative to perspective-independent theories of computation in physical systems. I conclude that a teleologically-based, non-perspectival mechanistic account of physical computation is to be preferred.
- Published
- 2021
49. Self-regulation in chemical and bio-engineering materials for intelligent systems
- Author
-
Zhongyuan Huang, Kewei Lei, Dan He, Yanbin Xu, Jacob Williams, Liu Hu, Macy McNeil, Juan M. Ruso, Zhen Liu, Zhanhu Guo, and Zhe Wang
- Subjects
nanostructured materials ,fracture ,valence bands ,composite materials ,intelligent materials ,porous materials ,biomedical materials ,physical system ,self-regulatory materials ,bio-engineering materials ,intelligent systems ,self-regulation system ,biomedical system ,mechanical structure ,external perturbation ,oil-water interface ,cell out-layer structure ,radical activity ,electron energy level ,Computational linguistics. Natural language processing ,P98-98.5 ,Computer software ,QA76.75-76.765 - Abstract
Herein, the authors review the self-regulation system secured by well-designed hybrid materials, composites, and complex system. As a broad concept, the self-regulated material/system has been defined in a wide research field and proven to be of great interest for use in a biomedical system, mechanical system, physical system, as the fact of something such as an organisation regulating itself without intervention from external perturbation. Here, they focus on the most recent discoveries of self-regulation phenomenon and progress in utilising the self-regulation design. This paper concludes by examining various practical applications of the remarkable materials and systems including manipulation of the oil/water interface, cell out-layer structure, radical activity, electron energy level, and mechanical structure of nanomaterials. From material science to bioengineering, self-regulation proves to be not only viable, but increasingly useful in many applications. As part of intelligent engineering, self-regulatory materials are expected to be more used as integrated intelligent components.
- Published
- 2018
- Full Text
- View/download PDF
50. Reform of power system governance in the context of system change
- Author
-
Andrew C. Wright
- Subjects
environmental factors ,government policies ,power markets ,power system governance ,system change ,governance arrangements ,environmental constraints ,regulatory framework ,commercial framework ,institutional framework ,rapid change ,substantial change ,flexible thermal power stations ,integrated smart system ,physical system ,social constraints ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
Regulatory, commercial and governance arrangements form an integral part of any power system. They ensure that the underlying physical system fulfils the critical public function of electricity supply within agreed social and environmental constraints. If either the physical system or societal expectations change, the regulatory, commercial and institutional framework will need to adapt in response. This is necessary to ensure continued good outcomes for consumers at a reasonable cost. Power systems in many countries are going through rapid and substantial change, as a result of the twin pressures of decarbonisation and technological innovation. The power system is moving from one dominated by large-scale, transmission-connected, flexible thermal power stations serving passive demand, to an integrated smart system connecting increasingly distributed and intermittent energy resources integrated with an active demand side. As a result, there is a need for far-reaching reforms of institutions, charging arrangements, market structures and regulations. Fundamental notions, such as security of supply and the universal service obligation need to be revisited. This is a challenge for policy makers and regulators wherever these changes are taking place.
- Published
- 2018
- Full Text
- View/download PDF
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