Dissipative Control Research Articles

Design of Event-Triggered Finite-Time Dissipative Control for Fractional-Order Time-Delay Interconnected Systems

Design of Event-Triggered Finite-Time Dissipative Control for Fractional-Order Time-Delay Interconnected Systems

Event-Triggered Asynchronous Dissipative Control for Markov Jump Systems With Unknown Probabilities

Event-Triggered Asynchronous Dissipative Control for Markov Jump Systems With Unknown Probabilities

Characteristics of low-temperature oxidative heating and gas production in coal storage under forced convection: Influencing factors and mechanisms.

Slow oxidation of coal during storage and transportation poses significant risks, making it essential to identify hot spots and understand the heat generation and gas production patterns in coal stockpiles. This study leverages the advantages of adiabatic oxidation experiments, which account for time effects, to accurately describe the low-temperature oxidation process of coal through warming and gas production dimensions. Additionally, the warming and gas production patterns of three-dimensional coal stockpiles with varying stacking parameters were investigated. The results indicate that activation energy for heat generation increases linearly with particle size. In anthracite and bituminous coals, the activation energy for gas production was lower than that for heat generation below 70°C, but higher above 70°C. Lignite showed a general trend of lower activation energy for heat generation compared to gas production. Under forced convection, airflow paths within the three-dimension coal stockpile became more complex, resulting in 3 distinct flow patterns. As external wind speed increased, the dominant factor in coal oxidation shifted from oxygen concentration control to heat dissipation control. Maintaining porosity below 0.15, particle size under 5mm, height under 8m, and slope angle below 40° can effectively delay the oxidation process. The factors influencing coal storage efficiency, ranked by importance, are wind speed, porosity, geometry, and particle size. This study offers theoretical insights for optimizing coal storage and transportation processes.

Novel Implicit Integration Algorithms With Identical Second‐Order Accuracy and Flexible Dissipation Control for First‐Order Transient Problems

ABSTRACTFor the solutions of first‐order transient problems with optimal efficiency, conventional single‐step implicit methodologies, unaided by additional post‐processing techniques, encounter limitations in concurrently attaining identical second‐order accuracy and controllable numerical dissipation. Addressing this challenge, the present study contributes not only a comprehensive analytical framework for formulating implicit integration algorithms but also leverages the auxiliary variable and the composite sub‐step technique to propose two distinct types of implicit integration algorithms. Each type is characterized by self‐initiation, unconditional stability, identical second‐order accuracy, controllable numerical dissipation, and zero‐order overshoots. Recognizing that single‐step implicit methods can be conceptualized as composite single‐sub‐step ones, both algorithm types achieve identical effective stiffness matrices, thereby reducing the computational effort for solving linear problems. The utilization of auxiliary variables endows the proposed single‐step method with numerical attributes akin to established counterparts, while achieving identical second‐order accuracy. Conversely, the adoption of the composite sub‐step technique in the proposed two‐sub‐step methods surpasses the published algorithms by significantly reducing the error constants. This superiority persists when enforcing the same sub‐step sizes and sub‐step dissipation levels. Numerical simulations affirm that the proposed methods consistently outperform existing alternatives without incurring additional computational expenses.

Event‐Triggered Dissipative Control of Discrete‐Time 2‐D Switched Systems With Mixed Delays

Event‐Triggered Dissipative Control of Discrete‐Time 2‐D Switched Systems With Mixed Delays

Robust Dissipative Control and Filtering for 2-D Discrete-Time Switched Systems with Time-Varying Delays

Robust Dissipative Control and Filtering for 2-D Discrete-Time Switched Systems with Time-Varying Delays

Temporal periodic solutions of non-isentropic compressible Euler equations with geometric effects

Abstract In this article, we investigate the general qusi-one-dimensional nozzle flows governed by non-isentropic compressible Euler system. First, the steady states of the subsonic and supersonic flows are analyzed. Then, the existence, stability, and uniqueness of the subsonic temporal periodic solutions around the steady states are proved by constructing a new iterative format technically. Besides, further regularity and stability of the obtained temporal periodic solutions are obtained, too. The main difficulty in the proof is coming from derivative loss, which is caused by the diagonalization. Observing that the entropy is conserved along the second characteristic curve, we overcome this difficulty by transforming the derivative of entropy with respect to x x into a derivative along the direction of first or third characteristic. The results demonstrate that dissipative boundary feedback control can stabilize the non-isentropic compressible Euler equations in qusi-one-dimensional nozzles.

Observer-based extended dissipative dynamic probabilistic event-triggered control of Markov jump systems subject to failures and cyber-attacks

Observer-based extended dissipative dynamic probabilistic event-triggered control of Markov jump systems subject to failures and cyber-attacks

Finite-region dissipative control for 2-D switched systems via mode-dependent average dwell time

Dissipativity is a significant concern for 2-D switched systems, but existing research often overlooks the transient dynamics occurring within a finite region. This paper aims to address finite-region dissipativity and dissipative control for a class of Fornasini-Marchesini local state-space (FMLSS) type 2-D switched systems. The analysis employs the mode-dependent average dwell time approach. Firstly, the concept of dissipativity on finite-region for 2-D switched systems is introduced. Then, a sufficient condition under which the considered systems can demonstrate the finite-region boundedness with the external disturbances is established by the special recursive formulas. Additionally, a sufficient condition for finite-region dissipativity of the considered systems is provided. Furthermore, the dissipative state feedback controller is derived to ensure the finite-region dissipativity of the closed-loop systems. To illustrate the effectiveness of the proposed controller design approach, an example is presented.

New insights on dissipative control technique for Takagi–Sugeno fuzzy system with variable time-delays and random packet dropouts

New insights on dissipative control technique for Takagi–Sugeno fuzzy system with variable time-delays and random packet dropouts

Iterative Dissipativity of Partial Difference Equation Dynamics in Open-Loop Iterative Learning Control Mode

Complex physical processes, which could evolve in both spatial and temporal dimensions and be represented by partial difference equations, could also operate in a repetitive mode with iterative learning methods as suitable control laws. For these three-dimensional systems (of the spatial, temporal, and iterative dimensions), the stability in the iterative direction is critical for many applications, which can be analyzed and synthesized under the proposed concept of iterative dissipativity. The definition of iterative dissipativity, which is first introduced in this paper, encapsulates the dominant information in both the spatial and temporal dimensions, while also placing a particular emphasis on the iteration improvement. This property allows for the derivation of sufficient conditions for asymptotic stability in the iteration direction, which are represented by linear matrix inequality criteria that can be readily solved. Performance in both the spatial and temporal dimensions can also be satisfied under this iterative dissipativity concept, even in absence of real-time feedback. Moreover, the optimization solutions of the control parameters can be determined. Finally, a thermal process and a numeric example are presented to illustrate the effectiveness of the proposed iteratively dissipative learning control approach.

Differential modulation of photosystem II photochemical efficiency in six C4 xero-halophytes.

Xero-halophytes are the salt-tolerant plants of dry habitats that adapt efficient strategies to endure extreme salt and water fluctuations. This study elucidated the adaptations related to PSII photochemistry, photoprotection, and photoinhibition in six C4 xero-halophytes (Atriplex stocksii , Haloxylon stocksii , Salsola imbricata, Suaeda fruticosa, Desmostachya bipinnata , and Saccharum griffithii ) grown in their native habitats. Chlorophyll a fluorescence quenching measurements suggested that S. imbricata and H. stocksii maintained efficient PSII photochemistry by downregulating heat dissipation and keeping a high fraction of open PSII centres that indicates plastoquinone (PQ) pool oxidation. Fluorescence induction kinetics revealed that S. imbricata demonstrated the highest performance index of PSII excitation to the reduction of end electron acceptors. S. fruticosa sustained photochemical efficiency through enhanced dissipation of excess energy and a low fraction of open PSII centres, indicating PQ reduced state. The large light-harvesting antenna size, deduced from the chlorophyll a /b ratio in S. fruticosa apparently led to the superior performance index of PSII excitation to the reduction of intersystem electron carriers. A. stocksii retained more open PSII centres with responsive non-photochemical quenching to safely dissipate excess energy. Despite maintaining the highest pigment contents and stoichiometry, A. stocksii remained lowest in both performance indices. The grass species D. bipinnata and S. griffithii kept fewer PSII centres open during photoinhibition, as evidenced by downregulation of PSII operating efficiency. The results provide insights into the differential modulation of PSII photochemical efficiency through dynamic control of photoprotective energy dissipation, PQ pool redox states, and photoinhibitory shutdown in these xero-halophytes.

Extended Dissipative Output-Feedback Controller for Autonomous Vehicle Path-Following With Steering Delays

Extended Dissipative Output-Feedback Controller for Autonomous Vehicle Path-Following With Steering Delays

Design of locally cooled step-less fan for industrial use using Arduino programming

Under the background of the development of domestic and foreign manufacturing industries and the increasing demand for industrial products at home and abroad, and under the premise of ensuring and even further reducing the manufacturing cost of manufacturers, how to effectively detect and cool the local temperature of industrial parts is a problem worth studying. After analyzing the advantages and disadvantages of traditional manual control and gear adjustment to adjust the fan, the design will be programmed using Arduino. The fan combines infrared sensor technology to detect the presence and position of parts. A temperature sensor is also set up to detect local temperatures in real-time. A fan with automatic step-less speed change according to temperature is obtained. This fan is used for heat dissipation control of local parts in industrial production, thereby reducing the cost of manual control. It further improves control accuracy and efficiency, improves product quality, and ensures production safety.

Contemporary and Conventional Passive Methods of Intensifying Convective Heat Transfer—A Review

The ever-increasing demand for effective heat dissipation and temperature control in industrial and everyday applications highlights a critical research problem. The need for development is not only in terms of providing thermal comfort to humans but also forms the basis for the efficient operation of machines and equipment. Cooling of industrial machinery and household electronic equipment is a crucial element in any manufacturing process, and the planning and design of appropriate cooling systems continues to be an integral part of the machine design and construction process. Manufacturers aim to maximize performance while minimizing size and weight. This article reviews widely used passive methods to enhance heat transfer, focusing on their effectiveness in improving convective heat transfer. The techniques examined include surface modifications and advanced materials like foamed metals and nanostructured coatings, which influence turbulence and heat transfer coefficients. The key findings demonstrate that surface roughness, perforated fins, and twisted tapes enhance fluid mixing but may increase flow resistance. The review underscores the significance of these passive methods in optimizing cooling system efficiency across various applications. Despite the variety of techniques available, many areas, especially those involving laser beam modifications, remain underexplored, indicating a need for further research in this field.

Tailoring morphological and chemical contributions of nanoscale charge transfer for enhanced triboelectric nanogenerators.

Triboelectric devices, operating through contact electrification (CE) and electrostatic induction, have shown great promise in energy harvesting applications. However, optimizing charge transfer at the interface remains crucial for enhancing device performance. This study introduces a novel approach to harnessing CE by employing morphological and chemical modifications of polymers. Our strategy involves adjusting the elastomer base to curing agent ratio to fine-tune the chemical properties of polydimethylsiloxane (PDMS) and introducing morphological modifications through a peeling and flipping (P/F) process of PDMS off the Si-substrate. Unlike conventional methods, the P/F-method minimally alters the intrinsic properties of PDMS, creating nanoscale surface corrugations adiabatically. We explore the mechanical, tribological, and electrical properties of the surface at the nano-scale and demonstrate that our approach allows for precise control of energy dissipation and electric potential at the surface, thereby optimizing charge transfer. Furthermore, we show that using a plasma-treated Si-substrate can further increase device performance up to 80% without affecting other properties. This study presents a comprehensive strategy for fine-tuning CE to enhance the performance of triboelectric nanogenerators.

Design of fuzzy dissipative sampled-data control for nonlinear wind turbine systems with random packet losses and communication delays

Design of fuzzy dissipative sampled-data control for nonlinear wind turbine systems with random packet losses and communication delays

Tailoring Coherent Microwave Emission from a Solid-State Hybrid System for Room-Temperature Microwave Quantum Electronics.

Quantum electronics operating in the microwave domain are burgeoning and becoming essential building blocks of quantum computers, sensors, and communication devices. However, the field of microwave quantum electronics has long been dominated by the need for cryogenic conditions to maintain delicate quantum characteristics. Here, a solid-state hybrid system, constituted by a photo-excited pentacene triplet spin ensemble coupled to a dielectric resonator, is reported for the first time capable of both coherent microwave quantum amplification and oscillation at X band via the masing process at room temperature. By incorporating external driving and active dissipation control into the hybrid system, efficient tuning of the maser emission characteristics at ≈9.4GHz is achieved, which is key to optimizing the performance of the maser device. The work not only pushes the boundaries of the operating frequency and functionality of the existing pentacene masers but also demonstrates a universal route for controlling the masing process at room temperature, highlighting opportunities for optimizing emerging solid-state masers for quantum information processing and communication.

High-order accurate multi-sub-step implicit integration algorithms with dissipation control for hyperbolic problems

High-order accurate multi-sub-step implicit integration algorithms with dissipation control for hyperbolic problems

Coherent interferometric control of strongly-coupled nano-electromechanical resonators

The interferometric control of dissipation in a two-port system is a fruitful concept enabling the enhancement or cancellation of the input amplitudes as a function of their relative phases. Here, beyond the canonical configuration of Coherent Perfect Absorption (CPA), we apply this concept to two simultaneously excited strongly-coupled nanoscale electromechanical resonators submitted to independently controlled phase-shifted excitations. Both subsystems are read simultaneously by optical means allowing us to completely reconstruct the signature of coherent annihilation or amplification on both quadrature. We evidence that the mechanical modes amplitude can be enhanced or inhibited with respect to the case of single port excitation while phase experiences strong variations with the excitation imbalance and phase difference. Meanwhile, phase singularities with opposite topological charges are observed for mechanical normal modes. Close to the phase singularity, we demonstrate that the input of a weak phase modulation induces a large, pure phase modulation of the normal mode. These experimental demonstrations are fully modelled via the mechanical dynamical equations of our system. The interferometric control may open avenues for low-power amplitude controlled phase modulation schemes and vice-versa for potential switches and logical gates.