Control Technique Research Articles

Importance of benzoyltransferase GcnE and lysine benzoylation of alcohol dehydrogenase AdhB in pathogenesis and aflatoxin production in Aspergillus flavus.

Lysine benzoylation (Kbz) is a newly identified post-translational modification associated with active transcription and metabolism in eukaryotes. However, whether Kbz exists in pathogenic fungi and its function remains unknown. Here, we demonstrated for the first time that Kbz is present in Aspergillus flavus and identified 60 benzoylated sites on 46 benzoylated proteins by global benzoylome analysis. Our data demonstrated that alcohol dehydrogenase B (AdhB) is regulated by benzoylation on lysine 321 (K321), and mutations of Kbz site in AdhB significantly reduced the alcohol dehydrogenase activity in vivo and in vitro. Both adhB deletion mutant and benzoylated site mutants (K321R and K321A) exhibited similar phenotype, including decreased conidiation and seed colonization, increased sclerotia formation and aflatoxin production, and more sensitive to cell wall damage stress. We also found that GcnE has benzoyltransferase activity in vitro and in vivo, and its repression leads to decreased Kbz level and enzymatic activity of AdhB. The catalytic site E139 is important for the benzoyltransferase function of GcnE. Our study uncovers a previously unknown mechanism by which benzoylation regulates AdhB activity to affect the development, secondary metabolism, pathogenicity, and stress response of A. flavus. Meanwhile, it points out the important role of Kbz in the pathogenicity of pathogenic fungi.IMPORTANCEAspergillus flavus is a ubiquitous opportunistic pathogen of plants and animals, which produces carcinogenic and toxic secondary metabolite aflatoxin. A. flavus and aflatoxin contamination have emerged as a global food safety concern. Currently, post-translational modification plays crucial modulatory roles in the fungal development and virulence, but the role of benzoylation in fungal pathogenicity remains undetermined, which limits the development of prevention and control technique. Here, we first identified 46 benzoylated proteins in A. flavus, and found that benzoyltransferase GcnE exerted effects on pathogenicity and aflatoxin production by regulating the benzoylation of AdhB. This finding not only provided valuable information for prevention and control of A. flavus contamination, but also offered basic knowledge for investigation of the regulation mechanism of secondary metabolism in other fungi.

KNOWLEDGE, ATTITUDE AND PRACTICES REGARDING SURGICAL SITE INFECTION PREVENTION AMONG STAFF NURSES IN SIR GANGARAM HOSPITAL, LAHORE

Surgical site infections (SSIs) are a significant contributor to healthcare-associated infections, leading to increased morbidity and prolonged hospital stays. Effective prevention strategies rely on healthcare professionals’ knowledge, attitudes, and practices (KAP), particularly among nurses directly involved in patient care. Objective: To assess the knowledge, attitudes, and practices regarding SSI prevention among staff nurses at Sir Ganga Ram Hospital, Lahore. Methods: A descriptive cross-sectional study was conducted among 120 nurses using a pre-validated structured questionnaire. Data were analyzed using SPSS version 26, with results presented as frequencies and percentages. Results: The majority of nurses (85%) had adequate knowledge about SSIs, with high awareness of blood sugar control (83.3%) and aseptic techniques (80.8%). Positive attitudes were prevalent, with 81.9% scoring well, and most participants agreeing on the importance of sterile materials (98.3%) and frequent dressing changes (92.5%). Adherence to good practices was noted in 87.7% of nurses, particularly in areas like skin preparation with alcohol and chlorhexidine (90%). However, gaps were identified in knowledge of specimen collection methods (64.2%) and in organizing training sessions for SSI prevention (25%). Conclusion: Nurses at Sir Ganga Ram Hospital demonstrated good KAP regarding SSI prevention, but gaps in specific practices highlight the need for targeted training and systemic improvements. Enhanced education and resource allocation can improve adherence to evidence-based guidelines, ultimately reducing the burden of SSIs in healthcare settings.

Controllable Microwave Heating for Energy-Efficient and Universal Synthesis of Atomically Dispersed Metals on Nitrogen-Doped Carbon Nanofibers.

Carbon-supported single-atom catalysts (SACs) have shown great potential in electrocatalysis, whereas traditional synthesis methods typically involve energy-intensive carbonization processes and unfavorable atomic migration and aggregation. Herein, an energy-efficient and universal strategy is developed to rapidly fabricate various SACs on nitrogen-doped hierarchically porous carbon nanofibers (M-TM/NPCNFs, TM = Fe, Co, Ni, FeCo, and FeNi) by electrospinning and controllable microwave heating technique. Such microwave heating technique enables an ultrafast heating rate (ramping to 900°C in 5 min) to greatly suppress the random migration and aggregation of metal species. Meanwhile, the energy consumption and time can be reduced to 2.5% and less than half an hour, respectively, compared to traditional pyrolysis methods. As a proof of concept, the synthesized M-Fe/NPCNFs with abundant Fe-N4 sites exhibit remarkable oxygen reduction reaction (ORR) activity with a high half-wave potential (E1/2 = 0.88 V) in alkaline media, excellent performance in Zn-air battery with a large discharge specific capacity (801 mAh g-1) and long-term cycle durability (over 1000 h), demonstrating the great potential of the microwave heating technique in efficient fabrication of SACs for energy related applications.

The Control Policy <i>M/M/c/N</i> Interrelated Queue with Manageable Incoming Rates, Reverse Balking and Impatient Customers

This study explores an interconnected M/M/c/N queueing model that incorporates reverse balking, reneging, a control technique, and adjustable arrival rates. In reverse balking, the likelihood of a visitor deciding to join or leave a queue is influenced by the current system size, with a higher probability of joining as the system size grows. Conversely, long wait times can lead to customer impatience, causing them to leave the queue before receiving service (reneging). Service begins with the arrival of the initial customer (TL) and continues until the system is empty. We are developing a multi-server queueing system with adjustable arrival rates that includes reverse balking and considers impatient customers. For this model, we determine the steady-state condition and performance metrics such as average waiting time and average system size.

Tracking and Fault-Tolerant Controller Design for Uncertain Steer-by-Wire Systems Using Model Predictive Control

This study presents a tracking and fault-tolerant controller architecture for uncertain steer-by-wire (SbW) systems using model predictive control in the presence of actuator malfunction and the nonlinear properties of tire lateral stiffness coefficients. By changing the internal model, the model predictive control (MPC) technique was used to achieve optimal tracking performance under the actuator output limitation variation problem and uncertain system parameters. System parameters and state estimates were simultaneously provided by the fault detection and isolation modules to detect actuator failure using the coupling estimation approach. The estimation accuracy was further improved by considering the replacement errors as virtual noise, which was also estimated during the estimation process. Simulation and experimental results demonstrate that the proposed fault-tolerant control technique can identify motor faults and conduct fault-tolerant control based on fault identification, showing good front-wheel steering angle tracking performance under both normal and fault conditions.

Energy Management in a Renewable-Based Microgrid Using a Model Predictive Control Method for Electrical Energy Storage Devices

In this paper, an energy management strategy is developed in a renewable energy-based microgrid composed of a wind farm, a battery energy storage system, and an electolyzer unit. The main objective of energy management in the studied microgrid is to guarantee a stable supply of electrical energy to local consumers. In addition, it encompasses hydrogen gas production by using part of the available excess energy in the system, which has some economic benefits. Also, energy management can protect the battery bank from damage by preventing the possibility of it being overcharged. These objectives should be achieved by developing a robust and effective control technique for DC-DC converters that are connected to energy storage devices. For this purpose, an advanced control technique based on Model Predictive Control, which is recognized as a popular control technique for industrial and process applications, is developed. This technique has a fast dynamic response and good tracking features and is simple to implement. The simulation results prove the effectiveness of the proposed control strategy and control technique for energy management in the studied renewable energy-based microgrid.

Decomposition thermokinetics and heat balance analysis of depressurized methane hydrate deposits under poor heat transfer conditions

Methane hydrate is an important form of natural gas resource found in submarine deposits, with exploitation efficiency mainly determined by in-situ hydrate decomposition. During the depressurization exploitation process of large-scale hydrate deposits, the heat transfer situation of far-wellbore deposits is highly likely to be worse than that of near-wellbore deposits; However, the thermodynamic and kinetic characteristics of hydrate decomposition under poor heat transfer conditions are still unclear, particularly lacking heat balance analysis theory. This study adopted an external temperature control technique in experiments to worsen the heat transfer situation and investigate its effects on the decomposition thermokinetics of depressurized methane hydrate deposits to 2.9 MPa. The stable decomposition rates of methane hydrates under different heat transfer situations were found to be linear with temperature difference, and decomposition stagnation was observed as heat transfer worsened. Based on these results, a novel heat balance model of depressurized deposits with hydrate decomposition was developed, which can accurately predict the dynamic temperature response of hydrate decomposition deposits with a deviation of no >8.9 %. In addition, the low hydrate decomposition rate under a worse heat transfer condition induced synergistic fluctuations in pressure and temperature, which can be improved with progressive warming. This study reveals the thermodynamic and kinetic behaviors of methane hydrate decomposition under poor heat transfer conditions for the first time and can help predict the spot exploitation characteristics of far-wellbore hydrate deposits.

EDUKASI PENDEKATAN PARTISIPATIF DALAM PENGENDALIAN HAMA BURUNG DI PERTANAMAN PADI DI KECAMATAN TAMBAN CATUR KABUPATEN KAPUAS KALIMANTAN TENGAH

Bird pests in rice cultivation pose a serious problem that directly affects harvest yields and farmer welfare, particularly in Tamban Catur District, Kapuas Regency, Central Kalimantan. This study focuses on implementing an educational program and field practices for bird pest control through a participatory approach. The objective of this research is to enhance farmers' understanding and skills in independently and sustainably managing bird pests. The methods used include training, extension services, and field assistance, involving active participation from farmers. The results show that this program effectively increased farmers' knowledge of bird pest control techniques and significantly reduced harvest losses caused by pest attacks. This participatory approach is expected to be widely applicable in other regions to support food security and improve farmers' welfare.

Robust Generalized Super‐Twisting Sliding Mode Control Design for Optimal Performance in Three‐Phase Grid‐Connected Photovoltaic Systems

ABSTRACTThis article introduces a third‐order super‐twisting sliding mode control (Gen‐STSMC) algorithm designed for the secure operation of a grid‐connected photovoltaic (PV) system. The improved method changes the traditional super‐twisting sliding mode control (STSMC) technique by incorporating both a linear term and a higher power term to reduce convergence time and chattering effects. This strategy generates the optimal control signals to regulate the output power of the PV system by compensating the state‐dependent uncertainties using the linear and growing term. The controller's stability analysis is conducted to demonstrate its rapid convergence compared to PI and conventional STSMC scheme. A comparative simulation study against PI and STSMC is conducted to showcase the controller's rapid convergence and robust performance in various grid‐connected PV system scenarios. Experimental tests are also performed to validate the controller's effectiveness in maintaining stable power generation in the presence of environmental fluctuations and DC link voltage variations.

New Insight of Nanosheet Enhanced Oil Recovery Modeling: Structural Disjoining Pressure and Profile Control Technique Simulation

This study presents a novel Enhanced Oil Recovery (EOR) method using Smart Black Nanocards (SLNs) to mitigate the environmental impact of conventional thermal recovery, especially under global warming. Unlike prior studies focusing on wettability alteration via adsorption, this research innovatively models ‘oil film detachment’ in a reservoir simulator to achieve wettability alteration. Using the CMG-STARS (2020) simulator, this study highlights SLNs’ superior performance over traditional chemical EOR and spherical nanoparticles by reducing residual oil saturation and shifting wettability toward water-wet conditions. The structural disjoining pressure (SDP) of SLNs reaches 20.99 × 103 Pa, 16.5 times higher than spherical particles with an 18.5 nm diameter. Supported by the Percus–Yevick (PY) theory, the numerical model achieves high accuracy in production history matching, with oil recovery and water cut fitting within precision error ranges of 0.02 and 0.05, respectively. This research advances chemical EOR technologies and offers an environmentally sustainable, efficient recovery strategy for low-permeability and heavy oil reservoirs, serving as a promising alternative to thermal methods.

A novel Zero Back Power Flow (ZBPF) controlled DAB for DC bus stability and energy storage integrations in hybrid DC/AC off-grid systems

The paper presents an innovative approach for integrating energy storage devices into hybrid AC/DC grids to ensure a consistent power supply for modern loads. It introduces a Zero Back Power Flow (ZBPF) enabled bi-directional Dual Active Bridge (or, Direct AC-AC Boost) (DAB) controller strategy aimed at enhancing the power handling capacity DABs, while offering adaptable control for the microgrid system. Utilizing the proposed ZBPF control technique, the system endeavors to improve the power quality of the high-frequency AC link and regulate power transfer across DAB converter. Furthermore, a power management control strategy is described to facilitate efficient power flow among the diverse sources and loads within the hybrid off-grid system via battery system. By incorporating multiple utility features, the system aims to maintain stable bus voltages and mitigate potential power supply reliability issues. The paper concludes with simulation results validating the efficacy of the proposed ZBPF DAB control algorithms in grid forming operational modes, demonstrating the feasibility and effectiveness of the proposed solution. Additionally, the proposed ZBPF controller is tested on a hardware platform using batteries. An experimental setup has been conducted to verify the operation of the proposed ZBPF modulation scheme for a DAB converter in a practical setting. It involves implementing the ZBPF modulation scheme using a Hardware-in-the-Loop (HIL) setup and testing the DAB converter under both forward and reverse power flow modes.

Organic Mulching: A Sustainable Technique to Improve Soil Quality

Organic mulching is a promising technique for sustainable weed control and soil management, as it enhances crop growth, soil quality, water retention, and erosion control. This research evaluated the effects of organic mulches—wheat straw, wood chips, spray cellulose pulp, compost, and a cover crop mixture—on the physical–mechanical properties of organic garden soil transitioning to natural farming. The controlled soil received no mulch. The soil was fertilized with mature bovine manure prior to a three-year crop rotation of tomato, lettuce, and savoy cabbage. Mulching occurred after the second harrowing and before transplanting. Soil analyses were conducted to assess changes after three years. Soil organic carbon levels increased significantly in soils treated with compost, cover crops, or chipped wood mulching (6.81, 3.17, and 2.07%, respectively) compared to other treatments (1.24% in the control plot). Different kinds of mulch had a significant impact on soil’s physical–mechanical parameters. Compost, compared to the control, decreased the bulk density (from 1.22 to 0.89 Mg m−3), increased the infiltration rate (from 8.53 to 21.07 L m−2), and reduced compressive deformation (from 37.08 to 18.23%). The composition of mulch materials, specifically their nitrogen and carbon concentrations, C/N ratio, and moisture content, plays a significant role in influencing changes in soil properties.

Control of Acoustic Tone Formation using Shape Geometry Modifications and Jet Blowing in a Cavity experiencing Supersonic Flow

Acoustics tones have caused significant damage to sensitive electronic equipment and aircraft respectively. The effects become severe in cavities experiencing turbulent flows and could lead to human fatalities. Studies have compared the effects of cover plate (CP) and jet-blowing (JB) systems in suppressing the propagation of these undesirable effects. The sound pressure levels (SPL) were observed to decrease by 10% and 3% in the former and latter respectively. This study critically examines the combined effect of CP geometry modifications, jet orifice positions as well as integration with other established flow control techniques (FCT) with the possibility of achieving further attenuation in the system. Geometric sizes of the CP are set to 20%, 25% and 30% of the cavity length, with a length-to-depth ratio (l/d) of 5.07 and simulated in a flow field with a Mach number of 1.5. Also, four orifices for jet blowing are varied on the cavity leading and trailing edge wall. The trailing edge modification and trailing edge curvature are also implemented on the cavity. The k-ꙍ turbulence model and second-order discretization method are used to perform the computation. Results show that the trailing edge region produced the largest pressure fluctuations. Also, it was observed that longer cover plates (0.3l) permit the formation of self-oscillating frequencies as the flow field is brought closer to the trailing edge. However, the further inclination of the trailing wall will ensure prompt evacuation and dissipation of the flow turbulence energy. At the trailing edge, the jet-blowing control technique successfully attenuated approximately 10dB in SPL, though a significant amount of turbulence was introduced into the system. Overall, the trailing edge modification, inclined cover plate with a 0.25l and jet blowing on the trailing and leading edges produced an approximate 27.5% reduction in acoustic tone suppression.

Secure control for uncertain nonlinear cyber–physical systems: A prescribed-time scheme based on temporal scaling

In this paper, the prescribed-time secure control is explored for uncertain nonlinear cyber–physical systems through temporal scaling transformation and gain control technique, where the nonlinearity is more generic than common linear growth conditions due to the presence of large uncertainties and low-order states. Given that security risks exist in open networks, the impact of deception attacks is considered, whereas, this prevents the gain control technique from being applied directly to control design. To lift the restriction, a novel auxiliary system is firstly constructed to cleverly turn the secure control to the boundedness control of the auxiliary system. Next, a crucial bridge, temporal scaling transformation, is employed to transform the control issue in the finite time into infinite time, which opens up more possibilities for solving studied issues. Then, by the gain control technique, a Zeno-free secure control strategy with dynamically adjustable triggering mechanism is devised, which successfully ensures the convergence of system states within the prescribed time meanwhile counteracting deception attacks. Further, an improved nonlinearity, i.e. containing both low-order and high-order states, is discussed. Particularly, the proposed control strategies not only avoid real-time control updates, but also the gains therein handle system nonlinearities efficiently. Eventually, the validity of major results is verified via simulation examples.

Static pinning synchronization control of self-triggered coupling dynamical networks

In this paper, a new static pinning intermittent control based on resource awareness triggering is proposed. A multi-layer control technique is used to synchronize the coupled neural network. First, a hierarchical network structure including pinned and interaction layers is induced using each pinning strategy. Second, using the ideas of average aperiodic intermittent control (AIC) rate method and constructing an auxiliary function, a new lemma is proposed for the pinning intermittent synchronization of coupled networks, where the upper/lower bound restrictions on each control width for AIC are relaxed. Third, to obtain the desired synchronization behavior, a self-triggering mechanism (STM) is proposed to execute the AIC of the pinned and interaction layers. Moreover, the proposed STM is effective for the actuation of the static pinning impulsive control. The static pinning method modifies the single pinning and switching pinning impulsive control. Finally, the proposed results are applied to Chua’s circuits, oscillators and small-world networks. Experimental results show the performance of the proposed STM which reduces 34.58% the number of control updates compared to a periodically intermittent event-triggered scheme. Further, for large-scale coupled networks, the N-dimensional Laplacian matrix LV can be decomposed into sp×sp and N−sp×N−sp dimensions by hierarchical method, thus reducing the complexity of calculation.

Controllable synthesis of N-rich defective carbon materials for aqueous supercapacitors: Towards a trade-off between gravimetric and volumetric capacitance

The conversion of biomass into porous carbon with high specific surface area (SSA) could be applied in the field of supercapacitors, which realised the resourceful use of biomass. However, the increase in SSA provided carbon materials with lower volumetric capacitance, thereby limiting the development of carbon-based supercapacitors (SCs). To trade off gravimetric and volumetric capacitance, the active nitrogen doping strategy was an effective route. Herein, nitrogen-rich micro-mesoporous composite carbon materials were synthesised from forestry waste (bamboo) as raw material, with guanidine carbonate as N-rich agent and KHCO3 as green activator. The N-rich agent exhibited multiple roles in the co-pyrolysis process, which were pore creation and heteroatom doping. In this paper, the correlation between the type of N-rich agent, the addition amount and the pre‑carbonization temperature and the electrochemical properties of carbon materials were investigated. Due to the multifunctionality of guanidine carbonate, the carbon material exhibited excellent SSA (1469.14 cm2/g), outstanding microporous structure, and abundant reactive N sites, which facilitated the efficient transport of electrolyte ions. Among them, the best carbon material (BC/CN-400-1) showed a high gravimetric capacitance of 376.25 F/g, demonstrating a volumetric capacitance of 355.54 F/cm3 at the same time. In addition, the aqueous symmetrical supercapacitor (BCN//BCN) displayed remarkable cycling stability (94.35 %). The BCN//BCN achieved an energy density of 15.64 Wh/kg at a power density of 75 W/kg. In summary, this study proposed a controllable N-atom doping technique, which offered a feasible route for the synthesis of N-doped hierarchical nanomaterials. Meanwhile, using forestry wastes as raw materials for the preparation of high-performance carbon-based supercapacitors facilitated resources utilization of biomass and sustainable development, providing a reference for the fabrication of N-rich biomass-derived carbon materials.

Metaheuristic algorithm based PID controller using MRAC techniques for control of a nonlinear system

Metaheuristic algorithm based PID controller using MRAC techniques for control of a nonlinear system

A twist of the tail in turning maneuvers of bird-inspired drones.

A banked turn is a common flight maneuver observed in birds and aircraft. To initiate the turn, whereas traditional aircraft rely on the wing ailerons, most birds use a variety of asymmetric wing-morphing control techniques to roll their bodies and thus redirect the lift vector to the direction of the turn. Nevertheless, when searching for prey, soaring raptors execute steady banked turns without exhibiting observable wing movements apart from the tail twisting around the body axis. Although tail twisting can compensate for adverse yaw, functioning similarly to the vertical tail in aircraft, how raptors use only tail twisting to perform banked turns is still not well understood. Here, we developed and used a raptor-inspired feathered drone to find that the proximity of the tail to the wings causes asymmetric wing-induced flows over the twisted tail and thus lift asymmetry, resulting in both roll and yaw moments sufficient to coordinate banked turns. Moreover, twisting the tail induces a nose-up pitch moment that increases the angle of attack of the wings, thereby generating more lift to compensate for losses caused by the banking motion. Flight experiments confirm the effectiveness of tail twist to control not only low-speed steady banked turns but also high-speed sharp turns by means of coordinated tail twist and pitch with asymmetric wing shape morphing. These findings contribute to the understanding of avian flight behaviors that are difficult to study in controlled laboratory settings and provide effective control strategies for agile drones with morphing aerial surfaces.

Shape Control Techniques for Earthquakes Structures in Hospital Buildings Using ETABS Software

Earthquakes are a natural phenomenon that can cause damage to multi-storey buildings such as hospital buildings. The occurrence of earthquakes cannot be predicted, so deeper studies are needed to analyze building structures, especially to minimize ground movements when activities caused by tectonic earthquakes occur. Therefore, a structural analysis model was carried out to fulfill the protection requirements for buildings using the time history method based on Etabs V.18 software with the aim of analyzing the structure of safety requirements according to established standards and reviewing deviations between levels and ATC-40 by considering the total maximum speed. Implementation of the use of Etabs V.18 software in analyzing building structures using the time history method, then to support the analysis of this research, the building model parameters were reviewed using one earthquake accelerogram input. The research results show that in the X direction the largest inter-floor deviation is 50.90, and in the Y direction the largest inter-floor deviation is 50.90. Based on the ATC-40 measurement results, the building is included in the Immediate Occupancy (IO) performance level, with a maximum total deviation value below the limit of 0.01.

Fractional order pole fixed second order generalized integrator based control for grid connected solar photovoltaic system

AbstractIn this article, the development of multi‐functional grid connected solar photovoltaic (PV) system using improved Fractional order Control theory‐based Pole fixed Second Order Generalized Integrator (FO‐PFSOGI) is proposed. The fractional order (FO) control technique offers an advantage to adjust the fixed structure of the integer order and provide additional degree of freedom to achieve accurate response during the system operation. The FO‐PFSOGI control technique is used to extricate fundamental constituent of the non‐sinusoidal load current. The PV system is competent of feeding the local load requisite and may also inject surplus power into the grid. The voltage source converter (VSC) utilized in the grid‐connected system can also be operated as power quality compensator, taking care of harmonics, unbalancing and excess reactive power demand of the local load. The feasibility of multifunctional operations of the converter is established in this article, thus achieving maximum utilization of the power electronics used in the system and reducing the overall cost. A performance comparison of the developed control technique is presented with the conventional techniques in terms of harmonic compensation, weight convergence and computational complexity. The implementation of the controller is modest and extracts fundamental quantities without any phase delay under different loading conditions. The developed system is validated using both simulation and experimental study. A scaled down experimental setup of grid‐connected PV system is implemented in the laboratory and real time performance of the FO‐PFSOGI is demonstrated using variations in system load and PV irradiance.