Sugarcane is a key economic crop in subtropical and tropical regions, serving as a major raw material for the food and biofuel industries. However, its cultivation is severely affected by the sugarcane borer, a destructive pest. To mitigate this issue, biological control strategies—using natural enemies to regulate pest populations—offer an environmentally friendly alternative to chemical pesticides. This study proposes a tensor product–based fractional-order sliding mode control (TP-FOSMC) approach to formulate an effective biological control policy for a nonlinear pest–parasitoid agroecosystem. The controller design utilizes tensor product model transformation (TPMT) to facilitate the synthesis of the fractional-order sliding mode controller, which enhances system robustness and significantly reduces chattering in the control inputs. System stability is verified using the Lyapunov stability theorem. Numerical simulations under bounded disturbances demonstrate that the proposed TP-FOSMC effectively regulates both pest and parasitoid populations to their desired levels. Compared with the state-dependent Riccati equation (SDRE) and tensor product–based conventional sliding mode control (TP-SMC) strategies, the proposed method achieves faster convergence and substantial chattering reduction, confirming its robustness and practical feasibility for sustainable pest management.

Climbing robots equipped with magnetic adhesion are widely used for inspecting ferromagnetic structures; however, the limited adhesion force-to-mass ratio remains a primary challenge. Therefore, the main aim of this paper is to design a novel omni-magnetic wheel for a climbing inspection robot on ferromagnetic flat surfaces, using the reliable maximum force-to-mass ratio, to achieve high maneuverability by integrating an embedded cylindrical permanent magnet disc. The experiment and finite element analysis (FEA) were conducted using a tensile test machine and COMSOL Multiphysics 6.1, respectively, to validate the proposed three-dimensional model. Geometric parameter study via COMSOL helps determine relationships between parameters and magnetic adhesion force & mass, and the development of a graphical user interface (GUI) for design guidance of magnetic omni wheels using MATLAB. The optimum design parameter values were selected from the geometry parameter database, based on a balance between minimum mass and the minimum required magnetic force to prevent detachment during climbing, which was used to develop the prototype of the climbing robot’s omni-magnetic wheels for locomotion tests. It has achieved stable maneuverability without tilting/traction on the vertical ferromagnetic flat surface at an appropriate speed with a payload.

This research investigates the potential of elliptical web openings to enhance web-post buckling resistance in steel beams subjected to concentrated mid-span loads, compared with circular openings of equivalent area. Key geometric parameters were systematically varied, including the circular web opening diameter- to-beam height ratio (d/h), spacing-to-circular opening diameter ratio (s/d), the aspect ratio of elliptical openings (mj/r), and the orientation angle (0) of elliptical openings. Utilizing finite element analysis (FEA) with ANSYS software, buckling and post-buckling analyses were performed using a geometric nonlinear approach with imperfections, based on S355 steel properties. The parametric study encompassed 4,455 numerical models. Results indicate that optimized elliptical openings significantly enhance buckling resistance compared to circular openings. Optimal aspect ratios for elliptical openings achieved up to a 15% improvement in buckling resistance compared to circular openings of the same area and spacing. Higher d/h ratios were found to reduce buckling resistance by decreasing the tee section height, while increased s/d ratios improved shear capacity by distributing stresses more effectively. Optimizing mj/r ratios for elliptical openings further enhanced buckling resistance without altering the spacing, leading to approximately a 13% increase in structural stability. Additionally, adjusting the orientation angle to counterclockwise positions reduced stress concentrations, resulting in a 15% improvement in buckling resistance. An Artificial Neural Network (ANN) model developed using MATLAB's Neural Net Fitting Tool (nftool) demonstrated high predictive accuracy, with a Mean Absolute Percentage Error (MAPE) of 0.17%. These findings offer valuable insights for optimizing the design of perforated steel beams, contributing to more efficient and resilient structural engineering solutions.

Terminal synergetic control (TSC) is proposed as a control strategy for the temperature management of a plate heat exchanger. The controller is designed by incorporating a selected macro variable with a time-varying sliding surface. The primary objective is to maintain precise control over the outlet temperature of the cold water. To assess the convergence characteristics of the newly proposed TSC approach, the simulation results achieved using TSC featuring a time-varying macro variable are compared to those obtained from the conventional synergetic control (SC) method. With an appropriate macro variable, the simulation results indicate a notable improvement in the convergence rate provided by our designed TSC method, compared to the conventional one. The desirable property of control input, the chattering-free condition, achieved by both TSC and SC approaches emphasizes the advantage of the synergetic control-based techniques over the conventional sliding mode controller. In conclusion, synergetic control-based techniques offer superior potential solutions for nonlinear feedback control problems.

Sugarcane is an important agricultural commodity in economics that has been harmed by the invasion of sugarcane borer. Establishing a biological pest control strategy for sugarcane using their natural enemies can both protect agricultural products from pest invasion and the environment from chemical toxicity. In this regard, feedback control emerges as a practical and feasible approach to effectively implement the biological control strategy for managing the sugarcane borer. In this work, the terminal synergetic controller (TSC) was designed to develop a control strategy containing multiple inputs. The controller design was conducted based on the pest-parasitoid model. In the design procedure, the auxiliary system was employed to compensate for the input saturation effects. The control stability was conducted through the Lyapunov stability theorem. To confirm the capability and performance of the proposed strategy, the simulation results demonstrate that it can effectively regulate pest population densities at the desired level, comparable to both the conventional sliding mode control (SMC) and verticum-type control (VC) strategies. However, what sets it apart is that the terminal synergetic controller provides the preferable characteristics for controlling the sugarcane borer population which are the finite-time convergence of the control system, and the absence of chattering phenomena in the control inputs.

This research introduces a terminal synergetic controller (TSC) designed for the active suspension system of automobiles through the implementation of the dragonfly algorithm (DA).The proposed controller aims to enhance the dynamic performance of a car's suspension using the DA in tuning the system parameters.The stability of the designed controller is proved through the application of Lyapunov stability theory.Through iterative optimization processes, the TSC approach seeks to achieve an optimal balance between ride comfort and vehicle handling.The simulation results demonstrate that the proposed controller enhances convergence properties and alleviates the presence of chattering.The results indicate that the proposed approach with the optimal parameters provided insights into its potential application in improving the overall suspension system.

Visceral Leishmaniasis (VL) is a prevalent vector-borne disease that affects both human and animal populations in subtropical and tropical regions, contributing to a substantial mortality rate. Establishing efficient control policies is crucial to eradicating the VL epidemic. The VL epidemic system, containing reservoirs, vectors, and human populations, can be accurately modeled through differential equations. Managing the VL epidemic under multiple control policies can be considered a high-order nonlinear feedback control challenge. This study explores the application of Terminal Synergetic Control (TSC) to eradicate Zoonotic Visceral Leishmaniasis (ZVL). Notably, Synergetic Control (SC) is one of the suitable feedback control methods for manipulating high-order nonlinear systems, providing practical control inputs because of their chattering-free behavior. Additionally, the convergence properties of the control system can be enhanced through terminal attraction. Optimization of control parameters within the system is achieved through the integration of control mechanisms by the Dragonfly Algorithm (DA). The results demonstrate that the multiple control policies synthesized by the TSC method effectively regulate subpopulations in alignment with the specified control objectives. Furthermore, the enhanced convergence rate achieved by the TSC method, in comparison to the SC method, serves as evidence of TSC's effectiveness in guiding the dynamics of ZVL epidemic eradication. This research underscores the potential of the TSC method, utilizing optimal control parameters provided by the DA, to achieve targeted outcomes with improved convergence properties.

Vibration is challenging and significant in solving engineering problems. The issue of vibration in loaded objects by utilizing a three-dimensional model and experiments. Typically, an object is subjected to a random frequency, which changes the notch shape depending on the frequency model. The investigations determined the performance difference by conducting modal analysis with the finite element method and examining the various forms of each mode. We simulated metal plates with V notch and multiple notch locations on both sides and one side of the notch. The test kits included an accelerometer and a force sensor for correcting the national frequency via Simulink Matlab® and verifying the result from the finite element methods. The V-shaped vibration testing provided significant insights into its accuracy and potential for predicting damage and fracture through experimentation and the finite element method. The tested specimen analyzed the behavior of two models and found that the two V-shaped exhibited varying natural frequency values. Specifically, the double-sided V-shaped increased natural frequency, whereas the single-sided notched V-shaped cutting showed a significant decrease in natural frequency. Accordingly, this investigative approach, the result of the experiment, and the finite element shows that correlation disposition can be utilized to forecast various random frequencies for vibration analysis.

Abstract Sugarcane is an important agricultural commodity in economics that has been harmed by the invasion of sugarcane borer. Establishing a biological pest control strategy for sugarcane using their natural enemies can both protect agricultural products from pest invasion and the environment from chemical toxicity. In this regard, feedback control emerges as a practical and feasible approach to effectively implement the biological control strategy for managing the sugarcane borer. In this work, the terminal synergetic controller was designed to develop the control strategy containing multiple inputs. The controller design was conducted based on the pest-parasitoid model. In the design procedure, the auxiliary system was employed to compensate for the input saturation effects. The control ecosystem stability was conducted through the Lyapunov stability theorem. To confirm the capability and performance of the proposed strategy, the simulation results show that the proposed strategy has the capability to regulate pest population densities at the desired level, akin to the conventional sliding mode control strategy. However, what sets it apart is that the terminal synergetic controller provides the preferable characteristics for controlling the sugarcane borer population which are the finite-time convergence of the control system, and the absence of chattering phenomena in the control inputs.

Abstract Sugarcane is an important agricultural commodity in economics that has been harmed by the invasion of sugarcane borer. Establishing a biological pest control strategy for sugarcane using their natural enemies can both protect agricultural products from pest invasion and the environment from chemical toxicity. In this regard, feedback control emerges as a practical and feasible approach to effectively implement the biological control strategy for managing the sugarcane borer. In this work, the terminal synergetic controller was designed to develop the control strategy containing multiple inputs. The controller design was conducted based on the pest-parasitoid model. In the design procedure, the auxiliary system was employed to compensate for the input saturation effects. The control ecosystem stability was conducted through the Lyapunov stability theorem. To confirm the capability and performance of the proposed strategy, the simulation results show that the proposed strategy has the capability to regulate pest population densities at the desired level, akin to the conventional sliding mode control strategy. However, what sets it apart is that the terminal synergetic controller provides the preferable characteristics for controlling the sugarcane borer population which are the finite-time convergence of the control system, and the absence of chattering phenomena in the control inputs.

This article proposes the design of a sliding mode controller with a time-varying sliding surface for the plate heat exchanger. A time-varying sliding mode controller (TVSMC) combines the benefit of the control system’s robustness and convergence rate. Using Lyapunov stability theory, the stability of the designed controller is proved. In addition, the controller parameters of the designed controller are specified optimally via the dragonfly algorithm (DA). The input constraint’s effect is considered in the controller design process by applying the concept of the auxiliary system. The bounded disturbances are applied to investigate the robustness of the proposed techniques. Moreover, the quasi-sliding mode controller (QSMC) is developed as a benchmark to evaluate the convergence behavior of the proposed TVSMC technique. The simulation results demonstrate the proposed TVSMC with the optimal parameters provided by the DA algorithm (TVSMC+DA) can regulate the temperature to the desired level under bounded disturbances. When compared to the QSMC method, the TVSMC+DA performs significantly faster convergence speed and greater reduction in chattering occurrence. The results clearly indicate that the proposed controller can enhance convergence properties while being robust to disturbances.

This paper aims to present the design and prototype of an inspection robot that can perform both horizontal and vertical locomotion in ferromagnetic pipelines. The proposed robot applies to a range from 5-inch (127 mm) diameter pipes to flat plates. The train-like robot is mainly composed of three sealed modules with omnidirectional driving wheels for longitudinal and transverse movements. Permanent magnets were designed to provide sufficient magnetic adhesion between the robot and the ferromagnetic surface of the pipes. The internal condition of the pipe can be monitored visually through cameras and sensors. Specific experimental conditions have been carried out to validate the robot’s capabilities, including maximum speed, payload capacity, and vertical climbing distance. The experimental results also show that the robot is capable of passing through a straight pipe and elbow fitting in both upward and downward directions.

The Hepatitis-B (HBV) epidemic's dynamic can be presented as a compartment model.Determining the HBV epidemic control strategy can be considered a nonlinear feedback control problem.The sliding mode controller (SMC) is an effective feedback control method for controlling the dynamical system under disturbances.Recently, the SMC based on fractional order calculus can provide preferable characteristics for a control system such as robustness and convergence rate.In this study, the HBV epidemic system's control policy is proposed using the fractional order sliding mode controller (FOSMC).The control policy with multiple measures including vaccination, isolation, and treatment is formulated to manipulate the susceptible and the infected subpopulations to the desired level.The Lyapunov-based approach is proven for stability analysis.The control policy is applied to the simulation example to verify the feasibility of the proposed FOSMC method.The simulation results are compared with those of the integer order SMC.By the proposed method, the results reveal that the susceptible and infected subpopulations are driven to the desired levels under disturbances with a higher convergence rate compared to that of the integer one.Moreover, the proposed FOSMC method can reduce the chattering occurrence which is the primary drawback of the SMC method.

Hepatitis B virus (HBV) infection is one of the life-threatening diseases due to causing cirrhosis and liver cancer in the infected person.Setting the policy to control the HBV epidemic is an important issue that can be achieved by using feedback controller design procedure through the compartment model.In this article, the sliding mode controller with a time-varying sliding surface was utilized to set the multiple measures control policy for controlling the HBV epidemic.The stability of the control HBV epidemic system was examined.The simulation of the control system was conducted to confirm the feasibility of applying the time-varying sliding mode controller for setting the HBV control policy.The simulation results showed that the designed control policy could drive the target subpopulation to the desired levels.The convergence rate of the control HBV system could be improved.Thus, the time-varying sliding mode controller is a feasible approach to set the measures for controlling the HBV epidemic.

This paper introduces the design principles for an active knee exoskeleton for sit to stand movement based on 4 attachments. Assistive devices enable people to regain their mobility, a critical function of human life. Many exoskeletons currently exist, however, most products assist in gait cycles of walking and running. Because the range of motion in these activities are relatively small and requires little torque, they’re not suitable for activities such as sit to stand or stair climbing. The design presented aims to achieve 50% of the required torque for sit to stand movement for an 80 kg male. Comfort and safety are also important factors to maximize via mechanical design. In this paper, Arduino Mega 2560 board is employed to control the motion of the exoskeleton. The Arduino board serves as the microcontroller to control a stepper motor while logic gates and EMG sensors provide the input signal. The experimental results show significant decreases in metabolic metrics when using the exoskeleton, suggesting that the exoskeleton is successful in assisting the user. 

Various industrial structures or machines mostly consist of different shapes of ferromagnetic curvature surfaces. The magnetic wheel climbing robot is the suitable approach for achieving both adhesion and locomotion of the inspection robot. However, the adjustable magnetic force for robot adhesion is necessary, especially when the thickness of the surface is not uniform or the variation of the air gap between the magnetic adhesion units caused by the curvature of the surface. This can lead to the insufficient adhesive force. Furthermore, unnecessary driving torque of the motor to actuate the climbing robot from the over design of the magnetic adhesive force from the magnetic wheels can be avoided. Due to the level of the adaptive adhesive force is necessary to be considered, we designed the adaptive electromagnetic adhesive force mechanism for the curvature surface climbing robot with magnetic wheels. The PID controller was employed to control the electromagnetic force, and the adhesive force was measured by a load cell. This measurement signal was used as a feedback signal. In the paper, we investigated the capability of this adjustable magnetic force system. Five aspects of experimentation were implemented. It was clear that the light weight electromagnetic force adjustment mechanism could provide the flexibility to regulate the adhesive force for the magnetic robot while traveling on the ferromagnetic curvature surface.

In case study, the dynamical behavior of various systems including intracranial pressure (ICP), cerebral perfusion pressure (CPP), intraocular pressure (IOP), arterial blood pressure (ABP), and blood flow (BF) are studied based on the equivalent electrical model. The healthy people from clinical data are used for study those behaviors. Resistor-Capacitance network is constructed to simulate ICP inside the skull, IOP of the retinal vessel, CPP in the skull. Moreover, ABP from the heart (85 - 120 mmHg) and Intraspinal Pressure (ISP) (50 - 60 mmHg) are applied as inputs to this model. The results show the value of ICP of normal state, IOP, and CPP in the skull are 5-15 mmHg, 20-35 mmHg, and 65-90 mmHg respectively. For the phase relationship among ABP, CPP, IOP, and ICP are synchronized. The differential phase between ABP and BF is 0.25 to 0.5 second where ABP waveform was leaded BF waveform. Our model is verified by clinical data from noninvasive measuring method. This model provides a clear explanation of the interaction behavior between ICP, CCP, IOP, ABP and BF of healthy individuals.

The mathematical model of HIV dynamical system explains the interaction between the immune system and virus. It represents the relationship among population size of uninfected CD4+ cells, infected CD4+ cell, and virus. The aim of the treatment is to drive the amount of uninfected CD4+ cells to the desired level and the amount of both infected CD4+ cells and virus particles approach to zero as time increased. The main objective of this study is to apply the fractional order sliding mode control (FOSMC) method to regulate HIV infection. The performance of the control method was investigated via simulation. According to the simulation of the controlled HIV system, the state variables approach to the desired values. Thus, it is feasible to apply the FOSMC method to define the treatment of the HIV infection system.

Hemodynamics studies of cerebral blood and governing of cerebrospinal fluid (CSF) are important circumstances for diagnosis of many diseases associated with human brain like hydrocephalus, brain trauma and increased intracranial pressure (ICP). CSF is genesis by epithelial cells of choroid plexuses in ventricles and secretes to subarachnoid spaces (SAS) and lumbar CSF spaces through the cerebral aqueduct. Non-invasive methods on computational analysis and mathematical models to predict dynamic behavior and CSF motion are yet to be developed. This study is extended to develop a mathematical model to predict CSF motion through the cerebral aqueduct based on an arterial compliance. Throughout of our study, region of interest (ROI) was the cerebral aqueduct and considered both blood vessel and aqueduct walls as linear spring system of two degree of freedom. Results of math model showed, contraction and dilation of arteries contributes significant role for governing force of CSF by inheriting pulsatile motion, which synchronized with pulsatile motion of blood, but with having a phase shift with a blood motion. Keywords-Cerebrospinal fluid, cerebral aqueduct, Arterioles dilation, Math model.

purpose of this study is to experimentally determine the optimal blend rate of ethanol-gasoline fuels in order to maximize the brake thermal efficiency of a commercial SI engine. In this study, the engine performance, in terms of brake torque and brake specific fuel consumption, has been investigated with variation of volumetric mixing ratio between 87.5-octane gasoline and 99.5%-purity ethanol (E10, E20, E30, E40, E50, E60, E70, E85, and E100). The experiment has been conducted at different engine speeds and percentages of intake-throttle opening. The tests were performed at a constant compression ratio. The relative air-fuel ratio was tuned to unity and the ignition timing was tuned for maximum engine torque. The experimental results indicated that the appropriate ethanol-gasoline mixing ratio can enhance engine torque output, especially at low engine speed. The brake thermal efficiency is maximum when the engine operates at 58-73% of WOT with an engine speed of 2000-2500 rpm, using E40 and E50 fuels. This paper also provides a guideline for a suitable ethanol-gasoline blend rate at a certain engine load and speed. (C) 2016 Elsevier Ltd. All rights reserved.