Search results for: executive control
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10851

Search results for: executive control

10371 Suppressing Vibration in a Three-axis Flexible Satellite: An Approach with Composite Control

Authors: Jalal Eddine Benmansour, Khouane Boulanoir, Nacera Bekhadda, Elhassen Benfriha

Abstract:

This paper introduces a novel composite control approach that addresses the challenge of stabilizing the three-axis attitude of a flexible satellite in the presence of vibrations caused by flexible appendages. The key contribution of this research lies in the development of a disturbance observer, which effectively observes and estimates the unwanted torques induced by the vibrations. By utilizing the estimated disturbance, the proposed approach enables efficient compensation for the detrimental effects of vibrations on the satellite system. To govern the attitude angles of the spacecraft, a proportional derivative controller (PD) is specifically designed and proposed. The PD controller ensures precise control over all attitude angles, facilitating stable and accurate spacecraft maneuvering. In order to demonstrate the global stability of the system, the Lyapunov method, a well-established technique in control theory, is employed. Through rigorous analysis, the Lyapunov method verifies the convergence of system dynamics, providing strong evidence of system stability. To evaluate the performance and efficacy of the proposed control algorithm, extensive simulations are conducted. The simulation results validate the effectiveness of the combined approach, showcasing significant improvements in the stabilization and control of the satellite's attitude, even in the presence of disruptive vibrations from flexible appendages. This novel composite control approach presented in this paper contributes to the advancement of satellite attitude control techniques, offering a promising solution for achieving enhanced stability and precision in challenging operational environments.

Keywords: attitude control, flexible satellite, vibration control, disturbance observer

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10370 Management Control Systems in Post-Incubation: An Investigation of Closed Down High-Technology Start-Ups

Authors: Jochen Edmund Kerschenbauer, Roman Salinger, Daniel Strametz

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Insufficient informal communication systems can lead to the first crisis (‘Crisis of Leadership’) for start-ups. Management Control Systems (MCS) are one way for high-technology start-ups to successfully overcome these problems. So far the literature has investigated the incubation of a start-up, but focused less on the post-incubation stage. This paper focuses on the use of MCS in post-incubation and, if failed start-ups agree, on how MCS are used. We conducted 14 semi-structured interviews for this purpose, to obtain our results. The overall conclusion is that the majority of the companies were closed down due to a combination of strategic, operative and financial reasons.

Keywords: closed down, high-technology, incubation, levers of control, management control systems, post-incubation, start-ups

Procedia PDF Downloads 1083
10369 Hybrid Control Mode Based on Multi-Sensor Information by Fuzzy Approach for Navigation Task of Autonomous Mobile Robot

Authors: Jonqlan Lin, C. Y. Tasi, K. H. Lin

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This paper addresses the issue of the autonomous mobile robot (AMR) navigation task based on the hybrid control modes. The novel hybrid control mode, based on multi-sensors information by using the fuzzy approach, has been presented in this research. The system operates in real time, is robust, enables the robot to operate with imprecise knowledge, and takes into account the physical limitations of the environment in which the robot moves, obtaining satisfactory responses for a large number of different situations. An experiment is simulated and carried out with a pioneer mobile robot. From the experimental results, the effectiveness and usefulness of the proposed AMR obstacle avoidance and navigation scheme are confirmed. The experimental results show the feasibility, and the control system has improved the navigation accuracy. The implementation of the controller is robust, has a low execution time, and allows an easy design and tuning of the fuzzy knowledge base.

Keywords: autonomous mobile robot, obstacle avoidance, MEMS, hybrid control mode, navigation control

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10368 The Interactions of Attentional Bias for Food, Trait Self-Control, and Motivation: A Model Testing Study

Authors: Hamish Love, Navjot Bhullar, Nicola Schutte

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Self-control and related psychological constructs have been shown to have a large role in the improvement and maintenance of healthful dietary behaviour. However, self-control for diet, and related constructs such as motivation, level of conflict between tempting desires and dietary goals, and attentional bias for tempting food, have not been studied together to establish their relationships, to the author’s best knowledge. Therefore the aim of this paper was to conduct model testing on these constructs and evaluate how they relate to affect dietary outcomes. 400 Australian adult participants will be recruited via the Qualtrics platform and will be representative across age and gender. They will complete survey and reaction timing surveys to gather data on the five target constructs: Trait Self-control, Attentional Bias for Food, Dietary Goal-Desire Incongruence, Motivation for Dietary Self-control, and Satisfaction with Dietary Behaviour. A model of moderated mediation is predicted, whereby the initial predictor (Dietary Goal-Desire Incongruence) predicts the level of the outcome variable, Satisfaction with Dietary Behaviour. We hypothesise that the relationship between these two variables will be mediated by Trait Self-Control and that the extent that Trait Self-control is allowed to mediate dietary outcome is moderated by both Attentional Bias for Food and Motivation for Dietary Self-control. The analysis will be conducted using the PROCESS module in SPSS 23. The results of model testing in this current study will be valuable to direct future research and inform which constructs could be important targets for intervention to improve dietary outcomes.

Keywords: self-control, diet, model testing, attentional bias, motivation

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10367 Adaptive Process Monitoring for Time-Varying Situations Using Statistical Learning Algorithms

Authors: Seulki Lee, Seoung Bum Kim

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Statistical process control (SPC) is a practical and effective method for quality control. The most important and widely used technique in SPC is a control chart. The main goal of a control chart is to detect any assignable changes that affect the quality output. Most conventional control charts, such as Hotelling’s T2 charts, are commonly based on the assumption that the quality characteristics follow a multivariate normal distribution. However, in modern complicated manufacturing systems, appropriate control chart techniques that can efficiently handle the nonnormal processes are required. To overcome the shortcomings of conventional control charts for nonnormal processes, several methods have been proposed to combine statistical learning algorithms and multivariate control charts. Statistical learning-based control charts, such as support vector data description (SVDD)-based charts, k-nearest neighbors-based charts, have proven their improved performance in nonnormal situations compared to that of the T2 chart. Beside the nonnormal property, time-varying operations are also quite common in real manufacturing fields because of various factors such as product and set-point changes, seasonal variations, catalyst degradation, and sensor drifting. However, traditional control charts cannot accommodate future condition changes of the process because they are formulated based on the data information recorded in the early stage of the process. In the present paper, we propose a SVDD algorithm-based control chart, which is capable of adaptively monitoring time-varying and nonnormal processes. We reformulated the SVDD algorithm into a time-adaptive SVDD algorithm by adding a weighting factor that reflects time-varying situations. Moreover, we defined the updating region for the efficient model-updating structure of the control chart. The proposed control chart simultaneously allows efficient model updates and timely detection of out-of-control signals. The effectiveness and applicability of the proposed chart were demonstrated through experiments with the simulated data and the real data from the metal frame process in mobile device manufacturing.

Keywords: multivariate control chart, nonparametric method, support vector data description, time-varying process

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10366 Assessment of the Work-Related Stress and Associated Factors among Sanitation Workers in Public Hospitals during COVID-19, Addis Ababa, Ethiopia

Authors: Zerubabel Mihret

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Background: Work-related stress is a pattern of reactions to work demands unmatched by worker’s knowledge, skills, or abilities. Healthcare institutions are considered high-risk and intensive work areas for work-related stress. However, there is the nonexistence of clear and strong data about the magnitude of work-related stress on sanitation workers in hospitals in Ethiopia. The aim of this study was to determine the magnitude of work-related stress among sanitation workers in public hospitals during COVID-19 in Addis Ababa, Ethiopia. Methods: Institution-based cross-sectional study was conducted from October 2021 to February 2022 among 494 sanitation workers who were selected from 4 hospitals. HSE (Health and Safety Executive of UK) standard data collection tool was used, and an interviewer-administered questionnaire was used to collect the data using KOBO collect application. The collected data were cleaned and analyzed using SPSS version 20.0. Both binary and multivariable logistic regression analyses were done to identify important factors having an association with work-related stress. Variables with p-value ≤ 0.25 in the bivariate analysis were entered into the multivariable logistic regression model. A statistically significant level was declared at a p-value ≤ 0.05. Results: This study revealed that the magnitude of work-related stress among sanitation workers was 49.2% (95% CI 45-54). Significant proportions (72.7%) of sanitation workers were dissatisfied with their current job. Sex, age, experience, and chewing khat were significantly associated with work-related stress. Conclusion: Work-related stress is significantly high among sanitation workers. Sex, age, experience, and chewing khat were identified as factors associated with work-related stress. Intervention program focusing on the prevention and control of stress is desired by hospitals.

Keywords: work-related stress, sanitation workers, Likert scale, public hospitals, Ethiopia

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10365 Assessment of Nurse's Knowledge Toward Infection Control for Wound Care in Governmental Hospital at Amran City-Yemen

Authors: Fares Mahdi

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Background: Infection control is an important concern for all health care professionals, especially nurses. Nurses have a higher risk for both self-acquiring and transmitting infections to other patients. Aim of this study: to assess nurses' knowledge regarding infection control for wound care. Methodology: a descriptive research design was used in the study. The total number studied sample was 200 nurses, were conducting in Amran Public Hospitals in Amran City- Yemen. The study covered sample nurses in the hospital according to the study population; a standard closed-ended questionnaire was used to collect the data. Results: The results showed less than half (37.5 %) of nurses were from 22 May Hospital, also followed by (62.5%) of them were from Maternal and Child Hospital. Also according to the department name. Most (22.5%) of nurses worked in an intensive care unit, followed by (20%) of them were working in the pediatric world, also about (19%) of them were working in the surgical department. While in finally, only about (8.5%) of them worked from another department. According to course training, The results showed about (21%) of nurses had course training in wound care management. At the same time, others (79%) of them have not had course training in wound care management. According to the total nurse's knowledge of infection control for wound care, that find more than two-thirds (68%) of nurses had fair knowledge according to total all of nurse's knowledge of infection control wound care. Conclusion:The results showed that more than two-thirds (68%) of nurses had fair knowledge according to total all of the nurse's knowledge of infection control for wound care. Recommendations: There should be providing training program about infection control masseurs and it's important for new employees of nurses. Providing continuing refreshment training courses about infection control programs and about evidence-based practice in infection control for all health care teams.

Keywords: assessment, knowledge, infection control, wound care, nurses, amran hospitals

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10364 Optimal Hybrid Linear and Nonlinear Control for a Quadcopter Drone

Authors: Xinhuang Wu, Yousef Sardahi

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A hybrid and optimal multi-loop control structure combining linear and nonlinear control algorithms are introduced in this paper to regulate the position of a quadcopter unmanned aerial vehicle (UAV) driven by four brushless DC motors. To this end, a nonlinear mathematical model of the UAV is derived and then linearized around one of its operating points. Using the nonlinear version of the model, a sliding mode control is used to derive the control laws of the motor thrust forces required to drive the UAV to a certain position. The linear model is used to design two controllers, XG-controller and YG-controller, responsible for calculating the required roll and pitch to maneuver the vehicle to the desired X and Y position. Three attitude controllers are designed to calculate the desired angular rates of rotors, assuming that the Euler angles are minimal. After that, a many-objective optimization problem involving 20 design parameters and ten objective functions is formulated and solved by HypE (Hypervolume estimation algorithm), one of the widely used many-objective optimization algorithms approaches. Both stability and performance constraints are imposed on the optimization problem. The optimization results in terms of Pareto sets and fronts are obtained and show that some of the design objectives are competing. That is, when one objective goes down, the other goes up. Also, Numerical simulations conducted on the nonlinear UAV model show that the proposed optimization method is quite effective.

Keywords: optimal control, many-objective optimization, sliding mode control, linear control, cascade controllers, UAV, drones

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10363 Design of Control System Based On PLC and Kingview for Granulation Product Line

Authors: Mei-Feng, Yude-Fan, Min-Zhu

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Based on PLC and kingview, this paper proposed a method that designed a set of the automatic control system according to the craft flow and demands for granulation product line. There were the main station and subordinate stations in PLC which were communicated by PROFIBUS network. PLC and computer were communicated by Ethernet network. The conversation function between human and machine was realized by kingview software, including actual time craft flows, historic report curves and product report forms. The construction of the control system, hardware collocation and software design were introduced. Besides these, PROFIBUS network frequency conversion control, the difficult points and configuration software design were elaborated. The running results showed that there were several advantages in the control system. They were high automatic degree, perfect function, perfect steady and convenient operation.

Keywords: PLC, PROFIBUS, configuration, frequency

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10362 Control of an Asymmetrical Design of a Pneumatically Actuated Ambidextrous Robot Hand

Authors: Emre Akyürek, Anthony Huynh, Tatiana Kalganova

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The Ambidextrous Robot Hand is a robotic device with the purpose to mimic either the gestures of a right or a left hand. The symmetrical behavior of its fingers allows them to bend in one way or another keeping a compliant and anthropomorphic shape. However, in addition to gestures they can reproduce on both sides, an asymmetrical mechanical design with a three tendons routing has been engineered to reduce the number of actuators. As a consequence, control algorithms must be adapted to drive efficiently the ambidextrous fingers from one position to another and to include grasping features. These movements are controlled by pneumatic muscles, which are nonlinear actuators. As their elasticity constantly varies when they are under actuation, the length of pneumatic muscles and the force they provide may differ for a same value of pressurized air. The control algorithms introduced in this paper take both the fingers asymmetrical design and the pneumatic muscles nonlinearity into account to permit an accurate control of the Ambidextrous Robot Hand. The finger motion is achieved by combining a classic PID controller with a phase plane switching control that turns the gain constants into dynamic values. The grasping ability is made possible because of a sliding mode control that makes the fingers adapt to the shape of an object before strengthening their positions.

Keywords: ambidextrous hand, intelligent algorithms, nonlinear actuators, pneumatic muscles, robotics, sliding control

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10361 An Attribute Based Access Control Model with POL Module for Dynamically Granting and Revoking Authorizations

Authors: Gang Liu, Huimin Song, Can Wang, Runnan Zhang, Lu Fang

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Currently, resource sharing and system security are critical issues. This paper proposes a POL module composed of PRIV ILEGE attribute (PA), obligation and log which improves attribute based access control (ABAC) model in dynamically granting authorizations and revoking authorizations. The following describes the new model termed PABAC in terms of the POL module structure, attribute definitions, policy formulation and authorization architecture, which demonstrate the advantages of it. The POL module addresses the problems which are not predicted before and not described by access control policy. It can be one of the subject attributes or resource attributes according to the practical application, which enhances the flexibility of the model compared with ABAC. A scenario that illustrates how this model is applied to the real world is provided.

Keywords: access control, attribute based access control, granting authorizations, privilege, revoking authorizations, system security

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10360 Fuzzy Logic for Control and Automatic Operation of Natural Ventilation in Buildings

Authors: Ekpeti Bukola Grace, Mahmoudi Sabar Esmail, Chaer Issa

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Global energy consumption has been increasing steadily over the last half - century, and this trend is projected to continue. As energy demand rises in many countries throughout the world due to population growth, natural ventilation in buildings has been identified as a viable option for lowering these demands, saving costs, and also lowering CO2 emissions. However, natural ventilation is driven by forces that are generally unpredictable in nature thus, it is important to manage the resulting airflow in order to maintain pleasant indoor conditions, making it a complex system that necessitates specific control approaches. The effective application of fuzzy logic technique amidst other intelligent systems is one of the best ways to bridge this gap, as its control dynamics relates more to human reasoning and linguistic descriptions. This article reviewed existing literature and presented practical solutions by applying fuzzy logic control with optimized techniques, selected input parameters, and expert rules to design a more effective control system. The control monitors used indoor temperature, outdoor temperature, carbon-dioxide levels, wind velocity, and rain as input variables to the system, while the output variable remains the control of window opening. This is achieved through the use of fuzzy logic control tool box in MATLAB and running simulations on SIMULINK to validate the effectiveness of the proposed system. Comparison analysis model via simulation is carried out, and with the data obtained, an improvement in control actions and energy savings was recorded.

Keywords: fuzzy logic, intelligent control systems, natural ventilation, optimization

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10359 The Mediator Role of Social Competence in the Relation between Effortful Control and Maths Achievement

Authors: M. A. Fernández-Vilar, M. D. Galián, E. Ato

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The aim of this work was to analyze the relation between children´s effortful control and Maths achievement in a sample of 447 Spanish children aged between 6 and 8 years. Traditionally, the literature confirms that higher level of effortful control has been associated with higher academic achievement, but there are few studies that include the effect that children´s social competence exert to this relation. To measure children’s effortful control parents were given the TMCQ (Temperament in Middle Childhood Questionnaire), and Maths achievement was taken from teacher´s rates. To measure social competence, we used the nominations method in the classroom context. Results confirmed that higher effortful control predicted a better maths achievement, whereas lower effortful control scores predicted lower Maths scores. Using a statistical modeling approach, we tested a mediation model that revealed the mediating role of social competence (popularity and rejection) in the relation between effortful control and Maths achievement. Concretely, higher social competence (higher popularity and lower rejection) seems to mediate the better Maths achievement showed by better self´regulated children. Therefore, an adequate social competence mediates the positive effect that self-regulatory capacity exerts to academic achievement. The clinical implications of the present findings should be considered. Specifically, rejected children must be detected and evaluated in community settings, such as school or community programs, due the relevant role of social competence in the relation between temperament and academic achievement.

Keywords: effortful control, maths achievement, social competence, mediation

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10358 Sliding Mode Position Control for Permanent Magnet Synchronous Motors Based on Passivity Approach

Authors: Jenn-Yih Chen, Bean-Yin Lee, Yuan-Chuan Hsu, Jui-Cheng Lin, Kuang-Chyi Lee

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In this paper, a sliding mode control method based on the passivity approach is proposed to control the position of surface-mounted permanent magnet synchronous motors (PMSMs). Firstly, the dynamics of a PMSM was proved to be strictly passive. The position controller with an adaptive law was used to estimate the load torque to eliminate the chattering effects associated with the conventional sliding mode controller. The stability analysis of the overall position control system was carried out by adopting the passivity theorem instead of Lyapunov-type arguments. Finally, experimental results were provided to show that the good position tracking can be obtained, and exhibit robustness in the variations of the motor parameters and load torque disturbances.

Keywords: adaptive law, passivity theorem, permanent magnet synchronous motor, sliding mode control

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10357 Optimal Tracking Control of a Hydroelectric Power Plant Incorporating Neural Forecasting for Uncertain Input Disturbances

Authors: Marlene Perez Villalpando, Kelly Joel Gurubel Tun

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In this paper, we propose an optimal control strategy for a hydroelectric power plant subject to input disturbances like meteorological phenomena. The engineering characteristics of the system are described by a nonlinear model. The random availability of renewable sources is predicted by a high-order neural network trained with an extended Kalman filter, whereas the power generation is regulated by the optimal control law. The main advantage of the system is the stabilization of the amount of power generated in the plant. A control supervisor maintains stability and availability in hydropower reservoirs water levels for power generation. The proposed approach demonstrated a good performance to stabilize the reservoir level and the power generation along their desired trajectories in the presence of disturbances.

Keywords: hydropower, high order neural network, Kalman filter, optimal control

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10356 A Comparative Study of Various Control Methods for Rendezvous of a Satellite Couple

Authors: Hasan Basaran, Emre Unal

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Formation flying of satellites is a mission that involves a relative position keeping of different satellites in the constellation. In this study, different control algorithms are compared with one another in terms of ΔV, velocity increment, and tracking error. Various control methods, covering continuous and impulsive approaches are implemented and tested for satellites flying in low Earth orbit. Feedback linearization, sliding mode control, and model predictive control are designed and compared with an impulsive feedback law, which is based on mean orbital elements. Feedback linearization and sliding mode control approaches have identical mathematical models that include second order Earth oblateness effects. The model predictive control, on the other hand, does not include any perturbations and assumes circular chief orbit. The comparison is done with 4 different initial errors and achieved with velocity increment, root mean square error, maximum steady state error, and settling time. It was observed that impulsive law consumed the least ΔV, while produced the highest maximum error in the steady state. The continuous control laws, however, consumed higher velocity increments and produced lower amounts of tracking errors. Finally, the inversely proportional relationship between tracking error and velocity increment was established.

Keywords: chief-deputy satellites, feedback linearization, follower-leader satellites, formation flight, fuel consumption, model predictive control, rendezvous, sliding mode

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10355 Examining the Modular End of Line Control Unit Design Criteria for Vehicle Sliding Door System Slide Profile

Authors: Orhan Kurtuluş, Cüneyt Yavuz

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The end of the line controls of the finished products in the automotive industry is important. The control that has been conducted with the manual methods for the sliding doors tracks is not sufficient and faulty products cannot be identified. As a result, the customer has the faulty products. In the scope of this study, the design criteria of the PLC integrated modular end of line control unit has been examined, designed and manufactured to make the control of the 10 different track profile to 2 different vehicles with an objective to minimize the salvage costs by obtaining more sensitive, certain and accurate measurement results. In the study that started with literature and patent review, the design inputs have been specified, the technical concept has been developed, computer supported mechanic design, control system and automation design, design review and design improvement have been made. Laser analog sensors at high sensitivity, probes and modular blocks have been used in the unit. The measurement has been conducted in the system and it is observed that measurement results are more sensitive than the previous methods.

Keywords: control unit design, end of line, modular design, sliding door system

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10354 Sliding Mode Controller for Active Suspension System on a Passenger Car Model

Authors: Nouby M. Ghazaly, Ahmed O. Moaaz, Mostafa Makrahy

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The main purpose of a car suspension system is to reduce the vibrations resulting from road roughness. The main objective of this research paper is to decrease vibration and improve passenger comfort through controlling car suspension system using sliding mode control techniques. The mathematical model for passive and active suspensions systems for quarter car model which subject to excitation from different road profiles is obtained. The active suspension system is synthesized based on sliding mode control for a quarter car model. The performance of the sliding mode control is determined through computer simulations using MATLAB and SIMULINK toolbox. The simulated results plotted in time domain, and root mean square values. It is found that active suspension system using sliding mode control improves the ride comfort and decrease vibration.

Keywords: quarter car model, active suspension system, sliding mode control, road profile

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10353 Neural Nets Based Approach for 2-Cells Power Converter Control

Authors: Kamel Laidi, Khelifa Benmansour, Ouahid Bouchhida

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Neural networks-based approach for 2-cells serial converter has been developed and implemented. The approach is based on a behavioural description of the different operating modes of the converter. Each operating mode represents a well-defined configuration, and for which is matched an operating zone satisfying given invariance conditions, depending on the capacitors' voltages and the load current of the converter. For each mode, a control vector whose components are the control signals to be applied to the converter switches has been associated. Therefore, the problem is reduced to a classification task of the different operating modes of the converter. The artificial neural nets-based approach, which constitutes a powerful tool for this kind of task, has been adopted and implemented. The application to a 2-cells chopper has allowed ensuring efficient and robust control of the load current and a high capacitors voltages balancing.

Keywords: neural nets, control, multicellular converters, 2-cells chopper

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10352 Design and Implementation of Embedded FM Transmission Control SW for Low Power Battery System

Authors: Young-Su Ryu, Kyung-Won Park, Jae-Hoon Song, Ki-Won Kwon

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In this paper, an embedded frequency modulation (FM) transmission control software (SW) for a low power battery system is designed and implemented. The simultaneous translation systems for various languages are needed as so many international conferences and festivals are held in world wide. Especially in portable transmitting and receiving systems, the ability of long operation life is used for a measure of value. This paper proposes an embedded FM transmission control SW for low power battery system and shows the results of the SW implemented on a portable FM transmission system.

Keywords: FM transmission, simultaneous translation system, portable transmitting and receiving systems, low power embedded control SW

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10351 Impact of Very Small Power Producers (VSPP) on Control and Protection System in Distribution Networks

Authors: Noppatee Sabpayakom, Somporn Sirisumrannukul

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Due to incentive policies to promote renewable energy and energy efficiency, high penetration levels of very small power producers (VSPP) located in distribution networks have imposed technical barriers and established new requirements for protection and control of the networks. Although VSPPs have economic and environmental benefit, they may introduce negative effects and cause several challenges on the issue of protection and control system. This paper presents comprehensive studies of possible impacts on control and protection systems based on real distribution systems located in a metropolitan area. A number of scenarios were examined primarily focusing on state of islanding, and un-disconnected VSPP during faults. It is shown that without proper measures to address the issues, the system would be unable to maintain its integrity of electricity power supply for disturbance incidents.

Keywords: control and protection systems, distributed generation, renewable energy, very small power producers

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10350 Artificial Neural Networks Controller for Power System Voltage Improvement

Authors: Sabir Messalti, Bilal Boudjellal, Azouz Said

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In this paper, power system Voltage improvement using wind turbine is presented. Two controllers are used: a PI controller and Artificial Neural Networks (ANN) controllers are studied to control of the power flow exchanged between the wind turbine and the power system in order to improve the bus voltage. The wind turbine is based on a doubly-fed induction generator (DFIG) controlled by field-oriented control. Indirect control is used to control of the reactive power flow exchanged between the DFIG and the power system. The proposed controllers are tested on power system for large voltage disturbances.

Keywords: artificial neural networks controller, DFIG, field-oriented control, PI controller, power system voltage improvement

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10349 Model-Free Distributed Control of Dynamical Systems

Authors: Javad Khazaei, Rick Blum

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Distributed control is an efficient and flexible approach for coordination of multi-agent systems. One of the main challenges in designing a distributed controller is identifying the governing dynamics of the dynamical systems. Data-driven system identification is currently undergoing a revolution. With the availability of high-fidelity measurements and historical data, model-free identification of dynamical systems can facilitate the control design without tedious modeling of high-dimensional and/or nonlinear systems. This paper develops a distributed control design using consensus theory for linear and nonlinear dynamical systems using sparse identification of system dynamics. Compared with existing consensus designs that heavily rely on knowing the detailed system dynamics, the proposed model-free design can accurately capture the dynamics of the system with available measurements and input data and provide guaranteed performance in consensus and tracking problems. Heterogeneous damped oscillators are chosen as examples of dynamical system for validation purposes.

Keywords: consensus tracking, distributed control, model-free control, sparse identification of dynamical systems

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10348 Potentiality of a Community of Practice between Public Schools and the Private Sector for Integrating Sustainable Development into the School Curriculum

Authors: Aiydh Aljeddani, Fran Martin

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The critical time in which we live requires rethinking of many potential ways in order to make the concept of sustainability and its principles an integral part of our daily life. One of these potential approaches is how to attract community institutions, such as the private sector, to participate effectively in the sustainability industry by supporting public schools to fulfill their duties. A collaborative community of practice can support this purpose and can provide a flexible framework, which allows the members of the community to participate effectively. This study, conducted in Saudi Arabia, aimed to understand the process of a collaborative community of practice of involving the private sector as a member of this community to integrate the sustainability concept in school activities and projects. This study employed a qualitative methodology to understand this authentic and complex phenomenon. A case study approach, ethnography and some elements of action research were followed in this study. The methods of unstructured interviews, artifacts, observation, and teachers’ field notes were used to collect the data. The participants were three secondary teachers, twelve chief executive officers, and one school administrative officer. Certain contextual conditions, as shown by the data, should be taken into consideration when policy makers and school administrations in Saudi Arabia desire to integrate sustainability into school activities. The first of these was the acknowledgement of the valuable role of the members’ personality, efforts, abilities, and experiences, which played vital roles in integrating sustainability. Second, institutional culture, which was not expected to emerge as an important factor in this study, has a significant role in the integration of sustainability. Credibility among the members of the community towards the integration of the sustainability concept and its principles through school activities is another important condition. Fourth, some chief executive officers’ understanding of Corporate Social Responsibility (CSR) towards contribution to sustainability agenda was shallow and limited and this could impede the successful integration of sustainability. Fifth, a shared understanding between the members of the community about integrating sustainability was a vital condition in the integration process. The study also revealed that the integration of sustainability could not be an ongoing process if implemented in isolation of the other community institutions such as the private sector. The study finally offers a number of recommendations to improve on the current practices and suggests areas for further studies.

Keywords: community of practice, public schools, private sector, sustainable development

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10347 Safe and Efficient Deep Reinforcement Learning Control Model: A Hydroponics Case Study

Authors: Almutasim Billa A. Alanazi, Hal S. Tharp

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Safe performance and efficient energy consumption are essential factors for designing a control system. This paper presents a reinforcement learning (RL) model that can be applied to control applications to improve safety and reduce energy consumption. As hardware constraints and environmental disturbances are imprecise and unpredictable, conventional control methods may not always be effective in optimizing control designs. However, RL has demonstrated its value in several artificial intelligence (AI) applications, especially in the field of control systems. The proposed model intelligently monitors a system's success by observing the rewards from the environment, with positive rewards counting as a success when the controlled reference is within the desired operating zone. Thus, the model can determine whether the system is safe to continue operating based on the designer/user specifications, which can be adjusted as needed. Additionally, the controller keeps track of energy consumption to improve energy efficiency by enabling the idle mode when the controlled reference is within the desired operating zone, thus reducing the system energy consumption during the controlling operation. Water temperature control for a hydroponic system is taken as a case study for the RL model, adjusting the variance of disturbances to show the model’s robustness and efficiency. On average, the model showed safety improvement by up to 15% and energy efficiency improvements by 35%- 40% compared to a traditional RL model.

Keywords: control system, hydroponics, machine learning, reinforcement learning

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10346 Experimental Implementation of Model Predictive Control for Permanent Magnet Synchronous Motor

Authors: Abdelsalam A. Ahmed

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Fast speed drives for Permanent Magnet Synchronous Motor (PMSM) is a crucial performance for the electric traction systems. In this paper, PMSM is drived with a Model-based Predictive Control (MPC) technique. Fast speed tracking is achieved through optimization of the DC source utilization using MPC. The technique is based on predicting the optimum voltage vector applied to the driver. Control technique is investigated by comparing to the cascaded PI control based on Space Vector Pulse Width Modulation (SVPWM). MPC and SVPWM-based FOC are implemented with the TMS320F2812 DSP and its power driver circuits. The designed MPC for a PMSM drive is experimentally validated on a laboratory test bench. The performances are compared with those obtained by a conventional PI-based system in order to highlight the improvements, especially regarding speed tracking response.

Keywords: permanent magnet synchronous motor, model-based predictive control, DC source utilization, cascaded PI control, space vector pulse width modulation, TMS320F2812 DSP

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10345 Seismic Resistant Mechanism of Two-by-four Wooden Frame with Vibration Control Device

Authors: Takumi Ito, Kurumi Kurokawa, Dong Hang Wu, Takashi Nagumo, Haruhiko Hirata

Abstract:

The structural system of wooden house by two-by-four method is widely adopted in any countries, and a various type of vibration control system for building structures has been developed on country with frequent earthquake. In this study, a vibration control device called “Scaling Frame” (SF) is suggested, and which is applied to wooden two-by-four method structures. This paper performs the experimental study to investigate the restoring force characteristics of two-by-four with SF device installed. The seismic resistant performance is estimated experimentally, and also the applicability and effectiveness are discussing.

Keywords: two-by-four method, seismic vibration control, horizontally loading test, restoring force characteristics

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10344 The Determinants of Corporate Social Responsibility Disclosure Extent and Quality: The Case of Jordan

Authors: Hani Alkayed, Belal Omar, Eileen Roddy

Abstract:

This study focuses on investigating the determinants of Corporate Social Responsibility Disclosure (CSRD) extent and quality in Jordan. The study examines factors that influence CSR disclosure extent and quality, such as corporate characteristics (size, gearing, firm’s age, and industry type), corporate governance (board size, number of meetings, non-executive directors, female directors in the board, family directors in the board, foreign members, audit committee, type of external auditors, and CEO duality) and ownership structure (government ownership, institutional ownership, and ownership concentration). Legitimacy theory is utilised as the main theory for our theoretical framework. A quantitative approach is adopted for this research and content analysis technique is used to gather CSR disclosure extent and quality from the annual reports. The sample is withdrawn from the annual reports of 118 Jordanian companies over the period of 2010-2015. A CSRD index is constructed, and includes the disclosures of the following categories; environmental, human resources, product and consumers, and community involvement. A 7 point-scale measurement was developed to examine the quality of disclosure, were 0= No Disclosures, 1= General disclosures, (Non-monetary), 2= General disclosures, (Non-monetary) with pictures, charts, and graphs 3= Descriptive/ qualitative disclosures, specific details (Non-monetary), 4= Descriptive/ qualitative disclosures, specific details with pictures, charts, and graphs, 5= Numeric disclosures, full descriptions with supporting numbers, 6= Numeric disclosures, full descriptions with supporting numbers, pictures, and Charts. This study fills the gap in the literature regarding CSRD in Jordan, and the fact that all the previous studies have ignored a clear categorisation as a measurement of quality. The result shows that the extent of CSRD is higher than the quality in Jordan. Regarding the determinants of CSR disclosures, the followings were found to have a significant relationship with both extent and quality of CSRD except non-executives, were the significant relationship was found just with the extent of CSRD: board size, non-executive directors, firm’s age, foreign members on the board, number of boards meetings, the presence of audit committees, big 4, government ownership, firm’s size, industry type.

Keywords: content analysis, corporate governance, corporate social responsibility disclosure, Jordan, quality of disclosure

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10343 Proposal for a Web System for the Control of Fungal Diseases in Grapes in Fruits Markets

Authors: Carlos Tarmeño Noriega, Igor Aguilar Alonso

Abstract:

Fungal diseases are common in vineyards; they cause a decrease in the quality of the products that can be sold, generating distrust of the customer towards the seller when buying fruit. Currently, technology allows the classification of fruits according to their characteristics thanks to artificial intelligence. This study proposes the implementation of a control system that allows the identification of the main fungal diseases present in the Italia grape, making use of a convolutional neural network (CNN), OpenCV, and TensorFlow. The methodology used was based on a collection of 20 articles referring to the proposed research on quality control, classification, and recognition of fruits through artificial vision techniques.

Keywords: computer vision, convolutional neural networks, quality control, fruit market, OpenCV, TensorFlow

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10342 Use of Smartwatches for the Emotional Self-Regulation of Individuals with Autism Spectrum Disorder (ASD)

Authors: Juan C. Torrado, Javier Gomez, Guadalupe Montero, German Montoro, M. Dolores Villalba

Abstract:

One of the most challenging aspects of the executive dysfunction of people with Autism Spectrum Disorders is the behavior control. This is related to a deficit in their ability to regulate, recognize and manage their own emotions. Some researchers have developed applications for tablets and smartphones to practice strategies of relaxation and emotion recognition. However, they cannot be applied to the very moment of temper outbursts, anger episodes or anxiety, since they require to carry the device, start the application and be helped by caretakers. Also, some of these systems are developed for either obsolete technologies (old versions of tablet devices, PDAs, outdated operative systems of smartphones) or specific devices (self-developed or proprietary ones) that create differentiation between the users and the rest of the individuals in their context. For this project we selected smartwatches. Focusing on emergent technologies ensures a wide lifespan of the developed products, because the derived products are intended to be available in the same moment the very technology gets popularized, not later. We also focused our research in commercial versions of smartwatches, since this way differentiation is easily avoided, so the users’ abandonment rate lowers. We have developed a smartwatch system along with a smartphone authoring tool to display self-regulation strategies. These micro-prompting strategies are conformed of pictograms, animations and temporizers, and they are designed by means of the authoring tool: When both devices synchronize their data, the smartwatch holds the self-regulation strategies, which are triggered when the smartwatch sensors detect a remarkable rise of heart rate and movement. The system is being currently tested in an educational center of people with ASD of Madrid, Spain.

Keywords: assistive technologies, emotion regulation, human-computer interaction, smartwatches

Procedia PDF Downloads 285