Search results for: Knowledge-based Supplementary Control
2882 Control Analysis Using Tuning Methods for a Designed, Developed and Modeled Cross Flow Water Tube Heat Exchanger
Authors: Shaival H. Nagarsheth, Utpal Pandya, Hemant J. Nagarsheth
Abstract:
Cross flow water tube heat exchanger can be designed and made operational using methods of model building and simulation of the system. This paper projects the design and development of a model of cross flow water tube heat-exchanger system, simulation and validation of control analysis of different tuning methods. Feedback and override control system is developed using inputs acquired with the help of sensory system. A mathematical model is formulated for analysis of system behaviour. The temperature is regulated at the desired set point automatically.
Keywords: Heat Exchanger, Feedback, Override, Temperature, PID.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 23982881 Analysis and Simulation of Automotive Interleaved Buck Converter
Authors: Mohamed. A. Shrud, Ahmad H. Kharaz, Ahmed. S. Ashur, Ahmed Faris, Mustafa Benamar
Abstract:
This paper will focus on modeling, analysis and simulation of a 42V/14V dc/dc converter based architecture. This architecture is considered to be technically a viable solution for automotive dual-voltage power system for passenger car in the near further. An interleaved dc/dc converter system is chosen for the automotive converter topology due to its advantages regarding filter reduction, dynamic response, and power management. Presented herein, is a model based on one kilowatt interleaved six-phase buck converter designed to operate in a Discontinuous Conduction Mode (DCM). The control strategy of the converter is based on a voltagemode- controlled Pulse Width Modulation (PWM) with a Proportional-Integral-Derivative (PID). The effectiveness of the interleaved step-down converter is verified through simulation results using control-oriented simulator, MatLab/Simulink.
Keywords: Automotive, dc-to-dc power modules, design, interleaved, Matlab\Simulink and PID control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 42152880 Steady-State Analysis and Control of Double Feed Induction Motor
Authors: H. Sediki, Dj. Ould Abdeslam, T. Otmane-cherif, A. Bechouche, K. Mesbah
Abstract:
This paper explores steady-state characteristics of grid-connected doubly fed induction motor (DFIM) in case of unity power factor operation. Based on the synchronized mathematical model, analytic determination of the control laws is presented and illustrated by various figures to understand the effect of the applied rotor voltage on the speed and the active power. On other hand, unlike previous works where the stator resistance was neglected, in this work, stator resistance is included such that the equations can be applied to small wind turbine generators which are becoming more popular. Finally the work is crowned by integration of the studied induction generator in a wind system where an open loop control is proposed confers a remarkable simplicity of implementation compared to the known methods.Keywords: DFIM, equivalent circuit, induction machine, steady state
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19382879 Sensory Characterization of Cookies with Chestnut Flour
Authors: Ljubica Dokić, Ivana Nikolić, Dragana Šoronja–Simović, Biljana Pajin, Nils Juul
Abstract:
In this work sensory characteristics of cookies with different amount of chestnut flour were determined by sensory and instrumental methods. The wheat flour for cookies was substituted with chestnut flour in three different levels (20, 40 and 60%) and the dough moisture was 22%. The control sample was with 100% of wheat flour. Sensory quality of the cookies was described using quantity descriptive method (QDA) by six trained members of descriptive panel. Instrumental evaluation included texture characterization by texture analyzer, the color measurements (CIE L*a*b* system) and determination by videometer.
The samples with 20% of chestnut flour were with highest ponderated score for overall sensory impression (17.6), which is very close to score for control sample (18). Increase in amount of chestnut flour caused decrease in scores for all sensory properties, thus overall sensory score decreased also. Compared to control sample and with increase in amount of chestnut flour, instrumental determination of the samples confirmed the sensory analysis results. The hardness of the cookies increased, as well as the values of red a* and yellow (b*) component coordinate, but the values for lightness (L*) decreased. Also the values, evaluated by videometer at defined wavelength, were the highest for control cookies and decreased with increase in amount of chestnut flour.
Keywords: Cookies, chestnut flour, sensory characteristics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 28032878 Ways for the Development of the Audit Quality Control System through the Analysis of Ongoing Problems, Experience and Challenges: Example of the Republic of Georgia
Authors: Levan Sabauri
Abstract:
Audit is an independent inspection of the financial statement of the audited person and expresses the opinion of an auditor on the reliability of this statement. The auditor’s activity (auditor’s service) is realized by auditing organizations, individual auditors in connection to conduction of an audit and rendering of audit accompanying services. The profession of auditor means a high level of responsibility for rendered service. Results of decisions made by information users depend on the quality of the auditor’s conclusion. Owners, investors, creditors, and society rely on the opinion of the auditor under the condition that inspection was conducted with good quality. Therefore, the existence of the well-functioning audit quality control system for the administering of the audit is an important issue. An efficient audit quality control system is a substantial challenge that many countries face worldwide, especially those states where these systems are being formed within the respective reform program. The presented article reflects on the best practices of the leading countries, the assumptions and recommendations for the financial accounting, reporting and audit; current reforms in Georgia are made based on this comparative analysis.
Keywords: Audit quality control, audit program, financial statement, perspective analysis.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 6822877 H∞ Takagi-Sugeno Fuzzy State-Derivative Feedback Control Design for Nonlinear Dynamic Systems
Authors: N. Kaewpraek, W. Assawinchaichote
Abstract:
This paper considers an H∞ TS fuzzy state-derivative feedback controller for a class of nonlinear dynamical systems. A Takagi-Sugeno (TS) fuzzy model is used to approximate a class of nonlinear dynamical systems. Then, based on a linear matrix inequality (LMI) approach, we design an H∞ TS fuzzy state-derivative feedback control law which guarantees L2-gain of the mapping from the exogenous input noise to the regulated output to be less or equal to a prescribed value. We derive a sufficient condition such that the system with the fuzzy controller is asymptotically stable and H∞ performance is satisfied. Finally, we provide and simulate a numerical example is provided to illustrate the stability and the effectiveness of the proposed controller.Keywords: H∞ fuzzy control, LMI, Takagi-Sugano (TS) fuzzy model, nonlinear dynamic systems, state-derivative feedback.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9292876 The Control of a Highly Nonlinear Two-wheels Balancing Robot: A Comparative Assessment between LQR and PID-PID Control Schemes
Authors: A. N. K. Nasir, M. A. Ahmad, R. M. T. Raja Ismail
Abstract:
The research on two-wheels balancing robot has gained momentum due to their functionality and reliability when completing certain tasks. This paper presents investigations into the performance comparison of Linear Quadratic Regulator (LQR) and PID-PID controllers for a highly nonlinear 2–wheels balancing robot. The mathematical model of 2-wheels balancing robot that is highly nonlinear is derived. The final model is then represented in statespace form and the system suffers from mismatched condition. Two system responses namely the robot position and robot angular position are obtained. The performances of the LQR and PID-PID controllers are examined in terms of input tracking and disturbances rejection capability. Simulation results of the responses of the nonlinear 2–wheels balancing robot are presented in time domain. A comparative assessment of both control schemes to the system performance is presented and discussed.Keywords: PID, LQR, Two-wheels balancing robot.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 52512875 Significant Role Analysis of Transmission Control Protocols in 4G Cellular Systems
Authors: Ghassan A. Abed, Bayan M. Sabbar
Abstract:
The society of 3rd Generation Partnership Project (3GPP) is completed developing Long Term Evolution Advanced (LTE-Advanced) systems as a standard 4G cellular system. This generation goals to produce conditions for a new radio-access technology geared to higher data rates, low latency, and better spectral efficiency. LTE-Advanced is an evolutionary step in the continuing development of LTE where the description in this article is based on LTE release 10. This paper provides a model of the traffic links of 4G system represented by LTE-Advanced system with the effect of the Transmission Control Protocols (TCP) and Stream Control Transmission Protocol (SCTP) in term of throughput and packet loss. Furthermore, the article presents the investigation and the analysis the behavior of SCTP and TCP variants over the 4G cellular systems. The traffic model and the scenario of the simulation developed using the network simulator NS-2 using different TCP source variants.
Keywords: LTE-Advanced, LTE, SCTP, TCP, 4G, NS-2.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19322874 Optimal Efficiency Control of Pulse Width Modulation - Inverter Fed Motor Pump Drive Using Neural Network
Authors: O. S. Ebrahim, M. A. Badr, A. S. Elgendy, K. O. Shawky, P. K. Jain
Abstract:
This paper demonstrates an improved Loss Model Control (LMC) for a 3-phase induction motor (IM) driving pump load. Compared with other power loss reduction algorithms for IM, the presented one has the advantages of fast and smooth flux adaptation, high accuracy, and versatile implementation. The performance of LMC depends mainly on the accuracy of modeling the motor drive and losses. A loss-model for IM drive that considers the surplus power loss caused by inverter voltage harmonics using closed-form equations and also includes the magnetic saturation has been developed. Further, an Artificial Neural Network (ANN) controller is synthesized and trained offline to determine the optimal flux level that achieves maximum drive efficiency. The drive’s voltage and speed control loops are connecting via the stator frequency to avoid the possibility of excessive magnetization. Besides, the resistance change due to temperature is considered by a first-order thermal model. The obtained thermal information enhances motor protection and control. These together have the potential of making the proposed algorithm reliable. Simulation and experimental studies are performed on 5.5 kW test motor using the proposed control method. The test results are provided and compared with the fixed flux operation to validate the effectiveness.
Keywords: Artificial neural network, ANN, efficiency optimization, induction motor, IM, Pulse Width Modulated, PWM, harmonic losses.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3272873 The Virtual Container Yard: Identifying the Persuasive Factors in Container Interchange
Authors: L. Edirisinghe, Zhihong Jin, A. W. Wijeratne, R. Mudunkotuwa
Abstract:
The virtual container yard is an effective solution to the container inventory imbalance problem which is a global issue. It causes substantial cost to carriers, which inadvertently adds to the prices of consumer goods. The virtual container yard is rooted in the fundamentals of container interchange between carriers. If carriers opt to interchange their excess containers with those who are deficit, a substantial part of the empty reposition cost could be eliminated. Unlike in other types of ships, cargo cannot be directly loaded to a container ship. Slots and containers are supplementary components; thus, without containers, a carrier cannot ship cargo if the containers are not available and vice versa. Few decades ago, carriers recognized slot (the unit of space in a container ship) interchange as a viable solution for the imbalance of shipping space. Carriers interchange slots among them and it also increases the advantage of scale of economies in container shipping. Some of these service agreements between mega carriers have provisions to interchange containers too. However, the interchange mechanism is still not popular among carriers for containers. This is the paradox that prevails in the liner shipping industry. At present, carriers reposition their excess empty containers to areas where they are in demand. This research applied factor analysis statistical method. The paper reveals that five major components may influence the virtual container yard namely organisation, practice and culture, legal and environment, international nature, and marketing. There are 12 variables that may impact the virtual container yard, and these are explained in the paper.
Keywords: Virtual container yard, imbalance, management, inventory.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8222872 The Hybrid Dimming Control System for Solar Charging Robot
Authors: A. Won-Yong Chae, B. Hyung-Nam Kim, C. Kyoung-Jun Lee, D. Hee-Je Kim
Abstract:
The renewable energy has been attracting attention as a new alternative energy due to the problem of environmental pollution and resource depletion. In particular, daylighting and PV system are regarded as the solutions. In this paper, the hybrid dimming control system supplied by solar cell and daylighting system was designed. Daylighting system is main source and PV system is spare source. PV system operates the LED lamp which supports daylighting system because daylighting system is unstable due to the variation of irradiance. In addition, PV system has a role charging batteries. Battery charging has a benefit that PV system operate LED lamp in the bad weather. However, LED lamp always can`t turn on that-s why dimming control system was designed. In particular, the solar charging robot was designed to check the interior irradiance intensity. These systems and the application of the solar charging robot are expected to contribute developing alternative energy in the near future.Keywords: Daylighting system, PV system, LED lamp, Suntracking robot.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17912871 Evaluation of drought Tolerance Indices in Dryland Bread wheat Genotypes under Post-Anthesis drought Stress
Authors: Mokhtar Ghobadi , Mohammad-Eghbal Ghobadi, Danial Kahrizi, Alireza Zebarjadi, Mahdi Geravandi
Abstract:
Post-anthesis drought stress is the most important problem affecting wheat production in dryland fields, specially in Mediterranean regions. The main objective of this research was to evaluate drought tolerance indices in dryland wheat genotypes under post-anthesis drought stress. The research was including two different experiments. In each experiment, twenty dryland bread wheat genotypes were sown in a randomized complete blocks design (RCBD) with three replications. One of experiments belonged to rain-fed conditions (post-anthesis drought stress) and other experiment was under non-stress conditions (with supplemental irrigation). Different drought tolerance indices include Stress Tolerance (Tol), Mean Productivity (MP), Geometric Mean Productivity (GMP), Stress Susceptibility Index (SSI), Stress Tolerance Index (STI), Harmonic Mean (HAM), Yield Index (YI) and Yield Stability Index (YSI) were evaluate based on grain yield under rain-fed (Ys) and supplemental irrigation (Yp) environments. G10 and G12 were the most tolerant genotypes based on TOL and SSI. But, based on MP, GMP, STI, HAM and YI indices, G1 and G2 were selected. STI, GMP and MP indices had high correlation with grain yield under rain-fed and supplementary irrigation conditions and were recognized as appropriate indices to identify genotypes with high grain yield and low sensitivity to drought stress environments.Keywords: Dryland wheat, Supplemental irrigation, Tolerance indices
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20392870 A Posterior Predictive Model-Based Control Chart for Monitoring Healthcare
Authors: Yi-Fan Lin, Peter P. Howley, Frank A. Tuyl
Abstract:
Quality measurement and reporting systems are used in healthcare internationally. In Australia, the Australian Council on Healthcare Standards records and reports hundreds of clinical indicators (CIs) nationally across the healthcare system. These CIs are measures of performance in the clinical setting, and are used as a screening tool to help assess whether a standard of care is being met. Existing analysis and reporting of these CIs incorporate Bayesian methods to address sampling variation; however, such assessments are retrospective in nature, reporting upon the previous six or twelve months of data. The use of Bayesian methods within statistical process control for monitoring systems is an important pursuit to support more timely decision-making. Our research has developed and assessed a new graphical monitoring tool, similar to a control chart, based on the beta-binomial posterior predictive (BBPP) distribution to facilitate the real-time assessment of health care organizational performance via CIs. The BBPP charts have been compared with the traditional Bernoulli CUSUM (BC) chart by simulation. The more traditional “central” and “highest posterior density” (HPD) interval approaches were each considered to define the limits, and the multiple charts were compared via in-control and out-of-control average run lengths (ARLs), assuming that the parameter representing the underlying CI rate (proportion of cases with an event of interest) required estimation. Preliminary results have identified that the BBPP chart with HPD-based control limits provides better out-of-control run length performance than the central interval-based and BC charts. Further, the BC chart’s performance may be improved by using Bayesian parameter estimation of the underlying CI rate.
Keywords: Average run length, Bernoulli CUSUM chart, beta binomial posterior predictive distribution, clinical indicator, health care organization, highest posterior density interval.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8562869 Fuel Economy and Stability Enhancement of the Hybrid Vehicles by Using Electrical Machines on Non-Driven Wheels
Authors: P. Naderi, S.M.T. Bathaee, R. Hoseinnezhad, R. Chini
Abstract:
Using electrical machine in conventional vehicles, also called hybrid vehicles, has become a promising control scheme that enables some manners for fuel economy and driver assist for better stability. In this paper, vehicle stability control, fuel economy and Driving/Regeneration braking for a 4WD hybrid vehicle is investigated by using an electrical machine on each non-driven wheels. In front wheels driven vehicles, fuel economy and regenerative braking can be obtained by summing torques applied on rear wheels. On the other hand, unequal torques applied to rear wheels provides enhanced safety and path correction in steering. In this paper, a model with fourteen degrees of freedom is considered for vehicle body, tires and, suspension systems. Thereafter, powertrain subsystems are modeled. Considering an electrical machine on each rear wheel, a fuzzy controller is designed for each driving, braking, and stability conditions. Another fuzzy controller recognizes the vehicle requirements between the driving/regeneration and stability modes. Intelligent vehicle control to multi objective operation and forward simulation are the paper advantages. For reaching to these aims, power management control and yaw moment control will be done by three fuzzy controllers. Also, the above mentioned goals are weighted by another fuzzy sub-controller base on vehicle dynamic. Finally, Simulations performed in MATLAB/SIMULINK environment show that the proposed structure can enhance the vehicle performance in different modes effectively.
Keywords: Hybrid, pitch, roll, regeneration, yaw.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18592868 PR Current Control with Harmonic Compensation in Grid Connected PV Inverters
Authors: Daniel Zammit, Cyril Spiteri Staines, Maurice Apap
Abstract:
This paper presents a study on Proportional Resonant (PR) current control with additional PR harmonic compensators for Grid Connected Photovoltaic (PV) Inverters. Both simulation and experimental results will be presented. Testing was carried out on a 3kW Grid-Connected PV Inverter which was designed and constructed for this research.
Keywords: Inverters, Proportional-Resonant Controllers, Harmonic Compensation, Photovoltaic.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 33802867 Speed Sensorless Control with a Linearizationby State Feedback of Asynchronous Machine Using a Model Reference Adaptive System
Authors: A. Larabi, M. S. Boucherit
Abstract:
In this paper, we show that the association of the PI regulators for the speed and stator currents with a control strategy using the linearization by state feedback for an induction machine without speed sensor, and with an adaptation of the rotor resistance. The rotor speed is estimated by using the model reference adaptive system approach (MRAS). This method consists of using two models: The first is the reference model and the second is an adjustable one in which two components of the stator flux, obtained from the measurement of the currents and stator voltages are estimated. The estimated rotor speed is then obtained by canceling the difference between stator-flux of the reference model and those of the adjustable one. Satisfactory results of simulation are obtained and discussed in this paper to highlight the proposed approach.Keywords: Asynchronous actuator, PI Regulator, adaptivemethod with reference model, Vector control.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 11042866 Application of the Transtheoretical Model of Exercise Behavior Change Plan in High School Students
Authors: Frank C. Pan, Chih-Hao Chen
Abstract:
The purpose of this study is to discuss the effect of the intervention of exercise behavior change plan for high school students on study subjects- social and psychological factors and exercise stages. This research uses the transtheoretical model as the research framework. One experiment group and one control group were used in a quasi-experimental design research. The experimental group accepted health-related physical fitness course and the traditional course; the control group accepted traditional physical education course. There is a significant difference before and after the intervention in the experimental group. Karl-s test shows the experimental group gained a better improvement than that in the control group. The Analysis of Covariance had shown the exercise stages (F=7.62, p<0.05), and the perceived exercise benefit (F=16.91, p<0.05) of the experimental group were obviously larger than those of the control group. There was no major effect on the perceived exercise barrier (F=0.61, p>0.05) after the intervention of exercise behavior change plan. However, the rate of high school students the practical implementation of the exercise is not high, obviously influenced by the exercise barrier. The academic and examination pressure may be the major causes of the exercise barrier in the high school.Keywords: Transtheoretical model (TTM), High school students, exercise behavior
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 39582865 Multipurpose Agricultural Robot Platform: Conceptual Design of Control System Software for Autonomous Driving and Agricultural Operations Using Programmable Logic Controller
Authors: P. Abhishesh, B. S. Ryuh, Y. S. Oh, H. J. Moon, R. Akanksha
Abstract:
This paper discusses about the conceptual design and development of the control system software using Programmable logic controller (PLC) for autonomous driving and agricultural operations of Multipurpose Agricultural Robot Platform (MARP). Based on given initial conditions by field analysis and desired agricultural operations, the structural design development of MARP is done using modelling and analysis tool. PLC, being robust and easy to use, has been used to design the autonomous control system of robot platform for desired parameters. The robot is capable of performing autonomous driving and three automatic agricultural operations, viz. hilling, mulching, and sowing of seeds in the respective order. The input received from various sensors on the field is later transmitted to the controller via ZigBee network to make the changes in the control program to get desired field output. The research is conducted to provide assistance to farmers by reducing labor hours for agricultural activities by implementing automation. This study will provide an alternative to the existing systems with machineries attached behind tractors and rigorous manual operations on agricultural field at effective cost.
Keywords: Agricultural operations, autonomous driving, MARP, PLC.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21762864 Numerical Simulation and Experiment of a Lifting Body with Leading-Edge Rotating Cylinder
Authors: A. Badarudin, C. S. Oon, S. N. Kazi, N. Nik-Ghazali, Y. J. Lee, W. T. Chong
Abstract:
An experimental and simulation flight test has been carried out to evaluate the longitudinal gliding characteristics of a lifting body with blunted half-cone geometry. The novelty here is the lifting body's pitch control mechanism, which consists of a pair of leading-edge rotating cylinders. Flight simulation uses aerodynamic data from computational fluid dynamics supported by wind-tunnel test. Flight test consists of releasing an aluminum lifting body model from a moving vehicle at the appropriate wind speed while measuring the lifting body's variation of altitude against time of flight. Results show that leading-edge rotating cylinder is able to give small amounts of improvement to the longitudinal stability and pitch control to the lifting body.
Keywords: Lifting body, pitch control, aerodynamic, rotating cylinder.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19182863 Distributed Motion Control Real-Time Contouring Algorithm Implementation and Performance Test
Authors: Francisco J. Lopez-Jaquez, Sandra E. Ramirez-Jara
Abstract:
This paper presents an implementation and performance test of a distributed motion control system based on a master-slave configuration used to move a plasma-cutting torch over a predefined trajectory. The master is a general-purpose computer running on an open source operating system platform and software developer. Software running in the master computer generates commands on real time and we measure performance based on a selected set of differences between expected and observed distances. We are testing the null hypothesis that the outcome trajectory is identical to the input against the alternative hypothesis that there is a shift to the right or left of the input one. We used the Wilcoxon signed ranks test method for the hypothesis test.
Keywords: Distributed, motion, control, real-time, contouring.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14802862 Conservativeness of Probabilistic Constrained Optimal Control Method for Unknown Probability Distribution
Authors: Tomoaki Hashimoto
Abstract:
In recent decades, probabilistic constrained optimal control problems have attracted much attention in many research fields. Although probabilistic constraints are generally intractable in an optimization problem, several tractable methods haven been proposed to handle probabilistic constraints. In most methods, probabilistic constraints are reduced to deterministic constraints that are tractable in an optimization problem. However, there is a gap between the transformed deterministic constraints in case of known and unknown probability distribution. This paper examines the conservativeness of probabilistic constrained optimization method for unknown probability distribution. The objective of this paper is to provide a quantitative assessment of the conservatism for tractable constraints in probabilistic constrained optimization with unknown probability distribution.Keywords: Optimal control, stochastic systems, discrete-time systems, probabilistic constraints.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19112861 2-Dimensional Finger Gesture Based Mobile Robot Control Using Touch Screen
Authors: O. Ejale, N.B. Siddique, R. Seals
Abstract:
The purpose of this study was to present a reliable mean for human-computer interfacing based on finger gestures made in two dimensions, which could be interpreted and adequately used in controlling a remote robot's movement. The gestures were captured and interpreted using an algorithm based on trigonometric functions, in calculating the angular displacement from one point of touch to another as the user-s finger moved within a time interval; thereby allowing for pattern spotting of the captured gesture. In this paper the design and implementation of such a gesture based user interface was presented, utilizing the aforementioned algorithm. These techniques were then used to control a remote mobile robot's movement. A resistive touch screen was selected as the gesture sensor, then utilizing a programmed microcontroller to interpret them respectively.
Keywords: 2-Dimensional interface, finger gesture, mobile robot control, touch screen.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19152860 Radiobiological Model in Radiotherapy Planning for Prostate Cancer Treatment
Authors: Pradip Deb
Abstract:
Quantitative radiobiological models can be used to assess the optimum clinical outcome from sophisticated therapeutic modalities by calculating tumor control probability (TCP) and normal tissue complication probability (NTCP). In this study two 3D-CRT and an IMRT treatment plans were developed with an initial prescription dose of 60 Gy in 2 Gy/fraction to prostate. Sensitivity of TCP and Complication free tumor control probability (P+) to the different values of α/β ratio was investigated for various prescription doses planned to be delivered in either a fixed number of fractions (I) or in a fixed dose per fraction (II) in each of the three different treatment plans. High dose/fraction and high α/β value result in comparatively smaller P+ and IMRT plans resulted in the highest P+, mainly due to the decrease in NTCP. If α/β is lower than expected, better tumor control can be achieved by increasing dose/fraction but decreasing the number of fractions.Keywords: Linear Quadratic Model, TCP, NTCP, α/β ratio.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18422859 A Low Cost and High Quality Duty-Cycle Modulation Scheme and Applications
Authors: B. Lonla Moffo, J. Mbihi, L. Nneme Nneme
Abstract:
In this paper, a low cost duty-cycle modulation scheme is studied in depth and compared to the standard pulse width modulation technique. Using a mix of analytical reasoning and electronics simulation tools, it is shown that under the same operating conditions, most characteristics of the proposed duty-cycle modulation scheme are better than those provided by a standard pulse width modulation technique. The simulation results obtained when testing both modulation control policies on prototyping systems, indicate that the proposed duty-cycle modulation approach, appears to be a high quality control policy in a wide variety of application areas, including A/D and D/A conversion, signal transmission and switching control in power electronics.
Keywords: Duty-cycle Modulation, Operational amplifiers, Pulse width modulation, Power electronics, Signal processing.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27302858 Supervisor Controller-Based Colored Petri Nets for Deadlock Control and Machine Failures in Automated Manufacturing Systems
Authors: Husam Kaid, Abdulrahman Al-Ahmari, Zhiwu Li
Abstract:
This paper develops a robust deadlock control technique for shared and unreliable resources in automated manufacturing systems (AMSs) based on structural analysis and colored Petri nets, which consists of three steps. The first step involves using strict minimal siphon control to create a live (deadlock-free) system that does not consider resource failure. The second step uses an approach based on colored Petri net, in which all monitors designed in the first step are merged into a single monitor. The third step addresses the deadlock control problems caused by resource failures. For all resource failures in the Petri net model a common recovery subnet based on colored petri net is proposed. The common recovery subnet is added to the obtained system at the second step to make the system reliable. The proposed approach is evaluated using an AMS from the literature. The results show that the proposed approach can be applied to an unreliable complex Petri net model, has a simpler structure and less computational complexity, and can obtain one common recovery subnet to model all resource failures.
Keywords: Automated manufacturing system, colored Petri net, deadlock, siphon.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 4542857 Seismic Response Reduction of Structures using Smart Base Isolation System
Authors: H.S. Kim
Abstract:
In this study, control performance of a smart base isolation system consisting of a friction pendulum system (FPS) and a magnetorheological (MR) damper has been investigated. A fuzzy logic controller (FLC) is used to modulate the MR damper so as to minimize structural acceleration while maintaining acceptable base displacement levels. To this end, a multi-objective optimization scheme is used to optimize parameters of membership functions and find appropriate fuzzy rules. To demonstrate effectiveness of the proposed multi-objective genetic algorithm for FLC, a numerical study of a smart base isolation system is conducted using several historical earthquakes. It is shown that the proposed method can find optimal fuzzy rules and that the optimized FLC outperforms not only a passive control strategy but also a human-designed FLC and a conventional semi-active control algorithm.Keywords: Fuzzy logic controller, genetic algorithm, MR damper, smart base isolation system
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21822856 Global Chaos Synchronization of Identical and Nonidentical Chaotic Systems Using Only Two Nonlinear Controllers
Authors: Azizan Bin Saaban, Adyda Binti Ibrahim, Mohammad Shehzad, Israr Ahmad
Abstract:
In chaos synchronization, the main goal is to design such controller(s) that synchronizes the states of master and slave system asymptotically globally. This paper studied and investigated the synchronization problem of two identical Chen, and identical Tigan chaotic systems and two non-identical Chen and Tigan chaotic systems using Non-linear active control algorithm. In this study, based on Lyapunov stability theory and using non-linear active control algorithm, it has been shown that the proposed schemes have excellent transient performance using only two nonlinear controllers and have shown analytically as well as graphically that synchronization is asymptotically globally stable.
Keywords: Nonlinear Active Control, Chen and Tigan Chaotic systems, Lyapunov Stability theory, Synchronization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19472855 An Optimal Control Problem for Rigid Body Motions on Lie Group SO(2, 1)
Authors: Nemat Abazari, Ilgin Sager
Abstract:
In this paper smooth trajectories are computed in the Lie group SO(2, 1) as a motion planning problem by assigning a Frenet frame to the rigid body system to optimize the cost function of the elastic energy which is spent to track a timelike curve in Minkowski space. A method is proposed to solve a motion planning problem that minimize the integral of the square norm of Darboux vector of a timelike curve. This method uses the coordinate free Maximum Principle of Optimal control and results in the theory of integrable Hamiltonian systems. The presence of several conversed quantities inherent in these Hamiltonian systems aids in the explicit computation of the rigid body motions.
Keywords: Optimal control, Hamiltonian vector field, Darboux vector, maximum principle, lie group, Rigid body motion, Lorentz metric.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 13212854 A Quantitative Tool for Analyze Process Design
Authors: Andrés Carrión García, Aura López de Murillo, José Jabaloyes Vivas, Angela Grisales del Río
Abstract:
Some quality control tools use non metric subjective information coming from experts, who qualify the intensity of relations existing inside processes, but without quantifying them. In this paper we have developed a quality control analytic tool, measuring the impact or strength of the relationship between process operations and product characteristics. The tool includes two models: a qualitative model, allowing relationships description and analysis; and a formal quantitative model, by means of which relationship quantification is achieved. In the first one, concepts from the Graphs Theory were applied to identify those process elements which can be sources of variation, that is, those quality characteristics or operations that have some sort of prelacy over the others and that should become control items. Also the most dependent elements can be identified, that is those elements receiving the effects of elements identified as variation sources. If controls are focused in those dependent elements, efficiency of control is compromised by the fact that we are controlling effects, not causes. The second model applied adapts the multivariate statistical technique of Covariance Structural Analysis. This approach allowed us to quantify the relationships. The computer package LISREL was used to obtain statistics and to validate the model.
Keywords: Characteristics matrix, covariance structure analysis, LISREL.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15862853 Digital Automatic Gain Control Integrated on WLAN Platform
Authors: Emilija Miletic, Milos Krstic, Maxim Piz, Michael Methfessel
Abstract:
In this work we present a solution for DAGC (Digital Automatic Gain Control) in WLAN receivers compatible to IEEE 802.11a/g standard. Those standards define communication in 5/2.4 GHz band using Orthogonal Frequency Division Multiplexing OFDM modulation scheme. WLAN Transceiver that we have used enables gain control over Low Noise Amplifier (LNA) and a Variable Gain Amplifier (VGA). The control over those signals is performed in our digital baseband processor using dedicated hardware block DAGC. DAGC in this process is used to automatically control the VGA and LNA in order to achieve better signal-to-noise ratio, decrease FER (Frame Error Rate) and hold the average power of the baseband signal close to the desired set point. DAGC function in baseband processor is done in few steps: measuring power levels of baseband samples of an RF signal,accumulating the differences between the measured power level and actual gain setting, adjusting a gain factor of the accumulation, and applying the adjusted gain factor the baseband values. Based on the measurement results of RSSI signal dependence to input power we have concluded that this digital AGC can be implemented applying the simple linearization of the RSSI. This solution is very simple but also effective and reduces complexity and power consumption of the DAGC. This DAGC is implemented and tested both in FPGA and in ASIC as a part of our WLAN baseband processor. Finally, we have integrated this circuit in a compact WLAN PCMCIA board based on MAC and baseband ASIC chips designed from us.Keywords: WLAN, AGC, RSSI, baseband processor
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 3934