Search results for: parenting psychological control
11689 Determination of Critical Period for Weed Control in the Second Crop Forage Maize (454 Cultivar)
Authors: Farhad Farahvash, Parya Mobaseri
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Weeds control based on their critical period leads to less production costs and risks of wide chemical application of weeds control methods. The present study considered effect of weeds control time (weeds interference after 20, 40 and 60 days, weeds full control, weeds interference and weeds control after 20, 40 and 60 days) on growth and yield of forage maize 454. The experiment based on full-randomized blocks design with three replications was conducted at research farm of Islamic Azad University of Tabriz located at 15th km of East Tabriz in 2013. According to the results, weeds interference after 40 and 60 days as well as weeds control after 20 days prevented from decrease of maize biomass resulted from weeds presence while weeds interference after 20 days, weeds interference and weeds control after 40 and 60 days led respectively to 41.2%, 35%, 25% and 32.5% decrease of forage maize biomass. The weeds-influenced decrease was manifested at different parts of the plant depending on presence period of weeds. Decrease of fresh weight of ear and fresh weight of leaf and stem was observed due to weeds interference after 20 days and weeds interference. If weeds are controlled after 60 days, decrease of ear weight and fresh weight of stem will lead to biomass decrease. Also, if weeds are controlled after 40 days, decrease of fresh weight of maize stems will result in biomass decrease. Ear traits were affected by weeds control treatment. Being affected by treatments of weeds interference after 20 days, weeds non-interference, weeds control after 40 and 60 days, ear length was shortened 29.9 %, 41.4 %, 27.6 % and 37.2 %, respectively. The stem diameter demonstrated a significant decrease although it was only affected by treatments of weeds interference and weeds control after 60 days. Considering results of the present study, generally, it is suggested to control weeds during initial 20-60 days of maize growth in order to prevent undesirable effect of weeds on growth, production and production biomass of maize and decrease of production costs.Keywords: maize, competition, weed, biomass
Procedia PDF Downloads 35611688 Efficient Control of Brushless DC Motors with Pulse Width Modulation
Authors: S. Shahzadi, J. Rizk
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This paper describes the pulse width modulated control of a three phase, 4 polar DC brushless motor. To implement this practically the Atmel’s AVR ATmega 328 microcontroller embedded on an Arduino Eleven board is utilized. The microcontroller programming is done in an open source Arduino IDE development environment. The programming logic effectively manipulated a six MOSFET bridge which was used to energize the stator windings as per control requirements. The results obtained showed accurate, precise and efficient pulse width modulated operation. Another advantage offered by this pulse width modulated control was the efficient speed control of the motor. By varying the time intervals between successive commutations, faster energizing of the stator windings was possible thereby leading to quicker rotor alignment with these energized phases and faster revolutions.Keywords: brushless DC motors, commutation, MOSFET, PWM
Procedia PDF Downloads 50311687 Hairy Beggarticks (Bidens pilosa L. - Asteraceae) Control in Sunflower Fields Using Pre-Emergence Herbicides
Authors: Alexandre M. Brighenti
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One of the most damaging species in sunflower crops in Brazil is the hairy beggarticks (Bidens pilosa L.). The large number of seeds, the various vegetative cycles during the year, the staggered germination and the scarcity of selective and effective herbicides to control this weed in sunflower are some of attributes that hinder the effectiveness in controlling hairy beggarticks populations. The experiment was carried out with the objectives of evaluating the control of hairy beggarticks plants in sunflower crops, and to assess sunflower tolerance to residual herbicides. The treatments were as follows: S-metolachlor (1,200 and 2,400 g ai ha-1), flumioxazin (60 and 120 g ai ha-1), sulfentrazone (150 and 300 g ai ha-1) and two controls (weedy and weed-free check). Phytotoxicity on sunflower plants, percentage of control and density of hairy beggarticks plants, sunflower stand and plant height, head diameter, oil content and sunflower yield were evaluated. The herbicides flumioxazin and sulfentrazone were the most efficient in hairy beggarticks control. S-metolachlor provided acceptable control levels. S-metolachlor (1,200 g ha-1), flumioxazin (60 g ha-1) and sulfentrazone (150 g ha-1) were the most selective doses for sunflower crop.Keywords: flumioxazin, Helianthus annuus, S-metolachlor, sulfentrazone, weeds
Procedia PDF Downloads 35011686 Assessing Measures and Caregiving Experiences of Thai Caregivers of Persons with Dementia
Authors: Piyaorn Wajanatinapart, Diane R. Lauver
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The number of persons with dementia (PWD) has increased. Informal caregivers are the major providing care. They can have perceived gains and burdens. Caregivers who reported high in perceived gains may report low in burdens and better health. Gaps of caregiving literature were: no report psychometrics in a few studies and unclear definitions of gains; most studies with no theory-guided and conducting in Western countries; not fully described relationships among caregiving variables: motivations, satisfaction with psychological needs, social support, gains, burdens, and physical and psycho-emotional health. Those gaps were filled by assessing psychometric properties of selected measures, providing clearly definitions of gains, using self-determination theory (SDT) to guide the study, and developing the study in Thailand. The study purposes were to evaluate six measures for internal consistency reliability, content validity, and construct validity. This study also examined relationships of caregiving variables: motivations (controlled and autonomous motivations), satisfaction with psychological needs (autonomy, competency, and relatedness), perceived social support, perceived gains, perceived burdens, and physical and psycho-emotional health. This study was a cross-sectional and correlational descriptive design with two convenience samples. Sample 1 was five Thai experts to assess content validity of measures. Sample 2 was 146 Thai caregivers of PWD to assess construct validity, reliability, and relationships among caregiving variables. Experts rated questionnaires and sent them back via e-mail. Caregivers answered questionnaires at clinics of four Thai hospitals. Data analysis was used descriptive statistics and bivariate and multivariate analyses using the composite indicator structural equation model to control measurement errors. For study results, most caregivers were female (82%), middle age (M =51.1, SD =11.9), and daughters (57%). They provided care for 15 hours/day with 4.6 years. The content validity indices of items and scales were .80 or higher for clarity and relevance. Experts suggested item revisions. Cronbach’s alphas were .63 to .93 of ten subscales of four measures and .26 to .57 of three subscales. The gain scale was acceptable for construct validity. With controlling covariates, controlled motivations, the satisfaction with three subscales of psychological needs, and perceived social support had positive relationships with physical and psycho-emotional health. Both satisfaction with autonomy subscale and perceived social support had negative relationship with perceived burdens. The satisfaction with three subscales of psychological needs had positive relationships among them. Physical and psycho-emotional health subscales had positive relationships with each other. Furthermore, perceived burdens had negative relationships with physical and psycho-emotional health. This study was the first use SDT to describe relationships of caregiving variables in Thailand. Caregivers’ characteristics were consistent with literature. Four measures were valid and reliable except two measures. Breadth knowledge about relationships was provided. Interpretation of study results was cautious because of using same sample to evaluate psychometric properties of measures and relationships of caregiving variables. Researchers could use four measures for further caregiving studies. Using a theory would help describe concepts, propositions, and measures used. Researchers may examine the satisfaction with psychological needs as mediators. Future studies to collect data with caregivers in communities are needed.Keywords: caregivers, caregiving, dementia, measures
Procedia PDF Downloads 29911685 SPBAC: A Semantic Policy-Based Access Control for Database Query
Authors: Aaron Zhang, Alimire Kahaer, Gerald Weber, Nalin Arachchilage
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Access control is an essential safeguard for the security of enterprise data, which controls users’ access to information resources and ensures the confidentiality and integrity of information resources [1]. Research shows that the more common types of access control now have shortcomings [2]. In this direction, to improve the existing access control, we have studied the current technologies in the field of data security, deeply investigated the previous data access control policies and their problems, identified the existing deficiencies, and proposed a new extension structure of SPBAC. SPBAC extension proposed in this paper aims to combine Policy-Based Access Control (PBAC) with semantics to provide logically connected, real-time data access functionality by establishing associations between enterprise data through semantics. Our design combines policies with linked data through semantics to create a "Semantic link" so that access control is no longer per-database and determines that users in each role should be granted access based on the instance policy, and improves the SPBAC implementation by constructing policies and defined attributes through the XACML specification, which is designed to extend on the original XACML model. While providing relevant design solutions, this paper hopes to continue to study the feasibility and subsequent implementation of related work at a later stage.Keywords: access control, semantic policy-based access control, semantic link, access control model, instance policy, XACML
Procedia PDF Downloads 8011684 Comparing the Effectiveness of Social Skills Training and Stress Management on Self Esteem and Agression in First Grade Students of Iranian West High School
Authors: Hossein Nikandam Kermanshah, Babak Samavatian, Akbar Hemmati Sabet, Mohammad Ahmadpanah
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This is a quasi-experimental study that has been conducted in order to compare the effectiveness of social skills training and stress management training on self-esteem and aggression in first grade high school students. Forty-five people were selected from research community and were put randomly in there groups of social skills training, stress management training and control ones. Collecting data tools in this study was devise, self-esteem and AGQ aggression questionnaire. Self-esteem and aggression questionnaires has been conducted as the pre-test and post-test. Social skills training and stress management groups participated in eight 1.5 hour session in a week. But control group did not receive any therapy. For descriptive analysis of data, statistical indicators like mean, standard deviation were used, and in inferential statistics level multi variable covariance analysis have been used. The finding result show that group training social skills and stress management is significantly effective on the self-esteem and aggression, there is a meaningful difference between training social skills and stress management on self-esteem that the preference is with group social skills training, in the difference between group social skills training and stress management on aggression, the preference is with group stress management.Keywords: social skill training, stress management training, self-esteem aggression, psychological sciences
Procedia PDF Downloads 46211683 Autonomous Control of Ultrasonic Transducer Drive System
Authors: Dong-Keun Jeong, Jong-Hyun Kim, Woon-Ha Yoon, Hee-Je Kim
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In order to automatically operate the ultrasonic transducer drive system for sonicating aluminum, this paper proposes the ultrasonic transducer sensorless control algorithm. The resonance frequency shift and electrical impedance change is a common phenomenon in the state of the ultrasonic transducer. The proposed control algorithm make use of the impedance change of ultrasonic transducer according to the environment between air state and aluminum alloy state, it controls the ultrasonic transducer drive system autonomous without a sensor. The proposed sensorless autonomous ultrasonic transducer control algorithm was experimentally verified using a 3kW prototype ultrasonic transducer drive system.Keywords: ultrasonic transducer drive system, impedance change, sensorless, autonomous control algorithm
Procedia PDF Downloads 35311682 Design and Implementation of Control System in Underwater Glider of Ganeshblue
Authors: Imam Taufiqurrahman, Anugrah Adiwilaga, Egi Hidayat, Bambang Riyanto Trilaksono
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Autonomous Underwater Vehicle glider is one of the renewal of underwater vehicles. This vehicle is one of the autonomous underwater vehicles that are being developed in Indonesia. Glide ability is obtained by controlling the buoyancy and attitude of the vehicle using the movers within the vehicle. The glider motion mechanism is expected to provide energy resistance from autonomous underwater vehicles so as to increase the cruising range of rides while performing missions. The control system on the vehicle consists of three parts: controlling the attitude of the pitch, the buoyancy engine controller and the yaw controller. The buoyancy and pitch controls on the vehicle are sequentially referring to the finite state machine with pitch angle and depth of diving inputs to obtain a gliding cycle. While the yaw control is done through the rudder for the needs of the guide system. This research is focused on design and implementation of control system of Autonomous Underwater Vehicle glider based on PID anti-windup. The control system is implemented on an ARM TS-7250-V2 device along with a mathematical model of the vehicle in MATLAB using the hardware-in-the-loop simulation (HILS) method. The TS-7250-V2 is chosen because it complies industry standards, has high computing capability, minimal power consumption. The results show that the control system in HILS process can form glide cycle with depth and angle of operation as desired. In the implementation using half control and full control mode, from the experiment can be concluded in full control mode more precision when tracking the reference. While half control mode is considered more efficient in carrying out the mission.Keywords: control system, PID, underwater glider, marine robotics
Procedia PDF Downloads 36411681 Investigation of the GFR2400 Reactivity Control System
Authors: Ján Haščík, Štefan Čerba, Jakub Lüley, Branislav Vrban
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The presented paper is related to the design methods and neutronic characterization of the reactivity control system in the large power unit of Generation IV Gas cooled Fast Reactor – GFR2400. The reactor core is based on carbide pin fuel type with the application of refractory metallic liners used to enhance the fission product retention of the SiC cladding. The heterogeneous design optimization of control rod is presented and the results of rods worth and their interferences in a core are evaluated. In addition, the idea of reflector removal as an additive reactivity management option is investigated and briefly described.Keywords: control rods design, GFR2400, hot spot, movable reflector, reactivity
Procedia PDF Downloads 43411680 Sliding Mode Control of Variable Speed Wind Energy Conversion Systems
Authors: Zine Souhila Rached, Mazari Benyounes Bouzid, Mohamed Amine, Allaoui Tayeb
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Wind energy has many advantages, it does not pollute and it is an inexhaustible source. However, its high cost is a major constraint, especially on the less windy sites. The purpose of wind energy systems is to maximize energy efficiency, and extract maximum power from the wind speed. In other words, having a power coefficient is maximum and therefore the maximum power point tracking. In this case, the MPPT control becomes important.To realize this control, strategy conventional proportional and integral (PI) controller is usually used. However, this strategy cannot achieve better performance. This paper proposes a robust control of a turbine which optimizes its production, that is improve the quality and energy efficiency, namely, a strategy of sliding mode control. The proposed sliding mode control strategy presents attractive features such as robustness to parametric uncertainties of the turbine; the proposed sliding mode control approach has been simulated on three-blade wind turbine. The simulation result under Matlab\Simulink has validated the performance of the proposed MPPT strategy.Keywords: wind turbine, maximum power point tracking, sliding mode, energy conversion systems
Procedia PDF Downloads 60411679 Application of Hyperbinomial Distribution in Developing a Modified p-Chart
Authors: Shourav Ahmed, M. Gulam Kibria, Kais Zaman
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Control charts graphically verify variation in quality parameters. Attribute type control charts deal with quality parameters that can only hold two states, e.g., good or bad, yes or no, etc. At present, p-control chart is most commonly used to deal with attribute type data. In construction of p-control chart using binomial distribution, the value of proportion non-conforming must be known or estimated from limited sample information. As the probability distribution of fraction non-conforming (p) is considered in hyperbinomial distribution unlike a constant value in case of binomial distribution, it reduces the risk of false detection. In this study, a statistical control chart is proposed based on hyperbinomial distribution when prior estimate of proportion non-conforming is unavailable and is estimated from limited sample information. We developed the control limits of the proposed modified p-chart using the mean and variance of hyperbinomial distribution. The proposed modified p-chart can also utilize additional sample information when they are available. The study also validates the use of modified p-chart by comparing with the result obtained using cumulative distribution function of hyperbinomial distribution. The study clearly indicates that the use of hyperbinomial distribution in construction of p-control chart yields much accurate estimate of quality parameters than using binomial distribution.Keywords: binomial distribution, control charts, cumulative distribution function, hyper binomial distribution
Procedia PDF Downloads 27311678 Study on Planning of Smart GRID Using Landscape Ecology
Authors: Sunglim Lee, Susumu Fujii, Koji Okamura
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Smart grid is a new approach for electric power grid that uses information and communications technology to control the electric power grid. Smart grid provides real-time control of the electric power grid, controlling the direction of power flow or time of the flow. Control devices are installed on the power lines of the electric power grid to implement smart grid. The number of the control devices should be determined, in relation with the area one control device covers and the cost associated with the control devices. One approach to determine the number of the control devices is to use the data on the surplus power generated by home solar generators. In current implementations, the surplus power is sent all the way to the power plant, which may cause power loss. To reduce the power loss, the surplus power may be sent to a control device and sent to where the power is needed from the control device. Under assumption that the control devices are installed on a lattice of equal size squares, our goal is to figure out the optimal spacing between the control devices, where the power sharing area (the area covered by one control device) is kept small to avoid power loss, and at the same time the power sharing area is big enough to have no surplus power wasted. To achieve this goal, a simulation using landscape ecology method is conducted on a sample area. First an aerial photograph of the land of interest is turned into a mosaic map where each area is colored according to the ratio of the amount of power production to the amount of power consumption in the area. The amount of power consumption is estimated according to the characteristics of the buildings in the area. The power production is calculated by the sum of the area of the roofs shown in the aerial photograph and assuming that solar panels are installed on all the roofs. The mosaic map is colored in three colors, each color representing producer, consumer, and neither. We started with a mosaic map with 100 m grid size, and the grid size is grown until there is no red grid. One control device is installed on each grid, so that the grid is the area which the control device covers. As the result of this simulation we got 350 m as the optimal spacing between the control devices that makes effective use of the surplus power for the sample area.Keywords: landscape ecology, IT, smart grid, aerial photograph, simulation
Procedia PDF Downloads 43711677 A Two Year Follow Up of Sexually Abused Children
Authors: Horesh Reinman Netta
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Early research on child sexual abuse (CSA) attempted to assess its possible effects. Researchers found that victims of CSA are prone to a host of emotional disorders, including post-traumatic stress disorder, depression, dissociative disorders, anxiety disorders and suicidality later in life. The study examined the development of symptoms over a two-year period at base line and after six months. Factors including the age at the onset of abuse, the gender of the abused child and academic achievements were also examined. Other variables examined include the complex association among self-disclosure, self-esteem, the child’s attachment and coping styles, and psychological adjustment. The abused child’s domestic environment has been found to have a relevant impact on the psychological outcomes of CSA. The study examined inter-parental conflicts, cohesion in the child’s home, parental attachment styles and psychopathology. To the best of our knowledge, no investigation of this nature has yet been performed. Hence, the study makes a major contribution to research in this field. In addition, a combined examination of abuse characteristics, child characteristics, domestic environment and therapeutic history will facilitate enhanced understanding of the interactions among CSA, mediating factors and psychological outcomes.Keywords: sexual abuse, follow up, victimization, children
Procedia PDF Downloads 7011676 A Study of the Disorders of Sexual Functioning in Women with Type 2 Diabetes Mellitus in a Tertiary Care Hospital in India
Authors: Mehak Nagpal, T. S. Sathyanarayan Rao
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Background: Sexual functioning is a neglected aspect of health in women with diabetes, though it contributes greatly towards quality of life and feeling of wellbeing. Also women with DM are at higher risk than men of developing sexual dysfunction and depression. Materials and Methods: Cross-sectional comparison study. Sample size: 100 previously diagnosed type 2DM patients attending Outpatient Diabetic Clinic at Medicine department JSS Hospital Mysore; aged 20-65 years and 60 normal healthy female subjects for Control group. Data was collected with ethical approval over a period of 2 years. Tools Used: 1) Hamilton Depression Rating Scale (HAMD – 17 item) 2) Female Sexual Functioning Index (FSFI) 3) Arizona Sexual Experience Scale (ASEX-F) for female-for screening. 4) The Appraisal of Diabetes Scale (ADS). Results: Statistically significant differences were observed in prevalence rate and severity of depression between diabetic group (45% vs 11% syndromal depression) and controls. Depression scores correlated significantly with glycaemic control, adherence to treatment, BMI and the cognitive appraisal of diabetes. There was significantly greater impairment in the sexual functioning of women with type 2 diabetes mellitus as compared to controls; both prevalence (62% vs 38.3%) and severity (p value < 0.01). Arousal (74.2% vs 53.3%), Desire (76.3% vs 50%) and Satisfaction (76.7% vs 63.7%) were most affected and 64.5% were affected in 2 or more domains. A negative illness appraisal on ADS correlated significantly with poor glycaemic control, higher rates of depression and also more severe female sexual dysfunction (p value < 0.05). Conclusion: Diabetes specific factors that correlated significantly with FSD in this study included the psychological appraisal of diabetes, duration of diabetes, presence of complications and BMI.Keywords: depression, female sexual dysfunction, India, type 2 diabetes mellitus
Procedia PDF Downloads 32511675 REFLEX: A Randomized Controlled Trial to Test the Efficacy of an Emotion Regulation Flexibility Program with Daily Measures
Authors: Carla Nardelli, Jérome Holtzmann, Céline Baeyens, Catherine Bortolon
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Background. Emotion regulation (ER) is a process associated with difficulties in mental health. Given its transdiagnostic features, its improvement could facilitate the recovery of various psychological issues. A limit of current studies is the lack of knowledge regarding whether available interventionsimprove ER flexibility (i.e., the ability to implement ER strategies in line with contextual demands), even though this capacity has been associated with better mental health and well-being. Therefore, the aim of the study is to test the efficacy of a 9-weeks ER group program (the Affect Regulation Training-ART), using the most appropriate measures (i.e., experience sampling method) in a student population. Plus, the goal of the study is to explore the potential mediative role of ER flexibility on mental health improvement. Method. This Randomized Controlled Trial will comparethe ER program group to an active control group (a relaxation program) in 100 participants. To test the mediative role of ER flexibility on mental health, daily measures will be used before, during, and after the interventions to evaluate the extent to which participants are flexible in their ER. Expected outcomes. Using multilevel analyses, we expect an improvement in anxious-depressive symptomatology for both groups. However, we expect the ART group to improve specifically on ER flexibility ability and the last to be a mediative variable on mental health. Conclusion. This study will enhance knowledge on interventions for students and the impact of interventions on ER flexibility. Also, this research will improve knowledge on ecological measures for assessing the effect of interventions. Overall, this project represents new opportunities to improve ER skills to improve mental health in undergraduate students.Keywords: emotion regulation flexibility, experience sampling method, psychological intervention, emotion regulation skills
Procedia PDF Downloads 12911674 Chaotic Control, Masking and Secure Communication Approach of Supply Chain Attractor
Authors: Unal Atakan Kahraman, Yilmaz Uyaroğlu
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The chaotic signals generated by chaotic systems have some properties such as randomness, complexity and sensitive dependence on initial conditions, which make them particularly suitable for secure communications. Since the 1990s, the problem of secure communication, based on chaos synchronization, has been thoroughly investigated and many methods, for instance, robust and adaptive control approaches, have been proposed to realize the chaos synchronization. In this paper, an improved secure communication model is proposed based on control of supply chain management system. Control and masking communication simulation results are used to visualize the effectiveness of chaotic supply chain system also performed on the application of secure communication to the chaotic system. So, we discover the secure phenomenon of chaos-amplification in supply chain systemKeywords: chaotic analyze, control, secure communication, supply chain attractor
Procedia PDF Downloads 50611673 Modelling and Technical Assessment of Multi-Motor for Electric Vehicle Drivetrains by Using Electric Differential
Authors: Mohamed Abdel-Monem, Gamal Sowilam, Omar Hegazy
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This paper presents a technical assessment of an electric vehicle with two independent rear-wheel motor and an improved traction control system. The electric differential and the control strategy have been implemented to assure that in a straight trajectory, the two rear-wheels run exactly at the same speed, considering the same/different road conditions under the left and right side of the wheels. In case of turning to right/left, the difference between the two rear-wheels speeds assures a vehicle trajectory without sliding, thanks to a harmony between the electric differential and the control strategy. The present article demonstrates a complete model and analysis of a traction control system, considering four different traction scenarios, for two independent rear-wheels motors for electric vehicles. Furthermore, the vehicle model, including wheel dynamics, load forces, electric differential, and control strategy, is designed and verified by using MATLAB/Simulink environment.Keywords: electric vehicle, energy saving, multi-motor, electric differential, simulation and control
Procedia PDF Downloads 34811672 PEA Design of the Direct Control for Training Motor Drives
Authors: Abdulatif Abdulsalam Mohamed Shaban
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This paper states that the art of Procedure Entry Array (PEA) plan with a focus on control system applications. This paper begins with an impression of PEA technology development, followed by an arrangement of design technologies, and the use of programmable description languages and system-level design tools. They allow a practical approach based on a unique model for complete engineering electronics systems. There are three main design rules are implemented in the system. These are algorithm based fine-tuning, modularity, and the control act and the architectural constraints. An overview of contributions and limits of PEAs is also given, followed by a short survey of PEA-based gifted controllers for recent engineering systems. Finally, two complete and timely case studies are presented to illustrate the benefits of a PEA implementation when using the proposed system modelling and devise attitude. These consist of the direct control for training motor drives and the control of a diesel-driven stand-alone generator with the help of logical design.Keywords: control (DC), engineering electronics systems, training motor drives, procedure entry array
Procedia PDF Downloads 50911671 Optimization Design of Single Phase Inverter Connected to the Grid
Authors: Linda Hassaine, Abdelhamid Mraoui, Mohamed Rida Bengourina
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In grid-connected photovoltaic systems, significant improvements can be carried out in the design and implementation of inverters: reduction of harmonic distortion, elimination of the DC component injected into the grid and the proposed control. This paper proposes a control strategy based on PWM switching patterns for an inverter for the photovoltaic system connected to the grid in order to control the injected current. The current injected must be sinusoidal with reduced harmonic distortion. An additional filter is designed to reduce high-order harmonics on the output side. This strategy exhibits the advantages: Simplicity, reduction of harmonics, the size of the line filter, reduction of the memory requirements and power calculation for the control.Keywords: control, inverters, LCL filter, grid-connected photovoltaic system
Procedia PDF Downloads 31811670 Iterative Design Process for Development and Virtual Commissioning of Plant Control Software
Authors: Thorsten Prante, Robert Schöch, Ruth Fleisch, Vaheh Khachatouri, Alexander Walch
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The development of industrial plant control software is a complex and often very expensive task. One of the core problems is that a lot of the implementation and adaptation work can only be done after the plant hardware has been installed. In this paper, we present our approach to virtually developing and validating plant-level control software of production plants. This way, plant control software can be virtually commissioned before actual ramp-up of a plant, reducing actual commissioning costs and time. Technically, this is achieved by linking the actual plant-wide process control software (often called plant server) and an elaborate virtual plant model together to form an emulation system. Method-wise, we are suggesting a four-step iterative process with well-defined increments and time frame. Our work is based on practical experiences from planning to commissioning and start-up of several cut-to-size plants.Keywords: iterative system design, virtual plant engineering, plant control software, simulation and emulation, virtual commissioning
Procedia PDF Downloads 47911669 The Causes of Non-Disclosure of Intrafamilial Childhood Sexual Abuse and Its Effects
Authors: Ishtiaque Qureshi, Erum Muzaffar
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This study aimed to analyze the causes of non-disclosure of intrafamilial childhood sexual abuse (IFCSA) among survivors studying in higher education institutions in Sindh, Pakistan. Employing a mixed-method approach, the research investigated the reasons behind non-disclosure. A quantitative survey conducted in higher education institutions identified IFCSA victims through purposive sampling, and the causes were assessed through in-depth interviews with 18 respondents. Subsequent analysis of the interview transcripts resulted in the categorization of respondents into three groups: (1) those fearing the consequences of revealing facts to their parents, (2) individuals unwilling to subject their parents to conflict with the perpetrator, and (3) those who could not disclose the abuse due to reasons not understood by them. Correlations among non-disclosing respondents were examined with respect to their socio-economic status, family structure, emotional availability of parents, and parenting style.Keywords: intrafamilial childhood sexual abuse, non-disclosure, survivors of IFCSA, in-depth interviews
Procedia PDF Downloads 4711668 Jointly Optimal Statistical Process Control and Maintenance Policy for Deteriorating Processes
Authors: Lucas Paganin, Viliam Makis
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With the advent of globalization, the market competition has become a major issue for most companies. One of the main strategies to overcome this situation is the quality improvement of the product at a lower cost to meet customers’ expectations. In order to achieve the desired quality of products, it is important to control the process to meet the specifications, and to implement the optimal maintenance policy for the machines and the production lines. Thus, the overall objective is to reduce process variation and the production and maintenance costs. In this paper, an integrated model involving Statistical Process Control (SPC) and maintenance is developed to achieve this goal. Therefore, the main focus of this paper is to develop the jointly optimal maintenance and statistical process control policy minimizing the total long run expected average cost per unit time. In our model, the production process can go out of control due to either the deterioration of equipment or other assignable causes. The equipment is also subject to failures in any of the operating states due to deterioration and aging. Hence, the process mean is controlled by an Xbar control chart using equidistant sampling epochs. We assume that the machine inspection epochs are the times when the control chart signals an out-of-control condition, considering both true and false alarms. At these times, the production process will be stopped, and an investigation will be conducted not only to determine whether it is a true or false alarm, but also to identify the causes of the true alarm, whether it was caused by the change in the machine setting, by other assignable causes, or by both. If the system is out of control, the proper actions will be taken to bring it back to the in-control state. At these epochs, a maintenance action can be taken, which can be no action, or preventive replacement of the unit. When the equipment is in the failure state, a corrective maintenance action is performed, which can be minimal repair or replacement of the machine and the process is brought to the in-control state. SMDP framework is used to formulate and solve the joint control problem. Numerical example is developed to demonstrate the effectiveness of the control policy.Keywords: maintenance, semi-Markov decision process, statistical process control, Xbar control chart
Procedia PDF Downloads 8511667 Significance of Occupational Safety for Healthcare Professionals
Authors: Nilgün Katrancı, Pınar Göv
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The privatization of public services has intensified and extended the delivery of healthcare services at hospitals, which leads to an increase in health and safety risks for healthcare professionals. More efficient and effective delivery of healthcare services can be realized through the provision of occupational safety of healthcare professionals. However, healthcare professionals are exposed to more dangers, accidents, and diseases because of such reasons as present working conditions, hospital infections, lack of ergonomic design, medication, wastes, excessive work load, negligent attitudes of workers, violence, psychological risks, etc. Unsafe working conditions cause fear, injury and wearing impacts in healthcare professionals in many countries. Thus, it is emphasized that the protection of the health of healthcare professionals is important to have educated, healthy workers and adequate workforce. Occupational health and safety measures applied in health facilities are aimed at protecting workers and providing the safety of services and facilities. All activities to be undertaken at hospitals with regard to occupational safety in accordance with these goals will help to reduce costs and provide continuous services. At the same time, a safe working environment will increase worker satisfaction and motivation, sense of institutional belonging and indirectly patient safety and satisfaction. In addition, the control and correction of occupational safety activities are also as important as the implementation. Occupational health and safety practices in the facilities will also lead to positive developments for national economy and society. This study emphasizes that approaching occupational safety practices for healthcare professionals in a sensitive manner is important for enabling healthcare professionals to do more productive works in terms of physical, social and psychological aspects, maintaining the continuity of healthcare services and social and economic contributions.Keywords: health facilities, healthcare professional, occupational health, occupational safety
Procedia PDF Downloads 37811666 Integrated Braking and Traction Torque Vectoring Control Based on Vehicle Yaw Rate for Stability improvement of All-Wheel-Drive Electric Vehicles
Authors: Mahmoud Said Jneid, Péter Harth
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EVs with independent wheel driving greatly improve vehicle stability in poor road conditions. Wheel torques can be precisely controlled through electric motors driven using advanced technologies. As a result, various types of advanced chassis assistance systems (ACAS) can be implemented. This paper proposes an integrated torque vectoring control based on wheel slip regulation in both braking and traction modes. For generating the corrective yaw moment, the vehicle yaw rate and sideslip angle are monitored. The corrective yaw moment is distributed into traction and braking torques based on an equal-opposite components approach. The proposed torque vectoring control scheme is validated in simulation and the results show its superiority when compared to conventional schemes.Keywords: all-wheel-drive, electric vehicle, torque vectoring, regenerative braking, stability control, traction control, yaw rate control
Procedia PDF Downloads 8111665 H∞ Sampled-Data Control for Linear Systems Time-Varying Delays: Application to Power System
Authors: Chang-Ho Lee, Seung-Hoon Lee, Myeong-Jin Park, Oh-Min Kwon
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This paper investigates improved stability criteria for sampled-data control of linear systems with disturbances and time-varying delays. Based on Lyapunov-Krasovskii stability theory, delay-dependent conditions sufficient to ensure H∞ stability for the system are derived in the form of linear matrix inequalities(LMI). The effectiveness of the proposed method will be shown in numerical examples.Keywords: sampled-data control system, Lyapunov-Krasovskii functional, time delay-dependent, LMI, H∞ control
Procedia PDF Downloads 31711664 T-S Fuzzy Modeling Based on Power Coefficient Limit Nonlinearity Applied to an Isolated Single Machine Load Frequency Deviation Control
Authors: R. S. Sheu, H. Usman, M. S. Lawal
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Takagi-Sugeno (T-S) fuzzy model based control of a load frequency deviation in a single machine with limit nonlinearity on power coefficient is presented in the paper. Two T-S fuzzy rules with only rotor angle variable as input in the premise part, and linear state space models in the consequent part involving characteristic matrices determined from limits set on the power coefficient constant are formulated, state feedback control gains for closed loop control was determined from the formulated Linear Matrix Inequality (LMI) with eigenvalue optimization scheme for asymptotic and exponential stability (speed of esponse). Numerical evaluation of the closed loop object was carried out in Matlab. Simulation results generated of both the open and closed loop system showed the effectiveness of the control scheme in maintaining load frequency stability.Keywords: T-S fuzzy model, state feedback control, linear matrix inequality (LMI), frequency deviation control
Procedia PDF Downloads 39011663 The Desire to Know: Arnold’s Contribution to a Psychological Conceptualization of Academic Motivation
Authors: F. Ruiz-Fuster
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Arnold’s redefinition of human motives can sustain a psychology of education which emphasizes the beauty of knowledge and the exercise of intellectual functions. Thus, education instead of focusing on skills and learning by doing would be centered on ‘the widest reaches of the human spirit’. One way to attain it is by developing children’s inherent interest. Arnold takes into account the fact that the desire to know is the inherent interest which leads students to explore and learn. She also emphasizes the need of exercising human functions as thinking, judging and reasoning. According to Arnold, the influence of psychological theories of motivation in education has derived in considering that all learning and school tasks should derive from children’s needs and impulses. The desire to know and the curiosity have not been considered as basic and active as any instinctive drive or basic need, so there has been an attempt to justify and understand how biological drives guide student’s learning. However, understanding motives and motivation not as a drive, an instinct or an impulse guided by our basic needs, but as a want that leads to action can help to understand, from a psychological perspective, how teachers can motivate students to learn, strengthening their desire and interest to reason and discover the whole new world of knowledge.Keywords: academic motivation, interests, desire to know, educational psychology, intellectual functions
Procedia PDF Downloads 14711662 Economic Recession and its Psychological Effects on Educated Youth: A Case Study of Pakistan
Authors: Aroona Hashmi
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An economic recession can lead people to feel more insecure about their financial situation. The series of events leading into a recession can be especially distressing for Educated Youth. One of the most salient factors linking economic recession to psychological distress is unemployment. It is proved that a large number of educated young people are facing higher unemployment rate in Pakistan. Young people are likely to get frustrated at the lack of opportunities made available to them. If the young population increases more rapidly than job opportunities, then number of unemployment is likely to increase. The aim of present study was to investigate the relationship between economic instability, growing rate of aggression and frustration among educated youth. The study aimed to find out the impact of increased economic instability on the learning abilities of the students. Data was gathered from six university students of Punjab, Pakistan. The sample of the study consisted of three hundred male and female university students. The data was analyzed by applying Chi -square test. The results of the research indicate that there is a significant relationship between low household income and growing rate of aggression among educated youth. The increasing trend of economic instability significantly influences the learning abilities of the students. The study concludes that feeling of deprivation produce frustration and could be expressed through aggression. Therefore, if factors that are responsible for youth unemployment in Pakistan are addressed, psychological effects will be reduced. The right way of tackling the youth bulge is to turn the youth into a productive workforce. There is a dire need to transform the education system to societal needs. At the same time creating demand for the young workforce is achieved through dynamic changes in the economic structure.Keywords: psychological effects, economic recession, educated youth, environmental factors
Procedia PDF Downloads 38311661 PWM Based Control of Dstatcom for Voltage Sag, Swell Mitigation in Distribution Systems
Authors: A. Assif
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This paper presents the modeling of a prototype distribution static compensator (D-STATCOM) for voltage sag and swell mitigation in an unbalanced distribution system. Here the concept that an inverter can be used as generalized impedance converter to realize either inductive or capacitive reactance has been used to mitigate power quality issues of distribution networks. The D-STATCOM is here supposed to replace the widely used StaticVar Compensator (SVC). The scheme is based on the Voltage Source Converter (VSC) principle. In this model PWM based control scheme has been implemented to control the electronic valves of VSC. Phase shift control Algorithm method is used for converter control. The D-STATCOM injects a current into the system to mitigate the voltage sags. In this paper the modeling of D¬STATCOM has been designed using MATLAB SIMULINIC. Accordingly, simulations are first carried out to illustrate the use of D-STATCOM in mitigating voltage sag in a distribution system. Simulation results prove that the D-STATCOM is capable of mitigating voltage sag as well as improving power quality of a system.Keywords: D-STATCOM, voltage sag, voltage source converter (VSC), phase shift control
Procedia PDF Downloads 33611660 Stability and Performance Improvement of a Two-Degree-of-Freedom Robot under Interaction Using the Impedance Control
Authors: Seyed Reza Mirdehghan, Mohammad Reza Haeri Yazdi
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In this paper, the stability and the performance of a two-degree-of-freedom robot under an interaction with a unknown environment has been investigated. The time when the robot returns to its initial position after an interaction and the primary resistance of the robot against the impact must be reduced. Thus, the applied torque on the motor will be reduced. The impedance control is an appropriate method for robot control in these conditions. The stability of the robot at interaction moment was transformed to be a robust stability problem. The dynamic of the unknown environment was modeled as a weight function and the stability of the robot under an interaction with the environment has been investigated using the robust control concept. To improve the performance of the system, a force controller has been designed which the normalized impedance after interaction has been reduced. The resistance of the robot has been considered as a normalized cost function and its value was 0.593. The results has showed reduction of resistance of the robot against impact and the reduction of convergence time by lower than one second.Keywords: impedance control, control system, robots, interaction
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