Search results for: automatic navigation control
10438 Iterative Estimator-Based Nonlinear Backstepping Control of a Robotic Exoskeleton
Authors: Brahmi Brahim, Mohammad Habibur Rahman, Maarouf Saad, Cristóbal Ochoa Luna
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A repetitive training movement is an efficient method to improve the ability and movement performance of stroke survivors and help them to recover their lost motor function and acquire new skills. The ETS-MARSE is seven degrees of freedom (DOF) exoskeleton robot developed to be worn on the lateral side of the right upper-extremity to assist and rehabilitate the patients with upper-extremity dysfunction resulting from stroke. Practically, rehabilitation activities are repetitive tasks, which make the assistive/robotic systems to suffer from repetitive/periodic uncertainties and external perturbations induced by the high-order dynamic model (seven DOF) and interaction with human muscle which impact on the tracking performance and even on the stability of the exoskeleton. To ensure the robustness and the stability of the robot, a new nonlinear backstepping control was implemented with designed tests performed by healthy subjects. In order to limit and to reject the periodic/repetitive disturbances, an iterative estimator was integrated into the control of the system. The estimator does not need the precise dynamic model of the exoskeleton. Experimental results confirm the robustness and accuracy of the controller performance to deal with the external perturbation, and the effectiveness of the iterative estimator to reject the repetitive/periodic disturbances.Keywords: backstepping control, iterative control, Rehabilitation, ETS-MARSE
Procedia PDF Downloads 28610437 Biological Control of Tuta absoluta (Meyrick) (Lep: Gelechiidae) with Enthomopathogenic Fungi
Authors: Dahliz Abderrahmène, Lakhdari Wassim, Bouchikh Yamina, Hammi Hamida, Soud Adila, M’lik Randa, Benglia Sara
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Devastating insects constitute one of strains for cultivate tomato. Among this vandal insects, the tomato leafminer (T. absoluta), which has been introduced in Algeria constitute a challenge for both agricultures and scientists. Firstly, this insect is introduced without their natural enemies which may reduce their damage. Secondly, this species has developed insecticide resistance to many active matters. To contribute to establish a control strategy for T. absoluta we have mad an inventory for their enthomopathogenic fungi. Two fungi were identified among others taken from adults and pupae. These fungi are Aspergillus flavus and Metarhizium sp. A study was conducted in laboratory to recognize the efficiency of these antagonists. These species had unregistered a mortality mounts of 42% and 56% respectively.Keywords: Tuta absoluta, enthomopathogenic fungi, Aspergillus flavus, Metarhizium sp, control strategy
Procedia PDF Downloads 45510436 Short Association Bundle Atlas for Lateralization Studies from dMRI Data
Authors: C. Román, M. Guevara, P. Salas, D. Duclap, J. Houenou, C. Poupon, J. F. Mangin, P. Guevara
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Diffusion Magnetic Resonance Imaging (dMRI) allows the non-invasive study of human brain white matter. From diffusion data, it is possible to reconstruct fiber trajectories using tractography algorithms. Our previous work consists in an automatic method for the identification of short association bundles of the superficial white matter (SWM), based on a whole brain inter-subject hierarchical clustering applied to a HARDI database. The method finds representative clusters of similar fibers, belonging to a group of subjects, according to a distance measure between fibers, using a non-linear registration (DTI-TK). The algorithm performs an automatic labeling based on the anatomy, defined by a cortex mesh parcelated with FreeSurfer software. The clustering was applied to two independent groups of 37 subjects. The clusters resulting from both groups were compared using a restrictive threshold of mean distance between each pair of bundles from different groups, in order to keep reproducible connections. In the left hemisphere, 48 reproducible bundles were found, while 43 bundles where found in the right hemisphere. An inter-hemispheric bundle correspondence was then applied. The symmetric horizontal reflection of the right bundles was calculated, in order to obtain the position of them in the left hemisphere. Next, the intersection between similar bundles was calculated. The pairs of bundles with a fiber intersection percentage higher than 50% were considered similar. The similar bundles between both hemispheres were fused and symmetrized. We obtained 30 common bundles between hemispheres. An atlas was created with the resulting bundles and used to segment 78 new subjects from another HARDI database, using a distance threshold between 6-8 mm according to the bundle length. Finally, a laterality index was calculated based on the bundle volume. Seven bundles of the atlas presented right laterality (IP_SP_1i, LO_LO_1i, Op_Tr_0i, PoC_PoC_0i, PoC_PreC_2i, PreC_SM_0i, y RoMF_RoMF_0i) and one presented left laterality (IP_SP_2i), there is no tendency of lateralization according to the brain region. Many factors can affect the results, like tractography artifacts, subject registration, and bundle segmentation. Further studies are necessary in order to establish the influence of these factors and evaluate SWM laterality.Keywords: dMRI, hierarchical clustering, lateralization index, tractography
Procedia PDF Downloads 33110435 Hand Controlled Mobile Robot Applied in Virtual Environment
Authors: Jozsef Katona, Attila Kovari, Tibor Ujbanyi, Gergely Sziladi
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By the development of IT systems, human-computer interaction is also developing even faster and newer communication methods become available in human-machine interaction. In this article, the application of a hand gesture controlled human-computer interface is being introduced through the example of a mobile robot. The control of the mobile robot is implemented in a realistic virtual environment that is advantageous regarding the aspect of different tests, parallel examinations, so the purchase of expensive equipment is unnecessary. The usability of the implemented hand gesture control has been evaluated by test subjects. According to the opinion of the testing subjects, the system can be well used, and its application would be recommended on other application fields too.Keywords: human-machine interface (HCI), mobile robot, hand control, virtual environment
Procedia PDF Downloads 29810434 Optimal Dynamic Regime for CO Oxidation Reaction Discovered by Policy-Gradient Reinforcement Learning Algorithm
Authors: Lifar M. S., Tereshchenko A. A., Bulgakov A. N., Guda S. A., Guda A. A., Soldatov A. V.
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Metal nanoparticles are widely used as heterogeneous catalysts to activate adsorbed molecules and reduce the energy barrier of the reaction. Reaction product yield depends on the interplay between elementary processes - adsorption, activation, reaction, and desorption. These processes, in turn, depend on the inlet feed concentrations, temperature, and pressure. At stationary conditions, the active surface sites may be poisoned by reaction byproducts or blocked by thermodynamically adsorbed gaseous reagents. Thus, the yield of reaction products can significantly drop. On the contrary, the dynamic control accounts for the changes in the surface properties and adjusts reaction parameters accordingly. Therefore dynamic control may be more efficient than stationary control. In this work, a reinforcement learning algorithm has been applied to control the simulation of CO oxidation on a catalyst. The policy gradient algorithm is learned to maximize the CO₂ production rate based on the CO and O₂ flows at a given time step. Nonstationary solutions were found for the regime with surface deactivation. The maximal product yield was achieved for periodic variations of the gas flows, ensuring a balance between available adsorption sites and the concentration of activated intermediates. This methodology opens a perspective for the optimization of catalytic reactions under nonstationary conditions.Keywords: artificial intelligence, catalyst, co oxidation, reinforcement learning, dynamic control
Procedia PDF Downloads 13110433 Heterogeneous Artifacts Construction for Software Evolution Control
Authors: Mounir Zekkaoui, Abdelhadi Fennan
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The software evolution control requires a deep understanding of the changes and their impact on different system heterogeneous artifacts. And an understanding of descriptive knowledge of the developed software artifacts is a prerequisite condition for the success of the evolutionary process. The implementation of an evolutionary process is to make changes more or less important to many heterogeneous software artifacts such as source code, analysis and design models, unit testing, XML deployment descriptors, user guides, and others. These changes can be a source of degradation in functional, qualitative or behavioral terms of modified software. Hence the need for a unified approach for extraction and representation of different heterogeneous artifacts in order to ensure a unified and detailed description of heterogeneous software artifacts, exploitable by several software tools and allowing to responsible for the evolution of carry out the reasoning change concerned.Keywords: heterogeneous software artifacts, software evolution control, unified approach, meta model, software architecture
Procedia PDF Downloads 44510432 The Environmental Benefits of the Adoption of Emission Control for Locomotives in Brazil
Authors: Rui de Abrantes, André Luiz Silva Forcetto
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Air pollution is a big problem in many cities around the world. Brazilian big cities also have this problem, where millions of people are exposed daily to pollutants levels above the recommended by WHO. Brazil has taken several actions to reduce air pollution, among others, controlling the atmospheric emissions from vehicles, non-road mobile machinery, and motorcycles, but on the other side, there are no emissions controls for locomotives, which are exposing the population to tons of pollutants annually. The rail network is not homogeneously distributed in the national territory; it is denser near the big cities, and this way, the population is more exposed to pollutants; apart from that, the government intends to increase the rail network as one of the strategies for greenhouse gas mitigation, complying with the international agreements against the climate changes. This paper initially presents the estimated emissions from locomotive fleets with no emission control and with emission control equivalent to US Tier 3 from 2028 and for the next 20 years. However, we realized that a program equivalent to phase Tier 3 would not be effective, so we proposed a program in two steps that will avoid the release of more than 2.4 million tons of CO and 531,000 tons of hydrocarbons, 3.7 million tons of nitrogen oxides, and 102,000 tons of particulate matter in 20 years.Keywords: locomotives, emission control, air pollution, pollutants emission
Procedia PDF Downloads 4910431 Associations between Mindfulness, Temporal Discounting, Locus of Control, and Reward-Based Eating in a Sample of Overweight and Obese Adults
Authors: Andrea S. Badillo-Perez, Alexis D. Mitchell, Sara M. Levens
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Overeating, and obesity have been associated with addictive behavior, primarily due to behaviors like reward-based eating, the tendency to overeat due to factors such as lack of control, preoccupation over food, and lack of satiation. Temporal discounting (TD), the ability to select future rewards over short term gains, and mindfulness, the process of maintaining present moment awareness, have been suggested to have significant, differential impacts on health-related behaviors. An individual’s health locus of control, the degree to which they feel that they have control over their health is also known to have an impact on health outcomes. The goal of this study was to investigate the relationship between health locus of control and reward-based eating, as well as the relation between TD and mindfulness in a sample (N = 126) of overweight or obese participants from larger health-focused study. Through the use of questionnaires (including the Five Facet Mindfulness Questionnaire (FFMQ), Reward-Based Eating Drive (RED), and Multidimensional Health Locus of Control (MHLOC)), anthropometric measurements, and a computerized TD task, a series of regressions tested the association between subscales of these measures. Results revealed differences in how the mindfulness subscales are associated with TD measures. Specifically the ‘Observing’ (beta =-.203) and ‘Describing’ (beta =.26) subscales were associated with lower TD rates and a longer subjective devaluation time-frame respectively. In contrast, the ‘Acting with Awareness’ subscale was associated with a shorter subjective devaluation timeframe (beta =-.23). These findings suggest that the reflective perspective initiated through the observing and describing components of mindfulness may facilitate delay of gratification, whereas the acting with awareness component of mindfulness, which focuses on the present moment, may make delay of gratification more challenging. Results also indicated that a higher degree of reward-based eating was associated with a higher degree of an external health locus of control based on the power of chance (beta =.10). However, an external locus of control based on the power of others had no significant association with reward-based eating. This finding implies that the belief that health is due to chance is associated with greater reward-based eating behavior, suggesting that interventions that focus on locus of control may be helpful. Overall, findings demonstrate that weight loss interventions may benefit from health locus of control and mindfulness exercises, but caution should be taken as the components of mindfulness appear to have different effects on increasing or decreasing delay of gratification.Keywords: health locus of control, mindfulness, obesity, reward-based eating, temporal discounting
Procedia PDF Downloads 13610430 Real Time Data Communication with FlightGear Using Simulink Over a UDP Protocol
Authors: Adil Loya, Ali Haider, Arslan A. Ghaffor, Abubaker Siddique
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Simulation and modelling of Unmanned Aero Vehicle (UAV) has gained wide popularity in front of aerospace community. The demand of designing and modelling optimized control system for UAV has increased ten folds since last decade. The reason is next generation warfare is dependent on unmanned technologies. Therefore, this research focuses on the simulation of nonlinear UAV dynamics on Simulink and its integration with Flightgear. There has been lots of research on implementation of optimizing control using Simulink, however, there are fewer known techniques to simulate these dynamics over Flightgear and a tedious technique of acquiring data has been tackled in this research horizon. Sending data to Flightgear is easy but receiving it from Simulink is not that straight forward, i.e. we can only receive control data on the output. However, in this research we have managed to get the data out from the Flightgear by implementation of level 2 s-function block within Simulink. Moreover, the results captured from Flightgear over a Universal Datagram Protocol (UDP) communication are then compared with the attitude signal that were sent previously. This provide useful information regarding the difference in outputs attained from Simulink to Flightgear. It was found that values received on Simulink were in high agreement with that of the Flightgear output. And complete study has been conducted in a discrete way.Keywords: aerospace, flight control, flightgear, communication, Simulink
Procedia PDF Downloads 28610429 Control of the Pest Bemisia tabaci With the Entomopathogenic Fungus Beauveria bassiana in a Geothermal Greenhouse in Southern Tunisia
Authors: Besma Hamrouni Assadi, Mohamed Sadok Belkadhi
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The whitefly Bemisia tabaci is a cosmopolitan insect that causes serious damage to greenhouse crops. It is increasingly recognized that the use of biological control means such as entomopathogenic fungi presents a sustainable solution to integrated pest management programs. In order to reduce the use of chemical pesticides, Beauveria bassiana strain R444 was tested against eggs and second, third and fourth instar larvae of B. tabaci in a geothermal tomato greenhouse in southern Tunisia. This entomopathogenic fungus was compared to a chemical pesticide Imidacloprid and an untreated control. We found significant mortality of individuals caused by B. bassiana comparable to that caused by the chemical pesticide. After four weeks of follow-up, this fungus causes a mortality of eggs and larvae of B. tabaci that exceeds 60%. It shows that the use of entomopathogenic fungi can help reduce the use of pesticides to control B. tabaci on geothermal crops.Keywords: entomopathogenic fungi, Bemisia tabaci, geothermal greenhouse, integrated pest management programs
Procedia PDF Downloads 10510428 Advanced Mouse Cursor Control and Speech Recognition Module
Authors: Prasad Kalagura, B. Veeresh kumar
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We constructed an interface system that would allow a similarly paralyzed user to interact with a computer with almost full functional capability. A real-time tracking algorithm is implemented based on adaptive skin detection and motion analysis. The clicking of the mouse is activated by the user's eye blinking through a sensor. The keyboard function is implemented by voice recognition kit.Keywords: embedded ARM7 processor, mouse pointer control, voice recognition
Procedia PDF Downloads 57810427 Robust Speed Sensorless Control to Estimated Error for PMa-SynRM
Authors: Kyoung-Jin Joo, In-Gun Kim, Hyun-Seok Hong, Dong-Woo Kang, Ju Lee
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Recently, the permanent magnet-assisted synchronous reluctance motor (PMa-SynRM) that can be substituted for the induction motor has been studying because of the needs of the development of the premium high efficiency motor for the minimum energy performance standard (MEPS). PMa-SynRM is required to the speed and position information for motor speed and torque controls. However, to apply the sensors has many problems that are sensor mounting space shortage and additional cost, etc. Therefore, in this paper, speed-sensorless control based on model reference adaptive system (MRAS) is introduced to eliminate the sensor. The sensorless method is constructed in a reference model as standard and an adaptive model as the state observer. The proposed algorithm is verified by the simulation.Keywords: PMa-SynRM, sensorless control, robust estimation, MRAS method
Procedia PDF Downloads 40410426 Blood Flow Estimator of the Left Ventricular Assist Device Based in Look-Up-Table: In vitro Tests
Authors: Tarcisio F. Leao, Bruno Utiyama, Jeison Fonseca, Eduardo Bock, Aron Andrade
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This work presents a blood flow estimator based in Look-Up-Table (LUT) for control of Left Ventricular Assist Device (LVAD). This device has been used as bridge to transplantation or as destination therapy to treat patients with heart failure (HF). Destination Therapy application requires a high performance LVAD; thus, a stable control is important to keep adequate interaction between heart and device. LVAD control provides an adequate cardiac output while sustaining an appropriate flow and pressure blood perfusion, also described as physiologic control. Because thrombus formation and system reliability reduction, sensors are not desirable to measure these variables (flow and pressure blood). To achieve this, control systems have been researched to estimate blood flow. LVAD used in the study is composed by blood centrifugal pump, control, and power supply. This technique used pump and actuator (motor) parameters of LVAD, such as speed and electric current. Estimator relates electromechanical torque (motor or actuator) and hydraulic power (blood pump) via LUT. An in vitro Mock Loop was used to evaluate deviations between blood flow estimated and actual. A solution with glycerin (50%) and water was used to simulate the blood viscosity with hematocrit 45%. Tests were carried out with variation hematocrit: 25%, 45% and 58% of hematocrit, or 40%, 50% and 60% of glycerin in water solution, respectively. Test with bovine blood was carried out (42% hematocrit). Mock Loop is composed: reservoir, tubes, pressure and flow sensors, and fluid (or blood), beyond LVAD. Estimator based in LUT is patented, number BR1020160068363, in Brazil. Mean deviation is 0.23 ± 0.07 L/min for mean flow estimated. Larger mean deviation was 0.5 L/min considering hematocrit variation. This estimator achieved deviation adequate for physiologic control implementation. Future works will evaluate flow estimation performance in control system of LVAD.Keywords: blood pump, flow estimator, left ventricular assist device, look-up-table
Procedia PDF Downloads 18610425 Relation Between Marital Adjustment and Parenting: The Moderating Effect of Children´s Temperament
Authors: Ester Ato, Maria Angeles Fernández-Vilar, Maria Dolores Galián
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The aim of this work was to analyze the relation between children´s effortful control, marital adjustment and parenting practices in a sample of 345 Spanish children aged between 6 and 8 years. Traditionally, the literature confirms that a higher level of marital conflict has been associated with less effective and less positive parenting, but there are few studies that include the effect that children´s effortful control exert to this relation. To measure marital adjustment, parenting practices and children’s temperament, parents were given the Marital Adjustment Test (MAT), the Spanish version of the PCRI (Parent-Child Relationship Inventory), and the TMCQ (Temperament in Middle Childhood Questionnaire). The results confirmed that higher marital satisfaction predicted more positive parenting practices, whereas lower marital adjustment scores predicted less parenting support and control. Using a statistical modeling approach, we tested a moderation model that revealed the moderating role of effortful control in the relation between marital adjustment and parenting. Concretely, higher marital satisfaction predicts higher parenting communication and involvement, but only in children with low levels of effortful control. Therefore, a difficult temperament interferes in a less negative way in the family system when parents are satisfied and united. And a better self-regulated child predicts more effective parenting practice regardless of the parents´ marital satisfaction. The clinical implications of the present findings should be considered. Specifically, difficult children must be detected and evaluated in community settings, such as school or community programs, in order to take into account the marital adjustment and parenting practices of their parents, and to be able to design adequate family interventions and prevent future pathologizing patterns.Keywords: effortful control, marital adjustment, parenting, moderation
Procedia PDF Downloads 40510424 Hybrid Velocity Control Approach for Tethered Aerial Vehicle
Authors: Lovesh Goyal, Pushkar Dave, Prajyot Jadhav, GonnaYaswanth, Sakshi Giri, Sahil Dharme, Rushika Joshi, Rishabh Verma, Shital Chiddarwar
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With the rising need for human-robot interaction, researchers have proposed and tested multiple models with varying degrees of success. A few of these models performed on aerial platforms are commonly known as Tethered Aerial Systems. These aerial vehicles may be powered continuously by a tether cable, which addresses the predicament of the short battery life of quadcopters. This system finds applications to minimize humanitarian efforts for industrial, medical, agricultural, and service uses. However, a significant challenge in employing such systems is that it necessities attaining smooth and secure robot-human interaction while ensuring that the forces from the tether remain within the standard comfortable range for the humans. To tackle this problem, a hybrid control method that could switch between two control techniques: constant control input and the steady-state solution, is implemented. The constant control approach is implemented when a person is far from the target location, and error is thought to be eventually constant. The controller switches to the steady-state approach when the person reaches within a specific range of the goal position. Both strategies take into account human velocity feedback. This hybrid technique enhances the outcomes by assisting the person to reach the desired location while decreasing the human's unwanted disturbance throughout the process, thereby keeping the interaction between the robot and the subject smooth.Keywords: unmanned aerial vehicle, tethered system, physical human-robot interaction, hybrid control
Procedia PDF Downloads 9810423 Effectiveness of Clinical Practice Guidelines for Jellyfish Stings Treatment at the Emergency Room of Songkhla Hospital Thailand
Authors: Prataksitorn Chonlakan, Tiparat Wongsilarat
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The traditional clinical practice guideline used at the emergency room at Songkhla Hospital in caring for patients who come in contact with jellyfish venom took a long time for the pain to reduce to the level that patients can cope with. To investigate the effectiveness of clinical practice guidelines by comparing the effectiveness of a newly developed clinical practice guideline with the traditional clinical practice guideline in the following aspects: 1) pain reduction, 2) length of pain, 3) the rate of patient’s re-visit, 4) the rate of severe complications such as anaphylactic shock, and cardiac arrest, and death, and 5) patient satisfaction. This study employed a quasi-experimental research design. Thirty subjects were selected with purposive sampling from jellyfish-sting patients who came for treatment at the Emergency Room of Songkhla Hospital. The subjects were divided using random assignment into two groups of 15 each: an experimental group, and the control group. The control group was treated using the traditional clinical practice guideline consisting of rinsing the affected area with 0.9% normal saline, using a cloth soaked with vinegar to press against the affected area, and controlling pain using tramadol or diclofenac intramuscular injection. The data were analyzed using descriptive statistics and paired t-test at the significance level p < 0.05. The results of the study revealed the following. The pain level in the experimental group was significantly lower than that of the control group (the average pain score of the experimental group was 3.46 while that of the control group was 6.33) (p < 0.05).The length of pain in the experimental group was significantly lower than that of the control group (the average length of pain in the experimental group was 48.67 minutes while that of the control group was 105.35 minutes) (p < 0.05). The rate of re-visit within 12 hours in the experimental group was significantly lower than that of the control group (the rate of re-visit within 12 hours of the experimental group was 0.07 while that of the control group was 0.00) (p < 0.05).No severe complications such as anaphylactic shock, and cardiac arrest were found in the two groups of subjects.The rate of satisfaction among the subjects in the experimental group was significantly higher than that of the control group (the rate of satisfaction among the subjects of the experimental group was 90.00 percent while that among the control group was 66.33 percent) (p < 0.05). The newly develop clinical practice guideline could reduce pain and increase satisfaction among jellyfish-sting patients better than the traditional clinical practice guideline.Keywords: effectiveness, clinical practice guideline, jellyfish-sting patients, cardiac arrest
Procedia PDF Downloads 35110422 Effects of Injection of eCG and Oxytocin on Semen Characteristics of Zel Rams in Nonbreeding Season
Authors: Khosro Ghazvinian, Reza Narenji Sani, Touba Khodaiean, Melika Moezifar
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Many previous studies have reported that eCG was effective for completing spermatogenesis. In mice, eCG increased testes weight. In addition, Oxytocin (OT) was important in sperm transition and sperm motility in domestic animals. Peripheral circulation of OT also, was increased during sex incitement and ejaculation The objective of this study was to investigate the effect of IM injection of eCG and OT on semen characteristics in Zel rams in out of breeding season. Eighteen 3-year-old Zel adult rams were randomly divided into five equal groups (control and four treatment groups). 0.9% NaCl (1 ml) was injected IM into each ram in the control group, whereas eCG was administered IM at a single dose of 400 IU and 600 IU to each ram in the two eCG treatment groups and OT was administered IM at a single dose of 5 IU and 10 IU to each ram in the other two OT treatment groups. Semen samples were taken by an electroejaculator from all rams 10 min after the IM injection of 0.9% NaCl, eCG, or OT. eCG did not alter semen volume, and OT did not alter sperm motility or abnormal sperm, in comparison to the control values. Mass activity, sperm motility and total sperm number increased significantly in eCG group compared to the control group; and semen volume, mass activity, total sperm number of the OT treatment groups increased significantly compared to the control group. Exogenous 600 IU eCG and 10 IU OT increase mass activity, total sperm number, lived sperm and sperm concentration in Zel rams.Keywords: eCG, oxytocine, semen characteristics, Zel Ram, nonbreeding season
Procedia PDF Downloads 40410421 A Simple Thermal Control Technique for the First Egyptian Pico Satellite
Authors: Maged Assem Soliman Mossallam
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One of the main prospectives on the demand of space exploration is to reduce the costs and efforts for satellite design. Concerning this issue satellite down scaling attracts space scientists and engineers. Picosatellite is the smallest category of satellites. The overall mass is less than 1 kg and dimensions are 10x10x3 cm3. Thermal control target is to keep the Pico-satellite board temperature within the permissible limits of temperature. Thermal design is completely passive which relies mainly on the enhancement of the thermo-optical properties of aluminum using anodization. Transient analysis is given for two different orbits, ISS orbit and 600 km altitude orbit. Results show that board temperature lies within 3 oC to 22 oC using black anodization which is a permissible limit for the satellite internal electronic board.Keywords: satellite thermal control, small satellites, thermooptical properties , transient orbit analysis
Procedia PDF Downloads 11610420 Cleaner Technology for Stone Crushers
Authors: S. M. Ahuja
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There are about 12000 stone crusher units in India and are located in clusters around urban areas to the stone quarries. These crushers create lot of fugitive dust emissions and noise pollution which is a major health hazard for the people working in the crushers and also living in its vicinity. Ambient air monitoring was carried out near various stone crushers and it has been observed that fugitive emission varied from 300 to 8000 mg/Nm3. A number of stone crushers were thoroughly studied and their existing pollution control devices were examined. Limitations in the existing technology were also studied. A technology consisting of minimal effective spray nozzles to reduce the emissions at source followed by a containment cum control system having modular cyclones as air pollution control device has been conceived. Besides preliminary energy audit has also been carried out in some of the stone crushers which indicates substantial potential for energy saving.Keywords: stone crushers, spray nozzles, energy audit
Procedia PDF Downloads 33210419 Channels Splitting Strategy for Optical Local Area Networks of Passive Star Topology
Authors: Peristera Baziana
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In this paper, we present a network configuration for a WDM LANs of passive star topology that assume that the set of data WDM channels is split into two separate sets of channels, with different access rights over them. Especially, a synchronous transmission WDMA access algorithm is adopted in order to increase the probability of successful transmission over the data channels and consequently to reduce the probability of data packets transmission cancellation in order to avoid the data channels collisions. Thus, a control pre-transmission access scheme is followed over a separate control channel. An analytical Markovian model is studied and the average throughput is mathematically derived. The performance is studied for several numbers of data channels and various values of control phase duration.Keywords: access algorithm, channels division, collisions avoidance, wavelength division multiplexing
Procedia PDF Downloads 29610418 Change of Taste Preference after Bariatric Surgery
Authors: Piotr Tylec, Julia Wierzbicka, Natalia Gajewska, Krzysztof Przeczek, Grzegorz Torbicz, Alicja Dudek, Magdalena Pisarska-Adamczyk, Mateusz Wierdak, Michal Pedziwiatr
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Introduction: Many patients have described changes in taste perception after weight loss surgery. However, little data is available about short term changes in taste after surgery. Aim: We aimed to evaluate short-term changes in taste preference after bariatric surgeries in comparison to colorectal surgeries. Material and Methods: Between April 2018 and April 2019, a total of 121 bariatric patients and 63 controls participated. Bariatric patients underwent laparoscopic sleeve gastrectomy or Roux-en-Y gastric by-pass. Controls underwent oncological colorectal surgeries. Patients who developed clinical complications requiring restriction of oral intake after surgery or withdraw their consent were excluded from the study. In the end, 85 bariatric patients and 44 controls were included. In all of them, the 16-item ERAS Protocol was applied. Using 10-points Numeric Rating Scale (1-10) patients completed questionnaire and rated their appetite and thirst (1 - no appetite/not thirsty, 10 – normal appetite/very thirsty) and flavoured standardized liquids' taste (1- horrible, 10-very tasty) and food images for the 6 group of taste (sweet, umami, sour, spicy, bitter and salty) (1 - not appetizing, 10 - very appetizing) preoperatively and on the first postoperative day. Data were analysed with Statistica 13.0 PL. Results: Analysed group consist of 129 patients (85 bariatric, 44 controls). Mean age and BMI in a research group was 44.91 years old, 46.22 kg/m² and in control group 62.09 years old, 25.87 kg/m², respectively. Our analysis revealed significant differences in changes of appetite between both groups (research: -4.55 ± 3.76 vs. control: -0.85 ± 4.37; p < 0.05), ratings bitter (research: 0.60 ± 2.98 vs. control: -0.88 ± 2.58; p < 0.05) and salty (research: 1.20 ± 3.50 vs. control: -0.52 ± 2.90; p < 0.05) flavoured liquids and ratings for sweet (research: 1.62 ± 3.31 vs. control: 0.01 ± 2.63; p < 0.05) and bitter (research: 1.21 ± 3.15 vs. control: -0.09 ± 2.25; p < 0.05) food images. There were statistically significant results in the ratings of other images, but in comparison to the control group, they were not statistically significant. Conclusion: The study showed that bariatric surgeries quickly decreases appetite and desire to eat certain types of food, such as salty. Moreover, the bitter taste was more desirable in the research group in comparison to control group. Nevertheless, the sweet taste was more appetible in the bariatric group than in control.Keywords: bariatric surgery, general surgery, obesity, taste preference
Procedia PDF Downloads 13510417 USA Commercial Pilots’ Views of Crew Resource Management, Social Desirability, and Safety Locus of Control
Authors: Stephen Vera, Tabitha Black, Charalambos Cleanthous, Ryan Sain
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A gender comparison of USA commercial pilots’ demographics and views of CRM, social desirability and locus of control were surveyed. The Aviation safety locus of control (ASLOC) was used to measure external (ASLOC-E) or internal (ASLOC-I) aviation safety locus of control. The gender differences were explored using the ASLOC scores as a categorical variable. A differential comparison of crew resource management (CRM), based on the Federal Aviation Administration’s (FAA) guidelines was conducted. The results indicated that the proportion of female to male respondents matches the current ratio of USA commercial pilots. Moreover, there were no significant differences regarding overall education and the total number of communication classes one took. Regarding CRM issues, there were no significant differences on their views regarding the roles of the PIC, stress, time management, and managing a flight team. The females scored significantly lower on aeronautical decision making (ADM) and communications. There were no significant differences on either the Balanced Inventory of Desirable Responding (BIDR) impression management (IM) or self-deceptive enhancement (SDE). Although there were no overall significant differences on the ASLOC, the females did score higher on the internal subscale than did the males. An additional comparison of socially desirable responding indicates that all scores may be invalid, especially from the female respondents.Keywords: social desirability, safety locus of control, crew resource management, commercial pilots
Procedia PDF Downloads 25610416 A Coordinate-Based Heuristic Route Search Algorithm for Delivery Truck Routing Problem
Authors: Ahmed Tarek, Ahmed Alveed
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Vehicle routing problem is a well-known re-search avenue in computing. Modern vehicle routing is more focused with the GPS-based coordinate system, as the state-of-the-art vehicle, and trucking systems are equipped with digital navigation. In this paper, a new two dimensional coordinate-based algorithm for addressing the vehicle routing problem for a supply chain network is proposed and explored, and the algorithm is compared with other available, and recently devised heuristics. For the algorithms discussed, which includes the pro-posed coordinate-based search heuristic as well, the advantages and the disadvantages associated with the heuristics are explored. The proposed algorithm is studied from the stand point of a small supermarket chain delivery network that supplies to its stores in four different states around the East Coast area, and is trying to optimize its trucking delivery cost. Minimizing the delivery cost for the supply network of a supermarket chain is important to ensure its business success.Keywords: coordinate-based optimal routing, Hamiltonian Circuit, heuristic algorithm, traveling salesman problem, vehicle routing problem
Procedia PDF Downloads 14710415 A Biomimetic Approach for the Multi-Objective Optimization of Kinetic Façade Design
Authors: Do-Jin Jang, Sung-Ah Kim
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A kinetic façade responds to user requirements and environmental conditions. In designing a kinetic façade, kinetic patterns play a key role in determining its performance. This paper proposes a biomimetic method for the multi-objective optimization for kinetic façade design. The autonomous decentralized control system is combined with flocking algorithm. The flocking agents are autonomously reacting to sensor values and bring about kinetic patterns changing over time. A series of experiments were conducted to verify the potential and limitations of the flocking based decentralized control. As a result, it could show the highest performance balancing multiple objectives such as solar radiation and openness among the comparison group.Keywords: biomimicry, flocking algorithm, autonomous decentralized control, multi-objective optimization
Procedia PDF Downloads 51710414 Hybrid Multipath Congestion Control
Authors: Akshit Singhal, Xuan Wang, Zhijun Wang, Hao Che, Hong Jiang
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Multiple Path Transmission Control Protocols (MPTCPs) allow flows to explore path diversity to improve the throughput, reliability and network resource utilization. However, the existing solutions may discourage users to adopt the solutions in the face of multipath scenario where different paths are charged based on different pricing structures, e.g., WiFi vs cellular connections, widely available for mobile phones. In this paper, we propose a Hybrid MPTCP (H-MPTCP) with a built-in mechanism to incentivize users to use multiple paths with different pricing structures. In the meantime, H-MPTCP preserves the nice properties enjoyed by the state-of-the-art MPTCP solutions. Extensive real Linux implementation results verify that H-MPTCP can indeed achieve the design objectives.Keywords: network, TCP, WiFi, cellular, congestion control
Procedia PDF Downloads 71810413 Mass Media and Tobacco in Bangladesh: An Investigation on the Role of Mass Media in the Light of Tobacco Control
Authors: Tahsina Sadeque Kapil Ahmed
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Context: The tobacco epidemic is one of the biggest public health threats the world has ever faced. Tobacco use is a widespread phenomenon in Bangladesh, and that causes numerous deaths and disabilities in a year. The studies conducted elsewhere have strengthened the evidence that mass media campaigns conducted in the context of comprehensive tobacco control programs can promote quitting and reduce smoking, as well as smokeless tobacco prevalence. Awareness building campaigns in mass-media against tobacco use should be prioritized more, and this paper will be an initiative towards enhancing mass-media’s role in controlling tobacco in Bangladesh. Objective: the main objective of this study is to investigate the role of mass-media in controlling tobacco in Bangladesh. Methods: This is a qualitative study and both primary, as well as secondary data were used where information gathered through the Key Informant Interviews (KIIs) and media contents. The employees of media houses (five national papers, two online news portals and six TV channels) were selected as study respondent. Media Content Analysis is used through the broad range of ‘texts’ from transcripts of interviews and discussions along with the materials like reports, footages, advertisements, talk-shows, articles etc. Results: The study result documented several opinions of discussants where Mass media was found to play a strong role in support of the amended tobacco control law and its implication that could be created public support against tobacco farming, exposing to companies’ tactics and other tobacco control activities. The study results also revealed that in controlling tobacco supply and demand effectively, media has been assisting the government and anti-tobacco activities productively. Majority of the Key Informants opined spontaneously on tobacco control program publicity, organizational interference, and influence of other activities on media. They also emphasized role of media for activities of anti-tobacco organizations, awareness building actions, popularization of tobacco control law and its amendment. Conclusion and Recommendation: The study shows evidence that mass media coverage of tobacco control issues is influencing the context of comprehensive tobacco control programs. To reduce tobacco consumption, along with strict enforcement efforts, media should be used to assist with the implementation of the tobacco control law. A sustained nationwide campaign to educate the masses against the dangers of smoking and smokeless tobacco is needed, and media can play an important role in creating further awareness about the dangers associated with tobacco consumption.Keywords: Bangladesh media, mass media, role of media, tobacco control
Procedia PDF Downloads 21310412 The Uniting Control Lyapunov Functions in Permanent Magnet Synchronous Linear Motor
Authors: Yi-Fei Yang, Nai-Bao He, Shao-Bang Xing
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This study investigates the permanent magnet synchronous linear motor (PMSLM) chaotic motion under the specific physical parameters, the stability and the security of motor-driven system will be unavoidably influenced. Therefore, it is really necessary to investigate the methods of controlling or suppressing chaos in PMSLM. Firstly, we derive a chaotic model of PMSLM in the closed-loop system. Secondly, in order to realize the local asymptotic stabilization of the mechanical subsystem and the global stabilization of the motor-driven system including electrical subsystem, we propose an improved uniting control lyapunov functions by introducing backstepping approach. Finally, an illustrated example is also given to show the electiveness of the obtained results.Keywords: linear motor, lyapunov functions, chao control, hybrid controller
Procedia PDF Downloads 33810411 Backstepping Controller for a Variable Wind Speed Energy Conversion System Based on a DFIG
Authors: Sara Mensou, Ahmed Essadki, Issam Minka, Tamou Nasser, Badr Bououlid Idrissi
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In this paper we present a contribution for the modeling and control of wind energy conversion system based on a Doubly Fed Induction Generator (DFIG). Since the wind speed is random the system has to produce an optimal electrical power to the Network and ensures important strength and stability. In this work, the Backstepping controller is used to control the generator via two converter witch placed a DC bus capacitor and connected to the grid by a Filter R-L, in order to optimize capture wind energy. All is simulated and presented under MATLAB/Simulink Software to show performance and robustness of the proposed controller.Keywords: wind turbine, doubly fed induction generator, MPPT control, backstepping controller, power converter
Procedia PDF Downloads 18910410 Bank Internal Controls and Credit Risk in Europe: A Quantitative Measurement Approach
Authors: Ellis Kofi Akwaa-Sekyi, Jordi Moreno Gené
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Managerial actions which negatively profile banks and impair corporate reputation are addressed through effective internal control systems. Disregard for acceptable standards and procedures for granting credit have affected bank loan portfolios and could be cited for the crises in some European countries. The study intends to determine the effectiveness of internal control systems, investigate whether perceived agency problems exist on the part of board members and to establish the relationship between internal controls and credit risk among listed banks in the European Union. Drawing theoretical support from the behavioural compliance and agency theories, about seventeen internal control variables (drawn from the revised COSO framework), bank-specific, country, stock market and macro-economic variables will be involved in the study. A purely quantitative approach will be employed to model internal control variables covering the control environment, risk management, control activities, information and communication and monitoring. Panel data from 2005-2014 on listed banks from 28 European Union countries will be used for the study. Hypotheses will be tested and the Generalized Least Squares (GLS) regression will be run to establish the relationship between dependent and independent variables. The Hausman test will be used to select whether random or fixed effect model will be used. It is expected that listed banks will have sound internal control systems but their effectiveness cannot be confirmed. A perceived agency problem on the part of the board of directors is expected to be confirmed. The study expects significant effect of internal controls on credit risk. The study will uncover another perspective of internal controls as not only an operational risk issue but credit risk too. Banks will be cautious that observing effective internal control systems is an ethical and socially responsible act since the collapse (crisis) of financial institutions as a result of excessive default is a major contagion. This study deviates from the usual primary data approach to measuring internal control variables and rather models internal control variables in a quantitative approach for the panel data. Thus a grey area in approaching the revised COSO framework for internal controls is opened for further research. Most bank failures and crises could be averted if effective internal control systems are religiously adhered to.Keywords: agency theory, credit risk, internal controls, revised COSO framework
Procedia PDF Downloads 31610409 Sustainability and Promotion of Inland Waterway Transportation Projects in Colombia: Case of the Magdalena River
Authors: David Julian Bernal Melgarejo
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Inland Waterway Transportation (IWT) is playing an important role in national transport systems, water transportation is considered to be safe, energy efficient and environmentally friendly mode of transport, considering all the benefits of IWT the Colombian government is planning to restore the Magdalena’s River navigability, embrace waterway transportation in Colombia could strength competitiveness while reduce most of the transport externalities. However, the current situation of the Magdalena deplorable, the most important river of Colombia has been abandoned for decades and the solution is beyond of a single administrative entity. This paper analyzes the outcomes of the Navigation And Inland Waterway Action and Development in Europe (NAIADES) program as a prospective to develop a sustainable program in Colombia. In order to guarantee the long-term future, and the adaptability of the program a research based on individual interviews with stakeholders and policy experts were carried out, findings support the idea of lack of integration within governmental institution, develop marketing strategies and human resources.Keywords: inland waterway transportation, logistics, sustainability, multimodal transport systems, water transportation
Procedia PDF Downloads 475