Search results for: vertical grade
1660 Planktivorous Fish Schooling Responses to Current at Natural and Artificial Reefs
Authors: Matthew Holland, Jason Everett, Martin Cox, Iain Suthers
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High spatial-resolution distribution of planktivorous reef fish can reveal behavioural adaptations to optimise the balance between feeding success and predator avoidance. We used a multi-beam echosounder to record bathymetry and the three-dimensional distribution of fish schools associated with natural and artificial reefs. We utilised generalised linear models to assess the distribution, orientation, and aggregation of fish schools relative to the structure, vertical relief, and currents. At artificial reefs, fish schooled more closely to the structure and demonstrated a preference for the windward side, particularly when exposed to strong currents. Similarly, at natural reefs fish demonstrated a preference for windward aspects of bathymetry, particularly when associated with high vertical relief. Our findings suggest that under conditions with stronger current velocity, fish can exercise their preference to remain close to structure for predator avoidance, while still receiving an adequate supply of zooplankton delivered by the current. Similarly, when current velocity is low, fish tend to disperse for better access to zooplankton. As artificial reefs are generally deployed with the goal of creating productivity rather than simply attracting fish from elsewhere, we advise that future artificial reefs be designed as semi-linear arrays perpendicular to the prevailing current, with multiple tall towers. This will facilitate the conversion of dispersed zooplankton into energy for higher trophic levels, enhancing reef productivity and fisheries.Keywords: artificial reef, current, forage fish, multi-beam, planktivorous fish, reef fish, schooling
Procedia PDF Downloads 1581659 Numerical Performance Evaluation of a Savonius Wind Turbines Using Resistive Torque Modeling
Authors: Guermache Ahmed Chafik, Khelfellah Ismail, Ait-Ali Takfarines
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The Savonius vertical axis wind turbine is characterized by sufficient starting torque at low wind speeds, simple design and does not require orientation to the wind direction; however, the developed power is lower than other types of wind turbines such as Darrieus. To increase these performances several studies and researches have been developed, such as optimizing blades shape, using passive controls and also minimizing power losses sources like the resisting torque due to friction. This work aims to estimate the performance of a Savonius wind turbine introducing a User Defined Function to the CFD model analyzing resisting torque. This User Defined Function is developed to simulate the action of the wind speed on the rotor; it receives the moment coefficient as an input to compute the rotational velocity that should be imposed on computational domain rotating regions. The rotational velocity depends on the aerodynamic moment applied on the turbine and the resisting torque, which is considered a linear function. Linking the implemented User Defined Function with the CFD solver allows simulating the real functioning of the Savonius turbine exposed to wind. It is noticed that the wind turbine takes a while to reach the stationary regime where the rotational velocity becomes invariable; at that moment, the tip speed ratio, the moment and power coefficients are computed. To validate this approach, the power coefficient versus tip speed ratio curve is compared with the experimental one. The obtained results are in agreement with the available experimental results.Keywords: resistant torque modeling, Savonius wind turbine, user-defined function, vertical axis wind turbine performances
Procedia PDF Downloads 1551658 Impact of a Novel Technique of S-Shaped Tracheostoma in Pediatric Tracheostomy in Intensive Care Unit on Success and Procedure Related Complications
Authors: Devendra Gupta, Sushilk K. Agarwal, Amit Kesari, P. K. Singh
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Objectives: Pediatric patients often may experience persistent respiratory failure that requires tracheostomy placement in Pediatric ICU. We have designed a technique of tracheostomy in pediatric patients with S-shaped incision on the tracheal wall with higher success rate and lower complication rate. Technique: Following general anesthesia and positioning of the patient, the trachea was exposed in midline by a vertical skin incision. In order to make S-shaped tracheostoma, second tracheal ring was identified. The conventional vertical incision was made in second tracheal ring and then extended at both its ends laterally in the inter-cartilaginous space parallel to the tracheal cartilage in the opposite direction to make the incision S-shaped. The trachea was dilated with tracheal dilator and appropriate size of tracheostomy tube was then placed into the trachea. Results: S-shaped tracheostomy was performed in 20 children with mean age of 6.25 years (age range is 2-7) requiring tracheostomy placement. The tracheostomy tubes were successfully placed in all the patients in single attempt. There was no incidence of significant intra-operative bleeding, subcutaneous emphysema, vocal cord palsy or pneumothorax. Two patients developed pneumonia and expired within a year. However, there was no incidence of tracheo-esophageal fistula, suprastomal collapse or difficulty in decannulation on one year of follow up related to our technique. One patient developed late trachietis managed conservatively. Conclusion: S-shaped tracheoplasty was associated with high success rate, reduced risk of the early and late complications in pediatric patients requiring tracheostomy.Keywords: peatrics, tracheostomy, ICU, tracheostoma
Procedia PDF Downloads 2641657 Risk Assessment of Flood Defences by Utilising Condition Grade Based Probabilistic Approach
Authors: M. Bahari Mehrabani, Hua-Peng Chen
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Management and maintenance of coastal defence structures during the expected life cycle have become a real challenge for decision makers and engineers. Accurate evaluation of the current condition and future performance of flood defence structures is essential for effective practical maintenance strategies on the basis of available field inspection data. Moreover, as coastal defence structures age, it becomes more challenging to implement maintenance and management plans to avoid structural failure. Therefore, condition inspection data are essential for assessing damage and forecasting deterioration of ageing flood defence structures in order to keep the structures in an acceptable condition. The inspection data for flood defence structures are often collected using discrete visual condition rating schemes. In order to evaluate future condition of the structure, a probabilistic deterioration model needs to be utilised. However, existing deterioration models may not provide a reliable prediction of performance deterioration for a long period due to uncertainties. To tackle the limitation, a time-dependent condition-based model associated with a transition probability needs to be developed on the basis of condition grade scheme for flood defences. This paper presents a probabilistic method for predicting future performance deterioration of coastal flood defence structures based on condition grading inspection data and deterioration curves estimated by expert judgement. In condition-based deterioration modelling, the main task is to estimate transition probability matrices. The deterioration process of the structure related to the transition states is modelled according to Markov chain process, and a reliability-based approach is used to estimate the probability of structural failure. Visual inspection data according to the United Kingdom Condition Assessment Manual are used to obtain the initial condition grade curve of the coastal flood defences. The initial curves then modified in order to develop transition probabilities through non-linear regression based optimisation algorithms. The Monte Carlo simulations are then used to evaluate the future performance of the structure on the basis of the estimated transition probabilities. Finally, a case study is given to demonstrate the applicability of the proposed method under no-maintenance and medium-maintenance scenarios. Results show that the proposed method can provide an effective predictive model for various situations in terms of available condition grading data. The proposed model also provides useful information on time-dependent probability of failure in coastal flood defences.Keywords: condition grading, flood defense, performance assessment, stochastic deterioration modelling
Procedia PDF Downloads 2331656 Low-Cost Monitoring System for Hydroponic Urban Vertical Farms
Authors: Francesco Ruscio, Paolo Paoletti, Jens Thomas, Paul Myers, Sebastiano Fichera
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This paper presents the development of a low-cost monitoring system for a hydroponic urban vertical farm, enabling its automation and a quantitative assessment of the farm performance. Urban farming has seen increasing interest in the last decade thanks to the development of energy efficient and affordable LED lights; however, the optimal configuration of such systems (i.e. amount of nutrients, light-on time, ambient temperature etc.) is mostly based on the farmers’ experience and empirical guidelines. Moreover, even if simple, the maintenance of such systems is labor intensive as it requires water to be topped-up periodically, mixing of the nutrients etc. To unlock the full potential of urban farming, a quantitative understanding of the role that each variable plays in the growth of the plants is needed, together with a higher degree of automation. The low-cost monitoring system proposed in this paper is a step toward filling this knowledge and technological gap, as it enables collection of sensor data related to water and air temperature, water level, humidity, pressure, light intensity, pH and electric conductivity without requiring any human intervention. More sensors and actuators can also easily be added thanks to the modular design of the proposed platform. Data can be accessed remotely via a simple web interface. The proposed platform can be used both for quantitatively optimizing the setup of the farms and for automating some of the most labor-intensive maintenance activities. Moreover, such monitoring system can also potentially be used for high-level decision making, once enough data are collected.Keywords: automation, hydroponics, internet of things, monitoring system, urban farming
Procedia PDF Downloads 1601655 Geophysical Methods of Mapping Groundwater Aquifer System: Perspectives and Inferences From Lisana Area, Western Margin of the Central Main Ethiopian Rift
Authors: Esubalew Yehualaw Melaku, Tigistu Haile Eritro
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In this study, two basic geophysical methods are applied for mapping the groundwater aquifer system in the Lisana area along the Guder River, northeast of Hosanna town, near the western margin of the Central Main Ethiopian Rift. The main target of the study is to map the potential aquifer zone and investigate the groundwater potential for current and future development of the resource in the Gode area. The geophysical methods employed in this study include, Vertical Electrical Sounding (VES) and magnetic survey techniques. Electrical sounding was used to examine and map the depth to the potential aquifer zone of the groundwater and its distribution over the area. On the other hand, a magnetic survey was used to delineate contact between lithologic units and geological structures. The 2D magnetic modeling and the geoelectric sections are used for the identification of weak zones, which control the groundwater flow and storage system. The geophysical survey comprises of twelve VES readings collected by using a Schlumberger array along six profile lines and more than four hundred (400) magnetic readings at about 10m station intervals along four profiles and 20m along three random profiles. The study result revealed that the potential aquifer in the area is obtained at a depth range from 45m to 92m. This is the response of the highly weathered/ fractured ignimbrite and pumice layer with sandy soil, which is the main water-bearing horizon. Overall, in the neighborhood of four VES points, VES- 2, VES- 3, VES-10, and VES-11, shows good water-bearing zones in the study area.Keywords: vertical electrical sounding, magnetic survey, aquifer, groundwater potential
Procedia PDF Downloads 791654 Ion Beam Polishing of Si in W/Si Multilayer X-Ray Analyzers
Authors: Roman Medvedev, Andrey Yakshin, Konstantin Nikolaev, Sergey Yakunin, Fred Bijkerk
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Multilayer structures are used as spectroscopic elements in fluorescence analysis. These serve the purpose of analyzing soft x-ray emission spectra of materials upon excitation by x-rays or electrons. The analysis then allows quantitative determination of the x-ray emitting elements in the materials. Shorter wavelength range for this application, below 2.5nm, can be covered by using short period multilayers, with a period of 2.5 nm and lower. Thus the detrimental effect on the reflectivity of morphological roughness between materials of the multilayers becomes increasingly pronounced. Ion beam polishing was previously shown to be effective in reducing roughness in some multilayer systems with Si. In this work, we explored W/Si multilayers with the period of 2.5 nm. Si layers were polishing by Ar ions, employing low energy ions, 100 and 80 eV, with the etched Si thickness being in the range 0.1 to 0.5 nm. CuK X-ray diffuse scattering measurements revealed a significant reduction in the diffused scattering in the polished multilayers. However, Grazing Incidence CuK X-ray showed only a marginal reduction of the overall roughness of the systems. Still, measurements of the structures with Grazing Incidence Small Angle X-ray scattering indicated that the vertical correlation length of roughness was strongly reduced in the polished multilayers. These results together suggest that polishing results in the reduction of the vertical propagation of roughness from layer to layer, while only slightly affecting the overall roughness. This phenomenon can be explained by ion-induced surface roughening inherently present in the ion polishing methods. Alternatively, ion-induced densification of thin Si films should also be considered. Finally, the reflectivity of 40% at 0.84 nm at grazing incidence of 9 degrees has been obtained in this work for W/Si multilayers. Analysis of the obtained results is expected to lead to further progress in reflectance.Keywords: interface roughness, ion polishing, multilayer structures, W/Si
Procedia PDF Downloads 1341653 Multiple Negative-Differential Resistance Regions Based on AlN/GaN Resonant Tunneling Structures by the Vertical Growth of Molecular Beam Epitaxy
Authors: Yao Jiajia, Wu Guanlin, LIU Fang, Xue Junshuai, Zhang Jincheng, Hao Yue
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Resonant tunneling diodes (RTDs) based on GaN have been extensively studied. However, no results of multiple logic states achieved by RTDs were reported by the methods of epitaxy in the GaN materials. In this paper, the multiple negative-differential resistance regions by combining two discrete double-barrier RTDs in series have been first demonstrated. Plasma-assisted molecular beam epitaxy (PA-MBE) was used to grow structures consisting of two vertical RTDs. The substrate was a GaN-on-sapphire template. Each resonant tunneling structure was composed of a double barrier of AlN and a single well of GaN with undoped 4-nm space layers of GaN on each side. The AlN barriers were 1.5 nm thick, and the GaN well was 2 nm thick. The resonant tunneling structures were separated from each other by 30-nm thick n+ GaN layers. The bottom and top layers of the structures, grown neighboring to the spacer layers that consist of 200-nm-thick n+ GaN. These devices with two tunneling structures exhibited uniform peaks and valleys current and also had two negative differential resistance NDR regions equally spaced in bias voltage. The current-voltage (I-V) characteristics of resonant tunneling structures with diameters of 1 and 2 μm were analyzed in this study. These structures exhibit three stable operating points, which are investigated in detail. This research demonstrates that using molecular beam epitaxy MBE to vertically grow multiple resonant tunneling structures is a promising method for achieving multiple negative differential resistance regions and stable logic states. These findings have significant implications for the development of digital circuits capable of multi-value logic, which can be achieved with a small number of devices.Keywords: GaN, AlN, RTDs, MBE, logic state
Procedia PDF Downloads 921652 Development of a System for Measuring the Three-axis Pedal Force in Cycling and Its Applications
Authors: Joo-Hack Lee, Jin-Seung Choi, Dong-Won Kang, Jeong-Woo Seo, Ju-Young Kim, Dae-Hyeok Kim, Seung-Tae Yang, Gye-Rae Tack
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For cycling, the analysis of the pedal force is one of the important factors in the study of exercise ability assessment and overuse injuries. In past studies, a two-axis measurement sensor was used at the sagittal plane to measure the force only in the anterior, posterior, and vertical directions and to analyze the loss of force and the injury on the frontal plane due to the forces in the right and left directions. In this study, which is a basic study on diverse analyses of the pedal force that consider the forces on the sagittal plane and the frontal plane, a three-axis pedal force measurement sensor was developed to measure the anterior-posterior (Fx), medio-lateral (Fz), and vertical (Fy) forces. The sensor was fabricated with a size and shape similar to those of the general flat pedal, and had a 550g weight that allowed smooth pedaling. Its measurement range was ±1000 N for Fx and Fz and ±2000 N for Fy, and its non-linearity, hysteresis, and repeatability were approximately 0.5%. The data were sampled at 1000 Hz using a signal collector. To use the developed sensor, the pedaling efficiency (index of efficiency, IE) and the range of left and right (medio-lateral, ML) forces were measured with two seat heights (low and high). The results of the measurement showed that the IE was higher and the force range in the ML direction was lower with the high position than with the low position. The developed measurement sensor and its application results will be useful in understanding and explaining the complicated pedaling technique, and will enable diverse kinematic analyses of the pedal force on the sagittal plane and the frontal plane.Keywords: cycling, pedal force, index of effectiveness, measuring
Procedia PDF Downloads 6611651 Nanomechanical Characterization of Healthy and Tumor Lung Tissues at Cell and Extracellular Matrix Level
Authors: Valeria Panzetta, Ida Musella, Sabato Fusco, Paolo Antonio Netti
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The study of the biophysics of living cells drew attention to the pivotal role of the cytoskeleton in many cell functions, such as mechanics, adhesion, proliferation, migration, differentiation and neoplastic transformation. In particular, during the complex process of malignant transformation and invasion cell cytoskeleton devolves from a rigid and organized structure to a more compliant state, which confers to the cancer cells a great ability to migrate and adapt to the extracellular environment. In order to better understand the malignant transformation process from a mechanical point of view, it is necessary to evaluate the direct crosstalk between the cells and their surrounding extracellular matrix (ECM) in a context which is close to in vivo conditions. In this study, human biopsy tissues of lung adenocarcinoma were analyzed in order to define their mechanical phenotype at cell and ECM level, by using particle tracking microrheology (PTM) technique. Polystyrene beads (500 nm) were introduced into the sample slice. The motion of beads was obtained by tracking their displacements across cell cytoskeleton and ECM structures and mean squared displacements (MSDs) were calculated from bead trajectories. It has been already demonstrated that the amplitude of MSD is inversely related to the mechanical properties of intracellular and extracellular microenvironment. For this reason, MSDs of particles introduced in cytoplasm and ECM of healthy and tumor tissues were compared. PTM analyses showed that cancerous transformation compromises mechanical integrity of cells and extracellular matrix. In particular, the MSD amplitudes in cells of adenocarcinoma were greater as compared to cells of normal tissues. The increased motion is probably associated to a less structured cytoskeleton and consequently to an increase of deformability of cells. Further, cancer transformation is also accompanied by extracellular matrix stiffening, as confirmed by the decrease of MSDs of matrix in tumor tissue, a process that promotes tumor proliferation and invasiveness, by activating typical oncogenic signaling pathways. In addition, a clear correlation between MSDs of cells and tumor grade was found. MSDs increase when tumor grade passes from 2 to 3, indicating that cells undergo to a trans-differentiation process during tumor progression. ECM stiffening is not dependent on tumor grade, but the tumor stage resulted to be strictly correlated with both cells and ECM mechanical properties. In fact, a greater stage is assigned to tumor spread to regional lymph nodes and characterized by an up-regulation of different ECM proteins, such as collagen I fibers. These results indicate that PTM can be used to get nanomechanical characterization at different scale levels in an interpretative and diagnostic context.Keywords: cytoskeleton, extracellular matrix, mechanical properties, particle tracking microrheology, tumor
Procedia PDF Downloads 2791650 Making Beehives More 'Intelligent'- The Case of Capturing, Reducing, and Managing Bee Pest Infestation in Hives through Modification of Hive Entrance Holes and the Installation of Multiple In-Hive Bee Pest Traps
Authors: Prince Amartey
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Bees are clever creatures, thus, capturing bees implies that the hives are intelligent in the sense that they have all of the required circumstances to attract and trap the bees. If the hive goes above and beyond to keep the bees in the hive and to keep the activities of in-hive pests to a minimal in order for the bees to develop to their maximum potential, the hive is becoming or is more 'intelligent'. Some bee pests, such as tiny beehive beetles, are endemic to Africa; however, the way we now extract honey by cutting off the combs and pressing for honey prevents the spread of these bees' insect enemies. However, when we explore entering the commercialization. When freshly collected combs are returned to the hives following the adoption of the frame and other systems, there is a need to consider putting in strategies to manage the accompanying pest concerns that arise with unprotected combs.The techniques for making hives more'intelligent' are thus more important presently, given that the African apicultural business does not wish to encourage the use of pesticides in the hives. This include changing the hive's entrance holes in order to improve the bees' own mechanism for defending the entry sites, as well as collecting pests by setting exterior and in-hive traps to prevent pest infiltration into hives by any means feasible. Material and Methods: The following five (5) mechanisms are proposed to make the hives more 'intelligent.' i. The usage of modified frames with five (5) beetle traps positioned horizontally on the vertical 'legs' to catch the beetle along the combs' surfaces-multiple bee ii. Baited bioelectric frame traps, which has both vertical sections of frame covered with a 3mm mesh that allows pest entry but not bees. The pest is attracted by strips of combs of honey, open brood, pollen on metal plates inserted horizontally on the vertical ‘legs’ of the frames. An electrical ‘mine’ system in place that electrocutes the pests as they step on the wires in the trap to enter the frame trap iii. The ten rounded hive entry holes are adapted as the bees are able to police the entrance to prevent entry of pest. The holes are arranged in two rows, with one on top of the other What Are the Main Contributions of Your Research?-Results Discussions and Conclusions The techniques implemented decrease pest ingress, while in-hive traps capture those that escape entry into the hives. Furthermore, the stand alteration traps larvae and stops their growth into adults. As beekeeping commercialization grows throughout Africa, these initiatives will minimize insect infestation in hives and necessarily enhance honey output.Keywords: bee pests, modified frames, multiple beetle trap, Baited bioelectric frame traps
Procedia PDF Downloads 781649 Optimization of Digestive Conditions of Opuntia ficus-indica var. Saboten using Food-Grade Enzymes
Authors: Byung Wook Yang, Sae Kyul Kim, Seung Il Ahn, Jae Hee Choi, Heejung Jung, Yejin Choi, Byung Yong Kim, Young Tae Hahm
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Opuntia ficus-indica is a member of the Cactaceae family that is widely grown in all the semiarid countries throughout the world. Opuntia ficus-indica var. Saboten (OFS), commonly known as prickly pear cactus, is commercially cultivated as a dietary foodstuffs and medicinal stuffs in Jeju Island, Korea. Owing to high viscosity of OFS’ pad, its application to the commercial field has been limited. When the low viscosity of OFS’s pad is obtained, it is useful for the manufacture of healthy food in the related field. This study was performed to obtain the optimal digestion conditions of food-grade enzymes (Pectinex, Viscozyme and Celluclast) with the powder of OFS stem. And also, the contents of water-soluble dietary fiber (WSDF) of the dried powder prepared by the extraction of OFS stem were monitored and optimized using the response surface methodology (RSM), which included 20 experimental points with 3 replicates for two independent variables (fermentation temperature and time). A central composite design was used to monitor the effect of fermentation temperature (30-90 °C, X1) and fermentation time (1-10h, X2) on dependent variables, such as viscosity (Y1), water-soluble dietary fiber (Y2) and dietary fiber yield (Y3). Estimated maximum values at predicted optimum conditions were in agreement with experimental values. Optimum temperature and duration were 50°C and 12 hours, respectively. Viscosity value reached 3.4 poise. Yield of water-soluble dietary fiber is determined in progress.Keywords: Opuntia ficus-indica var. saboten, enzymatic fermentation, response surface methodology, water-soluble dietary fiber, viscosity
Procedia PDF Downloads 3461648 Evolution and Merging of Double-Diffusive Layers in a Vertically Stable Compositional Field
Authors: Ila Thakur, Atul Srivastava, Shyamprasad Karagadde
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The phenomenon of double-diffusive convection is driven by density gradients created by two different components (e.g., temperature and concentration) having different molecular diffusivities. The evolution of horizontal double-diffusive layers (DDLs) is one of the outcomes of double-diffusive convection occurring in a laterally/vertically cooled rectangular cavity having a pre-existing vertically stable composition field. The present work mainly focuses on different characteristics of the formation and merging of double-diffusive layers by imposing lateral/vertical thermal gradients in a vertically stable compositional field. A CFD-based twodimensional fluent model has been developed for the investigation of the aforesaid phenomena. The configuration containing vertical thermal gradients shows the evolution and merging of DDLs, where, elements from the same horizontal plane move vertically and mix with surroundings, creating a horizontal layer. In the configuration of lateral thermal gradients, a specially oriented convective roll was found inside each DDL and each roll was driven by the competing density change due to the already existing composition field and imposed thermal field. When the thermal boundary layer near the vertical wall penetrates the salinity interface, it can disrupt the compositional interface and can lead to layer merging. Different analytical scales were quantified and compared for both configurations. Various combinations of solutal and thermal Rayleigh numbers were investigated to get three different regimes, namely; stagnant regime, layered regime and unicellular regime. For a particular solutal Rayleigh number, a layered structure can originate only for a range of thermal Rayleigh numbers. Lower thermal Rayleigh numbers correspond to a diffusion-dominated stagnant regime. Very high thermal Rayleigh corresponds to a unicellular regime with high convective mixing. Different plots identifying these three regimes, number, thickness and time of existence of DDLs have been studied and plotted. For a given solutal Rayleigh number, an increase in thermal Rayleigh number increases the width but decreases both the number and time of existence of DDLs in the fluid domain. Sudden peaks in the velocity and heat transfer coefficient have also been observed and discussed at the time of merging. The present study is expected to be useful in correlating the double-diffusive convection in many large-scale applications including oceanography, metallurgy, geology, etc. The model has also been developed for three-dimensional geometry, but the results were quite similar to that of 2-D simulations.Keywords: double diffusive layers, natural convection, Rayleigh number, thermal gradients, compositional gradients
Procedia PDF Downloads 841647 Assessing the Legacy Effects of Wildfire on Eucalypt Canopy Structure of South Eastern Australia
Authors: Yogendra K. Karna, Lauren T. Bennett
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Fire-tolerant eucalypt forests are one of the major forest ecosystems of south-eastern Australia and thought to be highly resistant to frequent high severity wildfires. However, the impact of different severity wildfires on the canopy structure of fire-tolerant forest type is under-studied, and there are significant knowledge gaps in relation to the assessment of tree and stand level canopy structural dynamics and recovery after fire. Assessment of canopy structure is a complex task involving accurate measurements of the horizontal and vertical arrangement of the canopy in space and time. This study examined the utility of multitemporal, small-footprint lidar data to describe the changes in the horizontal and vertical canopy structure of fire-tolerant eucalypt forests seven years after wildfire of different severities from the tree to stand level. Extensive ground measurements were carried out in four severity classes to describe and validate canopy cover and height metrics as they change after wildfire. Several metrics such as crown height and width, crown base height and clumpiness of crown were assessed at tree and stand level using several individual tree top detection and measurement algorithm. Persistent effects of high severity fire 8 years after both on tree crowns and stand canopy were observed. High severity fire increased the crown depth but decreased the crown projective cover leading to more open canopy.Keywords: canopy gaps, canopy structure, crown architecture, crown projective cover, multi-temporal lidar, wildfire severity
Procedia PDF Downloads 1751646 Seismological Studies in Some Areas in Egypt
Authors: Gamal Seliem, Hassan Seliem
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Aswan area is one of the important areas in Egypt and because it encompasses the vital engineering structure of the High dam, so it has been selected for the present study. The study of the crustal deformation and gravity associated with earthquake activity in the High Dam area of great importance for the safety of the High Dam and its economic resources. This paper deals with using micro-gravity, precise leveling and GPS data for geophysical and geodetically studies. For carrying out the detailed gravity survey in the area, were established for studying the subsurface structures. To study the recent vertical movements, a profile of 10 km length joins the High Dam and Aswan old dam were established along the road connecting the two dams. This profile consists of 35 GPS/leveling stations extending along the two sides of the road and on the High Dam body. Precise leveling was carried out with GPS and repeated micro-gravity survey in the same time. GPS network consisting of nine stations was established for studying the recent crustal movements. Many campaigns from December 2001 to December 2014 were performed for collecting the gravity, leveling and GPS data. The main aim of this work is to study the structural features and the behavior of the area, as depicted from repeated micro-gravity, precise leveling and GPS measurements. The present work focuses on the analysis of the gravity, leveling and GPS data. The gravity results of the present study investigate and analyze the subsurface geologic structures and reveal to there be minor structures; features and anomalies are taking W-E and N-S directions. The geodetic results indicated lower rates of the vertical and horizontal displacements and strain values. This may be related to the stability of the area.Keywords: repeated micro-gravity changes, precise leveling, GPS data, Aswan High Dam
Procedia PDF Downloads 4481645 Locus of Control, Metacognitive Knowledge, Metacognitive Regulation, and Student Performance in an Introductory Economics Course
Authors: Ahmad A. Kader
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In the principles of Microeconomics course taught during the Fall Semester 2019, 158out of 179 students participated in the completion of two questionnaires and a survey describing their demographic and academic profiles. The two questionnaires include the 29 items of the Rotter Locus of Control Scale and the 52 items of the Schraw andDennisonMetacognitive Awareness Scale. The 52 items consist of 17 items describing knowledge of cognition and 37 items describing the regulation of cognition. The paper is intended to show the combined influence of locus of control, metacognitive knowledge, and metacognitive regulation on student performance. The survey covers variables that have been tested and recognized in economic education literature, which include GPA, gender, age, course level, race, student classification, whether the course was required or elective, employments, whether a high school economic course was taken, and attendance. Regression results show that of the economic education variables, GPA, classification, whether the course was required or elective, and attendance are the only significant variables in their influence on student grade. Of the educational psychology variables, the regression results show that the locus of control variable has a negative and significant effect, while the metacognitive knowledge variable has a positive and significant effect on student grade. Also, the adjusted R square value increased markedly with the addition of the locus of control, metacognitive knowledge, and metacognitive regulation variables to the regression equation. The t test results also show that students who are internally oriented and are high on the metacognitive knowledge scale significantly outperform students who are externally oriented and are low on the metacognitive knowledge scale. The implication of these results for educators is discussed in the paper.Keywords: locus of control, metacognitive knowledge, metacognitive regulation, student performance, economic education
Procedia PDF Downloads 1201644 A Standard-Based Competency Evaluation Scale for Preparing Qualified Adapted Physical Education Teachers
Authors: Jiabei Zhang
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Although adapted physical education (APE) teacher preparation programs are available in the nation, a consistent standards-based competency evaluation scale for preparing of qualified personnel for teaching children with disabilities in APE cannot be identified in the literature. The purpose of this study was to develop a standard-based competency evaluation scale for assessing qualifications for teaching children with disabilities in APE. Standard-based competencies were reviewed and identified based on research evidence documented as effective in teaching children with disabilities in APE. A standard-based competency scale was developed for assessing qualifications for teaching children with disabilities in APE. This scale included 20 standard-based competencies and a 4-point Likert-type scale for each standard-based competency. The first standard-based competency is knowledgeable of the causes of disabilities and their effects. The second competency is the ability to assess physical education skills of children with disabilities. The third competency is able to collaborate with other personnel. The fourth competency is knowledgeable of the measurement and evaluation. The fifth competency is to understand federal and state laws. The sixth competency is knowledgeable of the unique characteristics of all learners. The seventh competency is the ability to write in behavioral terms for objectives. The eighth competency is knowledgeable of developmental characteristics. The ninth competency is knowledgeable of normal and abnormal motor behaviors. The tenth competency is the ability to analyze and adapt the physical education curriculums. The eleventh competency is to understand the history and the philosophy of physical education. The twelfth competency is to understand curriculum theory and development. The thirteenth competency is the ability to utilize instructional designs and plans. The fourteenth competency is the ability to create and implement physical activities. The fifteenth competency is the ability to utilize technology applications. The sixteenth competency is to understand the value of program evaluation. The seventeenth competency is to understand professional standards. The eighteenth competency is knowledgeable of the focused instruction and individualized interventions. The nineteenth competency is able to complete a research project independently. The twentieth competency is to teach children with disabilities in APE independently. The 4-point Likert-type scale ranges from 1 for incompetent to 4 for highly competent. This scale is used for assessing if one completing all course works is eligible for receiving an endorsement for teaching children with disabilities in APE, which is completed based on the grades earned on three courses targeted for each standard-based competency. A mean grade received in three courses primarily addressing a standard-based competency will be marked on a competency level in the above scale. The level 4 is marked for a mean grade of A one receives over three courses, the level 3 for a mean grade of B over three courses, and so on. One should receive a mean score of 3 (competent level) or higher (highly competent) across 19 standard-based competencies after completing all courses specified for receiving an endorsement for teaching children with disabilities in APE. The validity, reliability, and objectivity of this standard-based competency evaluation scale are to be documented.Keywords: evaluation scale, teacher preparation, adapted physical education teachers, and children with disabilities
Procedia PDF Downloads 1161643 Fusing Mentorship, Leadership and Empowerment Among Young Women In STEM
Authors: Anne Bubriski
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Despite improvements in gender inequalities, women and girls continue to face glass ceilings, underrepresentation, and harmful stereotypes that can limit their aspirations and opportunities in STEM. While girls are taking similar high school math and science classes, boys are more likely to take physics and six times more likely to take an engineering course. The gap becomes even larger for minority or low-income girls. This gender gap is not due to biology; rather, it is due to cultural, social, and institutional forces. As girls get older, these forces often ‘teach’ them ‘STEM is more for boys’. The STEM gender gap widens in college, with only 20% of engineering degrees being awarded to women, and by the time women enter the workforce, they only occupy about 13% of engineering jobs. At the University of Central Florida, the Women’s and Gender Studies Program has developed a unique mentoring program to address these issues, Science Leadership and Mentoring (SLAM). What is unique about the approach of SLAM is that we look to address this problem through leadership and STEM. We look to help girls make connections between leadership and STEM—that young women can be leaders as scientists and that scientists are leaders making a change. This is particularly needed and relevant to our community because while there are mentoring programs to our knowledge, SLAM is one of the only, if not only, mentoring programs pairing college women and 7th-grade girls that includes a focus both on STEM and leadership in the United States. SLAM is a curriculum-based mentoring program pairing one 7th-grade girl with one UCF undergraduate STEM major. SLAM empowers young women to be assertive, brave, confident, independent, inquisitive and proud leaders in STEM. SLAM seeks to promote young women’s inspiration and excitement into STEM fields and careers while also building leadership abilities such as problem-solving, teamwork and cooperation, cultural identity and ethnic pride, advocacy for positive change, and goals for the future. SLAM serves about fifteen 7th-grade girls for the academic year and about 20 UCF students. SLAM holds weekly mentoring meetings lasting about 90 minutes, covering topics on leadership, STEM majors and careers, and STEM leadership. This past year, SLAM received a Community Action Grant from the American Association of University Women (AAUW) to run a sub-program, SLAM-Space. SLAM-Space focused on exposing SLAM participants to aerospace engineering and other space-related STEM fields, such as physics and astronomy, through guest speakers, workshops and field trips, including the Kenndy Space Center. The proposed paper presentation will present an overview of SLAM-Space and the data findings from pre and post-surveys, in-depth interviews and focus groups from the SLAM participants' experiences in the program.Keywords: gender, leadership, STEM, empowerment
Procedia PDF Downloads 391642 Intracranial Hypertension without CVST in Apla Syndrome: An Unique Association
Authors: Camelia Porey, Binaya Kumar Jaiswal
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BACKGROUND: Antiphospholipid antibody (APLA) syndrome is an autoimmune disorder predisposing to thrombotic complications affecting CNS either by arterial vasooclusion or venous thrombosis. Cerebral venous sinus thrombosis (CVST) secondarily causes raised intracranial pressure (ICP). However, intracranial hypertension without evidence of CVST is a rare entity. Here we present two cases of elevated ICP with absence of identifiable CVST. CASE SUMMARY: Case 1, 28-year female had a 2 months history of holocranial headache followed by bilateral painless vision loss reaching lack of light perception over 20 days. CSF opening pressure was elevated. Fundoscopy showed bilateral grade 4 papilledema. MRI revealed a partially empty sella with bilateral optic nerve tortuosity. Idiopathic intracranial hypertension (IIH) was diagnosed. With acetazolamide, there was complete resolution of the clinical and radiological abnormalities. 5 months later she presented with acute onset right-sided hemiparesis. MRI was suggestive of acute left MCA infarct.MR venogram was normal. APLA came positive with high titres of Anticardiolipin and Beta 2 glycoprotein both IgG and IgM. Case 2, 23-year female, presented with headache and diplopia of 2 months duration. CSF pressure was elevated and Grade 3 papilledema was seen. MRI showed bilateral optic nerve hyperintensities with nerve head protrusion with normal MRV. APLA profile showed elevated beta 2 glycoprotein IgG and IgA. CONCLUSION: This is an important non thrombotic complication of APLA syndrome and requires further large-scale study for insight into the pathogenesis and early recognition to avoid future complications.Keywords: APLA syndrome, idiopathic intracranial hypertension, MR venogram, papilledema
Procedia PDF Downloads 1761641 Antibacterial and Antioxidant Capacity of Fabric Treated with Purple-Fleshed Sweet Potato Extract
Authors: Kyung Hwa Hong, Eunmi Koh
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Wool and cotton fabrics are pretreated by a tannic acid aqueous solution to increase their dyeability and then dyed by Purple-Fleshed Sweet Potato (PSP) extract. The dyed fabrics are then investigated by various analysis techniques. The results revealed that wool and cotton fabrics can be dyed bluish red through the pretreatment and dyeing process. Both wool and cotton fabrics only pretreated with tannic acid display decreased L* value but no significant changes in a* and b* values as the concentration of tannic acid increases. And, as expected, the pretreated fabrics are even darker and show a richer purple color after the dyeing process with the PSP extract. With regard to the colorfastness of wool and cotton fabrics dyed by PSP extract in cleaning circumstances, such as dry-cleaning (for wool) and washing (for cotton), the wool and cotton fabrics had a 4.0 and 4.0 grade of colorfastness to dry-cleaning and washing, respectively. However, they both exhibited significantly inferior colorfastness to light (grade of 1.5). Thus, it was found that there is still a need for improvement with regard to color fastness, particularly against light. On the other hand, the wool and cotton fabrics also showed antibacterial and antioxidant characteristics. In addition, both the wool and cotton fabrics showed potential antibacterial ability (>99%) against Staphylococcus aureus; however, they showed somewhat insufficient antibacterial ability (60.8% for wool and 94.8% for cotton) against Klebsiella pneumoniae. Also, their antioxidant abilities increased up to ca. 90% with an increase in the tannic acid concentration (up to 0.5%). However, after the dyeing process, the antibacterial and antioxidant ability tended to decrease. This is assumed to have occurred because functional moieties such as phenolic acids were detached from the pretreated fabrics into the hot water (the dyeing solution) during the dyeing process. Therefore, further study would be necessary to derive the optimum treatment and dyeing conditions so as to maximize the coloring effect and functionalities of the fabrics.Keywords: antibacterial activity, antioxidant activity, purple-fleshed sweet potato, fabrics
Procedia PDF Downloads 2921640 Design, Development, and Performance Evaluation of Hybrid Cross Axis Wind Turbine
Authors: Gwani M., Umar M. Kangiwa, Bello A. Umar, Gado A. Abubakar
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The increasing demand for sustainable energy solutions has driven significant interest in the development of innovative designs of wind turbines. The horizontal axis wind turbine (HAWT) and the vertical axis wind turbine (VAWT) are the dominant type of wind turbine used for power generation. However, these turbines have their respective merits and demerits, which affect their performance. This study introduces a Hybrid Cross Axis Wind Turbine (HCAWT), which integrates the blades of both horizontal axis wind turbines (HAWTs) and vertical axis wind turbines (VAWTs) in a cross-axis configuration with a Savonius rotor to form a hybrid system. The HCAWT combines the self-starting capabilities of Savonius rotors with the high-efficiency characteristics of Darrieus rotors and HAWT, aiming to optimize performance across a range of wind conditions. The performance of the HCAWT was tested and evaluated against a cross-axis wind turbine (CAWT) and a conventional VAWT under similar experimental conditions. The study’s results indicate that the HCAWT outperformed both the CAWT and the conventional VAWT. The power coefficient (Cp) of the HCAWT increases by 83% and 132% compared to that of the CAWT and conventional VAWT, respectively. The findings show that the HCAWT offers better start-up performance and maintains higher efficiency at lower wind speeds compared to CAWT and conventional VAWT. The findings suggest that the HCAWT offers significant improvements in energy capture, particularly in turbulent wind conditions, and greater adaptability to changing wind conditions, making it a viable option for both urban and rural energy applications.Keywords: renewable energy, hybrid, cross axis wind turbine, energy efficiency
Procedia PDF Downloads 101639 Effect of Treated Grey Water on Bacterial Concrete
Authors: Deepa T., Inchara S. R., Venkatesh S. V., Seema Tharannum
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Concrete is the most widely used structural material. It is usually made using locally available materials. However, concrete has low tensile strength and may crack in the early days with exothermic hydration, for which water is essential. To address the increased construction water demand, treated greywater may be used. Bacillus subtilis bacteria that form endospores is the biological agent considered in this study for biomineralization or Microbially Induced Calcite Precipitation (MICP) technique to heal cracks. Treated grey water which is obtained from STP of PES University, opted in place of Potable water, which had qualities within the standard range as per codal provisions. In this work, M30 grade conventional concrete is designed using OPC 53-grade cement, manufactured sand, natural coarse aggregates, and potable water. Conventional concrete (CC), bacterial concrete with potable water (BS), and treated grey water concrete (TGWBS) are the three different concrete specimens cast. Experimental studies such as the strength test and the surface hardness test are performed on conventional and bacterial concrete samples after 7, 28, and 56 days of curing. Concrete cubes are subjected to a temperature of 50° C to investigate the effect of higher temperature. Cracked cube specimens are observed for self-healing -as well as microstructure analysis with Scanning Electron Microscope (SEM), Energy Dispersive X-Ray Analysis (EDAX), and X-Ray Diffraction Analysis (XRD). Noticeable calcium salt deposition is observed on the surface of the BS and TGWBS cracked specimen. Surface hardness and the EDAX test gave promising results on the advantage of using spore-forming bacteria in concrete. This is followed by the strength gained in compression and flexure. Results also indicate that treated grey water can be a substitute for potable water in concrete.Keywords: Bacillus subtilis concrete, microstructure, temperature, treated greywater
Procedia PDF Downloads 991638 The Relationships among Learning Emotion, Major Satisfaction, Learning Flow, and Academic Achievement in Medical School Students
Authors: S. J. Yune, S. Y. Lee, S. J. Im, B. S. Kam, S. Y. Baek
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This study explored whether academic emotion, major satisfaction, and learning flow are associated with academic achievement in medical school. We know that emotion and affective factors are important factors in students' learning and performance. Emotion has taken the stage in much of contemporary educational psychology literature, no longer relegated to secondary status behind traditionally studied cognitive constructs. Medical school students (n=164) completed academic emotion, major satisfaction, and learning flow online survey. Academic performance was operationalized as students' average grade on two semester exams. For data analysis, correlation analysis, multiple regression analysis, hierarchical multiple regression analyses and ANOVA were conducted. The results largely confirmed the hypothesized relations among academic emotion, major satisfaction, learning flow and academic achievement. Positive academic emotion had a correlation with academic achievement (β=.191). Positive emotion had 8.5% explanatory power for academic achievement. Especially, sense of accomplishment had a significant impact on learning performance (β=.265). On the other hand, negative emotion, major satisfaction, and learning flow did not affect academic performance. Also, there were differences in sense of great (F=5.446, p=.001) and interest (F=2.78, p=.043) among positive emotion, boredom (F=3.55, p=.016), anger (F=4.346, p=.006), and petulance (F=3.779, p=.012) among negative emotion by grade. This study suggested that medical students' positive emotion was an important contributor to their academic achievement. At the same time, it is important to consider that some negative emotions can act to increase one’s motivation. Of particular importance is the notion that instructors can and should create learning environment that foster positive emotion for students. In doing so, instructors improve their chances of positively impacting students’ achievement emotions, as well as their subsequent motivation, learning, and performance. This result had an implication for medical educators striving to understand the personal emotional factors that influence learning and performance in medical training.Keywords: academic achievement, learning emotion, learning flow, major satisfaction
Procedia PDF Downloads 2721637 Seasonal Variability of M₂ Internal Tides Energetics in the Western Bay of Bengal
Authors: A. D. Rao, Sachiko Mohanty
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The Internal Waves (IWs) are generated by the flow of barotropic tide over the rapidly varying and steep topographic features like continental shelf slope, subsurface ridges, and the seamounts, etc. The IWs of the tidal frequency are generally known as internal tides. These waves have a significant influence on the vertical density and hence causes mixing in the region. Such waves are also important in submarine acoustics, underwater navigation, offshore structures, ocean mixing and biogeochemical processes, etc. over the shelf-slope region. The seasonal variability of internal tides in the Bay of Bengal with special emphasis on its energetics is examined by using three-dimensional MITgcm model. The numerical simulations are performed for different periods covering August-September, 2013; November-December, 2013 and March-April, 2014 representing monsoon, post-monsoon and pre-monsoon seasons respectively during which high temporal resolution in-situ data sets are available. The model is initially validated through the spectral estimates of density and the baroclinic velocities. From the estimates, it is inferred that the internal tides associated with semi-diurnal frequency are more dominant in both observations and model simulations for November-December and March-April. However, in August, the estimate is found to be maximum near-inertial frequency at all the available depths. The observed vertical structure of the baroclinic velocities and its magnitude are found to be well captured by the model. EOF analysis is performed to decompose the zonal and meridional baroclinic tidal currents into different vertical modes. The analysis suggests that about 70-80% of the total variance comes from Mode-1 semi-diurnal internal tide in both observations as well as in the model simulations. The first three modes are sufficient to describe most of the variability for semidiurnal internal tides, as they represent 90-95% of the total variance for all the seasons. The phase speed, group speed, and wavelength are found to be maximum for post-monsoon season compared to other two seasons. The model simulation suggests that the internal tide is generated all along the shelf-slope regions and propagate away from the generation sites in all the months. The model simulated energy dissipation rate infers that its maximum occurs at the generation sites and hence the local mixing due to internal tide is maximum at these sites. The spatial distribution of available potential energy is found to be maximum in November (20kg/m²) in northern BoB and minimum in August (14kg/m²). The detailed energy budget calculation are made for all the seasons and results are analysed.Keywords: available potential energy, baroclinic energy flux, internal tides, Bay of Bengal
Procedia PDF Downloads 1701636 Prediction of Pile-Raft Responses Induced by Adjacent Braced Excavation in Layered Soil
Authors: Linlong Mu, Maosong Huang
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Considering excavations in urban areas, the soil deformation induced by the excavations usually causes damage to the surrounding structures. Displacement control becomes a critical indicator of foundation design in order to protect the surrounding structures. Evaluation, the damage potential of the surrounding structures induced by the excavations, usually depends on the finite element method (FEM) because of the complexity of the excavation and the variety of the surrounding structures. Besides, evaluation the influence of the excavation on surrounding structures is a three-dimensional problem. And it is now well recognized that small strain behaviour of the soil influences the responses of the excavation significantly. Three-dimensional FEM considering small strain behaviour of the soil is a very complex method, which is hard for engineers to use. Thus, it is important to obtain a simplified method for engineers to predict the influence of the excavations on the surrounding structures. Based on large-scale finite element calculation with small-strain based soil model coupling with inverse analysis, an empirical method is proposed to calculate the three-dimensional soil movement induced by braced excavation. The empirical method is able to capture the small-strain behaviour of the soil. And it is suitable to be used in layered soil. Then the free-field soil movement is applied to the pile to calculate the responses of the pile in both vertical and horizontal directions. The asymmetric solutions for problems in layered elastic half-space are employed to solve the interactions between soil points. Both vertical and horizontal pile responses are solved through finite difference method based on elastic theory. Interactions among the nodes along a single pile, pile-pile interactions, pile-soil-pile interaction action and soil-soil interactions are counted to improve the calculation accuracy of the method. For passive piles, the shadow effects are also calculated in the method. Finally, the restrictions of the raft on the piles and the soils are summarized as: (1) the summations of the internal forces between the elements of the raft and the elements of the foundation, including piles and soil surface elements, is equal to 0; (2) the deformations of pile heads or of the soil surface elements are the same as the deformations of the corresponding elements of the raft. Validations are carried out by comparing the results from the proposed method with the results from the model tests, FEM and other existing literatures. From the comparisons, it can be seen that the results from the proposed method fit with the results from other methods very well. The method proposed herein is suitable to predict the responses of the pile-raft foundation induced by braced excavation in layered soil in both vertical and horizontal directions when the deformation is small. However, more data is needed to verify the method before it can be used in practice.Keywords: excavation, pile-raft foundation, passive piles, deformation control, soil movement
Procedia PDF Downloads 2311635 Modelling of a Biomechanical Vertebral System for Seat Ejection in Aircrafts Using Lumped Mass Approach
Authors: R. Unnikrishnan, K. Shankar
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In the case of high-speed fighter aircrafts, seat ejection is designed mainly for the safety of the pilot in case of an emergency. Strong windblast due to the high velocity of flight is one main difficulty in clearing the tail of the aircraft. Excessive G-forces generated, immobilizes the pilot from escape. In most of the cases, seats are ejected out of the aircrafts by explosives or by rocket motors attached to the bottom of the seat. Ejection forces are primarily in the vertical direction with the objective of attaining the maximum possible velocity in a specified period of time. The safe ejection parameters are studied to estimate the critical time of ejection for various geometries and velocities of flight. An equivalent analytical 2-dimensional biomechanical model of the human spine has been modelled consisting of vertebrae and intervertebral discs with a lumped mass approach. The 24 vertebrae, which consists of the cervical, thoracic and lumbar regions, in addition to the head mass and the pelvis has been designed as 26 rigid structures and the intervertebral discs are assumed as 25 flexible joint structures. The rigid structures are modelled as mass elements and the flexible joints as spring and damper elements. Here, the motions are restricted only in the mid-sagittal plane to form a 26 degree of freedom system. The equations of motions are derived for translational movement of the spinal column. An ejection force with a linearly increasing acceleration profile is applied as vertical base excitation on to the pelvis. The dynamic vibrational response of each vertebra in time-domain is estimated.Keywords: biomechanical model, lumped mass, seat ejection, vibrational response
Procedia PDF Downloads 2311634 The Impact of Ultrasonicator on the Vertical and Horizontal Mixing Profile of Petrol-Bioethanol
Authors: D. Nkazi, S. E. Iyuke, J. Mulopo
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Increasing global energy demand as well as air quality concerns have in recent years led to the search for alternative clean fuels to replace fossil fuels. One such alternative is the blending of petrol with ethanol, which has numerous advantages such ethanol’s ability to act as oxygenate thus reducing the carbon monoxide emissions from the exhaust of internal combustion engines of vehicles. However, the hygroscopic nature of ethanol is a major concern in obtaining a perfectly homogenized petrol-ethanol fuel. This problem has led to the study of ways of homogenizing the petrol-ethanol mixtures. During the blending process, volumes fraction of ethanol and petrol were studied with respect to the depth within the storage container to confirm homogenization of the blend and time of storage. The results reveal that the density of the mixture was constant. The binodal curve of the ternary diagram shows an increase of homogeneous region, indicating an improved of interaction between water and petrol. The concentration distribution in the reactor showed proof of cavitation formation since in both directions, the variation of concentration with both time and distance was found to be oscillatory. On comparing the profiles in both directions, the concentration gradient, diffusion flux, and energy and diffusion rates were found to be higher in the vertical direction compared to the horizontal direction. It was therefore concluded that ultrasonication creates cavitation in the mixture which enhances mass transfer and mixing of ethanol and petrol. The horizontal direction was found to be the diffusion rate limiting step which proposed that the blender should have a larger height to diameter ratio. It is, however, recommended that further studies be done on the rate-limiting step so as to have actual dimensions of the reactor.Keywords: ultrasonication, petrol, ethanol, concentration
Procedia PDF Downloads 3651633 Hydrometallurgical Processing of a Nigerian Chalcopyrite Ore
Authors: Alafara A. Baba, Kuranga I. Ayinla, Folahan A. Adekola, Rafiu B. Bale
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Due to increasing demands and diverse applications of copper oxide as pigment in ceramics, cuprammonium hydroxide solution for rayon, p-type semi-conductor, dry cell batteries production and as safety disposal of hazardous materials, a study on the hydrometallurgical operations involving leaching, solvent extraction and precipitation for the recovery of copper for producing high grade copper oxide from a Nigerian chalcopyrite ore in chloride media has been examined. At a particular set of experimental parameter with respect to acid concentration, reaction temperature and particle size, the leaching investigation showed that the ore dissolution increases with increasing acid concentration, temperature and decreasing particle diameter at a moderate stirring. The kinetics data has been analyzed and was found to follow diffusion control mechanism. At optimal conditions, the extent of ore dissolution reached 94.3%. The recovery of the total copper from the hydrochloric acid-leached chalcopyrite ore was undertaken by solvent extraction and precipitation techniques, prior to the beneficiation of the purified solution as copper oxide. The purification of the leach liquor was firstly done by precipitation of total iron and manganese using Ca(OH)2 and H2O2 as oxidizer at pH 3.5 and 4.25, respectively. An extraction efficiency of 97.3% total copper was obtained by 0.2 mol/L Dithizone in kerosene at 25±2ºC within 40 minutes, from which ≈98% Cu from loaded organic phase was successfully stripped by 0.1 mol/L HCl solution. The beneficiation of the recovered pure copper solution was carried out by crystallization through alkali addition followed by calcination at 600ºC to obtain high grade copper oxide (Tenorite, CuO: 05-0661). Finally, a simple hydrometallurgical scheme for the operational extraction procedure amenable for industrial utilization and economic sustainability was provided.Keywords: chalcopyrite ore, Nigeria, copper, copper oxide, solvent extraction
Procedia PDF Downloads 3931632 Effect of High-Intensity Core Muscle Exercises Training on Sport Performance in Dancers
Authors: Che Hsiu Chen, Su Yun Chen, Hon Wen Cheng
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Traditional core stability, core endurance, and balance exercises on a stable surface with isometric muscle actions, low loads, and multiple repetitions, which may not improvements the swimming and running economy performance. However, the effects of high intensity core muscle exercise training on jump height, sprint, and aerobic fitness remain unclear. The purpose of this study was to examine whether high intensity core muscle exercises training could improve sport performances in dancers. Thirty healthy university dancer students (28 women and 2 men; age 20.0 years, height 159.4 cm, body mass 52.7 kg) were voluntarily participated in this study, and each participant underwent five suspension exercises (e.g., hip abduction in plank alternative, hamstring curl, 45-degree row, lunge and oblique crunch). Each type of exercise was performed for 30-second, with 30-second of rest between exercises, two times per week for eight weeks and each exercise session was increased by 10-second every week. We measured agility, explosive force, anaerobic and cardiovascular fitness in dancer performance before and after eight weeks of training. The results showed that the 8-week high intensity core muscle training would significantly increase T-test agility (7.78%), explosive force of acceleration (3.35%), vertical jump height (8.10%), jump power (6.95%), lower extremity anaerobic ability (7.10%) and oxygen uptake efficiency slope (4.15%). Therefore, it can be concluded that eight weeks of high intensity core muscle exercises training can improve not only agility, sprint ability, vertical jump ability, anaerobic and but also cardiovascular fitness measures as well.Keywords: balance, jump height, sprint, maximal oxygen uptake
Procedia PDF Downloads 4071631 Act Local, Think Global: Superior Institute of Engineering of Porto Campaign for a Sustainable Campus
Authors: R. F. Mesquita Brandão
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Act Local, Think Global is the name of a campaign implemented at Superior Institute of Engineering of Porto (ISEP), one of schools of Polytechnic of Porto, with the main objective of increase the sustainability of the campus. ISEP has a campus with 52.000 m2 and more than 7.000 students. The campaign started in 2019 and the results are very clear. In 2019 only 16% of the waste created in the campus was correctly separate for recycling and now almost 50% of waste goes to the correct waste container. Actions to reduce the energy consumption were implemented with significantly results. One of the major problems in the campus are the water leaks. To solve this problem was implemented a methodology for water monitoring during the night, a period of time where consumptions are normally low. If water consumption in the period is higher than a determinate value it may mean a water leak and an alarm is created to the maintenance teams. In terms of energy savings, some measurements were implemented to create savings in energy consumption and in equivalent CO₂ produced. In order to reduce the use of plastics in the campus, was implemented the prohibition of selling 33 cl plastic water bottles and in collaboration with the students association all meals served in the restaurants changed the water plastic bottle for a glass that can be refilled with water in the water dispensers. This measures created a reduction of use of more than 75.000 plastic bottles per year. In parallel was implemented the ISEP water glass bottle to be used in all scientific meetings and events. Has a way of involving all community in sustainability issues was developed and implemented a vertical garden in aquaponic system. In 2019, the first vertical garden without soil was installed inside a large campus building. The system occupies the entire exterior façade (3 floors) of the entrance to ISEP's G building. On each of these floors there is a planter with 42 positions available for plants. Lettuces, strawberries, peppers are examples of some vegetable produced that can be collected by the entire community. Associated to the vertical garden was developed a monitoring system were some parameters of the system are monitored. This project is under development because it will work in a stand-alone energy feeding, with the use of photovoltaic panels for production of energy necessities. All the system was, and still is, developed by students and teachers and is used in class projects of some ISEP courses. These and others measures implemented in the campus, will be more developed in the full paper, as well as all the results obtained, allowed ISEP to be the first Portuguese high school to obtain the certification “Coração Verde” (Green Heart), awarded by LIPOR, a Portuguese company with the mission of transform waste into new resources through the implementation of innovative and circular practices, generating and sharing value.Keywords: aquaponics, energy efficiency, recycling, sustainability, waste separation
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