Search results for: arterial wall movement

Authors: Matjaz Prek

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Impact of three different combinations of cooling and ventilation systems on the indoor environmental quality (IEQ) has been studied. Comparison of chilled ceiling cooling in combination with displacement ventilation, cooling with fan coil unit and cooling with flat wall displacement outlets was performed. All three combinations were evaluated from the standpoint of whole-body and local thermal comfort criteria as well as from the standpoint of ventilation effectiveness. The comparison was made on the basis of numerical simulation with DesignBuilder and Fluent. Numerical simulations were carried out in two steps. Firstly the DesignBuilder software environment was used to model the buildings thermal performance and evaluation of the interaction between the environment and the building. Heat gains of the building and of the individual space, as well as the heat loss on the boundary surfaces in the room, were calculated. In the second step Fluent software environment was used to simulate the response of the indoor environment, evaluating the interaction between building and human, using the simulation results obtained in the first step. Among the systems presented, the ceiling cooling system in combination with displacement ventilation was found to be the most suitable as it offers a high level of thermal comfort with adequate ventilation efficiency. Fan coil cooling has proved inadequate from the standpoint of thermal comfort whereas flat wall displacement outlets were inadequate from the standpoint of ventilation effectiveness. The study showed the need in evaluating indoor environment not solely from the energy use point of view, but from the point of view of indoor environmental quality as well.

Keywords: cooling, ventilation, thermal comfort, ventilation effectiveness, indoor environmental quality, IEQ, computational fluid dynamics

Procedia PDF Downloads 176

Authors: Tempe S. F. Adams, Michael J. Chase, Tracey L. Rogers, Keith E. A. Leggett

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Transfrontier wildlife corridors can be successful conservation tools, connecting protected areas and reducing the impact of habitat fragmentation on mobile species. Urban wildlife corridors have been proposed as a potential mitigation tool to facilitate the passage of elephants through towns without causing conflict with urban communities. However, because such corridors are typically narrow and close to human development, wildlife (particularly large mammals) may be less likely to use them. We used remote-sensor camera traps and global positioning system collars to identify the movement patterns of African elephants Loxondonta africana through narrow, urban corridors in Botswana. The corridors were in three types of human-dominated land-use designations with varying levels of human activity: agricultural, industrial and open space recreational land. We found that elephants used the corridors within all three land-use designations and we identified, using a model selection approach, that season, time of day and rainfall were important factors in determining the presence of elephants in the corridors. Elephants moved more slowly through the narrow corridors compared with their movement patterns through broader, wide-ranging corridors. Our results indicate that urban wildlife corridors are useful for facilitating elephants to pass through urban areas.

Keywords: camera traps, conservation, human-elephant coexistence, land management, urban wildlife corridors

Procedia PDF Downloads 286

Authors: Pratibha Biswal, Suyash Morchhale, Anshuman Singh Yadav, Shubham Sanjay Chobe

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Energy demands are increasing whereas energy sources, especially non-renewable sources are limited. Due to the intermittent nature of renewable energy sources, it has become the need of the hour to find new ways to store energy. Out of various energy storage methods, latent heat thermal storage devices are becoming popular due to their high energy density per unit mass and volume at nearly constant temperature. This work presents a computational fluid dynamics (CFD) model using ANSYS FLUENT 19.0 for energy storage characteristics of a phase change material (PCM) filled in a vertical triplex tube thermal energy storage system. A vertical triplex tube heat exchanger, just like its name consists of three concentric tubes (pipe sections) for parting the device into three fluid domains. The PCM is filled in the middle domain with heat transfer fluids flowing in the outer and innermost domains. To enhance the heat transfer inside the PCM, eight fins have been incorporated between the internal and external tubes. These fins run radially outwards from the outer-wall of innermost tube to the inner-wall of the middle tube dividing the middle domain (between innermost and middle tube) into eight sections. These eight sections are then filled with a PCM. The validation is carried with earlier work and a grid independence test is also presented. Further studies on freezing and melting process were carried out. The results are presented in terms of pictorial representation of isotherms and liquid fraction

Keywords: heat exchanger, thermal energy storage, phase change material, CFD, latent heat

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Authors: Elisabeth Maidl

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The interdependence of climate change and natural hazard goes along with large uncertainties regarding future risks. Regional stakeholders, experts in natural hazards management and scientists have specific knowledge, resp. mental models on such risks. This diversity of views makes it difficult to find common and broadly accepted prevention measures. If the specific knowledge of these types of actors is shared in an interactive knowledge production process, this enables a broader and common understanding of complex risks and allows to agree on long-term solution strategies. Previous studies on mental models confirm that actors with specific vulnerabilities perceive different aspects of a topic and accordingly prefer different measures. In bringing these perspectives together, there is the potential to reduce uncertainty and to close blind spots in solution finding. However, studies that examine the mental models of regional actors on future concrete mass movement risks are lacking so far. The project tests and evaluates the feasibility of knowledge co-creation for the anticipatory prevention of climate change-induced mass movement risks in the Alps. As a key element, mental models of the three included groups of actors are compared. Being integrated into the research program Climate Change Impacts on Alpine Mass Movements (CCAMM2), this project is carried out in two Swiss mountain regions. The project is structured in four phases: 1) the preparatory phase, in which the participants are identified, 2) the baseline phase, in which qualitative interviews and a quantitative pre-survey are conducted with actors 3) the knowledge-co-creation phase, in which actors have a moderated exchange meeting, and a participatory modelling workshop on specific risks in the region, and 4) finally a public information event. Results show that participants' mental models are based on the place of origin, profession, believes, values, which results in narratives on climate change and hazard risks. Further, the more intensively participants interact with each other, the more likely is that they change their views. This provides empirical evidence on how changes in opinions and mindsets can be induced and fostered.

Keywords: climate change, knowledge-co-creation, participatory process, natural hazard risks

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Authors: Naeim Akbari Shahkhosravi, Reza Kakavand, Helen M. S. Davies, Amin Komeili

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Equine locomotion and performance are significantly affected by hoof health. One of the most critical diseases of the hoof is laminitis, which can lead to horse lameness in a severe condition. This disease exhibits the mechanical properties degradation of the laminar junction tissue within the hoof. Therefore, it is essential to investigate the biomechanics of the hoof, focusing specifically on excessive and cumulatively accumulated stresses within the laminar junction tissue. For this aim, the current study generated a novel equine hoof Finite Element (FE) model under dynamic physiological loading conditions and employing a hyperelastic material model. Associated tissues of the equine hoof were segmented from computed tomography scans of an equine forelimb, including the navicular bone, third phalanx, sole, frog, laminar junction, digital cushion, and medial- dorsal- lateral wall areas. The inner tissues were connected based on the hoof anatomy, and the hoof was under a dynamic loading over cyclic strides at the trot. The strain distribution on the hoof wall of the model was compared with the published in vivo strain measurements to validate the model. Then the validated model was used to study the development of laminitis. The ultimate stress tolerated by the laminar junction before rupture was considered as a stress threshold. The tissue damage was simulated through iterative reduction of the tissue’s mechanical properties in the presence of excessive maximum principal stresses. The findings of this investigation revealed how damage initiates from the medial and lateral sides of the tissue and propagates through the hoof dorsal area.

Keywords: horse hoof, laminitis, finite element model, continuous damage

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Authors: Heather E. Ewart, Keith Jensen, Rebecca N. Cliffe

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Fragmentation and changes in the structural composition of tropical forests – as a result of intensifying anthropogenic disturbance – are increasing pressures on local biodiversity. Species with low dispersal abilities have some of the highest extinction risks in response to environmental change, as even small-scale environmental variation can substantially impact their space use and energetic balance. Understanding the implications of forest disturbance is therefore essential, ultimately allowing for more effective and targeted conservation initiatives. Here, the impact of different levels of forest disturbance on the space use, energetics, movement and behavior of 18 brown-throated sloths (Bradypus variegatus) were assessed in the South Caribbean of Costa Rica. A multi-scale framework was used to measure forest disturbance, including large-scale (landscape-level classifications) and fine-scale (within and surrounding individual home ranges) forest composition. Three landscape-level classifications were identified: primary forests (undisturbed), secondary forests (some disturbance, regenerating) and urban forests (high levels of disturbance and fragmentation). Finer-scale forest composition was determined using measurements of habitat structure and quality within and surrounding individual home ranges for each sloth (home range estimates were calculated using autocorrelated kernel density estimation [AKDE]). Measurements of forest quality included tree connectivity, density, diameter and height, species richness, and percentage of canopy cover. To determine space use, energetics, movement and behavior, six sloths in urban forests, seven sloths in secondary forests and five sloths in primary forests were tracked using a combination of Very High Frequency (VHF) radio transmitters and Global Positioning System (GPS) technology over an average period of 120 days. All sloths were also fitted with micro data-loggers (containing tri-axial accelerometers and pressure loggers) for an average of 30 days to allow for behavior-specific movement analyses (data analysis ongoing for data-loggers and primary forest sloths). Data-loggers included determination of activity budgets, circadian rhythms of activity and energy expenditure (using the vector of the dynamic body acceleration [VeDBA] as a proxy). Analyses to date indicate that home range size significantly increased with the level of forest disturbance. Female sloths inhabiting secondary forests averaged 0.67-hectare home ranges, while female sloths inhabiting urban forests averaged 1.93-hectare home ranges (estimates are represented by median values to account for the individual variation in home range size in sloths). Likewise, home range estimates for male sloths were 2.35 hectares in secondary forests and 4.83 in urban forests. Sloths in urban forests also used nearly double (median = 22.5) the number of trees as sloths in the secondary forest (median = 12). These preliminary data indicate that forest disturbance likely heightens the energetic requirements of sloths, a species already critically limited by low dispersal ability and rates of energy acquisition. Energetic and behavioral analyses from the data-loggers will be considered in the context of fine-scale forest composition measurements (i.e., habitat quality and structure) and are expected to reflect the observed home range and movement constraints. The implications of these results are far-reaching, presenting an opportunity to define a critical index of habitat connectivity for low dispersal species such as sloths.

Keywords: biodiversity conservation, forest disturbance, movement ecology, sloths

Procedia PDF Downloads 90

Authors: A. T. Asutosh, J. Woo, M. Kouhirostami, M. Sam, A. Khantawang, C. Cuales, W. Ryor, C. Kibert

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Climate change and global warming vortex have grown to alarming proportions. Therefore, the need for a shift in the conceptualization of energy production is paramount. Energy practices have been created in the current situation. Fossil fuels continue their prominence, at the expense of renewable sources. Despite this abundance, a large percentage of the world population still has no access to electricity but there have been encouraging signs in global movement from nonrenewable to renewable energy but means to reverse climate change have been elusive. Worldwide, organizations have put tremendous effort into innovation. Conferences and exhibitions act as a platform that allows a broad exchange of information regarding trends in the renewable energy field. The Solar Power International (SPI) conference and exhibition is a gathering of concerned activists, and probably the largest convention of its kind. This study investigates current development in the renewable energy field, analyzing means by which industry is being applied to the issue. In reviewing the 2019 SPI conference, it was found innovations in recycling and assessing the environmental impacts of the solar products that need critical attention. There is a huge movement in the electrical storage but there exists a large gap in the development of security systems. This research will focus on solar energy, but impacts will be relevant to the entire renewable energy market.

Keywords: climate change, renewable energy, solar, trends, research, solar power international, SPI

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Authors: Sayed M. Soleimani, Nader H. Ghareeb, Nourhan H. Shaker, Muhammad B. Siddiqui

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Honeycomb sandwich panels have been widely used as protective structural elements against blast loading. The main advantages of these panels include their light weight due to the presence of voids, as well as their energy absorption capability. Terrorist activities have imposed new challenges to structural engineers to design protective measures for vital structures. Since blast loading is not usually considered in the load combinations during the design process of a structure, researchers around the world have been motivated to study the behavior of potential elements capable of resisting sudden loads imposed by the detonation of explosive materials. One of the best candidates for this objective is the honeycomb sandwich panel. Studying the effects of explosive materials on the panels requires costly and time-consuming experiments. Moreover, these type of experiments need permission from defense organizations which can become a hurdle. As a result, modeling and simulation using an appropriate tool can be considered as a good alternative. In this research work, the finite element package ABAQUS® is used to study the behavior of hexagonal and squared honeycomb steel sandwich panels under the explosive effects of different amounts of trinitrotoluene (TNT). The results of finite element modeling of a specific honeycomb configuration are initially validated by comparing them with the experimental results from literature. Afterwards, several configurations including different geometrical properties of the honeycomb wall are investigated and the results are compared with the original model. Finally, the effectiveness of the core shape and wall thickness are discussed, and conclusions are made.

Keywords: Abaqus, blast loading, finite element modeling, steel honeycomb sandwich panel

Procedia PDF Downloads 335

Authors: S. Mishra, J. Monro, H. Edwards, J. Podd

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When a fruit such as kiwifruit is consumed its tissues are released from the physical /anatomical constraints existing in the fruit. During digestion they may expand several-fold to achieve a hydrated solids volume far greater than the original fruit, and occupy the available space in the gut, where they surround and interact with other food components. Within the cell wall dispersion, in vitro digestion of co-consumed carbohydrate, diffusion of digestion products, and mixing responsible for mass transfer of nutrients to the gut wall for absorption, were all retarded. All of the foregoing processes may be involved in the glycaemic response to carbohydrate foods consumed with kiwifruit, such as breakfast cereal. To examine their combined role in reducing the glycaemic response to wheat cereal consumed with kiwifruit we formulated diets containing equal amounts of breakfast cereal, with the addition of either kiwifruit, or sugars of the same composition and quantity as in kiwifruit. Therefore, the only difference between the diets was the presence of non-digestible fruit residues. The diet containing the entire disperse kiwifruit significantly reduced the glycaemic response amplitude and the area under the 0-120 min incremental blood glucose response curve (IAUC), compared with the equicarbohydrate diet containing the added kiwifruit sugars. It also slightly but significantly increased the 120-180 min IAUC by preventing a postprandial overcompensation, indicating improved homeostatic blood glucose control. In a subsequent study in which we used kiwifruit in a carbohydrate exchange format, in which the kiwifruit carbohydrate partially replaced breakfast cereal in equal carbohydrate meals, the blood glucose was further reduced without a loss of satiety, and with a reduction in insulin demand. The results show that kiwifruit may be a valuable component in low glycaemic impact diets.

Keywords: carbohydrate, digestion, glycaemic response, kiwifruit

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Authors: M. Sohrabi Narciss

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Urban spaces of Tehran, the capital of Iran, have witnessed many revolts, movements, and protests during the past few decades. After the Iranian Constitutional Revolution, the 1979 Revolution has had a profound impact on Tehran’s urban space. In 1979, the world watched as Iranians demonstrated en masse against the Pahlavi dynastdy which eventually led to its overthrow. Tehran’s public space is replete with images and artwork that depict the overthrow of the Pahlavi regime and the establishment of an Islamic government in Iran. The public artworks related to the 1979 Islamic Revolution reflect the riots, protests, and strikes that the Iranians underwent during the revolution. Many of these artworks try to revitalize the events that occurred in the 1970s by means of collective memory. Almost 4 decades have passed since the revolution and ever since the public artwork has been affected either directly or indirectly by the Iran-Iraq War, the Green Movement, and the rise and fall of various political forces. The present study is an attempt to investigate Tehran’s urban artwork such as urban sculptures and mural paintings organized and supervised by the government and the graffiti drawn by the critics or the opposition groups. To this end, in addition to the available documents, field research and questionnaires were used to qulaitatively analyze the data. This paper tries to address the following questions: 1) what changes have occurred in Tehran’s urban art? 2) Does the public, revolution-related artwork have an effect on people’s vitality? 3) do Iranians find these artworks appealing or not?

Keywords: public space, Tehran, public art, movement, Islamic revolution

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Authors: Nyussupova Gulnara, Kenespayeva Laura, Kelinbayeva Roza, Aubakirova Gaukhar, Zhumagulov Chingiz, Aidarkhanova Gaukhar

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The article analyzes the development of demographic processes in four regions of the Western region of the Republic of Kazakhstan (Aktobe, Atyrau, West Kazakhstan, and Mangystau) for the period from 2000 to 2022. This study uses theoretical and methodological analysis of scientific literature, methods of comparative, statistical analysis, GIS methods, grouping and systematization, index method and structural analysis. The research identified regional characteristics, development trends, and disproportions in the population of the studied areas within the framework of sustainable demographic development. The population dynamics, the age-sex structure of the population, life expectancy, natural movement of the population, including maternal and infant mortality, are considered as important indicators of the region’s sustainability. The features of migration processes in the Western region of Kazakhstan and the factors that determine them are identified. Conclusions are drawn about the level of sustainable development of the population of the studied region based on demographic processes. The results obtained will provide scientific, methodological and information support in the sectors of economics and science, including the preparation of socio-economic development programs and the development of scientific research using GIS.

Keywords: sustainable development, demographic processes, Western Region, Republic of Kazakhstan, population structure, natural population movement, migration

Procedia PDF Downloads 48

Authors: Mounir Baccar, Amel Gammoudi, Abdelhak Ayadi

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The efficient mixing of highly viscous fluids is required for many industries such as food, polymers or paints production. The homogeneity is a challenging operation for this fluids type since they operate at low Reynolds number to reduce the required power of the used impellers. Particularly, close-clearance impellers, mainly helical ribbons, are chosen for highly viscous fluids agitated in laminar regime which is currently heated through vessel wall. Indeed, they are characterized by high shear strains closer to the vessel wall, which causes a disturbing thermal boundary layer and ensures the homogenization of the bulk volume by axial and radial vortices. The hydrodynamic and thermal behaviors of Newtonian fluids in vessels agitated by helical ribbon impellers, has been mostly studied by many researchers. However, rarely researchers investigated numerically the agitation of yield stress fluid by means of helical ribbon impellers. This paper aims to study the effect of the Double Helical Ribbon (DHR) stirrers on both the hydrodynamic and the thermal behaviors of yield stress fluids treated in a cylindrical vessel by means of numerical simulation approach. For this purpose, continuity, momentum, and thermal equations were solved by means of 3D finite volume technique. The effect of Oldroyd (Od) and Reynolds (Re) numbers on the power (Po) and Nusselt (Nu) numbers for the mentioned stirrer type have been studied. Also, the velocity and thermal fields, the dissipation function and the apparent viscosity have been presented in different (r-z) and (r-θ) planes.

Keywords: Bingham fluid, Hydrodynamic and thermal behavior, helical ribbon, mixing, numerical modelling

Procedia PDF Downloads 289

Authors: A. Sherif, H. Sabry, A. Elzafarany, M. Gadelhak, R. Arafa, M. Aly

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This paper addresses the design of hospital Intensive Care Unit windows for the achievement of visual comfort and energy savings. The aim was to identify the window size and shading system configurations that could fulfill daylighting adequacy, avoid glare and reduce energy consumption. The study focused on addressing the effect of utilizing different shading systems in association with a range of Window-to-Wall Ratios (WWR) in different orientations under the desert clear-sky of Cairo, Egypt. The results of this study demonstrated that solar penetration is a critical concern affecting the design of ICU windows in desert locations, as in Cairo, Egypt. Use of shading systems was found to be essential in providing acceptable daylight performance and energy saving. Careful positioning of the ICU window towards a proper orientation can dramatically improve performance. It was observed that ICU windows facing the north direction enjoyed the widest range of successful window configuration possibilities at different WWRs. ICU windows facing south enjoyed a reasonable number of configuration options as well. By contrast, the ICU windows facing the east orientation had a very limited number of options that provide acceptable performance. These require additional local shading measures at certain times due to glare incidence. Moreover, use of horizontal sun breakers and solar screens to protect the ICU windows proved to be more successful than the other alternatives in a wide range of Window to Wall Ratios. By contrast, the use of light shelves and vertical shading devices seemed questionable.

Keywords: daylighting, desert, energy efficiency, shading

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Authors: Mehmet Yanardag, Ilker Yilmaz

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Children with autism spectrum disorders (ASD) enjoy and success the aquatic-based exercise and play skills in a pool instead of land-based exercise in a gym. Some authors also observed that many children with ASD experience more success in attaining movement skills in aquatic environment. Properties of the water and hydrodynamic principles cause buoyancy of the water and decrease effects of gravity and it leads to allow a child to practice important aquatic skills with limited motor skills. Also, some authors experience that parents liked the effects of the aquatic intervention program on children with ASD such as improving motor performance, movement capacity and learning basic swimming skills. The purpose of this study was to investigate the effects of aquatic exercise training on water orientation and underwater working capacity were measured in the pool. This study included in four male children between 5 and 7 years old with ASD and 6.25±0.5 years old. Aquatic exercise skills were applied by using one of the error less teaching which is called the 'most to least prompt' procedure during 12-week, three times a week and 60 minutes a day. The findings of this study indicated that there were improvements test results both water orientation skill and underwater working capacity of children with ASD after 12-weeks exercise training. It was seen that the aquatic exercise intervention would be affected to improve working capacity and orientation skills with the special education approaches applying children with ASD in multidisciplinary team-works.

Keywords: aquatic, autism, orientation, ASD, children

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Authors: Arindam Chowdhury, Andres Tremante, Mohammadtaghi Moravej, Bodhisatta Hajra, Ioannis Zisis, Peter Irwin

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Extreme wind events, such as hurricanes, have caused significant damage to buildings, resulting in losses worth millions of dollars. The roof of a building is most vulnerable to wind-induced damage due to the high suctions experienced by the roof in extreme wind conditions. Wind turbines fitted to buildings can help generate energy, but to our knowledge, their application to wind load mitigation is not well known. This paper presents results from an experimental study to assess the effect of small wind turbines (developed and patented by the first and second authors) on the wind loads on a low rise building roof. The tests were carried out for an open terrain at the Wall of Wind (WOW) experimental facility at Florida International University (FIU), Miami, Florida, USA, for three cases – bare roof, roof fitted with wind turbines placed closer to the roof edges, and roof with wind turbines placed away from the roof edges. Results clearly indicate that the presence of the wind turbines reduced the mean and peak pressure coefficients (less suction) on the roof when compared to the bare deck case. Furthermore, the peak pressure coefficients were found to be lower (less suction) when the wind turbines were placed closer to the roof, than away from the roof. Flow visualization studies using smoke and gravel clearly showed that the presence of the turbines disrupted the formation of vortices formed by cornering winds, thereby reducing roof suctions and preventing lift off of roof coverings. This study shows that the wind turbines besides generating wind energy, can be used for mitigating wind induced damage to the building roof. Future research must be directed towards understanding the effect of these wind turbines on other roof geometries (e.g. hip/gable) in different terrain conditions.

Keywords: wall of wind, wind loads, wind turbine, building

Procedia PDF Downloads 234

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 265

Authors: Mohamed Mounir Tellache, Hiroyuki Kambara, Yasuharu Koike, Makoto Miyakoshi, Natsue Yoshimura

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This study explores the practicality of using electroencephalographic (EEG) independent components to predict eight-direction finger movements in pseudo-real-time. Six healthy participants with individual-head MRI images performed finger movements in eight directions with two different arm configurations. The analysis was performed in two stages. The first stage consisted of using independent component analysis (ICA) to separate the signals representing brain activity from non-brain activity signals and to obtain the unmixing matrix. The resulting independent components (ICs) were checked, and those reflecting brain-activity were selected. Finally, the time series of the selected ICs were used to predict eight finger-movement directions using Sparse Logistic Regression (SLR). The second stage consisted of using the previously obtained unmixing matrix, the selected ICs, and the model obtained by applying SLR to classify a different EEG dataset. This method was applied to two different settings, namely the single-participant level and the group-level. For the single-participant level, the EEG dataset used in the first stage and the EEG dataset used in the second stage originated from the same participant. For the group-level, the EEG datasets used in the first stage were constructed by temporally concatenating each combination without repetition of the EEG datasets of five participants out of six, whereas the EEG dataset used in the second stage originated from the remaining participants. The average test classification results across datasets (mean ± S.D.) were 38.62 ± 8.36% for the single-participant, which was significantly higher than the chance level (12.50 ± 0.01%), and 27.26 ± 4.39% for the group-level which was also significantly higher than the chance level (12.49% ± 0.01%). The classification accuracy within [–45°, 45°] of the true direction is 70.03 ± 8.14% for single-participant and 62.63 ± 6.07% for group-level which may be promising for some real-life applications. Clustering and contribution analyses further revealed the brain regions involved in finger movement and the temporal aspect of their contribution to the classification. These results showed the possibility of using the ICA-based method in combination with other methods to build a real-time system to control prostheses.

Keywords: brain-computer interface, electroencephalography, finger motion decoding, independent component analysis, pseudo real-time motion decoding

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Authors: Shima Soleimani, Steven Eckels

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One area of special importance for surface-level study of heat exchangers is tubes with internal micro-fins (< 0.5 mm tall). Micro-finned surfaces are a kind of extended solid surface in which energy is exchanged with water that acts as the source or sink of energy. Significant performance gains are possible for either shell, tube, or double pipe heat exchangers if the best surfaces are identified. The parametric studies of micro-finned tubes that have appeared in the literature left some key parameters unexplored. Specifically, they ignored three-dimensional (3D) micro-fin configurations, conduction heat transfer in the fins, and conduction in the solid surface below the micro-fins. Thus, this study aimed at implementing a parametric study of 3D micro-finned tubes that considered micro-fin height and discontinuity features. A 3D conductive and convective heat-transfer simulation through coupled solid and periodic fluid domains is applied in a commercial package, ANSYS Fluent 19.1. The simulation is steady-state with turbulent water flow cooling inner wall of a tube with micro-fins. The simulation utilizes a constant and uniform temperature on the tube outer wall. Performance is mapped for 18 different simulation cases, including a smooth tube using a realizable k-ε turbulence model at a Reynolds number of 48,928. Results compared the performance of 3D tubes with results for the similar two-dimensional (2D) one. Results showed that the micro-fin height has greater impact on performance factor than discontinuity features in 3D micro-fin tubes. A transformed 3D micro-fin tube can enhance heat transfer and pressure drop up to 21% and 56% compared to a 2D one, respectfully.

Keywords: three-dimensional micro-finned tube, heat transfer, friction factor, heat exchanger

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Authors: Alper T. Celebi, Ali Beskok

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Electroosmotic (EO) slip flows in nanochannels are investigated using non-equilibrium molecular dynamics (MD) simulations, and the results are compared with analytical solution of Poisson-Boltzmann and Stokes (PB-S) equations with slip contribution. The ultimate objective of this study is to show that well-known continuum flow model can accurately predict the EO velocity profiles in nanochannels using the slip lengths and apparent viscosities obtained from force-driven flow simulations performed at various liquid-wall interaction strengths. EO flow of aqueous NaCl solution in silicon nanochannels are simulated under realistic electrochemical conditions within the validity region of Poisson-Boltzmann theory. A physical surface charge density is determined for nanochannels based on dissociations of silanol functional groups on channel surfaces at known salt concentration, temperature and local pH. First, we present results of density profiles and ion distributions by equilibrium MD simulations, ensuring that the desired thermodynamic state and ionic conditions are satisfied. Next, force-driven nanochannel flow simulations are performed to predict the apparent viscosity of ionic solution between charged surfaces and slip lengths. Parabolic velocity profiles obtained from force-driven flow simulations are fitted to a second-order polynomial equation, where viscosity and slip lengths are quantified by comparing the coefficients of the fitted equation with continuum flow model. Presence of charged surface increases the viscosity of ionic solution while the velocity-slip at wall decreases. Afterwards, EO flow simulations are carried out under uniform electric field for different liquid-wall interaction strengths. Velocity profiles present finite slips near walls, followed with a conventional viscous flow profile in the electrical double layer that reaches a bulk flow region in the center of the channel. The EO flow enhances with increased slip at the walls, which depends on wall-liquid interaction strength and the surface charge. MD velocity profiles are compared with the predictions from analytical solutions of the slip modified PB-S equation, where the slip length and apparent viscosity values are obtained from force-driven flow simulations in charged silicon nano-channels. Our MD results show good agreements with the analytical solutions at various slip conditions, verifying the validity of PB-S equation in nanochannels as small as 3.5 nm. In addition, the continuum model normalizes slip length with the Debye length instead of the channel height, which implies that enhancement in EO flows is independent of the channel height. Further MD simulations performed at different channel heights also shows that the flow enhancement due to slip is independent of the channel height. This is important because slip enhanced EO flow is observable even in micro-channels experiments by using a hydrophobic channel with large slip and high conductivity solutions with small Debye length. The present study provides an advanced understanding of EO flows in nanochannels. Correct characterization of nanoscale EO slip flow is crucial to discover the extent of well-known continuum models, which is required for various applications spanning from ion separation to drug delivery and bio-fluidic analysis.

Keywords: electroosmotic flow, molecular dynamics, slip length, velocity-slip

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Authors: Hieu Duy Nguyen, Chitsan Lin Jr., Dung Duc Tran

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Nowadays, drought and salinity intrusion becomes a severe problem in the Lower Mekong region due to climate change, especially in coastal provinces. Freshwater resources are decreased due to sea-level rise and the decline in water flow from upstream in the dry season. The combination of the above issues can lead to many effects on the environment and human health in affected areas such as the pathological of digestive or decreased the immune system. Tidal cycle and upstream flows are the two main factors affecting the saline intrusion process and the former salt-wedge in the estuary. Under suitable conditions, salt-wedge can be going further upstream under the water surface and affected groundwater. In order to have a proper plan for the mitigation of the above adverse effects, we need to understand the characteristics of this process. In this study, 3D model is used to investigate the movement of salt-wedge under different conditions of tidal and flow discharge. The salinity in the vertical profile is also measured in the dry season of 2017 and 2018 for model calibrating. The data has proved that there is the presence of salt-wedge in the study area. The obtained results will help strategic planners to use and preserve water resources more effectively and serve as a basis for new research directions on saline intrusion and human health.

Keywords: salt-wedge, salinity intrusion, human health, 3D model

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Authors: Magdy Abouzeid, Nancy Abouzeid, Afaf Salem

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Background: The elite child athletes are one who has superior athletic talent. Monofin (a single surface swim fin) swimming already proved to be the most efficient method of swimming for human being. This is a novel descriptive study examining myocardial function indices in prepubertal monofin children. The aim of the present study was to determine the influence of long-term monofin training (LTMT), 36 weeks, 6 times per week, 90 min per unit on Myocardial function adaptation in elite child monofin athletes. Methods: 14 elite monofin children aged 11.95 years (± 1.09 yr) took part for (LTMT). All subjects underwent two-dimension, M-mode, and Doppler echocardiography before and after training to evaluate cardiac dimensions and function; septal and posterior wall thickness. Statistical methods of SPSS, means ± SD and paired t test, % of improvement were used. Findings: There was significant difference (p<0.01) and % improvement for all echocardiography parameter after (LTMT). Inter ventricular septal thickness in diastole and in systole increased by 27.9 % and 42.75 %. Left ventricular end systolic dimension and diastole increased by 16.81 % and 42.7 % respectively. Posterior wall thickness in systole very highly increased by 283.3 % and in diastole increased by 51.78 %. Left ventricular mass in diastole and in systole increased by 44.8 % and 40.1 % respectively. Stroke volume (SV) and resting heart rate (HR) significant changed (sv) 25 %, (HR) 14.7 %. Interpretation: the unique swim fin tool and create propulsion and overcome resistance. Further researches are needed to determine the effects of monofin training on right ventricular in child athletes.

Keywords: prepubertal, monofin training, heart athlete's, elite child athlete, echocardiography

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Authors: Omar Bouledroua, Djamel Zelmati, Zahreddine Hafsi, Milos B. Djukic

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Transporting hydrogen gas through the existing natural gas pipeline network offers an efficient solution for energy storage and conveyance. Hydrogen generated from excess renewable electricity can be conveyed through the API 5L steel-made pipelines that already exist. In recent years, there has been a growing demand for the transportation of hydrogen through existing gas pipelines. Therefore, numerical and experimental tests are required to verify and ensure the mechanical integrity of the API 5L steel pipelines that will be used for pressurized hydrogen transportation. Internal pressure loading is likely to accelerate hydrogen diffusion through the internal pipe wall and consequently accentuate the hydrogen embrittlement of steel pipelines. Furthermore, pre-cracked pipelines are susceptible to quick failure, mainly under a time-dependent cyclic pressure loading that drives fatigue crack propagation. Meanwhile, after several loading cycles, the initial cracks will propagate to a critical size. At this point, the remaining service life of the pipeline can be estimated, and inspection intervals can be determined. This paper focuses on the hydrogen embrittlement of API 5L steel-made pipeline under cyclic pressure loading. Pressurized hydrogen gas is transported through a network of pipelines where demands at consumption nodes vary periodically. The resulting pressure profile over time is considered a cyclic loading on the internal wall of a pre-cracked pipeline made of API 5L steel-grade material. Numerical modeling has allowed the prediction of fatigue crack evolution and estimation of the remaining service life of the pipeline. The developed methodology in this paper is based on the ASME B31.12 standard, which outlines the guidelines for hydrogen pipelines.

Keywords: hydrogen embrittlement, pipelines, transient flow, cyclic pressure, fatigue crack growth

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Authors: Binyam Teferi

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In this paper, a theoretical analysis of blood flow in the presence of thermal radiation and chemical reaction under the influence of time dependent magnetic field intensity has been studied. The unsteady non linear partial differential equations of blood flow considers time dependent stretching velocity, the energy equation also accounts time dependent temperature of vessel wall, and concentration equation includes time dependent blood concentration. The governing non linear partial differential equations of motion, energy, and concentration are converted into ordinary differential equations using similarity transformations solved numerically by applying ode45. MATLAB code is used to analyze theoretical facts. The effect of physical parameters viz., permeability parameter, unsteadiness parameter, Prandtl number, Hartmann number, thermal radiation parameter, chemical reaction parameter, and Schmidt number on flow variables viz., velocity of blood flow in the vessel, temperature and concentration of blood has been analyzed and discussed graphically. From the simulation study, the following important results are obtained: velocity of blood flow increases with both increment of permeability and unsteadiness parameter. Temperature of the blood increases in vessel wall as Prandtl number and Hartmann number increases. Concentration of the blood decreases as time dependent chemical reaction parameter and Schmidt number increases.

Keywords: stretching velocity, similarity transformations, time dependent magnetic field intensity, thermal radiation, chemical reaction

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Authors: Pradip Choudhury, Tapobrata Sanyal

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Effectiveness of Jute Geotextiles (JGT) in hill slope management now stands substantiated. The reasons of its efficacy are attributed to its bio-degradability, hygroscopic property and its thickness. Usually open weave JGT is used for slope management. Thickness of JGT helps in reducing the velocity of surface run-off, thus curbing the extent of migration of soil particles detached as a result of kinetic energy of rain-drops and also of wind effects. Initially JGT acts as cover of the surface of slope thus protect movement of loose soil particles. Hygroscopic property of jute effects overland storage of the flow. JGT acts as mulch and creates a congenial micro-climate that fosters quick growth of vegetation on bio-degradation. In fact JGT plays an important role in bio-remediation of slope-erosion problems. Considering the environmental aftermath, JGT is the preferred option in developed countries for surface soil conservation against erosion. In India JGT has not been tried in low temperature zones at high altitudes where temperature goes below the freezing point (even below - 25° Celsius). The behavior of JGT in such low-temperature zones is not precisely known. The 16th BRTF of Project Himank of Border Roads Organization (BRO) has recently taken the initiative to try two varieties of JGT , ie, 292 gsm and 500 gsm at two different places for hill slope management in Leh, a high altitude place of about 2,660 mtrs and 4900 mtrs above MSL respectively in Jammu & Kashmir where erosion is caused more as a result of rapid movement of sand particles due to high wind (wind erosion. Soil particles of the region formed naturally by weathering of fragile rocks are usually loosely bonded (non-cohesive), undergo dissociation with the rise in wind force and kinetic energy of rain drops and are blown away by wind. Open weave JGT interestingly was observed to contain the dissociated soil particles within its pores and lend stability the affected soil mass to a great extent thus preventing its movement by extraneous agents such as wind. The paper delineates about climatic factors, type of JGT used and the prevailing site conditions with an attempt to analyze the mechanism of functioning of JGT in low temperature zones.

Keywords: climate, erosion, jutegeotextile, stabilize

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Authors: Shiva Kumar G.

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The present study is to know the level of noises emanated from vehicles in intersections located in urban areas using Sound Level Meter and the possibility of reducing noise levels through traffic flow optimization. The main objective is to study traffic noise level of the Intersections located at on-going metro construction activities and which are away from metro construction activities. To compare traffic noise level between stop phase, go phase and drive phase at the Intersections. To study the effect of traffic noise level of directional movement of traffic and variation in noise level during day and night times. The range of Noise level observed at intersections is between 60 to 105 decibel. The noise level of stop and drive phases were minimum and almost same where go phase had maximum noise level. By comparing noise level of directional movement of traffic, it has been noticed that Vijayanagar intersection has no significant difference in their noise level and all other intersection has a significant difference in their noise level. By comparing noise level of stop, go and drive phase it has been noticed that there was a significant difference in noise level during peak hours compared to off-peak hour. By comparing noise level between Metro and Non-Metro construction activity intersections it has been noticed that there was a significant difference in noise level. By comparing noise level during day and night times, significant differences in noise level were observed at all intersections.

Keywords: noise, metro and non-metro intersections, traffic flow optimization, stop-go and drive phase

Procedia PDF Downloads 445

Authors: Glaucia Maricato

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Our research deals with specific use of DNA tests in Brazil – aimed at financial reparation for the institutionalized and otherwise scattered offspring of leprosy patients who, from the 1920s up through the 1980s, were subjected to compulsory internment in the 'hospital-colonies', specialized in the containment of Hansen’s disease. Through a social movement, the ex-patients themselves gained the right, in 2007, to financial compensations. At the moment, the movement is seeking reparation for the (now adult) children of these people as well. Many of these children grew up in orphanages, in adopted families, or do not have official documents to prove their family belonging. In 2011, a team of Brazilian geneticists had volunteered their services, applying DNA tests in order to ascertain the connection of certain individuals to an ex-internee of the leprosarium. We have accompanied the activities in four different ex-colonies in order to understand how the DNA test was being signified by those being tested, and how the test fit into already existent notions of family. Inspired in the writings of scholars such as Sheila Jasanoff and Helena Machado, we examine the possibility of a 'geneticization of family ties' when people are obliged to back their claim for human rights by producing legal proof based on blood tests. However, in like fashion to other ethnographic studies on this theme, we encountered among tested adults a number of creative strategies that allow for the co-existence of the idea of 'scientifically-based' blood ties alongside other more traditional ways of signifying kinship.

Keywords: human rights, social movements, DNA tests, Hansen's disease

Procedia PDF Downloads 119

Authors: Shima Soleimani, Steven Eckels

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One area of special importance for the surface-level study of heat exchangers is tubes with internal micro-fins (< 0.5 mm tall). Micro-finned surfaces are a kind of extended solid surface in which energy is exchanged with water that acts as the source or sink of energy. Significant performance gains are possible for either shell, tube, or double pipe heat exchangers if the best surfaces are identified. The parametric studies of micro-finned tubes that have appeared in the literature left some key parameters unexplored. Specifically, they ignored three-dimensional (3D) micro-fin configurations, conduction heat transfer in the fins, and conduction in the solid surface below the micro-fins. Thus, this study aimed at implementing a parametric study of 3D micro-finned tubes that considered micro-fine height and discontinuity features. A 3D conductive and convective heat-transfer simulation through coupled solid and periodic fluid domains is applied in a commercial package, ANSYS Fluent 19.1. The simulation is steady-state with turbulent water flow cooling the inner wall of a tube with micro-fins. The simulation utilizes a constant and uniform temperature on the tube outer wall. Performance is mapped for 18 different simulation cases, including a smooth tube using a realizable k-ε turbulence model at a Reynolds number of 48,928. Results compared the performance of 3D tubes with results for the similar two-dimensional (2D) one. Results showed that the micro-fine height has a greater impact on performance factors than discontinuity features in 3D micro-fin tubes. A transformed 3D micro-fin tube can enhance heat transfer, and pressure drops up to 21% and 56% compared to a 2D one, respectfully.

Keywords: three-dimensional micro-fin tube, heat transfer, friction factor, heat exchanger

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Authors: Marlene Rosa, Susana Lopes

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Board games have been used for different purposes in geriatric care, demonstrating good results for health in general. However, there is not a conceptual framework that can help professionals and researchers in this area to design intervention programs or to think about future studies in this area. The aim of this study was to provide a pilot collection of board games’ serious purposes in geriatric care, using a WHO framework for health and disability. Study cases were developed in seven geriatric residential institutions from the center region in Portugal that are included in AGILAB program. The AGILAB program is a serious game-based method to train and spread out the implementation of board games in geriatric care. Each institution provides 2-hours/week of experiences using TATI Hand Game for serious purposes and then fulfill questions about a study-case (player characteristics; explain changes in players health according to this game experience). Two independent researchers read the information and classified it according to the International Classification for Functioning and Disability (ICF) categories. Any discrepancy was solved in a consensus meeting. Results indicate an important variability in body functions and structures: specific mental functions (e.g., b140 Attention functions, b144 Memory functions), b156 Perceptual functions, b2 sensory functions and pain (e.g., b230 Hearing functions; b265 Touch function; b280 Sensation of pain), b7 neuromusculoskeletal and movement-related functions (e.g., b730 Muscle power functions; b760 Control of voluntary movement functions; b710 Mobility of joint functions). Less variability was found in activities and participation domains, such as purposeful sensory experiences (d110-d129) (e.g., d115 Listening), communication (d3), d710 basic interpersonal interactions, d920 recreation and leisure (d9200 Play; d9205 Socializing). Concluding, this framework designed from a brief gamed-based experience includes mental, perceptual, sensory, neuromusculoskeletal, and movement-related functions and participation in sensory, communication, and leisure domains. More studies, including different experiences and a high number of users, should be developed to provide a more comprehensive ICF framework for game-based experiences in geriatric care.

Keywords: board game, aging, framework, experience

Procedia PDF Downloads 115

Authors: Portia Murphy, Danica Vasic, Anoja W. Gunaratne, Encarnita Sitchon, Teresita Tugonon, Marou Ison, Antoinette Le Busque, Christelle Pagonis, Thomas J. Borody

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Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder that affects an estimated 11% of the population globally with the most predominant symptoms being abdominal pain, bloating and altered bowel movements. All age groups suffer from IBS although the prevalence of IBS decreases for age groups over 50 years. Women are more likely to suffer from IBS than men. IBS can be categorized into 3 groups based on the type of altered bowel movement: diarrhea-predominant IBS (IBS-D), constipation-predominant IBS (IBS-C) and IBS with mixed bowel habit (IBS-M). The contribution of the gut microbiome to the etiology of IBS is becoming increasingly recognized with rising use of anti-microbial agents. Previous studies on vancomycin and rifaximin used as monotherapy or in combination have been conducted mainly on IBS-C and showed marked improvements in the symptoms. According to our knowledge, no studies reported using these two combinations of antibiotics for IBS-D. Here, we report a consecutive cohort of 18 patients treated with both vancomycin and rifaximin for IBS-D. These patients’ records were reviewed retrospectively. In this cohort, patients ages were between 24-74 years (mean 44 years) and 9 were female. Baseline all patients had diarrhea, 4 with mucus and one with blood. Patients reported other symptoms were abdominal pain (n=11) bloating (n=9), flatulence (n=7), fatigue (n=4) and nausea (n=3). Patients treatments were personalized according to their symptom severity and tolerability and were treated with combination of rifaximin (500 - 3000mg/d) and vancomycin (500mg - 1500mg/d) for an ongoing period. Follow-ups were conducted between 2-32 weeks’ time. Of all patients, 89% patients reported improvement of the symptoms, 1 reported no change and 1 patient’s symptoms got worse. The mechanism of action for both vancomycin and rifaximin involves the inhibition of bacterial cell wall and protein synthesis respectively. The role of these medications in improving the symptoms of this cohort suggests that IBS-D may be microbiome infection driven. In this cohort, similar patient presentations to Clostridium difficile, as well as symptom improvement with the use of rifaximin and particularly vancomycin, suggest that the infectious agent may be an unidentified Clostridium. These preliminary results offer an alternative etiology for IBS-D not previously considered and open the avenue for new research.

Keywords: clostridium deficile, diarrhea predominant Irritable Bowel Syndrome, microbiome, vancomycin/rifaximin combination

Procedia PDF Downloads 116

Authors: D. Pogliana, A. Maso, N. Milani, D. Panzin, S. Rivaroli, J. Konin

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This case aims to identify the role of movement quality during the final stage of return to sport (RTS) in a male amateur football player 13 years old after passing the acute phase of the bilateral Osgood-Schlatter disease (OSD). The patient, after a year from passing the acute phase of OSD with the abstention of physical activity, reports bilateral anterior knee pain at the beginning of the football sport activity. Interventions: After the orthopedist check, who recommended physiotherapy sessions for the correction of motor patterns and the isometric reinforcement of the muscles of the quadriceps, the rehabilitation intervention was developed in 7 weeks through 14 sessions of neuro-motor training (NMT) with a frequency of two weekly sessions and six sessions of muscle-strengthening with a frequency of one weekly session. The sessions of NMT were carried out through free body exercises (or with overloads) with visual bio-feedback with the help of two cameras (one with anterior vision and one with lateral vision of the subject) and a big touch screen. The aim of these sessions of NMT was to modify the dysfunctional motor patterns evaluated by the 2D motion analysis test. The test was carried out at the beginning and at the end of the rehabilitation course and included five movements: single-leg squat (SLS), drop jump (DJ), single-leg hop (SLH), lateral shuffle (LS), and change of direction (COD). Each of these movements was evaluated through the video analysis of dynamic valgus knee, pelvic tilt, trunk control, shock absorption, and motor strategy. A free image analysis software (Kinovea) was then used to calculate scores. Results: Baseline assessment of the subject showed a total score of 59% on the right limb and 64% on the left limb (considering an optimal score above 85%) with large deficits in shock absorption capabilities, the presence of dynamic valgus knee, and dysfunctional motor strategies defined “quadriceps dominant.” After six weeks of training, the subject achieved a total score of 80% on the right limb and 86% on the left limb, with significant improvements in shock absorption capabilities, the presence of dynamic knee valgus, and the employment of more hip-oriented motor strategies on both lower limbs. The improvements shown in dynamic knee valgus, greater hip-oriented motor strategies, and improved shock absorption identified through six weeks of the NMT program can help a teenager amateur football player to manage the anterior knee pain during sports activity. In conclusion, NMT was a good choice to help a 13 years old male amateur football player to return to performance without pain after OSD and can also be used with all this type of athletes of the other teams' sports.

Keywords: movement analysis, neuro-motor training, knee pain, movement strategies

Procedia PDF Downloads 112