Search results for: wall shear stress (WSS)
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 5828

Search results for: wall shear stress (WSS)

518 Modelling Forest Fire Risk in the Goaso Forest Area of Ghana: Remote Sensing and Geographic Information Systems Approach

Authors: Bernard Kumi-Boateng, Issaka Yakubu

Abstract:

Forest fire, which is, an uncontrolled fire occurring in nature has become a major concern for the Forestry Commission of Ghana (FCG). The forest fires in Ghana usually result in massive destruction and take a long time for the firefighting crews to gain control over the situation. In order to assess the effect of forest fire at local scale, it is important to consider the role fire plays in vegetation composition, biodiversity, soil erosion, and the hydrological cycle. The occurrence, frequency and behaviour of forest fires vary over time and space, primarily as a result of the complicated influences of changes in land use, vegetation composition, fire suppression efforts, and other indigenous factors. One of the forest zones in Ghana with a high level of vegetation stress is the Goaso forest area. The area has experienced changes in its traditional land use such as hunting, charcoal production, inefficient logging practices and rural abandonment patterns. These factors which were identified as major causes of forest fire, have recently modified the incidence of fire in the Goaso area. In spite of the incidence of forest fires in the Goaso forest area, most of the forest services do not provide a cartographic representation of the burned areas. This has resulted in significant amount of information being required by the firefighting unit of the FCG to understand fire risk factors and its spatial effects. This study uses Remote Sensing and Geographic Information System techniques to develop a fire risk hazard model using the Goaso Forest Area (GFA) as a case study. From the results of the study, natural forest, agricultural lands and plantation cover types were identified as the major fuel contributing loads. However, water bodies, roads and settlements were identified as minor fuel contributing loads. Based on the major and minor fuel contributing loads, a forest fire risk hazard model with a reasonable accuracy has been developed for the GFA to assist decision making.

Keywords: forest, GIS, remote sensing, Goaso

Procedia PDF Downloads 458
517 Residential Building Facade Retrofit

Authors: Galit Shiff, Yael Gilad

Abstract:

The need to retrofit old buildings lies in the fact that buildings are responsible for the main energy use and CO₂ emission. Existing old structures are more dominant in their effect than new energy-efficient buildings. Nevertheless not every case of urban renewal that aims to replace old buildings with new neighbourhoods necessarily has a financial or sustainable justification. Façade design plays a vital role in the building's energy performance and the unit's comfort conditions. A retrofit façade residential methodology and feasibility applicative study has been carried out for the past four years, with two projects already fully renovated. The intention of this study is to serve as a case study for limited budget façade retrofit in Mediterranean climate urban areas. The two case study buildings are set in Israel. However, they are set in different local climatic conditions. One is in 'Sderot' in the south of the country, and one is in' Migdal Hahemek' in the north of the country. The building typology is similar. The budget of the projects is around $14,000 per unit and includes interventions at the buildings' envelope while tenants are living in. Extensive research and analysis of the existing conditions have been done. The building's components, materials and envelope sections were mapped, examined and compared to relevant updated standards. Solar radiation simulations for the buildings in their surroundings during winter and summer days were done. The energy rate of each unit, as well as the building as a whole, was calculated according to the Israeli Energy Code. The buildings’ facades were documented with the use of a thermal camera during different hours of the day. This information was superimposed with data about the electricity use and the thermal comfort that was collected from the residential units. Later in the process, similar tools were further used in order to compare the effectiveness of different design options and to evaluate the chosen solutions. Both projects showed that the most problematic units were the ones below the roof and the ones on top of the elevated entrance floor (pilotis). Old buildings tend to have poor insulation on those two horizontal surfaces which require treatment. Different radiation levels and wall sections in the two projects influenced the design strategies: In the southern project, there was an extreme difference in solar radiations levels between the main façade and the back elevation. Eventually, it was decided to invest in insulating the main south-west façade and the side façades, leaving the back north-east façade almost untouched. Lower levels of radiation in the northern project led to a different tactic: a combination of basic insulation on all façades, together with intense treatment on areas with problematic thermal behavior. While poor execution of construction details and bad installation of windows in the northern project required replacing them all, in the southern project it was found that it is more essential to shade the windows than replace them. Although the buildings and the construction typology was chosen for this study are similar, the research shows that there are large differences due to the location in different climatic zones and variation in local conditions. Therefore, in order to reach a systematic and cost-effective method of work, a more extensive catalogue database is needed. Such a catalogue will enable public housing companies in the Mediterranean climate to promote massive projects of renovating existing old buildings, drawing on minimal analysis and planning processes.

Keywords: facade, low budget, residential, retrofit

Procedia PDF Downloads 211
516 Histological Study on the Effect of Bone Marrow Transplantation Combined with Curcumin on Pancreatic Regeneration in Streptozotocin Induced Diabetic Rats

Authors: Manal M. Shehata, Kawther M. Abdel-Hamid, Nashwa A. Mohamed, Marwa H. Bakr, Maged S. Mahmoud, Hala M. Elbadre

Abstract:

Introduction: The worldwide rapid increase in diabetes poses a significant challenge to current therapeutic approaches. Therapeutic utility of bone marrow transplantation in diabetes is an attractive approach. However, the oxidative stress generated by hyperglycemia may hinder β-cell regeneration. Curcumin, is a dietary spice with antioxidant activity. Aim of work: The present study was undertaken to investigate the therapeutic potential of curcumin, bone marrow transplantation, and their combined effects in the reversal of experimental diabetes. Material and Methods: Fifty adult male healthy albino rats were included in the present study.They were divided into two groups: Group І: (control group) included 10 rats. Group П: (diabetic group): included 40 rats. Diabetes was induced by single intraperitoneal injection of streptozotocin (STZ). Group II will be further subdivided into four groups (10 rats for each): Group II-a (diabetic control). Group II-b: rats were received single intraperitoneal injection of bone marrow suspension (un-fractionated bone marrow cells) prepared from rats of the same family. Group II-c: rats were treated with curcumin orally by gastric intubation for 6 weeks. Group II-d: rats were received a combination of single bone marrow transplantation and curcumin for 6 weeks. After 6 weeks, blood glucose, insulin levels were measured and the pancreas from all rats were processed for Histological, Immunohistochemical and morphometric examination. Results: Diabetic group, showed progressive histological changes in the pancreatic islets. Treatment with either curcumin or bone marrow transplantation improved the structure of the islets and reversed streptozotocin-induced hyperglycemia and hypoinsulinemia. Combination of curcumin and bone marrow transplantation elicited more profound alleviation of streptozotocin-induced changes including islet regeneration and insulin secretion. Conclusion: The use of natural antioxidants combined with bone marrow transplantation to induce pancreatic regeneration is a promising strategy in the management of diabetes.

Keywords: diabtes, panceatic islets, bone marrow transplantation, curcumin

Procedia PDF Downloads 388
515 Study of the Design and Simulation Work for an Artificial Heart

Authors: Mohammed Eltayeb Salih Elamin

Abstract:

This study discusses the concept of the artificial heart using engineering concepts, of the fluid mechanics and the characteristics of the non-Newtonian fluid. For the purpose to serve heart patients and improve aspects of their lives and since the Statistics review according to world health organization (WHO) says that heart disease and blood vessels are the first cause of death in the world. Statistics shows that 30% of the death cases in the world by the heart disease, so simply we can consider it as the number one leading cause of death in the entire world is heart failure. And since the heart implantation become a very difficult and not always available, the idea of the artificial heart become very essential. So it’s important that we participate in the developing this idea by searching and finding the weakness point in the earlier designs and hoping for improving it for the best of humanity. In this study a pump was designed in order to pump blood to the human body and taking into account all the factors that allows it to replace the human heart, in order to work at the same characteristics and the efficiency of the human heart. The pump was designed on the idea of the diaphragm pump. Three models of blood obtained from the blood real characteristics and all of these models were simulated in order to study the effect of the pumping work on the fluid. After that, we study the properties of this pump by using Ansys15 software to simulate blood flow inside the pump and the amount of stress that it will go under. The 3D geometries modeling was done using SOLID WORKS and the geometries then imported to Ansys design modeler which is used during the pre-processing procedure. The solver used throughout the study is Ansys FLUENT. This is a tool used to analysis the fluid flow troubles and the general well-known term used for this branch of science is known as Computational Fluid Dynamics (CFD). Basically, Design Modeler used during the pre-processing procedure which is a crucial step before the start of the fluid flow problem. Some of the key operations are the geometry creations which specify the domain of the fluid flow problem. Next is mesh generation which means discretization of the domain to solve governing equations at each cell and later, specify the boundary zones to apply boundary conditions for the problem. Finally, the pre–processed work will be saved at the Ansys workbench for future work continuation.

Keywords: Artificial heart, computational fluid dynamic heart chamber, design, pump

Procedia PDF Downloads 459
514 Kinaesthetic Method in Apprenticeship Training: Support for Finnish Learning in Vocational Education

Authors: Inkeri Jääskeläinen

Abstract:

The purpose of this study is to shed light on what is it like to study in apprenticeship training using Finnish as second language. This study examines the stories and experiences of apprenticeship students learning and studying Finnish as part of their vocational studies. Also, this pilot study examines the effects of learning to pronounce Finnish through body motions and gestures. Many foreign students choose apprenticeships and start vocational training too early, while their language skills in Finnish are still very weak. Both duties at work and school assignments require reasonably good general language skills (B1.1) and, especially at work, language skills are also a safety issue. At work students should be able to simultaneously learn Finnish and do vocational studies in a noisy, demanding, and stressing environment. Learning and understanding new things is very challenging under these circumstances and sometimes students get exhausted and experience a lot of stress - which makes learning even more difficult. Students are different from each other and so are their ways to learn. Thereafter, one of the most important features of apprenticeship training and second language learning is good understanding of adult learners and their needs. Kinaesthetic methods are an effective way to support adult students’ cognitive skills and make learning more relaxing and fun. Empirical findings show that language learning can indeed be supported physical ways, by body motions and gestures. The method used here, named TFFL (Touch and Feel Foreign Languages), was designed to support adult language learning, to correct or prevent language fossilization and to help the student to manage emotions. Finnish is considered as a difficult language to learn, mostly because it is so different from nearly all other languages. Many learners complain that they are lost or confused and there is a need to find a way to simultaneously learn the language and to handle negative emotion which come from Finnish language and the learning process itself. Due to the nature of Finnish language good pronunciation skills are needed just to understand the way the language work. Movements (body movements etc.) are a natural part of many cultures but not Finnish – In Finland students have traditionally been expected to stay still and that is not a natural way for many foreign students. However, kinaesthetic TFFL method proved out to be a useful way to help some L2 students to feel phonemes, rhythm and intonation, to improve their Finnish and, thereby, also to successfully complete their vocational studies.

Keywords: Finnish, fossilization, interference, kinaesthetic method

Procedia PDF Downloads 108
513 The Role and Effects of Communication on Occupational Safety: A Review

Authors: Pieter A. Cornelissen, Joris J. Van Hoof

Abstract:

The interest in improving occupational safety started almost simultaneously with the beginning of the Industrial Revolution. Yet, it was not until the late 1970’s before the role of communication was considered in scientific research regarding occupational safety. In recent years the importance of communication as a means to improve occupational safety has increased. Not only as communication might have a direct effect on safety performance and safety outcomes, but also as it can be viewed as a major component of other important safety-related elements (e.g., training, safety meetings, leadership). And while safety communication is an increasingly important topic in research, its operationalization is often vague and differs among studies. This is not only problematic when comparing results, but also in applying these results to practice and the work floor. By means of an in-depth analysis—building on an existing dataset—this review aims to overcome these problems. The initial database search yielded 25.527 articles, which was reduced to a research corpus of 176 articles. Focusing on the 37 articles of this corpus that addressed communication (related to safety outcomes and safety performance), the current study will provide a comprehensive overview of the role and effects of safety communication and outlines the conditions under which communication contributes to a safer work environment. The study shows that in literature a distinction is commonly made between safety communication (i.e., the exchange or dissemination of safety-related information) and feedback (i.e. a reactive form of communication). And although there is a consensus among researchers that both communication and feedback positively affect safety performance, there is a debate about the directness of this relationship. Whereas some researchers assume a direct relationship between safety communication and safety performance, others state that this relationship is mediated by safety climate. One of the key findings is that despite the strongly present view that safety communication is a formal and top-down safety management tool, researchers stress the importance of open communication that encourages and allows employees to express their worries, experiences, views, and share information. This raises questions with regard to other directions (e.g., bottom-up, horizontal) and forms of communication (e.g., informal). The current review proposes a framework to overcome the often vague and different operationalizations of safety communication. The proposed framework can be used to characterize safety communication in terms of stakeholders, direction, and characteristics of communication (e.g., medium usage).

Keywords: communication, feedback, occupational safety, review

Procedia PDF Downloads 303
512 Physiological and Psychological Influence on Office Workers during Demand Response

Authors: Megumi Nishida, Naoya Motegi, Takurou Kikuchi, Tomoko Tokumura

Abstract:

In recent years, power system has been changed and flexible power pricing system such as demand response has been sought in Japan. The demand response system is simple in the household sector and the owner, decision-maker, can gain the benefits of power saving. On the other hand, the execution of the demand response in the office building is more complex than household because various people such as owners, building administrators and occupants are involved in making decisions. While the owners benefit from the demand saving, the occupants are forced to be exposed to demand-saved environment certain benefits. One of the reasons is that building systems are usually centralized control and each occupant cannot choose either participate demand response event or not, and contribution of each occupant to demand response is unclear to provide incentives. However, the recent development of IT and building systems enables the personalized control of office environment where each occupant can control the lighting level or temperature around him or herself. Therefore, it can be possible to have a system which each occupant can make a decision of demand response participation in office building. This study investigates the personal behavior upon demand response requests, under the condition where each occupant can adjust their brightness individually in their workspace. Once workers participate in the demand response, their task lights are automatically turned off. The participation rates in the demand response events are compared between four groups which are divided by different motivation, the presence or absence of incentives and the way of participation. The result shows that there are the significant differences of participation rates in demand response event between four groups. The way of participation has a large effect on the participation rate. ‘Opt-out’ group, where the occupants are automatically enrolled in a demand response event if they don't express non-participation, will have the highest participation rate in the four groups. The incentive has also an effect on the participation rate. This study also reports that the impact of low illumination office environment on the occupants, such as stress or fatigue. The electrocardiogram and the questionnaire are used to investigate the autonomic nervous activity and subjective symptoms about the fatigue of the occupants. There is no big difference between dim workspace during demand response event and bright workspace in autonomic nervous activity and fatigue.

Keywords: demand response, illumination, questionnaire, electrocardiogram

Procedia PDF Downloads 352
511 Carbendazim Toxicity and Ameliorative Effect of Vitamin E in African Giant Rats

Authors: A. O. Omonona, T. A. Jarikre

Abstract:

Increase specialization in agriculture and use of pesticides may inadvertently cause ecosystem degradation and eventually loss of biodiversity. The populations of numerous wildlife species have undergone a precipitous decline. Many of these problems have been attributed directly to habitat loss and over exploitation resulting from unregulated pesticide uses. Carbendazim a broad spectrum benzimidazole fungicide and a metabolite of benomyl, is used to control plant disease in cereals and fruit. The effect of carbendazim exposure and the ameliorative effect of tocopherol (vitamin E) were assessed on African giant rat AGR. Hematological, biochemical and histological changes were used to determine the health condition of the animals exposed to pesticide. Sixteen AGR were stabilized, weighed and then divided into four experimental groups (A to D). Two groups were pretreated with vitamin. Group A was exposed to carbendazim only, B- carbendazim + vitamin, C- vitamin only, and D- blank (control). Packed cell volume PCV was estimated by the microhematocrit method, Leucocyte and Platelet counts were determined using the hemocytometric method. Cholinesterase (AchE) and markers of oxidative stress were quantified, and tissue changes examined microscopically. There were no behavioral changes observed in the animals, but there was a decrease in body weight and abortion after 23 days of exposure to carbendazim. There was significant differences in the packed cell volume, the hemoglobin concentration and the red blood cell counts (p < 0.05). The increases in malonyl aldehyde MDA was significant (p < 0.05) in the pesticide intoxicated rats compared to control. Vitamin E supplementation reduced MDA level significantly (p < 0.05). There was a sharp remarkable decrease in acetylcholinesterase levels in the pesticide intoxicated rats (p < 0.05). Vitamin E supplementation normalise the AchE levels comparable to that in control. Grossly, the vital organs appeared normal in the pesticide exposed and control groups except moderate pulmonary congestion. Microscopically, there was severe diffuse hepatocellular swelling in carbendazim exposed group. The severity of hepatocellular injury was reduced in the rats with vitamin E. This study ascertained the toxic effect of carbendazim and antioxidative properties of vitamins in the Africa giant rat.

Keywords: African giant rat, antioxidant, carbendazim, pesticides, toxicity

Procedia PDF Downloads 364
510 Kinaesthetic Method in Apprenticeship Training: Support for Finnish Learning in Vocational Education and Training

Authors: Inkeri Jaaskelainen

Abstract:

The purpose of this study is to shed light on what it is like to study in apprenticeship training using Finnish as a second language. This study examines the stories and experiences of apprenticeship students learning and studying Finnish as part of their vocational studies. Also, this pilot study examines the effects of learning to pronounce Finnish through body motions and gestures. Many foreign students choose apprenticeships and start vocational training too early, while their language skills in Finnish are still very weak. Both duties at work and school assignments require reasonably good general language skills (B1.1), and, especially at work, language skills are also a safety issue. At work, students should be able to simultaneously learn Finnish and do vocational studies in a noisy, demanding, and stressful environment. Learning and understanding new things is very challenging under these circumstances and sometimes students get exhausted and experience a lot of stress - which makes learning even more difficult. Students are different from each other and so are their ways to learn. Thereafter, one of the most important features of apprenticeship training and second language learning is a good understanding of adult learners and their needs. Kinaesthetic methods are an effective way to support adult students’ cognitive skills and make learning more relaxing and fun. Empirical findings show that language learning can indeed be supported in physical ways, by body motions and gestures. The method used here, named TFFL (Touch and Feel Foreign Languages), was designed to support adult language learning, to correct or prevent language fossilization, and to help the student to manage emotions. Finnish is considered as a difficult language to learn, mostly because it is so different from nearly all other languages. Many learners complain that they are lost or confused and there is a need to find a way to simultaneously learn the language and to handle negative emotion that comes from the Finnish language and the learning process itself. Due to the nature of the Finnish language, good pronunciation skills are needed just to understand the way the language work. Movements (body movements etc.) are a natural part of many cultures, but not Finnish. In Finland, students have traditionally been expected to stay still, and that is not a natural way for many foreign students. However, the kinaesthetic TFFL method proved out to be a useful way to help some L2 students to feel phonemes, rhythm, and intonation, to improve their Finnish, and, thereby, also to successfully complete their vocational studies.

Keywords: Finnish, fossilization, interference, kinaesthetic method

Procedia PDF Downloads 140
509 Development and Experimental Validation of Coupled Flow-Aerosol Microphysics Model for Hot Wire Generator

Authors: K. Ghosh, S. N. Tripathi, Manish Joshi, Y. S. Mayya, Arshad Khan, B. K. Sapra

Abstract:

We have developed a CFD coupled aerosol microphysics model in the context of aerosol generation from a glowing wire. The governing equations can be solved implicitly for mass, momentum, energy transfer along with aerosol dynamics. The computationally efficient framework can simulate temporal behavior of total number concentration and number size distribution. This formulation uniquely couples standard K-Epsilon scheme with boundary layer model with detailed aerosol dynamics through residence time. This model uses measured temperatures (wire surface and axial/radial surroundings) and wire compositional data apart from other usual inputs for simulations. The model predictions show that bulk fluid motion and local heat distribution can significantly affect the aerosol behavior when the buoyancy effect in momentum transfer is considered. Buoyancy generated turbulence was found to be affecting parameters related to aerosol dynamics and transport as well. The model was validated by comparing simulated predictions with results obtained from six controlled experiments performed with a laboratory-made hot wire nanoparticle generator. Condensation particle counter (CPC) and scanning mobility particle sizer (SMPS) were used for measurement of total number concentration and number size distribution at the outlet of reactor cell during these experiments. Our model-predicted results were found to be in reasonable agreement with observed values. The developed model is fast (fully implicit) and numerically stable. It can be used specifically for applications in the context of the behavior of aerosol particles generated from glowing wire technique and in general for other similar large scale domains. Incorporation of CFD in aerosol microphysics framework provides a realistic platform to study natural convection driven systems/ applications. Aerosol dynamics sub-modules (nucleation, coagulation, wall deposition) have been coupled with Navier Stokes equations modified to include buoyancy coupled K-Epsilon turbulence model. Coupled flow-aerosol dynamics equation was solved numerically and in the implicit scheme. Wire composition and temperature (wire surface and cell domain) were obtained/measured, to be used as input for the model simulations. Model simulations showed a significant effect of fluid properties on the dynamics of aerosol particles. The role of buoyancy was highlighted by observation and interpretation of nucleation zones in the planes above the wire axis. The model was validated against measured temporal evolution, total number concentration and size distribution at the outlet of hot wire generator cell. Experimentally averaged and simulated total number concentrations were found to match closely, barring values at initial times. Steady-state number size distribution matched very well for sub 10 nm particle diameters while reasonable differences were noticed for higher size ranges. Although tuned specifically for the present context (i.e., aerosol generation from hotwire generator), the model can also be used for diverse applications, e.g., emission of particles from hot zones (chimneys, exhaust), fires and atmospheric cloud dynamics.

Keywords: nanoparticles, k-epsilon model, buoyancy, CFD, hot wire generator, aerosol dynamics

Procedia PDF Downloads 143
508 Influence of Strike-Slip Faulting in the Tectonic Evolution of North-Eastern Tunisia

Authors: Aymen Arfaoui, Abdelkader Soumaya, Ali Kadri, Noureddine Ben Ayed

Abstract:

The major contractional events characterized by strike-slip faulting, folding, and thrusting occurred in the Eocene, Late Miocene, and Quaternary along with the NE Tunisian domain between Bou Kornine-Ressas- Msella and Cap Bon Peninsula. During the Plio-Quaternary, the Grombalia and Mornag grabens show a maximum of collapse in parallelism with the NNW-SSE SHmax direction and developed as 3rd order extensive regions within a regional compressional regime. Using available tectonic and geophysical data supplemented by new fault-kinematic observations, we show that Cenozoic deformations are dominated by first order N-S faults reactivation, this sinistral wrench system is responsible for the formation of strike-slip duplexes, thrusts, folds, and grabens. Based on our new structural interpretation, the major faults of N-S Axis, Bou Kornine-Ressas-Messella (MRB), and Hammamet-Korbous (HK) form an N-S first order restraining stepover within a left-lateral strike-slip duplex. The N-S master MRB fault is dominated by contractional imbricate fans, while the parallel HK fault is characterized by a trailing of extensional imbricate fans. The Eocene and Miocene compression phases in the study area caused sinistral strike-slip reactivation of pre-existing N-S faults, reverse reactivation of NE-SW trending faults, and normal-oblique reactivation of NW-SE faults, creating a NE-SW to N-S trending system of east-verging folds and overlaps. Seismic tomography images reveal a key role for the lithospheric subvertical tear or STEP fault (Slab Transfer Edge Propagator) evidenced below this region on the development of the MRB and the HK relay zone. The presence of extensive syntectonic Pliocene sequences above this crustal scale fault may be the result of a recent lithospheric vertical motion of this STEP fault due to the rollback and lateral migration of the Calabrian slab eastward.

Keywords: Tunisia, strike-slip fault, contractional duplex, tectonic stress, restraining stepover, STEP fault

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507 The Contact between a Rigid Substrate and a Thick Elastic Layer

Authors: Nicola Menga, Giuseppe Carbone

Abstract:

Although contact mechanics has been widely focused on the study of contacts between half-space, it has been recently pointed out that in presence of finite thickness elastic layers the results of the contact problem show significant difference in terms of the main contact quantities (e.g. contact area, penetration, mean pressure, etc.). Actually, there exist a wide range of industrial application demanding for this kind of studies, such as seals leakage prediction or pressure-sensitive coatings for electrical applications. In this work, we focus on the contact between a rigid profile and an elastic layer of thickness h confined under two different configurations: rigid constrain and applied uniform pressure. The elastic problem at hand has been formalized following Green’s function method and then numerically solved by means of a matrix inversion. We study different contact conditions, both considering and neglecting adhesive interactions at the interface. This leads to different solution techniques: Adhesive contacts equilibrium solution is found, in term of contact area for given penetration, making stationary the total free energy of the system; whereas, adhesiveless contacts are addressed defining an equilibrium criterion, again on the contact area, relying on the fracture mechanics stress intensity factor KI. In particular, we make the KI vanish at the edges of the contact area, as peculiar for adhesiveless elastic contacts. The results are obtained in terms of contact area, penetration, and mean pressure for both adhesive and adhesiveless contact conditions. As expected, in the case of a uniform applied pressure the slab turns out much more compliant than the rigidly constrained one. Indeed, we have observed that the peak value of the contact pressure, for both the adhesive and adhesiveless condition, is much higher for the rigidly constrained configuration than in the case of applied uniform pressure. Furthermore, we observed that, for little contact area, both systems behave the same and the pull-off occurs at approximately the same contact area and mean contact pressure. This is an expected result since in this condition the ratio between the layers thickness and the contact area is very high and both layer configurations recover the half-space behavior where the pull-off occurrence is mainly controlled by the adhesive interactions, which are kept constant among the cases.

Keywords: contact mechanics, adhesion, friction, thick layer

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506 Structural Geology along the Jhakri-Wangtu Road (Jutogh Section) Himachal Pradesh, NW Higher Himalaya, India

Authors: Rajkumar Ghosh

Abstract:

The paper presents a comprehensive study of the structural analysis of the Chaura Thrust in Himachal Pradesh, India. The research focuses on several key aspects, including the activation timing of the Main Central Thrust (MCT) and the South Tibetan Detachment System (STDS), the identification and characterization of mylonitised zones through microscopic examination, and the understanding of box fold characteristics and their implications in the regional geology of the Himachal Himalaya. The primary objective of the study is to provide field documentation of the Chaura Thrust, which was previously considered a blind thrust with limited field evidence. Additionally, the research aims to characterize box folds and their signatures within the broader geological context of the Himachal Himalaya, document the temperature range associated with grain boundary migration (GBM), and explore the overprinting structures related to multiple sets of Higher Himalayan Out-of-Sequence Thrusts (OOSTs). The research methodology employed geological field observations and microscopic studies. Samples were collected along the Jhakri-Chaura transect at regular intervals of approximately 1 km to conduct strain analysis. Microstructural studies at the grain scale along the Jhakri-Wangtu transect were used to document the GBM-associated temperature range. The study reveals that the MCT activated in two parts, as did the STDS, and provides insights into the activation ages of the Main Boundary Thrust (MBT) and the Main Frontal Thrust (MFT). Under microscopic examination, the study identifies two mylonitised zones characterized by S-C fabric, and it documents dynamic and bulging recrystallization, as well as sub-grain formation. Various types of crenulated schistosity are observed in photomicrographs, including a rare occurrence where crenulation cleavage and sigmoid Muscovite are found juxtaposed. The study also notes the presence of S/SE-verging meso- and micro-scale box folds around Chaura, which may indicate structural upliftment. Kink folds near Chaura are visible, while asymmetric shear sense indicators in augen mylonite are predominantly observed under microscopic examination. Moreover, the research highlights the documentation of the Higher Himalayan Out-of-Sequence Thrust (OOST) in Himachal Pradesh, which activated the MCT and occurred within a zone south of the Main Central Thrust Upper (MCTU). The presence of multiple sets of OOSTs suggests a zigzag pattern of strain accumulation in the area. The study emphasizes the significance of understanding the overprinting structures associated with OOSTs. Overall, this study contributes to the understanding of the structural analysis of the Chaura Thrust and its implications in the regional geology of the Himachal Himalaya. The research underscores the importance of microscopic studies in identifying mylonitised zones and various types of crenulated schistosity. Additionally, the study documents the GBM-associated temperature range and provides insights into the activation of the Higher Himalayan Out-of-Sequence Thrust (OOST) in Himachal Pradesh. The findings of the study were obtained through geological field observations, microscopic studies, and strain analysis, offering valuable insights into the activation timing, mylonitization characteristics, and overprinting structures related to the Chaura Thrust and the broader tectonic framework of the region.

Keywords: Main Central Thrust, Jhakri Thrust, Chaura Thrust, Higher Himalaya, Out-of-Sequence Thrust, Sarahan Thrust

Procedia PDF Downloads 103
505 Experimental Study and Numerical Modelling of Failure of Rocks Typical for Kuzbass Coal Basin

Authors: Mikhail O. Eremin

Abstract:

Present work is devoted to experimental study and numerical modelling of failure of rocks typical for Kuzbass coal basin (Russia). The main goal was to define strength and deformation characteristics of rocks on the base of uniaxial compression and three-point bending loadings and then to build a mathematical model of failure process for both types of loading. Depending on particular physical-mechanical characteristics typical rocks of Kuzbass coal basin (sandstones, siltstones, mudstones, etc. of different series – Kolchuginsk, Tarbagansk, Balohonsk) manifest brittle and quasi-brittle character of failure. The strength characteristics for both tension and compression are found. Other characteristics are also found from the experiment or taken from literature reviews. On the base of obtained characteristics and structure (obtained from microscopy) the mathematical and structural models are built and numerical modelling of failure under different types of loading is carried out. Effective characteristics obtained from modelling and character of failure correspond to experiment and thus, the mathematical model was verified. An Instron 1185 machine was used to carry out the experiments. Mathematical model includes fundamental conservation laws of solid mechanics – mass, impulse, energy. Each rock has a sufficiently anisotropic structure, however, each crystallite might be considered as isotropic and then a whole rock model has a quasi-isotropic structure. This idea gives an opportunity to use the Hooke’s law inside of each crystallite and thus explicitly accounting for the anisotropy of rocks and the stress-strain state at loading. Inelastic behavior is described in frameworks of two different models: von Mises yield criterion and modified Drucker-Prager yield criterion. The damage accumulation theory is also implemented in order to describe a failure process. Obtained effective characteristics of rocks are used then for modelling of rock mass evolution when mining is carried out both by an open-pit or underground opening.

Keywords: damage accumulation, Drucker-Prager yield criterion, failure, mathematical modelling, three-point bending, uniaxial compression

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504 Data and Model-based Metamodels for Prediction of Performance of Extended Hollo-Bolt Connections

Authors: M. Cabrera, W. Tizani, J. Ninic, F. Wang

Abstract:

Open section beam to concrete-filled tubular column structures has been increasingly utilized in construction over the past few decades due to their enhanced structural performance, as well as economic and architectural advantages. However, the use of this configuration in construction is limited due to the difficulties in connecting the structural members as there is no access to the inner part of the tube to install standard bolts. Blind-bolted systems are a relatively new approach to overcome this limitation as they only require access to one side of the tubular section to tighten the bolt. The performance of these connections in concrete-filled steel tubular sections remains uncharacterized due to the complex interactions between concrete, bolt, and steel section. Over the last years, research in structural performance has moved to a more sophisticated and efficient approach consisting of machine learning algorithms to generate metamodels. This method reduces the need for developing complex, and computationally expensive finite element models, optimizing the search for desirable design variables. Metamodels generated by a data fusion approach use numerical and experimental results by combining multiple models to capture the dependency between the simulation design variables and connection performance, learning the relations between different design parameters and predicting a given output. Fully characterizing this connection will transform high-rise and multistorey construction by means of the introduction of design guidance for moment-resisting blind-bolted connections, which is currently unavailable. This paper presents a review of the steps taken to develop metamodels generated by means of artificial neural network algorithms which predict the connection stress and stiffness based on the design parameters when using Extended Hollo-Bolt blind bolts. It also provides consideration of the failure modes and mechanisms that contribute to the deformability as well as the feasibility of achieving blind-bolted rigid connections when using the blind fastener.

Keywords: blind-bolted connections, concrete-filled tubular structures, finite element analysis, metamodeling

Procedia PDF Downloads 158
503 Occupational Health Services (OHS) in Hong Kong Hospitals and the Experience of Nurses: A Mixed Methods Study

Authors: Wong Yat Cheung Maggie

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Occupational Safety and Health Ordinance (OS&HO) (Chap 509) was enacted in 1997, OHS in HK should be growing and maturing, with a holistic approach to occupational health and safety in the workplace including physical, mental, social and spiritual well-being. The question is “How effective are OHSPs in meeting the current needs of HK health workers?” This study was designed to explore the issue for the first time, to empirically analyse the views of those who work in the system. The study employed a mixed method approach to collect various data from Occupational Health Service Providers (OHSPs), Occupational Health Service Consumers (OHSC): Registered nurses working in the hospital setting. This study was designed in two phases and two stages. Phase I Stage I was a paper survey to collect the data on OHSP. Then Phase I Stage II was a follow-up interview. Phase II Stage I was a paper survey to collect the data on OHSC. Then Phase II Stage II was a follow-up focus group study on OHSC for further clarification of the Phase II and Stage I result. The Phase I result reflects HK OHSPs point of view and their experience in the existing OHS practice in the local hospitals. It reflects various styles of reporting systems, staff profiles background and resource in providing OHS in HK hospitals. However, the basic OHS concern is similar between hospitals. In general, the OHS policies and procedures are available on site even though they may have different foci. The Phase II result is reflecting the HKs OHSCs echoes the OHSP feedback at providing of OHS, OHS concern and related policies and procedure are available on site. However, the most significant feedback from the OHSC at Phase II Stage II shows, nurses experienced various OHS concern most commonly work stress, workplace harassment and back strain without formal or official report to the related parties. The lack of reporting was due to the management handling attitude, stakeholders’ compliance and term of definition still have room to be improved even the related policies and procedures are available on site.

Keywords: occupational health service, registered nurse, Hong Kong hospital, mixed method

Procedia PDF Downloads 335
502 A Study of Female Casino Dealers' Job Stress and Job Satisfaction: The Case of Macau

Authors: Xinrong Zong, Tao Zhang

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Macau is known as the Oriental Monte Carlo and its economy depends on gambling heavily. The dealer is the key position of the gambling industry, at the end of the fourth quarter of 2015, there were over 24,000 dealers among the 56,000 full-time employees in gambling industry. More than half of dealers were female. The dealer is also called 'Croupier', the main responsibilities of them are shuffling, dealing, processing chips, rolling dice game and inspecting play. Due to the limited land and small population of Macao, the government has not allowed hiring foreign domestic dealers since Macao developed temporary gambling industry. Therefore, local dealers enjoy special advantages but also bear the high stresses from work. From the middle of last year, with the reduced income of gambling, and the decline of mainland gamblers as well as VIP lounges, the working time of dealers increased greatly. Thus, many problems occurred in this condition, such as the rise of working pressures, psychological pressures and family-responsibility pressures, which may affect job satisfaction as well. Because of the less research of dealer satisfaction, and a lack of standing on feminine perspective to analyze female dealers, this study will focus on investigating the relationship between working pressure and job satisfaction from feminine view. Several issues will be discussed specifically: firstly, to understand current situation of the working pressures and job satisfactions of female dealers in different ages; secondly, to research if there is any relevance between working pressures and job satisfactions of female dealers in different ages; thirdly, to find out the relationship between dealers' working pressures and job satisfactions in different ages. This paper combined qualitative approach with quantitative approach selected samples by convenient sampling. The research showed the female dealers from diverse ages have different kinds of working pressures; second, job satisfactions of the female dealers in different ages are dissimilar; moreover, there is negative correlation between working pressure and job satisfaction of female dealer in different ages' groups; last but not the least, working pressure has a significant negative impact on job satisfaction. The research result will provide a reference value for the Macau gambling business. It is a pattern to improve dealers' working environment, to increase employees' job satisfaction, as well as to offer tourists a better service, which can help to attract more and more visitors from a good image of Macau gaming and tourism.

Keywords: female dealers, job satisfaction, working pressure, Macau

Procedia PDF Downloads 297
501 Analytical Model of Locomotion of a Thin-Film Piezoelectric 2D Soft Robot Including Gravity Effects

Authors: Zhiwu Zheng, Prakhar Kumar, Sigurd Wagner, Naveen Verma, James C. Sturm

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Soft robots have drawn great interest recently due to a rich range of possible shapes and motions they can take on to address new applications, compared to traditional rigid robots. Large-area electronics (LAE) provides a unique platform for creating soft robots by leveraging thin-film technology to enable the integration of a large number of actuators, sensors, and control circuits on flexible sheets. However, the rich shapes and motions possible, especially when interacting with complex environments, pose significant challenges to forming well-generalized and robust models necessary for robot design and control. In this work, we describe an analytical model for predicting the shape and locomotion of a flexible (steel-foil-based) piezoelectric-actuated 2D robot based on Euler-Bernoulli beam theory. It is nominally (unpowered) lying flat on the ground, and when powered, its shape is controlled by an array of piezoelectric thin-film actuators. Key features of the models are its ability to incorporate the significant effects of gravity on the shape and to precisely predict the spatial distribution of friction against the contacting surfaces, necessary for determining inchworm-type motion. We verified the model by developing a distributed discrete element representation of a continuous piezoelectric actuator and by comparing its analytical predictions to discrete-element robot simulations using PyBullet. Without gravity, predicting the shape of a sheet with a linear array of piezoelectric actuators at arbitrary voltages is straightforward. However, gravity significantly distorts the shape of the sheet, causing some segments to flatten against the ground. Our work includes the following contributions: (i) A self-consistent approach was developed to exactly determine which parts of the soft robot are lifted off the ground, and the exact shape of these sections, for an arbitrary array of piezoelectric voltages and configurations. (ii) Inchworm-type motion relies on controlling the relative friction with the ground surface in different sections of the robot. By adding torque-balance to our model and analyzing shear forces, the model can then determine the exact spatial distribution of the vertical force that the ground is exerting on the soft robot. Through this, the spatial distribution of friction forces between ground and robot can be determined. (iii) By combining this spatial friction distribution with the shape of the soft robot, in the function of time as piezoelectric actuator voltages are changed, the inchworm-type locomotion of the robot can be determined. As a practical example, we calculated the performance of a 5-actuator system on a 50-µm thick steel foil. Piezoelectric properties of commercially available thin-film piezoelectric actuators were assumed. The model predicted inchworm motion of up to 200 µm per step. For independent verification, we also modelled the system using PyBullet, a discrete-element robot simulator. To model a continuous thin-film piezoelectric actuator, we broke each actuator into multiple segments, each of which consisted of two rigid arms with appropriate mass connected with a 'motor' whose torque was set by the applied actuator voltage. Excellent agreement between our analytical model and the discrete-element simulator was shown for both for the full deformation shape and motion of the robot.

Keywords: analytical modeling, piezoelectric actuators, soft robot locomotion, thin-film technology

Procedia PDF Downloads 181
500 Transformation of ectA Gene From Halomonas elongata in Tomato Plant

Authors: Narayan Moger, Divya B., Preethi Jambagi, Krishnaveni C. K., Apsana M. R., B. R. Patil, Basvaraj Bagewadi

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Salinity is one of the major threats to world food security. Considering the requirement for salt tolerant crop plants in the present study was undertaken to clone and transferred the salt tolerant ectA gene from marine ecosystem into agriculture crop system to impart salinity tolerance. Ectoine is the compatible solute which accumulates in the cell membrane, is known to be involved in salt tolerance activity in most of the Halophiles. The present situation is insisting to development of salt tolerant transgenic lines to combat abiotic stress. In this background, the investigation was conducted to develop transgenic tomato lines by cloning and transferring of ectA gene is an ectoine derivative capable of enzymatic action for the production of acetyl-diaminobutyric acid. The gene ectA is involved in maintaining the osmotic balance of plants. The PCR amplified ectA gene (579bp) was cloned into T/A cloning vector (pTZ57R/T). The construct pDBJ26 containing ectA gene was sequenced by using gene specific forward and reverse primers. Sequence was analyzed using BLAST algorithm to check similarity of ectA gene with other isolates. Highest homology of 99.66 per cent was found with ectA gene sequences of isolates Halomonas elongata with the available sequence information in NCBI database. The ectA gene was further sub cloned into pRI101-AN plant expression vector and transferred into E. coli DH5α for its maintenance. Further pDNM27 was mobilized into A. tumefaciens LBA4404 through tri-parental mating system. The recombinant Agrobacterium containing pDNM27 was transferred into tomato plants through In planta plant transformation method. Out of 300 seedlings, co-cultivated only twenty-seven plants were able to well establish under the greenhouse condition. Among twenty-seven transformants only twelve plants showed amplification with gene specific primers. Further work must be extended to evaluate the transformants at T1 and T2 generations for ectoine accumulation, salinity tolerance, plant growth and development and yield.

Keywords: salinity, computable solutes, ectA, transgenic, in planta transformation

Procedia PDF Downloads 81
499 Classroom Curriculum That Includes Wisdom Skills

Authors: Brian Fleischli, Shani Robins

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In recent years, the implementation of wisdom skills, including emotional intelligence, mindfulness, empathy, compassion, gratitude, realism (Cognitive-Behavioral Therapy), and humility, within K-12 educational settings has demonstrated significant benefits in reducing stress, anxiety, anger, and conflict among students. This study summarizes the findings of research conducted over several years, showcasing the positive outcomes associated with teaching these skills to elementary and high school students. Additionally, this overview includes an updated synthesis of current literature concerning the application and effectiveness of training these skill sets in K-12 schools. The research outcomes highlight substantial improvements in student well-being and behavior. Demonstrated with treatment group students exhibiting notable reductions in anger, anxiety, depression, and disruptive behaviors compared to control groups. For instance, fourth-grade students showed enhanced empathy, responsibility, and attention, particularly benefiting those with lower initial scores on these measures. Specific interaction effects suggest that older students and males particularly benefit from these interventions, showcasing the nuanced impact of wisdom skill training across different demographics. Furthermore, this presentation emphasizes the critical role of Social and Emotional Learning (SEL) programs in addressing the multifaceted challenges faced by children and adolescents, including mental health issues, academic performance, and social behaviors. The integration of wisdom skills into school curricula not only fosters individual growth and emotional regulation but also enhances overall school climate and academic achievement. In conclusion, the findings contribute to the growing body of empirical evidence supporting the efficacy of teaching wisdom skills in educational settings. The success of these interventions underscores the potential for widespread implementation of evidence-based programs to promote emotional well-being and academic success among students nationwide.

Keywords: wisdom skills, CBT, cognitive behavioral training, mindfulness, empathy, anxiety

Procedia PDF Downloads 46
498 Cardiac Protective Effect of Olive Oil against Ischemia Reperfusion- Induced Cardiac Arrhythmias in Isolated Diabetic Rat Hearts

Authors: Ishfaq A. Bukhari, Bassem Yousef Sheikh, Abdulrahman Almotrefi, Osama Yousaf, Amer Mahmood

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Olive oil is the primary source of fat in the Mediterranean diet which is associated with a low mortality for cardiovascular disease. Olive oil is rich in monounsaturated fatty acids, and has been reported for variety of beneficial cardiovascular effects including blood pressure lowering, anti-platelet, anti-diabetic and anti-inflammatory effects. Growing number evidences from preclinical and clinical studies have shown that olive oil improves insulin resistance, decrease vessels stiffness and prevent thromboembolism. We evaluated the effects of olive against streptozotocin-induced physiological disorders in the animal models of diabetes and ischemia and reperfusion (I/R)- induced cardiac arrhythmias. Diabetes was induced in male rats with a single intraperitoneal injection of streptozotocin (60 mg/kg), rats were treated for two months with olive oil (1 ml/kg p.o). Control animals received saline. Blood glucose, body weight were monitored every 14 days. At the end of the treatment rats were sacrificed hearts were isolated for mounting on langedorff’s apparatus. The blood glucose and body weight was not significantly different in the control and olive treated animals. The control diabetic animals exhibited 100% incidence of I/R –induced ventricular fibrillation which was reduced to 0% with olive oil, treatment. The duration of ventricular fibrillation reduced from 98.8± 2.3 (control) to 0 seconds in the olive oil treated group. Diltiazem, a calcium channel blocker (1 µm/L) showed similar results and protected the I/R-induced cardiac disorders. The biochemical analysis of the cardiac tissues showed that diabetes and I/R produce marked pathological changes in the cardiomyocytes including decreased glutathione (GSH) and increased oxidative stress (Malondialdehyde; MDA). Pretreatment of animals with olive oil (1 ml/kg p.o) increased GSH and MDA levels. Olive oil also improved the diabetic-induced histopathological changes in the cardiomyocytes. These finding indicates that olive possesses cardiac protective properties. Further studies are under way in our lab to explore the mechanism of the cardio-protective effect of olive oil.

Keywords: diabeties, ischemia-reperfusion, olive oil, rats heart

Procedia PDF Downloads 464
497 Down Regulation of Smad-2 Transcription and TGF-B1 Signaling in Nano Sized Titanium Dioxide-Induced Liver Injury in Mice by Potent Antioxidants

Authors: Maha Z. Rizk, Sami A. Fattah, Heba M. Darwish, Sanaa A. Ali, Mai O. Kadry

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Although it is known that nano-TiO2 and other nanoparticles can induce liver toxicity, the mechanisms and the molecular pathogenesis are still unclear. The present study investigated some biochemical indices of nano-sized Titanium dioxide (TiO2 NPS) toxicity in mice liver and the ameliorative efficacy of individual and combined doses of idebenone, carnosine and vitamin E. Nano-anatase TiO2 (21 nm) was administered as a total oral dose of 2.2 gm/Kg daily for 2 weeks followed by the afore-mentioned antioxidants daily either individually or in combination for 1month. TiO2-NPS induced a significant elevation in serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and hepatic oxidative stress biomarkers [lipid peroxides (LP), and nitric oxide levels (NOX), while it significantly reduced glutathione reductase (GR), reduced glutathione (GSH) and glutathione peroxidase(GPX) levels. Moreover the quantitative RT-PCR analysis showed that nano-anatase TiO2 can significantly alter the mRNA and protein expressions of the fibrotic factors TGF-B1, VEGFand Smad-2. Histopathological examination of hepatic tissue reinforced the previous biochemical results. Our results also implied that inflammatory responses and liver injury may be involved in nano-anatase TiO2-induced liver toxicity Tumor necrosis factor-α (TNF-α) and Interleukin -6 (IL-6) and increased the percent of DNA damage which was assessed by COMET assay in addition to the apoptotic marker Caspase-3. Moreover mRNA gene expression observed by RT-PCR showed a significant overexpression in nuclear factor relation -2 (Nrf2), nuclear factor kappa beta (NF-Kβ) and the apoptotic factor (bax), and a significant down regulation in the antiapoptotic factor (bcl2) level. In conclusion idebenone, carnosine and vitamin E ameliorated the deviated previously mentioned parameters with variable degrees with the most pronounced role in alleviating the hazardous effect of TiO2 NPS toxicity following the combination regimen.

Keywords: Nano-anatase TiO2, TGF-B1, SMAD-2

Procedia PDF Downloads 425
496 Enhancing Wayfinding and User Experience in Hospital Environments: A Study of University Medical Centre Ljubljana

Authors: Nastja Utrosa, Matevz Juvancic

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Hospital buildings are complex public environments characterized by intricate functional arrangements and architectural layouts. Effective wayfinding is essential for patients, visitors, students, and staff. However, spatial orientation planning is often overlooked until after construction. While these environments meet functional needs, they frequently neglect the psychological aspects of user experience. This study investigates wayfinding within complex urban healthcare environments, focusing on the influences of spatial design, spatial cognition, and user experience. The inherent complexity of these environments, with extensive spatial dimensions and dispersed buildings, exacerbates the problem. Gradual expansions and additions contribute to disorientation and navigational difficulties for users. Effective route guidance in urban healthcare settings has become increasingly crucial. However, research on the environmental elements that influence wayfinding in such environments remains limited. To address this gap, we conducted a study at the University Medical Centre Ljubljana (UMCL), Slovenia's largest university hospital. Using a questionnaire, we assessed how individuals' perceptions and use of outdoor hospital spaces with a diverse sample (n=179). We evaluated the area’s usability by analyzing visit frequency, stops, modes of arrival, and parking patterns and examined the visitors' age distribution. Additionally, we investigated spatial aids and the use of color as an orientation element at three specific locations within the medical center. Our study explored the impact of color on entrance selection and the effectiveness of warm versus cool colors for wayfinding. Our findings highlight the significance of graphic adjustments in shaping perceptions of hospital outdoor spaces. Most participants preferred visually organized entrances, underscoring the importance of effective visual communication. Implementing these adaptations can substantially enhance the user experience, reducing stress and increasing satisfaction in hospital environments.

Keywords: hospital layout design, healthcare facilities, wayfinding, navigational aids, spatial orientation, color, signage

Procedia PDF Downloads 47
495 Fast Transient Workflow for External Automotive Aerodynamic Simulations

Authors: Christina Peristeri, Tobias Berg, Domenico Caridi, Paul Hutcheson, Robert Winstanley

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In recent years the demand for rapid innovations in the automotive industry has led to the need for accelerated simulation procedures while retaining a detailed representation of the simulated phenomena. The project’s aim is to create a fast transient workflow for external aerodynamic CFD simulations of road vehicles. The geometry used was the SAE Notchback Closed Cooling DrivAer model, and the simulation results were compared with data from wind tunnel tests. The meshes generated for this study were of two types. One was a mix of polyhedral cells near the surface and hexahedral cells away from the surface. The other was an octree hex mesh with a rapid method of fitting to the surface. Three different grid refinement levels were used for each mesh type, with the biggest total cell count for the octree mesh being close to 1 billion. A series of steady-state solutions were obtained on three different grid levels using a pseudo-transient coupled solver and a k-omega-based RANS turbulence model. A mesh-independent solution was found in all cases with a medium level of refinement with 200 million cells. Stress-Blended Eddy Simulation (SBES) was chosen for the transient simulations, which uses a shielding function to explicitly switch between RANS and LES mode. A converged pseudo-transient steady-state solution was used to initialize the transient SBES run that was set up with the SIMPLEC pressure-velocity coupling scheme to reach the fastest solution (on both CPU & GPU solvers). An important part of this project was the use of FLUENT’s Multi-GPU solver. Tesla A100 GPU has been shown to be 8x faster than an Intel 48-core Sky Lake CPU system, leading to significant simulation speed-up compared to the traditional CPU solver. The current study used 4 Tesla A100 GPUs and 192 CPU cores. The combination of rapid octree meshing and GPU computing shows significant promise in reducing time and hardware costs for industrial strength aerodynamic simulations.

Keywords: CFD, DrivAer, LES, Multi-GPU solver, octree mesh, RANS

Procedia PDF Downloads 116
494 Adaptive Strategies to Nutrient Deficiency of Doubled Diploid Citrumelo 4475: A Prospective Study Based on Structural, Ultrastructural, Physiological and Biochemical Parameters

Authors: J. Oustric, L. Berti, J. Santini

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Nowadays, the objective of durable agriculture, and in particular organic agriculture, is to reduce the level of fertilizer inputs used in crops. Limiting the quantity of fertilizer inputs would optimize the economical result and minimizing the environmental impact. Nutrient deficiency, particularly of a major nutrient (N, P, and K), can seriously affect fruit production and quality. In citrus crops, rootstock/scion combinations. In citrus crop, scion/rootstock combinations are used frequently to improve tolerance to various abiotic stresses. New rootstocks are needed to respond to these constraints, and the use of new tetraploid rootstocks better adapted to lower nutrient intake could offer a promising way forward. The aim of this work was to determine whether a better tolerance to nutrient deficiency could be observed in a doubled diploid seedling and whether this tolerance could be observed in common clementine scion if used as rootstocks. We selected diploid (CM2x) and doubled diploid (CM4x) Citrumelo 4475 seedlings and common clementine (C) grafted onto Citrumelo 4475 diploid (C/CM2x) and doubled diploid (C/CM4x) rootstocks. Nutrient deficiency effects on the seedlings and scion/rootstock combinations were analyzed by studying anatomical, structural and ultrastructural determinants (chlorosis, stomata, ostiole and cells and their organelles), photosynthetic properties (leaf net photosynthetic rate (Pₙₑₜ), stomatal conductance (gₛ), chlorophyll a fluorescence (Fᵥ/Fₘ)) and oxidative marker (malondialdehyde). Nutrient deficiency affected differently foliar tissues, physiological parameters, and oxidative metabolism in leaves of seedlings depending on their ploidy level and of common clementine scion depending on their rootstocks ploidy level. Both CM4x and C/CM4x presented lower foliar damages (chlorosis, chloroplasts, mitochondria, and plastoglobuli), photosynthesis processes alteration (Pₙₑₜ, gₛ, and Fᵥ/Fₘ), and malondialdehyde accumulation than CM2x and C/CM2x after nutrient deficiency. Doubled diploid Citrumelo 4475 can improve nutrient deficiency tolerance, and its use as a rootstock allows to confer this tolerance to the common clementine scion.

Keywords: nutrient deficiency, oxidative stress, photosynthesis, polyploid rootstocks

Procedia PDF Downloads 130
493 The Introduction of the Revolution Einstein’s Relative Energy Equations in Even 2n and Odd 3n Light Dimension Energy States Systems

Authors: Jiradeach Kalayaruan, Tosawat Seetawan

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This paper studied the energy of the nature systems by looking at the overall image throughout the universe. The energy of the nature systems was developed from the Einstein’s energy equation. The researcher used the new ideas called even 2n and odd 3n light dimension energy states systems, which were developed from Einstein’s relativity energy theory equation. In this study, the major methodology the researchers used was the basic principle ideas or beliefs of some religions such as Buddhism, Christianity, Hinduism, Islam, or Tao in order to get new discoveries. The basic beliefs of each religion - Nivara, God, Ether, Atman, and Tao respectively, were great influential ideas on the researchers to use them greatly in the study to form new ideas from philosophy. Since the philosophy of each religion was alive with deep insight of the physical nature relative energy, it connected the basic beliefs to light dimension energy states systems. Unfortunately, Einstein’s original relative energy equation showed only even 2n light dimension energy states systems (if n = 1,…,∞). But in advance ideas, the researchers multiplied light dimension energy by Einstein’s original relative energy equation and get new idea of theoritical physics in odd 3n light dimension energy states systems (if n = 1,…,∞). Because from basic principle ideas or beliefs of some religions philosophy of each religion, you had to add the media light dimension energy into Einstein’s original relative energy equation. Consequently, the simple meaning picture in deep insight showed that you could touch light dimension energy of Nivara, God, Ether, Atman, and Tao by light dimension energy. Since light dimension energy was transferred by Nivara, God, Ether, Atman and Tao, the researchers got the new equation of odd 3n light dimension energy states systems. Moreover, the researchers expected to be able to solve overview problems of all light dimension energy in all nature relative energy, which are developed from Eistein’s relative energy equation.The finding of the study was called 'super nature relative energy' ( in odd 3n light dimension energy states systems (if n = 1,…,∞)). From the new ideas above you could do the summation of even 2n and odd 3n light dimension energy states systems in all of nature light dimension energy states systems. In the future time, the researchers will expect the new idea to be used in insight theoretical physics, which is very useful to the development of quantum mechanics, all engineering, medical profession, transportation, communication, scientific inventions, and technology, etc.

Keywords: 2n light dimension energy states systems effect, Ether, even 2n light dimension energy states systems, nature relativity, Nivara, odd 3n light dimension energy states systems, perturbation points energy, relax point energy states systems, stress perturbation energy states systems effect, super relative energy

Procedia PDF Downloads 349
492 Post COVID-19 Multi-System Inflammatory Syndrome Masquerading as an Acute Abdomen

Authors: Ali Baker, Russel Krawitz

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This paper describes a rare occurrence where a potentially fatal complication of COVID-19 infection (MIS-A) was misdiagnosed as an acute abdomen. As most patients with this syndrome present with fever and gastrointestinal symptoms, they may inadvertently fall under the care of the surgical unit. However, unusual imaging findings and a poor response to anti-microbial therapy should prompt clinicians to suspect a non-surgical etiology. More than half of MIS-A patients require ICU admission and vasopressor support. Prompt referral to a physician is key, as the cornerstone of treatment is IVIG and corticosteroid therapy. A 32 year old woman presented with right sided abdominal pain and fevers. She had also contracted COVID-19 two months earlier. Abdominal examination revealed generalised right sided tenderness. The patient had raised inflammatory markers, but other blood tests were unremarkable. CT scan revealed extensive lymphadenopathy along the ileocolic chain. The patient proved to be a diagnostic dilemma. She was reviewed by several surgical consultants and discussed with several inpatient teams. Although IV antibiotics were commenced, the right sided abdominal pain, and fevers persisted. Pan-culture returned negative. A mild cholestatic derangement developed. On day 5, the patient underwent preparation for colonoscopy to assess for a potential intraluminal etiology. The following day, the patient developed sinus tachycardia and hypotension that was refractory to fluid resuscitation. That patient was transferred to ICU and required vasopressor support. Repeat CT showed peri-portal edema and a thickened gallbladder wall. On re-examination, the patient was Murphy’s sign positive. Biliary ultrasound was equivocal for cholecystitis. The patient was planned for diagnostic laparoscopy. The following morning, a marked rise in cardiac troponin was discovered, and a follow-up echocardiogram revealed moderate to severe global systolic dysfunction. The impression was post-COVID MIS with myocardial involvement. IVIG and Methylprednisolone infusions were commenced. The patient had a great response. Vasopressor support was weaned, and the patient was discharged from ICU. The patient continued to improve clinically with oral prednisolone, and was discharged on day 17. Although MIS following COVID-19 infection is well-described syndrome in children, only recently has it come to light that it can occur in adults. The exact incidence is unknown, but it is thought to be rare. A recent systematic review found only 221 cases of MIS-A, which could be included for analysis. Symptoms vary, but the most frequent include fever, gastrointestinal, and mucocutaneous. Many patients progress to multi-organ failure and require vasopressor support. 7% succumb to the illness. The pathophysiology of MIS is only partly understood. It shares similarities with Kawasaki disease, macrophage activation syndrome, and cytokine release syndrome. Importantly, by definition, the patient must have an absence of severe respiratory symptoms. It is thought to be due to a dysregulated immune response to the virus. Potential mechanisms include reduced levels of neutralising antibodies and autoreactive antibodies that promote inflammation. Further research into MIS-A is needed. Although rare, this potentially fatal syndrome should be considered in the unwell surgical patient who has recently contracted COVID-19 and poses a diagnostic dilemma.

Keywords: acute-abdomen, MIS, COVID-19, ICU

Procedia PDF Downloads 125
491 Balance Rigor, Relevance and Socio-Emotional Learning in Math

Authors: Abimbola Akintounde

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Supporting the social and emotional needs of young adolescents has become an emergent concern for schools around the world. Yet educators remain in a dilemma regarding the optimum approach for integrating social and emotional learning (SEL) into their content area instruction. The purpose of this study was to explore the perception of secondary students regarding their schoolwide SEL interventions. Twenty-four International Baccalaureate students in a final year mathematics course at an American Public Secondary School near Washington D. C. were randomly selected for participation in this study via an online electronic survey. The participants in this study used Likert-scale items to rate the effectiveness of the socio-emotional and character development programs being implemented at their schools. Respondents also ranked their preferred mode of delivery of social and emotional support programs. About 71% of the teenagers surveyed preferred SEL support rendered via interactive team-building activities and games, 42% of the high school students in the study ranked focus group discussions as their preferred format for SEL interventions, while only 13% of the respondents in the study regarded lectures and presentations as their preferred mode of SEL delivery. About one-fourth of the study participants agreed that explicit instruction was critical to enhancing students’ wellness, 79% agreed that SEL programs should foster less teacher talk, while 88% of the students indicated that student engagement was critical to their mental health. Eighty percent of the teenagers surveyed decried that the focus of their school-wide social and emotional programs was poorly prioritized. About two-thirds of the students agreed that social justice and equity issues should be embedded in their schools’ advisory programs. More than half of the respondents agitated for strategies for managing stress and their school workload. About 54% of the respondents also clamored for SEL programs that reinforce emotion regulation and coping strategies for anxiety. Based on the findings of this study, recommendations were proffered for best practices in the design and implementation of effective learner-friendly social and emotional development interventions.

Keywords: SEL, math anxiety, student support, emotion regulation, social awareness, self awareness, self management, relationship building

Procedia PDF Downloads 74
490 Multimedia Design in Tactical Play Learning and Acquisition for Elite Gaelic Football Practitioners

Authors: Michael McMahon

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The use of media (video/animation/graphics) has long been used by athletes, coaches, and sports scientists to analyse and improve performance in technical skills and team tactics. Sports educators are increasingly open to the use of technology to support coach and learner development. However, an overreliance is a concern., This paper is part of a larger Ph.D. study looking into these new challenges for Sports Educators. Most notably, how to exploit the deep-learning potential of Digital Media among expert learners, how to instruct sports educators to create effective media content that fosters deep learning, and finally, how to make the process manageable and cost-effective. Central to the study is Richard Mayers Cognitive Theory of Multimedia Learning. Mayers Multimedia Learning Theory proposes twelve principles that shape the design and organization of multimedia presentations to improve learning and reduce cognitive load. For example, the Prior Knowledge principle suggests and highlights different learning outcomes for Novice and Non-Novice learners, respectively. Little research, however, is available to support this principle in modified domains (e.g., sports tactics and strategy). As a foundation for further research, this paper compares and contrasts a range of contemporary multimedia sports coaching content and assesses how they perform as learning tools for Strategic and Tactical Play Acquisition among elite sports practitioners. The stress tests applied are guided by Mayers's twelve Multimedia Learning Principles. The focus is on the elite athletes and whether current coaching digital media content does foster improved sports learning among this cohort. The sport of Gaelic Football was selected as it has high strategic and tactical play content, a wide range of Practitioner skill levels (Novice to Elite), and also a significant volume of Multimedia Coaching Content available for analysis. It is hoped the resulting data will help identify and inform the future instructional content design and delivery for Sports Practitioners and help promote best design practices optimal for different levels of expertise.

Keywords: multimedia learning, e-learning, design for learning, ICT

Procedia PDF Downloads 106
489 Effects of Mindfulness Practice on Clinician Burnout: A Scoping Review

Authors: Hani Malik

Abstract:

Background: Clinician burnout is a growing phenomenon in current health systems worldwide. Increasing emotional exhaustion, depersonalisation, and reduced personal accomplishment threaten the effective delivery of healthcare. This can potentially be mitigated by mindfulness practice, which has shown promising results in reducing burnout, restoring compassion, and preventing moral injury in clinicians. Objectives: To conduct a scoping review and identify high-quality studies on mindfulness practice in clinician burnout, synthesize themes that emerge from these studies, and discuss the implications of the results to healthcare leadership and innovation. Methodology: A focused scoping review was carried out to investigate the effects of mindfulness practice on clinician burnout. High-ranking journals were targeted to analyse high-quality studies and synthesize common themes in the literature. Studies conducted on current, practicing physicians were included. Mindfulness practice of varying forms was the main intervention studied. Grey literature and studies conducted only on allied health personnel were excluded from this review. Analysis:31 studies were included in this scoping review. Mindfulness practice was found to decrease emotional exhaustion and depersonalisation while improving mood, responses to stress, and vigour. Self-awareness, compassion, and empathy were also increased in study participants. From this review, four themes emerged which include: innovations in mindfulness practice, mindfulness and positive psychology, the impact of mindfulness on work and patient care, and barriers and facilitators to clinician mindfulness practice. Conclusion: Mindfulness had widely been reported to benefit mental health and well-being, but the studies reviewed seemed to adopt a mono focus and omitted key considerations to healthcare leadership, systems-level culture, and practices. Mindfulness practice is a quintessential component of positive psychology and is inherently linked to effective leadership. A mindful and compassionate clinician leader will play a crucial role in addressing gaps in current practice, prioritise staff mental health, and provide a supportive platform for innovation.

Keywords: mindfulness practice, clinician burnout, healthcare leadership, COVID-19

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