Search results for: phase change
9714 Foundation Phase Teachers' Experiences of School Based Support Teams: A Case of Selected Schools in Johannesburg
Authors: Ambeck Celyne Tebid, Harry S. Rampa
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The South African Education system recognises the need for all learners including those experiencing learning difficulties, to have access to a single unified system of education. For teachers to be pedagogically responsive to an increasingly diverse learner population without appropriate support has been proven to be unrealistic. As such, this has considerably hampered interest amongst teachers, especially those at the foundation phase to work within an Inclusive Education (IE) and training system. This qualitative study aimed at investigating foundation phase teachers’ experiences of school-based support teams (SBSTs) in two Full-Service (inclusive schools) and one Mainstream public primary school in the Gauteng province of South Africa; with particular emphasis on finding ways to supporting them, since teachers claimed they were not empowered in their initial training to teach learners experiencing learning difficulties. Hence, SBSTs were created at school levels to fill this gap thereby, supporting teaching and learning by identifying and addressing learners’, teachers’ and schools’ needs. With the notion that IE may be failing because of systemic reasons, this study uses Bronfenbrenner’s (1979) ecosystemic as well as Piaget’s (1980) maturational theory to examine the nature of support and experiences amongst teachers taking individual and systemic factors into consideration. Data was collected using in-depth, face-to-face interviews, document analysis and observation with 6 foundation phase teachers drawn from 3 different schools, 3 SBST coordinators, and 3 school principals. Data was analysed using the phenomenological data analysis method. Amongst the findings of the study is that South African full- service and mainstream schools have functional SBSTs which render formal and informal support to the teachers; this support varies in quality depending on the socio-economic status of the relevant community where the schools are situated. This paper, however, argues that what foundation phase teachers settled for as ‘support’ is flawed; as well as how they perceive the SBST and its role is problematic. The paper conclude by recommending that, the SBST should consider other approaches at foundation phase teacher support such as, empowering teachers with continuous practical experiences on how to deal with real classroom scenarios, as well as ensuring that all support, be it on academic or non-academic issues should be provided within a learning community framework where the teacher, family, SBST and where necessary, community organisations should harness their skills towards a common goal.Keywords: foundation phase, full- service schools, inclusive education, learning difficulties, school-based support teams, teacher support
Procedia PDF Downloads 2279713 Non-Singular Gravitational Collapse of a Homogeneous Scalar Field in Deformed Phase Space
Authors: Amir Hadi Ziaie
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In the present work, we revisit the collapse process of a spherically symmetric homogeneous scalar field (in FRW background) minimally coupled to gravity, when the phase-space deformations are taken into account. Such a deformation is mathematically introduced as a particular type of noncommutativity between the canonical momenta of the scale factor and of the scalar field. In the absence of such deformation, the collapse culminates in a spacetime singularity. However, when the phase-space is deformed, we find that the singularity is removed by a non-singular bounce, beyond which the collapsing cloud re-expands to infinity. More precisely, for negative values of the deformation parameter, we identify the appearance of a negative pressure, which decelerates the collapse to finally avoid the singularity formation. While in the un-deformed case, the horizon curve monotonically decreases to finally cover the singularity, in the deformed case the horizon has a minimum value that this value depends on deformation parameter and initial configuration of the collapse. Such a setting predicts a threshold mass for black hole formation in stellar collapse and manifests the role of non-commutative geometry in physics and especially in stellar collapse and supernova explosion.Keywords: gravitational collapse, non-commutative geometry, spacetime singularity, black hole physics
Procedia PDF Downloads 3399712 Three Phase PWM Inverter for Low Rating Energy Efficient Systems
Authors: Nelson Lujara
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The paper presents a practical three-phase PWM inverter suitable for low voltage, low rating energy efficient systems. The work in the paper is conducted with the view to establishing the significance of the loss contribution from the PWM inverter in the determination of the complete losses of a photovoltaic (PV) array-powered induction motor drive water pumping system. Losses investigated include; conduction and switching loss of the devices and gate drive losses. It is found that the PWM inverter operates at a reasonable variable efficiency that does not fall below 92% depending on the load. The results between the simulated and experimental results for the system with or without a maximum power tracker (MPT) compares very well, within an acceptable range of 2% margin.Keywords: energy, inverter, losses, photovoltaic
Procedia PDF Downloads 6329711 Interpretation of Sweep Frequency Response Analysis (SFRA) Traces for the Earth Fault Damage Practically Simulated on the Power Transformer Specially Developed for Performing Sweep Frequency Response Analysis for Various Transformers
Authors: Akshay A. Pandya, B. R. Parekh
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This paper presents how earth fault damage in the transformer can be detected by Sweep Frequency Response Analysis (SFRA). The test methods used by the authors for presenting the results are described. The power transformer of rating 10 KVA, 11000 V/440 V, 3-phase, 50 Hz, Dyn11 has been specially developed in-house for carrying out SFRA testing by practically simulated various transformer damages on it. Earth fault has been practically simulated on HV “U” phase winding and LV “W” phase winding separately. The result of these simulated faults are presented and discussed. The motivation of this presented work is to extend the guideline approach; there are ideas to organize database containing collected measurement results. Since the SFRA interpretation is based on experience, such databases are thought to be of great importance when interpreting SFRA response. The evaluation of the SFRA responses against guidelines and experience have to be performed and conclusions regarding usefulness of each simulation has been drawn and at last overall conclusion has also been drawn.Keywords: earth fault damage, power transformer, practical simulation, SFRA traces, transformer damages
Procedia PDF Downloads 2789710 Multilevel Two-Phase Structuring in the Nitrogen Supersaturated AISI316 Stainless Steel
Authors: Tatsuhiko Aizawa, Yohei Suzuki, Tomomi Shiratori
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The austenitic stainless steel type AISI316 has been widely utilized as structural members and mold die substrates. The low temperature plasma nitriding has been utilized to harden these AISI316 members, parts, and dies without loss of intrinsic corrosion resistance to AISI316 stainless steels. Formation of CrN precipitates by normal plasma nitriding processes resulted in severe deterioration of corrosion toughness. Most previous studies on this low temperature nitriding of AISI316 only described the lattice expansion of original AISI316 lattices by the occupation of nitrogen interstitial solutes into octahedral vacancy sites, the significant hardening by nitrogen solid solution, and the enhancement of corrosion toughness. In addition to those engineering items, this low temperature nitriding process was characterized by the nitrogen supersaturation and nitrogen diffusion processes. The nitrogen supersaturated zones expanded by the nitrogen solute occupation to octahedral vacancy sites, and the un-nitrided surroundings to these zones were plastically strained to compensate for the mismatch strains across these nitrided and nitrided zones. The microstructure of nitrided AISI316 was refined by this plastic straining. The nitrogen diffusion process was enhanced to transport nitrogen solute atoms through the refined zone boundaries. This synergetic collaboration among the nitrogen supersaturation, the lattice expansion, the plastic straining, and the grain refinement yielded a thick nitrogen supersaturated layer. This synergetic relation was also characterized by the multilevel two-phase structuring. In XRD (X-Ray Diffraction) analysis, the nitrided AISI316 layer had - and -phases with the peak shifts from original lattices. After EBSD (Electron Back Scattering Diffraction) analysis, -grains and -grains homogeneously distributed in the nitrided layer. The scanning transmission electron microscopy (STEM) revealed that g-phase zone is N-poor cluster and a-phase zone is N-rich cluster. This proves that nitrogen supersaturated AISI316 stainless steels have multi-level two-phase structure in a very fine granular system.Keywords: AISI316 stainless steels, chemical affinity to nitrogen solutes, multi-level two-phase structuring, nitrogen supersaturation
Procedia PDF Downloads 979709 Fostering a Sense of Belonging in Hybrid Teams
Authors: Jam Harley
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The COVID-19 epidemic accelerated the speed of change in the workplace. Overnight, several individuals shifted from co-location in an office to hybrid or remote work. The pandemic also expedited and intensified the need to address persistent leadership and management concerns, including digital transformation, remote management, leading through fast change, anxiety, and uncertainty. Nonetheless, many leaders have failed to address the problems left behind by the epidemic. In a fundamental work devoted to comprehending what constitutes a human need, Maslow reiterates similar descriptors in his explanation of belongingness as the human need to be accepted, acknowledged, respected, and appreciated by a community of other individuals. This study aims to investigate the lived experiences of dispersed hybrid team members in order to find leadership best practices that improve team performance and retention through an increased individual’s sense of belonging.Keywords: organizational change, belonging, diversity, equity
Procedia PDF Downloads 509708 Image-Based UAV Vertical Distance and Velocity Estimation Algorithm during the Vertical Landing Phase Using Low-Resolution Images
Authors: Seyed-Yaser Nabavi-Chashmi, Davood Asadi, Karim Ahmadi, Eren Demir
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The landing phase of a UAV is very critical as there are many uncertainties in this phase, which can easily entail a hard landing or even a crash. In this paper, the estimation of relative distance and velocity to the ground, as one of the most important processes during the landing phase, is studied. Using accurate measurement sensors as an alternative approach can be very expensive for sensors like LIDAR, or with a limited operational range, for sensors like ultrasonic sensors. Additionally, absolute positioning systems like GPS or IMU cannot provide distance to the ground independently. The focus of this paper is to determine whether we can measure the relative distance and velocity of UAV and ground in the landing phase using just low-resolution images taken by a monocular camera. The Lucas-Konda feature detection technique is employed to extract the most suitable feature in a series of images taken during the UAV landing. Two different approaches based on Extended Kalman Filters (EKF) have been proposed, and their performance in estimation of the relative distance and velocity are compared. The first approach uses the kinematics of the UAV as the process and the calculated optical flow as the measurement; On the other hand, the second approach uses the feature’s projection on the camera plane (pixel position) as the measurement while employing both the kinematics of the UAV and the dynamics of variation of projected point as the process to estimate both relative distance and relative velocity. To verify the results, a sequence of low-quality images taken by a camera that is moving on a specifically developed testbed has been used to compare the performance of the proposed algorithm. The case studies show that the quality of images results in considerable noise, which reduces the performance of the first approach. On the other hand, using the projected feature position is much less sensitive to the noise and estimates the distance and velocity with relatively high accuracy. This approach also can be used to predict the future projected feature position, which can drastically decrease the computational workload, as an important criterion for real-time applications.Keywords: altitude estimation, drone, image processing, trajectory planning
Procedia PDF Downloads 1059707 Examining the Drivers to Sustainable Consumer Behavioral Intention in the Irish Aviation Industry
Authors: Amy Whelan
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This paper presents a comprehensive study on the drivers of sustainable consumer behavior in the Irish aviation industry. It aims to understand the underlying factors that facilitate or hinder a consumer's sustainable consumption habits related to aviation and its impact on the achievement of the United Nations' Sustainable Development Goals (SDGs). Adopted by all UN member states in 2015, the SDGs represent a global call to action to end poverty, protect the planet, and ensure peace and prosperity for all by 2030. The research takes a mixed methodology approach, combining focus groups in phase 1 and a survey in phase 2. The focus groups will be used to elicit qualitative data to understand the attitudes and perceptions of consumers toward sustainable aviation and tourism in Ireland. The survey in phase 2 will then provide a more comprehensive and quantifiable understanding of the topic. The results of this study will contribute to the advancement of knowledge in the field of sustainable tourism and will provide insights into the drivers of sustainable consumer behavior in the Irish aviation industry. It is expected that the findings of this research will have practical implications for industry stakeholders and policy-makers in their efforts to promote sustainable tourism and achieve the SDGs in Ireland.Keywords: aviation, consumer behaviour, marketing, sustainability
Procedia PDF Downloads 749706 Autonomous Control of Ultrasonic Transducer Drive System
Authors: Dong-Keun Jeong, Jong-Hyun Kim, Woon-Ha Yoon, Hee-Je Kim
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In order to automatically operate the ultrasonic transducer drive system for sonicating aluminum, this paper proposes the ultrasonic transducer sensorless control algorithm. The resonance frequency shift and electrical impedance change is a common phenomenon in the state of the ultrasonic transducer. The proposed control algorithm make use of the impedance change of ultrasonic transducer according to the environment between air state and aluminum alloy state, it controls the ultrasonic transducer drive system autonomous without a sensor. The proposed sensorless autonomous ultrasonic transducer control algorithm was experimentally verified using a 3kW prototype ultrasonic transducer drive system.Keywords: ultrasonic transducer drive system, impedance change, sensorless, autonomous control algorithm
Procedia PDF Downloads 3539705 Loop Heat Pipe Two-Phase Heat Transports: Guidelines for Technology Utilization
Authors: Triem T. Hoang
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Loop heat pipes (LHPs) are two-phase capillary-pumped heat transports. An appropriate working fluid is selected for the intended application temperature range. A closed-loop is evacuated to a high vacuum, back-filled partially with the working fluid, and then hermetically sealed under the fluid own pressure. Heat from a heat source conducts through the evaporator casing to vaporize liquid on the outer surface of the wick structure inside the evaporator. The generated vapor is compelled to vent out of the evaporator and into the vapor line for transport to the condenser assembly. There, heat is removed and rejected to a heat sink to condensed vapor back to liquid. The liquid exits the condenser and travels in the liquid line to return to the evaporator to complete the cycle. The circulation of fluid, and thus the heat transport in the LHP, is accomplished entirely by capillary action. The LHP contains no mechanical moving part to wear out or break down and, therefore possesses, reliability and a long life even without maintenance. In this paper, the author not only attempts to introduce the LHP technology in simplistic terms to those who are not familiar with it but also provides necessary technical information to potential users for the proper design and analysis of the LHP system.Keywords: two-phase heat transfer, loop heat pipe, capillary pumped technology, thermal-fluid modeling
Procedia PDF Downloads 1319704 Organic Paddy Production as a Coping Strategy to the Adverse Impact of Climate Change
Authors: Thapa M., J.P. Dutta, K.R. Pandey, R.R. Kattel
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Nepal is extremely vulnerable to the impact of climate change. To mitigate the climate change effects on agricultural production and productivity a range of adaptive strategies needs to be considered. The study was conducted to assess organic paddy production as a coping strategy to the adverse impact of climate change in Phulbari, VDC of Chitwan district. Altogether, 120 respondents (60 adopters of organic farming and 60 from non adopter) were selected using snowball technique of sampling. Pre- tested interview schedule, direct observation, focus group discussion, key informant interview as well as secondary data were used to collect the required information. Factors determining the adoption of organic farming were found to be age, year of schooling, training, frequency of extension contact, perception about climate change, economically active members and poor. A unit increase in these factors except poor would increase the probability of adoption by 4.1%, 7.5%, 7.8%, 43.1%, 41.8% and 7% respectively. However, for poor, it would decrease the probability of adoption of organic farming by 5.1%. Average organic matter content in the adopters' field was higher (2.7%) than the non-adopters' field (2.5%). The regression result showed that type of farmer, price and area under rice cultivation had positive and significant relationship with income; however dependency ratio had negative relationship. As the year of adoption of organic farming increases, the production of rice decline in the first two years then after goes on increasing but the cost of production goes on decreasing with the year of adoption. The respondents adapted to the changing climate through diversification of crops, use of resistance varieties and following good cropping pattern. Gradually growing consumers' awareness about health, preference towards quality food products are the strong points behind organic farming, whereas lacks of bio-fertilizers, lack of effective extension services, no price differentiation between organic and inorganic products were the weak points. There is need for more training and education to change the attitude of farmers and enhance their confidence about the role of organic farming to cope with climate change impact.Keywords: Organic farming, climate change, sustainable development
Procedia PDF Downloads 4499703 Bioclimatic Niches of Endangered Garcinia indica Species on the Western Ghats: Predicting Habitat Suitability under Current and Future Climate
Authors: Malay K. Pramanik
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In recent years, climate change has become a major threat and has been widely documented in the geographic distribution of many plant species. However, the impacts of climate change on the distribution of ecologically vulnerable medicinal species remain largely unknown. The identification of a suitable habitat for a species under climate change scenario is a significant step towards the mitigation of biodiversity decline. The study, therefore, aims to predict the impact of current, and future climatic scenarios on the distribution of the threatened Garcinia indica across the northern Western Ghats using Maximum Entropy (MaxEnt) modelling. The future projections were made for the year 2050 and 2070 with all Representative Concentration Pathways (RCPs) scenario (2.6, 4.5, 6.0, and 8.5) using 56 species occurrence data, and 19 bioclimatic predictors from the BCC-CSM1.1 model of the Intergovernmental Panel for Climate Change’s (IPCC) 5th assessment. The bioclimatic variables were minimised to a smaller number of variables after a multicollinearity test, and their contributions were assessed using jackknife test. The AUC value of 0.956 ± 0.023 indicates that the model performs with excellent accuracy. The study identified that temperature seasonality (39.5 ± 3.1%), isothermality (19.2 ± 1.6%), and annual precipitation (12.7 ± 1.7%) would be the major influencing variables in the current and future distribution. The model predicted 10.5% (19318.7 sq. km) of the study area as moderately to very highly suitable, while 82.60% (151904 sq. km) of the study area was identified as ‘unsuitable’ or ‘very low suitable’. Our predictions of climate change impact on habitat suitability suggest that there will be a drastic reduction in the suitability by 5.29% and 5.69% under RCP 8.5 for 2050 and 2070, respectively. Finally, the results signify that the model might be an effective tool for biodiversity protection, ecosystem management, and species re-habitation planning under future climate change scenarios.Keywords: Garcinia Indica, maximum entropy modelling, climate change, MaxEnt, Western Ghats, medicinal plants
Procedia PDF Downloads 1509702 Determining the Spatial Vulnerability Levels and Typologies of Coastal Cities to Climate Change: Case of Turkey
Authors: Mediha B. Sılaydın Aydın, Emine D. Kahraman
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One of the important impacts of climate change is the sea level rise. Turkey is a peninsula, so the coastal areas of the country are threatened by the problem of sea level rise. Therefore, the urbanized coastal areas are highly vulnerable to climate change. At the aim of enhancing spatial resilience of urbanized areas, this question arises: What should be the priority intervention subject in the urban planning process for a given city. To answer this question, by focusing on the problem of sea level rise, this study aims to determine spatial vulnerability typologies and levels of Turkey coastal cities based on morphological, physical and social characteristics. As a method, spatial vulnerability of coastal cities is determined by two steps as level and type. Firstly, physical structure, morphological structure and social structure were examined in determining spatial vulnerability levels. By determining these levels, most vulnerable areas were revealed as a priority in adaptation studies. Secondly, all parameters are also used to determine spatial typologies. Typologies are determined for coastal cities in order to use as a base for urban planning studies. Adaptation to climate change is crucial for developing countries like Turkey so, this methodology and created typologies could be a guide for urban planners as spatial directors and an example for other developing countries in the context of adaptation to climate change. The results demonstrate that the urban settlements located on the coasts of the Marmara Sea, the Aegean Sea and the Mediterranean respectively, are more vulnerable than the cities located on the Black Sea’s coasts to sea level rise.Keywords: climate change, coastal cities, vulnerability, urban land use planning
Procedia PDF Downloads 3159701 Irregular Meal Pattern: What Is the Impact on Weight
Authors: Maha Alhussain, Moira A Taylor, Ian A. Macdonald
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Background: It is well established that dietary composition has effects on metabolism and therefore impacts on health; however other aspects of diet, such as meal pattern, could also be important in both obesity management and promoting health. The present study investigated the effect of irregular meal frequency on anthropometric measurements and energy expenditure (EE) in healthy women. Design: 11 healthy weight women (18–40 years) were studied in a randomized crossover trial with two phases of 2 weeks each. In Phase 1, participants consumed either a regular meal pattern (6 meals/day) or an irregular meal pattern (varying from 3 to 9 meals/day). In Phase 2, participants followed the alternative meal pattern to that followed in Phase 1, after a 2-weeks washout period. In the two phases, identical foods were provided to a participant in amounts designed to keep body weight constant. Participants came to the laboratory after an overnight fast at the start and end of each phase. EE was measured in fasting state by indirect calorimetry. Postprandial EE was measured during the 3 h period after consumption of a milkshake, test drink. Results: There were no significant changes in body weight and anthropometric measurements after both meal pattern interventions. There was also no significant difference in mean daily energy intake between the regular and irregular meal pattern (2043 ±31 and 2099 ±33 respectively). EE in the fasting state showed no significant differences cross the experiment visits. There was a significant difference in Postprandial EE (measured for 3 h) by visit (P=0.04). Postprandial EE after the regular meal pattern was significantly higher than at baseline (P=0.002) or than after the irregular meal pattern (P= 0.04). Conclusion: Eating regularly for 14-day period significantly increases Postprandial EE which may contribute to weight loss and obesity management.Keywords: energy expenditure, energy intake, meal pattern, weight loss
Procedia PDF Downloads 4109700 Heat Transfer Enhancement Due to the Optimal Porosity in Plate Heat Exchangers with Sinusoidal Plates
Authors: Hossein Shokouhmand, Seyyed Mostafa Saadat
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In this paper, the effect of thermal dispersion on the performance of plate heat exchangers (PHEs) with sinusoidal plates is investigated. In this regard, the PHE is considered as a porous medium. The important property of a porous medium is porosity that is defined as the total fluid volume divided by the total volume occupied by the solid and fluid. A 2D array of parallel sinusoidal plates with laminar periodically developed forced convection and single-phase constant property flows and conduction in a homogenous solid phase in two directions is considered. The array of flows is counter and the flows heat capacities are equal. Numerical study of conjugate heat transfer and axial conduction in the solid phase with different plate thicknesses showed that there is an optimal porosity in which the efficiency of heat transfer is up to 4% more than the time when the porosity is near one. It is shown that the optimal porosity at zero angle of inclination depends both on Reynolds number and the aspect ratio. The optimal porosity increased while either the Reynolds number or waviness of plates increased.Keywords: plate heat exchanger, optimal porosity, efficiency, aspect ratio
Procedia PDF Downloads 3999699 Nursing System Development in Patients Undergoing Operation in 3C Ward
Authors: Darawan Augsornwan, Artitaya Sabangbal, Maneewan Srijan, Kanokarn Kongpitee, Lalida Petphai, Palakorn Surakunprapha
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Background: Srinagarind Hospital, Ward 3C, has patients with head and neck cancer, congenital urology anomalies such as hypospadis, cleft lip and cleft palate and congenital megacolon who need surgery. Undergoing surgery is a difficult time for patients/ family; they feel fear and anxiety. Nurses work closely with patients and family for 24 hours in the process of patients care, so should have the good nursing ability, innovation and an efficient nursing care system to promote patients self-care ability reducing suffering and preventing complications. From previous nursing outcomes we found patients did not receive appropriate information, could not take care of their wound, not early ambulation after the operation and lost follow-up. Objective: to develop the nursing system for patients who were undergoing an operation. Method: this is a participation action research. The sample population was 11 nurses and 60 patients. This study was divided into 3 phase: Phase 1. Situation review In this phase we review the clinical outcomes, the process of care from documents such as nurses note and interview nurses, patients and family about the process of care by nurses. Phase 2: focus group with 11 nurses, searching guideline for specific care, nursing care system then establish the protocol. This phase we have the protocol for giving information, teaching protocol and teaching record, leaflet for all of top five diseases, make video media to convey information, ambulation package and protocol for patients with head and neck cancer, patients zoning, primary nurse, improved job description for each staff level. Program to record number of patients, kind of medical procedures for showing nurses activity each day. Phase 3 implementation and evaluation. Result: patients/family receive appropriate information about deep breathing exercise, cough, early ambulation after the operation, information during the stay in the hospital. Patients family satisfaction is 95.04 percent, appropriate job description for a practical nurse, nurse aid, and worker. Nurses satisfaction is 95 percent. The complications can be prevented. Conclusion: the nursing system is the dynamic process using evidence to develop nursing care. The appropriate system depends on context and needs to keep an eye on every event.Keywords: development, nursing system, patients undergoing operation, 3C Ward
Procedia PDF Downloads 2599698 Characterization of Titanium -Niobium Alloys by Powder Metallurgy as İmplant
Authors: Eyyüp Murat Karakurt, Yan Huang, Mehmet Kaya, Hüseyin Demirtaş, Alper İncesu
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In this study, Ti-(x) Nb (at. %) master alloys (x:10, 20, and 30) were fabricated following a standard powder metallurgy route and were sintered at 1200 ˚C for 6h, under 300 MPa by powder metallurgy method. The effect of the Nb concentration in Ti matrix and porosity level was examined experimentally. For metallographic examination, the alloys were analysed by optical microscopy and energy dispersive spectrometry analysis. In addition, X-ray diffraction was performed on the alloys to determine which compound formed in the microstructure. The compression test was applied to the alloys to understand the mechanical behaviors of the alloys. According to Nb concentration in Ti matrix, the β phase increased. Also, porosity level played a crucial role on the mechanical performance of the alloys.Keywords: Nb concentration, porosity level, powder metallurgy, The β phase
Procedia PDF Downloads 2609697 Effect of Omega-3 Supplementation on Stunted Egyptian Children at Risk of Environmental Enteric Dysfunction: An Interventional Study
Authors: Ghada M. El-Kassas, Maged A. El Wakeel, Salwa R. El-Zayat
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Background: Environmental enteric dysfunction (EED) is asymptomatic villous atrophy of the small bowel that is prevalent in the developing world and is associated with altered intestinal function and integrity. Evidence has suggested that supplementary omega-3 might ameliorate this damage by reducing gastrointestinal inflammation and may also benefit cognitive development. Objective: We tested whether omega-3 supplementation improves intestinal integrity, growth, and cognitive function in stunted children predicted to have EED. Methodology: 100 Egyptian stunted children aged 1-5 years and 100 age and gender-matched normal children as controls. At the primary phase of the study, we assessed anthropometric measures and fecal markers such as myeloperoxidase (MPO), neopterin (NEO), and alpha-1-anti-trypsin (AAT) (as predictors of EED). Cognitive development was assessed (Bayley or Wechsler scores). Oral n-3 (omega-3) LC-PUFA at a dosage of 500 mg/d was supplemented to all cases and followed up for 6 months after which the 2ry phase of the study included the previous clinical, laboratory and cognitive assessment. Results: Fecal inflammatory markers were significantly higher in cases compared to controls. (MPO), (NEO) and (AAT) showed a significant decline in cases at the end of the 2ry phase (P < 0.001 for all). Omega-3 supplementation resulted also in a significant increase in mid-upper arm circumference (MUAC) (P < 0.01), weight for age z-score, and skinfold thicknesses (P< 0.05 for both). Cases showed significant improvement of cognitive function at phase 2 of the study. Conclusions: Omega-3 supplementation successfully improved intestinal inflammatory state related to EED. Also, some improvement of anthropometric and cognitive parameters showed obvious improvement with omega-3 supplementation.Keywords: cognitive functions, EED, omega-3, stunting
Procedia PDF Downloads 1459696 The Effect of Water Droplets Size in Fire Fighting Systems
Authors: Tassadit Tabouche
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Water sprays pattern, and water droplets size (different droplets diameter) are a key factors in the success of the suppression by water spray. The effects of the two important factors are investigated in this study. However, the fire extinguishing mechanism in such devices is not well understood due to the complexity of the physical and chemical interactions between water spray and fire plume. in this study, 3D, unsteady, two phase flow CFD simulation approach is introduced to provide a quantitative analysis of the complex interactions occurring between water spray and fire plume. Lagrangian Discrete Phase Model (DPM) was used for water droplets and a global one-step reaction mechanism in combustion model was used for fire plume.Keywords: droplets, water spray, water droplets size, 3D
Procedia PDF Downloads 5199695 Tectonic Inversion Manifestations in the Jebel Rouas-Ruissate (Northeastern Tunisia)
Authors: Aymen Arfaoui, Abdelkader Soumaya, Noureddine Ben Ayed
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The Rouas-Ruissateis a part of TunisianAtlas system. Analyze of the collected field data allowed us to propose a new interpretation for the main structural features of thisregion. Tectonic inversions along NE-SW trending fault of Zaghouan and holokinetic movements are the main factors controlling the architecture and geometry of the Jebel Rouas-Ruissate. The presence of breccias, Slumps, and synsedimentaryfaults along NW-SE and N-S trending major faults show that they were active during the Mesozoicextensionalepisodes. During Cenozoic inversion period, this structurewas shaped as imbricatefansformed byNE-SW trending thrust faults. The angularunconformitybetweenupperEocene- Oligocene, and Cretaceousdeposits reveals a compressive Eocene tectonic phase (called Pyrenean phase)occurred duringPaleocene-lower Eocene.The Triassicsaltsacted as a decollementlevel in the NE-SW trendingfault propagation fold model of the Rouas-Ruissate.The inversion of fault-slip data along the main regional fault zones reveals a coexistence of strike-slip and reverse fault stress regimes with NW-SE maximum horizontal stress(SHmax) characterizing the Alpine compressive phase (Upper Tortonian).Keywords: tunisia, imbricate fans, triassic decollement level, fault propagation fold
Procedia PDF Downloads 1479694 Effect of Y Addition on the Microstructure and Mechanical Properties of Sn-Zn Eutectic Alloy
Authors: Jung-Ho Moon, Tae Kwon Ha
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The effect of Yttrium addition on the microstructure and mechanical properties of Sn-Zn eutectic alloy, which has been attracting intensive focus as a Pb-free solder material, was investigated in this study. Phase equilibrium has been calculated by using FactSage® to evaluate the composition and fraction of equilibrium intermetallic compounds and construct a phase diagram. In the case of Sn-8.8 Zn eutectic alloy, the as-cast microstructure was typical lamellar. With addition of 0.25 wt. %Y, a large amount of pro-eutectic phases have been observed and various YZnx intermetallic compounds were expected to successively form during cooling. Hardness of Sn-8.8 Zn alloy was not affected by Y-addition and both alloys could be rolled by 90% at room temperature.Keywords: Sn-Zn eutectic alloy, yttrium, FactSage®, microstructure, mechanical properties
Procedia PDF Downloads 4639693 Hot Corrosion Behavior of Calcium Zirconate Modified YSZ Coatings
Authors: Naveed Ejaz, Liaqat Ali, Amer Nusair
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Thermal barrier coatings (TBCs) serve as thermal barriers against the high temperature of the hot regions of the aircraft turbine engines keeping the surface of the turbine blades, vanes and combustion chamber at comparatively lower temperature. The life of these coatings depends on many in-service environmental factors. Among these factors, the behavior of the bond coat as well as the top coat at high temperature aggravated by the corrosive environments having S, V, Na and Cl plays a key role. The incorporation of the 5-15% CaZrO3 in YSZ coatings was studied after hot corrosion in vanadium oxide environment. It was observed that the reactivity of the V gradually switched from Y to Ca making CaV2O4 instead of YVO4; the percentage of CaV2O4 increased with the increase of CaZrO3 in YSZ. It eventually prevented leaching out of the Y from YSZ leaving the YSZ without any harmful phase change. The thermal insulation was found to be improved in case of CaZrO3 incorporated YSZ coatings as compared to only YSZ coating.Keywords: hot corrosion, thermal barrier coatings, yttria stabilized zirconia, calcium zirconate
Procedia PDF Downloads 4009692 The Application of International Law in Terms of Earthlife Africa Johannesburg and Another v Minister of Energy and Others 65662/16 (2017) Case
Authors: M. van der Bank
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This study involves a legal analysis of the case Earthlife Africa Johannesburg v Minister of Environmental Affairs and Others. The case considered the impact of the Thabametsi Power Project if it operated to the expected year 2060 on the global climate and ever-changing climate, in South Africa. This judgment highlights the significance, place and principles of climate change and where climate change impacts the South African environmental law which has its founding principles in the Constitution of the Republic of South Africa, 1996. This paper seeks to examine the advances for climate change regulation and application in terms of international law, in South Africa, through a qualitative study involving comparative national and international case law. A literature review study was conducted to compare and contrast the various aspects of law in order to support the argument undertaken. The paper presents a detailed discussion of the current legislation and the position as it currently stands with reference to international law and interpretation. The relevant protections as outlined in the National Environmental Management Act will be discussed. It then proceeds to outline the potential liability of the Minister in the interpretation and application of international law.Keywords: climate change; environment, environmental review, international law; and principles
Procedia PDF Downloads 1189691 Design of a Real Time Heart Sounds Recognition System
Authors: Omer Abdalla Ishag, Magdi Baker Amien
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Physicians used the stethoscope for listening patient heart sounds in order to make a diagnosis. However, the determination of heart conditions by acoustic stethoscope is a difficult task so it requires special training of medical staff. This study developed an accurate model for analyzing the phonocardiograph signal based on PC and DSP processor. The system has been realized into two phases; offline and real time phase. In offline phase, 30 cases of heart sounds files were collected from medical students and doctor's world website. For experimental phase (real time), an electronic stethoscope has been designed, implemented and recorded signals from 30 volunteers, 17 were normal cases and 13 were various pathologies cases, these acquired 30 signals were preprocessed using an adaptive filter to remove lung sounds. The background noise has been removed from both offline and real data, using wavelet transform, then graphical and statistics features vector elements were extracted, finally a look-up table was used for classification heart sounds cases. The obtained results of the implemented system showed accuracy of 90%, 80% and sensitivity of 87.5%, 82.4% for offline data, and real data respectively. The whole system has been designed on TMS320VC5509a DSP Platform.Keywords: code composer studio, heart sounds, phonocardiograph, wavelet transform
Procedia PDF Downloads 4369690 Community Perception of Dynamics and Drivers of Land Cover Change around Pendjari Biosphere Reserve in Northern Benin
Authors: Jesugnon E. A. Kpodo, Aurlus D. Ouindeyama, Jan H. Sommer, Fifanou G. Vodouhe, Kolo Yeo
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Local communities are recognized as key actors for sustainable land use and to some extent actors driving land use land cover (LULC) change around protected areas. Understanding drivers responsible for these changes are very crucial for better policy decisions making. This study analyzed perception of 425 local people in 28 villages towards land cover change around Pendjari Biosphere Reserve using semi-structured questionnaire. 72.9% of local communities perceive land cover as degrading while 24.5% as improving and only 2.6% as stable during the five last years. Women perceived more land cover degradation than men do (84.1 vs. 67.1%). Local communities identified cultivated land expansion, logging, firewood collection, charcoal production, population growth, and poverty as the key drivers of declined LULC in the study area. Education has emerged as a significant factor influencing respondents’ perceptions of these drivers of LULC changes. Appropriate management measures and government policies should be implemented around Pendjari Biosphere Reserve to control drivers of LULC change.Keywords: local perceptions, LULC drivers, LULC dynamics, Pendjari Biosphere Reserve, rural livelihoods, sustainable resource management
Procedia PDF Downloads 1159689 Experimental Investigation of Nucleate Pool Boiling Heat Transfer Characteristics on Copper Surface with Laser-Textured Stepped Microstructures
Authors: Luvindran Sugumaran, Mohd Nashrul Mohd Zubir, Kazi Md Salim Newaz, Tuan Zaharinie Tuan Zahari, Suazlan Mt Aznam, Aiman Mohd Halil
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Due to the rapid advancement of integrated circuits and the increasing trend towards miniaturizing electronic devices, the amount of heat produced by electronic devices has consistently exceeded the maximum limit for heat dissipation. Currently, the two-phase cooling technique based on phase change pool boiling heat transfer has received a lot of attention because of its potential to fully utilize the latent heat of the fluid and produce a highly effective heat dissipation capacity while keeping the equipment's operating temperature within an acceptable range. There are numerous strategies available for the alteration of heating surfaces, but to find the best, simplest, and most dependable one remains a challenge. Lately, surface texturing via laser ablation has been used in a variety of investigations, demonstrating its significant potential for enhancing the pool boiling heat transfer performance. In this research, the nucleate pool boiling heat transfer performance of laser-textured copper surfaces of different patterns was investigated. The bare copper surface serves as a reference to compare the performance of laser-structured surfaces. It was observed that the heat transfer coefficients were increased with the increase of surface area ratio and the ratio of the peak-to-valley height of the microstructure. Laser machined grain structure produced extra nucleation sites, which ultimately caused the improved pool boiling performance. Due to an increase in nucleation site density and surface area, the enhanced nucleate boiling served as the primary heat transfer mechanism. The pool boiling performance of the laser-textured copper surfaces is superior to the bare copper surface in all aspects.Keywords: heat transfer coefficient, laser texturing, micro structured surface, pool boiling
Procedia PDF Downloads 829688 Energy Efficiency Analysis of Discharge Modes of an Adiabatic Compressed Air Energy Storage System
Authors: Shane D. Inder, Mehrdad Khamooshi
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Efficient energy storage is a crucial factor in facilitating the uptake of renewable energy resources. Among the many options available for energy storage systems required to balance imbalanced supply and demand cycles, compressed air energy storage (CAES) is a proven technology in grid-scale applications. This paper reviews the current state of micro scale CAES technology and describes a micro-scale advanced adiabatic CAES (A-CAES) system, where heat generated during compression is stored for use in the discharge phase. It will also describe a thermodynamic model, developed in EES (Engineering Equation Solver) to evaluate the performance and critical parameters of the discharge phase of the proposed system. Three configurations are explained including: single turbine without preheater, two turbines with preheaters, and three turbines with preheaters. It is shown that the micro-scale A-CAES is highly dependent upon key parameters including; regulator pressure, air pressure and volume, thermal energy storage temperature and flow rate and the number of turbines. It was found that a micro-scale AA-CAES, when optimized with an appropriate configuration, could deliver energy input to output efficiency of up to 70%.Keywords: CAES, adiabatic compressed air energy storage, expansion phase, micro generation, thermodynamic
Procedia PDF Downloads 3039687 Exploring Tree Growth Variables Influencing Carbon Sequestration in the Face of Climate Change
Authors: Funmilayo Sarah Eguakun, Peter Oluremi Adesoye
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One of the major problems being faced by human society is that the global temperature is believed to be rising due to human activity that releases carbon IV oxide (CO2) to the atmosphere. Carbon IV oxide is the most important greenhouse gas influencing global warming and possible climate change. With climate change becoming alarming, reducing CO2 in our atmosphere has become a primary goal of international efforts. Forest landsare major sink and could absorb large quantities of carbon if the trees are judiciously managed. The study aims at estimating the carbon sequestration capacity of Pinus caribaea (pine)and Tectona grandis (Teak) under the prevailing environmental conditions and exploring tree growth variables that influencesthe carbon sequestration capacity in Omo Forest Reserve, Ogun State, Nigeria. Improving forest management by manipulating growth characteristics that influences carbon sequestration could be an adaptive strategy of forestry to climate change. Random sampling was used to select Temporary Sample Plots (TSPs) in the study area from where complete enumeration of growth variables was carried out within the plots. The data collected were subjected to descriptive and correlational analyses. The results showed that average carbon stored by Pine and Teak are 994.4±188.3 Kg and 1350.7±180.6 Kg respectively. The difference in carbon stored in the species is significant enough to consider choice of species relevant in climate change adaptation strategy. Tree growth variables influence the capacity of the tree to sequester carbon. Height, diameter, volume, wood density and age are positively correlated to carbon sequestration. These tree growth variables could be manipulated by the forest manager as an adaptive strategy for climate change while plantations of high wood density speciescould be relevant for management strategy to increase carbon storage.Keywords: adaptation, carbon sequestration, climate change, growth variables, wood density
Procedia PDF Downloads 3739686 Climate Change Law and Transnational Corporations
Authors: Manuel Jose Oyson
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The Intergovernmental Panel on Climate Change (IPCC) warned in its most recent report for the entire world “to both mitigate and adapt to climate change if it is to effectively avoid harmful climate impacts.” The IPCC observed “with high confidence” a more rapid rise in total anthropogenic greenhouse gas emissions (GHG) emissions from 2000 to 2010 than in the past three decades that “were the highest in human history”, which if left unchecked will entail a continuing process of global warming and can alter the climate system. Current efforts, however, to respond to the threat of global warming, such as the United Nations Framework Convention on Climate Change and the Kyoto Protocol, have focused on states, and fail to involve Transnational Corporations (TNCs) which are responsible for a vast amount of GHG emissions. Involving TNCs in the search for solutions to climate change is consistent with an acknowledgment by contemporary international law that there is an international role for other international persons, including TNCs, and departs from the traditional “state-centric” response to climate change. Putting the focus of GHG emissions away from states recognises that the activities of TNCs “are not bound by national borders” and that the international movement of goods meets the needs of consumers worldwide. Although there is no legally-binding instrument that covers TNC activities or legal responsibilities generally, TNCs have increasingly been made legally responsible under international law for violations of human rights, exploitation of workers and environmental damage, but not for climate change damage. Imposing on TNCs a legally-binding obligation to reduce their GHG emissions or a legal liability for climate change damage is arguably formidable and unlikely in the absence a recognisable source of obligation in international law or municipal law. Instead a recourse to “soft law” and non-legally binding instruments may be a way forward for TNCs to reduce their GHG emissions and help in addressing climate change. Positive effects have been noted by various studies to voluntary approaches. TNCs have also in recent decades voluntarily committed to “soft law” international agreements. This development reflects a growing recognition among corporations in general and TNCs in particular of their corporate social responsibility (CSR). While CSR used to be the domain of “small, offbeat companies”, it has now become part of mainstream organization. The paper argues that TNCs must voluntarily commit to reducing their GHG emissions and helping address climate change as part of their CSR. One, as a serious “global commons problem”, climate change requires international cooperation from multiple actors, including TNCs. Two, TNCs are not innocent bystanders but are responsible for a large part of GHG emissions across their vast global operations. Three, TNCs have the capability to help solve the problem of climate change. Assuming arguendo that TNCs did not strongly contribute to the problem of climate change, society would have valid expectations for them to use their capabilities, knowledge-base and advanced technologies to help address the problem. It would seem unthinkable for TNCs to do nothing while the global environment fractures.Keywords: climate change law, corporate social responsibility, greenhouse gas emissions, transnational corporations
Procedia PDF Downloads 3439685 A Numerical Solution Based on Operational Matrix of Differentiation of Shifted Second Kind Chebyshev Wavelets for a Stefan Problem
Authors: Rajeev, N. K. Raigar
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In this study, one dimensional phase change problem (a Stefan problem) is considered and a numerical solution of this problem is discussed. First, we use similarity transformation to convert the governing equations into ordinary differential equations with its boundary conditions. The solutions of ordinary differential equation with the associated boundary conditions and interface condition (Stefan condition) are obtained by using a numerical approach based on operational matrix of differentiation of shifted second kind Chebyshev wavelets. The obtained results are compared with existing exact solution which is sufficiently accurate.Keywords: operational matrix of differentiation, similarity transformation, shifted second kind chebyshev wavelets, stefan problem
Procedia PDF Downloads 396