Search results for: connected impervious area.
6942 Study of Land Use Changes around an Archaeological Site Using Satellite Imagery Analysis: A Case Study of Hathnora, Madhya Pradesh, India
Authors: Pranita Shivankar, Arun Suryawanshi, Prabodhachandra Deshmukh, S. V. C. Kameswara Rao
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Many undesirable significant changes in landscapes and the regions in the vicinity of historically important structures occur as impacts due to anthropogenic activities over a period of time. A better understanding of such influences using recently developed satellite remote sensing techniques helps in planning the strategies for minimizing the negative impacts on the existing environment. In 1982, a fossilized hominid skull cap was discovered at a site located along the northern bank of the east-west flowing river Narmada in the village Hathnora. Close to the same site, the presence of Late Acheulian and Middle Palaeolithic tools have been discovered in the immediately overlying pebbly gravel, suggesting that the ‘Narmada skull’ may be from the Middle Pleistocene age. The reviews of recently carried out research studies relevant to hominid remains all over the world from Late Acheulian and Middle Palaeolithic sites suggest succession and contemporaneity of cultures there, enhancing the importance of Hathnora as a rare precious site. In this context, the maximum likelihood classification using digital interpretation techniques was carried out for this study area using the satellite imagery from Landsat ETM+ for the year 2006 and Landsat TM (OLI and TIRS) for the year 2016. The overall accuracy of Land Use Land Cover (LULC) classification of 2016 imagery was around 77.27% based on ground truth data. The significant reduction in the main river course and agricultural activities and increase in the built-up area observed in remote sensing data analysis are undoubtedly the outcome of human encroachments in the vicinity of the eminent heritage site.Keywords: cultural succession, digital interpretation, Hathnora, Homo Sapiens, Late Acheulian, Middle Palaeolithic
Procedia PDF Downloads 1726941 Perceptions of Community Members in Lephalale Area, Limpopo Province, Towards Water Conservation: Development of a Psychological Model
Authors: M. L. Seretlo-Rangata, T. Sodi, S. Govender
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Despite interventions by various governments to regulate water demand and address water scarcity, literature shows that billions of people across the world continue to struggle with access because not everyone contributes equally to conservation efforts. Behavioral factors such as individual and collective aspects of cognition and commitment have been found to play an important role in water conservation. The aim of the present study was to explore the perceptions of community members in the Lephalale area, Limpopo province, towards water conservation with a view to developing an explanatory psychological model on water conservation. Twenty (20) participants who relied on communal taps to access water in Lephalale Local Municipality, Limpopo province, were selected through purposeful sampling. In-depth, semi-structured, individual face-to-face interviews were used to gather data and were analyzed utilizing thematic content analysis (TCA). The research findings revealed that there are various psychological effects of water scarcity on communities, such as emotional distress, interpersonal conflicts and disruptions of daily activities of living. Additionally, the study results showed that the coping strategies developed by participants to deal with water scarcity included adopting alternative water use behaviors as well as adjusting current behaviors and lifestyles. Derived from the study findings, a psychological model of water conservation was developed. The model incorporates some ideas from the Value-Belief-Norm (VBN) theory and the Afrocentric theory. The model suggests that people’s worldviews, including their values, beliefs and culture, are significant determinants of their pro-environmental behaviors. The study concludes by recommending that authorities and policymakers should consider psychological factors when developing water management programs, strategies and interventions with the consultation of psychology experts.Keywords: water conservation, psychological model, pro-environmental behaviour, conservation psychology, water-use behaviour
Procedia PDF Downloads 716940 Census and Mapping of Oil Palms Over Satellite Dataset Using Deep Learning Model
Authors: Gholba Niranjan Dilip, Anil Kumar
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Conduct of accurate reliable mapping of oil palm plantations and census of individual palm trees is a huge challenge. This study addresses this challenge and developed an optimized solution implemented deep learning techniques on remote sensing data. The oil palm is a very important tropical crop. To improve its productivity and land management, it is imperative to have accurate census over large areas. Since, manual census is costly and prone to approximations, a methodology for automated census using panchromatic images from Cartosat-2, SkySat and World View-3 satellites is demonstrated. It is selected two different study sites in Indonesia. The customized set of training data and ground-truth data are created for this study from Cartosat-2 images. The pre-trained model of Single Shot MultiBox Detector (SSD) Lite MobileNet V2 Convolutional Neural Network (CNN) from the TensorFlow Object Detection API is subjected to transfer learning on this customized dataset. The SSD model is able to generate the bounding boxes for each oil palm and also do the counting of palms with good accuracy on the panchromatic images. The detection yielded an F-Score of 83.16 % on seven different images. The detections are buffered and dissolved to generate polygons demarcating the boundaries of the oil palm plantations. This provided the area under the plantations and also gave maps of their location, thereby completing the automated census, with a fairly high accuracy (≈100%). The trained CNN was found competent enough to detect oil palm crowns from images obtained from multiple satellite sensors and of varying temporal vintage. It helped to estimate the increase in oil palm plantations from 2014 to 2021 in the study area. The study proved that high-resolution panchromatic satellite image can successfully be used to undertake census of oil palm plantations using CNNs.Keywords: object detection, oil palm tree census, panchromatic images, single shot multibox detector
Procedia PDF Downloads 1606939 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 916938 Multi-Stage Optimization of Local Environmental Quality by Comprehensive Computer Simulated Person as Sensor for Air Conditioning Control
Authors: Sung-Jun Yoo, Kazuhide Ito
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In this study, a comprehensive computer simulated person (CSP) that integrates computational human model (virtual manikin) and respiratory tract model (virtual airway), was applied for estimation of indoor environmental quality. Moreover, an inclusive prediction method was established by integrating computational fluid dynamics (CFD) analysis with advanced CSP which is combined with physiologically-based pharmacokinetic (PBPK) model, unsteady thermoregulation model for analysis targeting micro-climate around human body and respiratory area with high accuracy. This comprehensive method can estimate not only the contaminant inhalation but also constant interaction in the contaminant transfer between indoor spaces, i.e., a target area for indoor air quality (IAQ) assessment, and respiratory zone for health risk assessment. This study focused on the usage of the CSP as an air/thermal quality sensor in indoors, which means the application of comprehensive model for assessment of IAQ and thermal environmental quality. Demonstrative analysis was performed in order to examine the applicability of the comprehensive model to the heating, ventilation, air conditioning (HVAC) control scheme. CSP was located at the center of the simple model room which has dimension of 3m×3m×3m. Formaldehyde which is generated from floor material was assumed as a target contaminant, and flow field, sensible/latent heat and contaminant transfer analysis in indoor space were conducted by using CFD simulation coupled with CSP. In this analysis, thermal comfort was evaluated by thermoregulatory analysis, and respiratory exposure risks represented by adsorption flux/concentration at airway wall surface were estimated by PBPK-CFD hybrid analysis. These Analysis results concerning IAQ and thermal comfort will be fed back to the HVAC control and could be used to find a suitable ventilation rate and energy requirement for air conditioning system.Keywords: CFD simulation, computer simulated person, HVAC control, indoor environmental quality
Procedia PDF Downloads 3616937 Policy Innovation and its Determinants: A Literature Review
Authors: Devasheesh Mathur
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The presentation reviews the literature on the phenomenon of policy innovation. Policy innovation refers to a shift in the way policy is made or executed. The paper covers comprehensively on the definition and also the various types of policy innovations. The emphasis is on the antecedents or the determinants of innovation in policies. The author has then made an effort to discover the knowledge gap in the field of policy innovation so as to identify the future scope of research. The objective is to lend more clarity in the area of policy innovation and help in creating a framework for policy-makers as well as academics.Keywords: literature review, policy innovation, determinants, antecedents
Procedia PDF Downloads 5856936 Quantitative Trait Loci Analysis in Multiple Sorghum Mapping Populations Facilitates the Dissection of Genetic Control of Drought Tolerance Related Traits in Sorghum [Sorghum bicolor (Moench)]
Authors: Techale B., Hongxu Dong, Mihrete Getinet, Aregash Gabizew, Andrew H. Paterson, Kassahun Bantte
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The genetic architecture of drought tolerance is expected to involve multiple loci that are unlikely to all segregate for alternative alleles in a single bi-parental population. Therefore, the identification of quantitative trait loci (QTL) that are expressed in diverse genetic backgrounds of multiple bi-parental populations provides evidence about both background-specific and common genetic variants. The purpose of this study was to map QTL related to drought tolerance using three connected mapping populations of different genetic backgrounds to gain insight into the genomic landscape of this important trait in elite Ethiopian germplasm. The three bi-parental populations, each with 207 F₂:₃ lines, were evaluated using an alpha lattice design with two replications under two moisture stress environments. Drought tolerance related traits were analyzed separately for each population using composite interval mapping, finding a total of 105 QTLs. All the QTLs identified from individual populations were projected on a combined consensus map, comprising a total of 25 meta QTLs for seven traits. The consensus map allowed us to deduce locations of a larger number of markers than possible in any individual map, providing a reference for genetic studies in different genetic backgrounds. The mQTL identified in this study could be used for marker-assisted breeding programs in sorghum after validation. Only one trait, reduced leaf senescence, showed a striking bias of allele distribution, indicating substantial standing variation among present varieties that might be employed in improving drought tolerance of Ethiopian and other sorghums.Keywords: Drought tolerance , Mapping populations, Meta QTL, QTL mapping, Sorghum
Procedia PDF Downloads 1806935 The Results of Longitudinal Water Quality Monitoring of the Brandywine River, Chester County, Pennsylvania by High School Students
Authors: Dina L. DiSantis
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Strengthening a sense of responsibility while relating global sustainability concepts such as water quality and pollution to a local water system can be achieved by teaching students to conduct and interpret water quality monitoring tests. When students conduct their own research, they become better stewards of the environment. Providing outdoor learning and place-based opportunities for students helps connect them to the natural world. By conducting stream studies and collecting data, students are able to better understand how the natural environment is a place where everything is connected. Students have been collecting physical, chemical and biological data along the West and East Branches of the Brandywine River, in Pennsylvania for over ten years. The stream studies are part of the advanced placement environmental science and aquatic science courses that are offered as electives to juniors and seniors at the Downingtown High School West Campus in Downingtown, Pennsylvania. Physical data collected includes: temperature, turbidity, width, depth, velocity, and volume of flow or discharge. The chemical tests conducted are: dissolved oxygen, carbon dioxide, pH, nitrates, alkalinity and phosphates. Macroinvertebrates are collected with a kick net, identified and then released. Students collect the data from several locations while traveling by canoe. In the classroom, students prepare a water quality data analysis and interpretation report based on their collected data. The summary of the results from longitudinal water quality data collection by students, as well as the strengths and weaknesses of student data collection will be presented.Keywords: place-based, student data collection, sustainability, water quality monitoring
Procedia PDF Downloads 1566934 Structural and Microstructural Analysis of White Etching Layer Formation by Electrical Arcing Induced on the Surface of Rail Track
Authors: Ali Ahmed Ali Al-Juboori, H. Zhu, D. Wexler, H. Li, C. Lu, J. McLeod, S. Pannila, J. Barnes
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A number of studies have focused on the formation mechanics of white etching layer and its origin in the railway operation. Until recently, the following hypotheses consider the precise mechanics of WELs formation: (i) WELs are the result of thermal process caused by wheel slip; (ii) WELs are mechanically induced by severe plastic deformation; (iii) WELs are caused by a combination of thermo-mechanical process. The mechanisms discussed above lead to occurrence of white etching layers on the area of wheel and rail contact. This is because the contact patch which is the active point of the wheel on the rail is exposed to highest shear stresses which result in localised severe plastic deformation; and highest rate of heat caused by wheel slipe during excessive traction or braking effort. However, if the WELs are not on the running band area, it would suggest that there is another cause of WELs formation. In railway system, particularly electrified railway, arcing phenomenon has been occurring more often and regularly on the rails. In electrified railway, the current is delivered to the train traction motor via contact wires and then returned to the station via the contact between the wheel and the rail. If the contact between the wheel and the rail is temporarily losing, due to dynamic vibration, entrapped dirt or water, lubricant effect or oxidation occurrences, high current can jump through the gap and results in arcing. The other resources of arcing also include the wheel passage the insulated joint and lightning on a train during bad weather. During the arcing, an extensive heat is generated and speared over a large area of top surface of rail. Thus, arcing is considered another heat source in the rail head (rather than wheel slipe) that results in microstructural changes and white etching layer formation. A head hardened (HH) rail steel, cut from a curved rail truck was used for the investigation. Samples were sectioned from a depth of 10 mm below the rail surface, where the material is considered to be still within the hardened layer but away from any microstructural changes on the top surface layer caused by train passage. These samples were subjected to electrical discharges by using Gas Tungsten Arc Welding (GTAW) machine. The arc current was controlled and moved along the samples surface in the direction of travel, as indicated by an arrow. Five different conditions were applied on the surface of the samples. Samples containing pre-existed WELs, taken from ex-service rail surface, were also considered in this study for comparison. Both simulated and ex-serviced WELs were characterised by advanced methods including SEM, TEM, TKD, EDS, XRD. Samples for TEM and TKFD were prepared by Focused Ion Beam (FIB) milling. The results showed that both simulated WELs by electrical arcing and ex-service WEL comprise similar microstructure. Brown etching layer was found with WELs and likely induced by a concurrent tempering process. This study provided a clear understanding of new formation mechanics of WELs which contributes to track maintenance procedure.Keywords: white etching layer, arcing, brown etching layer, material characterisation
Procedia PDF Downloads 1216933 The Impact of Adopting Cross Breed Dairy Cows on Households’ Income and Food Security in the Case of Dejen Woreda, Amhara Region, Ethiopia
Authors: Misganaw Chere Siferih
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This study assessed the impact of crossbreed dairy cows on household income and food security. The study area is found in Dejen Woreda, East Gojam Zone, and Amhara region of Ethiopia. Random sampling technique was used to obtain a sample of 80 crossbreed dairy cow owners and 176 indigenous dairy cow owners. The study employed food consumption score analytical framework to measure food security status of the household. No Statistical significant mean difference is found between crossbreed owners and indigenous owners. Logistic regression was employed to investigate crossbreed dairy cow adoption determinants , the result indicates that gender, education, labor number, land size cultivated, dairy cooperatives membership, net income and food security status of the household are statistically significant independent variables, which explained the binary dependent variable, crossbreed dairy cow adoption. Propensity score matching (PSM) was employed to analyze the impact of crossbreed dairy cow owners on farmers’ income and food security. The average net income of crossbreed dairy cow owners was found to be significantly higher than indigenous dairy cow owners. Estimates of average treatment effect of the treated (ATT) indicated that crossbreed dairy cow is able to impact households’ net income by 42%, 38.5%, 30.8% and 44.5% higher in kernel, radius, nearest neighborhood and stratification matching algorithms respectively as compared to indigenous dairy cow owners. However, estimates of average treatment of the treated (ATT) suggest that being an owner of crossbreed dairy cow is not able to affect food security significantly. Thus, crossbreed dairy cow enables farmers to increase income but not their food security in the study area. Finally, the study recommended establishing dairy cooperatives and advice farmers to become a member of them, attention to promoting the impact of crossbreed dairy cows and promotion of nutrition focus projects.Keywords: crossbreed dairy cow, net income, food security, propensity score matching
Procedia PDF Downloads 656932 Industrial Rock Characterization using Nuclear Magnetic Resonance (NMR): A Case Study of Ewekoro Quarry
Authors: Olawale Babatunde Olatinsu, Deborah Oluwaseun Olorode
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Industrial rocks were collected from a quarry site at Ewekoro in south-western Nigeria and analysed using Nuclear Magnetic Resonance (NMR) technique. NMR measurement was conducted on the samples in partial water-saturated and full brine-saturated conditions. Raw NMR data were analysed with the aid of T2 curves and T2 spectra generated by inversion of raw NMR data using conventional regularized least-squares inversion routine. Results show that NMR transverse relaxation (T2) signatures fairly adequately distinguish between the rock types. Similar T2 curve trend and rates at partial saturation suggests that the relaxation is mainly due to adsorption of water on micropores of similar sizes while T2 curves at full saturation depict relaxation decay rate as: 1/T2(shale)>1/ T2(glauconite)>1/ T2(limestone) and 1/T2(sandstone). NMR T2 distributions at full brine-saturation show: unimodal distribution in shale; bimodal distribution in sandstone and glauconite; and trimodal distribution in limestone. Full saturation T2 distributions revealed the presence of well-developed and more abundant micropores in all the samples with T2 in the range, 402-504 μs. Mesopores with amplitudes much lower than those of micropores are present in limestone, sandstone and glauconite with T2 range: 8.45-26.10 ms, 6.02-10.55 ms, and 9.45-13.26 ms respectively. Very low amplitude macropores of T2 values, 90.26-312.16 ms, are only recognizable in limestone samples. Samples with multiple peaks showed well-connected pore systems with sandstone having the highest degree of connectivity. The difference in T2 curves and distributions for the rocks at full saturation can be utilised as a potent diagnostic tool for discrimination of these rock types found at Ewekoro.Keywords: Ewekoro, NMR techniques, industrial rocks, characterization, relaxation
Procedia PDF Downloads 2976931 Design and Thermal Analysis of Power Harvesting System of a Hexagonal Shaped Small Spacecraft
Authors: Mansa Radhakrishnan, Anwar Ali, Muhammad Rizwan Mughal
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Many universities around the world are working on modular and low budget architecture of small spacecraft to reduce the development cost of the overall system. This paper focuses on the design of a modular solar power harvesting system for a hexagonal-shaped small satellite. The designed solar power harvesting systems are composed of solar panels and power converter subsystems. The solar panel is composed of solar cells mounted on the external face of the printed circuit board (PCB), while the electronic components of power conversion are mounted on the interior side of the same PCB. The solar panel with dimensions 16.5cm × 99cm is composed of 36 solar cells (each solar cell is 4cm × 7cm) divided into four parallel banks where each bank consists of 9 solar cells. The output voltage of a single solar cell is 2.14V, and the combined output voltage of 9 series connected solar cells is around 19.3V. The output voltage of the solar panel is boosted to the satellite power distribution bus voltage level (28V) by a boost converter working on a constant voltage maximum power point tracking (MPPT) technique. The solar panel module is an eight-layer PCB having embedded coil in 4 internal layers. This coil is used to control the attitude of the spacecraft, which consumes power to generate a magnetic field and rotate the spacecraft. As power converter and distribution subsystem components are mounted on the PCB internal layer, therefore it is mandatory to do thermal analysis in order to ensure that the overall module temperature is within thermal safety limits. The main focus of the overall design is on compactness, miniaturization, and efficiency enhancement.Keywords: small satellites, power subsystem, efficiency, MPPT
Procedia PDF Downloads 746930 Geopolymerization Methods for Clay Soils Treatment
Authors: Baba Hassane Ahmed Hisseini, Abdelkrim Bennabi, Rabah Hamzaoui, Lamis Makki, Gaetan Blanck
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Most of the clay soils are known as problematic soils due to their water content, which varies greatly over time. It is observed that they are used to be subject to shrinkage and swelling, thus causing a problem of stability on the structures of civil engineering construction work. They are often excavated and placed in a storage area giving rise to the opening of new quarries. This method has become obsolete today because to protect the environment, we are leading to think differently and opening the way to new research for the improvement of the performance of this type of clay soils to reuse them in the construction field. The solidification and stabilization technique is used to improve the properties of poor quality soils to transform them into materials with a suitable performance for a new use in the civil engineering field rather than to excavate them and store them in the discharge area. In our case, the polymerization method is used for bad clay soils classified as high plasticity soil class A4 according to the French standard NF P11-300, where classical treatment methods with cement or lime are not efficient. Our work concerns clay soil treatment study using raw materials as additives for solidification and stabilization. The geopolymers are synthesized by aluminosilicates materials like fly ash, metakaolin, or blast furnace slag and activated by alkaline solution based on sodium hydroxide (NaOH), sodium silicate (Na2SiO3) or a mixture of both of them. In this study, we present the mechanical properties of the soil clay (A4 type) evolution with geopolymerisation methods treatment. Various mix design of aluminosilicates materials and alkaline solutions were carried at different percentages and different curing times of 1, 7, and 28 days. The compressive strength of the untreated clayey soil could be increased from simple to triple. It is observed that the improvement of compressive strength is associated with a geopolymerization mechanism. The highest compressive strength was found with metakaolin at 28 days.Keywords: treatment and valorization of clay-soil, solidification and stabilization, alkali-activation of co-product, geopolymerization
Procedia PDF Downloads 1616929 A CORDIC Based Design Technique for Efficient Computation of DCT
Authors: Deboraj Muchahary, Amlan Deep Borah Abir J. Mondal, Alak Majumder
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A discrete cosine transform (DCT) is described and a technique to compute it using fast Fourier transform (FFT) is developed. In this work, DCT of a finite length sequence is obtained by incorporating CORDIC methodology in radix-2 FFT algorithm. The proposed methodology is simple to comprehend and maintains a regular structure, thereby reducing computational complexity. DCTs are used extensively in the area of digital processing for the purpose of pattern recognition. So the efficient computation of DCT maintaining a transparent design flow is highly solicited.Keywords: DCT, DFT, CORDIC, FFT
Procedia PDF Downloads 4786928 Vulnerability of Steel Moment-Frame Buildings with Pinned and, Alternatively, with Semi-Rigid Connections
Authors: Daniel Llanes, Alfredo Reyes, Sonia E. Ruiz, Federico Valenzuela Beltran
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Steel frames have been used in building construction for more than one hundred years. Beam-column may be connected to columns using either stiffened or unstiffened angles at the top and bottom beam flanges. Designers often assume that these assemblies acted as “pinned” connections for gravity loads and that the stiffened connections would act as “fixed” connections for lateral loads. Observation of damages sustained by buildings during the 1994 Northridge earthquake indicated that, contrary to the intended behavior, in many cases, brittle fractures initiated within the connections at very low levels of plastic demand, and in some cases, while the structures remained essentially elastic. Due to the damage presented in these buildings other type of alternative connections have been proposed. According to a research funded by the Federal Emergency Management Agency (FEMA), the screwed connections have better performance when they are subjected to cyclic loads, but at the same time, these connections have some degree of flexibility. Due to this situation, some researchers ventured into the study of semi-rigid connections. In the present study three steel buildings, constituted by regular frames are analyzed. Two types of connections are considered: pinned and semi-rigid connections. With the aim to estimate their structural capacity, a number of incremental dynamic analyzes are performed. 3D structural models are used for the analyses. The seismic ground motions were recorded on sites near Los Angeles, California, where the structures are supposed to be located. The vulnerability curves of the building are obtained in terms of maximum inter-story drifts. The vulnerability curves (which correspond to the models with two different types of connections) are compared, and its implications on its structural design and performance is discussed.Keywords: steel frame Buildings, vulnerability curves, semi-rigid connections, pinned connections
Procedia PDF Downloads 2256927 Application of Hydrological Engineering Centre – River Analysis System (HEC-RAS) to Estuarine Hydraulics
Authors: Julia Zimmerman, Gaurav Savant
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This study aims to evaluate the efficacy of the U.S. Army Corp of Engineers’ River Analysis System (HEC-RAS) application to modeling the hydraulics of estuaries. HEC-RAS has been broadly used for a variety of riverine applications. However, it has not been widely applied to the study of circulation in estuaries. This report details the model development and validation of a combined 1D/2D unsteady flow hydraulic model using HEC-RAS for estuaries and they are associated with tidally influenced rivers. Two estuaries, Galveston Bay and Delaware Bay, were used as case studies. Galveston Bay, a bar-built, vertically mixed estuary, was modeled for the 2005 calendar year. Delaware Bay, a drowned river valley estuary, was modeled from October 22, 2019, to November 5, 2019. Water surface elevation was used to validate both models by comparing simulation results to NOAA’s Center for Operational Oceanographic Products and Services (CO-OPS) gauge data. Simulations were run using the Diffusion Wave Equations (DW), the Shallow Water Equations, Eulerian-Lagrangian Method (SWE-ELM), and the Shallow Water Equations Eulerian Method (SWE-EM) and compared for both accuracy and computational resources required. In general, the Diffusion Wave Equations results were found to be comparable to the two Shallow Water equations sets while requiring less computational power. The 1D/2D combined approach was valid for study areas within the 2D flow area, with the 1D flow serving mainly as an inflow boundary condition. Within the Delaware Bay estuary, the HEC-RAS DW model ran in 22 minutes and had an average R² value of 0.94 within the 2-D mesh. The Galveston Bay HEC-RAS DW ran in 6 hours and 47 minutes and had an average R² value of 0.83 within the 2-D mesh. The longer run time and lower R² for Galveston Bay can be attributed to the increased length of the time frame modeled and the greater complexity of the estuarine system. The models did not accurately capture tidal effects within the 1D flow area.Keywords: Delaware bay, estuarine hydraulics, Galveston bay, HEC-RAS, one-dimensional modeling, two-dimensional modeling
Procedia PDF Downloads 1996926 Land Degradation Assessment through Spatial Data Integration in Eastern Chotanagpur Plateau, India
Authors: Avijit Mahala
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Present study is primarily concerned with the physical processes and status of land degradation in a tropical plateau fringe. Chotanagpur plateau is one of the most water erosion related degraded areas of India. The granite gneiss geological formation, low to medium developed soil cover, undulating lateritic uplands, high drainage density, low to medium rainfall (100-140cm), dry tropical deciduous forest cover makes the Silabati River basin a truly representative of the tropical environment. The different physical factors have been taken for land degradation study includes- physiographic formations, hydrologic characteristics, and vegetation cover. Water erosion, vegetal degradation, soil quality decline are the major processes of land degradation in study area. Granite-gneiss geological formation is responsible for developing undulating landforms. Less developed soil profile, low organic matter, poor structure of soil causes high soil erosion. High relief and sloppy areas cause unstable environment. The dissected highland causes topographic hindrance in productivity. High drainage density and frequency in rugged upland and intense erosion in sloppy areas causes high soil erosion of the basin. Decreasing rainfall and increasing aridity (low P/PET) threats water stress condition. Green biomass cover area is also continuously declining. Through overlaying the different physical factors (geological formation, soil characteristics, geomorphological characteristics, etc.) of considerable importance in GIS environment the varying intensities of land degradation areas has been identified. Middle reaches of Silabati basin with highly eroded laterite soil cover areas are more prone to land degradation.Keywords: land degradation, tropical environment, lateritic upland, undulating landform, aridity, GIS environment
Procedia PDF Downloads 1356925 The Post-Crisis Expansion of European Central Bank Powers: Understanding the Legitimate Boundaries of the ECB's Supervisory Independence and Accountability
Authors: Jakub Gren
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The recent transfer of banking supervision to the ECB has expanded its influence as of a non-majoritarian and technocratic policy-shaper in EU supervisory policies. To fulfil the main policy objectives of the Single Supervisory Mechanism, the ECB has been tasked with building a single supervisory approach to supervised banks across the euro area and is now exclusively responsible for direct supervision of the largest ‘significant’ euro area banks and the oversight of the remaining ‘less significant’ banks. This enhanced supranational position of the ECB significantly alters the EU institutional order and creates powerful incentives to actively pursue integrationist agenda by the ECB. However, this drastic shift has a little impact upon adapting the ECB’s new supervisory mandate to the requirements of democratic legitimacy. Whereas the ECB’s strong pre-crisis independence and limited accountability could be reconciled with democratic principles through a clearly articulated price stability mandate, independence and limited accountability in the context of a more complex supervisory mandate is problematic. Hence, in order to ensure the democratic legitimacy of the ECB/SSM’s supervisory policies, the ECB’s supervisory mandate requires both a lower scope of independence and higher accountability requirements. To address this situation, organizational separation (“Chinese Wall”) between the ECB monetary and supervisory arms was introduced. This separation includes different reporting lines and the relocation of the ECB’s monetary function to a new building complex while leaving its supervisory function at the Euro-tower (“Two Towers”). This paper argues that these measures are not sufficient to establish proper checks and balances on the ECB’s powers to pursue euro zone’s wide supervisory policies. As a remedy, this contribution suggests that the ECB’s Treaties-embedded independence, as set out by art. 130 TFEU, designed to carry out its monetary function shall not be fully applicable to its supervisory function. Indeed functional and conditional reading of this provision to ECB supervisory function could enhance the legitimacy of future ECB’s supervisory action.Keywords: accountability and transparency, democratic governance, financial management, rule of law
Procedia PDF Downloads 2076924 Public Attitudes toward Domestic Violence against Women in China and Spain: A Cross-Cultural Study
Authors: Menglu Yang, Ani Beybutyan, Rocio Pina, Miguel Angel Soria
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Domestic violence against women is one of the most serious social problems in the world. Attitudes toward domestic violence against women play an important role in the perpetration of violence against women, the way that victims respond to the violence, and how the community responds to violence against women. China and Spain are countries which have been influenced by the culture which males hold power and dominance over the female for a long time. However, as more connected with other European countries, the legal enforcement related to domestic violence against women developed earlier in Spain, and consequently, social awareness of violence against women evolved differently in two countries. The present study aimed to explore and compare the attitudes toward domestic violence against women across China and Spain, and their influence factors, such as gender equality attitudes and coercive control. Totally 506 participants, 255 from China and 251 from Spain completed questionnaires, including attitudes toward domestic violence against women, definition of violence behavior, justification for violence, gender equity attitudes, and coercive control. Results demonstrated that Chinese participants were less aware of domestic violence against women issue but more agreed that such issue was a crime than Spanish participants. In addition to cultural difference, gender equality attitudes, coercive control, gender, and age also affected attitudes toward domestic violence against women. Our findings imply attitudes toward domestic violence against women differ from countries along with the difference in gender equity attitudes and coercive control; such a difference may arise from cultural, traditional belief and current justice system influence. Despite the developed justice system, male dominance culture may lead to maintain the belief that domestic violence is domestic and private issue which police and justice force may not get involved.Keywords: cross-cultural differences, domestic violence, public attitudes, violence against women
Procedia PDF Downloads 2766923 Perceptions and Experiences of Learners on the Banning of Corporal Punishment in South African Schools
Authors: Londeka Ngubane
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The use of corporal punishment is not a new phenomenon in the South African education system as it was, for a long time, recognised as a fitting form of punishment for ill-disciplined and disobedient children. The growing recognition that corporal punishment is an act of violence against children has resulted in the abolishment of this form of punishment in society and particularly in schools. However, regardless of criminalising corporal punishment, it appears to be a disciplinary measure that is persistently used by some educators. Historically and currently, the intimate connection between corporal punishment and discipline has not merely been a convention of human thinking, as this practice is given recognition in various definitions in dictionaries. ‘To discipline’ is habitually stated to mean ‘to punish’. The notion of ‘disciplining children’ also comes from entrenched common conceptions about children and their relationship with adults. Corporal punishment has, for a long time, been associated with the rearing and education of children, and this practice thus pervades schooling across nations. In many societies, punishment is a term that is closely linked with the self-perception of teachers who feel that they must be ‘in control’ and have ‘the upper hand’ in order to be respected. This impression of control is evident in the widespread conception of education which is to ‘socialize’ children in ‘desirable ways’ of ‘sitting in a formal classroom’, ‘behaving’ in school, ‘following instructions’ from the teacher, talking only when asked to, and finishing tasks on time. It was against this backdrop that a comprehensive review of relevant literature was undertaken and that individual interviews were conducted with fifty learners from four schools (two junior secondary and two senior secondary schools) in a selected township area in KwaZulu-Natal Province. The main aim of the study was to explore and thus understand learners’ views on the administration of corporal punishment regardless of the fact that it was legally abolished. It was envisaged that the interviews with the learners would elicit rich data that would enhance the researcher’s insight into their perceptions of the persistent use of corporal punishment as a disciplinary measure in their schools. The study was thus premised on the assumption, which had been strengthened by anecdotal and media evidence, that corporal punishment was still administered in some schools in South Africa and in schools in the study area in particular.Keywords: corporal punishment, ban, school learners, South Africa
Procedia PDF Downloads 1566922 Comparative Parametric Analysis on the Dynamic Response of Fibre Composite Beams with Debonding
Authors: Indunil Jayatilake, Warna Karunasena
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Fiber Reinforced Polymer (FRP) composites enjoy an array of applications ranging from aerospace, marine and military to automobile, recreational and civil industry due to their outstanding properties. A structural glass fiber reinforced polymer (GFRP) composite sandwich panel made from E-glass fiber skin and a modified phenolic core has been manufactured in Australia for civil engineering applications. One of the major mechanisms of damage in FRP composites is skin-core debonding. The presence of debonding is of great concern not only because it severely affects the strength but also it modifies the dynamic characteristics of the structure, including natural frequency and vibration modes. This paper deals with the investigation of the dynamic characteristics of a GFRP beam with single and multiple debonding by finite element based numerical simulations and analyses using the STRAND7 finite element (FE) software package. Three-dimensional computer models have been developed and numerical simulations were done to assess the dynamic behavior. The FE model developed has been validated with published experimental, analytical and numerical results for fully bonded as well as debonded beams. A comparative analysis is carried out based on a comprehensive parametric investigation. It is observed that the reduction in natural frequency is more affected by single debonding than the equally sized multiple debonding regions located symmetrically to the single debonding position. Thus it is revealed that a large single debonding area leads to more damage in terms of natural frequency reduction than isolated small debonding zones of equivalent area, appearing in the GFRP beam. Furthermore, the extents of natural frequency shifts seem mode-dependent and do not seem to have a monotonous trend of increasing with the mode numbers.Keywords: debonding, dynamic response, finite element modelling, novel FRP beams
Procedia PDF Downloads 1176921 Performance of AquaCrop Model for Simulating Maize Growth and Yield Under Varying Sowing Dates in Shire Area, North Ethiopia
Authors: Teklay Tesfay, Gebreyesus Brhane Tesfahunegn, Abadi Berhane, Selemawit Girmay
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Adjusting the proper sowing date of a crop at a particular location with a changing climate is an essential management option to maximize crop yield. However, determining the optimum sowing date for rainfed maize production through field experimentation requires repeated trials for many years in different weather conditions and crop management. To avoid such long-term experimentation to determine the optimum sowing date, crop models such as AquaCrop are useful. Therefore, the overall objective of this study was to evaluate the performance of AquaCrop model in simulating maize productivity under varying sowing dates. A field experiment was conducted for two consecutive cropping seasons by deploying four maize seed sowing dates in a randomized complete block design with three replications. Input data required to run this model are stored as climate, crop, soil, and management files in the AquaCrop database and adjusted through the user interface. Observed data from separate field experiments was used to calibrate and validate the model. AquaCrop model was validated for its performance in simulating the green canopy and aboveground biomass of maize for the varying sowing dates based on the calibrated parameters. Results of the present study showed that there was a good agreement (an overall R2 =, Ef= d= RMSE =) between measured and simulated values of the canopy cover and biomass yields. Considering the overall values of the statistical test indicators, the performance of the model to predict maize growth and biomass yield was successful, and so this is a valuable tool help for decision-making. Hence, this calibrated and validated model is suggested to use for determining optimum maize crop sowing date for similar climate and soil conditions to the study area, instead of conducting long-term experimentation.Keywords: AquaCrop model, calibration, validation, simulation
Procedia PDF Downloads 716920 Sustainable Happiness of Thai People: Monitoring the Thai Happiness Index
Authors: Kalayanee Senasu
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This research investigates the influences of different factors on the happiness of Thai people, including both general factors and sustainable ones. Additionally, this study also monitors Thai people’s happiness via Thai Happiness Index developed in 2017. Besides reflecting happiness level of Thai people, this index also identifies related important issues. The data were collected by both secondary related data and primary survey data collected by interviewed questionnaires. The research data were from stratified multi-stage sampling in region, province, district, and enumeration area, and simple random sampling in each enumeration area. The research data cover 20 provinces, including Bangkok and 4-5 provinces in each region of the North, Northeastern, Central, and South. There were 4,960 usable respondents who were at least 15 years old. Statistical analyses included both descriptive and inferential statistics, including hierarchical regression and one-way ANOVA. The Alkire and Foster method was adopted to develop and calculate the Thai happiness index. The results reveal that the quality of household economy plays the most important role in predicting happiness. The results also indicate that quality of family, quality of health, and effectiveness of public administration in the provincial level have positive effects on happiness at about similar levels. For the socio-economic factors, the results reveal that age, education level, and household revenue have significant effects on happiness. For computing Thai happiness index (THaI), the result reveals the 2018 THaI value is 0.556. When people are divided into four groups depending upon their degree of happiness, it is found that a total of 21.1% of population are happy, with 6.0% called deeply happy and 15.1% called extensively happy. A total of 78.9% of population are not-yet-happy, with 31.8% called narrowly happy, and 47.1% called unhappy. A group of happy population reflects the happiness index THaI valued of 0.789, which is much higher than the THaI valued of 0.494 of the not-yet-happy population. Overall Thai people have higher happiness compared to 2017 when the happiness index was 0.506.Keywords: happiness, quality of life, sustainability, Thai Happiness Index
Procedia PDF Downloads 1686919 Assessing the Impact of Quinoa Cultivation Adopted to Produce a Secure Food Crop and Poverty Reduction by Farmers in Rural Pakistan
Authors: Ejaz Ashraf, Raheel Babar, Muhammad Yaseen, Hafiz Khurram Shurjeel, Nosheen Fatima
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Main purpose of this study was to assess adoption level of farmers for quinoa cultivation after they had been taught through training and visit extension approach. At this time of the 21st century, population structure, climate change, food requirements and eating habits of people are changing rapidly. In this scenario, farmers must play their key role in sustainable crop development and production through adoption of new crops that may also be helpful to overcome the issue of food insecurity as well as reducing poverty in rural areas. Its cultivation in Pakistan is at the early stages and there is a need to raise awareness among farmers to grow quinoa crops. In the middle of the 2015, a training and visit extension approach was used to raise awareness and convince farmers to grow quinoa in the area. During training and visit extension program, 80 farmers were randomly selected for the training of quinoa cultivation. Later on, these farmers trained 60 more farmers living into their neighborhood. After six months, a survey was conducted with all 140 farmers to assess the impact of the training and visit program on adoption level of respondents for the quinoa crop. The survey instrument was developed with the help of literature review and other experts of the crop. Validity and reliability of the instrument were checked before complete data collection. The data were analyzed by using SPSS. Multiple regression analysis was used for interpretation of the results from the survey, which indicated that factors like information/ training, change in agronomic and plant protection practices play a key role in the adoption of quinoa cultivation by respondents. In addition, the model explains more than 50% of variation in the adoption level of respondents. It is concluded that farmers need timely information for improved knowledge of agronomic and plant protection practices to adopt cultivation of the quinoa crop in the area.Keywords: farmers, quinoa, adoption, contact, training and visit
Procedia PDF Downloads 3576918 Assessing the Plant Diversity's Quality, Threats and Opportunities for the Support of Sustainable City Development of the City Raipur, India
Authors: Katharina Lapin, Debashis Sanyal
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Worldwide urban areas are growing. Urbanization has a great impact on social and economic development and ecosystem services. This global trend of urbanization also has significant impact on habitat and biodiversity. The impact of urbanization on the biodiversity of cities in Europe and North America is well studied, while there is a lack of data from cities in currently fast growing urban areas. Indian cities are expanding. The scientific community and the governmental authorities are facing the ongoing urbanization process as an opportunity for the environment. This case study supports the evaluation of urban biodiversity of the city Raipur in the North-West of India. The aim of this study is to assess the overview of the environmental and ecological implications of urbanization. The collected data and analysis was used to discuss the challenges for the sustainable city development. Vascular plants were chosen as an appropriate indicator for the assessment of local biodiversity changes. On the one hand, the vegetation cover is sensible to anthropogenic influence, and in the other hand, the local species composition is comparable to changes at the regional and national scale, using the plant index of India. Further information of abiotic situation can be gathered with the determination of indicator species. In order to calculate the influence of urbanization on the native plant diversity, the Shannon diversity index H´ was chosen. The Pielou`s pooled quadrate method was used for estimating diversity when a random sample is not expected. It was used to calculate the Pilou´s index of evenness. The estimated species coverage was used for calculating the H´ and J. Pearson correlation was performed to test the relationship between urbanization pattern and plant diversity. Further, a SWOT analysis was used in for analyzing internal and external factors impinging on a decision making process. The city of Raipur (21.25°N 81.63°E) has a population of 1,010,087 inhabitants living in an urban area of 226km², in the district of the Indian state of Chhattisgarh. Within the last decade, the urban area of Raipur increased. The results show that various novel ecosystems exist in the urban area of Raipur. The high amount of native flora is mainly to find at the shore of urban lakes and along the river Karun. These areas of high Biodiversity Index are to protect as urban biodiversity hot spots. The governmental authorities are well informed about the environmental challenges for the sustainable development of the city. Together with the scientific community of the Technical University of Raipur many engineering solutions are discussed for implementation of the future. The case study helped to point out the importance environmental measures that support the ecosystem services of green infrastructure. The fast process of urbanization is difficult to control. Uncontrolled creation of urban housing leads to difficulties in unsustainable use of natural resources. This is the major threat for the urban biodiversity.Keywords: India, novel ecosystems, plant diversity, urban ecology
Procedia PDF Downloads 2776917 Territory and Well-Being: Qualitative Insights from the Morvan (Burgandy, France)
Authors: Gaël Brulé
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The concept of territory seems to be largely absent from the literature on well-being. In the present study, the link between the territory and well-being is analyzed in the context of a rural area, the Morvan, in Burgundy (France). Through qualitative research-mostly interviews- this link is questioned and explored. The relationship between the territory and the actors inform us on several key-concepts often related to well-being: locus of control, mobility and identity. From an interactionist perspective, the relation between territory and actors seems to be a fertile ground to explore the latters’ well-being. The present paper advocates for more research on the field.Keywords: territory, well-being, identity, mobility
Procedia PDF Downloads 3096916 Rapid Monitoring of Earthquake Damages Using Optical and SAR Data
Authors: Saeid Gharechelou, Ryutaro Tateishi
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Earthquake is an inevitable catastrophic natural disaster. The damages of buildings and man-made structures, where most of the human activities occur are the major cause of casualties from earthquakes. A comparison of optical and SAR data is presented in the case of Kathmandu valley which was hardly shaken by 2015-Nepal Earthquake. Though many existing researchers have conducted optical data based estimated or suggested combined use of optical and SAR data for improved accuracy, however finding cloud-free optical images when urgently needed are not assured. Therefore, this research is specializd in developing SAR based technique with the target of rapid and accurate geospatial reporting. Should considers that limited time available in post-disaster situation offering quick computation exclusively based on two pairs of pre-seismic and co-seismic single look complex (SLC) images. The InSAR coherence pre-seismic, co-seismic and post-seismic was used to detect the change in damaged area. In addition, the ground truth data from field applied to optical data by random forest classification for detection of damaged area. The ground truth data collected in the field were used to assess the accuracy of supervised classification approach. Though a higher accuracy obtained from the optical data then integration by optical-SAR data. Limitation of cloud-free images when urgently needed for earthquak evevent are and is not assured, thus further research on improving the SAR based damage detection is suggested. Availability of very accurate damage information is expected for channelling the rescue and emergency operations. It is expected that the quick reporting of the post-disaster damage situation quantified by the rapid earthquake assessment should assist in channeling the rescue and emergency operations, and in informing the public about the scale of damage.Keywords: Sentinel-1A data, Landsat-8, earthquake damage, InSAR, rapid damage monitoring, 2015-Nepal earthquake
Procedia PDF Downloads 1726915 Experimental Investigation of Nucleate Pool Boiling Heat Transfer on Laser-Structured Copper Surfaces of Different Patterns
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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With reference to Energy Roadmap 2050, the minimization of greenhouse gas emissions and the enhancement of energy efficiency are the two key factors that could facilitate a radical change in the world's energy infrastructure. However, the energy demands of electronic devices skyrocketed with the advent of the digital age. 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 finding 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-structured 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-structured copper surfaces is superior to the bare copper surface in all aspects.Keywords: heat transfer coefficient, laser structuring, micro structured surface, pool boiling
Procedia PDF Downloads 836914 Experimental Investigation of Nucleate Pool Boiling Heat Transfer on Laser-Structured Copper Surfaces of Different Patterns
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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With reference to Energy Roadmap 2050, the minimization of greenhouse gas emissions, and the enhancement of energy efficiency are the two key factors that could facilitate a radical change in the world's energy infrastructure. However, the energy demands of electronic devices skyrocketed with the advent of the digital age. 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-structured 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-structured copper surfaces is superior to the bare copper surface in all aspects.Keywords: heat transfer coefficient, laser structuring, micro structured surface, pool boiling
Procedia PDF Downloads 816913 Experimental Investigation of Nucleate Pool Boiling Heat Transfer on Laser-Structured Copper Surfaces of Different Patterns
Authors: Luvindran Sugumaran, Mohd Nashrul Mohd Zubir, Kazi Md. Salim Newaz, Tuan Zaharinie Tuan Zahari, Suazlan Mt Aznam, Aiman Mohd Halil
Abstract:
With reference to Energy Roadmap 2050, the minimization of greenhouse gas emissions and the enhancement of energy efficiency are the two key factors that could facilitate a radical change in the world's energy infrastructure. However, the energy demands of electronic devices skyrocketed with the advent of the digital age. 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-structured 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-structured copper surfaces is superior to the bare copper surface in all aspects.Keywords: heat transfer coefficient, laser structuring, micro structured surface, pool boiling
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