Search results for: 3-D numerical investigation
1586 Sustainable Accommodation Design: Improving Residential Property Shortage for Low-Income People in Nigeria
Authors: Paulinus W. Ihuah, Iyenemi Ibimina Kakulu, Victor A. Akujuru
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The development of the residential property is very expensive in Nigeria, especially as it is observed in Port Harcourt, although it is also investment costly in the other cities of Nigeria. The costly development nature incidentally reasons to the high deficits in residential property availability and affordability for the low-income people. Therefore, the main purpose of this paper is to provide sustainable accommodation design, which should improve residential property expensiveness and shortages for the low-income people. This is achieved through investigation of the tangible requirements and needs of the end-user of the property (low-income people), which thereafter would enhance sustainable and affordable residential property accommodation design for the end-users. Both the quantitative and qualitative instruments of data collection were utilised. The quantitative instrument via questionnaires was designed to examine the real needs and r requirement of the low-income people. However, the qualitative instrument via structured interview was espoused for the gathering of professionals’ opinions on the three predicted sustainable accommodation design alternatives. The analysis employed content analysis parameters, which offered a sustainable accommodation design and designed alternatives minimises costs and environmental impacts whereas exploiting the social satisfaction in residential accommodation developments. The finding underscores that sustainable accommodation design and development is practicable in Nigeria, so that cost of residential accommodation provided through this system is cheap to the low-income people. Further, erection of multi-storey residential accommodation units such as bedsit structure by utilising the concrete frame structure and building the internal and external walls with hollow concrete blocks within areas 60-130 square meters is encouraged. This paper philosophy indicates that by using sustainable accommodation design practices in Nigeria, improvements in the costs and shortages of residential accommodation can be attained for low-income people. However, policies support the government cannot be overemphasised for proper implementation of the suggested scheme.Keywords: sustainable accommodation, housing design, residential property, low-income people
Procedia PDF Downloads 2701585 Development of a Paediatric Head Model for the Computational Analysis of Head Impact Interactions
Authors: G. A. Khalid, M. D. Jones, R. Prabhu, A. Mason-Jones, W. Whittington, H. Bakhtiarydavijani, P. S. Theobald
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Head injury in childhood is a common cause of death or permanent disability from injury. However, despite its frequency and significance, there is little understanding of how a child’s head responds during injurious loading. Whilst Infant Post Mortem Human Subject (PMHS) experimentation is a logical approach to understand injury biomechanics, it is the authors’ opinion that a lack of subject availability is hindering potential progress. Computer modelling adds great value when considering adult populations; however, its potential remains largely untapped for infant surrogates. The complexities of child growth and development, which result in age dependent changes in anatomy, geometry and physical response characteristics, present new challenges for computational simulation. Further geometric challenges are presented by the intricate infant cranial bones, which are separated by sutures and fontanelles and demonstrate a visible fibre orientation. This study presents an FE model of a newborn infant’s head, developed from high-resolution computer tomography scans, informed by published tissue material properties. To mimic the fibre orientation of immature cranial bone, anisotropic properties were applied to the FE cranial bone model, with elastic moduli representing the bone response both parallel and perpendicular to the fibre orientation. Biofiedility of the computational model was confirmed by global validation against published PMHS data, by replicating experimental impact tests with a series of computational simulations, in terms of head kinematic responses. Numerical results confirm that the FE head model’s mechanical response is in favourable agreement with the PMHS drop test results.Keywords: finite element analysis, impact simulation, infant head trauma, material properties, post mortem human subjects
Procedia PDF Downloads 3261584 Finite Element Modeling and Nonlinear Analysis for Seismic Assessment of Off-Diagonal Steel Braced RC Frame
Authors: Keyvan Ramin
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The geometric nonlinearity of Off-Diagonal Bracing System (ODBS) could be a complementary system to covering and extending the nonlinearity of reinforced concrete material. Finite element modeling is performed for flexural frame, x-braced frame and the ODBS braced frame system at the initial phase. Then the different models are investigated along various analyses. According to the experimental results of flexural and x-braced frame, the verification is done. Analytical assessments are performed in according to three-dimensional finite element modeling. Non-linear static analysis is considered to obtain performance level and seismic behavior, and then the response modification factors calculated from each model’s pushover curve. In the next phase, the evaluation of cracks observed in the finite element models, especially for RC members of all three systems is performed. The finite element assessment is performed on engendered cracks in ODBS braced frame for various time steps. The nonlinear dynamic time history analysis accomplished in different stories models for three records of Elcentro, Naghan, and Tabas earthquake accelerograms. Dynamic analysis is performed after scaling accelerogram on each type of flexural frame, x-braced frame and ODBS braced frame one by one. The base-point on RC frame is considered to investigate proportional displacement under each record. Hysteresis curves are assessed along continuing this study. The equivalent viscous damping for ODBS system is estimated in according to references. Results in each section show the ODBS system has an acceptable seismic behavior and their conclusions have been converged when the ODBS system is utilized in reinforced concrete frame.Keywords: FEM, seismic behaviour, pushover analysis, geometric nonlinearity, time history analysis, equivalent viscous damping, passive control, crack investigation, hysteresis curve
Procedia PDF Downloads 3781583 Understanding the Factors behind Graduate Employability in the United Arab Emirates
Authors: Mohammed Islam
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Graduate employability is a well debated topic by governments, employers, and higher education institutes (HEI) across the world. Much of the focus of these debates have centred around the skills that graduates bring or should bring to the job market, a point echoed by United Arab Emirates (UAE) policy makers and employers. While some research has been carried out on graduates' employability skills, little or no attention has been paid to the forces at play in developing employability policy and its subsequent implementation. The focus of debate has been on a perceived skills gap rather than policy. Recognising a gap in the literature, this paper details a study of UAE employability policy development. Taking a social constructionist approach, this case study views policy as discursive and socially constructed through interactions with key stakeholders. It is within the myriad of interdependent socio-political factors and social practices, particularly power relationships, that this paper explores UAE policy on graduate employability. In doing so, this adds to the debate on graduate employability from the perspective of policy and explores its roots in the interaction between human activity and the ‘system’. Data was collected from two main sources: documentary review and semi-structured interviews. Policies and publicly stated rhetoric on graduate employability were analysed using Critical Discourse Analysis. Semi-structured interviews with representatives from policy makers, HEIs, and employers were reviewed through Thematic Analysis. The theoretical framework for the discussion of findings draws from social practice theories and highlights the factors at play in access to employment for UAE graduates. This case study presents a methodological approach to policy studies that can be applied beyond the context under investigation. Education policy researchers are provided with an opportunity to compare similarities and differences with their own specific contexts.Keywords: critical discourse analysis, employability, methodology, policy, social constructionism
Procedia PDF Downloads 1271582 Slope Stability Analysis and Evaluation of Road Cut Slope in Case of Goro to Abagada Road, Adama
Authors: Ezedin Geta Seid
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Slope failures are among the common geo-environmental natural hazards in the hilly and mountainous terrain of the world causing damages to human life and destruction of infrastructures. In Ethiopia, the demand for the construction of infrastructures, especially highways and railways, has increased to connect the developmental centers. However, the failure of roadside slopes formed due to the difficulty of geographical locations is the major difficulty for this development. As a result, a comprehensive site-specific investigation of destabilizing agents and a suitable selection of slope profiles are needed during design. Hence, this study emphasized the stability analysis and performance evaluation of slope profiles (single slope, multi-slope, and benched slope). The analysis was conducted for static and dynamic loading conditions using limit equilibrium (slide software) and finite element method (Praxis software). The analysis results in selected critical sections show that the slope is marginally stable, with FS varying from 1.2 to 1.5 in static conditions, and unstable with FS below 1 in dynamic conditions. From the comparison of analysis methods, the finite element method provides more valuable information about the failure surface of a slope than limit equilibrium analysis. Performance evaluation of geometric profiles shows that geometric modification provides better and more economical slope stability. Benching provides significant stability for cut slopes (i.e., the use of 2m and 3m bench improves the factor of safety by 7.5% and 12% from a single slope profile). The method is more effective on steep slopes. Similarly, the use of a multi-slope profile improves the stability of the slope in stratified soil with varied strength. The performance is more significant when it is used in combination with benches. The study also recommends drainage control and slope reinforcement as a remedial measure for cut slopes.Keywords: slope failure, slope profile, bench slope, multi slope
Procedia PDF Downloads 311581 The Axonal Connectivity of Motor and Premotor Areas as Revealed through Fiber Dissections: Shedding Light on the Structural Correlates of Complex Motor Behavior
Authors: Spyridon Komaitis, Christos Koutsarnakis, Evangelos Drosos, Aristotelis Kalyvas
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This study opts to investigate the intrinsic architecture, morphology, and spatial relationship of the subcortical pathways implicated in the connectivity of the motor/premotor cortex and SMA/pre-SMA complex. Twenty normal, adult, formalin-fixed cerebral hemispheres were explored through the fiber micro-dissection technique. Lateral to medial and medial to lateral dissections focused on the area of interest were performed in a tandem manner and under the surgical microscope. We traced the subcortical architecture, spatial relationships, and axonal connectivity of four major pathways: a) the dorsal component of the SLF (SLF-I) was found to reside in the medial aspect of the hemisphere and seen to connect the precuneus with the SMA and pre-SMA complex, b) the frontal longitudinal system (FLS) was consistently encountered as the natural anterior continuation of the SLF-II and SLF-III and connected the premotor and prefrontal cortices c) the fronto-caudate tract (FCT), a fan-shaped tract, was documented to participate in connectivity of the prefrontal and premotor cortices to the head and body of the caudate nucleus and d) the cortico-tegmental tract(CTT) was invariably recorded to subserve the connectivity of the tegmental area with the fronto-parietal cortex. No hemispheric asymmetries were recorded for any of the implicated pathways. Sub-segmentation systems were also proposed for each of the aforementioned tracts. The structural connectivity and functional specialization of motor and premotor areas in the human brain remain vague to this day as most of the available evidence derives either from animal or tractographic studies. By using the fiber-microdissection technique as our main method of investigation, we provide sound structural evidence on the delicate anatomy of the related white matter pathways.Keywords: neuroanatomy, premotor, motor, connectivity
Procedia PDF Downloads 1281580 Effectiveness of Climate Smart Agriculture in Managing Field Stresses in Robusta Coffee
Authors: Andrew Kirabira
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This study is an investigation into the effectiveness of climate-smart agriculture (CSA) technologies in improving productivity through managing biotic and abiotic stresses in the coffee agroecological zones of Uganda. The motive is to enhance farmer livelihoods. The study was initiated as a result of the decreasing productivity of the crop in Uganda caused by the increasing prevalence of pests, diseases and abiotic stresses. Despite 9 years of farmers’ application of CSA, productivity has stagnated between 700kg -800kg/ha/yr which is only 26% of the 3-5tn/ha/yr that CSA is capable of delivering if properly applied. This has negatively affected the incomes of the 10.6 million people along the crop value chain which has in essence affected the country’s national income. In 2019/20 FY for example, Uganda suffered a deficit of $40m out of singularly the increasing incidence of one pest; BCTB. The amalgamation of such trends cripples the realization of SDG #1 and #13 which are the eradication of poverty and mitigation of climate change, respectively. In probing CSA’s effectiveness in curbing such a trend, this study is guided by the objectives of; determining the existing farmers’ knowledge and perceptions of CSA amongst the coffee farmers in the diverse coffee agro-ecological zones of Uganda; examining the relationship between the use of CSA and prevalence of selected coffee pests, diseases and abiotic stresses; ascertaining the difference in the market organization and pricing between conventionally and CSA produced coffee; and analyzing the prevailing policy environment concerning the use of CSA in coffee production. The data collection research design is descriptive in nature; collecting data from farmers and agricultural extension workers in the districts of Ntungamo, Iganga and Luweero; each of these districts representing a distinct coffee agroecological zone. Policy custodian officers at district, cooperatives and at the crop’s overseeing national authority were also interviewed.Keywords: climate change, food security, field stresses, Productivity
Procedia PDF Downloads 571579 Scientific Investigation for an Ancient Egyptian Polychrome Wooden Stele
Authors: Ahmed Abdrabou, Medhat Abdalla
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The studied stele dates back to Third Intermediate Period (1075-664) B.C in an ancient Egypt. It is made of wood and covered with painted gesso layers. This study aims to use a combination of multi spectral imaging {visible, infrared (IR), Visible-induced infrared luminescence (VIL), Visible-induced ultraviolet luminescence (UVL) and ultraviolet reflected (UVR)}, along with portable x-ray fluorescence in order to map and identify the pigments as well as to provide a deeper understanding of the painting techniques. Moreover; the authors were significantly interested in the identification of wood species. Multispectral imaging acquired in 3 spectral bands, ultraviolet (360-400 nm), visible (400-780 nm) and infrared (780-1100 nm) using (UV Ultraviolet-induced luminescence (UVL), UV Reflected (UVR), Visible (VIS), Visible-induced infrared luminescence (VIL) and Infrared photography. False color images are made by digitally editing the VIS with IR or UV images using Adobe Photoshop. Optical Microscopy (OM), potable X-ray fluorescence spectroscopy (p-XRF) and Fourier Transform Infrared Spectroscopy (FTIR) were used in this study. Mapping and imaging techniques provided useful information about the spatial distribution of pigments, in particular visible-induced luminescence (VIL) which allowed the spatial distribution of Egyptian blue pigment to be mapped and every region containing Egyptian blue, even down to single crystals in some instances, is clearly visible as a bright white area; however complete characterization of the pigments requires the use of p. XRF spectroscopy. Based on the elemental analysis found by P.XRF, we conclude that the artists used mixtures of the basic mineral pigments to achieve a wider palette of hues. Identification of wood species Microscopic identification indicated that the wood used was Sycamore Fig (Ficus sycomorus L.) which is recorded as being native to Egypt and was used to make wooden artifacts since at least the Fifth Dynasty.Keywords: polychrome wooden stele, multispectral imaging, IR luminescence, Wood identification, Sycamore Fig, p-XRF
Procedia PDF Downloads 2641578 Alumina Supported Copper-Manganese-Cobalt Catalysts for CO and VOCs Oxidation
Authors: Elitsa Kolentsova, Dimitar Dimitrov, Vasko Idakiev, Tatyana Tabakova, Krasimir Ivanov
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Formaldehyde production by selective oxidation of methanol is an important industrial process. The main by-products in the waste gas are CO and dimethyl ether (DME). The idea of this study is to combine the advantages of both Cu-Mn and Cu-Co catalytic systems by obtaining a new mixed Cu-Mn-Co catalyst with high activity and selectivity at the simultaneous oxidation of CO, methanol, and DME. Two basic Cu-Mn samples with high activity were selected for further investigation: (i) manganese-rich Cu-Mn/γ–Al2O3 catalyst with Cu/Mn molar ratio 1:5 and (ii) copper-rich Cu-Mn/γ-Al2O3 catalyst with Cu/Mn molar ratio 2:1. Manganese in these samples was replaced by cobalt in the whole concentration region, and catalytic properties were determined. The results show a general trend of decreasing the activity toward DME oxidation and increasing the activity toward CO and methanol oxidation with the increase of cobalt up to 60% for both groups of catalyst. This general trend, however, contains specific features, depending on the composition of the catalyst and the nature of the oxidized gas. The catalytic activity of the sample with Cu/(Mn+Co) molar ratio of 2:1 is gradually changed with increasing the cobalt content. The activity of the sample with Cu/(Mn+Co) molar ratio of 1: 5 passes through a maximum at 60% manganese replacement by cobalt, probably due to the formation of highly dispersed Co-based spinel structures (Co3O4 and/or MnCo2O4). In conclusion, the present study demonstrates that the Cu-Mn-Co/γ–alumina supported catalysts have enhanced activity toward CO, methanol and DME oxidation. Cu/(Mn+Co) molar ratio 1:5 and Co/Mn molar ratio 1.5 in the active component can ensure successful oxidation of CO, CH3OH and DME. The active component of the mixed Cu-Mn-Co/γ–alumina catalysts consists of at least six compounds - CuO, Co3O4, MnO2, Cu1.5Mn1.5O4, MnCo2O4 and CuCo2O4, depending on the Cu/Mn/Co molar ratio. Chemical composition strongly influences catalytic properties, this effect being quite variable with regards to the different processes.Keywords: Cu-Mn-Co catalysts, oxidation, carbon oxide, VOCs
Procedia PDF Downloads 2221577 Zimbabwe's Foreign Policy in Southern Africa, 1980-2013
Authors: Dylan Yanano Mangani, Theodore Nkadimeng Mahosi
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Soon after independence on 18th April 1980, Zimbabwe’s foreign policy was shaped by the realities on the ground, which saw the country managing a sound relationship with both the Capitalist West and the Communist Eastern blocs. The post-independence foreign policy was therefore premised on security concerns illuminated by the Cold War era. This was one the reasons President Robert Mugabe adopted a policy of reconciliation and this earned his government recognition on the international platform. However, in Southern Africa apartheid South Africa was still the vanguard of capitalism and oppression such that she posed a serious threat to the newly born Zimbabwean nation which necessitated that Zimbabwe position herself both in the region and the continent to counter potential internal stability from within. Irrespective of how the international community viewed the country’s foreign policy Zimbabwe has continued to influence regional, continental and world geo-politics, especially on behalf of the developing nations. This raises a question why as a result of its foreign policy the country is now regarded a pariah state, especially some Western countries which used to applaud its political economic policies immediately after independence. Therefore, this study argues that the political economy of Zimbabwe had a far-reaching bearing on its foreign policy. For this reason, the problem necessitates the investigation of Zimbabwe’s foreign policy perspectives in Southern Africa since the turn of the 1990s. Two main theories which are Realism, Afro-centrism inform the study as an attempt to understand Zimbabwe’s foreign policy paradigm shift and perhaps provide answers to the objectives raised. The research therefore employs a qualitative approach where the conceptual nature of the study into the foreign policy of Zimbabwe is largely desktop research. However, the nature of the study will also require that oral interviews are conducted to substantiate some of the arguments advanced.Keywords: cold war set up, foreign policy, look east policy, pan-africanism, post 2000 period, Southern Africa, Zimbabwe
Procedia PDF Downloads 3281576 Development of Essential Oil-Loaded Gelatin Hydrogels for Use as Antibacterial Wound Dressing
Authors: Piyachat Chuysinuan, Nitirat Chimnoi, Arthit Makarasen, Nanthawan Reuk-Ngam, Pitt Supaphol, Supanna Techasakul
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In this work, biomaterial wound dressings was developed based on gelatin containing herbal substances (essential oil), a substance from the plant Eupatorium adenophorum Spreng (Crofton weed) that used as traditional wound healers. Gelatin hydrogel was prepared from a 10 wt-% gelatin solution. The oil in water (o/w) emulsion Eupatorium adenophorum of essential oil were prepared and used Pluronic F68 as a surfactant. The 10, 20, and 30 % v/v emulsion were mixed with gelatin solution and cast into film. These hydrogels were tested for their gel fraction, swelling and weight loss behavior. With an increase in the emulsion concentration the emulsion-loaded in hydrogels, the gel fraction were decreased due to the crosslink density, while the swelling and weight loss behavior were increased with an increasing in the emulsion content. The potential to use the emulsion-containing gelatin hydrogels as wound dressing was assessed on investigation the release characteristics of the as-loaded hydrogels. The E. adenophorum essential oil was first identified the chemical composition by using GC-MS analysis. The principal components of the oil were p-cymene (16.23%), bornyl acetate (11.84%), and amorpha-4, 7(11)-diene (10.51%). The hydrogel wound dressing containing essential oil was then characterized for their antibacterial activity against Gram-positive and Gram-negative in order to elucidate their potential for use as antibacterial wound dressings by using agar disk diffusion methods. The result showed that E. adenophorum essential oil and the emulsion-loaded gelatin hydrogel inhibited the growth of the test pathogens, Staphylococcus aureus and Staphylococcus epidermidis and increased with increasing the initial amount of essential oil in the hydrogels which confirmed their application as antibacterial wound dressings. Furthermore, the potential use of these wound dressings was further assessed in terms of the indirect cytotoxicity, in vitro attachment and proliferation of dermal human fibroblasts cultured in the hydrogel wound dressings.Keywords: hydrogel, antibacterial wound dressing, Eupatorium adenophorum essential oil, gelatin
Procedia PDF Downloads 3561575 Fatty Acid Structure and Composition Effects of Biodiesel on Its Oxidative Stability
Authors: Gelu Varghese, Khizer Saeed
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Biodiesel is as a mixture of mono-alkyl esters of long chain fatty acids derived from vegetable oils or animal fats. Recent studies in the literature suggest that end property of biodiesel such as its oxidative stability (OS) is highly influenced by the structure and composition of its alkyl esters than by environmental conditions. The structure and composition of these long chain fatty acid components have been also associated with trends in Cetane number, heat of combustion, cold flow properties viscosity, and lubricity. In the present work, detailed investigation has been carried out to decouple and correlate the fatty acid structure indices of biodiesel such as degree of unsaturation, chain length, double bond orientation, and composition with its oxidative stability. Measurements were taken using the EN14214 established Rancimat oxidative stability test method (EN141120). Firstly, effects of the degree of unsaturation, chain length and bond orientation were tested for the pure fatty acids to establish their oxidative stability. Results for pure Fatty acid show that Saturated FAs are more stable than unsaturated ones to oxidation; superior oxidative stability can be achieved by blending biodiesel fuels with relatively high in saturated fatty acid contents. A lower oxidative stability is noticed when a greater quantity of double bonds is present in the methyl ester. A strong inverse relationship with the number of double bonds and the Rancimat IP values can be identified. Trans isomer Methyl elaidate shows superior stability to oxidation than its cis isomer methyl oleate (7.2 vs. 2.3). Secondly, the effects of the variation in the composition of the biodiesel were investigated and established. Finally, biodiesels with varying structure and composition were investigated and correlated.Keywords: biodiesel, fame, oxidative stability, fatty acid structure, acid composition
Procedia PDF Downloads 2861574 An Investigation of the Effects of Gripping Systems in Geosynthetic Shear Testing
Authors: Charles Sikwanda
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The use of geosynthetic materials in geotechnical engineering projects has rapidly increased over the past several years. These materials have resulted in improved performance and cost reduction of geotechnical structures as compared to the use of conventional materials. However, working with geosynthetics requires knowledge of interface parameters for design. These parameters are typically determined by the large direct shear device in accordance with ASTM-D5321 and ASTM-D6243 standards. Although these laboratory tests are standardized, the quality of the results can be largely affected by several factors that include; the shearing rate, applied normal stress, gripping mechanism, and type of the geosynthetic specimens tested. Amongst these factors, poor surface gripping of a specimen is the major source of the discrepancy. If the specimen is inadequately secured to the shearing blocks, it experiences progressive failure and shear strength that deviates from the true field performance of the tested material. This leads to inaccurate, unsafe, and cost ineffective designs of projects. Currently, the ASTM-D5321 and ASTM-D6243 standards do not provide a standardized gripping system for geosynthetic shear strength testing. Over the years, researchers have come up with different gripping systems that can be used such as; glue, metal textured surface, sandblasting, and sandpaper. However, these gripping systems are regularly not adequate to sufficiently secure the tested specimens to the shearing device. This has led to large variability in test results and difficulties in results interpretation. Therefore, this study was aimed at determining the effects of gripping systems in geosynthetic interface shear strength testing using a 300 x 300 mm direct shear box. The results of the research will contribute to easy data interpretation and increase result accuracy and reproducibility.Keywords: geosynthetics, shear strength parameters, gripping systems, gripping
Procedia PDF Downloads 2031573 Computer Simulation Approach in the 3D Printing Operations of Surimi Paste
Authors: Timilehin Martins Oyinloye, Won Byong Yoon
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Simulation technology is being adopted in many industries, with research focusing on the development of new ways in which technology becomes embedded within production, services, and society in general. 3D printing (3DP) technology is fast developing in the food industry. However, the limited processability of high-performance material restricts the robustness of the process in some cases. Significantly, the printability of materials becomes the foundation for extrusion-based 3DP, with residual stress being a major challenge in the printing of complex geometry. In many situations, the trial-a-error method is being used to determine the optimum printing condition, which results in time and resource wastage. In this report, the analysis of 3 moisture levels for surimi paste was investigated for an optimum 3DP material and printing conditions by probing its rheology, flow characteristics in the nozzle, and post-deposition process using the finite element method (FEM) model. Rheological tests revealed that surimi pastes with 82% moisture are suitable for 3DP. According to the FEM model, decreasing the nozzle diameter from 1.2 mm to 0.6 mm, increased the die swell from 9.8% to 14.1%. The die swell ratio increased due to an increase in the pressure gradient (1.15107 Pa to 7.80107 Pa) at the nozzle exit. The nozzle diameter influenced the fluid properties, i.e., the shear rate, velocity, and pressure in the flow field, as well as the residual stress and the deformation of the printed sample, according to FEM simulation. The post-printing stability of the model was investigated using the additive layer manufacturing (ALM) model. The ALM simulation revealed that the residual stress and total deformation of the sample were dependent on the nozzle diameter. A small nozzle diameter (0.6 mm) resulted in a greater total deformation (0.023), particularly at the top part of the model, which eventually resulted in the sample collapsing. As the nozzle diameter increased, the accuracy of the model improved until the optimum nozzle size (1.0 mm). Validation with 3D-printed surimi products confirmed that the nozzle diameter was a key parameter affecting the geometry accuracy of 3DP of surimi paste.Keywords: 3D printing, deformation analysis, die swell, numerical simulation, surimi paste
Procedia PDF Downloads 671572 Effect of Halo Protection Device on the Aerodynamic Performance of Formula Racecar
Authors: Mark Lin, Periklis Papadopoulos
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This paper explores the aerodynamics of the formula racecar when a ‘halo’ driver-protection device is added to the chassis. The halo protection device was introduced at the start of the 2018 racing season as a safety measure against foreign object impacts that a driver may encounter when driving an open-wheel racecar. In the one-year since its introduction, the device has received wide acclaim for protecting the driver on two separate occasions. The benefit of such a safety device certainly cannot be disputed. However, by adding the halo device to a car, it changes the airflow around the vehicle, and most notably, to the engine air-intake and the rear wing. These negative effects in the air supply to the engine, and equally to the downforce created by the rear wing are studied in this paper using numerical technique, and the resulting CFD outputs are presented and discussed. Comparing racecar design prior to and after the introduction of the halo device, it is shown that the design of the air intake and the rear wing has not followed suit since the addition of the halo device. The reduction of engine intake mass flow due to the halo device is computed and presented for various speeds the car may be going. Because of the location of the halo device in relation to the air intake, airflow is directed away from the engine, making the engine perform less than optimal. The reduction is quantified in this paper to show the correspondence to reduce the engine output when compared to a similar car without the halo device. This paper shows that through aerodynamic arguments, the engine in a halo car will not receive unobstructed, clean airflow that a non-halo car does. Another negative effect is on the downforce created by the rear wing. Because the amount of downforce created by the rear wing is influenced by every component that comes before it, when a halo device is added upstream to the rear wing, airflow is obstructed, and less is available for making downforce. This reduction in downforce is especially dramatic as the speed is increased. This paper presents a graph of downforce over a range of speeds for a car with and without the halo device. Acknowledging that although driver safety is paramount, the negative effect of this safety device on the performance of the car should still be well understood so that any possible redesign to mitigate these negative effects can be taken into account in next year’s rules regulation.Keywords: automotive aerodynamics, halo device, downforce. engine intake
Procedia PDF Downloads 1101571 Testing and Validation Stochastic Models in Epidemiology
Authors: Snigdha Sahai, Devaki Chikkavenkatappa Yellappa
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This study outlines approaches for testing and validating stochastic models used in epidemiology, focusing on the integration and functional testing of simulation code. It details methods for combining simple functions into comprehensive simulations, distinguishing between deterministic and stochastic components, and applying tests to ensure robustness. Techniques include isolating stochastic elements, utilizing large sample sizes for validation, and handling special cases. Practical examples are provided using R code to demonstrate integration testing, handling of incorrect inputs, and special cases. The study emphasizes the importance of both functional and defensive programming to enhance code reliability and user-friendliness.Keywords: computational epidemiology, epidemiology, public health, infectious disease modeling, statistical analysis, health data analysis, disease transmission dynamics, predictive modeling in health, population health modeling, quantitative public health, random sampling simulations, randomized numerical analysis, simulation-based analysis, variance-based simulations, algorithmic disease simulation, computational public health strategies, epidemiological surveillance, disease pattern analysis, epidemic risk assessment, population-based health strategies, preventive healthcare models, infection dynamics in populations, contagion spread prediction models, survival analysis techniques, epidemiological data mining, host-pathogen interaction models, risk assessment algorithms for disease spread, decision-support systems in epidemiology, macro-level health impact simulations, socioeconomic determinants in disease spread, data-driven decision making in public health, quantitative impact assessment of health policies, biostatistical methods in population health, probability-driven health outcome predictions
Procedia PDF Downloads 61570 An Audit on the Quality of Pre-Operative Intra-Oral Digital Radiographs Taken for Dental Extractions in a General Practice Setting
Authors: Gabrielle O'Donoghue
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Background: Pre-operative radiographs facilitate assessment and treatment planning in minor oral surgery. Quality assurance for dental radiography advocates the As Low As Reasonably Achievable (ALARA) principle in collecting accurate diagnostic information. Aims: To audit the quality of digital intraoral periapicals (IOPAs) taken prior to dental extractions in a metropolitan general dental practice setting. Standards: The National Radiological Protection Board (NRPB) guidance outlines three grades of radiograph quality: excellent (Grade 1 > 70% of total exposures), diagnostically acceptable (Grade 2 <20%), and unacceptable (Grade 3 <10%). Methodology: A study of pre-operative radiographs taken prior to dental extractions across 12 private general dental practices in a large metropolitan area by 44 practitioners. A total of 725 extractions were assessed, allowing 258 IOPAs to be reviewed in one audit cycle. Results: First cycle: Of 258 IOPAs: 223(86.4%) scored Grade 1, 27(10.5%) Grade 2, and 8(3.1%) Grade 3. The standard was met. 35 dental extractions were performed without an available pre-operative radiograph. Action Plan & Recommendations: Results were distributed to all staff and a continuous professional development evening organized to outline recommendations to improve image quality. A second audit cycle is proposed at a six-month interval to review the recommendations and appraise results. Conclusion: The overall standard of radiographs met the published guidelines. A significant improvement in the number of procedures undertaken without pre-operative imaging is expected at a six-month interval period. An investigation into undiagnostic imaging and associated adverse patient outcomes is being considered. Maintenance of the standards achieved is predicted in the second audit cycle to ensure consistent high quality imaging.Keywords: audit, oral radiology, oral surgery, periapical radiographs, quality assurance
Procedia PDF Downloads 1661569 Mental Contrasting with Implementation Intentions: A Metacognitive Strategy on Educational Context
Authors: Paula Paulino, Alzira Matias, Ana Margarida Veiga Simão
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Self-regulated learning (SRL) directs students in analyzing proposed tasks, setting goals and designing plans to achieve those goals. The literature has suggested a metacognitive strategy for goal attainment known as Mental Contrasting with Implementation Intentions (MCII). This strategy involves Mental Contrasting (MC), in which a significant goal and an obstacle are identified, and Implementation Intentions (II), in which an "if... then…" plan is conceived and operationalized to overcome that obstacle. The present study proposes to assess the MCII process and whether it promotes students’ commitment towards learning goals during school tasks in sciences subjects. In this investigation, we intended to study the MCII strategy in a systemic context of the classroom. Fifty-six students from middle school and secondary education attending a public school in Lisbon (Portugal) participated in the study. The MCII strategy was explicitly taught in a procedure that included metacognitive modeling, guided practice and autonomous practice of strategy. A mental contrast between a goal they wanted to achieve and a possible obstacle to achieving that desire was instructed, and then the formulation of plans in order to overcome the obstacle identified previously. The preliminary results suggest that the MCII metacognitive strategy, applied to the school context, leads to more sophisticated reflections, the promotion of learning goals and the elaboration of more complex and specific self-regulated plans. Further, students achieve better results on school tests and worksheets after strategy practice. This study presents important implications since the MCII has been related to improved outcomes and increased attendance. Additionally, MCII seems to be an innovative process that captures students’ efforts to learn and enhances self-efficacy beliefs during learning tasks.Keywords: implementation intentions, learning goals, mental contrasting, metacognitive strategy, self-regulated learning
Procedia PDF Downloads 2411568 Study of Lamination Quality of Semi-Flexible Solar Modules with Special Textile Materials
Authors: K. Drabczyk, Z. Starowicz, S. Maleczek, P. Zieba
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The army, police and fire brigade commonly use dedicated equipment based on special textile materials. The properties of these textiles should ensure human life and health protection. Equally important is the ability to use electronic equipment and this requires access to the source of electricity. Photovoltaic cells integrated with such textiles can be solution for this problem in the most of outdoor circumstances. One idea may be to laminate the cells to textile without changing their properties. The main goal of this work was analyzed lamination quality of special designed semi-flexible solar module with special textile materials as a backsheet. In the first step of investigation, the quality of lamination was determined using device equipped with dynamometer. In this work, the crystalline silicon solar cells 50 x 50 mm and thin chemical tempered glass - 62 x 62 mm and 0.8 mm thick - were used. The obtained results showed the correlation between breaking force and type of textile weave and fiber. The breaking force was in the ranges: 4.5-5.5 N, 15-20 N and 30-33 N depending on the type of wave and fiber type. To verify these observations the microscopic and FTIR analysis of fibers was performed. The studies showed the special textile can be used as a backsheet of semi-flexible solar modules. This work presents a new composition of solar module with special textile layer which, to our best knowledge, has not been published so far. Moreover, the work presents original investigations on adhesion of EVA (ethylene-vinyl acetate) polymer to textile with respect to fiber structure of laminated substrate. This work is realized for the GEKON project (No. GEKON2/O4/268473/23/2016) sponsored by The National Centre for Research and Development and The National Fund for Environmental Protection and Water Management.Keywords: flexible solar modules, lamination process, solar cells, textile for photovoltaics
Procedia PDF Downloads 3581567 Analyzing Oil Seeps Manifestations and Petroleum Impregnation in Northwestern Tunisia From Aliphatic Biomarkers and Statistical Data
Authors: Sawsen Jarray, Tahani Hallek, Mabrouk Montacer
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The tectonically damaged terrain in Tunisia's Northwest is seen in the country's numerous oil leaks. Finding a genetic link between these oil seeps and the area's putative source rocks is the goal of this investigation. Here, we use aliphatic biomarkers assessed by GC-MS to describe the organic geochemical data of 18 oil seeps samples and 4 source rocks (M'Cherga, Fahdene, Bahloul, and BouDabbous). In order to establish correlations between oil and oil and oil and source rock, terpanes, hopanes, and steranes biomarkers were identified. The source rocks under study were deposited in a marine environment and were suboxic, with minor signs of continental input for the M'Cherga Formation. There is no connection between the Fahdene and Bahloul source rocks and the udied oil seeps. According to the biomarkers C27 18-22,29,30trisnorneohopane (Ts) and C27 17-22,29,30-trisnorhopane (Tm), these source rocks are mature and have reached the oil window. Regarding oil seeps, geochemical data indicate that, with the exception of four samples that showed some continental markings, the bulk of samples were deposited in an open marine environment. These most recent samples from oil seeps have a unique lithology (marl) that distinguishes them from the others (carbonate). There are two classes of oil seeps, according to statistical analysis of relationships between oil and oil and oil and source rocks. The first comprised samples that showed a positive connection with carbonate-lithological and marine-derived BouDabbous black shales. The second is a result of M'Cherga source rock and is made up of oil seeps with remnants of the terrestrial environment and a lithology with a marl trend. The Fahdene and Bahloul source rocks have no connection to the observed oil seeps. There are two different types of hydrocarbon spills depending on their link to tectonic deformations (oil seeps) and outcropping mature source rocks (oil impregnations), in addition to the existence of two generations of hydrocarbon spills in Northwest Tunisia (Lower Cretaceous/Ypresian).Keywords: petroleum seeps, source rocks, biomarkers, statistic, Northern Tunisia
Procedia PDF Downloads 691566 System Dietadhoc® - A Fusion of Human-Centred Design and Agile Development for the Explainability of AI Techniques Based on Nutritional and Clinical Data
Authors: Michelangelo Sofo, Giuseppe Labianca
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In recent years, the scientific community's interest in the exploratory analysis of biomedical data has increased exponentially. Considering the field of research of nutritional biologists, the curative process, based on the analysis of clinical data, is a very delicate operation due to the fact that there are multiple solutions for the management of pathologies in the food sector (for example can recall intolerances and allergies, management of cholesterol metabolism, diabetic pathologies, arterial hypertension, up to obesity and breathing and sleep problems). In this regard, in this research work a system was created capable of evaluating various dietary regimes for specific patient pathologies. The system is founded on a mathematical-numerical model and has been created tailored for the real working needs of an expert in human nutrition using the human-centered design (ISO 9241-210), therefore it is in step with continuous scientific progress in the field and evolves through the experience of managed clinical cases (machine learning process). DietAdhoc® is a decision support system nutrition specialists for patients of both sexes (from 18 years of age) developed with an agile methodology. Its task consists in drawing up the biomedical and clinical profile of the specific patient by applying two algorithmic optimization approaches on nutritional data and a symbolic solution, obtained by transforming the relational database underlying the system into a deductive database. For all three solution approaches, particular emphasis has been given to the explainability of the suggested clinical decisions through flexible and customizable user interfaces. Furthermore, the system has multiple software modules based on time series and visual analytics techniques that allow to evaluate the complete picture of the situation and the evolution of the diet assigned for specific pathologies.Keywords: medical decision support, physiological data extraction, data driven diagnosis, human centered AI, symbiotic AI paradigm
Procedia PDF Downloads 231565 The Structure and Function Investigation and Analysis of the Automatic Spin Regulator (ASR) in the Powertrain System of Construction and Mining Machines with the Focus on Dump Trucks
Authors: Amir Mirzaei
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The powertrain system is one of the most basic and essential components in a machine. The occurrence of motion is practically impossible without the presence of this system. When power is generated by the engine, it is transmitted by the powertrain system to the wheels, which are the last parts of the system. Powertrain system has different components according to the type of use and design. When the force generated by the engine reaches to the wheels, the amount of frictional force between the tire and the ground determines the amount of traction and non-slip or the amount of slip. At various levels, such as icy, muddy, and snow-covered ground, the amount of friction coefficient between the tire and the ground decreases dramatically and considerably, which in turn increases the amount of force loss and the vehicle traction decreases drastically. This condition is caused by the phenomenon of slipping, which, in addition to the waste of energy produced, causes the premature wear of driving tires. It also causes the temperature of the transmission oil to rise too much, as a result, causes a reduction in the quality and become dirty to oil and also reduces the useful life of the clutches disk and plates inside the transmission. this issue is much more important in road construction and mining machinery than passenger vehicles and is always one of the most important and significant issues in the design discussion, in order to overcome. One of these methods is the automatic spin regulator system which is abbreviated as ASR. The importance of this method and its structure and function have solved one of the biggest challenges of the powertrain system in the field of construction and mining machinery. That this research is examined.Keywords: automatic spin regulator, ASR, methods of reducing slipping, methods of preventing the reduction of the useful life of clutches disk and plate, methods of preventing the premature dirtiness of transmission oil, method of preventing the reduction of the useful life of tires
Procedia PDF Downloads 791564 Material Concepts and Processing Methods for Electrical Insulation
Authors: R. Sekula
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Epoxy composites are broadly used as an electrical insulation for the high voltage applications since only such materials can fulfill particular mechanical, thermal, and dielectric requirements. However, properties of the final product are strongly dependent on proper manufacturing process with minimized material failures, as too large shrinkage, voids and cracks. Therefore, application of proper materials (epoxy, hardener, and filler) and process parameters (mold temperature, filling time, filling velocity, initial temperature of internal parts, gelation time), as well as design and geometric parameters are essential features for final quality of the produced components. In this paper, an approach for three-dimensional modeling of all molding stages, namely filling, curing and post-curing is presented. The reactive molding simulation tool is based on a commercial CFD package, and include dedicated models describing viscosity and reaction kinetics that have been successfully implemented to simulate the reactive nature of the system with exothermic effect. Also a dedicated simulation procedure for stress and shrinkage calculations, as well as simulation results are presented in the paper. Second part of the paper is dedicated to recent developments on formulations of functional composites for electrical insulation applications, focusing on thermally conductive materials. Concepts based on filler modifications for epoxy electrical composites have been presented, including the results of the obtained properties. Finally, having in mind tough environmental regulations, in addition to current process and design aspects, an approach for product re-design has been presented focusing on replacement of epoxy material with the thermoplastic one. Such “design-for-recycling” method is one of new directions associated with development of new material and processing concepts of electrical products and brings a lot of additional research challenges. For that, one of the successful products has been presented to illustrate the presented methodology.Keywords: curing, epoxy insulation, numerical simulations, recycling
Procedia PDF Downloads 2781563 Enzyme Producing Psyhrophilic Pseudomonas app. Isolated from Poultry Meats
Authors: Ali Aydin, Mert Sudagidan, Aysen Coban, Alparslan Kadir Devrim
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Pseudomonas spp. (specifically, P. fluorescens and P. fragi) are considered the principal spoilage microorganisms of refrigerated poultry meats. The higher the level psychrophilic spoilage Pseudomonas spp. on carcasses at the end of processing lead to decrease the shelf life of the refrigerated product. The aim of the study was the identification of psychrophilic Pseudomonas spp. having proteolytic and lipolytic activities from poultry meats by 16S rRNA and rpoB gene sequencing, investigation of protease and lipase related genes and determination of proteolytic activity of Pseudomonas spp. In the of isolation procedure, collected chicken meat samples from local markets and slaughterhouses were homogenized and the lysates were incubated on Standard method agar and Skim Milk agar for selection of proteolytic bacteria and tributyrin agar for selection of lipolytic bacteria at +4 °C for 7 days. After detection of proteolytic and lipolytic colonies, the isolates were firstly analyzed by biochemical tests such as Gram staining, catalase and oxidase tests. DNA gene sequencing analysis and comparison with GenBank revealed that 126 strong enzyme Pseudomonas spp. were identified as predominantly P. fluorescens (n=55), P. fragi (n=42), Pseudomonas spp. (n=24), P. cedrina (n=2), P. poae (n=1), P. koreensis (n=1), and P. gessardi (n=1). Additionally, protease related aprX gene was screened in the strains and it was detected in 69/126 strains, whereas, lipase related lipA gene was found in 9 Pseudomonas strains. Protease activity was determined using commercially available protease assay kit and 5 strains showed high protease activity. The results showed that psychrophilic Pseudomonas strains were present in chicken meat samples and they can produce important levels of proteases and lipases for food spoilage to decrease food quality and safety.Keywords: Pseudomonas, chicken meat, protease, lipase
Procedia PDF Downloads 3871562 Building a Comprehensive Repository for Montreal Gamelan Archives
Authors: Laurent Bellemare
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After the showcase of traditional Indonesian performing arts at the Vancouver Expo 1986, Canadian universities inherited sets of Indonesian gamelan orchestras and soon began offering courses for music students interested in learning these diverse traditions. Among them, Université de Montréal was offered two sets of Balinese orchestras, a novelty that allowed a community of Montreal gamelan enthusiasts to form and engage with this music. A few generations later, a large body of archives have amassed, framing the history of this niche community’s achievements. This data, scattered in public and private archive collections, comes in various formats: Digital Audio Tape, audio cassettes, Video Home System videotape, digital files, photos, reel-to-reel audiotape, posters, concert programs, letters, TV shows, reports and more. Attempting to study these documents in order to unearth a chronology of gamelan in Montreal has proven to be challenging since no suitable platform for preservation, storage, and research currently exists. These files are, therefore, hard to find due to their decentralized locations. Additionally, most of the documents in older formats have yet to be digitized. In the case of recent digital files, such as pictures or rehearsal recordings, their locations can be even messier and their quantity overwhelming. Aside from the basic issue of choosing a suitable repository platform, questions of legal rights and methodology arise. For posterity, these documents should nonetheless be digitized, organized, and stored in an easily accessible online repository. This paper aims to underline the various challenges encountered in the early stages of such a project as well as to suggest ways of overcoming the obstacles to a thorough archival investigation.Keywords: archival work, archives, Balinese gamelan, Canada, Gamelan, Indonesia, Javanese gamelan, Montreal
Procedia PDF Downloads 1191561 Simulation of the FDA Centrifugal Blood Pump Using High Performance Computing
Authors: Mehdi Behbahani, Sebastian Rible, Charles Moulinec, Yvan Fournier, Mike Nicolai, Paolo Crosetto
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Computational Fluid Dynamics blood-flow simulations are increasingly used to develop and validate blood-contacting medical devices. This study shows that numerical simulations can provide additional and accurate estimates of relevant hemodynamic indicators (e.g., recirculation zones or wall shear stresses), which may be difficult and expensive to obtain from in-vivo or in-vitro experiments. The most recent FDA (Food and Drug Administration) benchmark consisted of a simplified centrifugal blood pump model that contains fluid flow features as they are commonly found in these devices with a clear focus on highly turbulent phenomena. The FDA centrifugal blood pump study is composed of six test cases with different volumetric flow rates ranging from 2.5 to 7.0 liters per minute, pump speeds, and Reynolds numbers ranging from 210,000 to 293,000. Within the frame of this study different turbulence models were tested including RANS models, e.g. k-omega, k-epsilon and a Reynolds Stress Model (RSM) and, LES. The partitioners Hilbert, METIS, ParMETIS and SCOTCH were used to create an unstructured mesh of 76 million elements and compared in their efficiency. Computations were performed on the JUQUEEN BG/Q architecture applying the highly parallel flow solver Code SATURNE and typically using 32768 or more processors in parallel. Visualisations were performed by means of PARAVIEW. Different turbulence models including all six flow situations could be successfully analysed and validated against analytical considerations and from comparison to other data-bases. It showed that an RSM represents an appropriate choice with respect to modeling high-Reynolds number flow cases. Especially, the Rij-SSG (Speziale, Sarkar, Gatzki) variant turned out to be a good approach. Visualisation of complex flow features could be obtained and the flow situation inside the pump could be characterized.Keywords: blood flow, centrifugal blood pump, high performance computing, scalability, turbulence
Procedia PDF Downloads 3821560 Using Recycled Wastes (Glass Powder) as Partially Replacement for Cement
Authors: Passant Youssef, Ahmed El-Tair, Amr El-Nemr
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Lately, with the environmental changes, enthusiasts trigger to stop the contamination of environment. Thus, various efforts were exerted for innovating environmental friendly concrete to sustain as a ‘Green Building’ material. Green building materials consider the cement industry as one of the most sources of air pollutant with high rate of carbon dioxide (CO₂) emissions. Several methods were developed to extensively reduce the influence of cement industry on environment. These methods such as using supplementary cementitious material or improving the cement manufacturing process are still under investigation. However, with the presence of recycled wastes from construction and finishing materials, the use of supplementary cementitious materials seems to provide an economic solution. Furthermore, it improves the mechanical properties of cement paste, in addition to; it modulates the workability and durability of concrete. In this paper, the glass powder was considered to be used as partial replacement of cement. This study provided the mechanical influence for using the glass powder as partial replacement of cement. In addition, it examines the microstructure of cement mortar using scanning electron microscope and X-ray diffraction. The cement in concrete is replaced by waste glass powder in steps of 5%, 10%, 15%, 20% and 25% by weight of cement and its effects on compressive and flexure strength were determined after 7 and 28 days. It was found that the 5% glass powder replacement increased the 7 days compressive strength by 20.5%, however, there was no increase in compressive strength after 28 days; which means that the glass powder did not react in the cement mortar due to its amorphous nature on the long run, and it can act as fine aggregate better that cement replacement. As well as, the 5% and 10% glass powder replacement increased the 28 days flexural strength by 46.9%. SEM micrographs showed very dense matrix for the optimum specimen compared to control specimen as well; some glass particles were clearly observed. High counts of silica were optimized from XRD while amorphous materials such as calcium silicate cannot be directly detected.Keywords: supplementary materials, glass powder, concrete, cementitious materials
Procedia PDF Downloads 2101559 Following the Caravans: Interdisciplinary Study to Integrate Chinese and African Relations in Ethiopia
Authors: E. Mattio
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The aim of this project is to study the Chinese presence in Ethiopia, following the path of the last salt caravans from Danakil to Tigray region. Official estimates of the number of Chinese in Africa vary widely; on the continent, there are increasingly diverse groups of Chinese migrants in terms of language, dialect, class, education, and employment. Based on this and on a very general state of the art, it was decided to increase the studies on this phenomenon, documenting the extraction of salt and following the sellers in the north of the country. The project is unique and allows you to admire a landscape that will soon change, due to the construction of infrastructure that is changing the dynamics of movement and sales. To carry out this study, interdisciplinary investigation methods were integrated, such as landscape archeology, historiographic research, participatory anthropology, geopolitics, and cultural anthropology and ethnology. There are two main objectives of the research. The first was an analysis of risk perceptions to predict what will happen to these populations and how the territory will be modified, trying to monitor the growth of infrastructure in the country and the effects it will have on the population. Thanks to the use of GIS, some roads created by Chinese companies that worked in the area have been georeferenced. The second point was to document the life and rituals of Ethiopian populations, in order not to lose the aspects of uniqueness that risk being lost. The local interviews have garnered impressions and criticisms from the local population to understand whether the Chinese presence is perceived as a threat or a solution. Among the most exclusive interviews, there are those made to Afar leaders in the Logya area and some Coptic representatives in the Wukro area. To make this project even more unique, the Coptic rituals of Gennà and Timkat have been documented, unique expressions of a millennial tradition. The aim was to understand whether the Maoist presence began to influence the religious rites and forms of belief present in the country.Keywords: China, Ethiopia, GIS, risk perceptions
Procedia PDF Downloads 1561558 Investigation of the Material Behaviour of Polymeric Interlayers in Broken Laminated Glass
Authors: Martin Botz, Michael Kraus, Geralt Siebert
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The use of laminated glass gains increasing importance in structural engineering. For safety reasons, at least two glass panes are laminated together with a polymeric interlayer. In case of breakage of one or all of the glass panes, the glass fragments are still connected to the interlayer due to adhesion forces and a certain residual load-bearing capacity is left in the system. Polymer interlayers used in the laminated glass show a viscoelastic material behavior, e.g. stresses and strains in the interlayer are dependent on load duration and temperature. In the intact stage only small strains appear in the interlayer, thus the material can be described in a linear way. In the broken stage, large strains can appear and a non-linear viscoelasticity material theory is necessary. Relaxation tests on two different types of polymeric interlayers are performed at different temperatures and strain amplitudes to determine the border to the non-linear material regime. Based on the small-scale specimen results further tests on broken laminated glass panes are conducted. So-called ‘through-crack-bending’ (TCB) tests are performed, in which the laminated glass has a defined crack pattern. The test set-up is realized in a way that one glass layer is still able to transfer compressive stresses but tensile stresses have to be transferred by the interlayer solely. The TCB-tests are also conducted under different temperatures but constant force (creep test). Aims of these experiments are to elaborate if the results of small-scale tests on the interlayer are transferable to a laminated glass system in the broken stage. In this study, limits of the applicability of linear-viscoelasticity are established in the context of two commercially available polymer-interlayers. Furthermore, it is shown that the results of small-scale tests agree to a certain degree to the results of the TCB large-scale experiments. In a future step, the results can be used to develop material models for the post breakage performance of laminated glass.Keywords: glass breakage, laminated glass, relaxation test, viscoelasticity
Procedia PDF Downloads 1211557 Natural Bio-Active Product from Marine Resources
Authors: S. Ahmed John
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Marine forms-bacteria, actinobacteria, cynobacteria, fungi, microalgae, seaweeds mangroves and other halophytes an extremely important oceanic resources and constituting over 90% of the oceanic biomass. The marine natural products have lead to the discovery of many compounds considered worthy for clinical applications. The marine sources have the highest probability of yielding natural products. Natural derivatives play an important role to prevent the cancer incidences as synthetic drug transformation in mangrove. 28.12% of anticancer compound extracted from the mangroves. Exchocaria agollocha has the anti cancer compounds. The present investigation reveals the potential of the Exchocaria agollocha with biotechnological applications for anti cancer, antimicrobial drug discovery, environmental remediation, and developing new resources for the industrial process. The anti-cancer activity of Exchocaria agollocha was screened from 3.906 to 1000 µg/ml of concentration with the dilution leads to 1:1 to 1:128 following methanol and chloroform extracts. The cell viability in the Exchocaria agollocha was maximum at the lower concentration where as low at the higher concentration of methanol and chloroform extracts when compare to control. At 3.906 concentration, 85.32 and 81.96 of cell viability was found at 1:128 dilution of methanol and chloroform extracts respectively. At the concentration of 31.25 following 1:16 dilution, the cell viability was 65.55 in methanol and 45.55 in chloroform extracts. However, at the higher concentration, the cell viability 22.35 and 8.12 was recorded in the extracts of methanol and chloroform. The cell viability was more in methanol when compare to chloroform extracts at lower concentration. The present findings gives current trends in screening and the activity analysis of metabolites from mangrove resources and to expose the models to bring a new sustain for tackling cancer. Bioactive compounds of Exchocaria agollocha have extensive use in treatment of many diseases and serve as a compound and templates for synthetic modification.Keywords: bio-active product, compounds, natural products and microalgae
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