Search results for: transportation modes
147 Representational Issues in Learning Solution Chemistry at Secondary School
Authors: Lam Pham, Peter Hubber, Russell Tytler
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Students’ conceptual understandings of chemistry concepts/phenomena involve capability to coordinate across the three levels of Johnston’s triangle model. This triplet model is based on reasoning about chemical phenomena across macro, sub-micro and symbolic levels. In chemistry education, there is a need for further examining inquiry-based approaches that enhance students’ conceptual learning and problem solving skills. This research adopted a directed inquiry pedagogy based on students constructing and coordinating representations, to investigate senior school students’ capabilities to flexibly move across Johnston’ levels when learning dilution and molar concentration concepts. The participants comprise 50 grade 11 and 20 grade 10 students and 4 chemistry teachers who were selected from 4 secondary schools located in metropolitan Melbourne, Victoria. This research into classroom practices used ethnographic methodology, involved teachers working collaboratively with the research team to develop representational activities and lesson sequences in the instruction of a unit on solution chemistry. The representational activities included challenges (Representational Challenges-RCs) that used ‘representational tools’ to assist students to move across Johnson’s three levels for dilution phenomena. In this report, the ‘representational tool’ called ‘cross and portion’ model was developed and used in teaching and learning the molar concentration concept. Students’ conceptual understanding and problem solving skills when learning with this model are analysed through group case studies of year 10 and 11 chemistry students. In learning dilution concepts, students in both group case studies actively conducted a practical experiment, used their own language and visualisation skills to represent dilution phenomena at macroscopic level (RC1). At the sub-microscopic level, students generated and negotiated representations of the chemical interactions between solute and solvent underpinning the dilution process. At the symbolic level, students demonstrated their understandings about dilution concepts by drawing chemical structures and performing mathematical calculations. When learning molar concentration with a ‘cross and portion’ model (RC2), students coordinated across visual and symbolic representational forms and Johnson’s levels to construct representations. The analysis showed that in RC1, Year 10 students needed more ‘scaffolding’ in inducing to representations to explicit the form and function of sub-microscopic representations. In RC2, Year 11 students showed clarity in using visual representations (drawings) to link to mathematics to solve representational challenges about molar concentration. In contrast, year 10 students struggled to get match up the two systems, symbolic system of mole per litre (‘cross and portion’) and visual representation (drawing). These conceptual problems do not lie in the students’ mathematical calculation capability but rather in students’ capability to align visual representations with the symbolic mathematical formulations. This research also found that students in both group case studies were able to coordinate representations when probed about the use of ‘cross and portion’ model (in RC2) to demonstrate molar concentration of diluted solutions (in RC1). Students mostly succeeded in constructing ‘cross and portion’ models to represent the reduction of molar concentration of the concentration gradients. In conclusion, this research demonstrated how the strategic introduction and coordination of chemical representations across modes and across the macro, sub-micro and symbolic levels, supported student reasoning and problem solving in chemistry.Keywords: cross and portion, dilution, Johnston's triangle, molar concentration, representations
Procedia PDF Downloads 137146 Combat Plastic Entering in Kanpur City, Uttar Pradesh, India Marine Environment
Authors: Arvind Kumar
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The city of Kanpur is located in the terrestrial plain area on the bank of the river Ganges and is the second largest city in the state of Uttar Pradesh. The city generates approximately 1400-1600 tons per day of MSW. Kanpur has been known as a major point and non-points-based pollution hotspot for the river Ganges. The city has a major industrial hub, probably the largest in the state, catering to the manufacturing and recycling of plastic and other dry waste streams. There are 4 to 5 major drains flowing across the city, which receive a significant quantity of waste leakage, which subsequently adds to the Ganges flow and is carried to the Bay of Bengal. A river-to-sea flow approach has been established to account for leaked waste into urban drains, leading to the build-up of marine litter. Throughout its journey, the river accumulates plastic – macro, meso, and micro, from various sources and transports it towards the sea. The Ganges network forms the second-largest plastic-polluting catchment in the world, with over 0.12 million tonnes of plastic discharged into marine ecosystems per year and is among 14 continental rivers into which over a quarter of global waste is discarded 3.150 Kilo tons of plastic waste is generated in Kanpur, out of which 10%-13% of plastic is leaked into the local drains and water flow systems. With the Support of Kanpur Municipal Corporation, 1TPD capacity MRF for drain waste management was established at Krishna Nagar, Kanpur & A German startup- Plastic Fisher, was identified for providing a solution to capture the drain waste and achieve its recycling in a sustainable manner with a circular economy approach. The team at Plastic Fisher conducted joint surveys and identified locations on 3 drains at Kanpur using GIS maps developed during the survey. It suggested putting floating 'Boom Barriers' across the drains with a low-cost material, which reduced their cost to only 2000 INR per barrier. The project was built upon the self-sustaining financial model. The project includes activities where a cost-efficient model is developed and adopted for a socially self-inclusive model. The project has recommended the use of low-cost floating boom barriers for capturing waste from drains. This involves a one-time time cost and has no operational cost. Manpower is engaged in fishing and capturing immobilized waste, whose salaries are paid by the Plastic Fisher. The captured material is sun-dried and transported to the designated place, where the shed and power connection, which act as MRF, are provided by the city Municipal corporation. Material aggregation, baling, and transportation costs to end-users are borne by Plastic Fisher as well.Keywords: Kanpur, marine environment, drain waste management, plastic fisher
Procedia PDF Downloads 71145 Superlyophobic Surfaces for Increased Heat Transfer during Condensation of CO₂
Authors: Ingrid Snustad, Asmund Ervik, Anders Austegard, Amy Brunsvold, Jianying He, Zhiliang Zhang
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CO₂ capture, transport and storage (CCS) is essential to mitigate global anthropogenic CO₂ emissions. To make CCS a widely implemented technology in, e.g. the power sector, the reduction of costs is crucial. For a large cost reduction, every part of the CCS chain must contribute. By increasing the heat transfer efficiency during liquefaction of CO₂, which is a necessary step, e.g. ship transportation, the costs associated with the process are reduced. Heat transfer rates during dropwise condensation are up to one order of magnitude higher than during filmwise condensation. Dropwise condensation usually occurs on a non-wetting surface (Superlyophobic surface). The vapour condenses in discrete droplets, and the non-wetting nature of the surface reduces the adhesion forces and results in shedding of condensed droplets. This, again, results in fresh nucleation sites for further droplet condensation, effectively increasing the liquefaction efficiency. In addition, the droplets in themselves have a smaller heat transfer resistance than a liquid film, resulting in increased heat transfer rates from vapour to solid. Surface tension is a crucial parameter for dropwise condensation, due to its impact on the solid-liquid contact angle. A low surface tension usually results in a low contact angle, and again to spreading of the condensed liquid on the surface. CO₂ has very low surface tension compared to water. However, at relevant temperatures and pressures for CO₂ condensation, the surface tension is comparable to organic compounds such as pentane, a dropwise condensation of CO₂ is a completely new field of research. Therefore, knowledge of several important parameters such as contact angle and drop size distribution must be gained in order to understand the nature of the condensation. A new setup has been built to measure these relevant parameters. The main parts of the experimental setup is a pressure chamber in which the condensation occurs, and a high- speed camera. The process of CO₂ condensation is visually monitored, and one can determine the contact angle, contact angle hysteresis and hence, the surface adhesion of the liquid. CO₂ condensation on different surfaces can be analysed, e.g. copper, aluminium and stainless steel. The experimental setup is built for accurate measurements of the temperature difference between the surface and the condensing vapour and accurate pressure measurements in the vapour. The temperature will be measured directly underneath the condensing surface. The next step of the project will be to fabricate nanostructured surfaces for inducing superlyophobicity. Roughness is a key feature to achieve contact angles above 150° (limit for superlyophobicity) and controlled, and periodical roughness on the nanoscale is beneficial. Surfaces that are non- wetting towards organic non-polar liquids are candidates surface structures for dropwise condensation of CO₂.Keywords: CCS, dropwise condensation, low surface tension liquid, superlyophobic surfaces
Procedia PDF Downloads 278144 The Highly Dispersed WO3-x Photocatalyst over the Confinement Effect of Mesoporous SBA-15 Molecular Sieves for Photocatalytic Nitrogen Reduction
Authors: Xiaoling Ren, Guidong Yang
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As one of the largest industrial synthetic chemicals in the world, ammonia has the advantages of high energy density, easy liquefaction, and easy transportation, which is widely used in agriculture, chemical industry, energy storage, and other fields. The industrial Haber-Bosch method process for ammonia synthesis is generally conducted under severe conditions. It is essential to develop a green, sustainable strategy for ammonia production to meet the growing demand. In this direction, photocatalytic nitrogen reduction has huge advantages over the traditional, well-established Haber-Bosch process, such as the utilization of natural sun light as the energy source and significantly lower pressure and temperature to affect the reaction process. However, the high activation energy of nitrogen and the low efficiency of photo-generated electron-hole separation in the photocatalyst result in low ammonia production yield. Many researchers focus on improving the catalyst. In addition to modifying the catalyst, improving the dispersion of the catalyst and making full use of active sites are also means to improve the overall catalytic activity. Few studies have been carried out on this, which is the aim of this work. In this work, by making full use of the nitrogen activation ability of WO3-x with defective sites, small size WO3-x photocatalyst with high dispersibility was constructed, while the growth of WO3-x was restricted by using a high specific surface area mesoporous SBA-15 molecular sieve with the regular pore structure as a template. The morphology of pure SBA-15 and WO3-x/SBA-15 was characterized byscanning electron microscopy (SEM). Compared with pure SBA-15, some small particles can be found in the WO3-x/SBA-15 material, which means that WO3-x grows into small particles under the limitation of SBA-15, which is conducive to the exposure of catalytically active sites. To elucidate the chemical nature of the material, the X-ray diffraction (XRD) analysis was conducted. The observed diffraction pattern inWO3-xis in good agreement with that of the JCPDS file no.71-2450. Compared with WO3-x, no new peaks appeared in WO3-x/SBA-15.It can be concluded that WO3-x/SBA-15 was synthesized successfully. In order to provide more active sites, the mass content of WO3-x was optimized. Then the photocatalytic nitrogen reduction performances of above samples were performed with methanol as a hole scavenger. The results show that the overall ammonia production performance of WO3-x/SBA-15 is improved than pure bulk WO3-x. The above results prove that making full use of active sites is also a means to improve overall catalytic activity.This work provides material basis for the design of high-efficiency photocatalytic nitrogen reduction catalysts.Keywords: ammonia, photocatalytic, nitrogen reduction, WO3-x, high dispersibility
Procedia PDF Downloads 159143 Fatigue Truck Modification Factor for Design Truck (CL-625)
Authors: Mohamad Najari, Gilbert Grondin, Marwan El-Rich
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Design trucks in standard codes are selected based on the amount of damage they cause on structures-specifically bridges- and roads to represent the real traffic loads. Some limited numbers of trucks are run on a bridge one at a time and the damage on the bridge is recorded for each truck. One design track is also run on the same bridge “n” times -“n” is the number of trucks used previously- to calculate the damage of the design truck on the same bridge. To make these damages equal a reduction factor is needed for that specific design truck in the codes. As the limited number of trucks cannot be the exact representative of real traffic through the life of the structure, these reduction factors are not accurately calculated and they should be modified accordingly. Started on July 2004, the vehicle load data were collected in six weigh in motion (WIM) sites owned by Alberta Transportation for eight consecutive years. This database includes more than 200 million trucks. Having these data gives the opportunity to compare the effect of any standard fatigue trucks weigh and the real traffic load on the fatigue life of the bridges which leads to a modification for the fatigue truck factor in the code. To calculate the damage for each truck, the truck is run on the bridge, moment history of the detail under study is recorded, stress range cycles are counted, and then damage is calculated using available S-N curves. A 2000 lines FORTRAN code has been developed to perform the analysis and calculate the damages of the trucks in the database for all eight fatigue categories according to Canadian Institute of Steel Construction (CSA S-16). Stress cycles are counted using rain flow counting method. The modification factors for design truck (CL-625) are calculated for two different bridge configurations and ten span lengths varying from 1 m to 200 m. The two considered bridge configurations are single-span bridge and four span bridge. This was found to be sufficient and representative for a simply supported span, positive moment in end spans of bridges with two or more spans, positive moment in interior spans of three or more spans, and the negative moment at an interior support of multi-span bridges. The moment history of the mid span is recorded for single-span bridge and, exterior positive moment, interior positive moment, and support negative moment are recorded for four span bridge. The influence lines are expressed by a polynomial expression obtained from a regression analysis of the influence lines obtained from SAP2000. It is found that for design truck (CL-625) fatigue truck factor is varying from 0.35 to 0.55 depending on span lengths and bridge configuration. The detail results will be presented in the upcoming papers. This code can be used for any design trucks available in standard codes.Keywords: bridge, fatigue, fatigue design truck, rain flow analysis, FORTRAN
Procedia PDF Downloads 521142 Developing a Roadmap by Integrating of Environmental Indicators with the Nitrogen Footprint in an Agriculture Region, Hualien, Taiwan
Authors: Ming-Chien Su, Yi-Zih Chen, Nien-Hsin Kao, Hideaki Shibata
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The major component of the atmosphere is nitrogen, yet atmospheric nitrogen has limited availability for biological use. Human activities have produced different types of nitrogen related compounds such as nitrogen oxides from combustion, nitrogen fertilizers from farming, and the nitrogen compounds from waste and wastewater, all of which have impacted the environment. Many studies have indicated the N-footprint is dominated by food, followed by housing, transportation, and goods and services sectors. To solve the impact issues from agricultural land, nitrogen cycle research is one of the key solutions. The study site is located in Hualien County, Taiwan, a major rice and food production area of Taiwan. Importantly, environmentally friendly farming has been promoted for years, and an environmental indicator system has been established by previous authors based on the concept of resilience capacity index (RCI) and environmental performance index (EPI). Nitrogen management is required for food production, as excess N causes environmental pollution. Therefore it is very important to develop a roadmap of the nitrogen footprint, and to integrate it with environmental indicators. The key focus of the study thus addresses (1) understanding the environmental impact caused by the nitrogen cycle of food products and (2) uncovering the trend of the N-footprint of agricultural products in Hualien, Taiwan. The N-footprint model was applied, which included both crops and energy consumption in the area. All data were adapted from government statistics databases and crosschecked for consistency before modeling. The actions involved with agricultural production were evaluated and analyzed for nitrogen loss to the environment, as well as measuring the impacts to humans and the environment. The results showed that rice makes up the largest share of agricultural production by weight, at 80%. The dominant meat production is pork (52%) and poultry (40%); fish and seafood were at similar levels to pork production. The average per capita food consumption in Taiwan is 2643.38 kcal capita−1 d−1, primarily from rice (430.58 kcal), meats (184.93 kcal) and wheat (ca. 356.44 kcal). The average protein uptake is 87.34 g capita−1 d−1, and 51% is mainly from meat, milk, and eggs. The preliminary results showed that the nitrogen footprint of food production is 34 kg N per capita per year, congruent with the results of Shibata et al. (2014) for Japan. These results provide a better understanding of the nitrogen demand and loss in the environment, and the roadmap can furthermore support the establishment of nitrogen policy and strategy. Additionally, the results serve to develop a roadmap of the nitrogen cycle of an environmentally friendly farming area, thus illuminating the nitrogen demand and loss of such areas.Keywords: agriculture productions, energy consumption, environmental indicator, nitrogen footprint
Procedia PDF Downloads 302141 Holistic Approach to Teaching Mathematics in Secondary School as a Means of Improving Students’ Comprehension of Study Material
Authors: Natalia Podkhodova, Olga Sheremeteva, Mariia Soldaeva
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Creating favorable conditions for students’ comprehension of mathematical content is one of the primary problems in teaching mathematics in secondary school. Psychology research has demonstrated that positive comprehension becomes possible when new information becomes part of student’s subjective experience and when linkages between the attributes of notions and various ways of their presentations can be established. The fact of comprehension includes the ability to build a working situational model and thus becomes an important means of solving mathematical problems. The article describes the implementation of a holistic approach to teaching mathematics designed to address the primary challenges of such teaching, specifically, the challenge of students’ comprehension. This approach consists of (1) establishing links between the attributes of a notion: the sense, the meaning, and the term; (2) taking into account the components of student’s subjective experience -emotional and value, contextual, procedural, communicative- during the educational process; (3) links between different ways to present mathematical information; (4) identifying and leveraging the relationships between real, perceptual and conceptual (scientific) mathematical spaces by applying real-life situational modeling. The article describes approaches to the practical use of these foundational concepts. Identifying how proposed methods and technology influence understanding of material used in teaching mathematics was the research’s primary goal. The research included an experiment in which 256 secondary school students took part: 142 in the experimental group and 114 in the control group. All students in these groups had similar levels of achievement in math and studied math under the same curriculum. In the course of the experiment, comprehension of two topics -'Derivative' and 'Trigonometric functions'- was evaluated. Control group participants were taught using traditional methods. Students in the experimental group were taught using the holistic method: under the teacher’s guidance, they carried out problems designed to establish linkages between notion’s characteristics, to convert information from one mode of presentation to another, as well as problems that required the ability to operate with all modes of presentation. The use of the technology that forms inter-subject notions based on linkages between perceptional, real, and conceptual mathematical spaces proved to be of special interest to the students. Results of the experiment were analyzed by presenting students in each of the groups with a final test in each of the studied topics. The test included problems that required building real situational models. Statistical analysis was used to aggregate test results. Pierson criterion was used to reveal the statistical significance of results (pass-fail the modeling test). A significant difference in results was revealed (p < 0.001), which allowed the authors to conclude that students in the study group showed better comprehension of mathematical information than those in the control group. Also, it was revealed (used Student’s t-test) that the students of the experimental group performed reliably (p = 0.0001) more problems in comparison with those in the control group. The results obtained allow us to conclude that increasing comprehension and assimilation of study material took place as a result of applying implemented methods and techniques.Keywords: comprehension of mathematical content, holistic approach to teaching mathematics in secondary school, subjective experience, technology of the formation of inter-subject notions
Procedia PDF Downloads 176140 Accounting for Downtime Effects in Resilience-Based Highway Network Restoration Scheduling
Authors: Zhenyu Zhang, Hsi-Hsien Wei
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Highway networks play a vital role in post-disaster recovery for disaster-damaged areas. Damaged bridges in such networks can disrupt the recovery activities by impeding the transportation of people, cargo, and reconstruction resources. Therefore, rapid restoration of damaged bridges is of paramount importance to long-term disaster recovery. In the post-disaster recovery phase, the key to restoration scheduling for a highway network is prioritization of bridge-repair tasks. Resilience is widely used as a measure of the ability to recover with which a network can return to its pre-disaster level of functionality. In practice, highways will be temporarily blocked during the downtime of bridge restoration, leading to the decrease of highway-network functionality. The failure to take downtime effects into account can lead to overestimation of network resilience. Additionally, post-disaster recovery of highway networks is generally divided into emergency bridge repair (EBR) in the response phase and long-term bridge repair (LBR) in the recovery phase, and both of EBR and LBR are different in terms of restoration objectives, restoration duration, budget, etc. Distinguish these two phases are important to precisely quantify highway network resilience and generate suitable restoration schedules for highway networks in the recovery phase. To address the above issues, this study proposes a novel resilience quantification method for the optimization of long-term bridge repair schedules (LBRS) taking into account the impact of EBR activities and restoration downtime on a highway network’s functionality. A time-dependent integer program with recursive functions is formulated for optimally scheduling LBR activities. Moreover, since uncertainty always exists in the LBRS problem, this paper extends the optimization model from the deterministic case to the stochastic case. A hybrid genetic algorithm that integrates a heuristic approach into a traditional genetic algorithm to accelerate the evolution process is developed. The proposed methods are tested using data from the 2008 Wenchuan earthquake, based on a regional highway network in Sichuan, China, consisting of 168 highway bridges on 36 highways connecting 25 cities/towns. The results show that, in this case, neglecting the bridge restoration downtime can lead to approximately 15% overestimation of highway network resilience. Moreover, accounting for the impact of EBR on network functionality can help to generate a more specific and reasonable LBRS. The theoretical and practical values are as follows. First, the proposed network recovery curve contributes to comprehensive quantification of highway network resilience by accounting for the impact of both restoration downtime and EBR activities on the recovery curves. Moreover, this study can improve the highway network resilience from the organizational dimension by providing bridge managers with optimal LBR strategies.Keywords: disaster management, highway network, long-term bridge repair schedule, resilience, restoration downtime
Procedia PDF Downloads 150139 Carbon-Supported Pd Nano-Particles as Green Catalysts for the Production of Fuels from Biomass
Authors: Andrea Dragu, Solen Kinayyigit, Valerie Colliere, Karin Karin Philippot, Camelia Bala, Vasile I. Parvulescu
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The production of transportation fuels from biomass has gained a growing attention due to diminishing fossil fuel reserves, rising petroleum prices and increasing concern about global warming. In recent years, renewable hydrocarbons that are completely fungible with fossil fuels have been suggested to be efficiently produced by catalytic deoxygenation of fatty acids and their derivatives viadecarboxylation / decarbonylation. Several triglycerides (tall oil fatty acids) and saturated/unsaturated fatty acids and their corresponding esters were used as feedstocks. Their impact together with the influence of the reaction conditions and the catalyst composition on the nature of the reaction pathways of the deoxygenation of vegetable oils and their derivatives were recently reviewed. Following this state of the art the aim of the present study was the investigation of Pd NPs deposited onto mesoporous carbon supports as active and stable catalysts for the deoxygenation of oleic acid. The catalysts were prepared by the deposition of Pd NPs synthesised following an organometallic route on mesoporous carbons with different characteristics. Experiments were carried out under both batch and flow conditions. They demonstrated that under batch conditions (200 atm; 573K), the extent of the reaction depended, firstly, on the Pd loading and then on the metal dispersion and the oxidation state of palladium, both influenced by the way the support has been treated before the NPs deposition and by the preparation/stabilization methodology of Pd NPs. No aromatic compounds were detected in the reaction products but octadecanol and octadecane were observed in large extents. Under flow conditions (4 atm; 573 K), the conversion of stearic acid was superior to that observed in batch conditions. The product mixture contained over 20% heptadecane. No octadecanol, octadecane, and aromatic compounds were detected. The maxima in performances are obtained after only 0.5 h. After that, the yields in heptadecane suffer from a severe decrease until 3h reaction time. However, at that time, stopping feeding the reactor with oleic acid and flushing the catalyst only with mesitylene recovered the activity and the selectivity of the catalysts. With the complete removal of H2, the analysis revealed the presence of heptadecene in high excess compared to heptadecane (almost 7 to 1), thus suggesting decarbonylation as the main route. ICP-OES measurements indicated no leaching of palladium and simple washing of catalysts with mesitylene allowed recycling without any change in conversion or product distribution. Noteworthy, mesitylene as solvent exhibited no effect in this reaction. In conclusion, this study demonstrates the feasibility of such catalysts for the green production of fuels from biomass.Keywords: fuels from biomass, green catalyst, Pd nano-particles , recycble catalyst
Procedia PDF Downloads 302138 Influence of Synergistic Modification with Tung Oil and Heat Treatment on Physicochemical Properties of Wood
Authors: Luxi He, Tianfang Zhang, Zhengbin He, Songlin Yi
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Heat treatment has been widely recognized for its effectiveness in enhancing the physicochemical properties of wood, including hygroscopicity and dimensional stability. Nonetheless, the non-negligible volumetric shrinkage and loss of mechanical strength resulting from heat treatment may diminish the wood recovery and its product value. In this study, tung oil was used to alleviate heat-induced shrinkage and reduction in mechanical properties of wood during heat treatment. Tung oil was chosen as a modifier because it is a traditional Chinese plant oil that has been widely used for over a thousand years to protect wooden furniture and buildings due to its biodegradable and non-toxic properties. The effects of different heating media (air, tung oil) and their effective treatment parameters (temperature, duration) on the changes in the physical properties (morphological characteristics, pore structures, micromechanical properties), and chemical properties (chemical structures, chemical composition) of wood were investigated by using scanning electron microscopy, confocal laser scanning microscopy, atomic force microscopy, X-ray photoelectron spectroscopy, and dynamic vapor sorption. Meanwhile, the correlation between the mass changes and the color change, volumetric shrinkage, and hygroscopicity was also investigated. The results showed that the thermal degradation of wood cell wall components was the most important factor contributing to the changes in heat-induced shrinkage, color, and moisture adsorption of wood. In air-heat-treated wood samples, there was a significant correlation between mass change and heat-induced shrinkage, brightness, and moisture adsorption. However, the presence of impregnated tung oil in oil-heat-treated wood appears to disrupt these correlations among physical properties. The results of micromechanical properties demonstrated a significant decrease in elastic modulus following high-temperature heat treatment, which was mitigated by tung oil treatment. Chemical structure and compositional analyses indicated that the changes in chemical structure primarily stem from the degradation of hemicellulose and cellulose, and the presence of tung oil created an oxygen-insulating environment that slowed down this degradation process. Morphological observation results showed that tung oil permeated the wood structure and penetrated the cell walls through transportation channels, altering the micro-morphology of the cell wall surface, obstructing primary water passages (e.g., vessels and pits), and impeding the release of volatile degradation products as well as the infiltration and diffusion of water. In summary, tung oil treatment represents an environmentally friendly and efficient method for maximizing wood recovery and increasing product value. This approach holds significant potential for industrial applications in wood heat treatment.Keywords: tung oil, heat treatment, physicochemical properties, wood cell walls
Procedia PDF Downloads 69137 Analysis Rescuers' Viewpoint about Victims Tracking in Earthquake by Using Radio Frequency Identification (RFID)
Authors: Sima Ajami, Batool Akbari
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Background: Radio frequency identification (RFID) system has been successfully applied to the areas of manufacturing, supply chain, agriculture, transportation, healthcare, and services. The RFID is already used to track and trace the victims in a disaster situation. Data can be collected in real time and be immediately available to emergency personnel and saves time by the RFID. Objectives: The aim of this study was, first, to identify stakeholders and customers for rescuing earthquake victims, second, to list key internal and external factors to use RFID to track earthquake victims, finally, to assess SWOT for rescuers' viewpoint. Materials and Methods: This study was an applied and analytical study. The study population included scholars, experts, planners, policy makers and rescuers in the "red crescent society of Isfahan province", "disaster management Isfahan province", "maintenance and operation department of Isfahan", "fire and safety services organization of Isfahan municipality", and "medical emergencies and disaster management center of Isfahan". After that, researchers held a workshop to teach participants about RFID and its usages in tracking earthquake victims. In the meanwhile of the workshop, participants identified, listed, and weighed key internal factors (strengths and weaknesses; SW) and external factors (opportunities and threats; OT) to use RFID in tracking earthquake victims. Therefore, participants put weigh strengths, weaknesses, opportunities, and threats (SWOT) and their weighted scales were calculated. Then, participants' opinions about this issue were assessed. Finally, according to the SWOT matrix, strategies to solve the weaknesses, problems, challenges, and threats through opportunities and strengths were proposed by participants. Results: The SWOT analysis showed that the total weighted score for internal and external factors were 3.91 (Internal Factor Evaluation) and 3.31 (External Factor Evaluation) respectively. Therefore, it was in a quadrant SO strategies cell in the SWOT analysis matrix and aggressive strategies were resulted. Organizations, scholars, experts, planners, policy makers and rescue workers should plan to use RFID technology in order to save more victims and manage their life. Conclusions: Researchers suppose to apply SO strategies and use a firm’s internal strength to take advantage of external opportunities. It is suggested, policy maker should plan to use the most developed technologies to save earthquake victims and deliver the easiest service to them. To do this, education, informing, and encouraging rescuers to use these technologies is essential. Originality/ Value: This study was a research paper that showed how RFID can be useful to track victims in earthquake.Keywords: frequency identification system, strength, weakness, earthquake, victim
Procedia PDF Downloads 322136 The Use of Geographic Information System Technologies for Geotechnical Monitoring of Pipeline Systems
Authors: A. G. Akhundov
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Issues of obtaining unbiased data on the status of pipeline systems of oil- and oil product transportation become especially important when laying and operating pipelines under severe nature and climatic conditions. The essential attention is paid here to researching exogenous processes and their impact on linear facilities of the pipeline system. Reliable operation of pipelines under severe nature and climatic conditions, timely planning and implementation of compensating measures are only possible if operation conditions of pipeline systems are regularly monitored, and changes of permafrost soil and hydrological operation conditions are accounted for. One of the main reasons for emergency situations to appear is the geodynamic factor. Emergency situations are proved by the experience to occur within areas characterized by certain conditions of the environment and to develop according to similar scenarios depending on active processes. The analysis of natural and technical systems of main pipelines at different stages of monitoring gives a possibility of making a forecast of the change dynamics. The integration of GIS technologies, traditional means of geotechnical monitoring (in-line inspection, geodetic methods, field observations), and remote methods (aero-visual inspection, aero photo shooting, air and ground laser scanning) provides the most efficient solution of the problem. The united environment of geo information system (GIS) is a comfortable way to implement the monitoring system on the main pipelines since it provides means to describe a complex natural and technical system and every element thereof with any set of parameters. Such GIS enables a comfortable simulation of main pipelines (both in 2D and 3D), the analysis of situations and selection of recommendations to prevent negative natural or man-made processes and to mitigate their consequences. The specifics of such systems include: a multi-dimensions simulation of facilities in the pipeline system, math modelling of the processes to be observed, and the use of efficient numeric algorithms and software packets for forecasting and analyzing. We see one of the most interesting possibilities of using the monitoring results as generating of up-to-date 3D models of a facility and the surrounding area on the basis of aero laser scanning, data of aerophotoshooting, and data of in-line inspection and instrument measurements. The resulting 3D model shall be the basis of the information system providing means to store and process data of geotechnical observations with references to the facilities of the main pipeline; to plan compensating measures, and to control their implementation. The use of GISs for geotechnical monitoring of pipeline systems is aimed at improving the reliability of their operation, reducing the probability of negative events (accidents and disasters), and at mitigation of consequences thereof if they still are to occur.Keywords: databases, 3D GIS, geotechnical monitoring, pipelines, laser scaning
Procedia PDF Downloads 189135 Stochastic Nuisance Flood Risk for Coastal Areas
Authors: Eva L. Suarez, Daniel E. Meeroff, Yan Yong
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The U.S. Federal Emergency Management Agency (FEMA) developed flood maps based on experts’ experience and estimates of the probability of flooding. Current flood-risk models evaluate flood risk with regional and subjective measures without impact from torrential rain and nuisance flooding at the neighborhood level. Nuisance flooding occurs in small areas in the community, where a few streets or blocks are routinely impacted. This type of flooding event occurs when torrential rainstorm combined with high tide and sea level rise temporarily exceeds a given threshold. In South Florida, this threshold is 1.7 ft above Mean Higher High Water (MHHW). The National Weather Service defines torrential rain as rain deposition at a rate greater than 0.3-inches per hour or three inches in a single day. Data from the Florida Climate Center, 1970 to 2020, shows 371 events with more than 3-inches of rain in a day in 612 months. The purpose of this research is to develop a data-driven method to determine comprehensive analytical damage-avoidance criteria that account for nuisance flood events at the single-family home level. The method developed uses the Failure Mode and Effect Analysis (FMEA) method from the American Society of Quality (ASQ) to estimate the Damage Avoidance (DA) preparation for a 1-day 100-year storm. The Consequence of Nuisance Flooding (CoNF) is estimated from community mitigation efforts to prevent nuisance flooding damage. The Probability of Nuisance Flooding (PoNF) is derived from the frequency and duration of torrential rainfall causing delays and community disruptions to daily transportation, human illnesses, and property damage. Urbanization and population changes are related to the U.S. Census Bureau's annual population estimates. Data collected by the United States Department of Agriculture (USDA) Natural Resources Conservation Service’s National Resources Inventory (NRI) and locally by the South Florida Water Management District (SFWMD) track the development and land use/land cover changes with time. The intent is to include temporal trends in population density growth and the impact on land development. Results from this investigation provide the risk of nuisance flooding as a function of CoNF and PoNF for coastal areas of South Florida. The data-based criterion provides awareness to local municipalities on their flood-risk assessment and gives insight into flood management actions and watershed development.Keywords: flood risk, nuisance flooding, urban flooding, FMEA
Procedia PDF Downloads 98134 Freshwater Pinch Analysis for Optimal Design of the Photovoltaic Powered-Pumping System
Authors: Iman Janghorban Esfahani
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Due to the increased use of irrigation in agriculture, the importance and need for highly reliable water pumping systems have significantly increased. The pumping of the groundwater is essential to provide water for both drip and furrow irrigation to increase the agricultural yield, especially in arid regions that suffer from scarcities of surface water. The most common irrigation pumping systems (IPS) consume conventional energies through the use of electric motors and generators or connecting to the electricity grid. Due to the shortage and transportation difficulties of fossil fuels, and unreliable access to the electricity grid, especially in the rural areas, and the adverse environmental impacts of fossil fuel usage, such as greenhouse gas (GHG) emissions, the need for renewable energy sources such as photovoltaic systems (PVS) as an alternative way of powering irrigation pumping systems is urgent. Integration of the photovoltaic systems with irrigation pumping systems as the Photovoltaic Powered-Irrigation Pumping System (PVP-IPS) can avoid fossil fuel dependency and the subsequent greenhouse gas emissions, as well as ultimately lower energy costs and improve efficiency, which made PVP-IPS systems as an environmentally and economically efficient solution for agriculture irrigation in every region. The greatest problem faced by integration of PVP with IPS systems is matching the intermittence of the energy supply with the dynamic water demand. The best solution to overcome the intermittence is to incorporate a storage system into the PVP-IPS to provide water-on-demand as a highly reliable stand-alone irrigation pumping system. The water storage tank (WST) is the most common storage device for PVP-IPS systems. In the integrated PVP-IPS with a water storage tank (PVP-IPS-WST), a water storage tank stores the water pumped by the IPS in excess of the water demand and then delivers it when demands are high. The Freshwater pinch analysis (FWaPA) as an alternative to mathematical modeling was used by other researchers for retrofitting the off-grid battery less photovoltaic-powered reverse osmosis system. However, the Freshwater pinch analysis has not been used to integrate the photovoltaic systems with irrigation pumping system with water storage tanks. In this study, FWaPA graphical and numerical tools were used for retrofitting an existing PVP-IPS system located in Salahadin, Republic of Iraq. The plant includes a 5 kW submersible water pump and 7.5 kW solar PV system. The Freshwater Composite Curve as the graphical tool and Freashwater Storage Cascade Table as the numerical tool were constructed to determine the minimum required outsourced water during operation, optimal amount of delivered electricity to the water pump, and optimal size of the water storage tank for one-year operation data. The results of implementing the FWaPA on the case study show that the PVP-IPS system with a WST as the reliable system can reduce outsourced water by 95.41% compare to the PVP-IPS system without storage tank.Keywords: irrigation, photovoltaic, pinch analysis, pumping, solar energy
Procedia PDF Downloads 138133 Understanding Project Failures in Construction: The Critical Impact of Financial Capacity
Authors: Nnadi Ezekiel Oluwaseun Ejiofor
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This research investigates the effects of poor cost estimation, material cost variations, and payment punctuality on the financial health and execution of construction projects in Nigeria. To achieve the objectives of the study, a quantitative research approach was employed, and data was gathered through an online survey of 74 construction industry professionals consisting of quantity surveyors, contractors, and other professionals. The study surveyed input on cost estimation errors, price fluctuations, and payment delays, among other factors. The responses of the respondents were analyzed using a five-point Likert scale and the Relative Importance Index (RII). The findings demonstrated that the errors in cost estimating in the Bill of Quantity (BOQ) have a high degree of negative impact on the reputation and image of the participants in the projects. The greatest effect was experienced on the likelihood of obtaining future endeavors for contractors (mean value = 3.42), followed by the likelihood of obtaining new commissions by quantity surveyors (mean value = 3.40). The level of inaccuracy in costing that undershoots exposes them to risks was most serious in terms of easement of construction and effects of shortage of funds to pursue bankruptcy (hence fears of mean value = 3.78). There was also considerable financial damage as a result of cost underestimation, whereby contractors suffered the worst loss in profit (mean value = 3.88). Every expense comes with its own peculiar risk and uncertainty. Pressure on the cost of materials and every other expense attributed to the building and completion of a structure adds risks to the performance figures of a project. The greatest weight (mean importance score = 4.92) was attributed to issues like market inflation in building materials, while the second greatest weight (mean importance score = 4.76) was due to increased transportation charges. On the other hand, delays in payments arising from issues of the clients like poor availability of funds (RII=0.71) and contracting issues such as disagreements on the valuation of works done (RII=0.72) or other reasons were also found to lead to project delays and additional costs. The results affirm the importance of proper cost estimation on the health of organization finances and project risks and finishes within set time limits. As for the suggestions, it is proposed to progress on the methods of costing, engender better communications with the stakeholders, and manage the delays by way of contracting and financial control. This study enhances the existing literature on construction project management by suggesting ways to deal with adverse cost inaccuracies and availability of materials due to delays in payments which, if addressed, would greatly improve the economic performance of the construction business.Keywords: cost estimation, construction project management, material price fluctuations, payment delays, financial impact
Procedia PDF Downloads 8132 Exploring the Physical Activity Behavior and Needs of Adolescent Girls: A Mixed-Methods Study
Authors: Vicki R. Voskuil, Jorgie M. Watson
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Despite the well-established health benefits of physical activity (PA), most adolescents do not meet guidelines recommending 60 minutes of moderate to vigorous physical activity (MVPA) each day. Adolescent girls engage in less PA than boys, a difference that increases with age. By the 9th grade, only 20% of girls report meeting recommendations for PA with lower percentages for black and Hispanic girls compared to white girls. The purpose of the study was to explore the physical activity (PA) behavior and needs of adolescent girls. Study aims included assessment of adolescent girls’ PA behavior; facilitators of and barriers to PA, PA needs, and acceptability of the Fitbit-Flex 2 activity tracker. This exploratory study used a qualitative and quantitative approach. The qualitative approach involved a focus group using a semi-structured interview technique. PA was measured using the Fitbit-Flex 2 activity tracker. Steps, distance, and active minutes were recorded for one week. A Fitbit survey was also administered to assess acceptability. SPSS Version 22.0 and ATLAS.ti Version 8 were used to analyze data. Girls in the ninth grade were recruited from a high school in the Midwest (n=11). Girls were excluded if they were involved in sports or other organized PA ≥ 3 days per week, had a health condition that prevented or limited PA, or could not read and write English. Participants received a Fitbit-Flex 2 activity tracker to wear for one week. At the end of the week, girls returned the Fitbit and participated in a focus group. Girls responded to open-ended questions regarding their PA behavior and shared their ideas for future intervention efforts aimed at increasing PA among adolescents. Girls completed a survey assessing their perceptions of the Fitbit. Mean age of the girls was 15.3 years (SD=0.44). On average girls took 6,520 steps and walked 2.73 miles each day. Girls stated their favorite types of PA were walking, riding bike, and running. Most girls stated they did PA for 30 minutes or more at a time once a day or every other day. The top 3 facilitators of PA reported by girls were friends, family, and transportation. The top 3 barriers included health issues, lack of motivation, and weather. Top intervention ideas were community service projects, camps, and using a Fitbit activity tracker. Girls felt the best timing of a PA program would be in the summer. Fitbit survey results showed 100% of girls would use a Fitbit on most days if they had one. Ten (91%) girls wore the Fitbit on all days. Seven (64%) girls used the Fitbit app and all reported they liked it. Findings indicate that PA participation for this sample is consistent with previous studies. Adolescent girls are not meeting recommended daily guidelines for PA. Fitbit activity trackers were positively received by all participants and could be used in future interventions aimed at increasing PA for adolescent girls. PA interventions that take place in the summer with friends and include community service projects may increase PA and be well received by this population.Keywords: adolescents, girls, interventions, physical activity
Procedia PDF Downloads 228131 A Multimodal Discourse Analysis of Gender Representation on Health and Fitness Magazine Cover Pages
Authors: Nashwa Elyamany
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In visual cultures, namely that of the United States, media representations are such influential and pervasive reflections of societal norms and expectations to the extent that they impact the manner in which both genders view themselves. Health and fitness magazines fall within the realm of visual culture. Since the main goal of communication is to ensure proper dissemination of information in order for the target audience to grasp the intended messages, it becomes imperative that magazine publishers, editors, advertisers and image producers use different modes of communication within their reach to convey messages to their readers and viewers. A rapid waxing flow of multimodality floods popular discourse, particularly health and fitness magazine cover pages. The use of well-crafted cover lines and visual images is imbued with agendas, consumerist ideologies and properties capable of effectively conveying implicit and explicit meaning to potential readers and viewers. In essence, the primary goal of this thesis is to interrogate the multi-semiotic operations and manifestations of hegemonic masculinity and femininity in male and female body culture, particularly on the cover pages of the twin American magazines Men's Health and Women's Health using corpora that spanned from 2011 to the mid of 2016. The researcher explores the semiotic resources that contribute to shaping and legitimizing a new form of postmodern, consumerist, gendered discourse that positions the reader-viewer ideologically. Methodologically, the researcher carries out analysis on the macro and micro levels. On the macro level, the researcher takes on a critical stance to illuminate the ideological nature of the multimodal ensemble of the cover pages, and, on the micro level, seeks to put forward new theoretical and methodological routes through which the semiotic choices well invested on the media texts can be more objectively scrutinized. On the macro level, a 'themes' analysis is initially conducted to isolate the overarching themes that dominate the fitness discourse on the cover pages under study. It is argued that variation in terms of frequencies of such themes is indicative, broadly speaking, of which facets of hegemonic masculinity and femininity are infused in the fitness discourse on the cover pages. On the micro level, this research work encompasses three sub-levels of analysis. The researcher follows an SF-MMDA approach, drawing on a trio of analytical frameworks: Halliday's SFG for the verbal analysis; Kress & van Leeuween's VG for the visual analysis; and CMT in relation to Sperber & Wilson's RT for the pragma-cognitive analysis of multimodal metaphors and metonymies. The data is presented in terms of detailed descriptions in conjunction with frequency tables, ANOVA with alpha=0.05 and MANOVA in the multiple phases of analysis. Insights and findings from this multi-faceted, social-semiotic analysis are interpreted in light of Cultivation Theory, Self-objectification Theory and the literature to date. Implications for future research include the implementation of a multi-dimensional approach whereby linguistic and visual analytical models are deployed with special regards to cultural variation.Keywords: gender, hegemony, magazine cover page, multimodal discourse analysis, multimodal metaphor, multimodal metonymy, systemic functional grammar, visual grammar
Procedia PDF Downloads 349130 Challenges of Blockchain Applications in the Supply Chain Industry: A Regulatory Perspective
Authors: Pardis Moslemzadeh Tehrani
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Due to the emergence of blockchain technology and the benefits of cryptocurrencies, intelligent or smart contracts are gaining traction. Artificial intelligence (AI) is transforming our lives, and it is being embraced by a wide range of sectors. Smart contracts, which are at the heart of blockchains, incorporate AI characteristics. Such contracts are referred to as "smart" contracts because of the underlying technology that allows contracting parties to agree on terms expressed in computer code that defines machine-readable instructions for computers to follow under specific situations. The transmission happens automatically if the conditions are met. Initially utilised for financial transactions, blockchain applications have since expanded to include the financial, insurance, and medical sectors, as well as supply networks. Raw material acquisition by suppliers, design, and fabrication by manufacturers, delivery of final products to consumers, and even post-sales logistics assistance are all part of supply chains. Many issues are linked with managing supply chains from the planning and coordination stages, which can be implemented in a smart contract in a blockchain due to their complexity. Manufacturing delays and limited third-party amounts of product components have raised concerns about the integrity and accountability of supply chains for food and pharmaceutical items. Other concerns include regulatory compliance in multiple jurisdictions and transportation circumstances (for instance, many products must be kept in temperature-controlled environments to ensure their effectiveness). Products are handled by several providers before reaching customers in modern economic systems. Information is sent between suppliers, shippers, distributors, and retailers at every stage of the production and distribution process. Information travels more effectively when individuals are eliminated from the equation. The usage of blockchain technology could be a viable solution to these coordination issues. In blockchains, smart contracts allow for the rapid transmission of production data, logistical data, inventory levels, and sales data. This research investigates the legal and technical advantages and disadvantages of AI-blockchain technology in the supply chain business. It aims to uncover the applicable legal problems and barriers to the use of AI-blockchain technology to supply chains, particularly in the food industry. It also discusses the essential legal and technological issues and impediments to supply chain implementation for stakeholders, as well as methods for overcoming them before releasing the technology to clients. Because there has been little research done on this topic, it is difficult for industrial stakeholders to grasp how blockchain technology could be used in their respective operations. As a result, the focus of this research will be on building advanced and complex contractual terms in supply chain smart contracts on blockchains to cover all unforeseen supply chain challenges.Keywords: blockchain, supply chain, IoT, smart contract
Procedia PDF Downloads 126129 Outputs from the Implementation of 'PHILOS' Programme: Emergency Health Response to Refugee Crisis, Greece, 2017
Authors: K. Mellou, G. Anastopoulos, T. Zakinthinos, C. Botsi, A. Terzidis
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‘PHILOS – Emergency health response to refugee crisis’ is a programme of the Greek Ministry of Health, implemented by the Hellenic Center for Disease Control and Prevention (HCDCP). The programme is funded by the Asylum, Migration and Integration Fund (AMIF) of EU’s DG Migration and Home Affairs. With the EU Member States accepting, the last period, accelerating migration flows, Greece inevitably occupies a prominent position in the migratory map due to this geographical location. The main objectives of the programme are a) reinforcement of the capacity of the public health system and enhancement of the epidemiological surveillance in order to cover refugees/migrant population, b) provision of on-site primary health care and psychological support services, and c) strengthening of national health care system task-force. The basic methods for achieving the aforementioned goals are: a) implementation of syndromic surveillance system at camps and enhancement of public health response with the use of mobile medical units (Sub-action A), b) enhancement of health care services inside the camps via increasing human resources and implementing standard operating procedures (Sub-action B), and c) reinforcement of the national health care system (primary healthcare units, hospitals, and emergency care spots) of affected regions with personnel (Sub-action C). As a result, 58 health professionals were recruited under sub-action 2 and 10 mobile unit teams (one or two at each health region) were formed. The main actions taken so far by the mobile units are the evaluation, of syndromic surveillance, of living conditions at camps and medical services. Also, vaccination coverage of children population was assessed, and more than 600 catch-up vaccinations were performed by the end of June 2017. Mobile units supported transportation of refugees/migrants from camps to medical services reducing the load of the National Center for Emergency Care (more than 350 transportations performed). The total number of health professionals (MD, nurses, etc.) placed at camps was 104. Common practices were implemented in the recording and collection of psychological and medical history forms at the camps. Protocols regarding maternity care, gender based violence and handling of violent incidents were produced and distributed at personnel working at camps. Finally, 290 health care professionals were placed at primary healthcare units, public hospitals and the National Center for Emergency Care at affected regions. The program has, also, supported training activities inside the camps and resulted to better coordination of offered services on site.Keywords: migrants, refugees, public health, syndromic surveillance, national health care system, primary care, emergency health response
Procedia PDF Downloads 206128 Distribution and Ecological Risk Assessment of Trace Elements in Sediments along the Ganges River Estuary, India
Authors: Priyanka Mondal, Santosh K. Sarkar
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The present study investigated the spatiotemporal distribution and ecological risk assessment of trace elements of surface sediments (top 0 - 5 cm; grain size ≤ 0.63 µm) in relevance to sediment quality characteristics along the Ganges River Estuary, India. Sediment samples were collected during ebb tide from intertidal regions covering seven sampling sites of diverse environmental stresses. The elements were analyzed with the help of ICPAES. This positive, mixohaline, macro-tidal estuary has global significance contributing ecological and economic services. Presence of fine-clayey particle (47.03%) enhances the adsorption as well as transportation of trace elements. There is a remarkable inter-metallic variation (mg kg-1 dry weight) in the distribution pattern in the following manner: Al (31801± 15943) > Fe (23337± 7584) > Mn (461±147) > S(381±235) > Zn(54 ±18) > V(43 ±14) > Cr(39 ±15) > As (34±15) > Cu(27 ±11) > Ni (24 ±9) > Se (17 ±8) > Co(11 ±3) > Mo(10 ± 2) > Hg(0.02 ±0.01). An overall trend of enrichment of majority of trace elements was very much pronounced at the site Lot 8, ~ 35km upstream of the estuarine mouth. In contrast, the minimum concentration was recorded at site Gangasagar, mouth of the estuary, with high energy profile. The prevalent variations in trace element distribution are being liable for a set of cumulative factors such as hydrodynamic conditions, sediment dispersion pattern and textural variations as well as non-homogenous input of contaminants from point and non-point sources. In order to gain insight into the trace elements distribution, accumulation, and their pollution status, geoaccumulation index (Igeo) and enrichment factor (EF) were used. The Igeo indicated that surface sediments were moderately polluted with As (0.60) and Mo (1.30) and strongly contaminated with Se (4.0). The EF indicated severe pollution of Se (53.82) and significant pollution of As (4.05) and Mo (6.0) and indicated the influx of As, Mo and Se in sediments from anthropogenic sources (such as industrial and municipal sewage, atmospheric deposition, agricultural run-off, etc.). The significant role of the megacity Calcutta in relevance to the untreated sewage discharge, atmospheric inputs and other anthropogenic activities is worthwhile to mention. The ecological risk for different trace elements was evaluated using sediment quality guidelines, effects range low (ERL), and effect range median (ERM). The concentration of As, Cu and Ni at 100%, 43% and 86% of the sampling sites has exceeded the ERL value while none of the element concentration exceeded ERM. The potential ecological risk index values revealed that As at 14.3% of the sampling sites would pose relatively moderate risk to benthic organisms. The effective role of finer clay particles for trace element distribution was revealed by multivariate analysis. The authors strongly recommend regular monitoring emphasizing on accurate appraisal of the potential risk of trace elements for effective and sustainable management of this estuarine environment.Keywords: pollution assessment, sediment contamination, sediment quality, trace elements
Procedia PDF Downloads 257127 Students’ Opinions Related to Virtual Classrooms within the Online Distance Education Graduate Program
Authors: Secil Kaya Gulen
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Face to face and virtual classrooms that came up with different conditions and environments, but similar purposes have different characteristics. Although virtual classrooms have some similar facilities with face-to-face classes such as program, students, and administrators, they have no walls and corridors. Therefore, students can attend the courses from a distance and can control their own learning spaces. Virtual classrooms defined as simultaneous online environments where students in different places come together at the same time with the guidance of a teacher. Distance education and virtual classes require different intellectual and managerial skills and models. Therefore, for effective use of virtual classrooms, the virtual property should be taken into consideration. One of the most important factors that affect the spread and effective use of the virtual classrooms is the perceptions and opinions of students -as one the main participants-. Student opinions and recommendations are important in terms of providing information about the fulfillment of expectation. This will help to improve the applications and contribute to the more efficient implementations. In this context, ideas and perceptions of the students related to the virtual classrooms, in general, were determined in this study. Advantages and disadvantages of virtual classrooms expected contributions to the educational system and expected characteristics of virtual classrooms have examined in this study. Students of an online distance education graduate program in which all the courses offered by virtual classrooms have asked for their opinions. Online Distance Education Graduate Program has totally 19 students. The questionnaire that consists of open-ended and multiple choice questions sent to these 19 students and finally 12 of them answered the questionnaire. Analysis of the data presented as frequencies and percentages for each item. SPSS for multiple-choice questions and Nvivo for open-ended questions were used for analyses. According to the results obtained by the analysis, participants stated that they did not get any training on virtual classes before the courses; but they emphasize that newly enrolled students should be educated about the virtual classrooms. In addition, all participants mentioned that virtual classroom contribute their personal development and they want to improve their skills by gaining more experience. The participants, who mainly emphasize the advantages of virtual classrooms, express that the dissemination of virtual classrooms will contribute to the Turkish Education System. Within the advantages of virtual classrooms, ‘recordable and repeatable lessons’ and ‘eliminating the access and transportation costs’ are most common advantages according to the participants. On the other hand, they mentioned ‘technological features and keyboard usage skills affect the attendance’ is the most common disadvantage. Participants' most obvious problem during virtual lectures is ‘lack of technical support’. Finally ‘easy to use’, ‘support possibilities’, ‘communication level’ and ‘flexibility’ come to the forefront in the scope of expected features of virtual classrooms. Last of all, students' opinions about the virtual classrooms seems to be generally positive. Designing and managing virtual classrooms according to the prioritized features will increase the students’ satisfaction and will contribute to improve applications that are more effective.Keywords: distance education, virtual classrooms, higher education, e-learning
Procedia PDF Downloads 269126 Large Scale Method to Assess the Seismic Vulnerability of Heritage Buidings: Modal Updating of Numerical Models and Vulnerability Curves
Authors: Claire Limoge Schraen, Philippe Gueguen, Cedric Giry, Cedric Desprez, Frédéric Ragueneau
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Mediterranean area is characterized by numerous monumental or vernacular masonry structures illustrating old ways of build and live. Those precious buildings are often poorly documented, present complex shapes and loadings, and are protected by the States, leading to legal constraints. This area also presents a moderate to high seismic activity. Even moderate earthquakes can be magnified by local site effects and cause collapse or significant damage. Moreover the structural resistance of masonry buildings, especially when less famous or located in rural zones has been generally lowered by many factors: poor maintenance, unsuitable restoration, ambient pollution, previous earthquakes. Recent earthquakes prove that any damage to these architectural witnesses to our past is irreversible, leading to the necessity of acting preventively. This means providing preventive assessments for hundreds of structures with no or few documents. In this context we want to propose a general method, based on hierarchized numerical models, to provide preliminary structural diagnoses at a regional scale, indicating whether more precise investigations and models are necessary for each building. To this aim, we adapt different tools, being developed such as photogrammetry or to be created such as a preprocessor starting from pictures to build meshes for a FEM software, in order to allow dynamic studies of the buildings of the panel. We made an inventory of 198 baroque chapels and churches situated in the French Alps. Then their structural characteristics have been determined thanks field surveys and the MicMac photogrammetric software. Using structural criteria, we determined eight types of churches and seven types for chapels. We studied their dynamical behavior thanks to CAST3M, using EC8 spectrum and accelerogramms of the studied zone. This allowed us quantifying the effect of the needed simplifications in the most sensitive zones and choosing the most effective ones. We also proposed threshold criteria based on the observed damages visible in the in situ surveys, old pictures and Italian code. They are relevant in linear models. To validate the structural types, we made a vibratory measures campaign using vibratory ambient noise and velocimeters. It also allowed us validating this method on old masonry and identifying the modal characteristics of 20 churches. Then we proceeded to a dynamic identification between numerical and experimental modes. So we updated the linear models thanks to material and geometrical parameters, often unknown because of the complexity of the structures and materials. The numerically optimized values have been verified thanks to the measures we made on the masonry components in situ and in laboratory. We are now working on non-linear models redistributing the strains. So we validate the damage threshold criteria which we use to compute the vulnerability curves of each defined structural type. Our actual results show a good correlation between experimental and numerical data, validating the final modeling simplifications and the global method. We now plan to use non-linear analysis in the critical zones in order to test reinforcement solutions.Keywords: heritage structures, masonry numerical modeling, seismic vulnerability assessment, vibratory measure
Procedia PDF Downloads 492125 Urban Design as a Tool in Disaster Resilience and Urban Hazard Mitigation: Case of Cochin, Kerala, India
Authors: Vinu Elias Jacob, Manoj Kumar Kini
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Disasters of all types are occurring more frequently and are becoming more costly than ever due to various manmade factors including climate change. A better utilisation of the concept of governance and management within disaster risk reduction is inevitable and of utmost importance. There is a need to explore the role of pre- and post-disaster public policies. The role of urban planning/design in shaping the opportunities of households, individuals and collectively the settlements for achieving recovery has to be explored. Governance strategies that can better support the integration of disaster risk reduction and management has to be examined. The main aim is to thereby build the resilience of individuals and communities and thus, the states too. Resilience is a term that is usually linked to the fields of disaster management and mitigation, but today has become an integral part of planning and design of cities. Disaster resilience broadly describes the ability of an individual or community to 'bounce back' from disaster impacts, through improved mitigation, preparedness, response, and recovery. The growing population of the world has resulted in the inflow and use of resources, creating a pressure on the various natural systems and inequity in the distribution of resources. This makes cities vulnerable to multiple attacks by both natural and man-made disasters. Each urban area needs elaborate studies and study based strategies to proceed in the discussed direction. Cochin in Kerala is the fastest and largest growing city with a population of more than 26 lakhs. The main concern that has been looked into in this paper is making cities resilient by designing a framework of strategies based on urban design principles for an immediate response system especially focussing on the city of Cochin, Kerala, India. The paper discusses, understanding the spatial transformations due to disasters and the role of spatial planning in the context of significant disasters. The paper also aims in developing a model taking into consideration of various factors such as land use, open spaces, transportation networks, physical and social infrastructure, building design, and density and ecology that can be implemented in any city of any context. Guidelines are made for the smooth evacuation of people through hassle-free transport networks, protecting vulnerable areas in the city, providing adequate open spaces for shelters and gatherings, making available basic amenities to affected population within reachable distance, etc. by using the tool of urban design. Strategies at the city level and neighbourhood level have been developed with inferences from vulnerability analysis and case studies.Keywords: disaster management, resilience, spatial planning, spatial transformations
Procedia PDF Downloads 296124 Development a Forecasting System and Reliable Sensors for River Bed Degradation and Bridge Pier Scouring
Authors: Fong-Zuo Lee, Jihn-Sung Lai, Yung-Bin Lin, Xiaoqin Liu, Kuo-Chun Chang, Zhi-Xian Yang, Wen-Dar Guo, Jian-Hao Hong
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In recent years, climate change is a major factor to increase rainfall intensity and extreme rainfall frequency. The increased rainfall intensity and extreme rainfall frequency will increase the probability of flash flood with abundant sediment transport in a river basin. The floods caused by heavy rainfall may cause damages to the bridge, embankment, hydraulic works, and the other disasters. Therefore, the foundation scouring of bridge pier, embankment and spur dike caused by floods has been a severe problem in the worldwide. This severe problem has happened in many East Asian countries such as Taiwan and Japan because of these areas are suffered in typhoons, earthquakes, and flood events every year. Results from the complex interaction between fluid flow patterns caused by hydraulic works and the sediment transportation leading to the formation of river morphology, it is extremely difficult to develop a reliable and durable sensor to measure river bed degradation and bridge pier scouring. Therefore, an innovative scour monitoring sensor using vibration-based Micro-Electro Mechanical Systems (MEMS) was developed. This vibration-based MEMS sensor was packaged inside a stainless sphere with the proper protection of the full-filled resin, which can measure free vibration signals to detect scouring/deposition processes at the bridge pier. In addition, a friendly operational system includes rainfall runoff model, one-dimensional and two-dimensional numerical model, and the applicability of sediment transport equation and local scour formulas of bridge pier are included in this research. The friendly operational system carries out the simulation results of flood events that includes the elevation changes of river bed erosion near the specified bridge pier and the erosion depth around bridge piers. In addition, the system is developed with easy operation and integrated interface, the system can supplies users to calibrate and verify numerical model and display simulation results through the interface comparing to the scour monitoring sensors. To achieve the forecast of the erosion depth of river bed and main bridge pier in the study area, the system also connects the rainfall forecast data from Taiwan Typhoon and Flood Research Institute. The results can be provided available information for the management unit of river and bridge engineering in advance.Keywords: flash flood, river bed degradation, bridge pier scouring, a friendly operational system
Procedia PDF Downloads 191123 Vertical Village Buildings as Sustainable Strategy to Re-Attract Mega-Cities in Developing Countries
Authors: M. J. Eichner, Y. S. Sarhan
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Overall study purpose has been the evaluation of ‘Vertical Villages’ as a new sustainable building typology, reducing significantly negative impacts of rapid urbanization processes in third world capital cities. Commonly in fast-growing cities, housing and job supply, educational and recreational opportunities, as well as public transportation infrastructure, are not accommodating rapid population growth, exposing people to high noise and emission polluted living environments with low-quality neighborhoods and a lack of recreational areas. Like many others, Egypt’s capital city Cairo, according to the UN facing annual population growth rates of up to 428.000 people, is struggling to address the general deterioration of urban living conditions. New settlements typologies and urban reconstruction approach hardly follow sustainable urbanization principles or socio-ecologic urbanization models with severe effects not only for inhabitants but also for the local environment and global climate. The authors prove that ‘Vertical Village’ buildings can offer a sustainable solution for increasing urban density with at the same time improving the living quality and urban environment significantly. Inserting them within high-density urban fabrics the ecologic and socio-cultural conditions of low-quality neighborhoods can be transformed towards districts, considering all needs of sustainable and social urban life. This study analyzes existing building typologies in Cairo’s «low quality - high density» districts Ard el Lewa, Dokki and Mohandesen according to benchmarks for sustainable residential buildings, identifying major problems and deficits. In 3 case study design projects, the sustainable transformation potential through ‘Vertical Village’ buildings are laid out and comparative studies show the improvement of the urban microclimate, safety, social diversity, sense of community, aesthetics, privacy, efficiency, healthiness and accessibility. The main result of the paper is that the disadvantages of density and overpopulation in developing countries can be converted with ‘Vertical Village’ buildings into advantages, achieving attractive and environmentally friendly living environments with multiple synergies. The paper is documenting based on scientific criteria that mixed-use vertical building structures, designed according to sustainable principles of low rise housing, can serve as an alternative to convert «low quality - high density» districts in megacities, opening a pathway for governments to achieve sustainable urban transformation goals. Neglected informal urban districts, home to millions of the poorer population groups, can be converted into healthier living and working environments.Keywords: sustainable, architecture, urbanization, urban transformation, vertical village
Procedia PDF Downloads 124122 Community Resilience in Response to the Population Growth in Al-Thahabiah Neighborhood
Authors: Layla Mujahed
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Amman, the capital of Jordan, is the main political, economic, social and cultural center of Jordan and beyond. The city faces multitude demographic challenges related to the unstable political situation in the surrounded countries. It has regional and local migrants who left their homes to find better life in the capital. This resulted with random and unequaled population distribution. Some districts have high population and pressure on the infrastructure and services more than other districts.Government works to resolve this challenge in compliance with 100 Cities Resilience Framework (CRF). Amman participated in this framework as a member in December 2014 to work in achieving the four goals: health and welfare, infrastructure and utilities, economy and education as well as administration and government. Previous research studies lack in studying Amman resilient work in neighborhood scale and the population growth as resilient challenge. For that, this study focuses on Al-Thahabiah neighborhood in Shafa Badran district in Amman. This paper studies the reasons and drivers behind this population growth during the selected period in this area then provide strategies to improve the resilient work in neighborhood scale. The methodology comprises of primary and secondary data. The primary data consist of interviews with chief officer in the executive part in Great Amman Municipality and resilient officer. The secondary data consist of papers, journals, newspaper, articles and book’s reading. The other part of data consists of maps and statistical data which describe the infrastructural and social situation in the neighborhood and district level during the studying period. Based upon those data, more detailed information will be found, e.g., the centralizing position of population and the provided infrastructure for them. This will help to provide these services and infrastructure to other neighborhoods and enhance population distribution. This study develops an analytical framework to assess urban demographical time series in accordance with the criteria of CRF to make accurate detailed projections on the requirements for the future development in the neighborhood scale and organize the human requirements for affordable quality housing, employment, transportation, health and education in this neighborhood to improve the social relations between its inhabitants and the community. This study highlights on the localization of resilient work in neighborhood scale and spread the resilient knowledge related to the shortage of its research in Jordan. Studying the resilient work from population growth challenge perspective helps improve the facilities provide to the inhabitants and improve their quality of life.Keywords: city resilience framework, demography, population growth, stakeholders, urban resilience
Procedia PDF Downloads 179121 Conceptual Design of Gravity Anchor Focusing on Anchor Towing and Lowering
Authors: Vinay Kumar Vanjakula, Frank Adam, Nils Goseberg
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Wind power is one of the leading renewable energy generation methods. Due to abundant higher wind speeds far away from shore, the construction of offshore wind turbines began in the last decades. However, installation of offshore foundation-based (monopiles) wind turbines in deep waters are often associated with technical and financial challenges. To overcome such challenges, the concept of floating wind turbines is expanded as the basis from the oil and gas industry. The unfolding of Universal heavyweight gravity anchor (UGA) for floating based foundation for floating Tension Leg Platform (TLP) sub-structures is developed in this research work. It is funded by the German Federal Ministry of Education and Research) for a three-year (2019-2022) research program called “Offshore Wind Solutions Plus (OWSplus) - Floating Offshore Wind Solutions Mecklenburg-Vorpommern.” It’s a group consists of German institutions (Universities, laboratories, and consulting companies). The part of the project is focused on the numerical modeling of gravity anchor that involves to analyze and solve fluid flow problems. Compared to gravity-based torpedo anchors, these UGA will be towed and lowered via controlled machines (tug boats) at lower speeds. This kind of installation of UGA are new to the offshore wind industry, particularly for TLP, and very few research works have been carried out in recent years. Conventional methods for transporting the anchor requires a large transportation crane vessel which involves a greater cost. This conceptual UGA anchors consists of ballasting chambers which utilizes the concept of buoyancy forces; the inside chambers are filled with the required amount of water in a way that they can float on the water for towing. After reaching the installation site, those chambers are ballasted with water for lowering. After it’s lifetime, these UGA can be unballasted (for erection or replacement) results in self-rising to the sea surface; buoyancy chambers give an advantage for using an UGA without the need of heavy machinery. However, while lowering/rising the UGA towards/away from the seabed, it experiences difficult, harsh marine environments due to the interaction of waves and currents. This leads to drifting of the anchor from the desired installation position and damage to the lowering machines. To overcome such harsh environments problems, a numerical model is built to investigate the influences of different outer contours and other fluid governing shapes that can be installed on the UGA to overcome the turbulence and drifting. The presentation will highlight the importance of the Computational Fluid Dynamics (CFD) numerical model in OpenFOAM, which is open-source programming software.Keywords: anchor lowering, towing, waves, currrents, computational fluid dynamics
Procedia PDF Downloads 166120 Zeolite 4A-confined Ni-Co Nanocluster: An Efficient and Durable Electrocatalyst for Alkaline Methanol Oxidation Reaction
Authors: Sarmistha Baruah, Akshai Kumar, Nageswara Rao Peela
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The global energy crisis due to the dependence on fossil fuels and its limited reserves as well as environmental pollution are key concerns to the research communities. However, the implementation of alcohol-based fuel cells such as methanol is anticipated as a reliable source of future energy technology due to their high energy density, environment friendliness, ease of storage, transportation, etc. To drive the anodic methanol oxidation reaction (MOR) in direct methanol fuel cells (DMFCs), an active and long-lasting catalyst is necessary for efficient energy conversion from methanol. Recently, transition metal-zeolite-based materials have been considered versatile catalysts for a variety of industrial and lab-scale processes. Large specific surface area, well-organized micropores, and adjustable acidity/basicity are characteristics of zeolites that make them excellent supports for immobilizing small-sized and highly dispersed metal species. Significant advancement in the production and characterization of well-defined metal clusters encapsulated within zeolite matrix has substantially expanded the library of materials available, and consequently, their catalytic efficacy. In this context, we developed bimetallic Ni-Co catalysts encapsulated within LTA (also known as 4A) zeolite via a method combined with the in-situ encapsulation of metal species using hydrothermal treatment followed by a chemical reduction process. The prepared catalyst was characterized using advanced characterization techniques, such as X-ray diffraction (XRD), field emission transmission electron microscope (FETEM), field emission scanning electron microscope (FESEM), energy dispersive X-ray (EDX), and X-ray photoelectron spectroscopy (XPS). The electrocatalytic activity of the catalyst for MOR was carried out in an alkaline medium at room temperature using techniques such as cyclic voltammetry (CV), and chronoamperometry (CA). The resulting catalyst exhibited better catalytic activity of 12.1 mA cm-2 at 1.12 V vs Ag/AgCl and retained remarkable stability (~77%) even after 1000 cycles CV test for the electro-oxidation of methanol in alkaline media without any significant microstructural changes. The high surface area, better Ni-Co species integration in the zeolite, and the ample amount of surface hydroxyl groups contribute to highly dispersed active sites and quick analyte diffusion, which provide notable MOR kinetics. Thus, this study will open up new possibilities to develop a noble metal-free zeolite-based electrocatalyst due to its simple synthesis steps, large-scale fabrication, improved stability, and efficient activity for DMFC application.Keywords: alkaline media, bimetallic, encapsulation, methanol oxidation reaction, LTA zeolite.
Procedia PDF Downloads 65119 Railway Composite Flooring Design: Numerical Simulation and Experimental Studies
Authors: O. Lopez, F. Pedro, A. Tadeu, J. Antonio, A. Coelho
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The future of the railway industry lies in the innovation of lighter, more efficient and more sustainable trains. Weight optimizations in railway vehicles allow reducing power consumption and CO₂ emissions, increasing the efficiency of the engines and the maximum speed reached. Additionally, they reduce wear of wheels and rails, increase the space available for passengers, etc. Among the various systems that integrate railway interiors, the flooring system is one which has greater impact both on passenger safety and comfort, as well as on the weight of the interior systems. Due to the high weight saving potential, relative high mechanical resistance, good acoustic and thermal performance, ease of modular design, cost-effectiveness and long life, the use of new sustainable composite materials and panels provide the latest innovations for competitive solutions in the development of flooring systems. However, one of the main drawbacks of the flooring systems is their relatively poor resistance to point loads. Point loads in railway interiors can be caused by passengers or by components fixed to the flooring system, such as seats and restraint systems, handrails, etc. In this way, they can originate higher fatigue solicitations under service loads or zones with high stress concentrations under exceptional loads (higher longitudinal, transverse and vertical accelerations), thus reducing its useful life. Therefore, to verify all the mechanical and functional requirements of the flooring systems, many physical prototypes would be created during the design phase, with all of the high costs associated with it. Nowadays, the use of virtual prototyping methods by computer-aided design (CAD) and computer-aided engineering (CAE) softwares allow validating a product before committing to making physical test prototypes. The scope of this work was to current computer tools and integrate the processes of innovation, development, and manufacturing to reduce the time from design to finished product and optimise the development of the product for higher levels of performance and reliability. In this case, the mechanical response of several sandwich panels with different cores, polystyrene foams, and composite corks, were assessed, to optimise the weight and the mechanical performance of a flooring solution for railways. Sandwich panels with aluminum face sheets were tested to characterise its mechanical performance and determine the polystyrene foam and cork properties when used as inner cores. Then, a railway flooring solution was fully modelled (including the elastomer pads to provide the required vibration isolation from the car body) and perform structural simulations using FEM analysis to comply all the technical product specifications for the supply of a flooring system. Zones with high stress concentrations are studied and tested. The influence of vibration modes on the comfort level and stability is discussed. The information obtained with the computer tools was then completed with several mechanical tests performed on some solutions, and on specific components. The results of the numerical simulations and experimental campaign carried out are presented in this paper. This research work was performed as part of the POCI-01-0247-FEDER-003474 (coMMUTe) Project funded by Portugal 2020 through COMPETE 2020.Keywords: cork agglomerate core, mechanical performance, numerical simulation, railway flooring system
Procedia PDF Downloads 179118 Socio-Cultural Factors Influencing Adherence to Anti-Retroviral Therapy among HIV Patients in a University Teaching Hospital in South-Western Nigeria
Authors: Okunola Oluseye Ademola
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The study investigated various socio-cultural factors influencing adherence to antiretroviral drugs among people living with HIV in a University Teaching Hospital in South-western Nigeria. The objectives are to examine the perception of people living with HIV/AIDS (PLWHA) of antiretroviral therapy (ART) in Obafemi Awolowo University Teaching Hospitals Complex, Ile-Ife, investigate the influence of socio-cultural factors on adherence of PLWHA to treatment regimen in the study area and assess the prevalence of adherence to ART among PLWHA in the study area. It was a cross-sectional where both qualitative and quantitative research methods were adopted. The participants were HIV diagnosed patients attending clinic at the Obafemi Awolowo University Teaching Hospitals Complex in Ile-Ife between the ages of 18 and 60 years. Also three healthcare delivery personnel working in the clinic were interviewed. Out of the 3007 patients receiving treatment, using Fischer’s formula of sampling technique, 336 patients living with HIV/AIDS were selected for the study. These participants had been on antiretroviral drugs for more than six months prior to the study and were selected using simple random sampling technique. Two focus group discussion sessions comprising of 10 male and 10 female living with HIV and currently on ART were conducted. These groups were purposively selected based on their being on ART for more than one year. Also in-depth interviews were conducted among three purposively selected healthcare givers (an experienced nurse, a doctor and a pharmacist) who are working in this clinic. All the participants were interviewed at the clinic on the various clinic days. Data were collected using a structured questionnaire, an interview guide and tape-recorder. The quantitative data were analysed using descriptive and inferential statistics. Content analysis was employed to analyse responses from IDI and FGD sessions. The findings from the study revealed a very positive perception to ART among PLWHA which was about 86.3% while the level of adherence to ART was 89.0% among the respondents. There was a very strong relationship between social and family supports and the degree of adherence to ART in the PLWHA. Nutrition, polygamy, difficulty in financing transportation fare to the clinic, unemployment, drug hawkers, religion, excuse duty from work and waking up very early were highlighted as socio-cultural barriers to adherence to ART. Fear of death, strong family support, religion belief, not seeking alternative treatment, absence of rituals and perceived improved health status were identified as very strong facilitators to adherence. The study concluded that to achieve a very optimal outcome in the management of HIV among PLWHA, various social and cultural contexts should be taken into consideration as this study was able to ascertain the influence of various socio-cultural factors militating and facilitating adherence to ART.Keywords: ART, HIV, PLWHA, socio-cultural
Procedia PDF Downloads 278