Search results for: spent wash
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 566

Search results for: spent wash

206 Evaluation of Security and Performance of Master Node Protocol in the Bitcoin Peer-To-Peer Network

Authors: Muntadher Sallal, Gareth Owenson, Mo Adda, Safa Shubbar

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Bitcoin is a digital currency based on a peer-to-peer network to propagate and verify transactions. Bitcoin is gaining wider adoption than any previous crypto-currency. However, the mechanism of peers randomly choosing logical neighbors without any knowledge about underlying physical topology can cause a delay overhead in information propagation, which makes the system vulnerable to double-spend attacks. Aiming at alleviating the propagation delay problem, this paper introduces proximity-aware extensions to the current Bitcoin protocol, named Master Node Based Clustering (MNBC). The ultimate purpose of the proposed protocol, that are based on how clusters are formulated and how nodes can define their membership, is to improve the information propagation delay in the Bitcoin network. In MNBC protocol, physical internet connectivity increases, as well as the number of hops between nodes, decreases through assigning nodes to be responsible for maintaining clusters based on physical internet proximity. We show, through simulations, that the proposed protocol defines better clustering structures that optimize the performance of the transaction propagation over the Bitcoin protocol. The evaluation of partition attacks in the MNBC protocol, as well as the Bitcoin network, was done in this paper. Evaluation results prove that even though the Bitcoin network is more resistant against the partitioning attack than the MNBC protocol, more resources are needed to be spent to split the network in the MNBC protocol, especially with a higher number of nodes.

Keywords: Bitcoin network, propagation delay, clustering, scalability

Procedia PDF Downloads 94
205 An Economic Analysis of Bottled Drinking Water Industry in India

Authors: Swadhin Mondal

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While safe drinking water is an effective defense against the infection of water borne diseases, a large number of populations suffering from these diseases do not have access to safe drinking water due inadequacy of supply. Private entrepreneurs entered this sector and made bottled drinking water available by supplying various kinds of bottled water. In this study we found that the bottled drinking water industry has experienced a spectacular growth over the past two decades and it has a huge growth potential because of rising demand for safe drinking. High profit margin (217 %) is the main attraction to the entrepreneur to invest in this industry. Health awareness, lack of safe drinking water facilities, rising income, urbanization, migration and rising trend in tourism industries are the major influencing factors of demand for bottled drinking water (BDW). This industry also partially fulfills the demand for drinking water. More than 2 percent of household’s demands were met by this industry and many more households (additional 4 percent) coping with BDW during water crisis. Poor households spend around 4 percent of their total monthly household’s consumption expenditure on BDW which may have an adverse impact on household because households could have spent this for purchasing other goods. Like other developed counties, a large section of Indian households are shifting from their traditional sources of water to BDW. However, there are some concerns about the quality of BDW. Many cases, BDW contains chemical toxins at more than permissible level that can be harmful for health. Hence, there is an urgent need for appropriate intervention to regulate price, reduce potential harm and improve the quality of water provided by this industry.

Keywords: drinking water, public health public failure, privatization, development, public policy

Procedia PDF Downloads 305
204 Dimension of Water Accessibility in the Southern Part of Niger State, Nigeria

Authors: Kudu Dangana, Pai H. Halilu, Osesienemo R. Asiribo-Sallau, Garba Inuwa Kuta

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The study examined the determinants of household water accessibility in Southern part of Niger State, Nigeria. Data for the study was obtained from primary and secondary sources using questionnaire, interview, personal observation and documents. 1,192 questionnaires were administered; sampling techniques adopted are combination of purposive, stratified and simple random. Purposive sampling technique was used to determine sample frame; sample unit was determined using stratified sampling method and simple random technique was used in administering questionnaires. The result was analyzed within the scope of “WHO” water accessibility indicators using descriptive statistics. Major sources of water in the area are well; hand and electric pump borehole and streams. These sources account for over 90% of household’s water. Average per capita water consumption in the area is 22 liters per day, while location efficiency of facilities revealed an average of 80 people per borehole. Household water accessibility is affected mainly by the factors of distances, time spent to obtain water, low income status of the majority of respondents to access modern water infrastructure, and to a lesser extent household size. Recommendations includes, all tiers of government to intensify efforts in providing water infrastructures and existing ones through budgetary provisions, and communities should organize fund raising bazaar, so as to raise fund to improve water infrastructures in the area.

Keywords: accessibility, determined, stratified, scope

Procedia PDF Downloads 362
203 Modelling Heat Transfer Characteristics in the Pasteurization Process of Medium Long Necked Bottled Beers

Authors: S. K. Fasogbon, O. E. Oguegbu

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Pasteurization is one of the most important steps in the preservation of beer products, which improves its shelf life by inactivating almost all the spoilage organisms present in it. However, there is no gain saying the fact that it is always difficult to determine the slowest heating zone, the temperature profile and pasteurization units inside bottled beer during pasteurization, hence there had been significant experimental and ANSYS fluent approaches on the problem. This work now developed Computational fluid dynamics model using COMSOL Multiphysics. The model was simulated to determine the slowest heating zone, temperature profile and pasteurization units inside the bottled beer during the pasteurization process. The results of the simulation were compared with the existing data in the literature. The results showed that, the location and size of the slowest heating zone is dependent on the time-temperature combination of each zone. The results also showed that the temperature profile of the bottled beer was found to be affected by the natural convection resulting from variation in density during pasteurization process and that the pasteurization unit increases with time subject to the temperature reached by the beer. Although the results of this work agreed with literatures in the aspects of slowest heating zone and temperature profiles, the results of pasteurization unit however did not agree. It was suspected that this must have been greatly affected by the bottle geometry, specific heat capacity and density of the beer in question. The work concludes that for effective pasteurization to be achieved, there is a need to optimize the spray water temperature and the time spent by the bottled product in each of the pasteurization zones.

Keywords: modeling, heat transfer, temperature profile, pasteurization process, bottled beer

Procedia PDF Downloads 183
202 A Case Study on the Census of Technological Capacities in Health Care in Rural Sanitary Institutions in South Cameroon

Authors: Doriane Micaela Andeme Bikoro, Samuel Fosso Wamba, Jean Robert Kala Kamdjoug

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Currently one of the leading fields in the market of technological innovation is digital health. In developed countries, this booming innovation is experiencing an exponential speed. We understand that in developed countries, e-health could also revolutionize the practice of medicine and therefore fill the many failures observed in medical care. Everything leads to believe that future technology is oriented towards the medical sector. The aim of this work is to explore at the same time the technological resources and the potential of health care based on new technologies; it is a case study in a rural area of Southern Cameroon. Among other things, we will make a census of the shortcomings and problems encountered, and we will propose various appropriate solutions. The work methodology used here is essentially qualitative. We used two qualitative data collection techniques, direct observation, and interviews. In fact, we spent two weeks in the field observing and conducting some semi-directive interviews with some of those responsible for these health structures. This study was conducted in three health facilities in the south of the country; including two health centers and a rural hospital. Many technological failures have been identified in the day-to-day management of these health facilities and especially in the administration of health care to patients. We note major problems such as the digital divide, the lack of qualified personnel, the state of isolation of this area. This is why various proposals are made to improve the health sector in Cameroon both technologically and medically.

Keywords: Cameroon, capacities, census, digital health, qualitative method, rural area

Procedia PDF Downloads 127
201 Challenges in the Characterization of Black Mass in the Recovery of Graphite from Spent Lithium Ion Batteries

Authors: Anna Vanderbruggen, Kai Bachmann, Martin Rudolph, Rodrigo Serna

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Recycling of lithium-ion batteries has attracted a lot of attention in recent years and focuses primarily on valuable metals such as cobalt, nickel, and lithium. Despite the growth in graphite consumption and the fact that it is classified as a critical raw material in the European Union, USA, and Australia, there is little work focusing on graphite recycling. Thus, graphite is usually considered waste in recycling treatments, where graphite particles are concentrated in the “black mass”, a fine fraction below 1mm, which also contains the foils and the active cathode particles such as LiCoO2 or LiNiMnCoO2. To characterize the material, various analytical methods are applied, including X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), Atomic Absorption Spectrometry (AAS), and SEM-based automated mineralogy. The latter consists of the combination of a scanning electron microscopy (SEM) image analysis and energy-dispersive X-ray spectroscopy (EDS). It is a powerful and well-known method for primary material characterization; however, it has not yet been applied to secondary material such as black mass, which is a challenging material to analyze due to fine alloy particles and to the lack of an existing dedicated database. The aim of this research is to characterize the black mass depending on the metals recycling process in order to understand the liberation mechanisms of the active particles from the foils and their effect on the graphite particle surfaces and to understand their impact on the subsequent graphite flotation. Three industrial processes were taken into account: purely mechanical, pyrolysis-mechanical, and mechanical-hydrometallurgy. In summary, this article explores various and common challenges for graphite and secondary material characterization.

Keywords: automated mineralogy, characterization, graphite, lithium ion battery, recycling

Procedia PDF Downloads 215
200 The Mediating Role of Psychological Factors in the Relationships Between Youth Problematic Internet and Subjective Well-Being

Authors: Dorit Olenik-Shemesh, Tali Heiman

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The rapid increase in the massive use of the internet in recent yearshas led to an increase in the prevalence of a phenomenon called 'Problematic Internet use' (PIU), an emerging, growing health problem, especially during adolescents, that poses a challenge for mental health research and practitioners. Problematic Internet use (PIU) is defined as an excessive overuse of the internet, including an inability to control time spent on the internet, cognitivepreoccupation with the Internet, and continued use in spite of the adverse consequences, which may lead to psychological, social, and academic difficulties in one's life and daily functioning. However, little is known about the nature of the nexusbetween PIU and subjective well-being among adolescents. The main purpose of the current study was to explore in depth the network of connections between PIU, sense of well-being, and fourpersonal-emotional factors (resilience, self-control, depressive mood, and loneliness) that may mediate these relationships. A total sample of 433 adolescents, 214 (49.4%) girls and 219 (50.6%) boys between the ages of 12–17 (mean = 14.9, SD = 2.16), completed self-reportquestionnaires relating to the study variables. In line with the hypothesis, analysis of a Structural Equation modeling (SEM) revealed the main following results: high levels of PIU predicted low levels of well-being among adolescents. In addition, low levels of resilience and high levels of depressivemood (together), as well as low levels of self control and high levels of depressivemood (together), as well as low levels of resilience and high levels of loneliness, mediated the relationships between PIU and well-being. In general, girls were found to be higher in PIU and inresilience than boys. The study results revealed specific implications for developing intervention programs for adolescents in the context of PIU; aiming at more balanced adjusted use of the Internet along withpreventingthe decrease in well being.

Keywords: probelmatic inetrent Use, well-being, adolescents, SEM model

Procedia PDF Downloads 144
199 Analysis of the Impact and Effectiveness of Government Funded Small-Scale Biogas Projects in Giyani Municipality, Limpopo

Authors: Lindiwe Ngcobo

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The aim of the study is to describe and understand the benefits and costs of having biogas digesters at both household and society level. On a household level, the purpose is to understand how rural households benefit from the biogas digesters, for example, by converting animal and human waste through biogas digesters, and at what costs the benefits are realized. At a societal level, the purpose is to understand the costs and benefits of biogas digesters relative to the situation of rural communities who do not have flush toilets and have no appropriate waste disposal services while they incur electricity costs. Multiple regression analysis was used to determine the effect of biogas digesters on electricity availability and waste management. The results showed that beneficiaries spent less on electricity using household waste, and also waste disposal costs were eliminated from household expenses. A move to biogas energy production can be beneficial to rural households. It is economically and environmentally friendly. Small-scale farmers need to be introduced to agricultural innovations that can assist them in producing nutritious crops at a low cost. This can be a good opportunity to start an agribusiness that focuses on organic crops. Extensions and training institutions have to play a part in supporting households to develop entrepreneurial skills. Cost-benefit analysis showed that the benefits of biogas exceed the costs of the biogas projects. This implies that this technology should be promoted in rural households. Government financial incentives must be put in place to motivate a generation of organic Agri-prenuers.

Keywords: Agri-prenuers, biogas digester, biogas energy, disposal costs

Procedia PDF Downloads 107
198 Avoiding Gas Hydrate Problems in Qatar Oil and Gas Industry: Environmentally Friendly Solvents for Gas Hydrate Inhibition

Authors: Nabila Mohamed, Santiago Aparicio, Bahman Tohidi, Mert Atilhan

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Qatar's one of the biggest problem in processing its natural resource, which is natural gas, is the often occurring blockage in the pipelines caused due to uncontrolled gas hydrate formation in the pipelines. Several millions of dollars are being spent at the process site to dehydrate the blockage safely by using chemical inhibitors. We aim to establish national database, which addresses the physical conditions that promotes Qatari natural gas to form gas hydrates in the pipelines. Moreover, we aim to design and test novel hydrate inhibitors that are suitable for Qatari natural gas and its processing facilities. From these perspectives we are aiming to provide more effective and sustainable reservoir utilization and processing of Qatari natural gas. In this work, we present the initial findings of a QNRF funded project, which deals with the natural gas hydrate formation characteristics of Qatari type gas in both experimental (PVTx) and computational (molecular simulations) methods. We present the data from the two fully automated apparatus: a gas hydrate autoclave and a rocking cell. Hydrate equilibrium curves including growth/dissociation conditions for multi-component systems for several gas mixtures that represent Qatari type natural gas with and without the presence of well known kinetic and thermodynamic hydrate inhibitors. Ionic liquids were designed and used for testing their inhibition performance and their DFT and molecular modeling simulation results were also obtained and compared with the experimental results. Results showed significant performance of ionic liquids with up to 0.5 % in volume with up to 2 to 4 0C inhibition at high pressures.

Keywords: gas hydrates, natural gas, ionic liquids, inhibition, thermodynamic inhibitors, kinetic inhibitors

Procedia PDF Downloads 1285
197 An Experimental Study on Greywater Reuse for Irrigating a Green Wall System

Authors: Mishadi Herath, Amin Talei, Andreas Hermawan, Clarina Chua

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Green walls are vegetated structures on building’s wall that are considered as part of sustainable urban design. They are proved to have many micro-climate benefits such as reduction in indoor temperature, noise attenuation, and improvement in air quality. On the other hand, several studies have also been conducted on potential reuse of greywater in urban water management. Greywater is relatively clean when compared to blackwater; therefore, this study was aimed to assess the potential reuse of it for irrigating a green wall system. In this study, the campus of Monash University Malaysia located in Selangor state was considered as the study site where total 48 samples of greywater were collected from 7 toilets hand-wash and 5 pantries during 3 months period. The samples were tested to characterize the quality of greywater in the study site and compare it with local standard for irrigation water. PH and concentration of heavy metals, nutrients, Total Suspended Solids (TSS), Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), total Coliform and E.coli were measured. Results showed that greywater could be directly used for irrigation with minimal treatment. Since the effluent of the system was supposed to be drained to stormwater drainage system, the effluent needed to meet certain quality requirement. Therefore, a biofiltration system was proposed to host the green wall plants and also treat the greywater (which is used as irrigation water) to the required level. To assess the performance of the proposed system, an experimental setup consisting of Polyvinyl Chloride (PVC) soil columns with sand-based filter media were prepared. Two different local creeper plants were chosen considering several factors including fast growth, low maintenance requirement, and aesthetic aspects. Three replicates of each plants were used to ensure the validity of the findings. The growth of creeping plants and their survivability was monitored for 6 months while monthly sampling and testing of effluent was conducted to evaluate effluent quality. An analysis was also conducted to estimate the potential cost and benefit of such system considering water and energy saving in the system. Results showed that the proposed system can work efficiently throughout a long period of time with minimal maintenance requirement. Moreover, the biofiltration-green wall system was found to be successful in reusing greywater as irrigating water while the effluent was meeting all the requirements for being drained to stormwater drainage system.

Keywords: biofiltration, green wall, greywater, sustainability

Procedia PDF Downloads 193
196 The Role of Physical Education and Fitness for Active Ageing

Authors: A. Lakshya

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The main aim of this paper is to interpret physical education for children from 5 to 18 years. Schools have the ability to promote positive mental health by developing physical education, which helps to build individual growth, goal setting, decision making, helps in muscular development, self-discipline, stresses relief, leadership qualities that can arise with new skills, prosocial behavior and problem-solving skills. But mostly the children at these early ages ought to hold the disorders as heart attack, diabetes and obesity disorders may increase in large number. The data of P.E has got a very least place, where children are with feeble minds and they acquired a state of inactiveness. Globally, 81% of adolescents aged 11-18 years were insufficiently physically active in the year 2016. Adolescent girls were less active than boys, with the percentage of 85% vs. 78% as well. A recent study of California schools found that students are sedentary most of the time during PE classes, with just four minutes of every half-hour spent in vigorous physical activity. Additionally, active PE time decreases with larger class sizes. Students in classes with more than forty-five students are half as active as students in smaller class sizes. The children in adolescence age they acquire more creative ideas hence they create new hairstyles, cooking styles and dressing styles. Instead, all the children are engaging themselves to TV (television) and video games. The development of physical quality not only improves students ’ physical fitness but is also conducive to the psychological development of the students. Physical education teaching should pay more attention to the training of physical quality in the future.

Keywords: physical education, prosocial behavior, leadership, goal setting

Procedia PDF Downloads 114
195 Engaging Women Entrepreneurs in School Adolescent Health Program to Ensure Menstrual Hygiene Management in Rural Bangladesh

Authors: Toslim Uddin Khan, Jesmin Akter, Mohiuddin Ahmed

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Menstrual hygiene management (MHM) and personal health-care practice is a critical issue to prevent morbidity and other reproductive health complications among adolescent girls in Bangladesh. Inadequate access to water, sanitation and hygiene (WASH) facilities lead to unhealthy MHM practices that resulted in poor reproductive health outcomes. It is evident from different studies that superstitions and misconception are more common in rural communities that limit young girls’ access to and understanding of the menstrual hygiene and self care practices. The state-of-the-art approach of Social Marketing Company (SMC) is proved to be instrumental in delivering reinforcing health messages, making public health and hygiene products available at the door steps of the community through community mobilization programs in rural Bangladesh. School health program is one of the flagship interventions of SMC to equip adolescent girls and boys with correct knowledge of health and hygiene practices among themselves, their families and peers. In Bangladeshi culture, adolescent girls often feel shy to ask fathers or male family members about buying sanitary napkin from local pharmacy and they seem to be reluctant to seek help regarding their menstrual problems. A recent study reveals that 48% adolescent girls are using sanitary napkins while majority of them are unaware of menstrual hygiene practices in Bangladesh. Under school adolescent program, SMC organizes health education sessions for adolescent girls from grade seven to ten using enter-educate approach with special focus on sexual and reproductive health and menstrual hygiene issues including delaying marriage and first pregnancy. In addition, 2500 rural women entrepreneurs branded as community sales agents are also involved in disseminating health messages and selling priority health products including sanitary napkin at the household level. These women entrepreneurs are serving as a source of sustainable supply of the sanitary napkins for the rural adolescent girls and thereby they are earning profit margins on the sales they make. A recent study on the impact of adolescent program activities reveals that majority (71%) of the school adolescent girls are currently using sanitary napkins. Health education equips and empowers adolescent girls with accurate knowledge about menstrual hygiene practices and self-care as well. Therefore, engagement of female entrepreneurs in school adolescent health program at the community level is one of the promising ways to improve menstrual hygiene practices leading to increased use of sanitary napkin in rural and semi-rural communities in Bangladesh.

Keywords: school adolescent program, social marketing, women entrepreneurs, menstrual hygiene management

Procedia PDF Downloads 162
194 The Digital Library and Its Influential Role in Developing the Establishment of the Grand Egyptian Museum

Authors: Haitham Magdy Hamad, Mohamed Ahmed Madkour

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The essential role of the digital library in developing museum display methods, recording ancient Egyptian antiquities, facilitating scientific research, and storing antiquities in the Grand Egyptian Museum, which helped and saved a lot of time and money spent to equip the Grand Egyptian Museum. The technology of digital libraries, linking it to ancient Egyptian antiquities and the latest results, which scientific research has reached in the field of libraries and its impact on many areas of tourism and antiquities. The research also aims to show the main role of the digital library and the Arab countries emulating European countries in digitizing libraries and recent developments in Egyptian libraries and their role in many areas of life and linking them to Egyptology. The research will also explain how the museum display methods will be developed in the Grand Egyptian Museum, and the recording of ancient Egyptian antiquities in order to facilitate the process of scientific research and methods of storing antiquities will also work to save time and effort for researchers. The research will also deal with lighting and its prominent role in the display in the interior design and coordination of the Grand Egyptian Museum, through which the unique artifacts and artifacts displayed can be displayed, and they can be used in a strong or simple form. Depending on the condition of the piece to be displayed. The research will also go to show the role of the digital library in how the Grand Egyptian Museum contains gathering areas and how to distribute spaces, guidance, information, reception, libraries, lecture halls, restaurants, cafeterias, shops, permanent and temporary galleries, and bathrooms.

Keywords: knowledge, library, culture, archaeology, grand Egyptian museum, numbering

Procedia PDF Downloads 54
193 System of System Decisions Framework for Cross-Border Railway Projects

Authors: Dimitrios J. Dimitriou, Maria F. Sartzetaki, Anastasia Kalamakidou

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Transport infrastructure assets are key components of the national asset portfolio. The decision to invest in a new infrastructure in transports could take from a few years to some decades. This is mainly because of the need to reserve and spent many capitals, the long payback period, the number of the stakeholders involved in the decision process and –many times- the investment and business risks are high. Decision makers and stakeholders need to define the framework and the outputs of the decision process taking into account the project characteristics, the business uncertainties, and the different expectations. Therefore, the decision assessment framework is an essential challenge linked with the key decision factors meet the stakeholder expectations highlighting project trade-offs, financial risks, business uncertainties and market limitations. This paper examines the decision process for new transport infrastructure projects in cross-border regions, where a wide range of stakeholders with different expectation is involved. According to a consequences analysis systemic approach, the relationship of transport infrastructure development, economic system development and stakeholder expectation is analysed. Adopting the on system of system methodological approach, the decision making the framework, variables, inputs and outputs are defined, highlighting the key shareholder’s role and expectations. The application provides the methodology outputs presenting the proposed decision framework for a strategic railway project in north Greece deals with the upgrade of the existing railway corridor connecting Greece, Turkey, and Bulgaria.

Keywords: system of system decision making, managing decisions for transport projects, decision support framework, defining decision process

Procedia PDF Downloads 280
192 Functional Finishing of Organic Cotton Fabric Using Vetiver Root Extract

Authors: Sakeena Naikwadi, K. Jagaluraiah Sannapapamma

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Vetiveria zizanioides is an aromatic grass and traditionally been used in aromatherapy and ayurvedic medicine. Vetiver root is multi-functional biopolymer and has highly aromatic, antimicrobial, UV blocking, antioxidant properties suitable for textile finishing. The vetiver root (Gulabi) powder of different concentration (2, 4, 6,8 percent) were extracted by aqueous and solvent methods subjected to bioassay for antimicrobial efficiency and GCMS spectral analysis. The organic cotton fabric was finished with vetiver root extract (8 percent) by exhaust and pad dry cure methods. The finished fabric was assessed for functional properties viz., UV protective factor, antimicrobial efficiency and aroma intensity. The results revealed that Ethanol extraction showed a greater zone of inhibition compared to aqueous extract in root powder. Among the concentrations, 8 percent root extract in ethanol showed a greater zone of inhibition against gram-positive organism S. aureus and gram-negative organism E. coli. The major compounds present in vetiver root extracts were diethyl pathalate with greater percentage (87.73 %) followed by 7- Isopropyl dimethyl carboxylic acid (4.05 %), 2-butanone 4-trimethyle cyclohexen (1.21 %), phenanthrene carboxylic acid (1.03 %), naphthalene pentanoic acid (0.99 %), 1-phenanthrene carboxylic acid and 1 cyclohexenone 2-methyl oxobuty (0.89 %). The sample finished by pad dry cure method exhibited better UV protection even after 10th wash as compared to exhaust method. Vetiver extract treated samples exhibited maximum zone of inhibition against S. aureus than the E. coli organism. The vetiver root extract treated organic cotton fabric through pad dry cure method possessed good antimicrobial activity against S. aureus and E. coli even after 20th washes compared to vetiver root extract treated by exhaust method. The olfactory analysis was carried out by 30 panels of members and opined that vetiver root extract treated fabric has very good and pleasant aroma with better tactile properties that provide cooling, soothing effect and enhances the mood of the wearer. Vetiver root extract finished organic cotton fabric possessed aroma, antimicrobial and UV properties which are aptly suitable for medical and healthcare textiles viz., wound dressing, bandage gauze, surgical cloths, baby diapers and sanitary napkins. It can be used as after finishing agent for variegated garments and made-ups and can be replaced with commercial after finishing agents.

Keywords: antimicrobial, olfactory analysis, UV protection factor, vetiver root extract

Procedia PDF Downloads 197
191 Adsorption of Heavy Metals Using Chemically-Modified Tea Leaves

Authors: Phillip Ahn, Bryan Kim

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Copper is perhaps the most prevalent heavy metal used in the manufacturing industries, from food additives to metal-mechanic factories. Common methodologies to remove copper are expensive and produce undesired by-products. A good decontaminating candidate should be environment-friendly, inexpensive, and capable of eliminating low concentrations of the metal. This work suggests chemically modified spent tea leaves of chamomile, peppermint and green tea in their thiolated, sulfonated and carboxylated forms as candidates for the removal of copper from solutions. Batch experiments were conducted to maximize the adsorption of copper (II) ions. Effects such as acidity, salinity, adsorbent dose, metal concentration, and presence of surfactant were explored. Experimental data show that maximum adsorption is reached at neutral pH. The results indicate that Cu(II) can be removed up to 53%, 22% and 19% with the thiolated, carboxylated and sulfonated adsorbents, respectively. Maximum adsorption of copper on TPM (53%) is achieved with 150 mg and decreases with the presence of salts and surfactants. Conversely, sulfonated and carboxylated adsorbents show better adsorption in the presence of surfactants. Time-dependent experiments show that adsorption is reached in less than 25 min for TCM and 5 min for SCM. Instrumental analyses determined the presence of active functional groups, thermal resistance, and scanning electron microscopy, indicating that both adsorbents are promising materials for the selective recovery and treatment of metal ions from wastewaters. Finally, columns were prepared with these adsorbents to explore their application in scaled-up processes, with very positive results. A long-term goal involves the recycling of the exhausted adsorbent and/or their use in the preparation of biofuels due to changes in materials’ structures.

Keywords: heavy metal removal, adsorption, wastewaters, water remediation

Procedia PDF Downloads 263
190 Fabrication of Cheap Novel 3d Porous Scaffolds Activated by Nano-Particles and Active Molecules for Bone Regeneration and Drug Delivery Applications

Authors: Mostafa Mabrouk, Basma E. Abdel-Ghany, Mona Moaness, Bothaina M. Abdel-Hady, Hanan H. Beherei

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Tissue engineering became a promising field for bone repair and regenerative medicine in which cultured cells, scaffolds and osteogenic inductive signals are used to regenerate tissues. The annual cost of treating bone defects in Egypt has been estimated to be many billions, while enormous costs are spent on imported bone grafts for bone injuries, tumors, and other pathologies associated with defective fracture healing. The current study is aimed at developing a more strategic approach in order to speed-up recovery after bone damage. This will reduce the risk of fatal surgical complications and improve the quality of life of people affected with such fractures. 3D scaffolds loaded with cheap nano-particles that possess an osteogenic effect were prepared by nano-electrospinning. The Microstructure and morphology characterizations of the 3D scaffolds were monitored using scanning electron microscopy (SEM). The physicochemical characterization was investigated using X-ray diffractometry (XRD) and infrared spectroscopy (IR). The Physicomechanical properties of the 3D scaffold were determined by a universal testing machine. The in vitro bioactivity of the 3D scaffold was assessed in simulated body fluid (SBF). The bone-bonding ability of novel 3D scaffolds was also evaluated. The obtained nanofibrous scaffolds demonstrated promising microstructure, physicochemical and physicomechanical features appropriate for enhanced bone regeneration. Therefore, the utilized nanomaterials loaded with the drug are greatly recommended as cheap alternatives to growth factors.

Keywords: bone regeneration, cheap scaffolds, nanomaterials, active molecules

Procedia PDF Downloads 158
189 Transesterification of Waste Cooking Oil for Biodiesel Production Using Modified Clinoptilolite Zeolite as a Heterogeneous Catalyst

Authors: D. Mowla, N. Rasti, P. Keshavarz

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Reduction of fossil fuels sources, increasing of pollution gases emission, and global warming effects increase the demand of renewable fuels. One of the main candidates of alternative fuels is biodiesel. Biodiesel limits greenhouse gas effects due to the closed CO2 cycle. Biodiesel has more biodegradability, lower combustion emissions such as CO, SOx, HC, PM and lower toxicity than petro diesel. However, biodiesel has high production cost due to high price of plant oils as raw material. So, the utilization of waste cooking oils (WCOs) as feedstock, due to their low price and disposal problems reduce biodiesel production cost. In this study, production of biodiesel by transesterification of methanol and WCO using modified sodic potassic (SP) clinoptilolite zeolite and sodic potassic calcic (SPC) clinoptilolite zeolite as heterogeneous catalysts have been investigated. These natural clinoptilolite zeolites were modified by KOH solution to increase the site activity. The optimum biodiesel yields for SP clinoptilolite and SPC clinoptilolite were 95.8% and 94.8%, respectively. Produced biodiesel were analyzed and compared with petro diesel and ASTM limits. The properties of produced biodiesel confirm well with ASTM limits. The density, kinematic viscosity, cetane index, flash point, cloud point, and pour point of produced biodiesel were all higher than petro diesel but its acid value was lower than petro diesel. Finally, the reusability and regeneration of catalysts were investigated. The results indicated that the spent zeolites cannot be reused directly for the transesterification, but they can be regenerated easily and can obtain high activity.

Keywords: biodiesel, renewable fuel, transesterification, waste cooking oil

Procedia PDF Downloads 211
188 Effect of Minimalist Footwear on Running Economy Following Exercise-Induced Fatigue

Authors: Jason Blair, Adeboye Adebayo, Mohamed Saad, Jeannette M. Byrne, Fabien A. Basset

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Running economy is a key physiological parameter of an individual’s running efficacy and a valid tool for predicting performance outcomes. Of the many factors known to influence running economy (RE), footwear certainly plays a role owing to its characteristics that vary substantially from model to model. Although minimalist footwear is believed to enhance RE and thereby endurance performance, conclusive research reports are scarce. Indeed, debates remain as to which footwear characteristics most alter RE. The purposes of this study were, therefore, two-fold: (a) to determine whether wearing minimalist shoes results in better RE compared to shod and to identify relationships with kinematic and muscle activation patterns; (b) to determine whether changes in RE with minimalist shoes are still evident following a fatiguing bout of exercise. Well-trained male distance runners (n=10; 29.0 ± 7.5 yrs; 71.0 ± 4.8 kg; 176.3 ± 6.5 cm) partook first in a maximal O₂ uptake determination test (VO₂ₘₐₓ = 61.6 ± 7.3 ml min⁻¹ kg⁻¹) 7 days prior to the experimental sessions. Second, in a fully randomized fashion, an RE test consisting of three 8-min treadmill runs in shod and minimalist footwear were performed prior to and following exercise induced fatigue (EIF). The minimalist and shod conditions were tested with a minimum of 7-day wash-out period between conditions. The RE bouts, interspaced by 2-min rest periods, were run at 2.79, 3.33, and 3.89 m s⁻¹ with a 1% grade. EIF consisted of 7 times 1000 m at 94-97% VO₂ₘₐₓ interspaced with 3-min recovery. Cardiorespiratory, electromyography (EMG), kinematics, rate of perceived exertion (RPE) and blood lactate were measured throughout the experimental sessions. A significant main speed effect on RE (p=0.001) and stride frequency (SF) (p=0.001) was observed. The pairwise comparisons showed that running at 2.79 m s⁻¹ was less economic compared to 3.33, and 3.89 m s⁻¹ (3.56 ± 0.38, 3.41 ± 0.45, 3.40 ± 0.45 ml O₂ kg⁻¹ km⁻¹; respectively) and that SF increased as a function of speed (79 ± 5, 82 ± 5, 84 ± 5 strides min⁻¹). Further, EMG analyses revealed that root mean square EMG significantly increased as a function of speed for all muscles (Biceps femoris, Gluteus maximus, Gastrocnemius, Tibialis anterior, Vastus lateralis). During EIF, the statistical analysis revealed a significant main effect of time on lactate production (from 2.7 ± 5.7 to 11.2 ± 6.2 mmol L⁻¹), RPE scores (from 7.6 ± 4.0 to 18.4 ± 2.7) and peak HR (from 171 ± 30 to 181 ± 20 bpm), expect for the recovery period. Surprisingly, a significant main footwear effect was observed on running speed during intervals (p=0.041). Participants ran faster with minimalist shoes compared to shod (3:24 ± 0:44 min [95%CI: 3:14-3:34] vs. 3:30 ± 0:47 min [95%CI: 3:19-3:41]). Although EIF altered lactate production and RPE scores, no other effect was noticeable on RE, EMG, and SF pre- and post-EIF, except for the expected speed effect. The significant footwear effect on running speed during EIF was unforeseen but could be due to shoe mass and/or heel-toe-drop differences. We also cannot discard the effect of speed on foot-strike pattern and therefore, running performance.

Keywords: exercise-induced fatigue, interval training, minimalist footwear, running economy

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187 Income Inequality among Selected Entrepreneurs in Ondo State, Nigeria

Authors: O.O. Ehinmowo, A.I. Fatuase, D.F. Oke

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Nigeria is endowed with resources that could boost the economy as well as generate income and provide jobs to the teaming populace. One of the keys of attaining this is by making the environment conducive for the entrepreneurs to excel in their respective enterprises so that more income could be accrued to the entrepreneurs. This study therefore examines income inequality among selected entrepreneurs in Ondo State, Nigeria using primary data. A multistage sampling technique was used to select 200 respondents for the study with the aid of structured questionnaire and personal interview. The data collected were subjected to descriptive statistics, Lorenz curve, Gini coefficient and Double - Log regression model. Results revealed that majority of the entrepreneurs (63%) were males and 90% were married with an average age of 44 years. About 40% of the respondents spent at most 12 years in school with 81% of the respondents had 4-6 members per household, while hair dressing (43.5%) and fashion designing (31.5%) were the most common enterprises among the sampled respondents. The findings also showed that majority of the entrepreneurs in hairdressing, fashion designing and laundry service earned below N200,000 per annum while the majority of those in restaurant and food vending earned between N400,000 – N600,000 followed by the entrepreneurs in pure water enterprise where majority earned N800,000 and above per annum. The result of the Gini coefficient (0.58) indicated that there was presence of inequality among the entrepreneurs which was also affirmed by the Lorenz curve. The Regression results showed that gender, household size and number of employees significantly affected the income of the entrepreneurs in the study area. Therefore, more female households should be encouraged into entrepreneurial businesses and government should give incentive cum conductive environment that could bridge the disparity in the income of the entrepreneurs in their various enterprises.

Keywords: entrepreneurs, Gini coefficient, income inequality, Lorenz curve

Procedia PDF Downloads 322
186 Impact of Human Resources Accounting on Employees' Performance in Organization

Authors: Hamid Saremi, Shida Hanafi

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In an age of technology and economics, human capital has important and axial role in the organization and human resource accounting has a wide perception to key resources of organization i.e. human resources. Human resources accounting is new branch of accounting that has Short-lived and generally deals to a range of policies and measures that are related to various aspects of human resources and It gives importance to an organization's most important asset is its human resources and human resource management is the key to success in an organization and to achieve this important matter must review and evaluation of human resources data be with knowledge of accounting based on empirical studies and methods of measurement and reporting of human resources accounting information. Undoubtedly human resource management without information cannot be done and take decision and human resources accounting is practical way to inform the decision makers who are committed to harnessing human resources,, human resources accounting with applying accounting principles in the organization and is with conducting basic research on the extent of the of human resources accounting information" effect of employees' personal performance. In human resource accounting analysis and criteria and valuation of cost and manpower valuating is as the main resource in each Institute. Protection of human resources is a process that according to human resources accounting is for organization profitability. In fact, this type of accounting can be called as a major source in measurement and trends of costs and human resources valuation in each institution. What is the economic value of such assets? What is the amount of expenditures for education and training of professional individuals to value in asset account? What amount of funds spent should be considered as lost opportunity cost? In this paper, according to the literature of human resource accounting we have studied the human resources matter and its objectives and topic of the importance of human resource valuation on employee performance review and method of reporting of human resources according to different models.

Keywords: human resources, human resources, accounting, human capital, human resource management, valuation and cost of human resources, employees, performance, organization

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185 The Role of Parents on Fear Acquisition of Children in COVID-19 Pandemic

Authors: Begum Serim-Yildiz

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The aim of this study is to examine the role of parents' emotional and behavioral reactions on fears of children in the COVID-19 pandemic considering Rachman’s Three Pathways Theory. For this purpose, a phenomenological qualitative study was conducted. Thirteen participants living with their children were utilized through criterion and snowball sampling. In semi-structured interviews parents were asked about their own and their children’s beahavioral and emotional reactions in the COVID-19 pandemic, and they were expected to give detailed information about fears of their children before and in pandemic. Firstly, parents were asked about their behavioral and emotional reactions in the COVID-19 pandemic. As behavioral reactions, precautions taken by parents to protect the rest of the family from negative physical and emotional impact of the pandemic were mentioned, while emotional reactions were defined as acquisition of negative emotions like fear, anxiety, and worry. Secondly, parents were asked about their children’s behavioral and emotional reactions. Some of the parents talked about positive behavioral changes such as gaining self-control, while some others explained negative behavioral changes like increased time spent with technological tools. In the emotional changes section, all of the parents explained at least one negative emotion. All of the parents stated that their children had COVID-19 related fears. According to parents’ expressions, fears of children in pandemic were examined in two dimensions. Fears directly related to COVID-19 were fear of virus/microbes, illness or death of someone in family and death and fears. Fears indirectly related to COVID-19 were fear of going out, sleep alone at night, separation, touching stuff outside the home, and cold. Considering existing literature and based on the findings of this study, it can be concluded that children’s modelling experiences have impact on acquisition of negative emotions, especially fear, therefore, preventive interventions involving caregivers should be provided by mental health professionals working with children.

Keywords: children’s fears, COVID-19 pandemic, modelling experiences, parents’ reactions

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184 Interactions between Residential Mobility, Car Ownership and Commute Mode: The Case for Melbourne

Authors: Solmaz Jahed Shiran, John Hearne, Tayebeh Saghapour

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Daily travel behavior is strongly influenced by the location of the places of residence, education, and employment. Hence a change in those locations due to a move or changes in an occupation leads to a change in travel behavior. Given the interventions of housing mobility and travel behaviors, the hypothesis is that a mobile housing market allows households to move as a result of any change in their life course, allowing them to be closer to central services, public transport facilities and workplace and hence reducing the time spent by individuals on daily travel. Conversely, household’s immobility may lead to longer commutes of residents, for example, after a change of a job or a need for new services such as schools for children who have reached their school age. This paper aims to investigate the association between residential mobility and travel behavior. The Victorian Integrated Survey of Travel and Activity (VISTA) data is used for the empirical analysis. Car ownership and journey to work time and distance of employed people are used as indicators of travel behavior. Change of usual residence within the last five years used to identify movers and non-movers. Statistical analysis, including regression models, is used to compare the travel behavior of movers and non-movers. The results show travel time, and the distance does not differ for movers and non-movers. However, this is not the case when taking into account the residence tenure-type. In addition, car ownership rate and number found to be significantly higher for non-movers. It is hoped that the results from this study will contribute to a better understanding of factors other than common socioeconomic and built environment features influencing travel behavior.

Keywords: journey to work, regression models, residential mobility, commute mode, car ownership

Procedia PDF Downloads 102
183 Investigating Malaysian Prereader’s Cognitive Processes when Reading English Picture Storybooks: A Comparative Eye-Tracking Experiment

Authors: Siew Ming Thang, Wong Hoo Keat, Chee Hao Sue, Fung Lan Loo, Ahju Rosalind

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There are numerous studies that explored young learners’ literacy skills in Malaysia but none that uses the eye-tracking device to track their cognitive processes when reading picture storybooks. This study used this method to investigate two groups of prereaders’ cognitive processes in four conditions. (1) A congruent picture was presented, and a matching narration was read aloud by a recorder; (2) Children heard a narration telling about the same characters in the picture but involves a different scene; (3) Only a picture with matching text was present; (4) Students only heard the reading aloud of the text on the screen. The two main objectives of this project are to test which content of pictures helps the prereaders (i.e., young children who have not received any formal reading instruction) understand the narration and whether children try to create a coherent mental representation from the oral narration and the pictures. The study compares two groups of children from two different kindergartens. Group1: 15 Chinese children; Group2: 17 Malay children. The medium of instruction was English. An eye-tracker were used to identify Areas of Interest (AOI) of each picture and the five target elements and calculate number of fixations and total time spent on fixation of pictures and written texts. Two mixed factorial ANOVAs with the storytelling performance (good, average, or weak) and vocabulary level (low, medium, high) as between-subject variables, and the Areas of Interests (AOIs) and display conditions as the within-subject variables were performedon the variables.

Keywords: eye-tracking, cognitive processes, literacy skills, prereaders, visual attention

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182 The Effect of Loud Working Environment on Incidence of Back Pain

Authors: Marcel Duh, Jadranka Stricevic, David Halozan, Dusan Celan

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Back pain is not only the result of structural or biomechanical abnormalities of the spine but is also associated with cognitive and behavioral aspects of pain and thus represents biopsychosocial problem. Stressors are not only interpersonal conflicts, negative life events, and dangerous situations but also noise. Effects of noise on human beings are psychological (excitement, stress), sensory, and physiological. The harmful effects of noise can be seen in the 40-65 dB range and are manifested as fatigue, irritability, poor sleep and psychological discomfort of the worker. Within 65-90 dB range, body metabolism increases, oxygen consumption is higher, tachycardia and hypertension appear, and the tone of skeletal muscles increases. The purpose of the study was to determine whether the stress caused by noise at the work place increases the incidence of back pain. Measurements of noise levels were carried out in three different wards of social care institution. The measurement on each ward was repeated 3 times (total of 9 measurements) for 8 hours during the morning shift. The device was set up in the room where clients spent most of the day. The staff on the ward replied to the questionnaire consisting of closed type questions about basic demographic information and information about back pain. We find that noise levels as measured in our study had no statistically significant effect on the incidence of back pain (p = 0.90). We also find that health care workers who perceive their work as stressful, have more back pain than those who perceive their job as unstressful, but correlation is statistically insignificant (p = 0.682). With our study, we have proven findings of other authors, that noise level below 65 dB does not have a significant influence on the incidence of back pain.

Keywords: health care workers, musculoskeletal disorder, noise, sick leave

Procedia PDF Downloads 101
181 Food Security in the Middle East and North Africa

Authors: Sara D. Garduno-Diaz, Philippe Y. Garduno-Diaz

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To date, one of the few comprehensive indicators for the measurement of food security is the Global Food Security Index. This index is a dynamic quantitative and qualitative bench marking model, constructed from 28 unique indicators, that measures drivers of food security across both developing and developed countries. Whereas the Global Food Security Index has been calculated across a set of 109 countries, in this paper we aim to present and compare, for the Middle East and North Africa (MENA), 1) the Food Security Index scores achieved and 2) the data available on affordability, availability, and quality of food. The data for this work was taken from the latest (2014) report published by the creators of the GFSI, which in turn used information from national and international statistical sources. According to the 2014 Global Food Security Index, MENA countries rank from place 17/109 (Israel, although with resent political turmoil this is likely to have changed) to place 91/109 (Yemen) with household expenditure spent in food ranging from 15.5% (Israel) to 60% (Egypt). Lower spending on food as a share of household consumption in most countries and better food safety net programs in the MENA have contributed to a notable increase in food affordability. The region has also however experienced a decline in food availability, owing to more limited food supplies and higher volatility of agricultural production. In terms of food quality and safety the MENA has the top ranking country (Israel). The most frequent challenges faced by the countries of the MENA include public expenditure on agricultural research and development as well as volatility of agricultural production. Food security is a complex phenomenon that interacts with many other indicators of a country’s well-being; in the MENA it is slowly but markedly improving.

Keywords: diet, food insecurity, global food security index, nutrition, sustainability

Procedia PDF Downloads 327
180 Assessing Sydney Tar Ponds Remediation and Natural Sediment Recovery in Nova Scotia, Canada

Authors: Tony R. Walker, N. Devin MacAskill, Andrew Thalhiemer

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Sydney Harbour, Nova Scotia has long been subject to effluent and atmospheric inputs of metals, polycyclic aromatic hydrocarbons (PAHs), and polychlorinated biphenyls (PCBs) from a large coking operation and steel plant that operated in Sydney for nearly a century until closure in 1988. Contaminated effluents from the industrial site resulted in the creation of the Sydney Tar Ponds, one of Canada’s largest contaminated sites. Since its closure, there have been several attempts to remediate this former industrial site and finally, in 2004, the governments of Canada and Nova Scotia committed to remediate the site to reduce potential ecological and human health risks to the environment. The Sydney Tar Ponds and Coke Ovens cleanup project has become the most prominent remediation project in Canada today. As an integral part of remediation of the site (i.e., which consisted of solidification/stabilization and associated capping of the Tar Ponds), an extensive multiple media environmental effects program was implemented to assess what effects remediation had on the surrounding environment, and, in particular, harbour sediments. Additionally, longer-term natural sediment recovery rates of select contaminants predicted for the harbour sediments were compared to current conditions. During remediation, potential contributions to sediment quality, in addition to remedial efforts, were evaluated which included a significant harbour dredging project, propeller wash from harbour traffic, storm events, adjacent loading/unloading of coal and municipal wastewater treatment discharges. Two sediment sampling methodologies, sediment grab and gravity corer, were also compared to evaluate the detection of subtle changes in sediment quality. Results indicated that overall spatial distribution pattern of historical contaminants remains unchanged, although at much lower concentrations than previously reported, due to natural recovery. Measurements of sediment indicator parameter concentrations confirmed that natural recovery rates of Sydney Harbour sediments were in broad agreement with predicted concentrations, in spite of ongoing remediation activities. Overall, most measured parameters in sediments showed little temporal variability even when using different sampling methodologies, during three years of remediation compared to baseline, except for the detection of significant increases in total PAH concentrations noted during one year of remediation monitoring. The data confirmed the effectiveness of mitigation measures implemented during construction relative to harbour sediment quality, despite other anthropogenic activities and the dynamic nature of the harbour.

Keywords: contaminated sediment, monitoring, recovery, remediation

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179 Study of Ageing in the Marine Environment of Bonded Composite Structures by Ultrasonic Guided Waves. Comparison of the Case of a Conventional Carbon-epoxy Composite and a Recyclable Resin-Based Composite

Authors: Hamza Hafidi Alaoui, Damien Leduc, Mounsif Ech Cherif El Kettani

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This study is dedicated to the evaluation of the ageing of turbine blades in sea conditions, based on ultrasonic Non Destructive Testing (NDT) methods. This study is being developed within the framework of the European Interreg TIGER project. The Tidal Stream Industry Energiser Project, known as TIGER, is the biggest ever Interreg project driving collaboration and cost reductionthrough tidal turbine installations in the UK and France. The TIGER project will drive the growth of tidal stream energy to become a greater part of the energy mix, with significant benefits for coastal communities. In the bay of Paimpol-Bréhat (Brittany), different samples of composite material and bonded composite/composite structures have been immersed at the same time near a turbine. The studied samples are either conventional carbon-epoxy composite samples or composite samples based on a recyclable resin (called recyclamine). One of the objectives of the study is to compare the ageing of the two types of structure. A sample of each structure is picked up every 3 to 6 months and analyzed using ultrasonic guided waves and bulk waves and compared to reference samples. In order to classify the damage level as a function of time spent under the sea, the measure have been compared to a rheological model based on the Finite Elements Method (FEM). Ageing of the composite material, as well as that of the adhesive, is identified. The aim is to improve the quality of the turbine blade structure in terms of longevity and reduced maintenance needs.

Keywords: non-destructive testing, ultrasound, composites, guides waves

Procedia PDF Downloads 188
178 Impact of Aging on Fatigue Performance of Novel Hybrid HMA

Authors: Faizan Asghar, Mohammad Jamal Khattak

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Aging, in general, refers to changes in rheological characteristics of asphalt mixture due to changes in chemical composition over the course of construction and service life of the pavement. The main goal of this study was to investigate the impact of oxidation on fatigue characteristics of a novel HMA composite fabricated with a combination of crumb rubber (CRM) and polyvinyl alcohol (PVA) fiber subject to aging of 7 and 14 days. A flexural beam fatigue test was performed to evaluate several characteristics of control, CRM modified, PVA reinforced, and novel rubber-fiber HMA composite. Experimental results revealed that aging had a significant impact on the fatigue performance of novel HMA composite. It was found that a suitable proportion of CRM and PVA radically affected the performance of novel rubber-fiber HMA in resistance to fracture and fatigue cracking when subjected to long-term aging. The developed novel HMA composite containing 2% CRM and 0.2% PVA presented around 29 times higher resistance to fatigue cracking for a period of 7 days of aging. To develop a cumulative plastic deformation level of 250 micros, such a mixture required over 50 times higher cycles than control HMA. Moreover, the crack propagation rate was reduced by over 90%, with over 12 times higher energy required to propagate a unit crack length in such a mixture compared to conventional HMA. Further, digital imaging correlation analyses revealed a more twisted and convoluted fracture path and higher strain distribution in rubber-fiber HMA composite. The fatigue performance after long-term aging of such novel HMA composite explicitly validates the ability to withstand load repetition that could lead to an extension in the service life of pavement infrastructure and reduce taxpayers’ dollars spent.

Keywords: crumb rubber, PVA fibers, dry process, aging, performance testing, fatigue life

Procedia PDF Downloads 45
177 Efficacy of Learning: Digital Sources versus Print

Authors: Rahimah Akbar, Abdullah Al-Hashemi, Hanan Taqi, Taiba Sadeq

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As technology continues to develop, teaching curriculums in both schools and universities have begun adopting a more computer/digital based approach to the transmission of knowledge and information, as opposed to the more old-fashioned use of textbooks. This gives rise to the question: Are there any differences in learning from a digital source over learning from a printed source, as in from a textbook? More specifically, which medium of information results in better long-term retention? A review of the confounding factors implicated in understanding the relationship between learning from the two different mediums was done. Alongside this, a 4-week cohort study involving 76 1st year English Language female students was performed, whereby the participants were divided into 2 groups. Group A studied material from a paper source (referred to as the Print Medium), and Group B studied material from a digital source (Digital Medium). The dependent variables were grading of memory recall indexed by a 4 point grading system, and total frequency of item repetition. The study was facilitated by advanced computer software called Super Memo. Results showed that, contrary to prevailing evidence, the Digital Medium group showed no statistically significant differences in terms of the shift from Remember (Episodic) to Know (Semantic) when all confounding factors were accounted for. The shift from Random Guess and Familiar to Remember occurred faster in the Digital Medium than it did in the Print Medium.

Keywords: digital medium, print medium, long-term memory recall, episodic memory, semantic memory, super memo, forgetting index, frequency of repetitions, total time spent

Procedia PDF Downloads 255