Search results for: opportunity cost
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7192

Search results for: opportunity cost

1312 Changing the Dynamics of the Regional Water Security in the Mekong River Basin: An Explorative Study Understanding the Cooperation and Conflict from Critical Hydropolitical Perspective

Authors: Richard Grünwald, Wenling Wang, Yan Feng

Abstract:

The presented paper explores the changing dynamics of regional water security in the Mekong River Basin and examines the contemporary water-related challenges from a critical hydropolitical perspective. By drawing on the Lancang-Mekong Cooperation and Conflict Database (LMCCD) recording more than 3000 water-related events within the basin in the last 30 years, we identified several trends changing the dynamics of the regional water security in the Mekong River Basin. Firstly, there is growing politicization of water that is no longer interpreted as abundant. While some scientists blame the rapid basin development, particularly in upstream countries, other researchers consider climate change and cumulative environmental impacts of various water projects as the main culprit for changing the water flow. Secondly, there is an increasing securitization of large-scale hydropower dams with questionable outcomes. Despite hydropower dams raise many controversies, many riparian states push the development at all cost. Such water security dilemma can be especially traced to Laos and Cambodia, which highly invest in the hydropower sector even at the expense of the local environment and good relations with neighbouring countries situated lower on the river. Thirdly, there is a lack of accountable transboundary water governance that will effectively face a looming water crisis. To date, most of the existing cooperation mechanisms are undermined by the geopolitical interests of foreign donors and increasing mistrust to scientific approaches dealing with water insecurity. Our findings are beneficial for the policy-makers and other water experts who want to grasp the broader hydropolitical context in the Mekong River Basin and better understand the new water security threats, including misinterpretation of the hydrological data and legitimization of the pro-development narratives.

Keywords: critical hydropolitics, mekong river, politicization of science, water governance, water security

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1311 Drivers and Barriers of Asphalt Rubber in Sweden

Authors: Raheb Mirzanamadi, João Patrício

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Asphalt rubber (AR) was initially developed in Sweden in the 1960s by replacing crumb rubber (CR) as aggregates in asphalt pavement. The AR produced by this method had better mechanical properties than conventional asphalt pavement but was very expensive. Since then, different technologies and methods have been developed to use CR in asphalt pavements, including blending CR with bitumen at a high temperature in the mixture, called the wet method, and blending CR with bitumen in the refinery, called the terminal blending method. In 2006, the wet method was imported from the USA to Sweden to evaluate the potential of using AR on Swedish roads. 154 km AR roads were constructed by the wet method in Sweden. The evaluation showed that the AR had, in most cases, better mechanical performance than conventional asphalt pavements. However, the terrible smoke and smell led the Swedish Transport Administration (STA) to stop using AR in Sweden. Today, there are few focuses on AR, despite its good mechanical properties and environmental aspects. Hence, there is a need to study the drives and barriers of using AR mixture in Sweden. The aims of this paper are: (i) to study drivers and barriers of using AR pavements in Sweden and (ii) to discover knowledge gaps for further research in this area. The study was done using a literature review and completed by interviews with experts, including three researchers from Swedish National Road and Transport Research Institute (VTI) and two experts from STA. The results showed that AR can be an alternative not only for conventional asphalt pavement but also for polymer modified asphalt (PMA) due to the same mechanical properties but the lower cost for production. New technologies such as terminal blending and using warm mix asphalt (WMA) methods can lead to reducing the energy and temperature during production processes. From this study, it is found that there is not enough experience and knowledge about AR in Sweden, and more research is needed, including the lifespan of AR, mechanical properties of AR using new technologies, and the impact of AR on spreading and leaching substances into nature. More studies can lead to standardization of using AR in Sweden, a potential solution for the use of end-of-life tyres, with better mechanical properties and lower costs, in comparison with conventional asphalt pavements and PMA.

Keywords: asphalt rubber, crumb rubber, terminal blending method, wet method

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1310 Circular Tool and Dynamic Approach to Grow the Entrepreneurship of Macroeconomic Metabolism

Authors: Maria Areias, Diogo Simões, Ana Figueiredo, Anishur Rahman, Filipa Figueiredo, João Nunes

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It is expected that close to 7 billion people will live in urban areas by 2050. In order to improve the sustainability of the territories and its transition towards circular economy, it’s necessary to understand its metabolism and promote and guide the entrepreneurship answer. The study of a macroeconomic metabolism involves the quantification of the inputs, outputs and storage of energy, water, materials and wastes for an urban region. This quantification and analysis representing one opportunity for the promotion of green entrepreneurship. There are several methods to assess the environmental impacts of an urban territory, such as human and environmental risk assessment (HERA), life cycle assessment (LCA), ecological footprint assessment (EF), material flow analysis (MFA), physical input-output table (PIOT), ecological network analysis (ENA), multicriteria decision analysis (MCDA) among others. However, no consensus exists about which of those assessment methods are best to analyze the sustainability of these complex systems. Taking into account the weaknesses and needs identified, the CiiM - Circular Innovation Inter-Municipality project aims to define an uniform and globally accepted methodology through the integration of various methodologies and dynamic approaches to increase the efficiency of macroeconomic metabolisms and promoting entrepreneurship in a circular economy. The pilot territory considered in CiiM project has a total area of 969,428 ha, comprising a total of 897,256 inhabitants (about 41% of the population of the Center Region). The main economic activities in the pilot territory, which contribute to a gross domestic product of 14.4 billion euros, are: social support activities for the elderly; construction of buildings; road transport of goods, retailing in supermarkets and hypermarkets; mass production of other garments; inpatient health facilities; and the manufacture of other components and accessories for motor vehicles. The region's business network is mostly constituted of micro and small companies (similar to the Central Region of Portugal), with a total of 53,708 companies identified in the CIM Region of Coimbra (39 large companies), 28,146 in the CIM Viseu Dão Lafões (22 large companies) and 24,953 in CIM Beiras and Serra da Estrela (13 large companies). For the construction of the database was taking into account data available at the National Institute of Statistics (INE), General Directorate of Energy and Geology (DGEG), Eurostat, Pordata, Strategy and Planning Office (GEP), Portuguese Environment Agency (APA), Commission for Coordination and Regional Development (CCDR) and Inter-municipal Community (CIM), as well as dedicated databases. In addition to the collection of statistical data, it was necessary to identify and characterize the different stakeholder groups in the pilot territory that are relevant to the different metabolism components under analysis. The CIIM project also adds the potential of a Geographic Information System (GIS) so that it is be possible to obtain geospatial results of the territorial metabolisms (rural and urban) of the pilot region. This platform will be a powerful visualization tool of flows of products/services that occur within the region and will support the stakeholders, improving their circular performance and identifying new business ideas and symbiotic partnerships.

Keywords: circular economy tools, life cycle assessment macroeconomic metabolism, multicriteria decision analysis, decision support tools, circular entrepreneurship, industrial and regional symbiosis

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1309 Implications of Stakeholder Theory as a Critical Theory

Authors: Louis Hickman

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Stakeholder theory is a powerful conception of the firm based on the notion that a primary focus on shareholders is inadequate and, in fact, detrimental to the long-term health of the firm. As such it represents a departure from prevalent business school teachings with their focus on accounting and cost controls. Herein, it is argued that stakeholder theory can be better conceptualized as a critical theory, or one which represents a fundamental change in business behavior and can transform the behavior of businesses if accepted. By arguing that financial interests underdetermine the success of the firm, stakeholder theory further democratizes business by endorsing an increased awareness of the importance of non-shareholder stakeholders. Stakeholder theory requires new, non-financial, measures of success that provide a new consciousness for management and businesses when conceiving their actions and place in society. Thereby, stakeholder theory can show individuals through self-reflection that the capitalist impulses to generate wealth cannot act as primary drivers of business behavior, but rather, that we would choose to support interests outside ourselves if we made the decision in free discussion. This is due to the false consciousness embedded in our capitalism that the firm’s finances are the foremost concern of modern organizations at the expense of other goals. A focus on non-shareholder stakeholders in addition to shareholders generates greater benefits for society by improving the state of customers, employees, suppliers, the community, and shareholders alike. These positive effects generate further positive gains in well-being for stakeholders and translate into increased health for the future firm. Additionally, shareholders are the only stakeholder group that does not provide long-term firm value since there are not always communities with qualified employees, suppliers capable of providing the quality of product needed, or persons with purchasing power for all conceivable products. Therefore, the firm’s long-term health is benefited most greatly by improving the greatest possible parts of the society in which it inhabits, rather than solely the shareholder.

Keywords: capitalism, critical theory, self-reflection, stakeholder theory

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1308 Media-Based Interventions to Influence English Language Learning: A Case of Bangladesh

Authors: Md. Mizanoor Rahman, Md. Zakir Hossain Talukder, M. Mahruf C. Shohel, Prithvi Shrestha

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In Bangladesh, classroom practice and English Learning (EL) competencies acquired both by the teacher and learner in primary and secondary schools are still very weak. Therefore, English is the most commonly failed examination subject at the school level; in addition, there are severe problems in communicative English by the Bangladeshi nationals– this has been characterized as a constraint to economic development. Job applicants and employees often lack English language skills necessary to work effectively. As a result; both government and its international development partners such as DFID, UNESCO, and CIDA have been very active to uplift the quality of the English language learning and implementing projects with innovative approaches. Recently; the economy has been increasing and in line with this, the technology has been deployed in English learning to improve reading, writing, speaking and listening skills. Young Bangladeshi creative, from a variety of backgrounds including film, animation, photography, and digital media are being trained to develop ideas for English Language Teaching (ELT) media. They are being motivated to develop a wide range of ideas for low cost English learning media products. English Language education policy in Bangladesh supports communicative language teaching practices and accordingly, actors have been influencing curriculum, textbook, deployment of technology and assessment changes supporting communicative ELT. The various projects are also being implemented to reform the curriculum, revise the textbook and adjust the assessment mechanism so that the country can increase in proficiency in communicative English among the population. At present; the numbers of teachers, students and adult learners classified at higher levels of proficiency because of deployment of technology and motivation for learning and using English among school population of Bangladesh. The current paper discusses the various interventions in Bangladesh with appropriate media to improve the competencies of the ELT among population.

Keywords: English learning, technology, education, psychological sciences

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1307 The Predictability of Three Implants to Support a Fixed Prosthesis in the Edentulous Mandible

Authors: M. Hirani, M. Devine, O. Obisesan, C. Bryant

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Introduction: The use of four or more implants to support a fixed prosthesis in the edentulous mandible is well documented, with high levels of clinical outcomes recorded. Despite this, the use of three implant-supported fixed prostheses offers the potential to deliver a more cost-effective method of oral rehabilitation in the lower arch, an important consideration given that edentulism is most prevalent in low-income subpopulations. The purpose of this study aimed to evaluate the implant and prosthetic survival rate, changes in marginal bone level, and patient satisfaction associated with a three-implant-supported fixed prosthesis for rehabilitation of the edentulous mandible over a follow-up period of at least one year. Methods: A comprehensive literature search was performed to evaluate studies that met the selection criteria. The information extracted included the study design and population, participant demographics, observation period, loading protocol, and the number of implants placed together with the required outcome measures. Mean values and standard deviations (SD) were calculated using SPSS® (IBM Corporation, New York, USA), and the level of statistical significance across all comparative studies described was set at P < 0.05. Results: The eligible studies included a total of 1968 implants that were placed in 652 patients. The subjects ranged in age from 33-89 years, with a mean of 63.2 years. The mean cumulative implant and prosthetic survival rates were 95.5% and 96.2%, respectively, over a mean follow-up period of 3.25 years. The mean marginal bone loss recorded was 1.04 mm, and high patient satisfaction rates were reported across the studies. Conclusion: Current evidence suggests that a three implant-supported fixed prosthesis for the edentulous mandible is a successful treatment strategy presenting high implant and prosthetic survival rates over the short-to-medium term. Further well-designed controlled clinical trials are required to evaluate longer-term outcomes, with supplemental data correlating implant dimensions and prosthetic design.

Keywords: implants, mandible, fixed, prosthesis

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1306 A Topology-Enabled Patient Connectivity Network to Bridge the Molecular-To-Phenotype Gap in Cholestasis

Authors: Doroteya K. Staykova, Dirk J. Lefeber, Sabine A. Fuchs, Judith J. M. Jans

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Cholestasis is characterized by the accumulation of toxic bile salts and lipids in the organism. The variety in causes (genetic, immunologic, environmental) and nature (benign, transient, chronic, progressive) combined with the need for early diagnosis and rapid clinical decisions emphasizes the need for good diagnostic strategies to improve patient outcomes. In a current diagnostic analysis of cholestasis, mass-spectrometry metabolomics is a widely adopted tool to enhance clinical decisions at point-of-care, thanks to a short turnaround in measurement times while performing comprehensive molecular profiling of patient material. However, this comes at the cost of difficult-to-identify yet actionable knowledge, often buried within large and heterogenous omics data. Here, we demonstrate how topological data analysis can overcome this challenge in large metabolomics datasets of patients with twenty categories of Metabolic Disorders and overlapping clinical manifestations. To elucidate the complexity of disease progression in three cholestasis patients, we applied topological data analysis to direct-infusion mass spectrometry data collected from 190 plasma samples, including 67 controls, at the University Medical Center in Utrecht, Netherlands. Using the Mapper algorithm and filter function defined as a two-component projection based on Principal Component Analysis, we constructed a topological graph of connected patients, termed a Patient Connectivity Network (PCN). With incorporated clinical and molecular information, PCN revealed the topological shape of causes and severity of cholestasis and transitions in patients’ conditions. In conclusion, topology based PCN provides a holistic view of cholestasis state dynamics that has the potential to support and expedite clinical decisions.

Keywords: mass spectrometry-based metabolomics, patient connectivity network, topological data analysis, unmet clinical needs in Cholestasis

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1305 Process Evaluation for a Trienzymatic System

Authors: C. Müller, T. Ortmann, S. Scholl, H. J. Jördening

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Multienzymatic catalysis can be used as an alternative to chemical synthesis or hydrolysis of polysaccharides for the production of high value oligosaccharides from cheap resources such as sucrose. However, development of multienzymatic processes is complex, especially with respect to suitable conditions for enzymes originating from different organisms. Furthermore, an optimal configuration of the catalysts in a reaction cascade has to be found. These challenges can be approached by design of experiments. The system investigated in this study is a trienzymatic catalyzed reaction which results in laminaribiose production from sucrose and comprises covalently immobilized sucrose phosphorylase (SP), glucose isomerase (GI) and laminaribiose phosphorylase (LP). Operational windows determined with design of experiments and kinetic data of the enzymes were used to optimize the enzyme ratio for maximum product formation and minimal production of byproducts. After adjustment of the enzyme activity ratio to 1: 1.74: 2.23 (SP: LP: GI), different process options were investigated in silico. The considered options included substrate dependency, the use of glucose as co-substrate and substitution of glucose isomerase by glucose addition. Modeling of batch operation in a stirred tank reactor led to yields of 44.4% whereas operation in a continuous stirred tank reactor resulted in product yields of 22.5%. The maximum yield in a bienzymatic system comprised of sucrose phosphorylase and laminaribiose phosphorylase was 67.7% with sucrose and different amounts of glucose as substrate. The experimental data was in good compliance with the process model for batch operation. The continuous operation will be investigated in further studies. Simulation of operational process possibilities enabled us to compare various operational modes regarding different aspects such as cost efficiency, with the minimum amount of expensive and time-consuming practical experiments. This gives us more flexibility in process implementation and allows us, for example, to change the production goal from laminaribiose to higher oligosaccharides.

Keywords: design of experiments, enzyme kinetics, multi-enzymatic system, in silico process development

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1304 Nanomaterials-Assisted Drilling Fluids for Application in Oil Fields - Challenges and Prospects

Authors: Husam Mohammed Saleh Alziyadi

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The drilling fluid has a significant impact on drilling efficiency. Drilling fluids have several functions which make them most important within the drilling process, such as lubricating and cooling the drill bit, removing cuttings from down of hole, preventing formation damage, suspending drill bit cuttings, , and also removing permeable formation as a result, the flow of fluid into the formation process is delayed. In the oil and gas sector, unconventional shale reserves have been a central player in meeting world energy demands. Oil-based drilling fluids (OBM) are generally favored for drilling shale plays due to negligible chemical interactions. Nevertheless, the industry has been inspired by strict environmental regulations to design water-based drilling fluids (WBM) capable of regulating shale-water interactions to boost their efficiency. However, traditional additives are too large to plug the micro-fractures and nanopores of the shale. Recently, nanotechnology in the oil and gas industries has shown a lot of promise, especially with drilling fluids based on nanoparticles. Nanotechnology has already made a huge contribution to technical developments in the energy sector. In the drilling industry, nanotechnology can make revolutionary changes. Nanotechnology creates nanomaterials with many attractive properties that can play an important role in improving the consistency of mud cake, reducing friction, preventing differential pipe sticking, preserving the stability of the borehole, protecting reservoirs, and improving the recovery of oil and gas. The selection of suitable nanomaterials should be based on the shale formation characteristics intended for drilling. The size, concentration, and stability of the NPs are three more important considerations. The effects of the environment are highly sensitive to these materials, such as changes in ionic strength, temperature, or pH, all of which occur under downhole conditions. This review paper focused on the previous research and recent development of environmentally friendly drilling fluids according to the regulatory environment and cost challenges.

Keywords: nanotechnology, WBM, Drilling Fluid, nanofluids

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1303 Towards Better Integration: Qualitative Study on Perceptions of Russian-Speaking Immigrants in Australia

Authors: Oleg Shovkovyy

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This research conducted in response to one of the most pressing questions on the agenda of many public administration offices around the world: “What could be done for better integration and assimilation of immigrants into hosting communities?” In author’s view, the answer could be suggested by immigrants themselves. They, often ‘bogged down in the past,’ snared by own idols and demons, perceive things differently, which, in turn, may result in their inability to integrate smoothly into hosting communities. Brief literature review suggests that perceptions of immigrants are completely neglected or something unsought in the current research on migrants, which, often, based on opinion polls by members of hosting communities themselves or superficial research data by various research organizations. Even those specimens that include voices of immigrants, unlikely to shed any additional light onto the problem simply because certain things are not made to speak out loud, especially to those in whose hands immigrants’ fate is (authorities). In this regard, this qualitative study, conducted by an insider to a few Russian-speaking communities, represents a unique opportunity for all stakeholders to look at the question of integration through the eyes of immigrants, from a different perspective and thus, makes research findings especially valuable for better understanding of the problem. Case study research employed ethnographic methods of gathering data where, approximately 200 Russian-speaking immigrants of first and second generations were closely observed by the Russian-speaking researcher in their usual setting, for eight months, and at different venues. The number of informal interviews with 27 key informants, with whom the researcher managed to establish a good rapport and who were keen enough to share their experiences voluntarily, were conducted. The field notes were taken at 14 locations (study sites) within the Brisbane region of Queensland, Australia. Moreover, all this time, researcher lived in dwelling of one of the immigrants and was an active participant in the social life (worship, picnics, dinners, weekend schools, concerts, cultural events, social gathering, etc.) of observed communities, whose members, to a large extent, belong to various religious lines of the Russian and Protestant Church. It was found that the majority of immigrants had experienced some discrimination in matters of hiring, employment, recognition of educational qualifications from home countries, and simply felt a sort of dislike from society in various everyday situations. Many noted complete absences or very limited state assistance in terms of employment, training, education, and housing. For instance, the Australian Government Department of Human Services not only does not stimulate job search but, on the contrary, encourages to refuse short-term works and employment. On the other hand, offered free courses on adaptation, and the English language proved to be ineffective and unpopular amongst immigrants. Many interviewees have reported overstated requirements for English proficiency and local work experience, whereas it was not critical for the given task or job. Based on the result of long-term monitoring, the researcher also had the courage to assert the negative and decelerating roles of immigrants’ communities, particularly religious communities, on processes of integration and assimilation. The findings suggest that governments should either change current immigration policies in the direction of their toughening or to take more proactive and responsible role in dealing with immigrant-related issues; for instance, increasing assistance and support to all immigrants and probably, paying more attention to and taking stake in managing and organizing lives of immigrants’ communities rather, simply leaving it all to chance.

Keywords: Australia, immigration, integration, perceptions

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1302 Upsouth: Digitally Empowering Rangatahi (Youth) and Whaanau (Families) to Build Skills in Critical and Creative Thinking to Achieve More Active Citizenship in Aotearoa New Zealand

Authors: Ayla Hoeta

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In a post-colonial Aotearoa New Zealand, solutions by rangatahi (youth) for rangatahi are essential as is civic participation and building economic agency in an increasingly tough economic climate. Upsouth was an online community crowdsourcing platform developed by The Southern Initiative, in collaboration with Itsnoon that provides rangatahi and whānau (family) a safe space to share lived experience, thoughts and ideas about local kaupapa (issues/topics) of importance to them. The target participants were Māori indigenous peoples and Pacifica groups, aged 14 - 21 years. In the Aotearoa New Zealand context, this participant group is not likely to engage in traditional consultation processes despite being an essential constituent in helping shape better local communities, whānau and futures. The Upsouth platform was active for two years from 2018-2019 where it completed 42 callups with 4300+ participants. The web platform collates the ideas, voices, feedback, and content of users around a callup that has been commissioned by a sponsor, such as Auckland Council, Z Energy or Auckland Transport. A callup may be about a pressing challenge in a community such as climate change, a new housing development, homelessness etc. Each callup was funded by the sponsor with Upsouths main point of difference being that participants are given koha (money donation) through digital wallets for their ideas. Depending on the quality of what participants upload, the koha varies between small micropayments and larger payments. This encouraged participants to develop creative and critical thinking - upskilling for future focussed jobs, enterprise and democratic skills while earning pocket money at the same time. Upsouth enables youth-led action and voice, and empowers them to be a part of a reciprocal and creative economy. Rangatahi are encouraged to express themselves culturally, creatively, freely and in a way they are free to choose - for example, spoken word, song, dance, video, drawings, and/or poems. This challenges and changes what is considered acceptable as community engagement feedback by the local government. Many traditional engagement platforms are not as consultative, do not accept diverse types of feedback, nor incentivise this valuable expression of feedback. Upsouth is also empowering for rangatahi, since it allows them the opportunity to express their opinions directly to the government. Upsouth gained national and international recognition for the way it engages with youth: winning the Supreme Award and the Accessibility and Transparency Award at Auckland Council’s 2018 Engagement Awards, becoming a finalist in the 2018 Digital Equity and Accessibility category of International Data Corporation’s Smart City Asia and Pacific Awards. This paper will fully contextualize the challenges of rangatahi and whānau civic engagement in Aotearoa New Zealand and then present a reflective case study of the Upsouth project, with examples from some of the callups. This is intended to form part of the Divided Cities 22 conference New Ground sub-theme as a critical reflection on a design intervention, which was conceived and implemented by the lead author to overcome the post-colonial divisions of Māori, Pacifica and minority ethnic rangatahi in Aotearoa New Zealand.

Keywords: rangatahi, youth empowerment, civic engagement, enabling, relating, digital platform, participation

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1301 Design and Tooth Contact Analysis of Face Gear Drive with Modified Tooth Surface in Helicopter Transmission

Authors: Kazumasa Kawasaki, Isamu Tsuji, Hiroshi Gunbara

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A face gear drive is actually composed of a spur or helical pinion that is in mesh with a face gear and transfers power and motion between intersecting or skew axes. Due to the peculiarity of the face gear drive in shunt and confluence drive, it shows potential advantages in the application in the helicopter transmission. The advantages of such applications are the possibility of the split of the torque that appears to be significant where a pinion drives two face gears to provide an accurate division of power and motion. This mechanism greatly reduces the weight and cost compared to conventional design. Therefore, this has been led to revived interest and the face gear drive has been utilized in substitution for bevel and hypoid gears in limited cases. The face gear drive with a spur or a helical pinion is newly designed in order to determine an effective meshing area under the design parameters and specific design dimensions. The face gear has two unique dimensions which control the face width of the tooth, and the outside and inside diameters of the face gear. On the other hand, it is necessary to modify the tooth surfaces of face gear drive in order to avoid the influences of alignment errors on the tooth contact patterns in practical use. In this case, the pinion tooth surfaces are usually modified in the conventional method. However, it is hard to control the tooth contact pattern intentionally and adjust the position of the pinion axis in meshing of the gear pair. Therefore, a method of the modification of the tooth surfaces of the face gear is proposed. Moreover, based on tooth contact analysis, the tooth contact pattern and transmission errors of the designed face gear drive are analyzed, and the influences of alignment errors on the tooth contact patterns and transmission errors are investigated. These results showed that the tooth contact patterns and transmission errors were controllable and the face gear drive which is insensitive to alignment errors can be obtained.

Keywords: alignment error, face gear, gear design, helicopter transmission, tooth contact analysis

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1300 Decreasing Non-Compliance with the Garbage Collection Fee Payment: A Case Study from the Intervention in a Municipality in the Slovak Republic

Authors: Anetta Caplanova, Eva Sirakovova, Estera Szakadatova

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Non-payment of taxes and fees represents a problem, which occurs at national and local government levels in many countries. An effective tax collection is key for generating government and local government budget revenues to finance public services and infrastructure; thus, there is the need to address this problem. The standard approach considers as a solution raising taxes/fees to boost public revenues, which may be politically challenging and time-consuming to implement. An alternative approach is related to using behavioral interventions. These can be usually implemented relatively quickly, and in most cases, they are associated with low cost. In the paper, we present the results of the behavioral experiment focused on raising the level of compliance with the payment of garbage collection fees in a selected municipality in the Slovak Republic. The experiment was implemented using the leaflets sent to residential households together with the invoice for the garbage collection in the municipality Hlohovec, Western Slovakia, in Spring 2021. The sample of about 10000 households was divided into three random groups, a control group and two intervention groups. Households in intervention group 1 were sent a leaflet using the social norm nudge, while households in intervention group 2 were sent a leaflet using the deterrence nudge. The social norm framing leaflet pointed out that in the municipality, the prevailing majority of people paid the garbage collection fee and encouraged recipients to join this majority. The deterrent leaflet reminded the recipients that if they did not pay the fee on time, enforcement proceedings would follow. This was aimed to increase the subjective perception of citizens of the enforcement proceedings in case of noncompliance. In the paper, we present and discuss the results from the experiment and formulate relevant generalizations for other municipalities.

Keywords: municipal governments, garbage fee collection, behavioural intervention, social norm, deterrence nudge

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1299 Analysis of the Effect of Farmers’ Socio-Economic Factors on Net Farm Income of Catfish Farmers in Kwara State, Nigeria

Authors: Olanike A. Ojo, Akindele M. Ojo, Jacob H. Tsado, Ramatu U. Kutigi

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The study was carried out on analysis of the effect of farmers’ socio-economic factors on the net farm income of catfish farmers in Kwara State, Nigeria. Primary data were collected from selected catfish farmers with the aid of well-structured questionnaire and a multistage sampling technique was used to select 102 catfish farmers in the area. The analytical techniques involved the use of descriptive statistics and multiple regression analysis. The findings of the analysis of socio-economic characteristics of catfish farmers reveal that 60% of the catfish farmers in the study area were male gender which implied the existence of gender inequality in the area. The mean age of 47 years was an indication that they were at their economically productive age and could contribute positively to increased production of catfish in the area. Also, the mean household size was five while the mean year of experience was five. The latter implied that the farmers were experienced in fishing techniques, breeding and fish culture which would assist in generating more revenue, reduce cost of production and eventual increase in profit levels of the farmers. The result also revealed that stock capacity (X3), accessibility to credit (X7) and labour (X4) were the main determinants of catfish production in the area. In addition, farmer’s sex, household size, no of ponds, distance of the farm from market, access to credit were the main socio-economic factors influencing the net farm income of the catfish farmers in the area. The most serious constraints militating against catfish production in the study area were high mortality rate, insufficient market, inadequate credit facilities/ finance and inadequate skilled labour needed for daily production routine. Based on the findings, it is therefore recommended that, to reduce the mortality rate of catfish extension agents should organize training workshops on improved methods and techniques of raising catfish right from juvenile to market size.

Keywords: credit, income, stock, mortality

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1298 Study of Electro-Chemical Properties of ZnO Nanowires for Various Application

Authors: Meera A. Albloushi, Adel B. Gougam

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The development in the field of piezoelectrics has led to a renewed interest in ZnO nanowires (NWs) as a promising material in the nanogenerator devices category. It can be used as a power source for self-powered electronic systems with higher density, higher efficiency, longer lifetime, as well as lower cost of fabrication. Highly aligned ZnO nanowires seem to exhibit a higher performance compared with nonaligned ones. The purpose of this study was to develop ZnO nanowires and to investigate their electrical and chemical properties for various applications. They were grown on silicon (100) and glass substrates. We have used a low temperature and non-hazardous method: aqueous chemical growth (ACG). ZnO (non-doped) and AZO (Aluminum doped) seed layers were deposited using RF magnetron sputteringunder Argon pressure of 3 mTorr and deposition power of 180 W, the times of growth were selected to obtain thicknesses in the range of 30 to 125 nm. Some of the films were subsequently annealed. The substrates were immersed tilted in an equimolar solution composed of zinc nitrate and hexamine (HMTA) of 0.02 M and 0.05 M in the temperature range of 80 to 90 ᵒC for 1.5 to 2 hours. The X-ray diffractometer shows strong peaks at 2Ө = 34.2ᵒ of ZnO films which indicates that the films have a preferred c-axis wurtzite hexagonal (002) orientation. The surface morphology of the films is investigated by atomic force microscope (AFM) which proved the uniformity of the film since the roughness is within 5 nm range. The scanning electron microscopes(SEM) (Quanta FEG 250, Quanta 3D FEG, Nova NanoSEM 650) are used to characterize both ZnO film and NWs. SEM images show forest of ZnO NWs grown vertically and have a range of length up to 2000 nm and diameter of 20-300 nm. The SEM images prove that the role of the seed layer is to enhance the vertical alignment of ZnO NWs at the pH solution of 5-6. Also electrical and optical properties of the NWs are carried out using Electrical Force Microscopy (EFM). After growing the ZnO NWs, developing the nano-generator is the second step of this study in order to determine the energy conversion efficiency and the power output.

Keywords: ZnO nanowires(NWs), aqueous chemical growth (ACG), piezoelectric NWs, harvesting enery

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1297 Design of an Active Compression System for Treating Vascular Disease Using a Series of Silicone Based Inflatable Mini Bladders

Authors: Gayani K. Nandasiri, Tilak Dias, William Hurley

Abstract:

Venous disease of human lower limb could range from minor asymptomatic incompetence of venous valves to chronic venous ulceration. The sheer prevalence of varicose veins and its associated significant costs of treating late complications such as chronic ulcers contribute to a higher burden on health care resources. In most of western countries with developed health care systems, treatment costs associated with Venous disease accounts for a considerable portion of their total health care budget, and it has become a high-cost burden to National Health Service (NHS), UK. The established gold standard of treatment for the venous disease is the graduated compression, where the pressure at the ankle being highest and decreasing towards the knee and thigh. Currently, medical practitioners use two main methods to treat venous disease; i.e. compression bandaging and compression stockings. Both these systems have their own disadvantages which lead to the current programme of research. The aim of the present study is to revolutionize the compression therapy by using a novel active compression system to deliver a controllable and more accurate pressure profiles using a series of inflatable mini bladders. Two types of commercially available silicones were tested for the application. The mini bladders were designed with a special fabrication procedure to provide required pressure profiles, and a series of experiments were conducted to characterise the mini bladders. The inflation/deflation heights of these mini bladders were investigated experimentally and using a finite element model (FEM), and the experimental data were compared to the results obtained from FEM simulations, which showed 70-80% agreement. Finally, the mini bladders were tested for its pressure transmittance characteristics, and the results showed a 70-80% of inlet air pressure transmitted onto the treated surface.

Keywords: finite element analysis, graduated compression, inflatable bladders, venous disease

Procedia PDF Downloads 161
1296 Study of Linear Generator for Vibration Energy Harvesting of Frequency more than 50Hz

Authors: Seong-Jin Cho, Jin Ho Kim

Abstract:

Energy harvesting is the technology which gathers and converts external energies such as light, vibration and heat which are disposed into reusable electrical energy and uses such electrical energy. The vibration energy harvesting is very interesting technology because it produces very high density of energy and unaffected by the climate. Vibration energy can be harvested by the electrostatic, electromagnetic and piezoelectric systems. The electrostatic system has low energy conversion efficiency, and the piezoelectric system is expensive and needs the frequent maintenance because it is made of piezoelectric ceramic. On the other hand, the electromagnetic system has a long life time and high harvesting efficiency, and it is relatively cheap. The electromagnetic harvesting system includes the linear generator and the rotary-type generator. The rotary-type generators require the additional mechanical conversion device if it uses linear motion of vibration. But, the linear generator uses directly linear motion of vibration without a mechanical conversion device, and it has uncomplicated structure and light weight compared with the rotary-type generator. Therefore, the linear electromagnetic generator can be useful in using vibration energy harvesting. The pole transformer systems need electricity sensor system for sending voltage and power information to administrator. Therefore, the battery is essential, and its regular maintenance of replacement is required. In case of the transformer of high location in mountainous areas, the person can’t easily access it resulting in high maintenance cost. To overcome these problems, we designed and developed the linear electromagnetic generator which can replace battery in electricity sensor system for sending voltage and power information of the pole transformer. And, it uses vibration energy of frequency more than 50 Hz by the pole transformer. In order to analyze the electromagnetic characteristics of small linear electric generator, a commercial electromagnetic finite element analysis program "MAXWELL" was used. Then, through the actual production and experiment of linear generator, we confirmed output power of linear generator.

Keywords: energy harvesting, frequency, linear generator, experiment

Procedia PDF Downloads 234
1295 Demonstration Operation of Distributed Power Generation System Based on Carbonized Biomass Gasification

Authors: Kunio Yoshikawa, Ding Lu

Abstract:

Small-scale, distributed and low-cost biomass power generation technologies are highly required in the modern society. There are big needs for these technologies in the disaster areas of developed countries and un-electrified rural areas of developing countries. This work aims to present a technical feasibility of the portable ultra-small power generation system based on the gasification of carbonized wood pellets/briquettes. Our project is designed for enabling independent energy production from various kinds of biomass resources in the open-field. The whole process mainly consists of two processes: biomass and waste pretreatment; gasification and power generation. The first process includes carbonization, densification (briquetting or pelletization), and the second includes updraft fixed bed gasification of carbonized pellets/briquettes, syngas purification, and power generation employing an internal combustion gas engine. A combined pretreatment processes including carbonization without external energy and densification were adopted to deal with various biomass. Carbonized pellets showed a better gasification performance than carbonized briquettes and their mixture. The 100-hour continuous operation results indicated that pelletization/briquetting of carbonized fuel realized the stable operation of an updraft gasifier if there were no blocking issues caused by the accumulation of tar. The cold gas efficiency and the carbon conversion during carbonized wood pellets gasification was about 49.2% and 70.5% with the air equivalence ratio value of around 0.32, and the corresponding overall efficiency of the gas engine was 20.3% during the stable stage. Moreover, the maximum output power was 21 kW at the air flow rate of 40 Nm³·h⁻¹. Therefore, the comprehensive system covering biomass carbonization, densification, gasification, syngas purification, and engine system is feasible for portable, ultra-small power generation. This work has been supported by Innovative Science and Technology Initiative for Security (Ministry of Defence, Japan).

Keywords: biomass carbonization, densification, distributed power generation, gasification

Procedia PDF Downloads 124
1294 Anticancer and Anti-Apoptotic Potential of Tridham and 1,2,3,4,6-Penta-O-Galloyl-β-D-Glucose in MCF-7 Breast Cancer Cell Line

Authors: R. Stalin, D. Karthick, H. Haseena Banu, T. P. Sachidanandam, P. Shanthi

Abstract:

Background: Breast cancer is emerging as one of the leading cause of cancer related deaths and hence there arises the need to look out for drugs which are more targets specific with minimal side effects. In recent times, there is a shift towards alternative medicine due to low cost and less side effects. Siddha system of medicine is one the oldest system of medicine practiced against various ailments. Tridham (TD) is a herbal formulation prepared in our laboratory consisting of Terminalia chebula, Elaeocarpus ganitrus and Prosopis cineraria in a definite ratio (TD) and its anticancer potential is evaluated in terms of induction of apoptosis. Objective: The present study was designed to investigate the anti proliferative effect of TD and 1,2,3,4,6-penta-O-galloyl-b-D-glucose (PGG), a pure compound isolated from TD on human mammary carcinoma cell line (MCF-7). Materials and Methods: Cell viability was studied using MTT analysis and trypan blue staining. Mitochondrial membrane potential was studied using DAPI staining. The protein and mRNA expressions of pro-apoptotic and anti- apoptotic markers namely Bax, Bad, Bcl-2 and caspases were also assessed by Western Blotting and RT PCR. Results: Viability studies of TD and PGG treated MCF-7 cells showed an inhibition in cell growth in time and dose dependent manner. The alteration in mitochondrial membrane potential was restored through treatment with TD and PGG which was confirmed by DAPI staining. The protein and mRNA expression of pro-apoptotic markers was found to be significantly increased in TD and PGG treated cells with a concomitant decrease in anti-apoptotic markers. Conclusion: The results of the study suggest that TD and PGG exhibit their anticancer effect through its membrane stabilizing property and activation of apoptotic cascade in MCF-7 cells.

Keywords: apoptosis, mammary carcinoma, MCF-7, penta galloyl glucose, Tridham

Procedia PDF Downloads 286
1293 In-vitro Metabolic Fingerprinting Using Plasmonic Chips by Laser Desorption/Ionization Mass Spectrometry

Authors: Vadanasundari Vedarethinam, Kun Qian

Abstract:

The metabolic analysis is more distal over proteomics and genomics engaging in clinics and needs rationally distinct techniques, designed materials, and device for clinical diagnosis. Conventional techniques such as spectroscopic techniques, biochemical analyzers, and electrochemical have been used for metabolic diagnosis. Currently, there are four major challenges including (I) long-term process in sample pretreatment; (II) difficulties in direct metabolic analysis of biosamples due to complexity (III) low molecular weight metabolite detection with accuracy and (IV) construction of diagnostic tools by materials and device-based platforms for real case application in biomedical applications. Development of chips with nanomaterial is promising to address these critical issues. Mass spectroscopy (MS) has displayed high sensitivity and accuracy, throughput, reproducibility, and resolution for molecular analysis. Particularly laser desorption/ ionization mass spectrometry (LDI MS) combined with devices affords desirable speed for mass measurement in seconds and high sensitivity with low cost towards large scale uses. We developed a plasmonic chip for clinical metabolic fingerprinting as a hot carrier in LDI MS by series of chips with gold nanoshells on the surface through controlled particle synthesis, dip-coating, and gold sputtering for mass production. We integrated the optimized chip with microarrays for laboratory automation and nanoscaled experiments, which afforded direct high-performance metabolic fingerprinting by LDI MS using 500 nL of serum, urine, cerebrospinal fluids (CSF) and exosomes. Further, we demonstrated on-chip direct in-vitro metabolic diagnosis of early-stage lung cancer patients using serum and exosomes without any pretreatment or purifications. To our best knowledge, this work initiates a bionanotechnology based platform for advanced metabolic analysis toward large-scale diagnostic use.

Keywords: plasmonic chip, metabolic fingerprinting, LDI MS, in-vitro diagnostics

Procedia PDF Downloads 137
1292 Seroprevalence of Toxoplasmosis among Hemato-Oncology Patients in Tertiary Hospital of East Cost Malaysia

Authors: Aisha Khodijah Kholib Jati, Suharni Mohamad, Azlan Husin, Wan Suriana Wan Ab Rahman

Abstract:

Introduction: Toxoplasmosis is caused by an obligate intracellular parasite, Toxoplasma gondii (T. gondii). It is commonly asymptomatic in normal individual, but it can be fatal to immunocompromised patients as it can lead to severe complications such as encephalitis, chorioetinitis and myocarditis. Objective: The aim of the study was to determine the seroprevalence of toxoplasmosis and its association with socio-demographic and behavioral characteristics among hemato-oncology patients in Hospital USM. Methods: In this cross-sectional study, 56 hemato-oncology patients were screened for immunoglobulin M (IgM) antibodies, immunoglobulin G (IgG) antibodies, and IgG avidity of T. gondii by using ELISA Kit (BioRad, USA). For anti-T. gondii IgG antibody, titer ≥ 9 IU/ml was considered as recent infection, while for IgM, ratio ≥ 1.00 was considered as reactive for the anti-T. gondii IgM antibodies. Low avidity index is considered as recent infection within 20 weeks while high avidity considered as past infection. T. gondii exposure, socio-demographic and behavioral characteristics was assessed by a questionnaire and interview. Results: A total of 28 (50.0%) hemato-oncology patients were seropositive for T. gondii antibodies. Out of that total, 27 (48.21%) patients were IgG+/IgM- and one patient (1.79%) was IgG+/IgM+ with high avidity index. Univariate analysis showed that age, gender, ethnicity, marital status, educational level, employment status, stem cell transplant, blood transfusion, close contact with cats, water supply, and consumption of undercooked meat were not significantly associated with Toxoplasma seropositivity rate. Discussion: The seropositivity rate of IgG anti-T. gondii was high among hemato-oncology patients in Hospital USM. With impaired immune system, these patients might have a severe consequence if the infection reactivated. Therefore, screening for anti-T. gondii may be considered in the future. Moreover, health programme towards healthy food and good hygiene practice need to be implemented.

Keywords: immunocompromised, seroprevalence, socio-demographic, toxoplasmosis

Procedia PDF Downloads 130
1291 Performance Study of Experimental Ferritic Alloy with High Content of Molybdenum in Corrosive Environment of Soybean Methyl Biodiesel

Authors: Maurício N. Kleinberg, Ana P. R. N. Barroso, Frederico R. Silva, Natasha l. Gomes, Rodrigo F. Guimarães, Marcelo M. V. Parente, Jackson Q. Malveira

Abstract:

Increased production of biofuels, especially biodiesel, as an option to replace the diesel derived from oil is already a reality in countries seeking a renewable and environmentally friendly fuel, as is the case in Brazil. However, it is known that the use of fuels, renewable or not, implies that it is in contact with various metallic materials which may cause corrosion. In the search for more corrosion resistant materials has been experimentally observed that the addition of molybdenum in ferritic steels increases their protective character without significantly burdening the cost of production. In order to evaluate the effect of adding molybdenum, samples of commercial steel (austenitic, ferritic and carbon steel) and the experimental ferritic alloy with a high molybdenum content (5.3%) were immersed separately into biodiesel derived from transesterification of soy oil to monitor the corrosion process of these metal samples, and in parallel to analyze the oxidative degradation of biodiesel itself. During the immersion time of 258 days, biodiesel samples were taken for analysis of acidity, kinematic viscosity, density and refraction. Likewise, the metal samples were taken from the biodiesel to be weighed and microstructurally analyzed by light microscopy. The results obtained at the end of 258 days shown that biodiesel presented a considerable increase on the values of the studied parameters for all the samples. However, this increase was not able to produce significant mass loss in metallic samples. As regards the microstructural analysis, it showed the onset of surface oxidation on the carbon steel sample. As for the other samples, no significant surface changes were shown. These results are consistent with literature for short immersion times. It is concluded that the increase in the values of the studied parameters is not significant yet, probably due to the low time of immersion and exposure of the samples. Thus, it is necessary to continue the tests so that the objectives of this work are achieved.

Keywords: biodiesel, corrosion, immersion, experimental alloy

Procedia PDF Downloads 417
1290 Coupled Space and Time Homogenization of Viscoelastic-Viscoplastic Composites

Authors: Sarra Haouala, Issam Doghri

Abstract:

In this work, a multiscale computational strategy is proposed for the analysis of structures, which are described at a refined level both in space and in time. The proposal is applied to two-phase viscoelastic-viscoplastic (VE-VP) reinforced thermoplastics subjected to large numbers of cycles. The main aim is to predict the effective long time response while reducing the computational cost considerably. The proposed computational framework is a combination of the mean-field space homogenization based on the generalized incrementally affine formulation for VE-VP composites, and the asymptotic time homogenization approach for coupled isotropic VE-VP homogeneous solids under large numbers of cycles. The time homogenization method is based on the definition of micro and macro-chronological time scales, and on asymptotic expansions of the unknown variables. First, the original anisotropic VE-VP initial-boundary value problem of the composite material is decomposed into coupled micro-chronological (fast time scale) and macro-chronological (slow time-scale) problems. The former is purely VE, and solved once for each macro time step, whereas the latter problem is nonlinear and solved iteratively using fully implicit time integration. Second, mean-field space homogenization is used for both micro and macro-chronological problems to determine the micro and macro-chronological effective behavior of the composite material. The response of the matrix material is VE-VP with J2 flow theory assuming small strains. The formulation exploits the return-mapping algorithm for the J2 model, with its two steps: viscoelastic predictor and plastic corrections. The proposal is implemented for an extended Mori-Tanaka scheme, and verified against finite element simulations of representative volume elements, for a number of polymer composite materials subjected to large numbers of cycles.

Keywords: asymptotic expansions, cyclic loadings, inclusion-reinforced thermoplastics, mean-field homogenization, time homogenization

Procedia PDF Downloads 339
1289 Study on the Wave Dissipation Performance of Double-Cylinder and Double-Plate Floating Breakwater

Authors: Liu Bijin

Abstract:

Floating breakwaters have several advantages, including being environmentally friendly, easy to construct, and cost-effective regardless of water depth. They have a broad range of applications in coastal engineering. However, they face significant challenges due to the unstable effect of wave dissipation, structural vulnerability, and high mooring system requirements. This paper investigates the wave dissipation performance of a floating breakwater structure. The structure consists of double cylinders, double vertical plates, and horizontal connecting plates. The investigation is carried out using physical model tests and numerical simulation methods based on STAR-CCM+. This paper discusses the impact of wave elements, relative vertical plate heights, and relative horizontal connecting plate widths on the wave dissipation performance of the double-cylinder, double-plate floating breakwater (DCDPFB). The study also analyses the changes in local vorticity and velocity fields around the DCDPFB to determine the optimal structural dimensions. The study found that the relative width of the horizontal connecting plate, the relative height of the vertical plate, and the size of the semi-cylinder are the key factors affecting the wave dissipation performance of the DCDPFB. The transmittance coefficient is minimally affected by the wave height and the depth of water entry. The local vortex and velocity field formed around the DCDPFB are important factors for dissipating wave energy. The test section of the DCDPFB, constructed according to the relative optimal structural dimensions, showed good wave dissipation performance during offshore prototype tests. The test section of DCDPFB, constructed with optimal structural dimensions, exhibits excellent wave dissipation performance in offshore prototype tests.

Keywords: floating breakwater, wave dissipation performance, transmittance coefficient, model test

Procedia PDF Downloads 18
1288 Quantification of River Ravi Pollution and Oxidation Pond Treatment to Improve the Drain Water Quality

Authors: Yusra Mahfooz, Saleha Mehmood

Abstract:

With increase in industrialization and urbanization, water contaminating rivers through effluents laden with diverse chemicals in developing countries. The study was based on the waste water quality of the four drains (Outfall, Gulshan -e- Ravi, Hudiara, and Babu Sabu) which enter into river Ravi in Lahore, Pakistan. Different pollution parameters were analyzed including pH, DO, BOD, COD, turbidity, EC, TSS, nitrates, phosphates, sulfates and fecal coliform. Approximately all the water parameters of drains were exceeded the permissible level of wastewater standards. In calculation of pollution load, Hudiara drains showed highest pollution load in terms of COD i.e. 429.86 tons/day while in Babu Sabu drain highest pollution load was calculated in terms of BOD i.e. 162.82 tons/day (due to industrial and sewage discharge in it). Lab scale treatment (oxidation ponds) was designed in order to treat the waste water of Babu Sabu drain, through combination of different algae species i.e. chaetomorphasutoria, sirogoniumsticticum and zygnema sp. Two different sizes of ponds (horizontal and vertical), and three different concentration of algal samples (25g/3L, 50g/3L, and 75g/3L) were selected. After 6 days of treatment, 80 to 97% removal efficiency was found in the pollution parameters. It was observed that in the vertical pond, maximum reduction achieved i.e. turbidity 62.12%, EC 79.3%, BOD 86.6%, COD 79.72%, FC 100%, nitrates 89.6%, sulphates 96.9% and phosphates 85.3%. While in the horizontal pond, the maximum reduction in pollutant parameters, turbidity 69.79%, EC 83%, BOD 88.5%, COD 83.01%, FC 100%, nitrates 89.8%, sulphates 97% and phosphates 86.3% was observed. Overall treatment showed that maximum reduction was carried out in 50g algae setup in the horizontal pond due to large surface area, after 6 days of treatment. Results concluded that algae-based treatment are most energy efficient, which can improve drains water quality in cost effective manners.

Keywords: oxidation pond, ravi pollution, river water quality, wastewater treatment

Procedia PDF Downloads 263
1287 Reduction of Biofilm Formation in Closed Circuit Cooling Towers

Authors: Irfan Turetgen

Abstract:

Closed-circuit cooling towers are cooling units that operate according to the indirect cooling principle. Unlike the open-loop cooling tower, the filler material includes a closed-loop water-operated heat exchanger. The main purpose of this heat exchanger is to prevent the cooled process water from contacting with the external environment. In order to ensure that the hot water is cooled, the water is cooled by the air flow and the circulation water of the tower as it passes through the pipe. They are now more commonly used than open loop cooling towers that provide cooling with plastic filling material. As with all surfaces in contact with water, there is a biofilm formation on the outer surface of the pipe. Although biofilm has been studied very well on plastic surfaces in open loop cooling towers, studies on biofilm layer formed on the heat exchangers of the closed circuit tower have not been found. In the recent study, natural biofilm formation was observed on the heat exchangers of the closed loop tower for 6 months. At the same time, nano-silica coating, which is known to reduce the formation of the biofilm layer, a comparison was made between the two different surfaces in terms of biofilm formation potential. Test surfaces were placed into biofilm reactor along with the untreated control coupons up to 6-months period for biofilm maturation. Natural bacterial communities were monitored to analyze the impact to mimic the real-life conditions. Surfaces were monthly analyzed in situ for their microbial load using epifluorescence microscopy. Wettability is known to play a key role in biofilm formation on surfaces, because characteristics of surface properties affect the bacterial adhesion. Results showed that surface-conditioning with nano-silica significantly reduce (up to 90%) biofilm formation. Easy coating process is a facile and low-cost method to prepare hydrophobic surface without any kinds of expensive compounds or methods.

Keywords: biofilms, cooling towers, fill material, nano silica

Procedia PDF Downloads 104
1286 Experimental Study of an Isobaric Expansion Heat Engine with Hydraulic Power Output for Conversion of Low-Grade-Heat to Electricity

Authors: Maxim Glushenkov, Alexander Kronberg

Abstract:

Isobaric expansion (IE) process is an alternative to conventional gas/vapor expansion accompanied by a pressure decrease typical of all state-of-the-art heat engines. The elimination of the expansion stage accompanied by useful work means that the most critical and expensive parts of ORC systems (turbine, screw expander, etc.) are also eliminated. In many cases, IE heat engines can be more efficient than conventional expansion machines. In addition, IE machines have a very simple, reliable, and inexpensive design. They can also perform all the known operations of existing heat engines and provide usable energy in a very convenient hydraulic or pneumatic form. This paper reports measurement made with the engine operating as a heat-to-shaft-power or electricity converter and a comparison of the experimental results to a thermodynamic model. Experiments were carried out at heat source temperature in the range 30–85 °C and heat sink temperature around 20 °C; refrigerant R134a was used as the engine working fluid. The pressure difference generated by the engine varied from 2.5 bar at the heat source temperature 40 °C to 23 bar at the heat source temperature 85 °C. Using a differential piston, the generated pressure was quadrupled to pump hydraulic oil through a hydraulic motor that generates shaft power and is connected to an alternator. At the frequency of about 0.5 Hz, the engine operates with useful powers up to 1 kW and an oil pumping flowrate of 7 L/min. Depending on the temperature of the heat source, the obtained efficiency was 3.5 – 6 %. This efficiency looks very high, considering such a low temperature difference (10 – 65 °C) and low power (< 1 kW). The engine’s observed performance is in good agreement with the predictions of the model. The results are very promising, showing that the engine is a simple and low-cost alternative to ORC plants and other known energy conversion systems, especially at low temperatures (< 100 °C) and low power range (< 500 kW) where other known technologies are not economic. Thus low-grade solar, geothermal energy, biomass combustion, and waste heat with a temperature above 30 °C can be involved into various energy conversion processes.

Keywords: isobaric expansion, low-grade heat, heat engine, renewable energy, waste heat recovery

Procedia PDF Downloads 186
1285 Application of Building Information Modelling In Analysing IGBC® Ratings (Sustainability Analyses)

Authors: Lokesh Harshe

Abstract:

The building construction sector is using 36% of global energy consumption with 39% of CO₂ emission. Professionals in the Built Environment Sector have long been aware of the industry’s contribution towards CO₂ emissions and are now moving towards more sustainable practices. As a result of this, many organizations have introduced rating systems to address the issue of global warming in the construction sector by ranking construction projects based on sustainability parameters. The pre-construction phase of any building project is the most essential time to make decisions for addressing the sustainability aspects. Traditionally, it is very difficult to collect data from different stakeholders and bring it together to form a decision based on factual data to perform sustainability analyses in the pre-construction phase. Building Information Modelling (BIM) is the solution where one single model is the result of the collaborative approach of BIM processes where all the information is shared, extracted, communicated, and stored on a single platform that everyone can access and make decisions based on real-time data. The focus of this research is on the Indian Green Rating System IGBC® with the objective of understanding IGBC® requirements and developing a framework to create the relationship between the rating processes and BIM. A Hypothetical (Architectural) model of a hostel building is developed using AutoCAD 2019 & Revit Arch. 2019, where the framework is applied to generate results on sustainability analysis using Green Building Studio (GBS) and Revit Add-ins. The results of any sustainability analysis are generated within a fraction of a minute, which is very quick in comparison with traditional sustainability analysis. This may save a considerable amount of time as well as cost. The future scope is to integrate Architectural, Structural, and MEP Models to perform accurate sustainability analyses with inputs from industry professionals working on real-life Green BIM projects.

Keywords: sustainability analyses, BIM, green rating systems, IGBC®, LEED

Procedia PDF Downloads 23
1284 Knowledge, Attitude, and Practice Related to Potential Application of Artificial Intelligence in Health Supply Chain

Authors: Biniam Bahiru Tufa, Hana Delil Tesfaye, Seife Demisse Legesse, Manaye Tamire

Abstract:

The healthcare industry is witnessing a digital transformation, with artificial intelligence (AI) offering potential solutions for challenges in health supply chain management (HSCM). However, the adoption of AI in this field remains limited. This research aimed to assess the knowledge, attitude, and practice of AI among students and employees in the health supply chain sector in Ethiopia. Using an explanatory case study research design with a concurrent mixed approach, quantitative and qualitative data were collected simultaneously. The study included 153 participants comprising students and employed health supply chain professionals working in various sectors. The majority had a pharmacy background, and one-third of the participants were male. Most respondents were under 35 years old, and around 68.6% had less than 10 years of experience. The findings revealed that 94.1% of participants had prior knowledge of AI, but only 35.3% were aware of its application in the supply chain. Moreover, the majority indicated that their training curriculum did not cover AI in health supply chain management. Participants generally held positive attitudes toward the necessity of AI for improving efficiency, effectiveness, and cost savings in the supply chain. However, many expressed concerns about its impact on job security and satisfaction, considering it as a burden Graduate students demonstrated higher knowledge of AI compared to employed staff, while graduate students also exhibited a more positive attitude toward AI. The study indicated low previous utilization and potential future utilization of AI in the health supply chain, suggesting untapped opportunities for improvement. Overall, while supply chain experts and graduate students lacked sufficient understanding of AI and its significance, they expressed favorable views regarding its implementation in the sector. The study recommends that the Ethiopian government and international organizations consider introducing AI in the undergraduate pharmacy curriculum and promote its integration into the health supply chain field.

Keywords: knowledge, attitude, practice, supply chain, articifial intellegence

Procedia PDF Downloads 62
1283 A Study on Improvement of the Torque Ripple and Demagnetization Characteristics of a PMSM

Authors: Yong Min You

Abstract:

The study on the torque ripple of Permanent Magnet Synchronous Motors (PMSMs) has been rapidly progressed, which effects on the noise and vibration of the electric vehicle. There are several ways to reduce torque ripple, which are the increase in the number of slots and poles, the notch of the rotor and stator teeth, and the skew of the rotor and stator. However, the conventional methods have the disadvantage in terms of material cost and productivity. The demagnetization characteristic of PMSMs must be attained for electric vehicle application. Due to rare earth supply issue, the demand for Dy-free permanent magnet has been increasing, which can be applied to PMSMs for the electric vehicle. Dy-free permanent magnet has lower the coercivity; the demagnetization characteristic has become more significant. To improve the torque ripple as well as the demagnetization characteristics, which are significant parameters for electric vehicle application, an unequal air-gap model is proposed for a PMSM. A shape optimization is performed to optimize the design variables of an unequal air-gap model. Optimal design variables are the shape of an unequal air-gap and the angle between V-shape magnets. An optimization process is performed by Latin Hypercube Sampling (LHS), Kriging Method, and Genetic Algorithm (GA). Finite element analysis (FEA) is also utilized to analyze the torque and demagnetization characteristics. The torque ripple and the demagnetization temperature of the initial model of 45kW PMSM with unequal air-gap are 10 % and 146.8 degrees, respectively, which are reaching a critical level for electric vehicle application. Therefore, the unequal air-gap model is proposed, and then an optimization process is conducted. Compared to the initial model, the torque ripple of the optimized unequal air-gap model was reduced by 7.7 %. In addition, the demagnetization temperature of the optimized model was also increased by 1.8 % while maintaining the efficiency. From these results, a shape optimized unequal air-gap PMSM has shown the usefulness of an improvement in the torque ripple and demagnetization temperature for the electric vehicle.

Keywords: permanent magnet synchronous motor, optimal design, finite element method, torque ripple

Procedia PDF Downloads 251