Search results for: advanced oxidation processes
1801 Water Infrastructure Asset Management: A Comparative Analysis of Three Urban Water Utilities in South Africa
Authors: Elkington S. Mnguni
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Water and sanitation services in South Africa are characterized by both achievements and challenges. After the end of apartheid in 1994 the newly elected government faced the challenge of eradicating backlogs with respect to access to basic services, including water and sanitation. Capital investment made in the development of new water and sanitation infrastructure to provide basic services to previously disadvantaged communities has grown, to a certain extent, at the expense of investment in the operation and maintenance of new and existing infrastructure. Challenges resulting from aging infrastructure and poor plant performance highlight the need for investing in the maintenance, rehabilitation, and replacement of existing infrastructure to optimize the return on investment. Advanced water infrastructure asset management (IAM) is key to achieving adequate levels of service, particularly with regard to reliable and high quality drinking water supply, prevention of urban flooding, efficient use of natural resources and prevention of pollution and associated risks. Against this backdrop, this paper presents an appraisal of water and sanitation IAM systems in South Africa’s three utilities, being metropolitan cities in the Gauteng Province. About a quarter of the national population lives in the three rapidly urbanizing cities of Johannesburg, Ekurhuleni and Tshwane, located in a semi-arid region. A literature review has been done and field visits to some of the utility facilities are being conducted. Semi-structured interviews will be conducted with the three utilities. The following critical factors are being analysed in terms of compliance with the national Water Services IAM Strategy (2011) and other applicable legislation: asset registers; capacity of assets; current and predicted demand; funding availability / budget allocations; plans: operation & maintenance, renewal & replacement, and risk management; no-drop status (non-revenue water levels); blue drop status (water quality); green drop status (effluent quality); and skills availability. Some of the key challenges identified in the literature review include: funding constraints, Skills shortage, and wastewater treatment plants operating beyond their design capacities. These challenges will be verified during field visits and research interviews. Gaps between literature and practice will be identified and relevant recommendations made if necessary. The objective of this study is to contribute to the resolution of the challenges brought about by the backlogs in the operation and maintenance of water and sanitation assets in the country in general, and in the three cities in particular, thus improving the sustainability thereof.Keywords: asset management, backlogs, levels of service, sustainability, water and sanitation infrastructure
Procedia PDF Downloads 2281800 The Promotion of Andalusian Heritage through Tourism in the Medina of Marrakech
Authors: Nour Eddine Nachouane, Aicha Knidiri
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The Hispano-Moorish art was born in 786 when Abd ar-Rahman built the first mosque in Cordoba. It is a still-living art in the trades of the big Moroccan cities. Everyone agrees that the different artistic forms of Arab-Muslim art find their full development in traditional Moroccan architecture, and this heritage allows artists and artisans to create magnificent masterpieces. Marrakech, by way of example, constitutes a symbolic city, which represents the reflection of a rich history of this art carried by a long artisanal tradition that is still living nowadays. Despite its ratification by UNESCO as intangible cultural heritage, and beyond official speeches, several of those craft trades are endangered, and with them the whole history of millennial savoir-faire. From the empirical study of the old historic center, 'the medina' of Marrakech, we explore in this article the opportunity offered by the tourism industry in order to protect these craft trades. We question artisans on the evolution of the sector and the challenges of the transmission of this heritage. We evoke the case of Spanish cities like Granada in a comparative reflection on the strategies and perceptions of the public administrations of a part, and, on the other hand, on the shared experience of artisans and tourists. In an interdisciplinary approach mixing anthropology, history, sociology, and even geography, we question the capacity of heritage processes to mobilize and involve a set of actors and activate a trajectory for the safeguarding of Andalusian arts and techniques. The basic assumption of this research is that the promotion of traditional craft trades through tourism and based on good scientific knowledge can present an original offer to cope with globalization and guarantee the transmission of that savoir-faire to new generations. Research in the field of Islamic arts does not constitute a retreat into the nationalist identity or a fixation on the past but an opening towards cultural diversity, free from any standardization.Keywords: heritage, art andalusi, handcraft, tourism
Procedia PDF Downloads 1631799 Challenges in Achieving Profitability for MRO Companies in the Aviation Industry: An Analytical Approach
Authors: Nur Sahver Uslu, Ali̇ Hakan Büyüklü
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Maintenance, Repair, and Overhaul (MRO) costs are significant in the aviation industry. On the other hand, companies that provide MRO services to the aviation industry but are not dominant in the sector, need to determine the right strategies for sustainable profitability in a competitive environment. This study examined the operational real data of a small medium enterprise (SME) MRO company where analytical methods are not widely applied. The company's customers were divided into two categories: airline companies and non-airline companies, and the variables that best explained profitability were analyzed with Logistic Regression for each category and the results were compared. First, data reduction was applied to the transformed variables that went through the data cleaning and preparation stages, and the variables to be included in the model were decided. The misclassification rates for the logistic regression results concerning both customer categories are similar, indicating consistent model performance across different segments. Less profit margin is obtained from airline customers, which can be explained by the variables part description, time to quotation (TTQ), turnaround time (TAT), manager, part cost, and labour cost. The higher profit margin obtained from non-airline customers is explained only by the variables part description, part cost, and labour cost. Based on the two models, it can be stated that it is significantly more challenging for the MRO company, which is the subject of our study, to achieve profitability from Airline customers. While operational processes and organizational structure also affect the profit from airline customers, only the type of parts and costs determine the profit for non-airlines.Keywords: aircraft, aircraft components, aviation, data analytics, data science, gini index, maintenance, repair, and overhaul, MRO, logistic regression, profit, variable clustering, variable reduction
Procedia PDF Downloads 331798 The Formation of Thin Copper Films on Graphite Surface Using Magnetron Sputtering Method
Authors: Zydrunas Kavaliauskas, Aleksandras Iljinas, Liutauras Marcinauskas, Mindaugas Milieska, Vitas Valincius
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The magnetron sputtering deposition method is often used to obtain thin film coatings. The main advantage of magnetron vaporization compared to other deposition methods is the high rate erosion of the cathode material (e.g., copper, aluminum, etc.) and the ability to operate under low-pressure conditions. The structure of the formed coatings depends on the working parameters of the magnetron deposition system, which is why it is possible to influence the properties of the growing film, such as morphology, crystal orientation, and dimensions, stresses, adhesion, etc. The properties of these coatings depend on the distance between the substrate and the magnetron surface, the vacuum depth, the gas used, etc. Using this deposition technology, substrates are most often placed near the anode. The magnetic trap of the magnetrons for localization of electrons in the cathode region is formed using a permanent magnet system that is on the side of the cathode. The scientific literature suggests that, after insertion of a small amount of copper into graphite, the electronic conductivity of graphite increase. The aim of this work is to create thin (up to 300 nm) layers on a graphite surface using a magnetron evaporation method, to investigate the formation peculiarities and microstructure of thin films, as well as the mechanism of copper diffusion into graphite inner layers at different thermal treatment temperatures. The electron scanning microscope was used to investigate the microrelief of the coating surface. The chemical composition is determined using the EDS method, which shows that, with an increase of the thermal treatment of the copper-carbon layer from 200 °C to 400 °C, the copper content is reduced from 8 to 4 % in atomic mass units. This is because the EDS method captures only the amount of copper on the graphite surface, while the temperature of the heat treatment increases part of the copper because of the diffusion processes penetrates into the inner layers of the graphite. The XRD method shows that the crystalline copper structure is not affected by thermal treatment.Keywords: carbon, coatings, copper, magnetron sputtering
Procedia PDF Downloads 2901797 Generic Competences, the Great Forgotten: Teamwork in the Undergraduate Degree in Translation and Interpretation
Authors: María-Dolores Olvera-Lobo, Bryan John Robinson, Juncal Gutierrez-Artacho
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Graduates are equipped with a wide range of generic competencies which complement solid curricular competencies and facilitate their access to the labour market in diverse fields and careers. However, some generic competencies such as instrumental, personal and systemic competencies related to teamwork and interpersonal communication skills, decision-making and organization skills are seldom taught explicitly and even less often assessed. In this context, translator training has embraced a broad range of competencies specified in the undergraduate program currently taught at universities and opens up the learning experience to cover areas often ignored due to the difficulties inherent in both teaching and assessment. In practice, translator training combines two well-established approaches to teaching/learning: project-based learning and genuinely cooperative – or merely collaborative – learning. Our professional approach to translator training is a model focused on and adapted to the teleworking context of professional translation and presented through the medium of blended e-learning. Teamwork-related competencies are extremely relevant, and they require explicit and implicit teaching so that graduates can be confident about their capacity to make their way in professional contexts. In order to highlight the importance of teamwork and intra-team relationships beyond the classroom, we aim to raise awareness of teamwork processes so as to empower translation students in managing their interaction and ensure that they gain valuable pre-professional experience. With these objectives, at the University of Granada (Spain) we have developed a range of classroom activities and assessment tools. The results of their application are summarized in this study.Keywords: blended learning, collaborative teamwork, cross-curricular competencies, higher education, intra-team relationships, students’ perceptions, translator training
Procedia PDF Downloads 1691796 Removal of Rhodamine B from Aqueous Solution Using Natural Clay by Fixed Bed Column Method
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The discharge of dye in industrial effluents is of great concern because their presence and accumulation have a toxic or carcinogenic effect on living species. The removal of such compounds at such low levels is a difficult problem. The adsorption process is an effective and attractive proposition for the treatment of dye contaminated wastewater. Activated carbon adsorption in fixed beds is a very common technology in the treatment of water and especially in processes of decolouration. However, it is expensive and the powdered one is difficult to be separated from aquatic system when it becomes exhausted or the effluent reaches the maximum allowable discharge level. The regeneration of exhausted activated carbon by chemical and thermal procedure is also expensive and results in loss of the sorbent. The focus of this research was to evaluate the adsorption potential of the raw clay in removing rhodamine B from aqueous solutions using a laboratory fixed-bed column. The continuous sorption process was conducted in this study in order to simulate industrial conditions. The effect of process parameters, such as inlet flow rate, adsorbent bed height, and initial adsorbate concentration on the shape of breakthrough curves was investigated. A glass column with an internal diameter of 1.5 cm and height of 30 cm was used as a fixed-bed column. The pH of feed solution was set at 8.5. Experiments were carried out at different bed heights (5 - 20 cm), influent flow rates (1.6- 8 mL/min) and influent rhodamine B concentrations (20 - 80 mg/L). The obtained results showed that the adsorption capacity increases with the bed depth and the initial concentration and it decreases at higher flow rate. The column regeneration was possible for four adsorption–desorption cycles. The clay column study states the value of the excellent adsorption capacity for the removal of rhodamine B from aqueous solution. Uptake of rhodamine B through a fixed-bed column was dependent on the bed depth, influent rhodamine B concentration, and flow rate.Keywords: adsorption, breakthrough curve, clay, fixed bed column, rhodamine b, regeneration
Procedia PDF Downloads 2751795 Conditions That Brought Bounce-Back in Southern Europe: An Inter-Temporal and Cross-National Analysis on Female Labour Force Participation with Fuzzy Set Qualitative Comparative Analysis
Authors: A. Onur Kutlu, H. Tolga Bolukbasi
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Since the 1990s, governments, international organizations and scholars have drawn increasing attention to the significance of women in the labour force. While advanced industrial countries in North Western Europe and North America have managed to increase female labour force participation (FLFP) in the early post world war two period, emerging economies of the 1970s have only been able to increase FLFP only a decade later. Among these areas, Southern Europe features a wave of remarkable bounce backs in FLFP. However, despite striking similarities between the features in Southern Europe and those in Turkey, Turkey has not been able to pull women into the labour force. Despite a host of institutional similarities, Turkey has failed to reach to the level of her Southern European neighbours. This paper addresses the puzzle why Turkey lag behind in FLFP in comparison to her Southern European neighbours. There are signs showing that FLFP is currently reaching a critical threshold at a time when structural factors may allow a trend. It is not known, however, the constellation of conditions which may bring rising FLFP in Turkey. In order to gain analytical leverage from similar transitions in countries that share similar labour market and welfare state regime characteristics, this paper identifies the conditions in Southern Europe that brought rising FLFP to be able to explore the prospects for Turkey. Second, this paper takes these variables in the fuzzy set Qualitative Comparative Analysis (fsQCA) as conditions which can potentially explain the outcome of rising FLFP in Portugal, Spain, Italy, Greece and Turkey. The purpose here is to identify any causal pathway there may exist that lead to rising FLFP in Southern Europe. In order to do so, this study analyses two time periods in all cases, which represent different periods for different countries. The first period is identified on the basis of low FLFP and the second period on the basis of the transition to significantly higher FLFP. Third, the conditions are treated following the standard procedures in fsQCA, which provide equifinal: two distinct paths to higher levels of FLFP in Southern Europe, each of which may potentially increase FLFP in Turkey. Based on this analysis, this paper proposes that there exist two distinct paths leading to higher levels of FLFP in Southern Europe. Among these paths, salience of left parties emerges as a sufficient condition. In cases where this condition was not present, a second path combining enlarging service sector employment, increased tertiary education among women and increased childcare enrolment rates led to increasing FLFP.Keywords: female labour force participation, fsQCA, Southern Europe, Turkey
Procedia PDF Downloads 3261794 Beyond Empathy: From Justice to Reconciliation
Authors: Nissim Avissar
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This paper aims to question the practice of bringing together people belonging to groups in conflict with the aim of bridging differences through universal empathy and interpersonal connections. It is argued that in cases where one group has the power, and the other is in a struggle to change the balance assuming universal equality between the groups and encouraging emphatic understanding is a non-emphatic practice. Accordingly, a new concept is posited–justice-sensitive empathy, conditioning empathy in such situations on the acknowledgement of an imbalance of power/injustice. With this reframing in mind, educational practices promoting social justice are discussed. In order to create conditions for justice-seeking or politically sensitive empathy, we need to go beyond the conventional definitions of empathy and offer other means and possibilities. Three possibilities are discussed. The first focuses on intra-group (as opposed to inter-group) processes within each group. It means temporary and tactical separation that may allow each group to focus on its own needs and values and perhaps to return to the dialogue more confidently. The second option emphasizes the notion of "constructive conflict," which means that each side still aspires to promote his own interests but without demolishing the other side (which is a rival but also an unwanted and forced partner). Here, alongside the "obligation to resist" and to act to promote justice as we view and understand it, we have to take into account the other side. The third and last option relates to the practice of Restorative Justice. This practice originated in the Truth and Reconciliation committees in South Africa, but it is now widely used in other contexts. Those committees had the authority to punish (or pardon) people; however, their main purpose was to seek truth and, from there, nourish reconciliation. This is the main idea of restorative justice; it seeks justice for the sake of restoring relationships. All the above options involve action and are aware of power relations (i.e., politics). They all seek justice. They may create conditions for the more conventional empathic practice to evolve, but no less than that, they are examples of justice-seeking and politically sensitive empathetic practice.Keywords: education, empathy, justice, reconciliation
Procedia PDF Downloads 971793 Phylogenetic Relationships between the Whole Sets of Individual Flow Sorted U, M, S and C Chromosomes of Aegilops and Wheat as Revealed by COS Markers
Authors: András Farkas, István Molnár, Jan Vrána, Veronika Burešová, Petr Cápal, András Cseh, Márta Molnár-Láng, Jaroslav Doležel
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Species of Aegilops played a central role in the evolution of wheat and are sources of traits related to yield quality and tolerance against biotic and abiotic stresses. These wild genes and alleles are desirable to use in crop improvement programs via introgressive hybridization. However, the success of chromosome mediated gene transfer to wheat are hampered by the pour knowledge on the genome structure of Aegilops relative to wheat and by the low number of cost-effective molecular markers specific for Aegilops chromosomes. The COS markers specific for genes conserved throughout evolution in both sequence and copy number between Triticeae/Aegilops taxa and define orthologous regions, thus enabling the comparison of regions on the chromosomes of related species. The present study compared individual chromosomes of Aegilops umbellulata (UU), Ae. comosa (MM), Ae. speltoides (SS) and Ae. caudata (CC) purified by flourescent labelling with oligonucleotid SSR repeats and biparametric flow cytometry with wheat by identifying orthologous chromosomal regions by COS markers. The linear order of bin-mapped COS markers along the wheat D chromosomes was identified by the use of chromosome-specific sequence data and virtual gene order. Syntenic regions of wheat identifying genome rearrangements differentiating the U, M, S or C genomes from the D genome of wheat were detected. The conserved orthologous set markers assigned to Aegilops chromosomes promise to accelerate gene introgression by facilitating the identification of alien chromatin. The syntenic relationships between the Aegilops species and wheat will facilitate the targeted development of new markers specific for U, M, S and C genomic regions and will contribute to the understanding of molecular processes related to the evolution of Aegilops.Keywords: Aegilops, cos-markers, flow-sorting, wheat
Procedia PDF Downloads 5021792 Reality Shock Affecting the Motivation to Work of New Flight Attendants: An Exploratory Qualitative Study of Flight Attendants Who Left Their Jobs Early
Authors: Hiromi Takafuji
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Flight attendant:FA is one of popular occupation, especially in Asian countries, and the decision to be hired is made after clearing a high multiplier. On the other hand, immediately after joining the company, they experience unique stress due to the fact that the organization requires them to perform security and customer service duties in a highly specialized and limited space and time. As a result, despite the high level of difficulty in joining the company, many new recruits retire early at a high rate. It is commonly said that 30% of new graduates leave the company within three years in Japan and speculated that Reality Shock:RS is one of the causes of this. RS is that newcomers experience refers to the stress caused by the difference between pre-employment expectations and post-employment reality. The purpose of this study was to elucidate the mechanism by which the expertise required of new FA and the expectation of expertise held by each of them cause reality shock, which affects motivation and the decision to leave. This study identified the professionalism required of new FA and the impact of that expectation for professionalism on RS through an exploratory study of the experiences and psychological processes of FA who left within three years. Semi-structured in-depth interviews were conducted with five FA who left a major Japanese airline at an early stage, and their experiences were categorized, integrated, and classified by qualitative content analysis. They were chosen under a number of controlled conditions. Then two major findings emerged: first, that pre-employment expectations defining RS were hierarchical, and second, that training amplified expectations of professionalism, which strongly influenced early turnover. From these, this study generated a model of RS generative process model of FA that expectations are hierarchical and influential. This could contribute to the prevention of mental health deterioration by reality shock among new FA.Keywords: reality shock, flight attendant, early turnover, qualitative study
Procedia PDF Downloads 821791 Rejuvenation of Aged Kraft-Cellulose Insulating Paper Used in Transformers
Authors: Y. Jeon, A. Bissessur, J. Lin, P. Ndungu
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Most transformers employ the usage of cellulose paper, which has been chemically modified through the Kraft process that acts as an effective insulator. Cellulose ageing and oil degradation are directly linked to fouling of the transformer and accumulation of large quantities of waste insulating paper. In addition to technical difficulties, this proves costly for power utilities to deal with. Currently there are no cost effective method for the rejuvenation of cellulose paper that has been documented nor proposed, since renewal of used insulating paper is implemented as the best option. This study proposes and contrasts different rejuvenation methods of accelerated aged cellulose insulating paper by chemical and bio-bleaching processes. Of the three bleaching methods investigated, two are, conventional chlorine-based sodium hypochlorite (m/v), and chlorine-free hydrogen peroxide (v/v), whilst the third is a bio-bleaching technique that uses a bacterium isolate, Acinetobacter strain V2. Through chemical bleaching, varying the strengths of the bleaching reagents at 0.3 %, 0.6 %, 0.9 %, 1.2 %, 1.5 % and 1.8 % over 4 hrs. were analyzed. Bio-bleaching implemented a bacterium isolate, Acinetobacter strain V2, to bleach the aged Kraft paper over 4 hrs. The determination of the amount of alpha cellulose, degree of polymerization and viscosity carried out on Kraft-cellulose insulating paper before and after bleaching. Overall the investigated techniques of chemical and bio-bleaching were successful and effective in treating degraded and accelerated aged Kraft-cellulose insulating paper, however, to varying extents. Optimum conditions for chemical bleaching were attained at bleaching strengths of 1.2 % (m/v) NaOCl and 1.5 % (v/v) H2O2 yielding alpha cellulose contents of 82.4 % and 80.7 % and degree of polymerizations of 613 and 616 respectively. Bio-bleaching using Acinetobacter strain V2 proved to be the superior technique with alpha cellulose levels of 89.0 % and a degree of polymerization of 620. Chemical bleaching techniques require careful and controlled clean-up treatments as it is chlorine and hydrogen peroxide based while bio-bleaching is an extremely eco-friendly technique.Keywords: alpha cellulose, bio-bleaching, degree of polymerization, Kraft-cellulose insulating paper, transformer, viscosity
Procedia PDF Downloads 2701790 Taguchi Robust Design for Optimal Setting of Process Wastes Parameters in an Automotive Parts Manufacturing Company
Authors: Charles Chikwendu Okpala, Christopher Chukwutoo Ihueze
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As a technique that reduces variation in a product by lessening the sensitivity of the design to sources of variation, rather than by controlling their sources, Taguchi Robust Design entails the designing of ideal goods, by developing a product that has minimal variance in its characteristics and also meets the desired exact performance. This paper examined the concept of the manufacturing approach and its application to brake pad product of an automotive parts manufacturing company. Although the firm claimed that only defects, excess inventory, and over-production were the few wastes that grossly affect their productivity and profitability, a careful study and analysis of their manufacturing processes with the application of Single Minute Exchange of Dies (SMED) tool showed that the waste of waiting is the fourth waste that bedevils the firm. The selection of the Taguchi L9 orthogonal array which is based on the four parameters and the three levels of variation for each parameter revealed that with a range of 2.17, that waiting is the major waste that the company must reduce in order to continue to be viable. Also, to enhance the company’s throughput and profitability, the wastes of over-production, excess inventory, and defects with ranges of 2.01, 1.46, and 0.82, ranking second, third, and fourth respectively must also be reduced to the barest minimum. After proposing -33.84 as the highest optimum Signal-to-Noise ratio to be maintained for the waste of waiting, the paper advocated for the adoption of all the tools and techniques of Lean Production System (LPS), and Continuous Improvement (CI), and concluded by recommending SMED in order to drastically reduce set up time which leads to unnecessary waiting.Keywords: lean production system, single minute exchange of dies, signal to noise ratio, Taguchi robust design, waste
Procedia PDF Downloads 1261789 3-D Modeling of Particle Size Reduction from Micro to Nano Scale Using Finite Difference Method
Authors: Himanshu Singh, Rishi Kant, Shantanu Bhattacharya
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This paper adopts a top-down approach for mathematical modeling to predict the size reduction from micro to nano-scale through persistent etching. The process is simulated using a finite difference approach. Previously, various researchers have simulated the etching process for 1-D and 2-D substrates. It consists of two processes: 1) Convection-Diffusion in the etchant domain; 2) Chemical reaction at the surface of the particle. Since the process requires analysis along moving boundary, partial differential equations involved cannot be solved using conventional methods. In 1-D, this problem is very similar to Stefan's problem of moving ice-water boundary. A fixed grid method using finite volume method is very popular for modelling of etching on a one and two dimensional substrate. Other popular approaches include moving grid method and level set method. In this method, finite difference method was used to discretize the spherical diffusion equation. Due to symmetrical distribution of etchant, the angular terms in the equation can be neglected. Concentration is assumed to be constant at the outer boundary. At the particle boundary, the concentration of the etchant is assumed to be zero since the rate of reaction is much faster than rate of diffusion. The rate of reaction is proportional to the velocity of the moving boundary of the particle. Modelling of the above reaction was carried out using Matlab. The initial particle size was taken to be 50 microns. The density, molecular weight and diffusion coefficient of the substrate were taken as 2.1 gm/cm3, 60 and 10-5 cm2/s respectively. The etch-rate was found to decline initially and it gradually became constant at 0.02µ/s (1.2µ/min). The concentration profile was plotted along with space at different time intervals. Initially, a sudden drop is observed at the particle boundary due to high-etch rate. This change becomes more gradual with time due to declination of etch rate.Keywords: particle size reduction, micromixer, FDM modelling, wet etching
Procedia PDF Downloads 4311788 Investigation of the Factors Influencing the Construction Planning Process Using Participant Observation Method
Authors: Ashokkumar Subbiah
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This study investigates the impact of factors that influenced the success of construction planning for a major construction project in Qatar. An approach of participant observation is adopted which is informed by the principles of ethnography: one that reports the participants’ view of their world rather than imposing an artificial theoretical framework upon it. As participant observant, key factors were observed and identified that had an impact on the management and execution of the construction planning. It is found that a ‘shadow culture’ exists between the project participants which, it is argued, is only observable from the perspective of an embedded participant observer. The shadow culture acts to enable the management of the planning process, and its efficacy relates to the ‘quality’ of human inter-relationships amongst immediate stakeholders. Whilst this study uses the concept of shadow culture, it is treated as both a methodological stance and one of the findings of this research in the context of the major construction project in Qatar. The concept of shadow culture is not imposed upon the findings, but instead is used as a research tool: respondents report their own worldview and this is reported from the view of a participant observant in a manner that is understandable and useful to those who are not part of the construction project. The findings of this study identify similar factors influencing the planning process of the Qatar project, but the shadow culture predominantly influences these factors towards the failure of planning process. The research concludes by questioning the assumption that construction planning is a mechanistic process that has to be conducted solely by the planning team. Instead, it is a highly social phenomenon in which the seemingly mechanistic process is made workable by the quality of relationships that exist in the project. Drawing on this the final section provides a series of recommendations that may be helpful in enhancing the efficacy of project planning; these include better training/education at the pre-construction phase; recognition of the importance of shadow processes at management levels, and better appreciation of the impact of contract type and chosen procurement route.Keywords: construction planning, participant observation, project participants, shadow culture
Procedia PDF Downloads 2981787 Analysis of Superconducting and Optical Properties in Atomic Layer Deposition and Sputtered Thin Films for Next-Generation Single-Photon Detectors
Authors: Nidhi Choudhary, Silke A. Peeters, Ciaran T. Lennon, Dmytro Besprozvannyy, Harm C. M. Knoops, Robert H. Hadfield
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Superconducting Nanowire Single Photon Detectors (SNSPDs) have become leading devices in quantum optics and photonics, known for their exceptional efficiency in detecting single photons from ultraviolet to mid-infrared wavelengths with minimal dark counts, low noise, and reduced timing jitter. Recent advancements in materials science focus attention on refractory metal thin films such as NbN and NbTiN to enhance the optical properties and superconducting performance of SNSPDs, opening the way for next-generation detectors. These films have been deposited by several different techniques, such as atomic layer deposition (ALD), plasma pro-advanced plasma processing (ASP) and magnetron sputtering. The fabrication flexibility of these films enables precise control over morphology, crystallinity, stoichiometry and optical properties, which is crucial for optimising the SNSPD performance. Hence, it is imperative to study the optical and superconducting properties of these materials across a wide range of wavelengths. This study provides a comprehensive analysis of the optical and superconducting properties of some important materials in this category (NbN, NbTiN) by different deposition methods. Using Variable angle ellipsometry spectroscopy (VASE), we measured the refractive index, extinction, and absorption coefficient across a wide wavelength range (200-1700 nm) to enhance light confinement for optical communication devices. The critical temperature and sheet resistance were measured using a four-probe method in a custom-built, cryogen-free cooling system with a Sumitomo RDK-101D cold head and CNA-11C compressor. Our results indicate that ALD-deposited NbN shows a higher refractive index and extinction coefficient in the near-infrared region (~1500 nm) than sputtered NbN of the same thickness. Further, the analysis of the optical properties of plasma pro-ASP deposited NbTiN was performed at different substrate bias voltages and different thicknesses. The analysis of substrate bias voltage indicates that the maximum value of the refractive index and extinction coefficient observed for the substrate biasing of 50-80 V across a substrate bias range of (0 V - 150 V). The optical properties of sputtered NbN films are also investigated in terms of the different substrate temperatures during deposition (100 °C-500 °C). We find the higher the substrate temperature during deposition, the higher the value of the refractive index and extinction coefficient has been observed. In all our superconducting thin films ALD-deposited NbN films possess the highest critical temperature (~12 K) compared to sputtered (~8 K) and plasma pro-ASP (~5 K).Keywords: optical communication, thin films, superconductivity, atomic layer deposition (ALD), niobium nitride (NbN), niobium titanium nitride (NbTiN), SNSPD, superconducting detector, photon-counting.
Procedia PDF Downloads 291786 Holistic Solutions for Overcoming Fluoride Contamination Challenges in West Bengal, India: A Socio-economic Study on Water Quality, Infrastructure, and Community Engagement
Authors: Rajkumar Ghosh, Shyama Pada Gorai
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Access to safe drinking water is a fundamental human right; however, regions like Purulia, Bankura, Birbhum, Malda, Dinajpur in West Bengal, India, face formidable challenges due to heightened fluoride levels. This paper delves into the hurdles of fresh drinking water production, presenting comprehensive solutions derived from literature reviews, field surveys, and scientific analyses. Encompassing fluoride-affected areas in Purulia, Bankura, Birbhum, Malda, North-South Dinajpur, and South 24 Parganas, the study emphasizes an integrated and sustainable approach. Employing a multidisciplinary methodology, combining scientific analysis and community engagement, the study identifies key factors influencing water quality and proposes sustainable strategies. Elevated fluoride concentrations exceeding international health standards (Purulia: 0.126 – 8.16 mg/L, Bankura: 0.1 – 12.2 mg/L, Malda: 0.1 – 4.54 mg/L, Birbhum: 0.023 – 18 mg/L) necessitate urgent intervention. Infrastructure deficiencies impede water treatment and distribution, while limited awareness obstructs community participation. The proposed solutions embrace advanced water treatment technologies, infrastructure development, community education, and sustainable water management practices. This comprehensive effort aims to provide clean drinking water, safeguarding the health of affected populations. Building on these foundations, the study explores the potential of rooftop rainwater harvesting as an effective and sustainable strategy to mitigate challenges in fresh drinking water production. By addressing fluoride contamination concerns and promoting community involvement, this approach presents a holistic solution to water quality issues in affected regions. The findings underscore the importance of integrating sustainable practices with community engagement to achieve long-term water security in Purulia, Bankura, Birbhum, Malda, North-South Dinajpur, and South 24 Parganas. This study serves as a cornerstone for further research and policy development, addressing fluoride contamination's impact on public health in affected areas. Recommendations include the establishment of long-term monitoring programs to assess the effectiveness of implemented solutions and conducting health impact studies to understand the long-term effects of fluoride contamination on the local population.Keywords: fluoride mitigation, rainwater harvesting, water quality, sustainable water management, community engagement
Procedia PDF Downloads 721785 Evaluation of the Impact of Community Based Disaster Risk Management Applied In Landslide Prone Area; Reference to Badulla District
Authors: S. B. D. Samarasinghe, Malini Herath
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Participatory planning is a very important process for decision making and choosing the best alternative options for community welfare, development of the society and its interactions among community and professionals. People’s involvement is considered as the key guidance in participatory planning. Presently, Participatory planning is being used in many fields. It's not only limited to planning but also to disaster management, poverty, housing, etc. In the past, Disaster management practice was a top-down approach, but it raised many issues as it was converted to a bottom-up approach. There are several approaches that can aid disaster management. Community-Based Disaster Risk Management (CBDRM) is a very successful participatory approach to risk management that is often successfully applied by other disaster-prone countries. In the local context, CBDRM has been applied to prevent Diseases as well as to prevent disasters such as landslides, tsunamis and floods. From three years before, Sri Lanka has initiated the CBDRM approach to minimize landslide vulnerability. Hence, this study mainly focuses on the impact of CBDRM approaches on landslide hazards. Also to identify their successes and failures from both implementing parties and community. This research is carried out based on a qualitative method combined with a descriptive research approach. A successful framework was prepared via a literature review. Case studies were selected considering landslide CBDRM programs which were implemented by Disaster Management Center and National Building Research Organization in Badulla. Their processes were evaluated. Data collection is done through interviews and informal discussions. Then their ideas were quantified by using the Relative Effectiveness index. The resulting numerical value was used to rank the program effectiveness and their success, failures and impacting factors. Results show that there are several failures among implementing parties and the community. Overcoming those factors can make way for better conduction of future CBDRM programs.Keywords: community-based disaster risk management, disaster management, preparedness, landslide
Procedia PDF Downloads 1471784 Integrating Dependent Material Planning Cycle into Building Information Management: A Building Information Management-Based Material Management Automation Framework
Authors: Faris Elghaish, Sepehr Abrishami, Mark Gaterell, Richard Wise
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The collaboration and integration between all building information management (BIM) processes and tasks are necessary to ensure that all project objectives can be delivered. The literature review has been used to explore the state of the art BIM technologies to manage construction materials as well as the challenges which have faced the construction process using traditional methods. Thus, this paper aims to articulate a framework to integrate traditional material planning methods such as ABC analysis theory (Pareto principle) to analyse and categorise the project materials, as well as using independent material planning methods such as Economic Order Quantity (EOQ) and Fixed Order Point (FOP) into the BIM 4D, and 5D capabilities in order to articulate a dependent material planning cycle into BIM, which relies on the constructability method. Moreover, we build a model to connect between the material planning outputs and the BIM 4D and 5D data to ensure that all project information will be accurately presented throughout integrated and complementary BIM reporting formats. Furthermore, this paper will present a method to integrate between the risk management output and the material management process to ensure that all critical materials are monitored and managed under the all project stages. The paper includes browsers which are proposed to be embedded in any 4D BIM platform in order to predict the EOQ as well as FOP and alarm the user during the construction stage. This enables the planner to check the status of the materials on the site as well as to get alarm when the new order will be requested. Therefore, this will lead to manage all the project information in a single context and avoid missing any information at early design stage. Subsequently, the planner will be capable of building a more reliable 4D schedule by allocating the categorised material with the required EOQ to check the optimum locations for inventory and the temporary construction facilitates.Keywords: building information management, BIM, economic order quantity, EOQ, fixed order point, FOP, BIM 4D, BIM 5D
Procedia PDF Downloads 1721783 Impact of Water Storage Structures on Groundwater Recharge in Jeloula Basin, Central Tunisia
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An attempt has been made to examine the effect of water storage structures on groundwater recharge in a semi-arid agroclimatic setting in Jeloula Basin (Central Tunisia). In this area, surface water in rivers is seasonal, and therefore groundwater is the perennial source of water supply for domestic and agricultural purposes. Three pumped storage water power plants (PSWPP) have been built to increase the overall water availability in the basin and support agricultural livelihoods of rural smallholders. The scale and geographical dispersion of these multiple lakes restrict the understanding of these coupled human-water systems and the identification of adequate strategies to support riparian farmers. In the present review, hydrochemistry and isotopic tools were combined to get an insight into the processes controlling mineralization and recharge conditions in the investigated aquifer system. This study showed a slight increase in the groundwater level, especially after the artificial recharge operations and a decline when the water volume moves down during drought periods. Chemical data indicate that the main sources of salinity in the waters are related to water-rock interactions. Data inferred from stable isotopes in groundwater samples indicated recharge with modern rainfall. The investigated surface water samples collected from the PSWPP are affected by a significant evaporation and reveal large seasonal variations, which could be controlled by the water volume changes in the open surface reservoirs and the meteorological conditions during evaporation, condensation, and precipitation. The geochemical information is comparable to the isotopic results and illustrates that the chemical and isotopic signatures of reservoir waters differ clearly from those of groundwaters. These data confirm that the contribution of the artificial recharge operations from the PSWPP is very limited.Keywords: Jeloula basin, recharge, hydrochemistry, isotopes
Procedia PDF Downloads 1521782 Development of Innovative Nuclear Fuel Pellets Using Additive Manufacturing
Authors: Paul Lemarignier, Olivier Fiquet, Vincent Pateloup
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In line with the strong desire of nuclear energy players to have ever more effective products in terms of safety, research programs on E-ATF (Enhanced-Accident Tolerant Fuels) that are more resilient, particularly to the loss of coolant, have been launched in all countries with nuclear power plants. Among the multitude of solutions being developed internationally, carcinoembryonic antigen (CEA) and its partners are investigating a promising solution, which is the realization of CERMET (CERamic-METal) type fuel pellets made of a matrix of fissile material, uranium dioxide UO2, which has a low thermal conductivity, and a metallic phase with a high thermal conductivity to improve heat evacuation. Work has focused on the development by powder metallurgy of micro-structured CERMETs, characterized by networks of metallic phase embedded in the UO₂ matrix. Other types of macro-structured CERMETs, based on concepts proposed by thermal simulation studies, have been developed with a metallic phase with a specific geometry to optimize heat evacuation. This solution could not be developed using traditional processes, so additive manufacturing, which revolutionizes traditional design principles, is used to produce these innovative prototype concepts. At CEA Cadarache, work is first carried out on a non-radioactive surrogate material, alumina, in order to acquire skills and to develop the equipment, in particular the robocasting machine, an additive manufacturing technique selected for its simplicity and the possibility of optimizing the paste formulations. A manufacturing chain was set up, with the pastes production, the 3D printing of pellets, and the associated thermal post-treatment. The work leading to the first elaborations of macro-structured alumina/molybdenum CERMETs will be presented. This work was carried out with the support of Framatome and EdF.Keywords: additive manufacturing, alumina, CERMET, molybdenum, nuclear safety
Procedia PDF Downloads 771781 Digital Governance Decision-Making in the Aftermath of Cybersecurity Crises, Lessons from Estonia
Authors: Logan Carmichael
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As the world’s governments seek to increasingly digitize their service provisions, there exists a subsequent and fully valid concern about the security underpinning these digital governance provisions. Estonia, a small and innovative Baltic nation, has been refining both its digital governance structure and cybersecurity mechanisms for over three decades and has been praised as global ‘best practice’ in both fields. However, the security of the Estonian digital governance system has been ever-evolving and significantly shaped by cybersecurity crises. This paper examines said crises – 2007 cyberattacks on Estonian government, banks, and news media; the 2017 e-ID crisis; the ongoing COVID-19 pandemic; and the 2022 Russian invasion of Ukraine – and how governance decision-making following these crises has shaped the cybersecurity of the digital governance structure in Estonia. This paper employs a blended constructivist and historical institutionalist theoretical approach as a useful means to view governance and decision-making in the wake of cybersecurity incidents affecting the Estonian digital governance structure. Together, these theoretical groundings frame the topics of cybersecurity and digital governance in an Estonian context through a lens of ideation and experience, as well as institutional path dependencies over time and cybersecurity crises as critical junctures to study. Furthermore, this paper takes a qualitative approach, employing discourse analysis, policy analysis, and elite interviewing of Estonian officials involved in digital governance and cybersecurity in order to glean nuanced perspectives into the processes that followed these four crises. Ultimately, the results of this paper will offer insight into how governments undertake policy-driven change following cybersecurity crises to ensure sufficient security of their digitized service provisions. This paper’s findings are informative not only in continued decision-making in the Estonian system but also in other states currently implementing a digital governance structure, for which security mechanisms are of the utmost importance.Keywords: cybersecurity, digital governance, Estonia, crisis management, governance in crisis
Procedia PDF Downloads 1121780 Preparation of Papers - Developing a Leukemia Diagnostic System Based on Hybrid Deep Learning Architectures in Actual Clinical Environments
Authors: Skyler Kim
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An early diagnosis of leukemia has always been a challenge to doctors and hematologists. On a worldwide basis, it was reported that there were approximately 350,000 new cases in 2012, and diagnosing leukemia was time-consuming and inefficient because of an endemic shortage of flow cytometry equipment in current clinical practice. As the number of medical diagnosis tools increased and a large volume of high-quality data was produced, there was an urgent need for more advanced data analysis methods. One of these methods was the AI approach. This approach has become a major trend in recent years, and several research groups have been working on developing these diagnostic models. However, designing and implementing a leukemia diagnostic system in real clinical environments based on a deep learning approach with larger sets remains complex. Leukemia is a major hematological malignancy that results in mortality and morbidity throughout different ages. We decided to select acute lymphocytic leukemia to develop our diagnostic system since acute lymphocytic leukemia is the most common type of leukemia, accounting for 74% of all children diagnosed with leukemia. The results from this development work can be applied to all other types of leukemia. To develop our model, the Kaggle dataset was used, which consists of 15135 total images, 8491 of these are images of abnormal cells, and 5398 images are normal. In this paper, we design and implement a leukemia diagnostic system in a real clinical environment based on deep learning approaches with larger sets. The proposed diagnostic system has the function of detecting and classifying leukemia. Different from other AI approaches, we explore hybrid architectures to improve the current performance. First, we developed two independent convolutional neural network models: VGG19 and ResNet50. Then, using both VGG19 and ResNet50, we developed a hybrid deep learning architecture employing transfer learning techniques to extract features from each input image. In our approach, fusing the features from specific abstraction layers can be deemed as auxiliary features and lead to further improvement of the classification accuracy. In this approach, features extracted from the lower levels are combined into higher dimension feature maps to help improve the discriminative capability of intermediate features and also overcome the problem of network gradient vanishing or exploding. By comparing VGG19 and ResNet50 and the proposed hybrid model, we concluded that the hybrid model had a significant advantage in accuracy. The detailed results of each model’s performance and their pros and cons will be presented in the conference.Keywords: acute lymphoblastic leukemia, hybrid model, leukemia diagnostic system, machine learning
Procedia PDF Downloads 1871779 Lightweight Ceramics from Clay and Ground Corncobs
Authors: N.Quaranta, M. Caligaris, R. Varoli, A. Cristobal, M. Unsen, H. López
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Corncobs are agricultural wastes and they can be used as fuel or as raw material in different industrial processes like cement manufacture, contaminant adsorption, chemical compound synthesis, etc. The aim of this work is to characterize this waste and analyze the feasibility of its use as a pore-forming material in the manufacture of lightweight ceramics for the civil construction industry. The characterization of raw materials is carried out by using various techniques: electron diffraction analysis X-ray, differential and gravimetric thermal analyses, FTIR spectroscopy, ecotoxicity evaluation, among others. The ground corncobs, particle size less than 2 mm, are mixed with clay up to 30% in volume and shaped by uniaxial pressure of 25 MPa, with 6% humidity, in moulds of 70mm x 40mm x 18mm. Then the green bodies are heat treated at 950°C for two hours following the treatment curves used in ceramic industry. The ceramic probes are characterized by several techniques: density, porosity and water absorption, permanent volumetric variation, loss on ignition, microscopies analysis, and mechanical properties. DTA-TGA analysis of corncobs shows in the range 20°-250°C a small loss in TGA curve and exothermic peaks at 250°-500°C. FTIR spectrum of the corncobs sample shows the characteristic pattern of this kind of organic matter with stretching vibration bands of adsorbed water, methyl groups, C–O and C–C bonds, and the complex form of the cellulose and hemicellulose glycosidic bonds. The obtained ceramic bodies present external good characteristics without loose edges and adequate properties for the market requirements. The porosity values of the sintered pieces are higher than those of the reference sample without waste addition. The results generally indicate that it is possible to use corncobs as porosity former in ceramic bodies without modifying the usual sintering temperatures employed in the industry.Keywords: ceramic industry, biomass, recycling, hemicellulose glycosidic bonds
Procedia PDF Downloads 4051778 Crop Breeding for Low Input Farming Systems and Appropriate Breeding Strategies
Authors: Baye Berihun Getahun, Mulugeta Atnaf Tiruneh, Richard G. F. Visser
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Resource-poor farmers practice low-input farming systems, and yet, most breeding programs give less attention to this huge farming system, which serves as a source of food and income for several people in developing countries. The high-input conventional breeding system appears to have failed to adequately meet the needs and requirements of 'difficult' environments operating under this system. Moreover, the unavailability of resources for crop production is getting for their peaks, the environment is maltreated by excessive use of agrochemicals, crop productivity reaches its plateau stage, particularly in the developed nations, the world population is increasing, and food shortage sustained to persist for poor societies. In various parts of the world, genetic gain at the farmers' level remains low which could be associated with low adoption of crop varieties, which have been developed under high input systems. Farmers usually use their local varieties and apply minimum inputs as a risk-avoiding and cost-minimizing strategy. This evidence indicates that the conventional high-input plant breeding system has failed to feed the world population, and the world is moving further away from the United Nations' goals of ending hunger, food insecurity, and malnutrition. In this review, we discussed the rationality of focused breeding programs for low-input farming systems and, the technical aspect of crop breeding that accommodates future food needs and its significance for developing countries in the decreasing scenario of resources required for crop production. To this end, the application of exotic introgression techniques like polyploidization, pan-genomics, comparative genomics, and De novo domestication as a pre-breeding technique has been discussed in the review to exploit the untapped genetic diversity of the crop wild relatives (CWRs). Desired recombinants developed at the pre-breeding stage are exploited through appropriate breeding approaches such as evolutionary plant breeding (EPB), rhizosphere-related traits breeding, and participatory plant breeding approaches. Populations advanced through evolutionary breeding like composite cross populations (CCPs) and rhizosphere-associated traits breeding approach that provides opportunities for improving abiotic and biotic soil stress, nutrient acquisition capacity, and crop microbe interaction in improved varieties have been reviewed. Overall, we conclude that low input farming system is a huge farming system that requires distinctive breeding approaches, and the exotic pre-breeding introgression techniques and the appropriate breeding approaches which deploy the skills and knowledge of both breeders and farmers are vital to develop heterogeneous landrace populations, which are effective for farmers practicing low input farming across the world.Keywords: low input farming, evolutionary plant breeding, composite cross population, participatory plant breeding
Procedia PDF Downloads 521777 Sustainable Milling Process for Tensile Specimens
Authors: Shilpa Kumari, Ramakumar Jayachandran
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Machining of aluminium extrusion profiles in the automotive industry has gained much interest in the last decade, particularly due to the higher utilization of aluminum profiles and the weight reduction benefits it brings. Milling is the most common material removal process, where the rotary milling cutter is moved against a workpiece. The physical contact of the milling cutter to the workpiece increases the friction between them, thereby affecting the longevity of the milling tool and also the surface finish of the workpiece. To minimise this issue, the milling process uses cutting fluids or emulsions; however, the use of emulsion in the process has a negative impact on the environment ( such as consumption of water, oils and the used emulsion needs to be treated before disposal) and also on the personal ( may cause respiratory problems, exposure to microbial toxins generated by bacteria in the emulsions on prolonged use) working close to the process. Furthermore, the workpiece also needs to be cleaned after the milling process, which is not adding value to the process, and the cleaning also disperses mist of emulsion in the working environment. Hydro Extrusion is committed to improving the performance of sustainability from its operations, and with the negative impact of using emulsion in the milling process, a new innovative process- Dry Milling was developed to minimise the impact the cutting fluid brings. In this paper, the authors present one application of dry milling in the machining of tensile specimens in the laboratory. Dry milling is an innovative milling process without the use of any cooling/lubrication and has several advantages. Several million tensile tests are carried out in extrusion laboratories worldwide with the wet milling process. The machining of tensile specimens has a significant impact on the reliability of test results. The paper presents the results for different 6xxx alloys with different wall thicknesses of the specimens, which were machined by both dry and wet milling processes. For both different 6xxx alloys and different wall thicknesses, mechanical properties were similar for samples milled using dry and wet milling. Several tensile specimens were prepared using both dry and wet milling to compare the results, and the outcome showed the dry milling process does not affect the reliability of tensile test results.Keywords: dry milling, tensile testing, wet milling, 6xxx alloy
Procedia PDF Downloads 1981776 A Study on the Influence of Salicylic Acid on Sub-Mergence Stress Recovery of Selected Rice Cultivars Grown in Kebbi State Northwest Nigeria
Authors: Ja'afar Umar, Salisu Naziru
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Submergence stress in plants refers to the physiological and biochemical challenges that occur when plants are partially or fully submerged in water. This type of stress primarily affects plants in flood-prone areas or regions with heavy rainfall, where oxygen availability and other essential resources are limited. Salicylic acid (SA) is an important plant hormone involved in various physiological processes and responses to environmental stress, particularly in plant defense mechanisms against pathogens. Its role as a signaling molecule in plants is crucial for activating defense pathways, regulating growth, and managing responses to biotic (living) and abiotic (non-living) stresses. The study involved using salicylic acid (SA) at concentrations of 1g/L, 2g/L, and 3g/L, dissolved in water, to treat rice plants during submergence stress. The experiment had four treatments: 0g/L (control), 1g/L, 2g/L, and 3g/L of SA, each with four replications. Rice seedlings were submerged in water for 11 days and then desubmerged for 7 days. During the experiment, all plants except the control received a foliar spray of SA solutions, while control plants were sprayed with distilled water. The results indicate a significant difference (P<0.05) between the control and salicylic acid (SA)-treated rice plants. SalicyJalic acid, particularly at concentrations of 1g/L, 2g/L, and 3g/L, generally improved the recovery of all four rice cultivars from submergence stress, as reflected by increased numbers of nodes, longer internodes, taller plants, and longer root lengths compared to untreated controls. Salicylic acid, particularly at concentrations of 1g/L, 2g/L, and 3g/L, generally improved the recovery of all four rice cultivars from submergence stress, as reflected by increased numbers of nodes, longer internodes, taller plants, and longer root lengths compared to untreated controls.Keywords: submergence, stress, rice, salicylic
Procedia PDF Downloads 181775 The Multiple Sclerosis condition and the Role of Varicella-zoster virus in its Progression
Authors: Sina Mahdavi, Mahdi Asghari Ozma
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Multiple sclerosis (MS) is the most common inflammatory autoimmune disease of the CNS that affects the myelination process in the central nervous system (CNS). Complex interactions of various "environmental or infectious" factors may act as triggers in autoimmunity and disease progression. The association between viral infections, especially human Varicella-zoster virus (VZV) and MS is one potential cause that is not well understood. This study aims to summarize the available data on VZV retrovirus infection in MS disease progression. For this study, the keywords "Multiple sclerosis", " Human Varicella-zoster virus ", and "central nervous system" in the databases PubMed, Google Scholar, Sid, and MagIran between 2016 and 2022 were searched and 14 articles were chosen, studied, and analyzed. Analysis of the amino acid sequences of HNRNPA1 with VZV proteins has shown a 62% amino acid sequence similarity between VZV gE and the PrLD/M9 epitope region (TNPO1 binding domain) of mutant HNRNPA1. A heterogeneous nuclear ribonucleoprotein (hnRNP), which is produced by HNRNPA1, is involved in the processing and transfer of mRNA and pre-mRNA. Mutant HNRNPA1 mimics gE of VZV as an antigen that leads to autoantibody production. Mutant HnRNPA1 translocates to the cytoplasm, after aggregation is presented by MHC class I, followed by CD8 + cells. Of these, antibodies and immune cells against the gE epitopes of VZV remain due to the memory immune response, causing neurodegeneration and the development of MS in genetically predisposed individuals. VZV expression during the course of MS is present in genetically predisposed individuals with HNRNPA1 mutation, suggesting a link between VZV and MS, and that this virus may play a role in the development of MS by inducing an inflammatory state. Therefore, measures to modulate VZV expression may be effective in reducing inflammatory processes in demyelinated areas of MS patients in genetically predisposed individuals.Keywords: multiple sclerosis, varicella-zoster virus, central nervous system, autoimmunity
Procedia PDF Downloads 761774 Beyond Sexual Objectification: Moderation Analysis of Trauma and Overexcitability Dynamics in Women
Authors: Ritika Chaturvedi
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Introduction: Sexual objectification, characterized by the reduction of an individual to a mere object of sexual desire, remains a pervasive societal issue with profound repercussions on individual well-being. Such experiences, often rooted in systemic and cultural norms, have long-lasting implications for mental and emotional health. This study aims to explore the intricate relationship between experiences of sexual objectification and insidious trauma, further investigating the potential moderating effects of overexcitability as proposed by Dabrowski's theory of positive disintegration. Methodology: The research involved a comprehensive cohort of 204 women, spanning ages from 18 to 65 years. Participants were tasked with completing self-administered questionnaires designed to capture their experiences with sexual objectification. Additionally, the questionnaire assessed symptoms indicative of insidious trauma and explored overexcitability across five distinct domains: emotional, intellectual, psychomotor, sensory, and imaginational. Employing advanced statistical techniques, including multiple regression and moderation analysis, the study sought to decipher the intricate interplay among these variables. Findings: The study's results revealed a compelling positive correlation between experiences of sexual objectification and the onset of symptoms indicative of insidious trauma. This correlation underscores the profound and detrimental effects of sexual objectification on an individual's psychological well-being. Interestingly, the moderation analyses introduced a nuanced understanding, highlighting the differential roles of various overexcitability. Specifically, emotional, intellectual, and sensual overexcitability were found to exacerbate trauma symptomatology. In contrast, psychomotor overexcitability emerged as a protective factor, demonstrating a mitigating influence on the relationship between sexual objectification and trauma. Implications: The study's findings hold significant implications for a diverse array of stakeholders, encompassing mental health practitioners, educators, policymakers, and advocacy groups. The identified moderating effects of overexcitability emphasize the need for tailored interventions that consider individual differences in coping and resilience mechanisms. By recognizing the pivotal role of overexcitability in modulating the traumatic consequences of sexual objectification, this research advocates for the development of more nuanced and targeted support frameworks. Moreover, the study underscores the importance of continued research endeavors to unravel the intricate mechanisms and dynamics underpinning these relationships. Such endeavors are crucial for fostering the evolution of informed, evidence-based interventions and strategies aimed at mitigating the adverse effects of sexual objectification and promoting holistic well-being.Keywords: sexual objectification, insidious trauma, emotional overexcitability, intellectual overexcitability, sensual overexcitability, psychomotor overexcitability, imaginational overexcitability
Procedia PDF Downloads 531773 A Ku/K Band Power Amplifier for Wireless Communication and Radar Systems
Authors: Meng-Jie Hsiao, Cam Nguyen
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Wide-band devices in Ku band (12-18 GHz) and K band (18-27 GHz) have received significant attention for high-data-rate communications and high-resolution sensing. Especially, devices operating around 24 GHz is attractive due to the 24-GHz unlicensed applications. One of the most important components in RF systems is power amplifier (PA). Various PAs have been developed in the Ku and K bands on GaAs, InP, and silicon (Si) processes. Although the PAs using GaAs or InP process could have better power handling and efficiency than those realized on Si, it is very hard to integrate the entire system on the same substrate for GaAs or InP. Si, on the other hand, facilitates single-chip systems. Hence, good PAs on Si substrate are desirable. Especially, Si-based PA having good linearity is necessary for next generation communication protocols implemented on Si. We report a 16.5 to 25.5 GHz Si-based PA having flat saturated power of 19.5 ± 1.5 dBm, output 1-dB power compression (OP1dB) of 16.5 ± 1.5 dBm, and 15-23 % power added efficiency (PAE). The PA consists of a drive amplifier, two main amplifiers, and lump-element Wilkinson power divider and combiner designed and fabricated in TowerJazz 0.18µm SiGe BiCMOS process having unity power gain frequency (fMAX) of more than 250 GHz. The PA is realized as a cascode amplifier implementing both heterojunction bipolar transistor (HBT) and n-channel metal–oxide–semiconductor field-effect transistor (NMOS) devices for gain, frequency response, and linearity consideration. Particularly, a body-floating technique is utilized for the NMOS devices to improve the voltage swing and eliminate parasitic capacitances. The developed PA has measured flat gain of 20 ± 1.5 dB across 16.5-25.5 GHz. At 24 GHz, the saturated power, OP1dB, and maximum PAE are 20.8 dBm, 18.1 dBm, and 23%, respectively. Its high performance makes it attractive for use in Ku/K-band, especially 24 GHz, communication and radar systems. This paper was made possible by NPRP grant # 6-241-2-102 from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors.Keywords: power amplifiers, amplifiers, communication systems, radar systems
Procedia PDF Downloads 1111772 Membrane Bioreactor for Wastewater Treatment and Reuse
Authors: Sarra Kitanou
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Water recycling and reuse is an effective measure to solve the water stress problem. The sustainable use of water resource has become a national development strategy in Morocco. A key aspect of improving overall sustainability is the potential for direct wastewater effluent reuse. However, the hybrid technology membrane bioreactors (MBR) have been identified as an attractive option for producing high quality and nutrient-rich effluents for wastewater treatment. It is based on complex interactions between biological processes, filtration process and rheological properties of the liquid to be treated. Currently, with the evolution of wastewater treatment projects in Morocco, the MBR technology can be used as a technology treating different types of wastewaters and to produce effluent with suitable quality for reuse. However, the energetic consumption of this process is a great concern, which can limit the development and implementation of this technology. In this investigation, the electric energy consumption of an ultrafiltration membrane bioreactor process in domestic wastewater treatment is evaluated and compared to some MBR installations based on literature review. Energy requirements of the MBR are linked to operational parameters and reactor performance. The analysis of energy consumption shows that the biological aeration and membrane filtration are more energy consuming than the other components listed as feed and recirculation pumps. Biological aeration needs 53% of the overall energetic consumption and the specific energy consumption for membrane filtration is about 25%. However, aeration is a major energy consumer, often exceeding 50% share of total energy consumption. The optimal results obtained on the MBR process (pressure p = 1.15 bar), hydraulic retention time (15 h) showed removal efficiencies up to 90% in terms of organic compounds removal, 100% in terms of suspended solids presence and up to 80% reduction of total nitrogen and total phosphorus. The effluent from this MBR system could be considered as qualified for irrigation reuse, showing its potential application in the future.Keywords: hybrid process, membrane bioreactor, wastewater treatment, reuse
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