Search results for: modern hair loass treatments
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4698

Search results for: modern hair loass treatments

3588 Improving the Management Systems of the Ownership Risks in Conditions of Transformation of the Russian Economy

Authors: Mikhail V. Khachaturyan

Abstract:

The article analyzes problems of improving the management systems of the ownership risks in the conditions of the transformation of the Russian economy. Among the main sources of threats business owners should highlight is the inefficiency of the implementation of business models and interaction with hired managers. In this context, it is particularly important to analyze the relationship of business models and ownership risks. The analysis of this problem appears to be relevant for a number of reasons: Firstly, the increased risk appetite of the owner directly affects the business model and the composition of his holdings; secondly, owners with significant stakes in the company are factors in the formation of particular types of risks for owners, for which relations have a significant influence on a firm's competitiveness and ultimately determines its survival; and thirdly, inefficient system of management ownership of risk is one of the main causes of mass bankruptcies, which significantly affects the stable operation of the economy as a whole. The separation of the processes of possession, disposal and use in modern organizations is the cause of not only problems in the process of interaction between the owner and managers in managing the organization as a whole, but also the asymmetric information about the kinds and forms of the main risks. Managers tend to avoid risky projects, inhibit the diversification of the organization's assets, while owners can insist on the development of such projects, with the aim not only of creating new values for themselves and consumers, but also increasing the value of the company as a result of increasing capital. In terms of separating ownership and management, evaluation of projects by the ratio of risk-yield requires preservation of the influence of the owner on the process of development and making management decisions. It is obvious that without a clearly structured system of participation of the owner in managing the risks of their business, further development is hopeless. In modern conditions of forming a risk management system, owners are compelled to compromise between the desire to increase the organization's ability to produce new value, and, consequently, increase its cost due to the implementation of risky projects and the need to tolerate the cost of lost opportunities of risk diversification. Improving the effectiveness of the management of ownership risks may also contribute to the revitalization of creditors on implementation claims to inefficient owners, which ultimately will contribute to the efficiency models of ownership control to exclude variants of insolvency. It is obvious that in modern conditions, the success of the model of the ownership of risk management and audit is largely determined by the ability and willingness of the owner to find a compromise between potential opportunities for expanding the firm's ability to create new value through risk and maintaining the current level of new value creation and an acceptable level of risk through the use of models of diversification.

Keywords: improving, ownership risks, problem, Russia

Procedia PDF Downloads 349
3587 Scope of Lasers in Periodontics

Authors: Atmaja Patel

Abstract:

Since the development of lasers in 1951, the first medical application was reported by Goldman in 1962. In 1960, T.H. Maiman produced the first Ruby laser and was used in cardiovascular surgery by McGuff in 1963. After a long time of investigations and new developments in laser technology first clinical applications were performed by Choy and Ginsburg in 1983. Introduction of the first true dental laser was in 1989. This paper is to highlight the various treatments and prevention of periodontal diseases. Lasers have become more predictable and effective form of treatment for periodontal diseases. The advantages of lasers include reduced use of anaesthesia, coagulation that yields a dry surgical field and hence better visibility, reduced need of sutures, minimal swelling and scarring, less pain and medication, faster healing and increased patient acceptance.

Keywords: lasers, periodontal surgery, diode laser, healing

Procedia PDF Downloads 319
3586 Contact Phenomena in Medieval Business Texts

Authors: Carmela Perta

Abstract:

Among the studies flourished in the field of historical sociolinguistics, mainly in the strand devoted to English history, during its Medieval and early modern phases, multilingual texts had been analysed using theories and models coming from contact linguistics, thus applying synchronic models and approaches to the past. This is true also in the case of contact phenomena which would transcend the writing level involving the language systems implicated in contact processes to the point of perceiving a new variety. This is the case for medieval administrative-commercial texts in which, according to some Scholars, the degree of fusion of Anglo-Norman, Latin and middle English is so high a mixed code emerges, and there are recurrent patterns of mixed forms. Interesting is a collection of multilingual business writings by John Balmayn, an Englishman overseeing a large shipment in Tuscany, namely the Cantelowe accounts. These documents display various analogies with multilingual texts written in England in the same period; in fact, the writer seems to make use of the above-mentioned patterns, with Middle English, Latin, Anglo-Norman, and the newly added Italian. Applying an atomistic yet dynamic approach to the study of contact phenomena, we will investigate these documents, trying to explore the nature of the switching forms they contain from an intra-writer variation perspective. After analysing the accounts and the type of multilingualism in them, we will take stock of the assumed mixed code nature, comparing the characteristics found in this genre with modern assumptions. The aim is to evaluate the possibility to consider the switching forms as core elements of a mixed code, used as professional variety among merchant communities, or whether such texts should be analysed from a switching perspective.

Keywords: historical sociolinguistics, historical code switching, letters, medieval england

Procedia PDF Downloads 75
3585 Intercultural Education and Changing Paradigms of Education: A Research Survey

Authors: Shalini Misra

Abstract:

The means and methods of education have been changing fast since the invention of internet. Both, ancient and modern education emphasized on the holistic development of students. But, a significant change has been observed in the 21st century learners. Online classes, intercultural and interdisciplinary education which were exceptions in the past, are setting new trends in the field of education. In the modern era, intercultural and interpersonal skills are of immense importance, not only for students but for everyone. It sets a platform for better understanding and deeper learning by ensuring the active participation and involvement of students belonging to different social and cultural backgrounds in various academic and non-academic pursuits. On October 31, 2015, on the occasion of 140th birth anniversary of Sardar Vallabhbhai Patel, Hon’ble Prime Minister of India, Narendra Modi announced a wonderful initiative, ‘Ek Bharat Shreshtha Bharat’ i.e. ‘One India Best India’ commonly known as ‘EBSB’. The program highlighted India’s rich culture and traditions. The objective of the program was to foster a better understanding and healthy relationship among Indian States. Under this program, a variety of subjects were covered like ‘Arts, Culture and Language’ .It was claimed to be a successful cultural exchange where students from diverse communities shared their thoughts and experiences with one another. Under this online cultural exchange program, the state of Uttarakhand was paired with the state of Karnataka in the year 2022. The present paper proposes to undertake a survey of a total of thirty secondary level students of Uttarakhand and the partner state Karnataka, who participated in this program with a purpose of learning and embracing new ideas and culture thus promoting intercultural education. It aims to study and examine the role of intercultural education in shifting and establishing new paradigms of education.

Keywords: education, intercultural, interpersonal, traditions, understanding

Procedia PDF Downloads 79
3584 Non-Invasive Techniques of Analysis of Painting in Forensic Fields

Authors: Radka Sefcu, Vaclava Antuskova, Ivana Turkova

Abstract:

A growing market with modern artworks of a high price leads to the creation and selling of artwork counterfeits. Material analysis is an important part of the process of assessment of authenticity. Knowledge of materials and techniques used by original authors is also necessary. The contribution presents possibilities of non-invasive methods of structural analysis in research on paintings. It was proved that unambiguous identification of many art materials is feasible without sampling. The combination of Raman spectroscopy with FTIR-external reflection enabled the identification of pigments and binders on selected artworks of prominent Czech painters from the first half of the 20th century – Josef Čapek, Emil Filla, Václav Špála and Jan Zrzavý. Raman spectroscopy confirmed the presence of a wide range of white pigments - lead white, zinc white, titanium white, barium white and also Freeman's white as a special white pigment of painting. Good results were obtained for red, blue and most of the yellow areas. Identification of green pigments was often impossible due to strong fluorescence. Oil was confirmed as a binding medium on most of the analyzed artworks via FTIR - external reflection. Collected data present the valuable background for the determination of art materials characteristic for each painter (his palette) and its development over time. Obtained results will further serve as comparative material for the authentication of artworks. This work has been financially supported by the project of the Ministry of the Interior of the Czech Republic: The Development of a Strategic Cluster for Effective Instrumental Technological Methods of Forensic Authentication of Modern Artworks (VJ01010004).

Keywords: non-invasive analysis, Raman spectroscopy, FTIR-external reflection, forgeries

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3583 Socio-Cultural Representations through Lived Religions in Dalrymple’s Nine Lives

Authors: Suman

Abstract:

In the continuous interaction between the past and the present that historiography is, each time when history gets re/written, a new representation emerges. This new representation is a reflection of the earlier archives and their interpretations, fragmented remembrances of the past, as well as the reactions to the present. Memory, or lack thereof, and stereotyping generally play a major role in this representation. William Dalrymple’s Nine Lives: In Search of the Sacred in Modern India (2009) is one such written account that sets out to narrate the representations of religion and culture of India and contemporary reactions to it. Dalrymple’s nine saints belong to different castes, sects, religions, and regions. By dealing with their religions and expressions of those religions, and through the lived mysticism of these nine individuals, the book engages with some important issues like class, caste and gender in the contexts provided by historical as well as present India. The paper studies the development of religion and accompanied feeling of religiosity in modern as well as historical contexts through a study of these elements in the book. Since, the language used in creation of texts and the literary texts thus produced create a new reality that questions the stereotypes of the past, and in turn often end up creating new stereotypes or stereotypical representations at times, the paper seeks to actively engage with the text in order to identify and study such stereotypes, along with their changing representations. Through a detailed examination of the book, the paper seeks to unravel whether some socio-cultural stereotypes existed earlier, and whether there is development of new stereotypes from Dalrymple’s point of view as an outsider writing on issues that are deeply rooted in the cultural milieu of the country. For this analysis, the paper takes help from the psycho-literary theories of stereotyping and representation.

Keywords: stereotyping, representation, William Dalrymple, religion

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3582 Understanding and Explaining Urban Resilience and Vulnerability: A Framework for Analyzing the Complex Adaptive Nature of Cities

Authors: Richard Wolfel, Amy Richmond

Abstract:

Urban resilience and vulnerability are critical concepts in the modern city due to the increased sociocultural, political, economic, demographic, and environmental stressors that influence current urban dynamics. Urban scholars need help explaining urban resilience and vulnerability. First, cities are dominated by people, which is challenging to model, both from an explanatory and a predictive perspective. Second, urban regions are highly recursive in nature, meaning they not only influence human action, but the structures of cities are constantly changing due to human actions. As a result, explanatory frameworks must continuously evolve as humans influence and are influenced by the urban environment in which they operate. Finally, modern cities have populations, sociocultural characteristics, economic flows, and environmental impacts on order of magnitude well beyond the cities of the past. As a result, the frameworks that seek to explain the various functions of a city that influence urban resilience and vulnerability must address the complex adaptive nature of cities and the interaction of many distinct factors that influence resilience and vulnerability in the city. This project develops a taxonomy and framework for organizing and explaining urban vulnerability. The framework is built on a well-established political development model that includes six critical classes of urban dynamics: political presence, political legitimacy, political participation, identity, production, and allocation. In addition, the framework explores how environmental security and technology influence and are influenced by the six elements of political development. The framework aims to identify key tipping points in society that act as influential agents of urban vulnerability in a region. This will help analysts and scholars predict and explain the influence of both physical and human geographical stressors in a dense urban area.

Keywords: urban resilience, vulnerability, sociocultural stressors, political stressors

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3581 Family Models in Contemporary Multicultural Society: Exploratory Study Applied to Immigrants of Second and Third Generations

Authors: Danièle Peto

Abstract:

A qualitative research based on twenty-eight semi-structured interviews of students in Social Work, in Brussels (Belgium), showed specific results for the Arab and Muslim students: second and third generations immigrants build their identity on the basis of a mix of differentiation with and recognition of their parents' culture of origin. Building a bridge between Modernity and Tradition, they claim active citizenship; at the same time they show and live by values and religious believes which reinforce the link to their parents’ origins. But they present those values and believes as their own rational choices among other choices, all available and rich for our multicultural society. The way they speak of themselves is highly modern. But, they still have to build a third way to find a place for themselves in society: one allowing them to live their religion as a partially public matter (when the Occidental society leaves no such place for religion) while ensuring, at the same time, the development of independent critical thought. On this basis, other semi-structured interviews are being laid with Social workers working with families from diverse ethnic backgrounds. They will verify the reality of those identity and cultural bricolages when those young adults of second and third generations build their own family. In between the theoretical models of traditional family and modern family, shall we find a new model, hybrid and more or less stable, combining some aspects of the former and the latter? The exploratory research phase focuses on three aspects of building a family life in this context : the way those generations play, discursively or not, in between their parents and the society in which they grew up; the importance of intercultural dialogue in this process of building; and testing the hypothesis that some families, in our society, show a special way of courting Modernity.

Keywords: family models, identity bricolages, intercultural, modernity and tradition

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3580 Efficiency of Nutritional Support Treatments in Children With Failure to Thrive

Authors: Mehves Isiklar Ekici, Ceyda Tuna Kirsaclioglu, Zarife Kuloglu, Aydan Kansu

Abstract:

Malnutrition is an important cause of morbidity and mortality as it accounts for 45% of child deaths under the age of 5 worldwide. Therefore, early recognition and effective treatment of failure to thrive and malnutrition are important. In this study, it was aimed to retrospectively evaluate the nutritional support treatment approaches (nutrition education and diet enrichment / use of enteral nutrition products) applied in children followed up with growth failure without underlying organic causes, and to compare the efficacy of nutritional support treatments. In this study, children aged 1 month to 18 years diagnosed with growth failure who were followed up for at least 12 months between January 2011 and February 2020, were included. Anthropometric measurements at baseline and during follow-up, type of nutritional support therapy and treatment compliance were evaluated based on the retrospective records. 119 children (median age:3.2, 69 girls) were included in the study. Nutrition education and dietary enrichment were provided to 28% of the patients (Group 1). In addition to dietary education and recommendations, enteral nutrition supplements was given in 78% of them (Group 2). Compliance to the treatment rates of the patients in Group 1 and Group 2 were not significantly different at both 6th and 12th month controls. At the end of the follow up children who comply with the treatment in Group 1 had significant increase in weight for age z scores (-1.74 vs 0.05, respectively, p=0.019) and body mass index z scores (-1.47 vs -0.53, respectively, p=0.034) compared with baseline measurements. Similar to Group 1, in Group 2 children with treatment compliance, had a significant increase in weight for age z scores (-2.24 vs. -0.54, respectively, p=0.00) and body mass index z scores (-2.27 vs. -1.06, respectively, p=0.00) compared with baseline measurements. The rate of patients with severe malnutrition decreased from 15% to 12%, for moderate malnutrition decreased from 54% to 33%. Moreover, it was observed that this decrease in the rate of patients with both severe and moderate malnutrition was more prominent in patients under 3 years of age. Although there was a significant increase in anthropometric measurements with treatment in both groups, there was no significant difference in between two groups terms of change in anthropometric measurements (p>0.05), therefore effectiveness. Failure to thrive and malnutrition in infancy and childhood cause health problems that can affect adult life. To conclude, nutritional education - dietary enrichment. recommendations and use of enteral nutrition supplements were both proven beneficial in this study. Researchers are willing to underline that the most important part of the treatment is to include the family to the process to ensure the treatment compliance.

Keywords: enteral nutrition supplements, failure to thrive, malnutrition, nutritional education

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3579 Probiotics in Anxiety and Depression

Authors: Pilar Giffenig, Avanna Kotlarz, Taylor Dehring

Abstract:

Anxiety and depression are common mental illnesses in the U.S today. While there are various treatments for these mental health disorders, many of the medications come with a large variety of side effects that decrease medication compliance. Recent studies have looked at the impact of probiotics on anxiety and depression. Our goal was to determine whether probiotics could help relieve symptoms of anxiety and or depression. We conducted a literature search of three databases focusing on systematic reviews and RTC and found 25 articles, 8 of which were used for our analysis. Seven out of the eight articles showed that probiotics have the potential to significantly reduce symptoms of anxiety and depression. However, larger study sample sizes, type of probiotic, and correct dosage are required in future research to determine the role of probiotics in the treatment of anxiety and depression.

Keywords: probiotics, anxiety, depression, treatment, psychology, nutrition

Procedia PDF Downloads 270
3578 Efficient Chiller Plant Control Using Modern Reinforcement Learning

Authors: Jingwei Du

Abstract:

The need of optimizing air conditioning systems for existing buildings calls for control methods designed with energy-efficiency as a primary goal. The majority of current control methods boil down to two categories: empirical and model-based. To be effective, the former heavily relies on engineering expertise and the latter requires extensive historical data. Reinforcement Learning (RL), on the other hand, is a model-free approach that explores the environment to obtain an optimal control strategy often referred to as “policy”. This research adopts Proximal Policy Optimization (PPO) to improve chiller plant control, and enable the RL agent to collaborate with experienced engineers. It exploits the fact that while the industry lacks historical data, abundant operational data is available and allows the agent to learn and evolve safely under human supervision. Thanks to the development of language models, renewed interest in RL has led to modern, online, policy-based RL algorithms such as the PPO. This research took inspiration from “alignment”, a process that utilizes human feedback to finetune the pretrained model in case of unsafe content. The methodology can be summarized into three steps. First, an initial policy model is generated based on minimal prior knowledge. Next, the prepared PPO agent is deployed so feedback from both critic model and human experts can be collected for future finetuning. Finally, the agent learns and adapts itself to the specific chiller plant, updates the policy model and is ready for the next iteration. Besides the proposed approach, this study also used traditional RL methods to optimize the same simulated chiller plants for comparison, and it turns out that the proposed method is safe and effective at the same time and needs less to no historical data to start up.

Keywords: chiller plant, control methods, energy efficiency, proximal policy optimization, reinforcement learning

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3577 Investigation of the Prevalence, Phenotypes, and Risk Factors Associated with Demodex Infestation and Its Relationship with Acne

Authors: Sina Alimohammadi, Mahnaz Banihashemi, Maryam Poursharif

Abstract:

Demodex is a mandatory parasite of pilosebaceous. D. folliculorum lives as a single parasite or as a number of parasites in hair follicles, and D. brevis as a single parasite living in sebaceous glands. Transmission of Demodex from one person to another requires direct skin contact; it also has a greater density in the forehead, cheeks, nose, and nasolabial folds. Demodex can cause some clinical symptoms such as follicular pityriasis, rosacea-like demodicosis, postural folliculitis, papules, seborrheic dermatitis, blepharitis, dermatitis around the lips, and hyperpigmented spots. In this study, the prevalence of Demodex species in patients referred to the dermatology department of Sayad Shirazi Hospital Gorgan, Iran, in the years 2019-2020 was investigated. Material and Methods: The study population consisted of 242 samples taken from the people referred to the dermatology department of Sayad Shirazi Hospital during the years 2019-2020, which were sampled by adhesive tape. All of the participants completed the questionnaires. The samples were examined microscopically for the presence of Demodex. Results: Out of 242 participants, 67 (27.68%) were infected with Demodex. Most cases of infection were observed in the group of 21 to 30 years (28 people; 11.57%) and then in the group of 31 to 40 years (21 people; 8.67%). Also, in the group of people under 10 years and over 60 years, no positive cases (0%) of Demodex were observed in microscopic examinations. Out of 11 variables, there was a statistically significant difference in relation to the three variables of age (P = 0.000003), use of cleansing solutions (P = 0.002), and the presence of acne (P = 0.0013). Conclusion: According to the results of this study, it was found that the incidence of Demodex in one group of acne patients is higher than in others, which emphasizes the possible role of Demodex in the pathogenesis of acne. In this study, there was an inverse relationship between the incidence of Demodex and the use of skin cleansing solutions. Also, the prevalence of Demodex is higher in the group of 20-30 years, and its prevalence does not increase with age. Due to the possibility of drug resistance in the future, regular studies on genotyping and drug resistance are recommended.

Keywords: acne, demodex, mite, prevalence

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3576 Symbolic Status of Architectural Identity: Example of Famagusta Walled City

Authors: Rafooneh Mokhtarshahi Sani

Abstract:

This study explores how the residents of a conserved urban area have used goods and ideas as resources to maintain an enviable architectural identity. Whereas conserved urban quarters are seen as role model for maintaining architectural identity, the article describes how their residents try to give a contemporary modern image to their homes. It is argued that despite the efforts of authorities and decision makers to keep and preserve the traditional architectural identity in conserved urban areas, people have already moved on and have adjusted their homes with their preferred architectural taste. Being through such conflict of interests, have put the future of architectural identity in such places at risk. The thesis is that, on the one hand, such struggle over a desirable symbolic status in identity formation is taking place, and, on the other, it is continuously widening the gap between the real and ideal identity in the built environment. The study then analytically connects the concept of symbolic status to current identity debates. As an empirical research, this study uses systematic social and physical observation methods to describe and categorize the characteristics of settlements in Walled City of Famagusta, which symbolically represent the modern houses. The Walled City is a cultural heritage site, which most of its urban context has been conserved. Traditional houses in this area demonstrate the identity of North Cyprus architecture. The conserved residential buildings, however, either has been abandoned or went through changes by their users to present the ideal image of contemporary life. In the concluding section, the article discusses the differences between the symbolic status of people and authorities in defining a culturally valuable contemporary home. And raises the question of whether we can talk at all about architectural identity in terms of conserving the traditional style, and how we may do so on the basis of dynamic nature of identity and the necessity of its acceptance by the users.

Keywords: symbolic status, architectural identity, conservation, facades, Famagusta walled city

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3575 High Performance Ceramic-Based Phthalonitrile Micro and Nanocomposites

Authors: M. Derradji, W. B. Liu

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The current work discusses the effects of adding various types of ceramic fillers on the curing behavior, thermal, mechanical, anticorrosion, and UV shielding properties of the bisphenol-A based phthalonitrile resins. The effects of different ceramic filler contents and sizes as well as their surface treatments are also discussed in terms of their impact on the morphology and mechanisms of enhancement. The synergistic effect obtained by these combinations extends the use of the phthalonitrile resins to more exigent applications such as aerospace and military. The presented results reveal the significant advantages that can be obtained from the preparation of hybrid materials based on phthalonitrile resins and open the way for further research in the field.

Keywords: mechanical properties, particle reinforced composites, polymer matrix composites (PMCs), thermal properties

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3574 Potential of Ozonation and Phytoremediation to Reduce Hydrocarbon Levels Remaining after the Pilot Scale Microbial Based Bioremediation (Land-Farming) of a Heavily Polluted Soil

Authors: Hakima Althalb

Abstract:

Petroleum contamination of sandy soils is a severe environmental problem in Libya, but relatively little work has been carried out to optimize the bioremediation of such heavily contaminated soil, particularly at a pilot scale. The purpose of this research was to determine the potential for the microbial-based bioremediation of hydrocarbon-contaminated soil obtained from an oil refinery in Libya and to assess the potential of both ozonation and phytoremediation (both applied after initial bioremediation) to reduce residual hydrocarbon levels. Plots containing 500 kg soil (triplicates) (contaminated soil diluted with clean soil 50% volume) were set up, (designated as Land Treatment Units; LTUs) containing five different nutrient levels and mixtures (Urea + NPK (nitrogen; phosphor; potassium) mixtures) to obtain C:N:P ratios 100:10:1, and monitored for 90 days. Hydrocarbon levels, microbial numbers, and toxicity (EC50 using luminescent microbial based tests) were assessed. Hydrocarbon levels in non-diluted and diluted soil ranged from 20 733-22 366 mg/kg and from 16 000-17 000 mg/kg respectively. Although all the land treatment units revealed a significant hydrocarbon reduction over time, the highest reduction in hydrocarbon levels obtained was around 60%. For example, 63% hydrocarbon removal was observed using a mixture of urea and NPK with a C:N:P ratio of 100:10:1). Soil toxicity (as assessed using luminescence based toxicity assays) reduced in line with the reduction in total petroleum hydrocarbons observed. However, as relatively high residual TPH (total petroleum hydrocarbon) levels (ranging from 6033-14166mg/kg) were still present after initial bioremediation two ‘post-treatments’ (phytoremediation and ozonation) were attempted to remove residual hydrocarbons remaining. Five locally grown (agriculturally important) plant species were tested. The germination of all plants examined was strongly inhibited (80-100%) and seedlings failed to grow well in the contaminated soil, indicating that the previously bioremediated soils were still toxic to the plants. Subsequent ozonation followed by another bioremediation of soil was more successful than phytoremediation. But even the most promising successful treatment in this study (ozonation for 6 hours at 25ppm followed by bioremediation) still only removed approximately 31% of the residual hydrocarbons. Overall, this work showed that the bioremediation of such highly contaminated soils is difficult and that a combination of treatments would be required to achieve successful remediation. Even after initial dilution and bioremediation the soils remained toxic to plant growth and were therefore not suitable for phytoremediation.

Keywords: bioremediation, petroleum hydrocarbons, ozone, phytoremediation

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3573 The Destruction of Memory: Ataturk Cultural Centre

Authors: Birge Yildirim Okta

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This paper aims to narrate the story of Atatürk Cultural Center in Taksim Square, which was demolished in 2018, and discuss its architectonic as a social place of memory and its existence and demolishment as the space of politics. Focusing on the timeline starting from early republican period till today, the paper uses narrative discourse analysis to research Atatürk Cultural Center as a place of memory and a space of politics in its existence. After the establishment of Turkish Republic, one of most important implementation in Taksim Square, reflecting the internationalist style, was the construction of Opera Building in Prost Plan. The first design of the opera building belonged to Aguste Perret, which could not be implemented due to economic hardship during World War II. Later the project was designed by architects Feridun Kip and Rüknettin Güney in 1946 but could not be completed due to 1960 military coup. Later the project was shifted to another architect Hayati Tabanlıoglu, with a change in its function as a cultural center. Eventually, the construction of the building was completed in 1969 in a completely different design. AKM became a symbol of republican modernism not only with its modern architectural style but also with it is function as the first opera building of the republic, reflecting the western, modern cultural heritage by professional groups, artists and the intelligentsia. In 2005, Istanbul’s council for the protection of cultural heritage decided to list AKM as a grade 1 cultural heritage, ending a period of controversy which saw calls for the demolition of the center as it was claimed it ended its useful lifespan. In 2008 the building was announced to be closed for repairs and restoration. Over the following years, the building was demolished piece by piece silently while Taksim mosque has been built just in front of Atatürk Cultural Center. Belonging to the early republican period, AKM was a representation of a cultural production of a modern society for the emergence and westward looking, secular public space in Turkey. Its erasure from Taksim scene under the rule of the conservative government, Justice and Development Party and the construction of Taksim mosque in front of AKM’s parcel is also representational. The question of governing the city through space has always been an important aspect for governments, those holding political power since cities are the chaotic environments that are seen as a threat for the governments, carrying the tensions of proletariat or the contradictory groups. The story of AKM as a dispositive or a regulatory apparatus demonstrates how space itself is becoming a political medium, to transform the socio-political condition. The article aims to discuss the existence and demolishment of Atatürk Cultural Center by discussing the constructed and demolished building as a place of memory and a space of politics.

Keywords: space of politics, place of memory, atatürk cultural center, taksim square

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3572 Repurposing Dairy Manure Solids as a Non- Polluting Fertilizer and the Effects on Nutrient Recovery in Tomatoes (Solanum Lycopersicum)

Authors: Devon Simpson

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Recycled Manure Solids (RMS), attained via centrifugation from Canadian dairy farms, were synthesized into a non-polluting fertilizer by bonding micronutrients (Fe, Zn, and Mn) to cellulose fibers and then assessed for the effectiveness of nutrient recovery in tomatoes. Manure management technology is critical for improving the sustainability of agroecosystems and has the capacity to offer a truly circular economy. The ability to add value to manure byproducts offers an opportunity for economic benefits while generating tenable solutions to livestock waste. The dairy industry is under increasing pressure from new environmental protections such as government restrictions on manure applications, limitations on herd size as well as increased product demand from a growing population. Current systems use RMS as bedding, so there is a lack of data pertaining to RMS use as a fertilizer. This is because of nutrient distribution, where most nutrients are retained in the liquid effluent of the solid-liquid separation. A literature review on the physical and chemical properties of dairy manure further revealed more data for raw manure than centrifuged solids. This research offers an innovative perspective and a new avenue of exploration in the use of RMS. Manure solids in this study were obtained directly from dairy farms in Salmon Arm and Abbotsford, British Columbia, and underwent physical, chemical, and biological characterizations pre- and post-synthesis processing. Samples were sent to A&L labs Canada for analysis. Once characterized and bonded to micronutrients, the effect of synthesized RMS on nutrient recovery in tomatoes was studied in a greenhouse environment. The agricultural research package ‘agricolae’ for R was used for experimental design and data analysis. The growth trials consisted of a randomized complete block design (RCBD) that allowed for analysis of variance (ANOVA). The primary outcome was to measure nutrient uptake, and this was done using an Inductively Coupled Plasma Mass Spectrometer (IC-PMS) to analyze the micronutrient content of both the tissue and fruit of the tomatoes. It was found that treatments containing bonded dairy manure solids had an increased micronutrient concentration. Treatments with bonded dairy manure solids also saw an increase in yield, and a brix analysis showed higher sugar content than the untreated control and a grower standard.

Keywords: aoecosystems, dairy manure, micronutrient fertilizer, manure management, nutrient recovery, nutrient recycling, recycled manure solids, regenerative agricugrlture, sustainable farming

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3571 Exploration and Evaluation of the Effect of Multiple Countermeasures on Road Safety

Authors: Atheer Al-Nuaimi, Harry Evdorides

Abstract:

Every day many people die or get disabled or injured on roads around the world, which necessitates more specific treatments for transportation safety issues. International road assessment program (iRAP) model is one of the comprehensive road safety models which accounting for many factors that affect road safety in a cost-effective way in low and middle income countries. In iRAP model road safety has been divided into five star ratings from 1 star (the lowest level) to 5 star (the highest level). These star ratings are based on star rating score which is calculated by iRAP methodology depending on road attributes, traffic volumes and operating speeds. The outcome of iRAP methodology are the treatments that can be used to improve road safety and reduce fatalities and serious injuries (FSI) numbers. These countermeasures can be used separately as a single countermeasure or mix as multiple countermeasures for a location. There is general agreement that the adequacy of a countermeasure is liable to consistent losses when it is utilized as a part of mix with different countermeasures. That is, accident diminishment appraisals of individual countermeasures cannot be easily added together. The iRAP model philosophy makes utilization of a multiple countermeasure adjustment factors to predict diminishments in the effectiveness of road safety countermeasures when more than one countermeasure is chosen. A multiple countermeasure correction factors are figured for every 100-meter segment and for every accident type. However, restrictions of this methodology incorporate a presumable over-estimation in the predicted crash reduction. This study aims to adjust this correction factor by developing new models to calculate the effect of using multiple countermeasures on the number of fatalities for a location or an entire road. Regression models have been used to establish relationships between crash frequencies and the factors that affect their rates. Multiple linear regression, negative binomial regression, and Poisson regression techniques were used to develop models that can address the effectiveness of using multiple countermeasures. Analyses are conducted using The R Project for Statistical Computing showed that a model developed by negative binomial regression technique could give more reliable results of the predicted number of fatalities after the implementation of road safety multiple countermeasures than the results from iRAP model. The results also showed that the negative binomial regression approach gives more precise results in comparison with multiple linear and Poisson regression techniques because of the overdispersion and standard error issues.

Keywords: international road assessment program, negative binomial, road multiple countermeasures, road safety

Procedia PDF Downloads 240
3570 Historical Analysis of Two Types of Urbanization Changing Both the Aspect and Identity of a Town in Transylvania, Romania

Authors: Ágota Ladó

Abstract:

Miercurea Ciuc is a town in the historical region of Szeklerland in Transylvania, Romania, with a predominantly Hungarian population (its name in Hungarian being Csíkszereda) having an urban landscape and environment that has been shaped dramatically by different perceptions of urbanization during the history. The town has been part of Hungary and the Austro-Hungarian Empire before the First World War. It even got an important role, becoming in 1876 the seat and administrative center of the historical Csík county. This marks the beginning of the first urbanization process: new administrative buildings, railways, a railway station, a hospital, a Redoute and new schools have been built, new streets have been opened. However, not only the public facilities have changed: the center of the town with its private houses has also transformed, new, modern decorative and lifestyle elements have appeared. One of the streets from the town center, Kossuth street, has been featured on many postcards of the time; even a novel has mentioned it as a symbol of modern urbanization. Right after the First World War, the town became part of Romania and aside from a short interruption (between 1940 and 1944), it is still part of it. The beginning of the second major urbanization process – exactly one hundred years later - is marked by the visit of the communist leader Nicolae Ceaușescu in Miercurea Ciuc on the 6th of October 1976. In the upcoming years, he decided and started to demolish the old Kossuth street and to construct a new avenue with tall blocks of flats according to the principles of socialist urbanization. No other Transylvanian settlement has gone through such systematic abolition of its historical center and urban history during the Communist era. Not only the urban landscape has been affected. The collective memory and contemporary identity of the locals are also violated by this recent transformation of the town: important spaces, buildings, venues of activities and events simply cannot be localized, thus understood - by the younger generations.

Keywords: communist era, historical urban landscape, urban identity, urbanization

Procedia PDF Downloads 179
3569 Calculation of Lungs Physiological Lung Motion in External Lung Irradiation

Authors: Yousif Mohamed Y. Abdallah, Khalid H. Eltom

Abstract:

This is an experimental study deals with measurement of the periodic physiological organ motion during lung external irradiation in order to reduce the exposure of healthy tissue during radiation treatments. The results showed for left lung displacement reading (4.52+1.99 mm) and right lung is (8.21+3.77 mm) which the radiotherapy physician should take suitable countermeasures in case of significant errors. The motion ranged between 2.13 mm and 12.2 mm (low and high). In conclusion, the calculation of tumour mobility can improve the accuracy of target areas definition in patients undergo Sterostatic RT for stage I, II and III lung cancer (NSCLC). Definition of the target volume based on a high resolution CT scan with a margin of 3-5 mm is appropriate.

Keywords: physiological motion, lung, external irradiation, radiation medicine

Procedia PDF Downloads 417
3568 A Review of Emerging Technologies in Antennas and Phased Arrays for Avionics Systems

Authors: Muhammad Safi, Abdul Manan

Abstract:

In recent years, research in aircraft avionics systems (i.e., radars and antennas) has grown revolutionary. Aircraft technology is experiencing an increasing inclination from all mechanical to all electrical aircraft, with the introduction of inhabitant air vehicles and drone taxis over the last few years. This develops an overriding need to summarize the history, latest trends, and future development in aircraft avionics research for a better understanding and development of new technologies in the domain of avionics systems. This paper focuses on the future trends in antennas and phased arrays for avionics systems. Along with the general overview of the future avionics trend, this work describes the review of around 50 high-quality research papers on aircraft communication systems. Electric-powered aircraft have been a hot topic in the modern aircraft world. Electric aircraft have supremacy over their conventional counterparts. Due to increased drone taxi and urban air mobility, fast and reliable communication is very important, so concepts of Broadband Integrated Digital Avionics Information Exchange Networks (B-IDAIENs) and Modular Avionics are being researched for better communication of future aircraft. A Ku-band phased array antenna based on a modular design can be used in a modular avionics system. Furthermore, integrated avionics is also emerging research in future avionics. The main focus of work in future avionics will be using integrated modular avionics and infra-red phased array antennas, which are discussed in detail in this paper. Other work such as reconfigurable antennas and optical communication, are also discussed in this paper. The future of modern aircraft avionics would be based on integrated modulated avionics and small artificial intelligence-based antennas. Optical and infrared communication will also replace microwave frequencies.

Keywords: AI, avionics systems, communication, electric aircrafts, infra-red, integrated avionics, modular avionics, phased array, reconfigurable antenna, UAVs

Procedia PDF Downloads 81
3567 Mental Health Clinicians’ Perceptions of Nature-Based Interventions Within Community Mental Health Services: Evidence from Australia

Authors: Rachel Tambyah, Katarzyna Olcoń, Julaine Allan, Pete Destry, Thomas Astell-Burt

Abstract:

The rising social and financial burden of mental illness indicates an urgent need to explore interventions that can be used as well as or instead of traditional treatments. Although there is growing evidence of the positive mental health outcomes of spending time in nature, the implementation of nature-based interventions (NBIs) within mental health services remains minimal. Based on interviews with mental health clinicians in Australia, this study demonstrated that clinicians supported the use of NBIs and would promote them to their clients.

Keywords: nature, nature-based interventions, mental health, mental health services, mental health clinicians

Procedia PDF Downloads 148
3566 Finite Element Modeling and Analysis of Reinforced Concrete Coupled Shear Walls Strengthened with Externally Bonded Carbon Fiber Reinforced Polymer Composites

Authors: Sara Honarparast, Omar Chaallal

Abstract:

Reinforced concrete (RC) coupled shear walls (CSWs) are very effective structural systems in resisting lateral loads due to winds and earthquakes and are particularly used in medium- to high-rise RC buildings. However, most of existing old RC structures were designed for gravity loads or lateral loads well below the loads specified in the current modern seismic international codes. These structures may behave in non-ductile manner due to poorly designed joints, insufficient shear reinforcement and inadequate anchorage length of the reinforcing bars. This has been the main impetus to investigate an appropriate strengthening method to address or attenuate the deficiencies of these structures. The objective of this paper is to twofold: (i) evaluate the seismic performance of existing reinforced concrete coupled shear walls under reversed cyclic loading; and (ii) investigate the seismic performance of RC CSWs strengthened with externally bonded (EB) carbon fiber reinforced polymer (CFRP) sheets. To this end, two CSWs were considered as follows: (a) the first one is representative of old CSWs and therefore was designed according to the 1941 National Building Code of Canada (NBCC, 1941) with conventionally reinforced coupling beams; and (b) the second one, representative of new CSWs, was designed according to modern NBCC 2015 and CSA/A23.3 2014 requirements with diagonally reinforced coupling beam. Both CSWs were simulated using ANSYS software. Nonlinear behavior of concrete is modeled using multilinear isotropic hardening through a multilinear stress strain curve. The elastic-perfectly plastic stress-strain curve is used to simulate the steel material. Bond stress–slip is modeled between concrete and steel reinforcement in conventional coupling beam rather than considering perfect bond to better represent the slip of the steel bars observed in the coupling beams of these CSWs. The old-designed CSW was strengthened using CFRP sheets bonded to the concrete substrate and the interface was modeled using an adhesive layer. The behavior of CFRP material is considered linear elastic up to failure. After simulating the loading and boundary conditions, the specimens are analyzed under reversed cyclic loading. The comparison of results obtained for the two unstrengthened CSWs and the one retrofitted with EB CFRP sheets reveals that the strengthening method improves the seismic performance in terms of strength, ductility, and energy dissipation capacity.

Keywords: carbon fiber reinforced polymer, coupled shear wall, coupling beam, finite element analysis, modern code, old code, strengthening

Procedia PDF Downloads 197
3565 Computational Approach to the Interaction of Neurotoxins and Kv1.3 Channel

Authors: Janneth González, George Barreto, Ludis Morales, Angélica Sabogal

Abstract:

Sea anemone neurotoxins are peptides that interact with Na+ and K+ channels, resulting in specific alterations on their functions. Some of these neurotoxins (1ROO, 1BGK, 2K9E, 1BEI) are important for the treatment of nearly eighty autoimmune disorders due to their specificity for Kv1.3 channel. The aim of this study was to identify the common residues among these neurotoxins by computational methods, and establish whether there is a pattern useful for the future generation of a treatment for autoimmune diseases. Our results showed eight new key common residues between the studied neurotoxins interacting with a histidine ring and the selectivity filter of the receptor, thus showing a possible pattern of interaction. This knowledge may serve as an input for the design of more promising drugs for autoimmune treatments.

Keywords: neurotoxins, potassium channel, Kv1.3, computational methods, autoimmune diseases

Procedia PDF Downloads 374
3564 Interpreting Ecclesiastical Heritage: Meaning Making and Contentious Conversations

Authors: Alexis Thouki

Abstract:

In our post-Christian societies, ecclesiastical heritage acquired a new extrovert profile aiming to reach out an increasingly diverse audience. In this context, the various motivations, interests, personalities and cultural exchanges, found in the ‘post-modern pilgrimage’, bequeath a hybrid and multidimensional character to religious tourism education. In consequence, churches have acquired the challenging role of enriching visitors cultural and spiritual capital. Despite this promising diversification to relate, reveal and provoke constructive discourses, due to the various ‘conflicting interests’, practitioners attempt to tame the rich in symbolism and meanings religious environment through ‘neutral interpretations’. This paper aims to present the results of an ongoing developing strategy related to the presentation of contentious meanings in English churches. The paper will explore some of the underlying issues related to the capacity of ‘neutrality’ to spark, downplay or eliminate contentious conversations relating to the cultural, religious, and social dimension of Christian cultural heritage thematology. In an effort to understand this issue, the paper examines the concept of neutrality and what it stands for, executing a discourse analysis in the semantic context in which the theological lexicon is interwoven with the cultural and social meanings of sacred sites. Following that, the paper examines whether the preferable interpretive strategies meet the post-modern interpretative framework which is marked by polysemy and critical active engagement. The ultimate aim of the paper is to investigate the hypothesis that the preferable neutral strategies, managing the ‘conflicting’ demands of worshippers and visitors, result in the uneven treatment of both, the religious and historical spirit of the place.

Keywords: contentious dialogue, interpretation, meaning making, religious tourism

Procedia PDF Downloads 156
3563 Evaluation of the Photo Neutron Contamination inside and outside of Treatment Room for High Energy Elekta Synergy® Linear Accelerator

Authors: Sharib Ahmed, Mansoor Rafi, Kamran Ali Awan, Faraz Khaskhali, Amir Maqbool, Altaf Hashmi

Abstract:

Medical linear accelerators (LINAC’s) used in radiotherapy treatments produce undesired neutrons when they are operated at energies above 8 MeV, both in electron and photon configuration. Neutrons are produced by high-energy photons and electrons through electronuclear (e, n) a photonuclear giant dipole resonance (GDR) reactions. These reactions occurs when incoming photon or electron incident through the various materials of target, flattening filter, collimators, and other shielding components in LINAC’s structure. These neutrons may reach directly to the patient, or they may interact with the surrounding materials until they become thermalized. A work has been set up to study the effect of different parameter on the production of neutron around the room by photonuclear reactions induced by photons above ~8 MeV. One of the commercial available neutron detector (Ludlum Model 42-31H Neutron Detector) is used for the detection of thermal and fast neutrons (0.025 eV to approximately 12 MeV) inside and outside of the treatment room. Measurements were performed for different field sizes at 100 cm source to surface distance (SSD) of detector, at different distances from the isocenter and at the place of primary and secondary walls. Other measurements were performed at door and treatment console for the potential radiation safety concerns of the therapists who must walk in and out of the room for the treatments. Exposures have taken place from Elekta Synergy® linear accelerators for two different energies (10 MV and 18 MV) for a given 200 MU’s and dose rate of 600 MU per minute. Results indicates that neutron doses at 100 cm SSD depend on accelerator characteristics means jaw settings as jaws are made of high atomic number material so provides significant interaction of photons to produce neutrons, while doses at the place of larger distance from isocenter are strongly influenced by the treatment room geometry and backscattering from the walls cause a greater doses as compare to dose at 100 cm distance from isocenter. In the treatment room the ambient dose equivalent due to photons produced during decay of activation nuclei varies from 4.22 mSv.h−1 to 13.2 mSv.h−1 (at isocenter),6.21 mSv.h−1 to 29.2 mSv.h−1 (primary wall) and 8.73 mSv.h−1 to 37.2 mSv.h−1 (secondary wall) for 10 and 18 MV respectively. The ambient dose equivalent for neutrons at door is 5 μSv.h−1 to 2 μSv.h−1 while at treatment console room it is 2 μSv.h−1 to 0 μSv.h−1 for 10 and 18 MV respectively which shows that a 2 m thick and 5m longer concrete maze provides sufficient shielding for neutron at door as well as at treatment console for 10 and 18 MV photons.

Keywords: equivalent doses, neutron contamination, neutron detector, photon energy

Procedia PDF Downloads 449
3562 Nanowire Sensor Based on Novel Impedance Spectroscopy Approach

Authors: Valeriy M. Kondratev, Ekaterina A. Vyacheslavova, Talgat Shugabaev, Alexander S. Gudovskikh, Alexey D. Bolshakov

Abstract:

Modern sensorics imposes strict requirements on the biosensors characteristics, especially technological feasibility, and selectivity. There is a growing interest in the analysis of human health biological markers, which indirectly testifying the pathological processes in the body. Such markers are acids and alkalis produced by the human, in particular - ammonia and hydrochloric acid, which are found in human sweat, blood, and urine, as well as in gastric juice. Biosensors based on modern nanomaterials, especially low dimensional, can be used for this markers detection. Most classical adsorption sensors based on metal and silicon oxides are considered non-selective, because they identically change their electrical resistance (or impedance) under the action of adsorption of different target analytes. This work demonstrates a feasible frequency-resistive method of electrical impedance spectroscopy data analysis. The approach allows to obtain of selectivity in adsorption sensors of a resistive type. The method potential is demonstrated with analyzis of impedance spectra of silicon nanowires in the presence of NH3 and HCl vapors with concentrations of about 125 mmol/L (2 ppm) and water vapor. We demonstrate the possibility of unambiguous distinction of the sensory signal from NH3 and HCl adsorption. Moreover, the method is found applicable for analysis of the composition of ammonia and hydrochloric acid vapors mixture without water cross-sensitivity. Presented silicon sensor can be used to find diseases of the gastrointestinal tract by the qualitative and quantitative detection of ammonia and hydrochloric acid content in biological samples. The method of data analysis can be directly translated to other nanomaterials to analyze their applicability in the field of biosensory.

Keywords: electrical impedance spectroscopy, spectroscopy data analysis, selective adsorption sensor, nanotechnology

Procedia PDF Downloads 114
3561 Object-Oriented Modeling Simulation and Control of Activated Sludge Process

Authors: J. Fernandez de Canete, P. Del Saz Orozco, I. Garcia-Moral, A. Akhrymenka

Abstract:

Object-oriented modeling is spreading in current simulation of wastewater treatments plants through the use of the individual components of the process and its relations to define the underlying dynamic equations. In this paper, we describe the use of the free-software OpenModelica simulation environment for the object-oriented modeling of an activated sludge process under feedback control. The performance of the controlled system was analyzed both under normal conditions and in the presence of disturbances. The object-oriented described approach represents a valuable tool in teaching provides a practical insight in wastewater process control field.

Keywords: object-oriented programming, activated sludge process, OpenModelica, feedback control

Procedia PDF Downloads 386
3560 Flexural Properties of Typha Fibers Reinforced Polyester Composite

Authors: Sana Rezig, Yosr Ben Mlik, Mounir Jaouadi, Foued Khoffi, Slah Msahli, Bernard Durand

Abstract:

Increasing interest in environmental concerns, natural fibers are once again being considered as reinforcements for polymer composites. The main objective of this study is to explore another natural resource, Typha fiber; which is renewable without production cost and available abundantly in nature. The aim of this study was to study the flexural properties of composite resin with and without reinforcing Typha leaf and stem fibers. The specimens were made by the hand-lay-up process using polyester matrix. In our work, we focused on the effect of various treatment conditions (sea water, alkali treatment and a combination of the two treatments), as a surface modifier, on the flexural properties of the Typha fibers reinforced polyester composites. Moreover, weight ratio of Typha leaf or stem fibers was investigated. Besides, both fibers from leaf and stem of Typha plant were used to evaluate the reinforcing effect. Another parameter, which is reinforcement structure, was investigated. In fact, a first composite was made with air-laid nonwoven structure of fibers. A second composite was with a mixture of fibers and resin for each kind of treatment. Results show that alkali treatment and combined process provided better mechanical properties of composites in comparison with fiber treated by sea water. The fiber weight ratio influenced the flexural properties of composites. Indeed, a maximum value of flexural strength of 69.8 and 62,32 MPa with flexural modulus of 6.16 and 6.34 GPawas observed respectively for composite reinforced with leaf and stem fibers for 12.6 % fiber weight ratio. For the different treatments carried out, the treatment using caustic soda, whether alone or after retting seawater, show the best results because it improves adhesion between the polyester matrix and the fibers of reinforcement. SEM photographs were made to ascertain the effects of the surface treatment of the fibers. By varying the structure of the fibers of Typha, the reinforcement used in bulk shows more effective results as that used in the non-woven structure. In addition, flexural strength rises with about (65.32 %) in the case of composite reinforced with a mixture of 12.6% leaf fibers and (27.45 %) in the case of a composite reinforced with a nonwoven structure of 12.6 % of leaf fibers. Thus, to better evaluate the effect of the fiber origin, the reinforcing structure, the processing performed and the reinforcement factor on the performance of composite materials, a statistical study was performed using Minitab. Thus, ANOVA was used, and the patterns of the main effects of these parameters and interaction between them were established. Statistical analysis, the fiber treatment and reinforcement structure seem to be the most significant parameters.

Keywords: flexural properties, fiber treatment, structure and weight ratio, SEM photographs, Typha leaf and stem fibers

Procedia PDF Downloads 415
3559 Design and Development of High Strength Aluminium Alloy from Recycled 7xxx-Series Material Using Bayesian Optimisation

Authors: Alireza Vahid, Santu Rana, Sunil Gupta, Pratibha Vellanki, Svetha Venkatesh, Thomas Dorin

Abstract:

Aluminum is the preferred material for lightweight applications and its alloys are constantly improving. The high strength 7xxx alloys have been extensively used for structural components in aerospace and automobile industries for the past 50 years. In the next decade, a great number of airplanes will be retired, providing an obvious source of valuable used metals and great demand for cost-effective methods to re-use these alloys. The design of proper aerospace alloys is primarily based on optimizing strength and ductility, both of which can be improved by controlling the additional alloying elements as well as heat treatment conditions. In this project, we explore the design of high-performance alloys with 7xxx as a base material. These designed alloys have to be optimized and improved to compare with modern 7xxx-series alloys and to remain competitive for aircraft manufacturing. Aerospace alloys are extremely complex with multiple alloying elements and numerous processing steps making optimization often intensive and costly. In the present study, we used Bayesian optimization algorithm, a well-known adaptive design strategy, to optimize this multi-variable system. An Al alloy was proposed and the relevant heat treatment schedules were optimized, using the tensile yield strength as the output to maximize. The designed alloy has a maximum yield strength and ultimate tensile strength of more than 730 and 760 MPa, respectively, and is thus comparable to the modern high strength 7xxx-series alloys. The microstructure of this alloy is characterized by electron microscopy, indicating that the increased strength of the alloy is due to the presence of a high number density of refined precipitates.

Keywords: aluminum alloys, Bayesian optimization, heat treatment, tensile properties

Procedia PDF Downloads 119