Search results for: contemporary conditions

Authors: G. Guramishvili, M. Moistsrapishvili, L. Andghuladze

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In the article are considered the problems arising at increasing of transferring from rolling stock axles on rail loading from 210 KN up to 270 KN and is offered for rail strength analysis definition of rail force loading complex integral characteristic with taking into account all affecting force factors that is characterizing specific operation condition of rail structure and defines the working capability of structure. As result of analysis due mentioned method is obtained that in the conditions of 270 KN loading the rail meets the working assessment criteria of rail and rail structures: Strength, rail track stability, rail links stability and its transverse stability, traffic safety condition that is rather important for post-Soviet countries railways.

Keywords: axial loading, rail force loading, rail structure, rail strength analysis, rail track stability

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Authors: Elineuda Do Socorro Santos Picanço Sousa, Ana Kerlly Souza da Costa

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This paper presents the analysis of the information society as a plural, inclusive and participatory society, where it is necessary to give all citizens, especially young people, the right skills in order to develop skills so that they can understand and use information through of contemporary technologies; well as carry out a critical analysis, using and producing information and all sorts of messages and / or informational language codes. This conviction inspired this article, whose aim is to present current trends in the use of technology in distance education applied as an alternative and / or supplement to classroom teaching for Youth and Adults, concepts and actions, seeking to contribute to its development in the state of Amapá and specifically, the Center for Professional of Amapá Teaching Professor Josinete Oliveira Barroso - CEPAJOB.

Keywords: youth and adults education, Ead. Professional Education, online courses, CEPAJOB

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Authors: Ali Reza Tahavvor, Saeed Hosseini, Nazli Jowkar, Behnam Amiri

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Heat transfer of leaves is a crucial factor in optimal operation of metabolic functions in plants. In order to quantify this phenomenon in different leaves and investigate the influence of leaf shape on heat transfer, natural convection for pine, orange and olive leaves was simulated as representatives of different groups of leaf shapes. CFD techniques were used in this simulation with the purpose to calculate heat transfer of leaves in similar environmental conditions. The problem was simulated for steady state and three-dimensional conditions. From obtained results, it was concluded that heat fluxes of all three different leaves are almost identical, however, total rate of heat transfer have highest and lowest values for orange leaves and pine leaves, respectively.

Keywords: computational fluid dynamic, heat flux, heat transfer, natural convection

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Authors: Sergei Aleinik, Mikhail Stolbov

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In this work, a method of time delay estimation for dual-channel acoustic signals (speech, music, etc.) recorded under reverberant conditions is investigated. Standard methods based on cross-correlation of the signals show poor results in cases involving strong reverberation, large distances between microphones and asynchronous recordings. Under similar conditions, a method based on cross-correlation of temporal envelopes of the signals delivers a delay estimation of acceptable quality. This method and its properties are described and investigated in detail, including its limits of applicability. The method’s optimal parameter estimation and a comparison with other known methods of time delay estimation are also provided.

Keywords: cross-correlation, delay estimation, signal envelope, signal processing

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Authors: Somnath Karmakar, S. Chakraverty

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This work investigates the vibration of nonhomogeneous Timoshenko nanobeam resting on the Winkler-Pasternak foundation. Eringen’s nonlocal theory has been used to investigate small-scale effects. The Differential Quadrature method is used to obtain the frequency parameters with various classical boundary conditions. The nonhomogeneous beam model has been considered, where Young’s modulus and density of the beam material vary linearly and quadratically. Convergence of frequency parameters is also discussed. The influence of mechanical properties and scaling parameters on vibration frequencies are investigated for different boundary conditions.

Keywords: Timoshenko beam, Eringen's nonlocal theory, differential quadrature method, nonhomogeneous nanobeam

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Authors: Živa Ravnikar, Alfonso Bahillo Martinez, Barbara Goličnik Marušić

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Climate change mitigation has been formally adopted and announced by countries over the globe, where cities are targeting carbon neutrality through various more or less successful, systematic, and fragmentary actions. The article is based on the fact that environmental conditions affect human comfort and the usage of space. Urban planning can, with its sustainable solutions, not only support climate mitigation in terms of a planet reduction of global warming but as well enabling natural processes that in the immediate vicinity produce environmental conditions that encourage people to walk or cycle. However, the article draws attention to the importance of integrating climate consideration into urban planning, where detailed environmental data play a key role, enabling urban planners to improve or monitor environmental conditions on cycle paths. In a practical aspect, this paper tests a particular ICT tool, a prototype used for environmental data. Data gathering was performed along the cycling lanes in Ljubljana (Slovenia), where the main objective was to assess the tool's data applicable value within the planning of comfortable cycling lanes. The results suggest that such transportable devices for in-situ measurements can help a researcher interpret detailed environmental information, characterized by fine granularity and precise data spatial and temporal resolution. Data can be interpreted within human comfort zones, where graphical representation is in the form of a map, enabling the link of the environmental conditions with a spatial context. The paper also provides preliminary results in terms of the potential of such tools for identifying the correlations between environmental conditions and different spatial settings, which can help urban planners to prioritize interventions in places. The paper contributes to multidisciplinary approaches as it demonstrates the usefulness of such fine-grained data for better consideration of microclimatology in urban planning, which is a prerequisite for creating climate-comfortable cycling lanes promoting active mobility.

Keywords: information and communication technology tools, urban planning, human comfort, microclimate, cycling lanes

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Authors: Luigi Pintacuda

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What characterize the phenomenology of Bucharest is that all operations of modernization have never been completed, creating a city made up of fragments. Understood this fragmented nature, the traces and fractures, the acceptance of their scars must represent the basis for the design of development for Bucharest. From this insight comes a new analysis of this city: a city of two million inhabitants that does not need a project on an urban scale (as all other major projects for the city have failed), but, starting from the study of all these interstitial spaces of public property, it must find its own strategy, a strategy on a large-scale that reflects on the sites on an architectural one. It is a city composed by fragments, not waste, but places for the project: ‘waiting spaces’ for a possible continuation of the process of genesis of a city which is often incomplete.

Keywords: public spaces, traces fractures, urban design, urban development

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Authors: Zehra Aytac, Nurdilek Gulmezoglu

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Safflower has been grown for centuries for many purposes worldwide. Especially it is important for the orange-red dye from its petal and for its high-quality oil obtained from the seeds. The crop is high adaptable to areas with insufficient rainfall and poor soil conditions. The plant has a deep taproot that can draw moisture and plant nutrients from deep to the subsoil. The research was carried out to study the nitrogen (N) uptake of different safflower cultivars and lines at different stages of growth and different plant parts in the experimental field of Faculty of Agriculture, Eskişehir Osmangazi University under semi-arid conditions. Different safflower cultivars and lines of varied origins were used as the material. The cultivars and lines were planted in a Randomized Complete Block Design with three replications. Two different growth stages (flowering and harvest) and three different plant parts (head, stem+leaf and seed) were determined. The nitrogen concentration of different plant parts was determined by the Kjeldahl method. Statistical analysis were performed by analysis of variance for each growth stage and plant parts taking a level of p < 0.05 and p < 0.01 as significant according to the LSD test. As a result, N concentration showed significant differences among different plant parts and different growth stages for different safflower genotypes of varied origins.

Keywords: Carthamus tinctorius L., growth stages, head N, leaf N, N uptake, seed N, Safflower

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Authors: Masoud Shahmanzari

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The aim of this paper is to present a Variable Neighborhood Search (VNS) with Tabu Search (TS) conditions for the Roaming Salesman Problem (RSP). The RSP is a special case of the well-known traveling salesman problem (TSP) where a set of cities with time-dependent rewards and a set of campaign days are given. Each city can be visited on any day and a subset of cities can be visited multiple times. The goal is to determine an optimal campaign schedule consist of daily open/closed tours that visit some cities and maximizes the total net benefit while respecting daily maximum tour duration constraints and the necessity to return campaign base frequently. This problem arises in several real-life applications and particularly in election logistics where depots are not fixed. We formulate the problem as a mixed integer linear programming (MILP), in which we capture as many real-world aspects of the RSP as possible. We also present a hybrid metaheuristic algorithm based on a VNS with TS conditions. The initial feasible solution is constructed via a new matheuristc approach based on the decomposition of the original problem. Next, this solution is improved in terms of the collected rewards using the proposed local search procedure. We consider a set of 81 cities in Turkey and a campaign of 30 days as our largest instance. Computational results on real-world instances show that the developed algorithm could find near-optimal solutions effectively.

Keywords: optimization, routing, election logistics, heuristics

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Authors: Julia Wimmers-Klick

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In the contemporary study of anatomy, medical students utilize a diverse array of resources, including lab handouts, lectures, and, increasingly, digital media such as interactive anatomy apps and digital images. Notably, a significant shift has occurred, with fewer students possessing traditional anatomy atlases or books, reflecting a broader trend towards digital approaches like Virtual Reality, Augmented Reality, and web-based programs. This paper seeks to explore the evolution of anatomy education by contrasting current digital tools with historical resources, such as classical anatomical illustrations and atlases, to assess their relevance and potential benefits in modern medical education. Through a comprehensive literature review, the development of anatomical illustrations is traced from the textual descriptions of Galen to the detailed and artistic representations of Da Vinci, Vesalius, and later anatomists. The examination includes how the printing press facilitated the dissemination of anatomical knowledge, transforming covert dissections into public spectacles and formalized teaching practices. Historical illustrations, often influenced by societal, religious, and aesthetic contexts, not only served educational purposes but also reflected the prevailing medical knowledge and ethical standards of their times. Critical questions are raised about the place of historical illustrations in today's anatomy curriculum. Specifically, their potential to teach critical thinking, highlight the history of medicine, and offer unique insights into past societal conditions are explored. These resources are viewed in their context, including the lack of diversity and the presence of ethical concerns, such as the use of illustrations from unethical sources like Pernkopf’s atlas. In conclusion, while digital tools offer innovative ways to visualize and interact with anatomical structures, historical illustrations provide irreplaceable value in understanding the evolution of medical knowledge and practice. The study advocates for a balanced approach that integrates traditional and modern resources to enrich medical education, promote critical thinking, and provide a comprehensive understanding of anatomy. Future research should investigate the optimal combination of these resources to meet the evolving needs of medical learners and the implications of the digital shift in anatomy education.

Keywords: human anatomy, historical illustrations, historical context, medical education

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Authors: S. Srikiran, Dharmala Venkata Padmaja, P. N. L. Pavani, R. Pola Rao, K. Ramji

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Technological advancements in the development of cutting tools and coolant/lubricant chemistry have enhanced the machining capabilities of hard materials under higher machining conditions. Generation of high temperatures at the cutting zone during machining is one of the most important and pertinent problems which adversely affect the tool life and surface finish of the machined components. Generally, cutting fluids and solid lubricants are used to overcome the problem of heat generation, which is not effectively addressing the problems. With technological advancements in the field of tribology, nano-level particulate solid lubricants are being used nowadays in machining operations, especially in the areas of turning and grinding. The present investigation analyses the effect of using nano-particulate graphite powder as lubricant in the turning of AISI 1040 steel under variable machining conditions and to study its effect on cutting forces, tool temperature and surface roughness of the machined component. Experiments revealed that the increase in cutting forces and tool temperature resulting in the decrease of surface quality with the decrease in the size of nano-particulate graphite powder as lubricant.

Keywords: solid lubricant, graphite, minimum quantity lubrication (MQL), nano–particles

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Authors: Pratik Pankaj Pawar

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Lightweight structures - structures with reduced weight, which otherwise retain the qualities necessary for the building performance, ensuring proper durability and strength, safety, indoor environmental quality, and energy efficiency; structures that strive for the optimization of structural systems - are in tune with current trends and socio-economic, environmental, and technological factors. The growing interest in lightweight structures design makes them an ever more significant field of research. This article focuses on the architectural aspects of lightweight structures and on their contemporary and future applications. The selected advanced building technologies - i.e., Ultra-High-Performance Concrete, fabrics, and flexible photovoltaics.

Keywords: light weight building, carbyne, aerographite, geopolymer reinforced wood particles aggregate

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Authors: Carolina Brandão Piva

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In our visual culture, images play a newly significant role in the basis of a complex dialogue between imagination, creativity, and social practice. Insofar as imagination has broken out of the 'special expressive space of art' to become a part of the quotidian mental work of ordinary people, it is pertinent to recognize that visual representation can no longer be assumed as if in a domain detached from everyday life or exclusively 'centered' within the limited frame of 'art history.' The approach of Visual Culture as a field of study is, in this sense, indispensable to comprehend that not only 'the image,' but also 'the imagined' and 'the imaginary' are produced in the plurality of social interactions; crucial enough, this assertion directs us to something new in contemporary cultural processes, namely both imagination and image production constitute a social practice. This paper starts off with this approach and seeks to examine the artistic practice of two women from the State of Goiás, Brazil, who are ordinary citizens with their daily activities and narratives but also dedicated to visuality production. With no formal training from art schools, branded or otherwise, Maria Aparecida de Souza Pires deploys 'waste disposal' of daily life—from car tires to old work clothes—as a trampoline for art; also adept at sourcing raw materials collected from her surroundings, she manipulates raw hewn wood, tree trunks, plant life, and various other pieces she collects from nature giving them new meaning and possibility. Hilda Freire works with sculptures in clay using different scales and styles; her art focuses on representations of women and pays homage to unprivileged groups such as the practitioners of African-Brazilian religions, blue-collar workers, poor live-in housekeepers, and so forth. Although they have never been acknowledged by any mainstream art institution in Brazil, whose 'criterion of value' still favors formally trained artists, Maria Aparecida de Souza Pires, and Hilda Freire have produced visualities that instigate 'new ways of seeing,' meriting cultural significance in many ways. Their artworks neither descend from a 'traditional' medium nor depend on 'canonical viewing settings' of visual representation; rather, they consist in producing relationships with the world which do not result in 'seeing more,' but 'at least differently.' From this perspective, the paper finally demonstrates that grouping this kind of artistic production under the label of 'mere craft' has much more to do with who is privileged within the fields of power in art system, who we see and who we do not see, and whose imagination of what is fed by which visual images in Brazilian contemporary society.

Keywords: visual culture, artistic practice, women's art in the Brazilian State of Goiás, Maria Aparecida de Souza Pires, Hilda Freire

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Authors: K. E. Ch. Vidyasagar, M. Moghavvemi, T. S. S. T. Prabhat

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Epilepsy is a global problem, and with seizures eluding even the smartest of diagnoses a requirement for automatic detection of the same using electroencephalogram (EEG) would have a huge impact in diagnosis of the disorder. Among a multitude of methods for automatic epilepsy detection, one should find the best method out, based on accuracy, for classification. This paper reasons out, and rationalizes, the best methods for classification. Accuracy is based on the classifier, and thus this paper discusses classifiers like quadratic discriminant analysis (QDA), classification and regression tree (CART), support vector machine (SVM), naive Bayes classifier (NBC), linear discriminant analysis (LDA), K-nearest neighbor (KNN) and artificial neural networks (ANN). Results show that ANN is the most accurate of all the above stated classifiers with 97.7% accuracy, 97.25% specificity and 98.28% sensitivity in its merit. This is followed closely by SVM with 1% variation in result. These results would certainly help researchers choose the best classifier for detection of epilepsy.

Keywords: classification, seizure, KNN, SVM, LDA, ANN, epilepsy

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Authors: Harish Ramesh Babu, Marco Böcker, Mario Raddatz, Sebastian Henkel, Horst Biermann, Uwe Gampe

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Thermal power machines are subjected to cyclic loading conditions under elevated temperatures. At these extreme conditions, the durability of the components has a significant influence. The material mechanical behaviour has to be known in detail for a failsafe construction. For this study a nickel-based alloy is considered, the deformation and fatigue behaviour of the material is analysed under cyclic loading. A viscoplastic model is used for calculating the deformation behaviour as well as to simulate the rate-dependent and cyclic plasticity effects. Finally, the cyclic deformation results of the finite element simulations are compared with low cycle fatigue (LCF) experiments.

Keywords: complex low cycle fatigue, elevated temperature, fe-simulation, viscoplastic

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Authors: Federico Pittino, Thomas Arnold

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The shredding of waste materials is a key step in the recycling process towards the circular economy. Industrial shredders for waste processing operate in very harsh operating conditions, leading to the need for frequent maintenance of critical components. Maintenance optimization is particularly important also to increase the machine’s efficiency, thereby reducing the operational costs. In this work, a monitoring system has been developed and deployed on an industrial shredder located at a waste recycling plant in Austria. The machine has been monitored for one year, and methods for predictive maintenance have been developed for two key components: the cutting knives and the drive belt. The large amount of collected data is leveraged by statistical machine learning techniques, thereby not requiring very detailed knowledge of the machine or its live operating conditions. The results show that, despite the wide range of operating conditions, a reliable estimate of the optimal time for maintenance can be derived. Moreover, the trade-off between the cost of maintenance and the increase in power consumption due to the wear state of the monitored components of the machine is investigated. This work proves the benefits of real-time monitoring system for the efficient operation of industrial shredders.

Keywords: predictive maintenance, circular economy, industrial shredder, cost optimization, statistical machine learning

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Authors: S. Sunaina, Neha Saini

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Children are considered as future of a country. In order to have a better future, better laws are required in the present, especially for the children. Their development primarily revolves around physical, mental, psychological, emotional and financial facets. Hence the holistic development of a child in the contemporary society is a must in order to secure a better future. The present paper is an endeavour to analyse the development of children in India vis-a-vis The Child Development Bill 2016 and Child Labour (Abolition) Bill 2016 pending before the Indian Parliament. The findings of the study will attempt to highlight the flaws of the Bills and their probable repercussions, supporting the same with Constitutional provisions, judicial precedents, and the international perspective. Finally, the paper will conclude with concrete suggestions to overcome the flaws of the Bills so that the Bills, when passed, can be sincerely implemented.

Keywords: bill, children, development, repercussion

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Authors: V. Prasannavenkadesan, A. Elango, S. Chockalingam

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During machining process, chatter is an unavoidable phenomenon. Boring bars possess the cantilever shape and due to this, it is subjected to chatter. The adverse effect of chatter includes the increase in temperature which will leads to excess tool wear. To overcome these problems, in this investigation, Cartridge brass (Cu – 70% and Zn – 30%) is passively fixed on the boring bar and also clearance is provided in order to reduce the displacement, tool wear and cutting temperature. A conventional all geared lathe is attached with vibrometer and pyrometer is used to measure the displacement and temperature. The influence of input parameters such as cutting speed, depth of cut and clearance on temperature, tool wear and displacement are investigated for various cutting conditions. From the result, the optimum conditions to obtain better damping in boring process for chatter reduction is identified.

Keywords: boring, chatter, mass damping, passive damping

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Authors: M. Şahi̇n, E. Erdem, M. Saçak

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In this study, Na-smectite crystals purificated of bentonite were used after being swelling with benzyltributylammonium bromide (BTBAB) as alkyl ammonium salt. Swelling process was carried out using 0.2 g of BTBAB for smectite of 0.8 g with 4 h of mixing time after investigated conditions such as mixing time, the swelling agent amount. Then, the conductive poly(o-anisidine) (POA)/smectite nanocomposite was prepared in the presence of swollen Na-smectite using ammonium persulfate (APS) as oxidant in aqueous acidic medium. The POA content and conductivity of the prepared nanocomposite were systematically investigated as a function of polymerization conditions such as the treatment time of swollen smectite in monomer solution and o-anisidine/APS mol ratio. POA/smectite nanocomposite was characterized by XRD, FTIR and SEM techniques and was compared separately with components of composite.

Keywords: clay, composite, conducting polymer, poly(o-anisidine)

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Authors: Xu Runzhang, Yang Yanbing, Niu Yi, Zhang Mingyou, Liu Yu

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For a class of semilinear parabolic equations with linear dynamical boundary conditions in a bounded domain, we obtain both global solutions and finite time blow-up solutions when the initial data varies in the phase space H1(Ω). Our main tools are the comparison principle, the potential well method and the concavity method. In particular, we discuss the behavior of the solutions with the initial data at critical and high energy level.

Keywords: high energy level, critical energy level, linear dynamical boundary condition, semilinear parabolic equation

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Authors: Muhammad Afzal Malik

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Traditional Learning & Distance based learning are the two systems prevailing in Pakistan. These systems affect the level of education standard. The purpose of this study was to compare the traditional classroom learning and distance learning in Pakistan: (a) To explore the effectiveness of the traditional to Distance learning in Pakistan; (b) To identify the factors that affect traditional and distance learning. This review found that, on average, students in traditional classroom conditions performed better than those receiving education in and distance learning. The difference between student outcomes for traditional Classroom and distance learning classes —measured as the difference between treatment and control means, divided by the pooled standard deviation— was larger in those studies contrasting conditions that blended elements of online and face-to-face instruction with conditions taught entirely face-to-face. This research was conducted to highlight the impact of distance learning education system on education standard. The education standards were institutional support, course development, learning process, student support, faculty support, evaluation and assessment. A well developed questionnaire was administered and distributed among 26 faculty members of GCET, H-9 and Virtual University of Pakistan from each. Data was analyzed through correlation and regression analysis. Results confirmed that there is a significant relationship and impact of DLE system on education standards. This will also provide baseline for future research. It will add value to the existing body of knowledge.

Keywords: distance learning education, higher education, education standards, student performance

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Authors: Swapnil V. Pakhale, Sunil S. Bhagwat

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Three phase partitioning (TPP) an efficient bioseparation technique integrates the concentration and partial purification step of downstream processing of a biomolecule. Three Phase Partitioning is reported here for the first time for purification of Serratiopeptidase from fermentation broths of Serratia marcescens NRRL B-23112. The influence of various salts and solvents, Concentration of ammonium sulphate (20-60% w/v), Crude extract to t-butanol ratio (1:0.5-1:2.5) and system pH on Serratiopeptidase partitioning were investigated and optimum conditions for TPP were obtained in order to enhance the degree of purification and activity recovery of Serratiopeptidase. Under the optimal conditions of TPP, serratiopeptidase has been efficiently separated and concentrated with maximum recovery and degree of purification of 95.70% and 4.95 fold respectively. The present study shows TPP as an attractive downstream process for the purification of serratiopeptidase.

Keywords: three phase partitioning, serratiopeptidase, serratia marcescens NRRL B-23112, t-butanol, bioseparation

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Authors: Ruchi Jain, Chinnakonda S. Gopinath

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The CO oxidation is a primary reaction in heterogeneous catalysis due to its potential to overcome the air pollution caused by various reasons. Indeed, in the study of sustainable catalysis, the role played by water is very important. The present work is focused on studying the effect of moisture on the sustainability of Co3O4 NR catalyst for CO oxidation reaction at ambient temperature. The catalytic activity, electronic structure and the mechanistic aspects of spinel Co3O4 nanorod surfaces have been explored in dry and wet atmosphere by near-ambient pressure photoelectron spectroscopic techniques (NAP-PES) with conventional x-ray (Al kα) and ultraviolet sources (He-I).Comparative NAPPES studies have been employed to understand the elucidation of the catalytic reaction pathway and the evolution of various surface species. The presence of water with CO+O2 plummet the catalytic activity due to the change in electronic nature from predominantly oxidic (without water in the feed) to few intermediates covered Co3O4 surface. However, ≥ 375 K Co3O4 surface recovers and regain oxidation activity, at least partially, even in the presence of water. Above mentioned observations are fully supported by the changes observed in the work function of Co3O4 in the presence of wet (H2O+CO+O2) compared to dry (CO+O2) conditions. Various type of surface species, such as CO(ads), carbonate, formate, are found to be on the catalyst surface depending on the reaction conditions. Under dry condition, CO couples with labile O atoms to form CO2, however under wet conditions it also interacts with surface OH groups results in the formation carbonate and formate intermediate. The carbonate acts at reaction inhibitor at room temperature, however proves as active intermediate at temperature 375 K or above. On the other hand, formate has proved to be reaction spectator due to its high stability. The intrinsic role of these species to suppress the oxidation has been demonstrated through a possible reaction mechanism under different reaction conditions.

Keywords: heterogeneous catalysis, surface chemistry, photoelectron spectroscopy, ambient oxidation

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Authors: Jonathan A. Noble

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‘Origins’ is an exhibition designed and installed by MMA Design Studio, at the 2023 Venice Biennale. The instillation formed part of the ‘Dangerous Liaisons’ group exhibition at the Arsenale building. An immersive experience was created for those who visited, where video projection and the bodies of visitors interacted with the scene. Designed by South African architect, Mphethi Morojele – founder and owner of MMA – the primary inspiration for ‘Origins’ was the recent discovery by Professor Karim Sadr in 2019, of a substantial Tswana settlement. Situated in present day Suikerbosrand Nature Reserve, some 45km south of Johannesburg, this precolonial city named Kweneng, has been dated back to the fifteenth century. This remarkable discovery was achieved thanks to advanced aerial, LiDAR scanning technology, which was used to capture the traces of Kweneng, spanning a terrain of some 10km long and 2km wide. Discovered by light (LiDAR) and exhibited through light, Origins presents a simulated experience of Kweneng. The presentation of Kweneng was achieved primarily though video, with a circular projection onto the floor of an animated LiDAR data sequence, and onto the walls a filmed dance sequence choreographed to embody the architectural, spatial and symbolic significance of Kweneng. This paper documents the design process that was involved in the conceptualization, development and final realization of this noteworthy exhibition, with an elucidation upon key social and cultural questions pertaining to precolonial heritage, reimagined histories and postcolonial identity. Periods of change and of social awakening sometimes spark an interest in questions of origin, of cultural lineage and belonging – and which certainly is the case for contemporary, post-Apartheid South Africa. Researching this paper has required primary study of MMA Design Studio’s project archive, including various proposals and other design related documents, conceptual design sketches, architectural drawings and photographs. This material is supported by the authors first-hand interviews with Morejele and others who were involved, especially with respect to the choreography of the interpretive dance, LiDAR visualization techniques and video production that informed the simulated, immersive experience at the exhibition. Presenting a ‘dangerous liaison’ between architecture and dance, Origins looks into the distant past to frame contemporary questions pertaining to intangible heritage, animism and embodiment through architecture and dance – considerations which are required “to survive the future”, says Morojele.

Keywords: architecture and dance, Kweneng, MMA design studio, origins, Venice Biennale

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Authors: Parul Goel, Jyeshtharaj B. Joshi, Arun K. Nayak

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Nucleate boiling is characterized by the nucleation, growth and departure of the tiny individual vapor bubbles that originate in the cavities or imperfections present in the heating surface. It finds a wide range of applications, e.g. in heat exchangers or steam generators, core cooling in power reactors or rockets, cooling of electronic circuits, owing to its highly efficient transfer of large amount of heat flux over small temperature differences. Hence, it is important to be able to predict the rate of heat transfer and the safety limit heat flux (critical heat flux, heat flux higher than this can lead to damage of the heating surface) applicable for any given system. A large number of experimental and analytical works exist in the literature, and are based on the idea that the knowledge of the bubble dynamics on the microscopic scale can lead to the understanding of the full picture of the boiling heat transfer. However, the existing data in the literature are scattered over various sets of conditions and often in disagreement with each other. The correlations obtained from such data are also limited to the range of conditions they were established for and no single correlation is applicable over a wide range of parameters. More recently, a number of researchers have been trying to remove empiricism in the heat transfer models to arrive at more phenomenological models using extensive numerical simulations; these models require state-of-the-art experimental data for a wide range of conditions, first for input and later, for their validation. With this idea in mind, experiments with sub-cooled and saturated demineralized water have been carried out under atmospheric pressure to study the bubble dynamics- growth rate, departure size and frequencies for nucleate pool boiling. A number of heating elements have been used to study the dependence of vapor bubble dynamics on the heater surface finish and heater geometry along with the experimental conditions like the degree of sub-cooling, super heat and the heat flux. An attempt has been made to compare the data obtained with the existing data and the correlations in the literature to generate an exhaustive database for the pool boiling conditions.

Keywords: experiment, boiling, bubbles, bubble dynamics, pool boiling

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Authors: Amany Abdelrazek

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Fashion is considered the main feature of modern and postmodern capitalist and consumerist society. Consumer historians maintain that fashion, namely, a sector of people embracing a prevailing clothing style for a short period, started during the Middle Ages but gained popularity later. It symbolised the transition from a medieval society with its solid fixed religious values into a modern society with its secular consumer dynamic culture. Renaissance society was a modern secular society concerning its preoccupation with daily life and changing circumstances. Yet, the late 18th-century industrial revolution revolutionised thought and ideology in Europe. The Industrial Revolution reinforced the Western belief in rationality and strengthened the position of science. In such a rational Western society, modernity, with its new ideas, came to challenge the whole idea of old fixed norms, reflecting the modern secular, rational culture and renouncing the medieval pious consumer. In modern society, supported by the industrial revolution and mass production, fashion encouraged broader sectors of society to integrate into fashion reserved for the aristocracy and royal courts. Moreover, the fashion project emphasizes the human body and its beauty, contradicting Judeo-Christian culture, which tends to abhor and criticize interest in sensuality and hedonism. In mainstream Western discourse, fashionable dress differentiates between emancipated stylish consumerist secular modern female and the assumed oppressed traditional modest religious female. Opposing this discourse, I look at the controversy over what has been called "Islamic fashion" that started during the 1980s and continued to gain popularity in contemporary Egyptian society. I discuss the challenges of being a fashionable and Muslim practicing female in light of two prominent models for female "Islamic fashion" in postcolonial Egypt; Jasmin Mohshen, the first hijabi model in Egypt and Manal Rostom, the first Muslim woman to represent the Nike campaign in the Middle East. The research employs fashion and postcolonial theories to rethink current Muslim women's position on women's emancipation, Western modernity and practising faith in postcolonial Egypt. The paper argues that Muslim women's current innovative and fashionable dress can work as a counter-discourse to the Orientalist and exclusive representation of non-Western Muslim culture as an inherently inert timeless culture. Furthermore, "Islamic" fashionable dress as an aesthetic medium for expressing ideas and convictions in contemporary Egypt interrogates the claim of universal secular modernity and Western fashion theorists' reluctance to consider Islamic fashion as fashion.

Keywords: fashion, muslim women, modernity, secularism

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Authors: Mohsen Azarmjoo, Navid Sharifi, Zahra Alikhani Koopaei

Abstract:

This article aims to conserve energy and optimize the performance of solar water heaters using modern modeling systems. In this study, a large-scale solar water heater is modeled using an AVR microcontroller, which is a digital processor from the AVR microcontroller family. This mechatronic system will be used to analyze the performance and design of solar collectors, with the ultimate goal of improving the efficiency of the system being used. The findings of this research provide insights into optimizing the performance of solar water heaters. By manipulating the arrangement of solar panels and controlling the water flow through them using the AVR microcontroller, researchers can identify the optimal configurations and operational protocols to achieve the desired temperature and flow conditions. These findings can contribute to the development of more efficient and sustainable heating and cooling systems. This article investigates the optimization of solar water heater performance. It examines the impact of solar panel layout on system efficiency and explores methods of controlling water flow to achieve the desired temperature and flow conditions. The results of this research contribute to the development of more sustainable heating and cooling systems that rely on renewable energy sources.

Keywords: energy conservation, solar water heaters, solar cooling, simulation, mechatronics

Procedia PDF Downloads 73

Authors: Muthana A. M. Jamel Al-Gburi

Abstract:

Elimination of carbon dioxide (CO2) gas from our atmosphere is very important but complicated, and since there is always an increase in the gas amounts of the other greenhouse ones in our atmosphere, causes by both some of the human activities and the burning of the fossil fuels, which leads to the Global Warming phenomena i.e., increasing the earth temperature to a higher level, creates desertification, tornadoes and storms. In our present research project, we constructed our own system to extract carbon dioxide directly from the atmospheric air at the room conditions and investigated how to convert the gas into a useful mineral or Nano scale fibers made of carbon by using several chemical processes and chemical reactions leading to a valuable building material and also to mitigate the environmental negative change. In the present water pool system (Carbone Dioxide Domestic Extractor), the ocean-sea water was used to dissolve the CO2 gas from the room and converted into carbonate minerals by using a number of additives like shampoo, clay and MgO. Note that the atmospheric air includes CO2 gas has circulated within the sea water by air pump connected to a perforated tubes fixed deep on the pool base. Those chemical agents were mixed with the ocean-sea water to convert the formed acid from the water-CO2 reaction into a useful mineral. After we successfully constructed the system, we did intense experiments and investigations on the CO2 gas reduction level and found which is the optimum active chemical agent to work in the atmospheric conditions.

Keywords: global warming, CO₂ gas, ocean-sea water, additives, solubility level

Procedia PDF Downloads 76

Authors: H. Fraga, J. A. Santos

Abstract:

Vitiviniculture in Portugal is a key socio-economic sector, with a strong connection to local traditions and culture. Despite being a relatively small country, with prevailing Mediterranean environments, Portugal comprises an exceptionally large diversity of growth conditions (Terroirs). The vineyard area in Portugal is over 190 thousand hectares, being the eleventh wine producer and ninth wine exporter worldwide. Owing to the strong impact of weather and climate conditions on grapevine physiological development, grape berry quantity and quality show important inter-annual variability. Grapevines are also susceptible to climate change, as their responses will be unavoidably different under future climates. These impacts may change wine typicity of a given region or even its viticultural suitability. The current study reveals that the projected warming and drying trends for Portugal under the Representative Concentration Pathway (RCP) 4.5 and 8.5, are projected to 1) significantly shift current grapevine growing thermal conditions (e.g., heat and chill accumulation), 2) enhance water stress, 3) anticipate phenological timings and 4) modify yields. Moreover, the present study provides some hints regarding the effectiveness of mulching and irrigation as climate change adaptation measures. Our results show that the effectiveness of these adaptation measures will strongly rest on the strength of the climate change signal at a local scale, thus emphasizing the need for local-to-regional climate change assessments.

Keywords: viticulture, climate change, adaptation measures, Portugal

Procedia PDF Downloads 141

Authors: Daniyar Seitenov, Nazim Mir-Nasiri

Abstract:

Optimization of horizontal axis semi-exposed wind turbine has been performed using a shield protection that automatically protects the generator shaft at extreme wind speeds from over speeding, mechanical damage and continues generating electricity during the high wind speed conditions. A semi-exposed to wind generator has been designed and its structure has been described in this paper. The simplified point-force dynamic load model on the blades has been derived for normal and extreme wind conditions with and without shield involvement. Numerical simulation has been conducted at different values of wind speed to study the efficiency of shield application. The obtained results show that the maximum power generated by the wind turbine with shield does not exceed approximately the rated value of the generator, where shield serves as an automatic break for extreme wind speed values of 15 m/sec and above. Meantime the wind turbine without shield produced a power that is much larger than the rated value. The optimized horizontal axis semi-exposed wind turbine with shield protection is suitable for low and medium power generation when installed on the roofs of high rise buildings for harvesting wind energy. Wind shield works automatically with no power consumption. The structure of the generator with the protection, math simulation of kinematics and dynamics of power generation has been described in details in this paper.

Keywords: renewable energy, wind turbine, wind turbine optimization, high wind speed

Procedia PDF Downloads 176