Search results for: circular construction
673 Rheological Properties and Thermal Performance of Suspensions of Microcapsules Containing Phase Change Materials
Authors: Vinh Duy Cao, Carlos Salas-Bringas, Anna M. Szczotok, Marianne Hiorth, Anna-Lena Kjøniksen
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The increasing cost of energy supply for the purposes of heating and cooling creates a demand for more energy efficient buildings. Improved construction techniques and enhanced material technology can greatly reduce the energy consumption needed for the buildings. Microencapsulated phase change materials (MPCM) suspensions utilized as heat transfer fluids for energy storage and heat transfer applications provide promising potential solutions. A full understanding of the flow and thermal characteristics of microcapsule suspensions is needed to optimize the design of energy storage systems, in order to reduce the capital cost, system size, and energy consumption. The MPCM suspensions exhibited pseudoplastic and thixotropic behaviour, and significantly improved the thermal performance of the suspensions. Three different models were used to characterize the thixotropic behaviour of the MPCM suspensions: the second-order structural, kinetic model was found to give a better fit to the experimental data than the Weltman and Figoni-Shoemaker models. For all samples, the initial shear stress increased, and the breakdown rate accelerated significantly with increasing concentration. The thermal performance and rheological properties, especially the selection of rheological models, will be useful for developing the applications of microcapsules as heat transfer fluids in thermal energy storage system such as calculation of an optimum MPCM concentration, pumping power requirement, and specific power consumption. The effect of temperature on the shear thinning properties of the samples suggests that some of the phase change material is located outside the capsules, and contributes to agglomeration of the samples.Keywords: latent heat, microencapsulated phase change materials, pseudoplastic, suspension, thixotropic behaviour
Procedia PDF Downloads 261672 Chilean Business Orientalism: The Role of Non-State Actors in the Frame of Asymmetric Bilateral Relations
Authors: Pablo Ampuero, Claudia Labarca
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The current research paper assesses how the narrative of Chilean businesspeople about China shapes a new Orientalism Analyses on the role of non-state actors in foreign policy that have hitherto theorized about Orientalism as a narrative of hegemonic power. Hence, it has been instrumental to the efforts of imperialist powers to justify their mission civilisatrice. However, such conceptualization can seldom explain new complexities of international interactions at the height of globalization. Hence, we assessed the case of Chile, a small Latin American country, and its relationship with China, its largest trading partner. Through a discourse analysis of interviews with Chilean businesspeople engaged in the Chinese market, we could determine that Chile is building an Orientalist image of China. This new business Orientalism reinforces a relation of alterity based on commercial opportunities, traditional values, and natural dispositions. Hence, the perception of the Chinese Other amongst Chilean business people frames a new set of representations as part of the essentially commercial nature of current bilateral relations. It differs from previous frames, such as the racial bias frame of the early 20th century, or the anti-communist frame in reaction to Mao’s leadership. As in every narrative of alterity, there is not only a construction of the Other but also a definition of the Self. Consequently, this analysis constitutes a relevant case of the role of non-state actors in asymmetrical bilateral relations, where the non-state actors of the minor power build and act upon an Orientalist frame, which is not representative of its national status in the relation. This study emerges as a contribution on the relation amongst non-state actors in asymmetrical relations, where the smaller power’s business class acts on a negative prejudice of its interactions with its counterpart. The research builds upon the constructivist approach to international relations, linking the idea of Nation Branding with Orientalism in the case of Chile-China relations.Keywords: new business Orientalism, small power, framing, Chile-China relations
Procedia PDF Downloads 324671 Blue Economy and Marine Mining
Authors: Fani Sakellariadou
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The Blue Economy includes all marine-based and marine-related activities. They correspond to established, emerging as well as unborn ocean-based industries. Seabed mining is an emerging marine-based activity; its operations depend particularly on cutting-edge science and technology. The 21st century will face a crisis in resources as a consequence of the world’s population growth and the rising standard of living. The natural capital stored in the global ocean is decisive for it to provide a wide range of sustainable ecosystem services. Seabed mineral deposits were identified as having a high potential for critical elements and base metals. They have a crucial role in the fast evolution of green technologies. The major categories of marine mineral deposits are deep-sea deposits, including cobalt-rich ferromanganese crusts, polymetallic nodules, phosphorites, and deep-sea muds, as well as shallow-water deposits including marine placers. Seabed mining operations may take place within continental shelf areas of nation-states. In international waters, the International Seabed Authority (ISA) has entered into 15-year contracts for deep-seabed exploration with 21 contractors. These contracts are for polymetallic nodules (18 contracts), polymetallic sulfides (7 contracts), and cobalt-rich ferromanganese crusts (5 contracts). Exploration areas are located in the Clarion-Clipperton Zone, the Indian Ocean, the Mid Atlantic Ridge, the South Atlantic Ocean, and the Pacific Ocean. Potential environmental impacts of deep-sea mining include habitat alteration, sediment disturbance, plume discharge, toxic compounds release, light and noise generation, and air emissions. They could cause burial and smothering of benthic species, health problems for marine species, biodiversity loss, reduced photosynthetic mechanism, behavior change and masking acoustic communication for mammals and fish, heavy metals bioaccumulation up the food web, decrease of the content of dissolved oxygen, and climate change. An important concern related to deep-sea mining is our knowledge gap regarding deep-sea bio-communities. The ecological consequences that will be caused in the remote, unique, fragile, and little-understood deep-sea ecosystems and inhabitants are still largely unknown. The blue economy conceptualizes oceans as developing spaces supplying socio-economic benefits for current and future generations but also protecting, supporting, and restoring biodiversity and ecological productivity. In that sense, people should apply holistic management and make an assessment of marine mining impacts on ecosystem services, including the categories of provisioning, regulating, supporting, and cultural services. The variety in environmental parameters, the range in sea depth, the diversity in the characteristics of marine species, and the possible proximity to other existing maritime industries cause a span of marine mining impact the ability of ecosystems to support people and nature. In conclusion, the use of the untapped potential of the global ocean demands a liable and sustainable attitude. Moreover, there is a need to change our lifestyle and move beyond the philosophy of single-use. Living in a throw-away society based on a linear approach to resource consumption, humans are putting too much pressure on the natural environment. Applying modern, sustainable and eco-friendly approaches according to the principle of circular economy, a substantial amount of natural resource savings will be achieved. Acknowledgement: This work is part of the MAREE project, financially supported by the Division VI of IUPAC. This work has been partly supported by the University of Piraeus Research Center.Keywords: blue economy, deep-sea mining, ecosystem services, environmental impacts
Procedia PDF Downloads 77670 Modification of Hexagonal Boron Nitride Induced by Focused Laser Beam
Authors: I. Wlasny, Z. Klusek, A. Wysmolek
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Hexagonal boron nitride is a representative of a widely popular class of two-dimensional Van Der Waals materials. It finds its uses, among others, in construction of complexly layered heterostructures. Hexagonal boron nitride attracts great interest because of its properties characteristic for wide-gap semiconductors as well as an ultra-flat surface.Van Der Waals heterostructures composed of two-dimensional layered materials, such as transition metal dichalcogenides or graphene give hope for miniaturization of various electronic and optoelectronic elements. In our presentation, we will show the results of our investigations of the not previously reported modification of the hexagonal boron nitride layers with focused laser beam. The electrostatic force microscopy (EFM) images reveal that the irradiation leads to changes of the local electric fields for a wide range of laser wavelengths (from 442 to 785 nm). These changes are also accompanied by alterations of crystallographic structure of the material, as reflected by Raman spectra. They exhibit high stability and remain visible after at least five months. This behavior can be explained in terms of photoionization of the defect centers in h-BN which influence non-uniform electrostatic field screening by the photo-excited charge carriers. Analyzed changes influence local defect structure, and thus the interatomic distances within the lattice. These effects can be amplified by the piezoelectric character of hexagonal boron nitride, similar to that found in nitrides (e.g., GaN, AlN). Our results shed new light on the optical properties of the hexagonal boron nitride, in particular, those associated with electron-phonon coupling. Our study also opens new possibilities for h-BN applications in layered heterostructures where electrostatic fields can be used in tailoring of the local properties of the structures for use in micro- and nanoelectronics or field-controlled memory storage. This work is supported by National Science Centre project granted on the basis of the decision number DEC-2015/16/S/ST3/00451.Keywords: atomic force microscopy, hexagonal boron nitride, optical properties, raman spectroscopy
Procedia PDF Downloads 166669 Leaching of Metal Cations from Basic Oxygen Furnace (BOF) Steelmaking Slag Immersed in Water
Authors: Umashankar Morya, Somnath Basu
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Metalloids like arsenic are often present as contaminants in industrial effluents. Removal of the same is essential before the safe discharge of the wastewater into the environment. Otherwise, these pollutants tend to percolate into aquifers over a period of time and contaminate drinking water sources. Several adsorbents, including metal powders, carbon nanotubes and zeolites, are being used for this purpose, with varying degrees of success. However, most of these solutions are not only costly but also not always readily available. This restricts their use, especially among financially weaker communities. Slag generated globally from primary steelmaking operations exceeds 200 billion kg every year. Some of it is utilized for applications like road construction, filler in reinforced concrete, railway track ballast and recycled into iron ore agglomeration processes. However, these usually involve low-value addition, and a significant amount of the slag still ends up in a landfill. However, there is a strong possibility that the constituents in the steelmaking slag may immobilize metalloid contaminants present in wastewater through a combination of adsorption and precipitation of insoluble product(s). Preliminary experiments have already indicated that exposure to basic oxygen steelmaking slag does reduce pollutant concentration in wastewater. In addition, the slag is relatively inexpensive and available in large quantities and in several countries across the world. Investigations on the mechanism of interactions at the water-solid interfaces have been in progress for some time. However, at the same time, there are concerns about the possibility of leaching of metal ions from the slag particles in concentrations greater than what exists in the water bodies where the “treated” wastewater would eventually be discharged. The effect of such leached ions on the aquatic flora and fauna is yet uncertain. This has prompted the present investigation, which focuses on the leaching of metal ions from steelmaking slag particles in contact with wastewater, and the influence of these ions on the removal of contaminant species. Experiments were carried out to quantify the leaching behavior of different ionic species upon exposure of the slag particles to simulated wastewater, both with and without specific metalloid contaminants.Keywords: slag, water, metalloid, heavy metal, wastewater
Procedia PDF Downloads 71668 Construction of Genetic Recombinant Yeasts with High Environmental Tolerance by Accumulation of Trehalose and Detoxication of Aldehyde
Authors: Yun-Chin Chung, Nileema Divate, Gen-Hung Chen, Pei-Ru Huang, Rupesh Divate
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Many environmental factors, such as glucose concentration, ethanol, temperature, osmotic pressure and pH, decrease the production rate of ethanol using yeast as a starter. Fermentation starters with high tolerance to various stresses are always demanded for brewing industry. Trehalose, a storage carbohydrate in cell wall of yeast, plays an important role in tolerance of environmental stress by preserving integrity of plasma membrane and stabilizing proteins. Furan aldehydes are toxic to yeast and the growth rate of yeast is significantly reduced if furan aldehydes were present in the fermentation medium. In yeast, aldehyde reductase is involved in the detoxification of reactive aldehydes and consequently the growth of yeast is improved. The aims of this study were to construct a genetic recombinant Saccharomyces cerevisiae or Pichia pastoris with furfural and HMF degrading and high ethanol tolerance capacities. Yeast strains were engineered by genetic recombination for overexpression of trehalose-6-phosphate synthase gene (tps1) and aldehyde reductase gene (ari1). TPS1 gene was cloned from S. cerevisiae by reverse transcription-polymerase chain reaction (RT-PCR) and then ligated with pGAPZαC vector. The constructed vector, pGAPZC-tps1, was transformed to recombinant yeasts strain with overexpression of ari1. The transformants with pGAPZC-tps1-ari1 were generated called STA (S. cerevisiae) and PTA (P. pastoris) with overexpression of tps1, ari1. PCR with tps1-specific primers and western blot with his-tag confirmed the gene insertion and protein expression of tps1 in the transformants, respectively. The neutral trehalase gene (nth1) of STA was successfully deleted and the novel strain STAΔN will be used for further study, including the measurement of trehalose concentration and ethanol, furfural tolerance assay.Keywords: genetic recombinant, yeast, ethanol tolerance, trehalase, aldehyde reductase
Procedia PDF Downloads 414667 Scheduling Building Projects: The Chronographical Modeling Concept
Authors: Adel Francis
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Most of scheduling methods and software apply the critical path logic. This logic schedule activities, apply constraints between these activities and try to optimize and level the allocated resources. The extensive use of this logic produces a complex an erroneous network hard to present, follow and update. Planning and management building projects should tackle the coordination of works and the management of limited spaces, traffic, and supplies. Activities cannot be performed without the resources available and resources cannot be used beyond the capacity of workplaces. Otherwise, workspace congestion will negatively affect the flow of works. The objective of the space planning is to link the spatial and temporal aspects, promote efficient use of the site, define optimal site occupancy rates, and ensures suitable rotation of the workforce in the different spaces. The Chronographic scheduling modelling belongs to this category and models construction operations as well as their processes, logical constraints, association and organizational models, which help to better illustrate the schedule information using multiple flexible approaches. The model defined three categories of areas (punctual, surface and linear) and four different layers (space creation, systems, closing off space, finishing, and reduction of space). The Chronographical modelling is a more complete communication method, having the ability to alternate from one visual approach to another by manipulation of graphics via a set of parameters and their associated values. Each individual approach can help to schedule a certain project type or specialty. Visual communication can also be improved through layering, sheeting, juxtaposition, alterations, and permutations, allowing for groupings, hierarchies, and classification of project information. In this way, graphic representation becomes a living, transformable image, showing valuable information in a clear and comprehensible manner, simplifying the site management while simultaneously utilizing the visual space as efficiently as possible.Keywords: building projects, chronographic modelling, CPM, critical path, precedence diagram, scheduling
Procedia PDF Downloads 143666 A Study of the Interactions between the Inter-City Traffic System and the Spatial Structure Evolution in the Yangtze River Delta from Time and Space Dimensions
Authors: Zhang Cong, Cai Runlin, Jia Fengjiao
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The evolution of the urban agglomeration spatial structure requires strong support of the inter-city traffic system. And the inter-city traffic system can not only meet the demand of the urban agglomeration transportation but also guide the economic development. To correctly understand the relationship between inter-city traffic planning and urban agglomeration can help the urban agglomeration coordinated developing with the inter-city traffic system. The Yangtze River Delta is one of the most representative urban agglomerations in China with strong economic vitality, high city levels, diversified urban space form, and improved transport infrastructure. With the promotion of industrial division in the Yangtze River Delta and the regional travel facilitation brought by inter-city traffic, the urban agglomeration is characterized by highly increasing of inter-city transportation demand, the urbanization of regional traffic, adjacent regional transportation links breaking administrative boundaries, the networked channels and so on. Therefore, the development of inter-city traffic system presents new trends and challenges. This paper studies the interactions between inter-city traffic system and regional economic growth, regional factor flow, and regional spatial structure evolution in the Yangtze River Delta from two dimensions of time and space. On this basis, the adaptability of inter-city traffic development mode and urban agglomeration space structure is analyzed. First of all, the coordination between urban agglomeration planning and inter-city traffic planning is judged from the planning level. Secondly, the coordination between inter-city traffic elements and industries and population distributions is judged from the perspective of space. Finally, the coordination of the cross-regional planning and construction of inter-city traffic system is judged. The conclusions can provide an empirical reference for intercity traffic planning in Yangtze River Delta region and other urban agglomerations, and it is also of great significance to optimize the allocation of urban agglomerations and the overall operational efficiency.Keywords: evolution, interaction, inter-city traffic system, spatial structure
Procedia PDF Downloads 309665 Mapping and Database on Mass Movements along the Eastern Edge of the East African Rift in Burundi
Authors: L. Nahimana
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The eastern edge of the East African Rift in Burundi shows many mass movement phenomena corresponding to landslides, mudflow, debris flow, spectacular erosion (mega-gully), flash floods and alluvial deposits. These phenomena usually occur during the rainy season. Their extent and consecutive damages vary widely. To manage these phenomena, it is necessary to adopt a methodological approach of their mapping with a structured database. The elements for this database are: three-dimensional extent of the phenomenon, natural causes and conditions (geological lithology, slope, weathering depth and products, rainfall patterns, natural environment) and the anthropogenic factors corresponding to the various human activities. The extent of the area provides information about the possibilities and opportunities for mitigation technique. The lithological nature allows understanding the influence of the nature of the rock and its structure on the intensity of the weathering of rocks, as well as the geotechnical properties of the weathering products. The slope influences the land stability. The intensity of annual, monthly and daily rainfall helps to understand the conditions of water saturation of the terrains. Certain natural circumstances such as the presence of streams and rivers promote foot slope erosion and thus the occurrence and activity of mass movements. The construction of some infrastructures such as new roads and agglomerations deeply modify the flow of surface and underground water followed by mass movements. Using geospatial data selected on the East African Rift in Burundi, it is presented case of mass movements illustrating the nature, importance, various factors and the extent of the damages. An analysis of these elements for each hazard can guide the options for mitigation of the phenomenon and its consequences.Keywords: mass movement, landslide, mudflow, debris flow, spectacular erosion, mega-gully, flash flood, alluvial deposit, East African rift, Burundi
Procedia PDF Downloads 301664 Accepting the Illness and Moving toward Normality: Providing Continuous Care to a Patient by Utilizing Community Mental Health Nursing Skills
Authors: Szu-Yi Chang, Jiin-Ru Rong
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This paper discussed a case involving a young female patient with schizophrenia. The patient's condition was deteriorating, and she was becoming increasingly reliant on her family to take care of her, and as her father did not understand the illness well and was afraid that others will learn about the presence of a mentally ill individual in their family, he and the patient's mother were thus unable to cope with the patient's deteriorating condition, which in turn caused her to suffer from a lack of self-confidence and low self-esteem. The patient received nursing care from July 26th to October 25th, 2017, during which counseling, family visits, and phone interviews were carried out, and her condition was monitored. By referring to the practical ability indicators for community psychiatric mental health nursing that were developed by the psychiatric mental health nurses' association of the Republic of China, defining categories such as 'self-construction,' 'self-management,' 'disease management,' and 'family nursing,' and incorporating indicators for empowerment and various skills into the steps and strategies used for nursing care, we will able to help the patient to construct her own identity, raise her self-esteem, improve her ability to independently perform activities of daily living, strengthen her disease management ability, and gradually build up her life management skills. The patient's family was also encouraged to communicate more among themselves, so as to align them with the nursing care objectives of improving the patient's ability to adapt to community life and her disease. The results indicated that the patient was able to maintain her mental stability within her community. By implementing effective self-management and maintaining a routine life, the patient was able to continue her active participation in community work and rehabilitation activities. Improvements were also achieved with respect to family role issues by establishing mutual understanding among the patient's family members and gaining their support. It is recommended that mental health nurses can leverage their community mental health nursing skills and the related strategies to promote adaptation to community life among mental life patients.Keywords: community psychiatric mental health nursing, family nursing, schizophrenia, self-management
Procedia PDF Downloads 271663 Geospatial Assessments on Impacts of Land Use Changes and Climate Change in Nigeria Forest Ecosystems
Authors: Samuel O. Akande
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The human-induced climate change is likely to have severe consequences on forest ecosystems in Nigeria. Recent discussions and emphasis on issues concerning the environment justify the need for this research which examined deforestation monitoring in Oban Forest, Nigeria using Remote Sensing techniques. The Landsat images from TM (1986), ETM+ (2001) and OLI (2015) sensors were obtained from Landsat online archive and processed using Erdas Imagine 2014 and ArcGIS 10.3 to obtain the land use/land cover and Normalized Differential Vegetative Index (NDVI) values. Ground control points of deforested areas were collected for validation. It was observed that the forest cover decreased in area by about 689.14 km² between 1986 and 2015. The NDVI was used to determine the vegetation health of the forest and its implications on agricultural sustainability. The result showed that the total percentage of the healthy forest cover has reduced to about 45.9% from 1986 to 2015. The results obtained from analysed questionnaires shown that there was a positive correlation between the causes and effects of deforestation in the study area. The coefficient of determination value was calculated as R² ≥ 0.7, to ascertain the level of anthropogenic activities, such as fuelwood harvesting, intensive farming, and logging, urbanization, and engineering construction activities, responsible for deforestation in the study area. Similarly, temperature and rainfall data were obtained from Nigerian Meteorological Agency (NIMET) for the period of 1986 to 2015 in the study area. It was observed that there was a significant increase in temperature while rainfall decreased over the study area. Responses from the administered questionnaires also showed that futile destruction of forest ecosystem in Oban forest could be reduced to its barest minimum if fuelwood harvesting is disallowed. Thus, the projected impacts of climate change on Nigeria’s forest ecosystems and environmental stability is better imagined than experienced.Keywords: deforestation, ecosystems, normalized differential vegetative index, sustainability
Procedia PDF Downloads 189662 The Dressing Field Method of Gauge Symmetries Reduction: Presentation and Examples
Authors: Jeremy Attard, Jordan François, Serge Lazzarini, Thierry Masson
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Gauge theories are the natural background for describing geometrically fundamental interactions using principal and associated fiber bundles as dynamical entities. The central notion of these theories is their local gauge symmetry implemented by the local action of a Lie group H. There exist several methods used to reduce the symmetry of a gauge theory, like gauge fixing, bundle reduction theorem or spontaneous symmetry breaking mechanism (SSBM). This paper is a presentation of another method of gauge symmetry reduction, distinct from those three. Given a symmetry group H acting on a fiber bundle and its naturally associated fields (Ehresmann (or Cartan) connection, curvature, matter fields, etc.) there sometimes exists a way to erase (in whole or in part) the H-action by just reconfiguring these fields, i.e. by making a mere change of field variables in order to get new (‘composite‘) fields on which H (in whole or in part) does not act anymore. Two examples: the re-interpretation of the BEHGHK (Higgs) mechanism, on the one hand, and the top-down construction of Tractor and Penrose's Twistor spaces and connections in the framework of conformal Cartan geometry, one the other, will be discussed. They have, of course, nothing to do with each other but the dressing field method can be applied on both to get a new insight. In the first example, it turns out, indeed, that generation of masses in the Standard Model can be separated from the symmetry breaking, the latter being a mere change of field variables, i.e. a dressing. This offers an interpretation in opposition with the one usually found in textbooks. In the second case, the dressing field method applied to the conformal Cartan geometry offer a way of understanding the deep geometric nature of the so-called Tractors and Twistors. The dressing field method, distinct from a gauge transformation (even if it can have apparently the same form), is a systematic way of finding and erasing artificial symmetries of a theory, by a mere change of field variables which redistributes the degrees of freedom of the theories.Keywords: BEHGHK (Higgs) mechanism, conformal gravity, gauge theory, spontaneous symmetry breaking, symmetry reduction, twistors and tractors
Procedia PDF Downloads 230661 Nanostructured Oxide Layer by Anodization on Austenitic Stainless Steels: Structural and Corrosion Insights
Authors: Surya Prakash Gajagouni, Akram Alfantazi, Imad Barsoum
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Austenitic stainless steels are widely recognized for their exceptional corrosion resistance and mechanical properties, rendering them indispensable materials across various industries from construction to biomedical applications. However, in chloride and high temperature atmosphere it to further enhance their surface properties, anodization has emerged as a promising surface treatment technique. Anodization modifies the surface of stainless steels by creating a protective oxide layer, improving corrosion resistance and imparting additional functional characteristics. This paper explores the structural and corrosion characteristics of anodized austenitic stainless steels (AISI 304) using a two-step anodic technique. We utilized a perchloric acid-based electrolyte followed by an ammonium fluoride-based electrolyte. This sequential approach aimed to cultivate deeper and intricately self-ordered nanopore oxide arrays on a substrate made of 304 stainless steel. Electron Microscopic (SEM and TEM) images revealed nanoporous layered structures with increased length and crack development correlating with higher voltage and anodization time. Surface composition and chemical oxidation state of surface-treated SS were determined using X-ray photoelectron spectroscopy (XPS) techniques, revealing a surface layer rich in Ni and suppressed Cr, resulting in a thin film composed of Ni and Fe oxide compared to untreated SS. Electrochemical studies demonstrated enhanced corrosion resistance in a strong alkaline medium compared to untreated SS. Understanding the intricate relationship between the structural features of anodized stainless steels and their corrosion resistance is crucial for optimizing the performance of these materials in diverse applications. This study aims to contribute to the advancement of surface engineering strategies for enhancing the durability and functionality of austenitic stainless steels in aggressive environments.Keywords: austenitic stainless steel, anodization, nanoporous oxides, marine corrosion
Procedia PDF Downloads 30660 Co-Creating an International Flipped Faculty Development Model: A US-Afghan Case Study
Authors: G. Alex Ambrose, Melissa Paulsen, Abrar Fitwi, Masud Akbari
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In 2016, a U.S. business college was awarded a sub grant to work with FHI360, a nonprofit human development organization, to support a university in Afghanistan funded by the State Department’s U.S. Agency for International Development (USAID). A newly designed Master’s Degree in Finance and Accounting is being implemented to support Afghanistan’s goal of 20% females in higher education and industry by 2020 and to use finance and accounting international standards to attract capital investment for economic development. This paper will present a case study to describe the co-construction of an approach to an International Flipped Faculty Development Model grounded in blended learning theory. Like education in general, faculty development is also evolving from the traditional face to face environment and interactions to the fully online and now to a best of both blends. Flipped faculty development is both a means and a model for careful integration of the strengths of the synchronous and asynchronous dynamics and technologies with the combination of intentional sequencing to pre-online interactions that prepares and enhances the face to face faculty development and mentorship residencies with follow-up post-online support. Initial benefits from this model include giving the Afghan faculty an opportunity to experience and apply modern teaching and learning strategies with technology in their own classroom. Furthermore, beyond the technological and pedagogical affordances, the reciprocal benefits gained from the mentor-mentee, face-to-face relationship will be explored. Evidence to support this model includes: empirical findings from pre- and post-Faculty Mentor/ Mentee survey results, Faculty Mentorship group debriefs, Faculty Mentorship contact logs, and student early/end of semester feedback. In addition to presenting and evaluating this model, practical challenges and recommendations for replicating international flipped faculty development partnerships will be provided.Keywords: educational development, faculty development, international development, flipped learning
Procedia PDF Downloads 181659 A Review on Investigating the Relations between Water Harvesting and Water Conflicts
Authors: B. Laurita
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The importance of Water Harvesting (WH) as an effective mean to deal with water scarcity is universally recognized. The collection and storage of rainwater, floodwater or quick runoff and their conversion to productive uses can ensure water availability for domestic and agricultural use, enabling a lower exploitation of the aquifer, preventing erosion events and providing significant ecosystem services. At the same time, it has been proven that it can reduce the insurgence of water conflicts if supported by a cooperative process of planning and management. On the other hand, the construction of water harvesting structures changes the hydrological regime, affecting upstream-downstream dynamics and changing water allocation, often causing contentions. Furthermore, dynamics existing between water harvesting and water conflict are not properly investigated yet. Thus, objective of this study is to analyze the relations between water harvesting and the insurgence of water conflicts, providing a solid theoretical basis and foundations for future studies. Two search engines were selected in order to perform the study: Google Scholar and Scopus. Separate researches were conducted on the mutual influences between water conflicts and the four main water harvesting techniques: rooftop harvesting, surface harvesting, underground harvesting, runoff harvesting. Some of the aforementioned water harvesting techniques have been developed and implemented on scales ranging from the small, household-sided ones, to gargantuan dam systems. Instead of focusing on the collisions related to large-scale systems, this review is aimed to look for and collect examples of the effects that the implementation of small water harvesting systems has had on the access to the water resource and on water governance. The present research allowed to highlight that in the studies that have been conducted up to now, water harvesting, and in particular those structures that allow the collection and storage of water for domestic use, is usually recognized as a positive, palliative element during contentions. On the other hand, water harvesting can worsen and, in some cases, even generate conflicts for water management. This shows the necessity of studies that consider both benefits and negative influences of water harvesting, analyzing its role respectively as triggering or as mitigating factor of conflicting situations.Keywords: arid areas, governance, water conflicts, water harvesting
Procedia PDF Downloads 200658 Evaluation of Stress Relief using Ultrasonic Peening in GTAW Welding and Stress Corrosion Cracking (SCC) in Stainless Steel, and Comparison with the Thermal Method
Authors: Hamidreza Mansouri
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In the construction industry, the lifespan of a metal structure is directly related to the quality of welding. In most metal structures, the welded area is considered critical and is one of the most important factors in design. To date, many fracture incidents caused by these types of cracks have occurred. Various methods exist to increase the lifespan of welds to prevent failure in the welded area. Among these methods, the application of ultrasonic peening, in addition to the stress relief process, can manually and more precisely adjust the geometry of the weld toe and prevent stress concentration in this part. This research examined Gas Tungsten Arc Welding (GTAW) on common structural steels and 316 stainless steel, which require precise welding, to predict the optimal condition. The GTAW method was used to create residual stress; two samples underwent ultrasonic stress relief, and for comparison, two samples underwent thermal stress relief. Also, no treatment was considered for two samples. The residual stress of all six pieces was measured by X-Ray Diffraction (XRD) method. Then, the two ultrasonically stress-relieved samples and two untreated samples were exposed to a corrosive environment to initiate cracking and determine the effectiveness of the ultrasonic stress relief method. Thus, the residual stress caused by GTAW in the samples decreased by 3.42% with thermal treatment and by 7.69% with ultrasonic peening. Furthermore, the results show that the untreated sample developed cracks after 740 hours, while the ultrasonically stress-relieved piece showed no cracks. Given the high costs of welding and post-welding zone modification processes, finding an economical, effective, and comprehensive method that has the least limitations alongside a broad spectrum of usage is of great importance. Therefore, the impact of various ultrasonic peening stress relief parameters and the selection of the best stress relief parameter to achieve the longest lifespan for the weld area is highly significant.Keywords: GTAW welding, stress corrosion cracking(SCC), thermal method, ultrasonic peening.
Procedia PDF Downloads 40657 A Meta-Analysis towards an Integrated Framework for Sustainable Urban Transportation within the Concept of Sustainable Cities
Authors: Hande Aladağ, Gökçe Aydın
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The world’s population is increasing continuously and rapidly. Moreover, there are other problems such as the decline of natural energy resources, global warming, and environmental pollution. These facts have made sustainability an important and primary topic from future planning perspective. From this perspective, constituting sustainable cities and communities can be considered as one of the key issues in terms of sustainable development goals. The concept of sustainable cities can be evaluated under three headings such as green/sustainable buildings, self – contained cities and sustainable transportation. This study only concentrates on how to form and support a sustainable urban transportation system to contribute to the sustainable urbanization. Urban transportation system inevitably requires many engineering projects with various sizes. Engineering projects generally have four phases, in the following order: Planning, design, construction, operation. The order is valid but there are feedbacks from every phase to every phase in its upstream. In this regard, engineering projects are iterative processes. Sustainability is an integrated and comprehensive concept thus it should be among the primary concerns in every phase of transportation projects. In the study, a meta-analysis will be performed on the related studies in the literature. It is targeted and planned that, as a result of the findings of this meta-analysis, a framework for the list of principles and actions for sustainable transport will be formed. The meta-analysis will be performed to point out and clarify sustainability approaches in every phase of the related engineering projects, with also paying attention to the iterative nature of the process and relative contribution of the action for the outcomes of the sustainable transportation system. However, the analysis will not be limited to the engineering projects, non-engineering solutions will also be included in the meta-analysis. The most important contribution of this study is a determination of the outcomes of a sustainable urban transportation system in terms of energy efficiency, resource preservation and related social, environmental and economic factors. The study is also important because it will give light to the engineering and management approaches to achieve these outcomes.Keywords: meta-analysis, sustainability, sustainable cities, sustainable urban transportation, urban transportation
Procedia PDF Downloads 322656 Comparative Public Administration: A Case Study of ASEAN Member States
Authors: Nattapol Pourprasert
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This research is to study qualitative research having two objectives: 1. to study comparison of private sector of government to compare with ASEAN Member States, 2. to study trend of private enterprise administration of ASEAN Member States. The results are: (1) Thai people focus on personal resource administrative system, (2) Indonesia focuses on official system by good administrative principles, (3) Malaysia focuses on technology development to service people, (4) Philippines focuses on operation system development, (5) Singapore focuses on public service development, (6) Brunei Darussalam focuses on equality in government service of people, (7) Vietnam focuses on creating government labor base and develop testing and administration of operation test, (8) Myanmar focuses on human resources development, (9) Laos focuses on form of local administration, (10) Cambodia focuses on policy revolution in personal resources. The result of the second part of the study are: (1) Thailand created government personnel to be power under qualitative official structural event, (2) Indonesia has Bureaucracy Reform Roadmap of Bureaucracy Reform and National Development Plan Medium Term, (3) Malaysia has database for people service, (4) Philippines follows up control of units operation by government policy, (5) Singapore created reliability, participation of people to set government policy people’s demand, (6) Brunei Darussalam has social welfare to people, (7) Vietnam revolved testing system and administration including manpower base construction of government effectively, (8) Myanmar creates high rank administrators to develop country, (9) Laos distributes power to locality, and (10) Cambodia revolved personnel resource policy.Keywords: public administration development, ASEAN member states, private sector, government
Procedia PDF Downloads 246655 Approaches to Reduce the Complexity of Mathematical Models for the Operational Optimization of Large-Scale Virtual Power Plants in Public Energy Supply
Authors: Thomas Weber, Nina Strobel, Thomas Kohne, Eberhard Abele
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In context of the energy transition in Germany, the importance of so-called virtual power plants in the energy supply continues to increase. The progressive dismantling of the large power plants and the ongoing construction of many new decentralized plants result in great potential for optimization through synergies between the individual plants. These potentials can be exploited by mathematical optimization algorithms to calculate the optimal application planning of decentralized power and heat generators and storage systems. This also includes linear or linear mixed integer optimization. In this paper, procedures for reducing the number of decision variables to be calculated are explained and validated. On the one hand, this includes combining n similar installation types into one aggregated unit. This aggregated unit is described by the same constraints and target function terms as a single plant. This reduces the number of decision variables per time step and the complexity of the problem to be solved by a factor of n. The exact operating mode of the individual plants can then be calculated in a second optimization in such a way that the output of the individual plants corresponds to the calculated output of the aggregated unit. Another way to reduce the number of decision variables in an optimization problem is to reduce the number of time steps to be calculated. This is useful if a high temporal resolution is not necessary for all time steps. For example, the volatility or the forecast quality of environmental parameters may justify a high or low temporal resolution of the optimization. Both approaches are examined for the resulting calculation time as well as for optimality. Several optimization models for virtual power plants (combined heat and power plants, heat storage, power storage, gas turbine) with different numbers of plants are used as a reference for the investigation of both processes with regard to calculation duration and optimality.Keywords: CHP, Energy 4.0, energy storage, MILP, optimization, virtual power plant
Procedia PDF Downloads 169654 Influence of Climate Change on Landslides in Northeast India: A Case Study
Authors: G. Vishnu, T. V. Bharat
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Rainfall plays a major role in the stability of natural slopes in tropical and subtropical regions. These slopes usually have high slope angles and are stable during the dry season. The critical rainfall intensity that might trigger a landslide may not be the highest rainfall. In addition to geological discontinuities and anthropogenic factors, water content, suction, and hydraulic conductivity also play a role. A thorough geotechnical investigation with the principles of unsaturated soil mechanics is required to predict the failures in these cases. The study discusses three landslide events that had occurred in residual hills of Guwahati, India. Rainfall data analysis, history image analysis, land use, and slope maps of the region were analyzed and discussed. The landslide occurred on June (24, 26, and 28) 2020, on the respective sites, but the highest rainfall was on June (6 and 17) 2020. The factors that lead to the landslide occurrence is the combination of critical events initiated with rainfall, causing a reduction in suction. The sites consist of a mixture of rocks and soil. The slope failure occurs due to the saturation of the soil layer leading to loss of soil strength resulting in the flow of the entire soil rock mass. The land-use change, construction activities, other human and natural activities that lead to faster disintegration of rock mass may accelerate the landslide events. Landslides in these slopes are inevitable, and the development of an early warning system (EWS) to save human lives and resources is a feasible way. The actual time of failure of a slope can be better predicted by considering all these factors rather than depending solely on the rainfall intensities. An effective EWS is required with less false alarms in these regions by proper instrumentation of slope and appropriate climatic downscaling.Keywords: early warning system, historic image analysis, slope instrumentation, unsaturated soil mechanics
Procedia PDF Downloads 110653 The Creation of Micromedia on Social Networking Sites as a Social Movement Strategy: The Case of Migration Aid, a Hungarian Refugee Relief Group
Authors: Zsofia Nagy, Tibor Dessewffy
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The relationship between social movements and the media that represents them comprises both of the media representation of movements on the one hand, and the media strategies employed by movements on the other. A third possible approach is to connect the two and look at the interactions connecting the two sides. This relationship has been affected by the emergence of social networking sites (SNS) that have a transformative effect on both actors. However, the extent and direction of these changes needs to be investigated. Empirical case studies that focus on newly enabled forms of social movements can contribute to these debates in an analytically fruitful way. Therefore in our study, we use the case of Migration Aid, a Hungarian Facebook-based grassroots relief organization that gained prominence during the refugee crisis that unfolded in Hungary in 2015. Migration Aid formed without the use of traditional mobilizational agents, and that took over roles traditionally occupied by formal NGOs or the state. Analyzing different movement strategies towards the media - we find evidence that while effectively combining these strategies, SNSs also create affordances for movements to shift their strategy towards creating alternatives, their own micromedia. Beyond the practical significance of this – the ability to disseminate alternative information independently from traditional media – it also allowed the group to frame the issue in their own terms and to replace vertical modes of communication with horizontal ones. The creation of micromedia also shifts the relationship between social movements and the media away from an asymmetrical and towards a more symbiotic co-existence. We provide four central factors – project identity, the mobilization potential of SNSs, the disruptiveness of the event and selectivity in the construction of social knowledge – that explain this shift. Finally, we look at the specific processes that contribute to the creation of the movement’s own micromedia. We posit that these processes were made possible by the rhizomatic structure of the group and a function of SNSs we coin the Social Information Thermostat function. We conclude our study by positioning our findings in relation with the broader context.Keywords: social networking sites, social movements, micromedia, media strategies
Procedia PDF Downloads 258652 Research on the Impact of Spatial Layout Design on College Students’ Learning and Mental Health: Analysis Based on a Smart Classroom Renovation Project in Shanghai, China
Authors: Zhang Dongqing
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Concern for students' mental health and the application of intelligent advanced technologies are driving changes in teaching models. The traditional teacher-centered classroom is beginning to transform into a student-centered smart interactive learning environment. Nowadays, smart classrooms are compatible with constructivist learning. This theory emphasizes the role of teachers in the teaching process as helpers and facilitators of knowledge construction, and students learn by interacting with them. The spatial design of classrooms is closely related to the teaching model and should also be developed in the direction of smart classroom design. The goal is to explore the impact of smart classroom layout on student-centered teaching environment and teacher-student interaction under the guidance of constructivist learning theory, by combining the design process and feedback analysis of the smart transformation project on the campus of Tongji University in Shanghai. During the research process, the theoretical basis of constructivist learning was consolidated through literature research and case analysis. The integration and visual field analysis of the traditional and transformed indoor floor plans were conducted using space syntax tools. Finally, questionnaire surveys and interviews were used to collect data. The main conclusions are as followed: flexible spatial layouts can promote students' learning effects and mental health; the interactivity of smart classroom layouts is different and needs to be combined with different teaching models; the public areas of teaching buildings can also improve the interactive learning atmosphere by adding discussion space. This article provides a data-based research basis for improving students' learning effects and mental health, and provides a reference for future smart classroom design.Keywords: spatial layout, smart classroom, space syntax, renovation, educational environment
Procedia PDF Downloads 65651 Landfill Site Selection Using Multi-Criteria Decision Analysis A Case Study for Gulshan-e-Iqbal Town, Karachi
Authors: Javeria Arain, Saad Malik
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The management of solid waste is a crucial and essential aspect of urban environmental management especially in a city with an ever increasing population such as Karachi. The total amount of municipal solid waste generated from Gulshan e Iqbal town on average is 444.48 tons per day and landfill sites are a widely accepted solution for final disposal of this waste. However, an improperly selected site can have immense environmental, economical and ecological impacts. To select an appropriate landfill site a number of factors should be kept into consideration to minimize the potential hazards of solid waste. The purpose of this research is to analyse the study area for the construction of an appropriate landfill site for disposal of municipal solid waste generated from Gulshan e-Iqbal Town by using geospatial techniques considering hydrological, geological, social and geomorphological factors. This was achieved using analytical hierarchy process and fuzzy analysis as a decision support tool with integration of geographic information sciences techniques. Eight most critical parameters, relevant to the study area, were selected. After generation of thematic layers for each parameter, overlay analysis was performed in ArcGIS 10.0 software. The results produced by both methods were then compared with each other and the final suitability map using AHP shows that 19% of the total area is Least Suitable, 6% is Suitable but avoided, 46% is Moderately Suitable, 26% is Suitable, 2% is Most Suitable and 1% is Restricted. In comparison the output map of fuzzy set theory is not in crisp logic rather it provides an output map with a range of 0-1, where 0 indicates least suitable and 1 indicates most suitable site. Considering the results it is deduced that the northern part of the city is appropriate for constructing the landfill site though a final decision for an optimal site could be made after field survey and considering economical and political factors.Keywords: Analytical Hierarchy Process (AHP), fuzzy set theory, Geographic Information Sciences (GIS), Multi-Criteria Decision Analysis (MCDA)
Procedia PDF Downloads 498650 Accessing Properties of Alkali Activated Ground Granulated Blast Furnace Slag Based Self Compacting Geopolymer Concrete Incorporating Nano Silica
Authors: Guneet Saini, Uthej Vattipalli
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In a world with increased demand for sustainable construction, waste product of one industry could be a boon to the other in reducing the carbon footprint. Usage of industrial waste such as fly ash and ground granulated blast furnace slag have become the epicenter of curbing the use of cement, one of the major contributors of greenhouse gases. In this paper, empirical studies have been done to develop alkali activated self-compacting geopolymer concrete (GPC) using ground granulated blast furnace slag (GGBS), incorporated with 2% nano-silica by weight, through evaluation of its fresh and hardening properties. Experimental investigation on 6 mix designs of varying molarity of 10M, 12M and 16M of the alkaline solution and a binder content of 450 kg/m³ and 500 kg/m³ has been done and juxtaposed with GPC mix design composed of 16M alkaline solution concentration and 500 kg/m³ binder content without nano-silica. The sodium silicate to sodium hydroxide ratio (SS/SH), alkaline activator liquid to binder ratio (AAL/B) and water to binder ratio (W/B), which significantly affect the performance and mechanical properties of GPC, were fixed at 2.5, 0.45 and 0.4 respectively. To catalyze the early stage geopolymerisation, oven curing is done maintaining the temperature at 60˚C. This paper also elucidates the test results for fresh self-compacting concrete (SCC) done as per EFNARC guidelines. The mechanical properties tests conducted were: compressive strength test after 7 days, 28 days, 56 days and 90 days; flexure test; split tensile strength test after 28 days, 56 days and 90 days; X-ray diffraction test to analyze the mechanical performance and sorptivity test for testing of permeability. The study revealed that the sample of 16M concentration of alkaline solution with 500 Kg/m³ binder content containing 2% nano silica produced the highest compressive, flexural and split tensile strength of 81.33 MPa, 7.875 MPa, and 6.398 MPa respectively, at the end of 90 days.Keywords: alkaline activator liquid, geopolymer concrete, ground granulated blast furnace slag, nano silica, self compacting
Procedia PDF Downloads 138649 Promising Anti-Displacement Practices for High Cost Cities
Authors: Leslie M. Mullins
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In the face of dramatically shifting demographic trends and macroeconomic pressures on affordable housing in high-cost cities, municipalities and developers have been forced to develop new models of sustainable development that integrates elements of substantial rehabilitation and new construction while controlling for relocation and mass displacement. Community development partners in the San Francisco Bay Area of Northern California are starting to prioritize anti-displacement strategies when rehabilitating severely neglected public housing developments. This study explored the community-driven efforts to transform four dilapidated public housing sites (N=2,600 households) into thriving mixed-income housing communities. Eight interviews were conducted with frontline workers (property managers and service providers), who directly worked with residents throughout critical stages of the relocation and leasing process. Interviews were audio-recorded, transcribed, and analyzed by a systematic procedure for qualitative analysis to identify key themes on the topics of interest. Also, an extensive literature analysis was conducted to determine promising practices throughout the industry. This study highlighted that resident’s emotional attachment to their homes (regardless of the deteriorating conditions of their unit) could both a) impede the relocation process and substantially impact the budget and timeline, while b) simultaneously providing a basis for an enhanced sense of belonging and community cohesion. This phenomenon often includes the welcoming of new residents and cultures. Resident centered workshops, healing centered rituals, and extensive 'hands-on' guidance was highlighted as promising practices that resulted in residential retention rates that were two to three times the national average and positively impacted the overall project’s budget and timeline.Keywords: anti-displacement strategies, community based practices, community cohesion, cultural preservation, healing-centered, public housing, relocation, trauma-informed
Procedia PDF Downloads 127648 Creating a Professional Teacher Identity in Britain via Accent Modification
Authors: Alex Baratta
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In Britain, accent is arguably still a sensitive issue, and for broad regional accents in particular, the connotations can often be quite negative. Within primary and secondary teaching, what might the implications be for teachers with such accents? To investigate this, the study collected the views of 32 British trainee teachers via semi-structured interviews, and questionnaires, to understand how their accent plays a role in the construction of a professional identity. From the results, it is clear that for teachers from the North and Midlands, in particular, accent modification is something that is required by their mentors; for teachers from the Home Counties, accent is rarely mentioned. While the mentors’ rationale for accent modification is to ensure teachers are better understood and/or to sound ‘professional’, many teachers feel that it is a matter of linguistic prejudice and therefore regard an accent modified for someone else as leading to a fraudulent identity. Moreover, some of the comments can be quite blunt, such as the Midlands teacher who resides in the South being told that it was ‘best to go back to where you come from’ if she couldn’t modify her accent to Southern pronunciation. From the results, there are three broad phonological changes expected: i) Northern/Midlands-accented teachers need to change to Southern pronunciation in words such as bath and bus; thus, a change from [baθ] [bʊs] to [bɑ:θ] [bʌs], ii) Teachers from the North, notably Yorkshire, told to change from monophthongs to diphthongs; thus, a change from [go:] to [goʊ], iii) Glottal stops are to be avoided; a teacher from South London was told by her mentor to write the word ‘water’ with a capital t (waTer), in order to avoid her use of a glottal stop. Thus, in a climate of respect for diversity and equality, this study is timely for the following reasons. First, it addresses an area for which equality is not necessarily relevant – that of accent in British teaching. Second, while many British people arguably have an instinct for ‘broad’ versus more ‘general’ versions of regional accents, there appear to be no studies which have attempted to explain what this means from a purely phonological perspective. Finally, given that the Teachers’ Standards do not mention accent as part of the desired linguistic standards, this study hopes to start a national debate as to whether or not they should, rather than shy away from what can be a potentially complex – and sensitive – topic.Keywords: accent, accommodation, identity, teaching
Procedia PDF Downloads 141647 Europe's War on Refugees: The Increased Need for International Protection and Promotion of Migrant Rights
Authors: Rai Friedman
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The recent migrant crisis has revealed an unmet demand for increased international protection and promotion of migrant rights. Europe has found itself at the centre of the migration crisis, being the recipient to the largest number of asylum-seekers since the conclusion of the second World War. Rather than impart a unified humanitarian lens of offering legal protections, the Schengen territory is devising new, preventative measures to confront the influx of asylum-seekers. This paper will focus on the refugee crisis in Europe as it relates to the Central Mediterranean route. To do so, it will outline the increased need for international protection for migrant rights through analyzing historic human rights treaties and conventions; the formation of the current composition of the Schengen area; the evolutionary changes in policies and legal landscapes throughout Europe and the Central Mediterranean route; the vernacular transformation surrounding refugees, migrants, and asylum-seekers; and expose the gaps in international protection. It will also discuss Europe’s critical position, both geographically and conceptually, critiquing the notion of European victimization. Lastly, it will discuss the increased harm of preventative border measures and argue for tangible sustainability solutions through economic programming models in highly vulnerable countries. To do so, this paper will observe a case study in Algeria that has conceded to an economic programming model for forced migrants. In 2017 amid worker shortages, Algeria announced it would grant African migrants’ legal status to become agriculturalists and construction workers. Algeria is one of the few countries along the Central Mediterranean route that has adopted a law to govern foreign nationals’ conditions of entry, stay and circulation. Thereafter, it will provide recommendations for solutions for forced migration along the Central Mediterranean route and advocate for strengthened protections under international law.Keywords: refugees, migrants, human rights, middle east, Africa, mediterranean, international humanitarian law, policy
Procedia PDF Downloads 103646 Analysis of the Occurrence of Hydraulic Fracture Phenomena in Roudbar Lorestan Dam
Authors: Masoud Ghaemi, MohammadJafar Hedayati, Faezeh Yousefzadeh, Hoseinali Heydarzadeh
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According to the statistics of the International Committee on Large Dams, internal erosion and piping (scour) are major causes of the destruction of earth-fill dams. If such dams are constructed in narrow valleys, the valley walls will increase the arching of the dam body due to the transfer of vertical and horizontal stresses, so the occurrence of hydraulic fracturing in these embankments is more likely. Roudbar Dam in Lorestan is a clay-core pebble earth-fill dam constructed in a relatively narrow valley in western Iran. Three years after the onset of impoundment, there has been a fall in dam behavior. Evaluation of the dam behavior based on the data recorded on the instruments installed inside the dam body and foundation confirms the occurrence of internal erosion in the lower and adjacent parts of the core on the left support (abutment). The phenomenon of hydraulic fracturing is one of the main causes of the onset of internal erosion in this dam. Accordingly, the main objective of this paper is to evaluate the validity of this hypothesis. To evaluate the validity of this hypothesis, the dam behavior during construction and impoundment has been first simulated with a three-dimensional numerical model. Then, using validated empirical equations, the safety factor of the occurrence of hydraulic fracturing phenomenon upstream of the dam score was calculated. Then, using the artificial neural network, the failure time of the given section was predicted based on the maximum stress trend created. The study results show that steep slopes of valley walls, sudden changes in coefficient, and differences in compressibility properties of dam body materials have caused considerable stress transfer from core to adjacent valley walls, especially at its lower levels. This has resulted in the coefficient of confidence of the occurrence of hydraulic fracturing in each of these areas being close to one in each of the empirical equations used.Keywords: arching, artificial neural network, FLAC3D, hydraulic fracturing, internal erosion, pore water pressure
Procedia PDF Downloads 173645 Influence of Driving Speed on Bearing Capacity Measurement of Intra-Urban Roads with the Traffic Speed Deflectometer(Tsd)
Authors: Pahirangan Sivapatham, Barbara Esser, Andreas Grimmel
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In times of limited public funds and, in particular, an increased social, environmental awareness, as well as the limited availability of construction materials, sustainable and resource-saving pavement management system, is becoming more and more important. Therefore, the knowledge about the condition of the structural substances, particularly bearing capacity and its consideration while planning the maintenance measures of the subordinate network, i.e., state and municipal roads unavoidable. According to the experience, the recommended ride speed of the Traffic Speed Deflectometer (TSD) shall be higher than 40 km/h. Holding of this speed on the intra-urban roads is nearly not possible because of intersections and traffic lights as well as the speed limit. A sufficient background of experience for the evaluation of bearing capacity measurements with TSD in the range of lower speeds is not available yet. The aim of this study is to determine the possible lowest ride speed of the TSD while the bearing capacity measurement on the intra-urban roads. The manufacturer of the TSD used in this study states that the measurements can be conducted at a ride speed of higher than 5 km/h. It is well known that with decreasing ride speed, the viscous fractions in the response of the asphalt pavement increase. This must be taken into account when evaluating the bearing capacity data. In the scope of this study, several measurements were carried out at different speeds between 10 km/h and 60 km/h on the selected intra-urban roads with Pavement-Scanner of the University of Wuppertal, which is equipped with TSD. Pavement-Scanner is able to continuously determine the deflections of asphalt roads in flowing traffic at speeds of up to 80 km/h. The raw data is then aggregated to 10 m mean values so that, as a rule, a bearing capacity characteristic value can be determined for each 10 m road section. By means of analysing of obtained test results, the quality and validity of the determined data rate subject to the riding speed of TSD have been determined. Moreover, the data and pictures of the additional measuring systems of Pavement-Scanners such as High-Speed Road Monitor, Ground Penetration Radar and front cameras can be used to determine and eliminate irregularities in the pavement, which could influence the bearing capacity.Keywords: bearing capacity measurement, traffic speed deflectometer, inter-urban roads, Pavement-Scanner, structural substance
Procedia PDF Downloads 228644 Bounded Rational Heterogeneous Agents in Artificial Stock Markets: Literature Review and Research Direction
Authors: Talal Alsulaiman, Khaldoun Khashanah
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In this paper, we provided a literature survey on the artificial stock problem (ASM). The paper began by exploring the complexity of the stock market and the needs for ASM. ASM aims to investigate the link between individual behaviors (micro level) and financial market dynamics (macro level). The variety of patterns at the macro level is a function of the AFM complexity. The financial market system is a complex system where the relationship between the micro and macro level cannot be captured analytically. Computational approaches, such as simulation, are expected to comprehend this connection. Agent-based simulation is a simulation technique commonly used to build AFMs. The paper proceeds by discussing the components of the ASM. We consider the roles of behavioral finance (BF) alongside the traditionally risk-averse assumption in the construction of agent's attributes. Also, the influence of social networks in the developing of agents’ interactions is addressed. Network topologies such as a small world, distance-based, and scale-free networks may be utilized to outline economic collaborations. In addition, the primary methods for developing agents learning and adaptive abilities have been summarized. These incorporated approach such as Genetic Algorithm, Genetic Programming, Artificial neural network and Reinforcement Learning. In addition, the most common statistical properties (the stylized facts) of stock that are used for calibration and validation of ASM are discussed. Besides, we have reviewed the major related previous studies and categorize the utilized approaches as a part of these studies. Finally, research directions and potential research questions are argued. The research directions of ASM may focus on the macro level by analyzing the market dynamic or on the micro level by investigating the wealth distributions of the agents.Keywords: artificial stock markets, market dynamics, bounded rationality, agent based simulation, learning, interaction, social networks
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