Search results for: space structures
5473 The Assessment of Natural Ventilation Performance for Thermal Comfort in Educational Space: A Case Study of Design Studio in the Arab Academy for Science and Technology, Alexandria
Authors: Alaa Sarhan, Rania Abd El Gelil, Hana Awad
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Through the last decades, the impact of thermal comfort on the working performance of users and occupants of an indoor space has been a concern. Research papers concluded that natural ventilation quality directly impacts the levels of thermal comfort. Natural ventilation must be put into account during the design process in order to improve the inhabitant's efficiency and productivity. One example of daily long-term occupancy spaces is educational facilities. Many individuals spend long times receiving a considerable amount of knowledge, and it takes additional time to apply this knowledge. Thus, this research is concerned with user's level of thermal comfort in design studios of educational facilities. The natural ventilation quality in spaces is affected by a number of parameters including orientation, opening design, and many other factors. This research aims to investigate the conscious manipulation of the physical parameters of the spaces and its impact on natural ventilation performance which subsequently affects thermal comfort of users. The current research uses inductive and deductive methods to define natural ventilation design considerations, which are used in a field study in a studio in the university building in Alexandria (AAST) to evaluate natural ventilation performance through analyzing and comparing the current case to the developed framework and conducting computational fluid dynamics simulation. Results have proved that natural ventilation performance is successful by only 50% of the natural ventilation design framework; these results are supported by CFD simulation.Keywords: educational buildings, natural ventilation, , mediterranean climate, thermal comfort
Procedia PDF Downloads 2285472 Enhancing AI for Global Impact: Conversations on Improvement and Societal Benefits
Authors: C. P. Chukwuka, E. V. Chukwuka, F. Ukwadi
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This paper focuses on the advancement and societal impact of artificial intelligence (AI) systems. It explores the need for a theoretical framework in corporate governance, specifically in the context of 'hybrid' companies that have a mix of private and government ownership. The paper emphasizes the potential of AI to address challenges faced by these companies and highlights the importance of the less-explored state model in corporate governance. The aim of this research is to enhance AI systems for global impact and positive societal outcomes. It aims to explore the role of AI in refining corporate governance in hybrid companies and uncover nuanced insights into complex ownership structures. The methodology involves leveraging the capabilities of AI to address the challenges faced by hybrid companies in corporate governance. The researchers will analyze existing theoretical frameworks in corporate governance and integrate AI systems to improve problem-solving and understanding of intricate systems. The paper suggests that improved AI systems have the potential to shape a more informed and responsible corporate landscape. AI can uncover nuanced insights and navigate complex ownership structures in hybrid companies, leading to greater efficacy and positive societal outcomes. The theoretical importance of this research lies in the exploration of the role of AI in corporate governance, particularly in the context of hybrid companies. By integrating AI systems, the paper highlights the potential for improved problem-solving and understanding of intricate systems, contributing to a more informed and responsible corporate landscape. The data for this research will be collected from existing literature on corporate governance, specifically focusing on hybrid companies. Additionally, data on AI capabilities and their application in corporate governance will be collected. The collected data will be analyzed through a systematic review of existing theoretical frameworks in corporate governance. The researchers will also analyze the capabilities of AI systems and their potential application in addressing the challenges faced by hybrid companies. The findings will be synthesized and compared to identify patterns and potential improvements. The research concludes that AI systems have the potential to enhance corporate governance in hybrid companies, leading to greater efficacy and positive societal outcomes. By leveraging AI capabilities, nuanced insights can be uncovered, and complex ownership structures can be navigated, shaping a more informed and responsible corporate landscape. The findings highlight the importance of integrating AI in refining problem-solving and understanding intricate systems for global impact.Keywords: advancement, artificial intelligence, challenges, societal impact
Procedia PDF Downloads 605471 Green Design Study of Prefabricated Community Control Measures in Response to Public Health Emergencies
Authors: Enjia Zhang
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During the prevention and control of the COVID-19 pandemic, all communities in China were gated and under strict management, which was highly effective in preventing the spread of the epidemic from spreading. Based on the TRIZ theory, this paper intends to propose green design strategies of community control in response to public health emergencies and to optimize community control facilities according to the principle of minimum transformation. Through the questionnaire method, this paper investigates and summarizes the situation and problems of community control during the COVID-19 pandemic. Based on these problems, the TRIZ theory is introduced to figure out the problems and associates them with prefabricated facilities. Afterward, the innovation points and solutions of prefabricated community control measures are proposed by using the contradiction matrix. This paper summarizes the current situation of community control under public health emergencies and concludes the problems such as simple forms of temporary roadblocks, sudden increase of community traffic pressure, and difficulties to access public spaces. The importance of entrance and exit control in community control is emphasized. Therefore, the community control measures are supposed to focus on traffic control, and the external access control measures, including motor vehicles, non-motor vehicles, residents and non-residents access control, and internal public space access control measures, including public space control shared with the society or adjacent communities, are proposed in order to make the community keep the open characteristics and have the flexibility to deal with sudden public health emergencies in the future.Keywords: green design, community control, prefabricated structure, public health emergency
Procedia PDF Downloads 1325470 Implementing 3D Printing for 3D Digital Modeling in the Classroom
Authors: Saritdikhun Somasa
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3D printing fabrication has empowered many artists in many fields. Artists who work in stop motion, 3D modeling, toy design, product design, sculpture, and fine arts become one-stop shop operations–where they can design, prototype, and distribute their designs for commercial or fine art purposes. The author has developed a digital sculpting course that fosters digital software, peripheral hardware, and 3D printing with traditional sculpting concept techniques to address the complexities of this multifaceted process, allowing the students to produce complex 3d-printed work. The author will detail the preparation and planning for pre- to post-process 3D printing elements, including software, materials, space, equipment, tools, and schedule consideration for small to medium figurine design statues in a semester-long class. In addition, the author provides insight into teaching challenges in the non-studio space that requires students to work intensively on post-printed models to assemble parts, finish, and refine the 3D printed surface. Even though this paper focuses on the 3D printing processes and techniques for small to medium design statue projects for the Digital Media program, the author hopes the paper will benefit other fields of study such as craft practices, product design, and fine-arts programs. Other schools that might implement 3D printing and fabrication in their programs will find helpful information in this paper, such as a teaching plan, choices of equipment and materials, adaptation for non-studio spaces, and putting together a complete and well-resolved project for students.Keywords: 3D digital modeling, 3D digital sculpting, 3D modeling, 3D printing, 3D digital fabrication
Procedia PDF Downloads 1075469 Evaluating Daylight Performance in an Office Environment in Malaysia, Using Venetian Blind System: Case Study
Authors: Fatemeh Deldarabdolmaleki, Mohamad Fakri Zaky Bin Ja'afar
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Having a daylit space together with view results in a pleasant and productive environment for office employees. A daylit space is a space which utilizes daylight as a basic source of illumination to fulfill user’s visual demands and minimizes the electric energy consumption. Malaysian weather is hot and humid all over the year because of its location in the equatorial belt. however, because most of the commercial buildings in Malaysia are air-conditioned, huge glass windows are normally installed in order to keep the physical and visual relation between inside and outside. As a result of climatic situation and mentioned new trend, an ordinary office has huge heat gain, glare, and discomfort for occupants. Balancing occupant’s comfort and energy conservation in a tropical climate is a real challenge. This study concentrates on evaluating a venetian blind system using per pixel analyzing tools based on the suggested cut-out metrics by the literature. Workplace area in a private office room has been selected as a case study. Eight-day measurement experiment was conducted to investigate the effect of different venetian blind angles in an office area under daylight conditions in Serdang, Malaysia. The study goal was to explore daylight comfort of a commercially available venetian blind system, its’ daylight sufficiency and excess (8:00 AM to 5 PM) as well as Glare examination. Recently developed software, analyzing High Dynamic Range Images (HDRI captured by CCD camera), such as radiance based Evalglare and hdrscope help to investigate luminance-based metrics. The main key factors are illuminance and luminance levels, mean and maximum luminance, daylight glare probability (DGP) and luminance ratio of the selected mask regions. The findings show that in most cases, morning session needs artificial lighting in order to achieve daylight comfort. However, in some conditions (e.g. 10° and 40° slat angles) in the second half of day the workplane illuminance level exceeds the maximum of 2000 lx. Generally, a rising trend is discovered toward mean window luminance and the most unpleasant cases occur after 2 P.M. Considering the luminance criteria rating, the uncomfortable conditions occur in the afternoon session. Surprisingly in no blind condition, extreme case of window/task ratio is not common. Studying the daylight glare probability, there is not any DGP value higher than 0.35 in this experiment.Keywords: daylighting, energy simulation, office environment, Venetian blind
Procedia PDF Downloads 2635468 Potential Risks of Using Disconnected Composite Foundation Systems in Active Seismic Zones
Authors: Mohamed ElMasry, Ahmad Ragheb, Tareq AbdelAziz, Mohamed Ghazy
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Choosing the suitable infrastructure system is becoming more challenging with the increase in demand for heavier structures contemporarily. This is the case where piled raft foundations have been widely used around the world to support heavy structures without extensive settlement. In the latter system, piles are rigidly connected to the raft, and most of the load goes to the soil layer on which the piles are bearing. In spite of that, when soil profiles contain thicker soft clay layers near the surface, or at relatively shallow depths, it is unfavorable to use the rigid piled raft foundation system. Consequently, the disconnected piled raft system was introduced as an alternative approach for the rigidly connected system. In this system, piles are disconnected from the raft using a cushion of soil, mostly of a granular interlayer. The cushion is used to redistribute the stresses among the piles and the subsoil. Piles are also used to stiffen the subsoil, and by this way reduce the settlement without being rigidly connected to the raft. However, the seismic loading effect on such disconnected foundation systems remains a problem, since the soil profiles may include thick clay layers which raise risks of amplification of the dynamic earthquake loads. In this paper, the effects of seismic behavior on the connected and disconnected piled raft systems are studied through a numerical model using Midas GTS NX Software. The study concerns the soil-structure interaction and the expected behavior of the systems. Advantages and disadvantages of each foundation approach are studied, and a comparison between the results are presented to show the effects of using disconnected piled raft systems in highly seismic zones. This was done by showing the excitation amplification in each of the foundation systems.Keywords: soil-structure interaction, disconnected piled-raft, risks, seismic zones
Procedia PDF Downloads 2705467 Innovative Design Considerations for Adaptive Spacecraft
Authors: K. Parandhama Gowd
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Space technologies have changed the way we live in the present day society and manage many aspects of our daily affairs through Remote sensing, Navigation & Communications. Further, defense and military usage of spacecraft has increased tremendously along with civilian purposes. The number of satellites deployed in space in Low Earth Orbit (LEO), Medium Earth Orbit (MEO), and the Geostationary Orbit (GEO) has gone up. The dependency on remote sensing and operational capabilities are most invariably to be exploited more and more in future. Every country is acquiring spacecraft in one way or other for their daily needs, and spacecraft numbers are likely to increase significantly and create spacecraft traffic problems. The aim of this research paper is to propose innovative design concepts for adaptive spacecraft. The main idea here is to improve existing design methods of spacecraft design and development to further improve upon design considerations for futuristic adaptive spacecraft with inbuilt features for automatic adaptability and self-protection. In other words, the innovative design considerations proposed here are to have future spacecraft with self-organizing capabilities for orbital control and protection from anti-satellite weapons (ASAT). Here, an attempt is made to propose design and develop futuristic spacecraft for 2030 and beyond due to tremendous advancements in VVLSI, miniaturization, and nano antenna array technologies, including nano technologies are expected.Keywords: satellites, low earth orbit (LEO), medium earth orbit (MEO), geostationary earth orbit (GEO), self-organizing control system, anti-satellite weapons (ASAT), orbital control, radar warning receiver, missile warning receiver, laser warning receiver, attitude and orbit control systems (AOCS), command and data handling (CDH)
Procedia PDF Downloads 2985466 Service Life Study of Polymers Used in Renovation of Heritage Buildings and Other Structures
Authors: Parastou Kharazmi
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Degradation of building materials particularly pipelines causes environmental damage during renovation or replacement and is a time consuming and costly process. Rehabilitation by polymer composites is a solution for renovation of degraded pipeline in heritage buildings and other structures which are less costly, faster and causes less damage to the environment; however, it is still not clear for how long these materials can perform as expected in the field and working condition. To study their service life, two types of composites based on Epoxy and Polyester resins have been evaluated by accelerated exposure and field exposure. The primary degradation agent used in accelerated exposure has been cycling temperature with half of the tests performed in presence of water. Thin films of materials used in accelerated testing were prepared in laboratory by using the same amount of material as well as technique of multi-layers application used in majority of the field installations. Extreme intensity levels of degradation agents have been used only to evaluate materials properties and as also mentioned in ISO 15686, are not directly correlated with degradation mechanisms that would be experienced in service. In the field exposure study, the focus has been to identify possible failure modes, causes, and effects. In field exposure, it has been observed that there are other degradation agents present which can be investigated further such as presence of contaminants and rust before application which prevents formation of a uniform layer of polymer or incompatibility between dissimilar materials. This part of the study also highlighted the importance of application’s quality of the materials in the field for providing the expected performance and service life. Results from extended accelerated exposure and field exposure can help in choosing inspection techniques, establishing the primary degradation agents and can be used for ageing exposure programs with clarifying relationship between different exposure periods and sites.Keywords: building, renovation, service life, pipelines
Procedia PDF Downloads 1915465 Management of Cultural Heritage: Bologna Gates
Authors: Alfonso Ippolito, Cristiana Bartolomei
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A growing demand is felt today for realistic 3D models enabling the cognition and popularization of historical-artistic heritage. Evaluation and preservation of Cultural Heritage is inextricably connected with the innovative processes of gaining, managing, and using knowledge. The development and perfecting of techniques for acquiring and elaborating photorealistic 3D models, made them pivotal elements for popularizing information of objects on the scale of architectonic structures.Keywords: cultural heritage, databases, non-contact survey, 2D-3D models
Procedia PDF Downloads 4255464 Numerical Study of Splay Anchors in CFRP-Strengthened Concrete Beams
Authors: Asal Pournaghshband, Mohammed A. Zaki
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This paper presents a detailed numerical investigation into the structural performance of splay anchor configurations for strengthening concrete beams with Carbon Fiber Reinforced Polymer (CFRP) sheets. CFRP is widely used in retrofitting concrete structures to improve flexural strength and extend service life. However, premature debonding limits the tensile capacity of CFRP sheets, reducing the effectiveness of these applications. This study addresses this limitation by exploring the potential of splay anchors as an emerging anchorage technique that mitigates debonding issues through improved load transfer mechanisms. Building on existing experimental studies, the research uses ABAQUS software to validate different splay anchor configurations and simulate real-world performance. The parametric study examines key anchor parameters, including diameter, spacing, and embedment depth, to evaluate their effects on bond strength, load distribution, and the flexural capacity of strengthened beams. Systematic analysis of these parameters allows for identifying configurations that enhance debonding resistance and increase the load-carrying capacity of CFRP-strengthened beams. Improved debonding resistance contributes to greater structural durability, reduced maintenance costs, and extended service life for retrofitted structures, particularly relevant for aging infrastructure like bridges and buildings. This approach not only advances sustainable retrofitting practices but also provides practical solutions tailored to infrastructure demands.Keywords: CFRP strengthening, splay anchors, concrete beams, structural retrofitting, numerical analysis
Procedia PDF Downloads 175463 Dynamics and Advection in a Vortex Parquet on the Plane
Authors: Filimonova Alexanra
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Inviscid incompressible fluid flows are considered. The object of the study is a vortex parquet – a structure consisting of distributed vortex spots of different directions, occupying the entire plane. The main attention is paid to the study of advection processes of passive particles in the corresponding velocity field. The dynamics of the vortex structures is considered in a rectangular region under the assumption that periodic boundary conditions are imposed on the stream function. Numerical algorithms are based on the solution of the initial-boundary value problem for nonstationary Euler equations in terms of vorticity and stream function. For this, the spectral-vortex meshless method is used. It is based on the approximation of the stream function by the Fourier series cut and the approximation of the vorticity field by the least-squares method from its values in marker particles. A vortex configuration, consisting of four vortex patches is investigated. Results of a numerical study of the dynamics and interaction of the structure are presented. The influence of the patch radius and the relative position of positively and negatively directed patches on the processes of interaction and mixing is studied. The obtained results correspond to the following possible scenarios: the initial configuration does not change over time; the initial configuration forms a new structure, which is maintained for longer times; the initial configuration returns to its initial state after a certain period of time. The processes of mass transfer of vorticity by liquid particles on a plane were calculated and analyzed. The results of a numerical analysis of the particles dynamics and trajectories on the entire plane and the field of local Lyapunov exponents are presented.Keywords: ideal fluid, meshless methods, vortex structures in liquids, vortex parquet.
Procedia PDF Downloads 685462 Seeking Compatibility between Green Infrastructure and Recentralization: The Case of Greater Toronto Area
Authors: Sara Saboonian, Pierre Filion
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There are two distinct planning approaches attempting to transform the North American suburb so as to reduce its adverse environmental impacts. The first one, the recentralization approach, proposes intensification, multi-functionality and more reliance on public transit and walking. It thus offers an alternative to the prevailing low-density, spatial specialization and automobile dependence of the North American suburb. The second approach concentrates instead on the provision of green infrastructure, which rely on natural systems rather than on highly engineered solutions to deal with the infrastructure needs of suburban areas. There are tensions between these two approaches as recentralization generally overlooks green infrastructure, which can be space consuming (as in the case of water retention systems), and thus conflicts with the intensification goals of recentralization. The research investigates three Canadian planned suburban centres in the Greater Toronto Area, where recentralization is the current planning practice, despite rising awareness of the benefits of green infrastructure. Methods include reviewing the literature on green infrastructure planning, a critical analysis of the Ontario provincial plans for recentralization, surveying residents’ preferences regarding alternative suburban development models, and interviewing officials who deal with the local planning of the three centres. The case studies expose the difficulties in creating planned suburban centres that accommodate green infrastructure while adhering to recentralization principles. Until now, planners have been mostly focussed on recentralization at the expense of green infrastructure. In this context, the frequent lack of compatibility between recentralization and the space requirements of green infrastructure explains the limited presence of such infrastructures in planned suburban centres. Finally, while much attention has been given in the planning discourse to the economic and lifestyle benefits of recentralization, much less has been made of the wide range of advantages of green infrastructure, which explains limited public mobilization over the development of green infrastructure networks. The paper will concentrate on ways of combining recentralization with green infrastructure strategies and identify the aspects of the two approaches that are most compatible with each other. The outcome of such blending will marry high density, public-transit oriented developments, which generate walkability and street-level animation, with the presence of green space, naturalized settings and reliance on renewable energy. The paper will advance a planning framework that will fuse green infrastructure with recentralization, thus ensuring the achievement of higher density and reduced reliance on the car along with the provision of critical ecosystem services throughout cities. This will support and enhance the objectives of both green infrastructure and recentralization.Keywords: environmental-based planning, green infrastructure, multi-functionality, recentralization
Procedia PDF Downloads 1355461 Hydroxyapatite Based Porous Scaffold for Tooth Tissue Engineering
Authors: Pakize Neslihan Taslı, Alev Cumbul, Gul Merve Yalcın, Fikrettin Sahin
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A key experimental trial in the regeneration of large oral and craniofacial defects is the neogenesis of osseous and ligamentous interfacial structures. Currently, oral regenerative medicine strategies are unpredictable for repair of tooth supporting tissues destroyed as a consequence of trauma, chronic infection or surgical resection. A different approach combining the gel-casting method with Hydroxy Apatite HA-based scaffold and different cell lineages as a hybrid system leads to successively mimic the early stage of tooth development, in vitro. HA is widely accepted as a bioactive material for guided bone and tooth regeneration. In this study, it was reported that, HA porous scaffold preparation, characterization and evaluation of structural and chemical properties. HA is the main factor that exists in tooth and it is in harmony with structural, biological, and mechanical characteristics. Here, this study shows mimicking immature tooth at the late bell stage design and construction of HA scaffolds for cell transplantation of human Adipose Stem Cells (hASCs), human Bone Marrow Stem Cells (hBMSCs) and Gingival Epitelial cells for the formation of human tooth dentin-pulp-enamel complexes in vitro. Scaffold characterization was demonstrated by SEM, FTIR and pore size and density measurements. The biological contraction of dental tissues against each other was demonstrated by mRNA gene expressions, histopatologic observations and protein release profile by ELISA tecnique. The tooth shaped constructs with a pore size ranging from 150 to 300 µm arranged by gathering right amounts of materials provide interconnected macro-porous structure. The newly formed tissue like structures that grow and integrate within the HA designed constructs forming tooth cementum like tissue, pulp and bone structures. These findings are important as they emphasize the potential biological effect of the hybrid scaffold system. In conclusion, this in vitro study clearly demonstrates that designed 3D scaffolds shaped as a immature tooth at the late bell stage were essential to form enamel-dentin-pulp interfaces with an appropriate cell and biodegradable material combination. The biomimetic architecture achieved here is providing a promising platform for dental tissue engineering.Keywords: tooth regeneration, tissue engineering, adipose stem cells, hydroxyapatite tooth engineering, porous scaffold
Procedia PDF Downloads 2355460 Study of Heat Transfer through the Ground and its Accumulation Properties to Increase the Energy Efficiency of Underground Buildings
Authors: Sandeep Bandarwadkar, Tadas Zdankus
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To maintain a comfortable indoor temperature for its residents in the colder season, heating a building is necessary. Due to the expansion in the construction sectors, the consumption of heating energy is increasing. According to Eurostat data, in the European Union, the share of energy consumption of heating energy for space and cooling in residential buildings was around 63% in 2019. These figures indicate that heating energy still accounts for a significant portion of total energy consumption in Europe. Innovation is crucial to reduce energy consumption in buildings and achieve greater energy efficiency and sustainability. It can bring about new solutions that are smarter and more natural energy generation to reduce greenhouse gas emissions. The ground can serve as an effective and sustainable heat accumulator for heating and cooling. The temperature of the ground is higher than that of the ambient air in the colder period and lower in the warmer period. The building deep in the soil could use less thermal energy compared to the above-ground buildings that provide the same amount of thermal comfort. The temperature difference between the soil and the air inside the building decreases as the temperature of the soil increases. In progress, this process generates the condition that acts against heat loss. However, heat dissipates further to the consecutive layers and reaches thermal equilibrium. The charging of the ground by heat and its dissipation through the adjacent soil layers was investigated experimentally. The results of this research showed that 9% of the energy savings in partially underground buildings and 44.4% in completely underground buildings were derived from heating the space. Heat loss to the ground is treated as a charge of the soil by thermal energy. The dependence of the intensity of the charge on time was analysed and presented.Keywords: heat transfer, accumulation of heat, underground building, soil charge
Procedia PDF Downloads 765459 Detection of Alzheimer's Protein on Nano Designed Polymer Surfaces in Water and Artificial Saliva
Authors: Sevde Altuntas, Fatih Buyukserin
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Alzheimer’s disease is responsible for irreversible neural damage of brain parts. One of the disease markers is Amyloid-β 1-42 protein that accumulates in the brain in the form plaques. The basic problem for detection of the protein is the low amount of protein that cannot be detected properly in body liquids such as blood, saliva or urine. To solve this problem, tests like ELISA or PCR are proposed which are expensive, require specialized personnel and can contain complex protocols. Therefore, Surface-enhanced Raman Spectroscopy (SERS) a good candidate for detection of Amyloid-β 1-42 protein. Because the spectroscopic technique can potentially allow even single molecule detection from liquid and solid surfaces. Besides SERS signal can be improved by using nanopattern surface and also is specific to molecules. In this context, our study proposes to fabricate diagnostic test models that utilize Au-coated nanopatterned polycarbonate (PC) surfaces modified with Thioflavin - T to detect low concentrations of Amyloid-β 1-42 protein in water and artificial saliva medium by the enhancement of protein SERS signal. The nanopatterned PC surface that was used to enhance SERS signal was fabricated by using Anodic Alumina Membranes (AAM) as a template. It is possible to produce AAMs with different column structures and varying thicknesses depending on voltage and anodization time. After fabrication process, the pore diameter of AAMs can be arranged with dilute acid solution treatment. In this study, two different columns structures were prepared. After a surface modification to decrease their surface energy, AAMs were treated with PC solution. Following the solvent evaporation, nanopatterned PC films with tunable pillared structures were peeled off from the membrane surface. The PC film was then modified with Au and Thioflavin-T for the detection of Amyloid-β 1-42 protein. The protein detection studies were conducted first in water via this biosensor platform. Same measurements were conducted in artificial saliva to detect the presence of Amyloid Amyloid-β 1-42 protein. SEM, SERS and contact angle measurements were carried out for the characterization of different surfaces and further demonstration of the protein attachment. SERS enhancement factor calculations were also completed via experimental results. As a result, our research group fabricated diagnostic test models that utilize Au-coated nanopatterned polycarbonate (PC) surfaces modified with Thioflavin-T to detect low concentrations of Alzheimer’s Amiloid – β protein in water and artificial saliva medium. This work was supported by The Scientific and Technological Research Council of Turkey (TUBITAK) Grant No: 214Z167.Keywords: alzheimer, anodic aluminum oxide, nanotopography, surface enhanced Raman spectroscopy
Procedia PDF Downloads 2945458 Investigation of Detectability of Orbital Objects/Debris in Geostationary Earth Orbit by Microwave Kinetic Inductance Detectors
Authors: Saeed Vahedikamal, Ian Hepburn
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Microwave Kinetic Inductance Detectors (MKIDs) are considered as one of the most promising photon detectors of the future in many Astronomical applications such as exoplanet detections. The MKID advantages stem from their single photon sensitivity (ranging from UV to optical and near infrared), photon energy resolution and high temporal capability (~microseconds). There has been substantial progress in the development of these detectors and MKIDs with Megapixel arrays is now possible. The unique capability of recording an incident photon and its energy (or wavelength) while also registering its time of arrival to within a microsecond enables an array of MKIDs to produce a four-dimensional data block of x, y, z and t comprising x, y spatial, z axis per pixel spectral and t axis per pixel which is temporal. This offers the possibility that the spectrum and brightness variation for any detected piece of space debris as a function of time might offer a unique identifier or fingerprint. Such a fingerprint signal from any object identified in multiple detections by different observers has the potential to determine the orbital features of the object and be used for their tracking. Modelling performed so far shows that with a 20 cm telescope located at an Astronomical observatory (e.g. La Palma, Canary Islands) we could detect sub cm objects at GEO. By considering a Lambertian sphere with a 10 % reflectivity (albedo of the Moon) we anticipate the following for a GEO object: 10 cm object imaged in a 1 second image capture; 1.2 cm object for a 70 second image integration or 0.65 cm object for a 4 minute image integration. We present details of our modelling and the potential instrument for a dedicated GEO surveillance system.Keywords: space debris, orbital debris, detection system, observation, microwave kinetic inductance detectors, MKID
Procedia PDF Downloads 1005457 Micro-Transformation Strategy Of Residential Transportation Space Based On The Demand Of Residents: Taking A Residential District In Wuhan, China As An Example
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With the acceleration of urbanization and motorization in China, the scale of cities and the travel distance of residents are constantly expanding, and the number of cars is continuously increasing, so the urban traffic problem is more and more serious. Traffic congestion, environmental pollution, energy consumption, travel safety and direct interference between traffic and other urban activities are increasingly prominent problems brought about by motorized development. This not only has a serious impact on the lives of the residents but also has a major impact on the healthy development of the city. The paper found that, in order to solve the development of motorization, a number of problems will arise; urban planning and traffic planning and design in residential planning often take into account the development of motorized traffic but neglects the demand for street life. This kind of planning has resulted in the destruction of the traditional communication space of the residential area, the pollution of noise and exhaust gas, and the potential safety risks of the residential area, which has disturbed the previously quiet and comfortable life of the residential area, resulting in the inconvenience of residents' life and the loss of street vitality. Based on these facts, this paper takes a residential area in Wuhan as the research object, through the actual investigation and research, from the perspective of micro-transformation analysis, combined with the concept of traffic micro-reconstruction governance. And research puts forward the residential traffic optimization strategies such as strengthening the interaction and connection between the residential area and the urban street system, street traffic classification and organization.Keywords: micro-transformation, residential traffic, residents demand, traffic microcirculation
Procedia PDF Downloads 1195456 Molecular Docking Analysis of Flavonoids Reveal Potential of Eriodictyol for Breast Cancer Treatment
Authors: Nicole C. Valdez, Vincent L. Borromeo, Conrad C. Chong, Ahmad F. Mazahery
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Breast cancer is the most prevalent cancer worldwide, where the majority of cases are estrogen-receptor positive and involve 2 receptor proteins. The binding of estrogen to estrogen receptor alpha (ERα) promotes breast cancer growth, while it's binding to estrogen-receptor beta (ERβ) inhibits tumor growth. While natural products have been a promising source of chemotherapeutic agents, the challenge remains in finding a bioactive compound that specifically targets cancer cells, minimizing side effects on normal cells. Flavonoids are natural products that act as phytoestrogens and induce the same response as estrogen. They are able to compete with estrogen for binding to ERα; however, it has a higher binding affinity for ERβ. Their abundance in nature and low toxicity make them a potential candidate for breast cancer treatment. This study aimed to determine which particular flavonoids can specifically recognize ERβ and potentially be used for breast cancer treatment through molecular docking. A total of 206 flavonoids comprised of 97 isoflavones and 109 flavanones were collected from ZINC15, while the 3D structures of ERβ and ERα were obtained from Protein Data Bank. These flavonoid subclasses were chosen as they bind more strongly to ERs due to their chemical structure. The structures of the flavonoid ligands were converted using Open Babel, while the estrogen receptor protein structures were prepared using Autodock MGL Tools. The optimal binding site was found using BIOVIA Discovery Studio Visualizer before docking all flavonoids on both ERβ and ERα through Autodock Vina. Genistein is a flavonoid that exhibits anticancer effects by binding to ERβ, so its binding affinity was used as a baseline. Eriodictyol and 4”,6”-Di-O-Galloylprunin both exceeded genistein’s binding affinity for ERβ and was lower than its binding affinity for ERα. Of the two, eriodictyol was pursued due to its antitumor properties on a lung cancer cell line and on glioma cells. It is able to arrest the cell cycle at the G2/M phase by inhibiting the mTOR/PI3k/Akt cascade and is able to induce apoptosis via the PI3K/Akt/NF-kB pathway. Protein pathway and gene analysis were also conducted using ChEMBL and PANTHER and it was shown that eriodictyol might induce anticancer effects through the ROS1, CA7, KMO, and KDM1A genes which are involved in cell proliferation in breast cancer, non-small cell lung cancer, and other diseases. The high binding affinity of eriodictyol to ERβ, as well as its potential affected genes and antitumor effects, therefore, make it a candidate for the development of new breast cancer treatment. Verification through in vitro experiments such as checking the upregulation and downregulation of genes through qPCR and checking cell cycle arrest using a flow cytometry assay is recommended.Keywords: breast cancer, estrogen receptor, flavonoid, molecular docking
Procedia PDF Downloads 925455 Eco-Parcel As a Semi-Qualitative Approach to Support Environmental Impacts Assessments in Nature-Based Tourism Destinations
Authors: Halima Kilungu, Pantaleo, K. T. Munishi
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Climate and land-cover change affect nature-based tourism (NBT) due to its attractions' close connection to natural environments and climate. Thus, knowledge of how each attraction reacts to the changing environments and devising simple yet science based approaches to respond to these changes from a tourism perspective in space and time is timely. Nevertheless, no specific approaches exist to address the knowledge gap. The eco-parcel approach is devised to address the gap and operationalized in Serengeti and Kilimanjaro National Parks: the most climate-sensitive NBT destinations in Africa. The approach is partly descriptive and has three simple steps: (1) to identify and define tourist attractions (i.e. biotic and abiotic attractions). This creates an important database of the most poorly kept information on attractions' types in NBT destinations. (2) To create a spatial and temporal link of each attraction and describe its characteristic environments (e.g. vegetation, soil, water and rock outcrops). This is the most limited attractions' information yet important as a proxy of changes in attractions. (3) To assess the importance of individual attractions for tourism based on tourists' preferences. This information enables an accurate assessment of the value of individual attractions for tourism. The importance of the eco-parcel approach is that it describes how each attraction emerges from and is connected to specific environments, which define its attractiveness in space and time. This information allows accurate assessment of the likely losses or gains of individual attractions when climate or environment changes in specific destinations and equips tourism stakeholders with informed responses.Keywords: climate change, environmental change, nature-based tourism, Serengeti National Park, Kilimanjaro National Park
Procedia PDF Downloads 1255454 Surface-Enhanced Raman Spectroscopy-Based Detection of SARS-CoV-2 Through In Situ One-pot Electrochemical Synthesis of 3D Au-Lysate Nanocomposite Structures on Plasmonic Au Electrodes
Authors: Ansah Iris Baffour, Dong-Ho Kim, Sung-Gyu Park
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The ongoing COVID-19 pandemic, caused by the SARS-CoV-2 virus and is gradually shifting to an endemic phase which implies the outbreak is far from over and will be difficult to eradicate. Global cooperation has led to unified precautions that aim to suppress epidemiological spread (e.g., through travel restrictions) and reach herd immunity (through vaccinations); however, the primary strategy to restrain the spread of the virus in mass populations relies on screening protocols that enable rapid on-site diagnosis of infections. Herein, we employed surface enhanced Raman spectroscopy (SERS) for the rapid detection of SARS-CoV-2 lysate on an Au-modified Au nanodimple(AuND)electrode. Through in situone-pot Au electrodeposition on the AuND electrode, Au-lysate nanocomposites were synthesized, generating3D internal hotspots for large SERS signal enhancements within 30 s of the deposition. The capture of lysate into newly generated plasmonic nanogaps within the nanocomposite structures enhanced metal-spike protein contact in 3D spaces and served as hotspots for sensitive detection. The limit of detection of SARS-CoV-2 lysate was 5 x 10-2 PFU/mL. Interestingly, ultrasensitive detection of the lysates of influenza A/H1N1 and respiratory syncytial virus (RSV) was possible, but the method showed ultimate selectivity for SARS-CoV-2 in lysate solution mixtures. We investigated the practical application of the approach for rapid on-site diagnosis by detecting SARS-CoV-2 lysate spiked in normal human saliva at ultralow concentrations. The results presented demonstrate the reliability and sensitivity of the assay for rapid diagnosis of COVID-19.Keywords: label-free detection, nanocomposites, SARS-CoV-2, surface-enhanced raman spectroscopy
Procedia PDF Downloads 1255453 Forging A Distinct Understanding of Implicit Bias
Authors: Benjamin D Reese Jr
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Implicit bias is understood as unconscious attitudes, stereotypes, or associations that can influence the cognitions, actions, decisions, and interactions of an individual without intentional control. These unconscious attitudes or stereotypes are often targeted toward specific groups of people based on their gender, race, age, perceived sexual orientation or other social categories. Since the late 1980s, there has been a proliferation of research that hypothesizes that the operation of implicit bias is the result of the brain needing to process millions of bits of information every second. Hence, one’s prior individual learning history provides ‘shortcuts’. As soon as one see someone of a certain race, one have immediate associations based on their past learning, and one might make assumptions about their competence, skill, or danger. These assumptions are outside of conscious awareness. In recent years, an alternative conceptualization has been proposed. The ‘bias of crowds’ theory hypothesizes that a given context or situation influences the degree of accessibility of particular biases. For example, in certain geographic communities in the United States, there is a long-standing and deeply ingrained history of structures, policies, and practices that contribute to racial inequities and bias toward African Americans. Hence, negative biases among groups of people towards African Americans are more accessible in such contexts or communities. This theory does not focus on individual brain functioning or cognitive ‘shortcuts.’ Therefore, attempts to modify individual perceptions or learning might have negligible impact on those embedded environmental systems or policies that are within certain contexts or communities. From the ‘bias of crowds’ perspective, high levels of racial bias in a community can be reduced by making fundamental changes in structures, policies, and practices to create a more equitable context or community rather than focusing on training or education aimed at reducing an individual’s biases. The current paper acknowledges and supports the foundational role of long-standing structures, policies, and practices that maintain racial inequities, as well as inequities related to other social categories, and highlights the critical need to continue organizational, community, and national efforts to eliminate those inequities. It also makes a case for providing individual leaders with a deep understanding of the dynamics of how implicit biases impact cognitions, actions, decisions, and interactions so that those leaders might more effectively develop structural changes in the processes and systems under their purview. This approach incorporates both the importance of an individual’s learning history as well as the important variables within the ‘bias of crowds’ theory. The paper also offers a model for leadership education, as well as examples of structural changes leaders might consider.Keywords: implicit bias, unconscious bias, bias, inequities
Procedia PDF Downloads 175452 Effect of Green Roofs to Prevent the Dissipation of Energy in Mountainous Areas
Authors: Mina Ganji Morad, Maziar Azadisoleimanieh, Sina Ganji Morad
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A green roof is formed by green plants alive and has many positive impacts in the regional climatic, as well as indoor. Green roof system to prevent solar radiation plays a role in the cooling space. The cooling is done by reducing thermal fluctuations on the exterior of the roof and by increasing the roof heat capacity which cause to keep the space under the roof cool in the summer and heating rate increases during the winter. A roof garden is one of the recommended ways to reduce energy consumption in large cities. Despite the scale of the city green roofs have effective functions, such as beautiful view of city and decontaminating the urban landscape and reduce mental stress, and in an exchange of energy and heat from outside to inside spaces. This article is based on a review of 20 articles and 10 books and valid survey results on the positive effects of green roofs to prevent energy waste in the building. According to these publications, three of the conventional roof, green roof typical and green roof with certain administrative details (layers of glass) and the use of resistant plants and shrubs have been analyzed and compared their heat transfer. The results of these studies showed that one of the best green roof systems for mountainous climate is tree and shrub system that in addition to being resistant to climate change in mountainous regions, will benefit from the other advantages of green roof. Due to the severity of climate change in mountainous areas it is essential to prevent the waste of buildings heating and cooling energy. Proper climate design can greatly help to reduce energy.Keywords: green roof, heat transfer, reducing energy consumption, mountainous areas, sustainable architecture
Procedia PDF Downloads 4025451 Examining Postcolonial Corporate Power Structures through the Lens of Development Induced Projects in Africa
Authors: Omogboyega Abe
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This paper examines the relationships between socio-economic inequalities of power, race, wealth engendered by corporate structure, and domination in postcolonial Africa. The paper further considers how land as an epitome of property and power for the locals paved the way for capitalist accumulation and control in the hands of transnational corporations. European colonization of Africa was contingent on settler colonialism, where properties, including land, were re-modified as extractive resources for primitive accumulation. In developing Africa's extractive resources, transnational corporations (TNCs) usurped states' structures and domination over native land. The usurpation/corporate capture that exists to date has led to remonstrations and arguably a counter-productive approach to development projects. In some communities, the mention of extractive companies triggers resentment. The paradigm of state capture and state autonomy is simply inadequate to either describe or resolve the play of forces or actors responsible for severe corporate-induced human rights violations in emerging markets. Moreover, even if the deadly working conditions are conceived as some regulatory failure, it is tough to tell whose failure. The analysis in this paper is that the complexity and ambiguity evidenced by the multiple regimes and political and economic forces shaping production, consumption, and distribution of socio-economic variables are not exceptional in emerging markets. Instead, the varied experience in developing countries provides a window for seeing what we face in understanding and theorizing the structure and operation of the global economic and regulatory order in general.Keywords: colonial, emerging markets, business, human rights, corporation
Procedia PDF Downloads 705450 Computation of Residual Stresses in Human Face Due to Growth
Authors: M. A. Askari, M. A. Nazari, P. Perrier, Y. Payan
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Growth and remodeling of biological structures have gained lots of attention over the past decades. Determining the response of the living tissues to the mechanical loads is necessary for a wide range of developing fields such as, designing of prosthetics and optimized surgery operations. It is a well-known fact that biological structures are never stress-free, even when externally unloaded. The exact origin of these residual stresses is not clear, but theoretically growth and remodeling is one of the main sources. Extracting body organs from medical imaging, does not produce any information regarding the existing residual stresses in that organ. The simplest cause of such stresses is the gravity since an organ grows under its influence from its birth. Ignoring such residual stresses might cause erroneous results in numerical simulations. Accounting for residual stresses due to tissue growth can improve the accuracy of mechanical analysis results. In this paper, we have implemented a computational framework based on fixed-point iteration to determine the residual stresses due to growth. Using nonlinear continuum mechanics and the concept of fictitious configuration we find the unknown stress-free reference configuration which is necessary for mechanical analysis. To illustrate the method, we apply it to a finite element model of healthy human face whose geometry has been extracted from medical images. We have computed the distribution of residual stress in facial tissues, which can overcome the effect of gravity and cause that tissues remain firm. Tissue wrinkles caused by aging could be a consequence of decreasing residual stress and not counteracting the gravity. Considering these stresses has important application in maxillofacial surgery. It helps the surgeons to predict the changes after surgical operations and their consequences.Keywords: growth, soft tissue, residual stress, finite element method
Procedia PDF Downloads 3585449 A Hybrid LES-RANS Approach to Analyse Coupled Heat Transfer and Vortex Structures in Separated and Reattached Turbulent Flows
Authors: C. D. Ellis, H. Xia, X. Chen
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Experimental and computational studies investigating heat transfer in separated flows have been of increasing importance over the last 60 years, as efforts are being made to understand and improve the efficiency of components such as combustors, turbines, heat exchangers, nuclear reactors and cooling channels. Understanding of not only the time-mean heat transfer properties but also the unsteady properties is vital for design of these components. As computational power increases, more sophisticated methods of modelling these flows become available for use. The hybrid LES-RANS approach has been applied to a blunt leading edge flat plate, utilising a structured grid at a moderate Reynolds number of 20300 based on the plate thickness. In the region close to the wall, the RANS method is implemented for two turbulence models; the one equation Spalart-Allmaras model and Menter’s two equation SST k-ω model. The LES region occupies the flow away from the wall and is formulated without any explicit subgrid scale LES modelling. Hybridisation is achieved between the two methods by the blending of the nearest wall distance. Validation of the flow was obtained by assessing the mean velocity profiles in comparison to similar studies. Identifying the vortex structures of the flow was obtained by utilising the λ2 criterion to identify vortex cores. The qualitative structure of the flow compared with experiments of similar Reynolds number. This identified the 2D roll up of the shear layer, breaking down via the Kelvin-Helmholtz instability. Through this instability the flow progressed into hairpin like structures, elongating as they advanced downstream. Proper Orthogonal Decomposition (POD) analysis has been performed on the full flow field and upon the surface temperature of the plate. As expected, the breakdown of POD modes for the full field revealed a relatively slow decay compared to the surface temperature field. Both POD fields identified the most energetic fluctuations occurred in the separated and recirculation region of the flow. Latter modes of the surface temperature identified these levels of fluctuations to dominate the time-mean region of maximum heat transfer and flow reattachment. In addition to the current research, work will be conducted in tracking the movement of the vortex cores and the location and magnitude of temperature hot spots upon the plate. This information will support the POD and statistical analysis performed to further identify qualitative relationships between the vortex dynamics and the response of the surface heat transfer.Keywords: heat transfer, hybrid LES-RANS, separated and reattached flow, vortex dynamics
Procedia PDF Downloads 2325448 Material Chemistry Level Deformation and Failure in Cementitious Materials
Authors: Ram V. Mohan, John Rivas-Murillo, Ahmed Mohamed, Wayne D. Hodo
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Cementitious materials, an excellent example of highly complex, heterogeneous material systems, are cement-based systems that include cement paste, mortar, and concrete that are heavily used in civil infrastructure; though commonly used are one of the most complex in terms of the material morphology and structure than most materials, for example, crystalline metals. Processes and features occurring at the nanometer sized morphological structures affect the performance, deformation/failure behavior at larger length scales. In addition, cementitious materials undergo chemical and morphological changes gaining strength during the transient hydration process. Hydration in cement is a very complex process creating complex microstructures and the associated molecular structures that vary with hydration. A fundamental understanding can be gained through multi-scale level modeling for the behavior and properties of cementitious materials starting from the material chemistry level atomistic scale to further explore their role and the manifested effects at larger length and engineering scales. This predictive modeling enables the understanding, and studying the influence of material chemistry level changes and nanomaterial additives on the expected resultant material characteristics and deformation behavior. Atomistic-molecular dynamic level modeling is required to couple material science to engineering mechanics. Starting at the molecular level a comprehensive description of the material’s chemistry is required to understand the fundamental properties that govern behavior occurring across each relevant length scale. Material chemistry level models and molecular dynamics modeling and simulations are employed in our work to describe the molecular-level chemistry features of calcium-silicate-hydrate (CSH), one of the key hydrated constituents of cement paste, their associated deformation and failure. The molecular level atomic structure for CSH can be represented by Jennite mineral structure. Jennite has been widely accepted by researchers and is typically used to represent the molecular structure of the CSH gel formed during the hydration of cement clinkers. This paper will focus on our recent work on the shear and compressive deformation and failure behavior of CSH represented by Jennite mineral structure that has been widely accepted by researchers and is typically used to represent the molecular structure of CSH formed during the hydration of cement clinkers. The deformation and failure behavior under shear and compression loading deformation in traditional hydrated CSH; effect of material chemistry changes on the predicted stress-strain behavior, transition from linear to non-linear behavior and identify the on-set of failure based on material chemistry structures of CSH Jennite and changes in its chemistry structure will be discussed.Keywords: cementitious materials, deformation, failure, material chemistry modeling
Procedia PDF Downloads 2915447 Spoken Rhetoric in Arabic Heritage
Authors: Ihab Al-Mokrani
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The Arabic heritage has two types of spoken rhetoric: the first type which al-Jaahiz calls “the rhetoric of the sign,” which means body language, and the rhetoric of silence which is of no less importance than the rhetoric of the sign, the speaker’s appearance and movements, etc. The second type is the spoken performance of utterances which bears written rhetoric arts like metaphor, simile, metonymy, etc. Rationale of the study: First: in spite of the factual existence of rhetorical phenomena in the Arabic heritage, there has been no contemporary study handling the spoken rhetoric in the Arabic heritage. Second: Arabic Civilization is originally a spoken one. Comparing the Arabic culture and civilization, from one side, to the Greek, roman or Pharaonic cultures and civilizations, from the other side, shows that the latter cultures and civilizations started and flourished written while the former started among illiterate people who had no interest in writing until recently. That sort of difference on the part of the Arabic culture and civilization created a rhetoric different from rhetoric in the other cultures and civilizations. Third: the spoken nature of the Arabic civilization influenced the Arabic rhetoric in the sense that specific rhetorical arts have been introduced matching that spoken nature. One of these arts is the art of concision which compensates for the absence of writing’s means of preserving the text. In addition, this interprets why many of the definitions of the Arabic rhetoric were defining rhetoric as the art of concision. Also, this interprets the fact that the literary genres known in the Arabic culture were limited by the available narrow space like poetry, anecdotes, and stories, while the literary genres in the Greek culture were of wide space as epics and drama. This is not of any contrast to the fact that some Arabic poetry would exceed 100 lines of poetry as Arabic poetry was based on the line organic unity, which means that every line could stand alone with a full meaning that is not dependent on the rest of the poem; and that last aspect has never happened in any culture other than the Arabic culture.Keywords: Arabic rhetoric, spoken rhetoric, Arabic heritage, culture
Procedia PDF Downloads 7775446 Perceptions and Spatial Realities: Women and the City of Limassol
Authors: Anna Papadopoulou
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Women’s relationship to the post-industrial city has been defined by a reciprocal relationship between women’s identity and urban form. Women’s place within the social structure has been influenced by often limiting conditions set by the built environment, and, concurrently, women’s active role in social processes has definitively impacted urban development. Cities in Cyprus present unique locations for urban investigations pertaining to gender because of the country’s particular urban history: unlike most prominent European cities that have experienced approximately five hundred years of urban growth spurred by industrial development, Cypriot cities did not begin to form until the end of the Ottoman occupation that occurred in the last quarter of the nineteenth century. Consequently, Cyprus’ urban history is distinctive in that it coincides with international awakenings towards gender equality. This paper is drawn from a study of a contemporary urban narrative of Limassolian women and aims to elucidate spatial and perceptual boundaries that are inherent, constructed and implied. Within the context of this study, gender - in its socially constructed form - becomes a tool for reading and understanding the urban landscape, as well as a vehicle to impact the production and consumption of space. The investigation evaluates urban changes through the lens of women’s entry into the workforce which is a profound event in the social process and consequently explores issues of space and time, connectivity, and access, perceptions and awareness. A narrative of gendered urbanism has been derived from semi-structured interviews where the findings are studied, organised, analysed and synthesised through a grounded theory approach. These qualitative findings have been complemented and specialised by a series of informal observations and mappings.Keywords: boundaries, gender, Limassol, urbanism
Procedia PDF Downloads 2375445 Laboratory Simulation of Subway Dynamic Stray Current Interference with Cathodically Protected Structures
Authors: Mohammad Derakhshani, Saeed Reza Allahkaram, Michael Isakani-Zakaria, Masoud Samadian, Hojat Sharifi Rasaey
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Dynamic stray currents tend to change their magnitude and polarity with time at their source which will create anodic and cathodic spots on a nearby interfered structure. To date, one of the biggest known dynamic stray current sources are DC traction systems. Laboratory simulation is a suitable method to apply theoretical principles in order to identify effective parameters in dynamic stray current influenced corrosion. Simulation techniques can be utilized for various mitigation methods applied in a small scales for selection of the most efficient method with regards to field applications. In this research, laboratory simulation of potential fluctuations caused by dynamic stray current on a cathodically protected structure was investigated. A lab model capable of generating DC static and dynamic stray currents and simulating its effects on cathodically protected samples were developed based on stray current induced (contact-less) polarization technique. Stray current pick-up and discharge spots on an influenced structure were simulated by inducing fluctuations in the sample’s stationary potential. Two mitigation methods for dynamic stray current interference on buried structures namely application of sacrificial anodes as preferred discharge point for the stray current and potentially controlled cathodic protection was investigated. Results showed that the application of sacrificial anodes can be effective in reducing interference only in discharge spot. But cathodic protection through potential controlling is more suitable for mitigating dynamic stray current effects.Keywords: simulation, dynamic stray current, fluctuating potentials, sacrificial anode
Procedia PDF Downloads 3035444 A Tomb Structure in Pursuit of Tradition in 2oth Century Turkey and Its Story; the Tomb of Haci Hâkim Kemal Onsun and His Wife
Authors: Yavuz Arat, Ugur Tuztasi, Mehmet Uysal
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Anatolia has been the host of many civilizations and a site where architectural structures of many cultural layers were interpreted. Most significantly the Turks who settled in Central Asia brought their architectural dynamics and cultural accumulation to Anatolia after the 12th century. The tomb structures first observed in Central Asia under the influence of Islamic faith and Turkish cultural heritage has blossomed under Great Seljuk Empire and with the Anatolian Seljuk Empire these tombs changed both in size and form with rich and beautiful samples from Ahlat to Sivas to Kayseri and Konya. This tomb tradition which started during 13th century has continued during the Ottoman Empire period with some alterations of form and evolved into the rarely observed mausoleum type tombs. The Ottoman tradition of building tombs inside mosque gardens and their forms present the clues of an important burial tradition. However this understanding was abandoned in 20th century Turkey. This tradition was abandoned with regard to legal regulations and health conditions. This study investigates the vestiges of this tradition and its spatial reflections over a sample. The present sample is representative of a tradition that started in 1970s and the case of building tombs inside mosque gardens will be illustrated over the tomb of Hacı Kemal Onsun and his wife which is located in Konya, the capital of the Anatolian Seljuks. The building process of this tomb will be evaluated with regard to burial traditions and architectural stylization.Keywords: tomb, language of architectural form, Anatolian Seljuk tombs, Ottoman tombs
Procedia PDF Downloads 409