Search results for: Kathy Hall
175 Two-Dimensional Van-Der Waals Heterostructure for Highly Energy-Efficient Field-Free Deterministic Spin-Orbit Torque Switching at Room Temperature
Authors: Pradeep Raj Sharma, Bogeun Jang, Jongill Hong
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Spin-orbit torque (SOT) is an efficient approach for manipulating the magnetization of ferromagnetic materials (FMs), providing improved device performance, better compatibility, and ultra-fast switching with lower power consumption compared to spin-transfer torque (STT). Among the various materials and structural designs, two-dimensional (2D) van-der Waals (vdW) layered materials and their heterostructures have been demonstrated as highly scalable and promising device architecture for SOT. In particular, a bilayer heterostructure consisting of fully 2D-vdW-FM, non-magnetic material (NM) offers a potential platform for controlling the magnetization using SOT because of the advantages of being easy to scale and less energy to switch. Here, we report filed-free deterministic switching driven by SOT at room temperature, integrating perpendicularly magnetized 2D-vdW material Fe₃GaTe₂ (FGaT) and NM WTe₂. Pulse current-induced magnetization switching with an ultra-low current density of about 6.5×10⁵ A/cm², yielding a SOT efficiency close to double-digits at 300 K, is reported. These values are two orders of magnitude higher than those observed in conventional heavy metal (HM) based SOT and exceed those reported with 2D-vdW layered materials. WTe₂, a topological semimetal possessing strong SOC and high spin Hall angle, can induce significant spin accumulation with negligible spin loss across the transparent 2D bilayer heterointerface. This promising device architecture enables highly compatible, energy-efficient, non-volatile memory and lays the foundation for designing efficient, flexible, and miniaturized spintronic devices.Keywords: spintronics, spin-orbit torque, spin Hall effect, spin Hall angle, topological semimetal, perpendicular magnetic anisotropy
Procedia PDF Downloads 13174 Use of Geometrical Relationship in the Ancient Vihara Housing Reclining Buddha Remains of Thailand's Kamphaeng Phet World Heritage Site
Authors: Vacharee Svamivastu
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This research investigates the application of geometrical relationship to the ancient religious assembly hall (Vihara) housing a reclining Buddha statue of Thailand's Kamphaeng Phet Historical Park. The study utilizes the archaeological and wooden roof structure remains of the Vihara as the prima facie evidence, supplemented with evidence from other active archaeological sites with architectural kinship as well as Buddhist ideology. At present, the wooden roofs of the Vihara fell prey to the elements and there remain only the base, columns and enclosing walls. Unlike typical Viharas whose floor plan are of rectangular shape, the floor plan of the Vihara housing the reclining Buddha is of square configuration of 25x25m. Further observation has revealed the utilization of large laterite boulders as the principal construction material of the assembly hall (Vihara) columns. The laterite columns are of square shape (1x1m) and various heights (H), ranging from 3.50m to 5.50m. The erection of the Vihara required a total of 36 laterite columns. The pattern of columns arrangement is of two rows of inner columns, two rows of outer columns and two rows of verandah columns. The space between pairs of the verandah columns was stacked with laterite blocks of varying sizes to form the Vihara walls with small openings for ventilation. Upon applying the geometrical relationship-grid system to the Vihara, the results reveal that the placement of the columns was deliberately and masterfully undertaken such that the center of the square-shaped Vihara is conspicuously spacious so as to accommodate the sacred reclining Buddha statue. The elegance of the Vihara demonstrates the ingenious application of geometrical relationship to transforming a space into a structure (i.e. Vihara) of architectural and religious significance.Keywords: geometrical relationship, the religious assembly hall, Vihara, Kamphaeng Phet School of Master Builder
Procedia PDF Downloads 277173 Improving Efficiencies of Planting Configurations on Draft Environment of Town Square: The Case Study of Taichung City Hall in Taichung, Taiwan
Authors: Yu-Wen Huang, Yi-Cheng Chiang
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With urban development, lots of buildings are built around the city. The buildings always affect the urban wind environment. The accelerative situation of wind caused of buildings often makes pedestrians uncomfortable, even causes the accidents and dangers. Factors influencing pedestrian level wind including atmospheric boundary layer, wind direction, wind velocity, planting, building volume, geometric shape of the buildings and adjacent interference effects, etc. Planting has many functions including scraping and slowing urban heat island effect, creating a good visual landscape, increasing urban green area and improve pedestrian level wind. On the other hand, urban square is an important space element supporting the entrance to buildings, city landmarks, and activity collections, etc. The appropriateness of urban square environment usually dominates its success. This research focuses on the effect of tree-planting on the wind environment of urban square. This research studied the square belt of Taichung City Hall. Taichung City Hall is a cuboid building with a large mass opening. The square belt connects the front square, the central opening and the back square. There is often wind draft on the square belt. This phenomenon decreases the activities on the squares. This research applies tree-planting to improve the wind environment and evaluate the effects of two types of planting configuration. The Computational Fluid Dynamics (CFD) simulation analysis and extensive field measurements are applied to explore the improve efficiency of planting configuration on wind environment. This research compares efficiencies of different kinds of planting configuration, including the clustering array configuration and the dispersion, and evaluates the efficiencies by the SET*.Keywords: micro-climate, wind environment, planting configuration, comfortableness, computational fluid dynamics (CFD)
Procedia PDF Downloads 311172 Understanding Co-Living Experience through University Residential Halls - A Pilot Study
Authors: Michelle W. T. Cheng, Yau Y.
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Hong Kong continues to be ranked as the least affordable housing market in the world, making co-living a feasible alternative in this high-density city. Although the number of co-living residences has increased in Hong Kong, co-living as a housing typology is still a new concept for many. Little research has been conducted on this new housing typology, let alone the co-living experience. To address this gap, this study targeted student residents in university residential halls as it is a more controlled environment (e.g., with established rules and guidelines regarding the use of communal facilitates and housing management) for studying co-living experiences in Hong Kong. To date, no research study has systematically identified anti-social behavior (ASB) in co-living spaces. Since ASB can be influenced by factors such as social norms and individual interpretation, it has an elastic definition that results in different levels of acceptance. Unlike other types of housing, co-living spaces can be potentially more influenced by the neighborhood as residents share more time and space. As a pilot study, this research targeted one university residential hall to examine student co-living experiences. To clarify, the research question is focused on identifying the social factors that impact the residential satisfaction of those who co-living in residential halls. Quantitative data (n=100) were collected via a structured questionnaire to measure the residential environment, including ASB, social neighboring, community attachment, and perceived hall management efficacy. The survey was distributed at the end of the academic year to ensure that respondents had at least one year of first-hand experience living in a co-living space. To gather qualitative data, follow-up focus group interviews were conducted with 16 participants who completed the survey. The semi-structured interviews aimed to elicit the participants' perspectives on their co-living experience. Through analyzing their co-living experiences, the researcher identified factors that affected their residential satisfaction and provided recommendations to enhance their co-living experience.Keywords: co-living, university residential hall, anti-social behabiour, neighbour relationship, community attachement
Procedia PDF Downloads 88171 Gammarus: Asellus Ratio as an Index of Organic Pollution: A Case Study in Markeaton, Kedleston Hall, and Allestree Park Lakes Derby, UK
Authors: Usman Bawa
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Macro-invertebrates have been used to monitor organic pollution in rivers and streams. Several biotic indices based on macro-invertebrates have been developed over the years including the Biological Monitoring Working Party (BMWP). A new biotic index, the Gammarus:Asellus ratio has been recently proposed as an index of organic pollution. This study tested the validity of the Gammarus:Asellus ratio as an index of organic pollution, by examining the relationship between the Gammarus:Asellus ratio and physical-chemical parameters, and other biotic indices such as BMWP and, Average Score Per Taxon (ASPT) from lakes and streams at Markeaton Park, Allestree Park, and Kedleston Hall, Derbyshire. Macro invertebrates were sampled using the standard five-minute kick sampling techniques physical and chemical environmental variables were obtained based on standard sampling techniques. Eighteen sites were sampled, six sites from Markeaton Park (three sites across the stream and three sites across the lake). Six sites each were also sampled from Allestree Park and Kedleston Hall lakes. The Gammarus:Asellus ratio showed an opposite significant positive correlations with parameters indicative of organic pollution such as the level of nitrates, phosphates, and calcium and also revealed a negatively significant correlations with other biotic indices (BMWP/ASPT). The BMWP score correlated positively significantly with some water quality parameters such as dissolved oxygen and flow rate, but revealed no correlations with other chemical environmental variables. The BMWP score was significantly higher in the stream than the lake in Markeaton Park, also The ASPT scores appear to be significantly higher in the upper Lakes than the middle and lower lakes. This study has further strengthened the use of BMWP/ASPT score as an index of organic pollution. But, additional application is required to validate the use of Gammarus:Asellus as a rapid bio monitoring tool.Keywords: Asellus, biotic index, Gammarus, macro invertebrates, organic pollution
Procedia PDF Downloads 347170 The Effects of Architectural Anatomy on Improving the Quality of Place Identity: Case Study of Shiraz Opera Hall
Authors: Hamid Reza Zeraatpisheh, Shamsoddin Hashemi, Farshad Negintaji
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This study has examined the effects of the architectural anatomy of opera hall on improving the quality of place identity. By measuring the effects of place identity on the inner aspects of human which are influenced by the physical and social environments it has investigated the results of a balance between internal and external environment. To assess the anatomical effects of urban landscape, two components of subjective landscape including perception and diversity and the component of objective landscape including form and order have been measured. The current survey is descriptive and the statistical population has been Shiraz which is a city in Iran. To analyze the data the SPSS software has been used. The results have been investigated in two levels of descriptive and inferential statistics. In the inferential statistics, Pearson correlation coefficient has been used to evaluate the research hypotheses. The results of this study indicate that between the dimensions of landscape, the component of the subjective landscape has the highest impact on the place identity and in the second place, an objective landscape has the impact on the place identity. Anatomical effects have an important role on improving the quality of place identity of Shiraz citizens and in order to enhance the place identity in the urban landscape it is also required that they will be inspired and operated.Keywords: architectural anatomy, identity, place identity, urban landscape, perception
Procedia PDF Downloads 549169 An Experimental Study of the External Thermal Insulation System’s (ETICS) Efficiency in Buildings during Spring Conditions
Authors: Carmen Viñas Arrebola, Antonio Rodriguez Sanchez, Sheila Varela Lujan, Mariano Gonzalez Cortina, Cesar Porras Amores
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The research group TEMA from the School of Building (UPM) is working in the line of energy efficiency and comfort in building. The need to reduce energy consumption in the building construction implies designing new constructive systems. These systems help to reduce both consumption and energy losses in order to achieve adequate thermal comfort for people in any type of building. In existing buildings the best option is the rehabilitation focused on thermal insulation. The aim of this paper is to design, monitor and analyze the first results of thermal behavior of the ETICS system in façades. This retrofitting solution consists of adding thermal insulation on the outside of the building, helping to create a continuous envelope on the façades. The analysis is done by comparing a rehabilitated part of the building with ETICS system and another part which has not been rehabilitated, and it is taken as reference. Both of them have the same characteristics. Temperature measurements were taken with type K thermocouples according to the previous design of the monitoring and in the same period of time. The pilot building of the study is situated in Benimamet Street, in San Cristobal de Los Ángeles, in the south of Madrid. It was built in the late 50s. The 51st entrance hall, which is restored, and the 47th entrance hall, in original conditions, have been studied.Keywords: comfort in building, energy efficiency in building, ETICS, thermal properties
Procedia PDF Downloads 316168 Phyto-Assisted Synthesis of Magnesium Oxide Nanoparticles: Characterization and Applications
Authors: Surendra Kumar Gautam, Mahesh Dhungana
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Magnesium oxide nanoparticles (MgO NPs) are less toxic to humans and the environment as compared to other metal oxide nanoparticles. Various conventional chemical and physical methods are used for synthesis whose toxicity level is high and highly expensive. As the best alternative, phyto-assisted synthesis has emerged, which uses extracts from plant parts for the synthesis of nanoparticles. Here, we report the synthesis of MgO nanoparticles with the assistance of beetroot extract and leaf extract of P. guajava and A. adenophora. The synthesized MgO NPs were characterized by X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR), and UV-visible spectroscopy. X-ray analysis for the broadening of peaks was used to evaluate the crystallite size and lattice strain using Debye-Scherer and Williamson–Hall method. The results of crystallite size obtained by both methods are in close proximity. The crystallite size obtained by the Williamson-Hall method seems more accurate, with values being 8.1 nm and 13.2 nm for beetroot MgO NPs and P. guajava MgO NPs, respectively. The FT-IR spectroscopy revealed the dominance of chemical bonds as well as functional groups on MgO NPs surfaces. The UV-visible absorption spectra of MgO NPs were found to be 310 nm, 315 nm, and 315 nm for beetroot, P. guajava, and A. adenophora leaf extract, respectively. Among the three samples, beetroot-mediated MgO NPs were effective antibacterial against both gram-positive and Gram-negative bacteria. In addition, synthesized MgO NPs also show significant antioxidant efficacy against 1,1-diphenyl-2-picrylhydrazyl radical. Further, beetroot MgO NPs showed the highest photocatalytic activity of about 91% in comparison with other samples.Keywords: MgO NPs, XRD, FTIR, antibacterial, antioxidant and photocatalytic activity
Procedia PDF Downloads 85167 Theatrical Architecture in Bologna at the Beginning of the Twentieth Century: The Renaissance of Modernissimo Cinema
Authors: Giorgia Predari, Riccardo Gulli
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The paper describes the history and the stylistic choices adopted in the construction of Palazzo Ronzani in Bologna, which was the first building to rise after the heavy demolitions carried out in the historical center of the city at the beginning of the twentieth century. In 1910, the local administration adopted a detailed plan to change the aspect of the city, as it was already happening in the main European capitals. In this context, starting from 1911, the architect and scenographer Gualtiero Pontoni designed for Alessandro Ronzani -the owner of a well-known Bolognese beer company- his Palazzo, which is listed among the first multifunctional buildings in Bologna, containing offices, commercial activities, and entertainment spaces. In an area of about 2000 m², the architect was able to propose a theatre with a capacity of 2000 seats at the basement, shops, a cafè-chantant and a restaurant on the ground floor, clubs, studios and commercial stores on the mezzanine and the first plan, and a hotel on the upper floors. The whole core of the building, at the underground levels, consisted of a reinforced concrete frame (one of the first examples of this type of construction in the city), which allowed the hall to have a free span of 11 x 12 meters, and a height of about 9 meters. Used until 2007 as a cinema, the hall has remained then in disuse for almost 10 years, but now an important functional restoration project with a strong architectural and scenographic value is taking place. It will bring the spaces back to the original geometries, in a historical and artistic condition inspired by the styles of the early Twentieth century.Keywords: Modernissimo, Palazzo Ronzani, liberty, Bologna
Procedia PDF Downloads 121166 Computed Tomography Brain and Inpatient Falls: An Audit Evaluating the Indications and Outcomes
Authors: Zain Khan, Steve Ahn, Kathy Monypenny, James Fink
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In Australian public hospitals, there were approximately 34,000 reported inpatient falls between 2015 to 2016. The gold standard for diagnosing intracranial injury is non-contrast enhanced brain computed tomography (CTB). Over a three-month timeframe, a total of one hundred and eighty (180) falls were documented between the hours of 4pm and 8am at a large metro hospital. Only three (3) of these scans demonstrated a positive intra-cranial finding. The rationale for scanning varied. The common indications included a fall with head strike, the presence of blood thinning medication, loss of consciousness, reduced Glasgow Coma Scale (GCS), vomiting and new neurological findings. There are several validated tools to aid in decision-making around ordering CTB scans in the acute setting, but no such accepted tool exists for the inpatient space. With further data collection, spanning a greater length of time and through involving multiple centres, work can be done towards generating such a tool that can be utilized for inpatient falls.Keywords: computed tomography, falls, inpatient, intracranial hemorrhage
Procedia PDF Downloads 175165 Polar Nanoregions in Lead-Free Relaxor Ceramics: Unveiling through Impedance Spectroscopy
Authors: Mohammed Mesrar, Hamza El Malki, Hamza Mesrar
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In this study, ceramics of (1-x)(Na0.5Bi0.5)TiO3 x(K0.5 Bi0.5)TiO3 were synthesized through a conventional calcination process (solid-state method) at 1000°C for 4 hours, with x(%) values ranging from 0.0 to 100. Room temperature XRD patterns confirmed the phase formation of the samples. The Rietveld refinement method was employed to verify the morphotropic phase boundary (MPB) at x(%)=16-20. We investigated the average crystallite size and lattice strain using Scherrer's formula and Williamson-Hall (W-H) analysis. SEM image analyses provided additional evidence of the impact of doping on structural growth under low temperatures. Relaxation time extracted from Z″(f) and M″(f) spectra for x(%) = 0.0, 12, 16, 20, and 30 followed the Arrhenius law, revealing the presence of three distinct relaxation mechanisms with varying activation energies. The shoulder response in M″(f) indirectly indicated the existence of highly polarizable entities in the samples, serving as a signature of polar nanoregions (PNRs) within the grains.In this study, ceramics of (1-x)(Na0.5Bi0.5)TiO3 x(K0.5 Bi0.5)TiO3 were synthesized through a conventional calcination process (solid-state method) at 1000°C for 4 hours, with x(%) values ranging from 0.0 to 100. Room temperature XRD patterns confirmed the phase formation of the samples. The Rietveld refinement method was employed to verify the morphotropic phase boundary (MPB) at x(%)=16-20. We investigated the average crystallite size and lattice strain using Scherrer's formula and Williamson-Hall (W-H) analysis. SEM image analyses provided additional evidence of the impact of doping on structural growth under low temperatures. Relaxation time extracted from Z″(f) and M″(f) spectra for x(%) = 0.0, 12, 16, 20, and 30 followed the Arrhenius law, revealing the presence of three distinct relaxation mechanisms with varying activation energies. The shoulder response in M″(f) indirectly indicated the existence of highly polarizable entities in the samples, serving as a signature of polar nanoregions (PNRs) within the grains.Keywords: (1-x)(Na0.5Bi0.5)TiO3 x(K0.5 Bi0.5)TiO3, Rietveld refinement, Scanning electron microscopy (SEM), Williamson-Hall plots, charge density distribution, dielectric properties
Procedia PDF Downloads 65164 Australian Teachers and School Leaders’ Use of Differentiated Learning Experiences as Responsive Teaching for Students with ADHD
Authors: Kathy Gibbs
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There is a paucity of research in Australia about educators’ use of differentiated instruction (DI) to support the learning of students with ADHD. This study reports on small-scale, qualitative research using interviews with teachers and school leaders to identify how they use DI as an effective teaching instruction for students with ADHD. Findings showed that teachers and school leaders have a good understanding of ADHD; teachers use DI as an effective teaching practice to enhance learning for this student group and ensure the classroom environment is safe and secure. However, they do not adjust assessments for students with ADHD. School leaders are not clear on how teachers differentiate assessments or adapt to the classroom environment. These results highlight the need for further research at the teacher and teacher-educator level teachers to ensure teaching practices are effective in reducing unwanted behaviours that prevent students with ADHD from achieving their full academic potential.Keywords: teachers, differentiated instruction, ADHD, student learning, educators knowledge
Procedia PDF Downloads 55163 A Qualitative Evidence of the Markedness of Code Switching during Commercial Bank Service Encounters in Ìbàdàn Metropolis
Authors: A. Robbin
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In a multilingual setting like Nigeria, the success of service encounters is enhanced by the use of a language that ensures the linguistic and persuasive demands of the interlocutors. This study examined motivations for code switching as a negotiation strategy in bank-hall desk service encounters in Ìbàdàn metropolis using Myers-Scotton’s exploration on markedness in language use. The data consisted of transcribed audio recording of bank-hall service encounters, and direct observation of bank interactions in two purposively sampled commercial banks in Ìbàdàn metropolis. The data was subjected to descriptive linguistic analysis using Myers Scotton’s Markedness Model. Findings reveal that code switching is frequently employed during different stages of service encounter: greeting, transaction and closing to fulfil relational, bargaining and referential functions. Bank staff and customers code switch to make unmarked, marked and explanatory choices. A strategy used to identify with customer’s cultural affiliation, close status gap, and appeal to begrudged customer; or as an explanatory choice with non-literate customers for ease of communication. Bankers select English to maintain customers’ perceptions of prestige which is retained or diverged from depending on their linguistic preference or ability. Yoruba is seen as an efficient negotiation strategy with both bankers and their customers, making choices within conversation to achieve desired conversational and functional aims.Keywords: banking, bilingualism, code-switching, markedness, service encounter
Procedia PDF Downloads 207162 Community-Based Ecotourism Development for Sustainability: Lessons From Desa Cinta Kobuni
Authors: Awangku Hassanal Bahar Pengiran Bagul, Fauziahton Ag. Samad
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The focus of this study is to outline the development of Community-Based Ecotourism (CBET) in order to achieve sustainability. The CBET in Desa Cinta Kobuni is a result of a collaboration between Kampung Kobuni, Kota Kinabalu City Hall or DBKK (Dewan Bandaraya Kota Kinabalu), and Universiti Malaysia Sabah (UMS). It is located in Inanam, a sub-district of Kota Kinabalu city. The current ecotourism activities are still in the growth stage and mainly focused on cultural tourism products and activities that showcase their traditional food, clothing, language, history, values, beliefs, dance, arts, and crafts. The study’s methodological approach is qualitative with narrative inquiry, also known as storytelling. This enables the study to access valuable insight with rich data into the complexity of developing community-based ecotourism. The results show that there are three major impacts on the Desa Cinta Kobuni, which are, 1) the increment of secondary income, 2) the advancement of women’s empowerment, and 3) the enhanced sustainability initiatives of the villagers. The experience in developing their first CBET has resulted in the Kota Kinabalu City Hall producing the Framework for Sustainable Community Based Ecotourism that integrates Sustainable Development Goals and the Global Code of Ethics for Tourism (GCET) for future CBET development in other parts of the city. The paper concludes that there is a significant positive transformation of the village and the villagers while reaffirming that Community-Based ecotourism (CBET) is a sustainable form of tourism that improves the quality of life of hosts at the tourist destination.Keywords: community, ecotourism, cultural tourism, sustainability, sustainable development
Procedia PDF Downloads 33161 The Potential and Economic Viability Analysis of Grid-Connected Solar PV Power in Kenya
Authors: Remember Samu, Kathy Kiema, Murat Fahrioglu
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This present study is aimed at minimizing the dependence on fossil fuels thus reducing greenhouse gas (GHG) emissions and also to curb for the rising energy demands in Kenya. In this analysis, 35 locations were each considered for their techno-economic potential of installation of a 10MW grid-connected PV plant. The sites are scattered across the country but are mostly concentrated in the eastern region and were selected based on their accessibility to the national grid and availability of their meteorological parameters from NASA Solar Energy Dataset. RETScreen software 4.0 version will be employed for the analysis in this present paper. The capacity factor, simple payback, equity payback, the net present value (NPV), annual life cycle savings, energy production cost, net annual greenhouse gas emission reduction and the equivalent barrels of crude oil not consumed are outlined. Energy accounting is performed and compared to the existing grid tariff for an effective feasibility argument of this 10MW grid-connected PV power system.Keywords: photovoltaics, project viability analysis, PV module, renewable energy
Procedia PDF Downloads 314160 Gap Formation into Bulk InSb Crystals Grown by the VDS Technique Revealing Enhancement in the Transport Properties
Authors: Dattatray Gadkari, Dilip Maske, Manisha Joshi, Rashmi Choudhari, Brij Mohan Arora
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The vertical directional solidification (VDS) technique has been applied to the growth of bulk InSb crystals. The concept of practical stability is applied to the case of detached bulk crystal growth on earth in a simplified design. By optimization of the set up and growth parameters, 32 ingots of 65-75 mm in length and 10-22 mm in diameter have been grown. The results indicate that the wetting angle of the melt on the ampoule wall and the pressure difference across the interface are the crucial factors effecting the meniscus shape and stability. Taking into account both heat transfer and capillarity, it is demonstrated that the process is stable in case of convex menisci (seen from melt), provided that pressure fluctuations remain in a stable range. During the crystal growth process, it is necessary to keep a relationship between the rate of the difference pressure controls and the solidification to maintain the width of gas gap. It is concluded that practical stability gives valuable knowledge of the dynamics and could be usefully applied to other crystal growth processes, especially those involving capillary shaping. Optoelectronic properties were investigated in relation to the type of solidification attached and detached ingots growth. These samples, room temperature physical properties such as Hall mobility, FTIR, Raman spectroscopy and microhardness achieved for antimonide samples grown by VDS technique have shown the highest values gained till at this time. These results reveal that these crystals can be used to produce InSb with high mobility for device applications.Keywords: alloys, electronic materials, semiconductors, crystal growth, solidification, etching, optical microscopy, crystal structure, defects, Hall effect
Procedia PDF Downloads 419159 Safety Culture, Mindfulness and Safe Behaviours of Students Residing in the Halls of Residence of Obafemi Awolowo University, Ile Ife, Nigeria
Authors: Olajumoke Adetoun Ojeleye
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The study assessed the safety culture, mindfulness and safe behaviors of students residing in the halls of residence of Obafemi Awolowo University (OAU), Ile Ife, Nigeria. The objectives of the study were to assess the level of safety mindfulness of students residing in the halls of residence of OAU, examine their safety culture and establish whether these students are involved in unsafe practices. The study employed a cross-sectional research design and instrument used for data collection was a self-structured, self-administered questionnaire. The questionnaire was tested for validity and reliability with its reliability coefficient at 0.71 before being used for data collection. Respondents were selected by multi-stage sampling technique and the sample size was 530. Data collection took 2 weeks and analysed using descriptive statistical techniques. Results showed that about half of the respondents’ population (49.8%) was between the ages of 20-24 years. There were more males (56.2%) than females (43.8%). Although data demonstrated that majority (91.7%) of the respondents are highly safety minded and the safety culture of an equally high proportion (83.4%) was adjudged fair, a lot of improvement is needed in the area of alerting or informing management of impending dangers and studying the hall handbook to internalize its contents. The study further showed that only 43.6% of respondents had good safety practices and behaviors and majority (56.4%) had fair safety practices and behaviors. One accidental discovery of the study is the finding that not a few of the students squat their counterparts. The study recommended the establishment of clearly written out complaint procedure that is accessible and available to all hall residents, building more hostels with adequate facilities to address the issue of overcrowding and also putting systems in place in order to encourage residents to report incidences/accidents.Keywords: safe behaviours, safety culture, safety mindfulness, student
Procedia PDF Downloads 264158 Transducers for Measuring Displacements of Rotating Blades in Turbomachines
Authors: Pavel Prochazka
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The study deals with transducers for measuring vibration displacements of rotating blade tips in turbomachines. In order to prevent major accidents with extensive economic consequences, it shows an urgent need for every low-pressure steam turbine stage being equipped with modern non-contact measuring system providing information on blade loading, damage and residual lifetime under operation. The requirement of measuring vibration and static characteristics of steam turbine blades, therefore, calls for the development and operational verification of both new types of sensors and measuring principles and methods. The task is really demanding: to measure displacements of blade tips with a resolution of the order of 10 μm by speeds up to 750 m/s, humidity 100% and temperatures up to 200 °C. While in gas turbines are used primarily capacitive and optical transducers, these transducers cannot be used in steam turbines. The reason is moisture vapor, droplets of condensing water and dirt, which disable the function of sensors. Therefore, the most feasible approach was to focus on research of electromagnetic sensors featuring promising characteristics for given blade materials in a steam environment. Following types of sensors have been developed and both experimentally and theoretically studied in the Institute of Thermodynamics, Academy of Sciences of the Czech Republic: eddy-current, Hall effect, inductive and magnetoresistive. Eddy-current transducers demand a small distance of 1 to 2 mm and change properties in the harsh environment of steam turbines. Hall effect sensors have relatively low sensitivity, high values of offset, drift, and especially noise. Induction sensors do not require any supply current and have a simple construction. The magnitude of the sensors output voltage is dependent on the velocity of the measured body and concurrently on the varying magnetic induction, and they cannot be used statically. Magnetoresistive sensors are formed by magnetoresistors arranged into a Wheatstone bridge. Supplying the sensor from a current source provides better linearity. The MR sensors can be used permanently for temperatures up to 200 °C at lower values of the supply current of about 1 mA. The frequency range of 0 to 300 kHz is by an order higher comparing to the Hall effect and induction sensors. The frequency band starts at zero frequency, which is very important because the sensors can be calibrated statically. The MR sensors feature high sensitivity and low noise. The symmetry of the bridge arrangement leads to a high common mode rejection ratio and suppressing disturbances, which is important, especially in industrial applications. The MR sensors feature high sensitivity, high common mode rejection ratio, and low noise, which is important, especially in industrial applications. Magnetoresistive transducers provide a range of excellent properties indicating their priority for displacement measurements of rotating blades in turbomachines.Keywords: turbines, blade vibration, blade tip timing, non-contact sensors, magnetoresistive sensors
Procedia PDF Downloads 129157 A Technical and Economic Feasibility Study of the Use of Concentrating Solar Power (CSP) in Desalination Plants on the Kenyan Coast
Authors: Kathy Mwende Kiema, Remember Samu, Murat Fahrioglu
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Despite the implementation of a Feed in Tariff (FiT) for solar power plants in Kenya, the uptake and subsequent development of utility scale power plants has been slow. This paper, therefore, proposes a Concentrating Solar Power (CSP) plant configuration that can supply both power to the grid and operate a sea water desalination plant, thus providing an economically viable alternative to Independent Power Producers (IPPs). The largest city on the coast, Mombasa, has a chronic water shortage and authorities are looking to employ desalination plants to supply a deficit of up to 100 million cubic meters of fresh water per day. In this study the desalination plant technology was selected based on an analysis of operational costs in $/m3 of plants that are already running. The output of the proposed CSP plant, Net Present Value (NPV), plant capacity factor, thermal efficiency and quantity of CO2 emission avoided were simulated using Greenius software (Green energy system analysis tool) developed by the institute of solar research at the German Aerospace Center (DLR). Data on solar irradiance were derived from the Solar and Wind Energy Resource Assessment (SWERA) for Kenya.Keywords: desalination, feed in tariff, independent power producer, solar CSP
Procedia PDF Downloads 285156 Cognitive Stereotype Behaviors and Their Imprinting on the Individuals with Autism
Authors: Li-Ju Chen, Hsiang-Lin Chan, Hsin-Yi Kathy Cheng, Hui-Ju Chen
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Stereotype behavior is one of the maladaptive syndromes of the individuals with autism. Most of the previous researches focused on the stereotype behavior with stimulating type, while less on the stereotype behavior about cognition (This research names it cognitive stereotype behavior; CSB). This research explored CSB and the rationality to explain CSB with imprinting phenomenon. After excluding the samples without CSB described, the data that came from 271 individuals with autism were recruited and analyzed with quantitative and qualitative analyses. This research discovers that : (1) Most of the individuals with autism originally came out CSB at 3 years old and more than a half of them appeared before 4 years old; The average age which firstly came out CSB was 6.10 years old, the average time insisting or ossifying CSB was 31.71 minutes each time and the average longest time which they last was 358.35 minutes (5.97 hours). (2) CSB demonstrates various aspects, this research classified them into 4 fields with 26 categories. They were categorized into sudden CSB or habitual CSB by imprinting performance. (3) Most of the autism commented that their CSBs were not necessary but they could not control them well. One-third of them appeared CSB suddenly and the first occurrence accompanied a strong emotional or behavioral response. (4) Whether respondent is the person with autism himself/herself or not was the critical element: on the awareness of the severity degree, disturbance degree, and the emotional /behavioral intensity at the first-time CSB happened. This study concludes imprinting could reasonably explain the phenomenon CSB forms. There are implications leading the individuals with autism and their family to develop coping strategies to promote individuals with autism having a better learning accomplishment and life quality in their future.Keywords: autism, cognitive stereotype behavior, constructivism, imprinting, stereotype
Procedia PDF Downloads 131155 Techno-Economic Comparative Analysis of Grid Connected Solar Photovoltaic (PV) to Solar Concentrated Solar Power (CSP) for Developing Countries: A Case Study of Kenya and Zimbabwe
Authors: Kathy Mwende Kiema, Remember Samu, Murat Fahrioglu
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The potential of power generation from solar resources has been established as being robust in sub Saharan Africa. Consequently many governments in the region have encouraged the exploitation of this resource through, inter alia direct funding, subsidies and legislation (such as feed in tariffs). Through a case study of Kenya and Zimbabwe it is illustrated that a good deal of proposed grid connected solar power projects and related feed in tariffs have failed to take into account key economic and technical considerations in the selection of solar technologies to be implemented. This paper therefore presents a comparison between concentrated solar power (CSP) and solar photovoltaic (PV) to assess which technology is better suited to meet the energy demand for a given set of prevailing conditions. The evaluation criteria employed is levelized cost of electricity (LCOE), net present value (NPV) and plant capacity factor. The outcome is therefore a guide to aid policy makers and project developers in choosing between CSP and PV given certain solar irradiance values, planned nominal plant capacity, availability of water resource and a consideration of whether or not the power plant is intended to compete with existing technologies, primarily fossil fuel powered, in meeting the peak load.load.Keywords: capacity factor, peak load, solar PV, solar CSP
Procedia PDF Downloads 287154 An Automatic Large Classroom Attendance Conceptual Model Using Face Counting
Authors: Sirajdin Olagoke Adeshina, Haidi Ibrahim, Akeem Salawu
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large lecture theatres cannot be covered by a single camera but rather by a multicamera setup because of their size, shape, and seating arrangements. Although, classroom capture is achievable through a single camera. Therefore, a design and implementation of a multicamera setup for a large lecture hall were considered. Researchers have shown emphasis on the impact of class attendance taken on the academic performance of students. However, the traditional method of carrying out this exercise is below standard, especially for large lecture theatres, because of the student population, the time required, sophistication, exhaustiveness, and manipulative influence. An automated large classroom attendance system is, therefore, imperative. The common approach in this system is face detection and recognition, where known student faces are captured and stored for recognition purposes. This approach will require constant face database updates due to constant changes in the facial features. Alternatively, face counting can be performed by cropping the localized faces on the video or image into a folder and then count them. This research aims to develop a face localization-based approach to detect student faces in classroom images captured using a multicamera setup. A selected Haar-like feature cascade face detector trained with an asymmetric goal to minimize the False Rejection Rate (FRR) relative to the False Acceptance Rate (FAR) was applied on Raspberry Pi 4B. A relationship between the two factors (FRR and FAR) was established using a constant (λ) as a trade-off between the two factors for automatic adjustment during training. An evaluation of the proposed approach and the conventional AdaBoost on classroom datasets shows an improvement of 8% TPR (output result of low FRR) and 7% minimization of the FRR. The average learning speed of the proposed approach was improved with 1.19s execution time per image compared to 2.38s of the improved AdaBoost. Consequently, the proposed approach achieved 97% TPR with an overhead constraint time of 22.9s compared to 46.7s of the improved Adaboost when evaluated on images obtained from a large lecture hall (DK5) USM.Keywords: automatic attendance, face detection, haar-like cascade, manual attendance
Procedia PDF Downloads 73153 Barriers and Facilitators to Inclusive Programming for Children with Mental and/or Developmental Challenges: A Participatory Action Research of Perspectives from Families and Professionals
Authors: Minnie Y. Teng, Kathy Xie, Jarus Tal
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Rationale: The traditional approach to community programs for children with mental and/or developmental challenges often involves segregation from typically-developing peers. However, studies show that inclusive education improves children’s quality of life, self-concept, and long term health outcomes. Investigating factors that influence inclusion can thus have important implications in the design and facilitation of community programs such that all children - across a spectrum of needs and abilities - may benefit. Objectives: This study explores barriers and facilitators to inclusive community programming for children aged 0 to 12 with developmental/mental challenges. Methods: Using a participatory-action research methodology, semi-structured focus groups and interviews will be used to explore perspectives of sighted students, instructors, and staff. Data will be transcribed and coded thematically. Practice Implications or Results: By having a deeper understanding of the barriers and facilitators to inclusive programming in the community, researchers can work with the broader community to facilitate inclusion in children’s community programs. Conclusions: Expanding inclusive practices may improve the health and wellbeing of the pediatric populations with disabilities, which consistently reports lower levels of participation. These findings may help to identify gaps in existing practices and ways to approach them.Keywords: aquatic programs, children, disabilities, inclusion, community programs
Procedia PDF Downloads 116152 A Hardware-in-the-loop Simulation for the Development of Advanced Control System Design for a Spinal Joint Wear Simulator
Authors: Kaushikk Iyer, Richard M Hall, David Keeling
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Hardware-in-the-loop (HIL) simulation is an advanced technique for developing and testing complex real-time control systems. This paper presents the benefits of HIL simulation and how it can be implemented and used effectively to develop, test, and validate advanced control algorithms used in a spinal joint Wear simulator for the Tribological testing of spinal disc prostheses. spinal wear simulator is technologically the most advanced machine currently employed For the in-vitro testing of newly developed spinal Discimplants. However, the existing control techniques, such as a simple position control Does not allow the simulator to test non-sinusoidal waveforms. Thus, there is a need for better and advanced control methods that can be developed and tested Rigorouslybut safely before deploying it into the real simulator. A benchtop HILsetupis was created for experimentation, controller verification, and validation purposes, allowing different control strategies to be tested rapidly in a safe environment. The HIL simulation aspect in this setup attempts to replicate similar spinal motion and loading conditions. The spinal joint wear simulator containsa four-Barlinkpowered by electromechanical actuators. LabVIEW software is used to design a kinematic model of the spinal wear Simulator to Validatehow each link contributes towards the final motion of the implant under test. As a result, the implant articulates with an angular motion specified in the international standards, ISO-18192-1, that define fixed, simplified, and sinusoid motion and load profiles for wear testing of cervical disc implants. Using a PID controller, a velocity-based position control algorithm was developed to interface with the benchtop setup that performs HIL simulation. In addition to PID, a fuzzy logic controller (FLC) was also developed that acts as a supervisory controller. FLC provides intelligence to the PID controller by By automatically tuning the controller for profiles that vary in amplitude, shape, and frequency. This combination of the fuzzy-PID controller is novel to the wear testing application for spinal simulators and demonstrated superior performance against PIDwhen tested for a spectrum of frequency. Kaushikk Iyer is a Ph.D. Student at the University of Leeds and an employee at Key Engineering Solutions, Leeds, United Kingdom, (e-mail: [email protected], phone: +44 740 541 5502). Richard M Hall is with the University of Leeds, the United Kingdom as a professor in the Mechanical Engineering Department (e-mail: [email protected]). David Keeling is the managing director of Key Engineering Solutions, Leeds, United Kingdom (e-mail: [email protected]). Results obtained are successfully validated against the load and motion tolerances specified by the ISO18192-1 standard and fall within limits, that is, ±0.5° at the maxima and minima of the motion and ±2 % of the complete cycle for phasing. The simulation results prove the efficacy of the test setup using HIL simulation to verify and validate the accuracy and robustness of the prospective controller before its deployment into the spinal wear simulator. This method of testing controllers enables a wide range of possibilities to test advanced control algorithms that can potentially test even profiles of patients performing various dailyliving activities.Keywords: Fuzzy-PID controller, hardware-in-the-loop (HIL), real-time simulation, spinal wear simulator
Procedia PDF Downloads 172151 Study of the Nanostructured Fe₅₀Cr₃₅Ni₁₅ Powder Alloy Developed by Mechanical Alloying
Authors: Salim Triaa, Fella Kali-Ali
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Nanostructured Fe₅₀Cr3₃₅Ni₁₅ alloys were prepared from pure elemental powders using high energy mechanical alloying. The mixture powders obtained are characterized by several techniques. X-ray diffraction analysis revelated the formation of the Fe₁Cr₁ compound with BBC structure after one hour of milling. A second compound Fe₃Ni₂ with FCC structure was observed after 12 hours of milling. The size of crystallite determined by Williamson Hall method was about 5.1 nm after 48h of mill. SEM observations confirmed the growth of crushed particles as a function of milling time, while the homogenization of our powders into different constituent elements was verified by the EDX analysis.Keywords: Fe-Cr-Ni alloy, mechanical alloying, nanostructure, SEM, XRD
Procedia PDF Downloads 176150 Predicting Halal Food Consumption for Muslim Turkish Immigrants Living in Germany
Authors: Elif Eroglu Hall, Nurdan Sevim
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The purposes of this research are to clarify the determinants of Muslim immigrants in consuming halal food by using components of Theory of Planned Behavior. The study was done by surveying Turkish immigrants living in Cologne Germany. The results of this study show that the intentions of Muslim Turkish immigrants in consuming halal food is influenced by attitude, subjective norms and perceived behavioral control.Keywords: halal food, immigrants, religion, theory of planned behavior
Procedia PDF Downloads 296149 Development of Monitoring Blood Bank Center Based PIC Microcontroller Using CAN Communication
Authors: Kaiwan S. Ismael, Ergun Ercelebi, Majeed Nader
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This paper describes the design and implementation of a hardware setup for online monitoring of 24 refrigerators inside blood bank center using the microcontroller and CAN bus for communications between each node. Due to the security of locations in the blood bank hall and difficulty of monitoring of each refrigerator separately, this work proposes a solution to monitor all the blood bank refrigerators in one location. CAN-bus system is used because it has many applications and advantages, especially for this system due to easy in use, low cost, providing a reduction in wiring, fast to repair and easily expanding the project without a problem.Keywords: control area network (CAN), monitoring blood bank center, PIC microcontroller, MPLAB IDE
Procedia PDF Downloads 486148 Evaluating Cognition and Movement Coordination of Adolescents with Intellectual Disabilities through Ball Games
Authors: Wann-Yun Shieh, Hsin-Yi Kathy Cheng, Yan-Ying Ju, Yu-Chun Yu, Ya-Cheng Shieh
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Adolescents who have intellectual disabilities often demonstrate maladaptive behaviors in their daily activities due to either physical abnormalities or neurological disorders. These adolescents commonly struggle with their cognition and movement coordination when it comes to executing tasks such as throwing or catching objects smoothly, quickly, and gracefully, in contrast to their typically developing peers. Simply measuring movement time and distance doesn't provide a comprehensive view of their performance challenges. In this study, a ball-playing approach was proposed to assess the cognition and movement coordination of adolescents with intellectual disabilities using a smart ball equipped with an embedded inertial sensor. Four distinct ball games were specifically designed for this smart ball: two focusing on lower limb activities (dribbling along a straight line and navigating a zigzag path) and two centered around upper limb tasks (picking up and throwing and catching the ball). The cognition and movement coordination of 25 adolescents with intellectual disabilities (average age 18.36 ± 2.46 years) with that of 25 typically developing adolescents (average age 18.36 ± 0.49 years) were compared in these four tests. The results clearly revealed significant differences in the cognition and movement coordination between the adolescents with intellectual disabilities and the typically developing adolescents. These differences encompassed aspects such as movement speed, hand-eye coordination, and control over objects across all the tests conducted.Keywords: cognition, intellectual disabilities, movement coordination, smart ball
Procedia PDF Downloads 75147 Limited Ventilation Efficacy of Prehospital I-Gel Insertion in Out-of-Hospital Cardiac Arrest Patients
Authors: Eunhye Cho, Hyuk-Hoon Kim, Sieun Lee, Minjung Kathy Chae
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Introduction: I-gel is a commonly used supraglottic advanced airway device in prehospital out-of-hospital cardiac arrest (OHCA) allowing for minimal interruption of continuous chest compression. However, previous studies have shown that prehospital supraglottic airway had inferior neurologic outcomes and survival compared to no advanced prehospital airway with conventional bag mask ventilation. We hypothesize that continuous compression with i-gel as an advanced airway may cause insufficient ventilation compared to 30:2 chest compression with conventional BVM. Therefore, we investigated the ventilation efficacy of i-gel with the initial arterial blood gas analysis in OHCA patients visiting our ER. Material and Method: Demographics, arrest parameters including i-gel insertion, initial arterial blood gas analysis was retrospectively analysed for 119 transported OHCA patients that visited our ER. Linear regression was done to investigate the association with i-gel insertion and initial pCO2 as a surrogate of prehospital ventilation. Result: A total of 52 patients were analysed for the study. Of the patients who visited the ER during OHCA, 24 patients had i-gel insertion and 28 patients had BVM as airway management in the prehospital phase. Prehospital i-gel insertion was associated with the initial pCO2 level (B coefficient 29.9, SE 10.1, p<0.01) after adjusting for bystander CPR, cardiogenic cause of arrest, EMS call to arrival. Conclusion: Despite many limitations to the study, prehospital insertion of i-gel was associated with high initial pCO2 values in OHCA patients visiting our ER, possibly indicating insufficient ventilation with prehospital i-gel as an advanced airway and continuous chest compressions.Keywords: arrest, I-gel, prehospital, ventilation
Procedia PDF Downloads 335146 Non-Universality in Barkhausen Noise Signatures of Thin Iron Films
Authors: Arnab Roy, P. S. Anil Kumar
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We discuss angle dependent changes to the Barkhausen noise signatures of thin epitaxial Fe films upon altering the angle of the applied field. We observe a sub-critical to critical phase transition in the hysteresis loop of the sample upon increasing the out-of-plane component of the applied field. The observations are discussed in the light of simulations of a 2D Gaussian Random Field Ising Model with references to a reducible form of the Random Anisotropy Ising Model.Keywords: Barkhausen noise, Planar Hall effect, Random Field Ising Model, Random Anisotropy Ising Model
Procedia PDF Downloads 390