Search results for: core length
2612 Physical and Mechanical Characterization of Limestone in the Quarry of Meftah (Algeria)
Authors: Khaled Benyounes
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Determination of the rock mechanical properties such as unconfined compressive strength UCS, Young’s modulus E, and tensile strength by the Brazilian test Rtb is considered to be the most important component in drilling and mining engineering project. Research related to establishing correlation between strength and physical parameters of rocks has always been of interest to mining and reservoir engineering. For this, many rock blocks of limestone were collected from the quarry located in Meftah (Algeria), the cores were crafted in the laboratory using a core drill. This work examines the relationships between mechanical properties and some physical properties of limestone. Many empirical equations are established between UCS and physical properties of limestone (such as dry bulk density, velocity of P-waves, dynamic Young’s modulus, alteration index, and total porosity). Other correlations, UCS - tensile strength, dynamic Young’s modulus - static Young’s modulus have been find. Based on the Mohr-Coulomb failure criterion, we were able to establish mathematical relationships that will allow estimating the cohesion and internal friction angle from UCS and indirect tensile strength. Results from this study can be useful for mining industry for resolve range of geomechanical problems such as slope stability.Keywords: limestone, mechanical strength, Young’s modulus, porosity
Procedia PDF Downloads 6352611 Carl Schmitt in the Age of Immanence: A Critical Reading
Authors: Manuel Iretzberger
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This paper aims to uncover the ideological aspects in the political thought of Carl Schmitt, who is enjoying an ever-increasing popularity in various academic fields, following in the wake of rising interest in questions of sovereignty and legitimacy. Given Schmitt’s biography, i.e. his role as the ‘Crown Jurist of the Third Reich’ (Gurian), an extraordinarily thorough examination is necessary; however, instead of merely ‘deconstructing’ his works, certain ontological truths he might have attained, shall be taken seriously. To this end, his notions of politics and the state of exception are scrutinized, which are indeed considered intriguing, yet prove to be enigmatic and impalpable at the core when read closely. In order to explain this conjuncture, both Schmitt’s philosophy of history and his ‘secret discussion’ (Agamben) with Walter Benjamin are depicted. As it turns out – it is argued – his concept of the Political has to be conceived of as embedded in a much broader context: In a post-transcendental, immanent age, he regards traditional modes of representation as no longer feasible and clings to authoritarianism as a surrogate – his Catholicism plays a decisive role here, forcing him to inject normatively biased assumptions into his political writings. Seeing Schmitt perform ‘rearguard action’ not only serves to disarm his work of most of its menacing aura, it also allows drawing conclusions about ways of legitimatizing democratic rule in modern times, as the paper tries to outline in its last section.Keywords: Benjamin, history, immanence, Schmitt, sovereignty
Procedia PDF Downloads 2912610 PSS®E Based Modelling, Simulation and Synchronous Interconnection of Eastern Grid and North-Eastern Regional Grid of India
Authors: Toushik Maiti, Saibal Chatterjee, Kamaljyoti Gogoi, Arijit Basuray
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Eastern Regional(ER) Grid and North Eastern Regional (NER) Grid are two major grids of Eastern Part of India. Both of the grid consists of voltage level 765kV, 400 kV, 220 kV and numerous buses at lower voltage range. Eastern Regional Grid and North Eastern Regional Grid are not only connected among themselves but are also connected to various other grids of India. ER and NER Grid having various HVDC lines or back to back systems which form the total network. The studied system comprises of 340 buses of different voltage levels and transmission lines running over a length of 32089 km. The validation of load flow has been done using IEEE STANDARD 30 bus system. The power flow simulation analysis has been performed after synchronizing both the Eastern Grid and North-Eastern Regional Grid of India using Power System Simulators for Engineering (PSS®E) Important inferences has been drawn from the study.Keywords: HVDC, load flow, PSS®E, unsymmetrical and symmetrical faults
Procedia PDF Downloads 3812609 Micro-Oscillator: Passive Production and Manipulation of Microdrops
Authors: Khelfaoui Rachid, Chekifi Tawfiq, Dennai Brahim, Maazouzi A. Hak
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A numerical and experimental studies of passive micro drops production have been presented. This paper focuses on the modeling of micro-oscillators systems which are composed by passive amplifier without moving part. The micro-system modeling is based on geometrical oscillators form. An asymmetric micro-oscillator design that is based on a bistable fluidic amplifier is proposed. The characteristic size of the channels is generally about 35 microns of depth. The numerical results indicate that the production and manipulation of microdrops are possible with passive device within a typical oscillators chamber of 2.25 mm diameter and 0.20 mm length when the Reynolds number is Re = 490. The novel micro drops method that is presented in this study provides a simple solution about the production of microdrops problems in micro system. We undertake an experimental step. The first part is based on the realisation of sample oscillator; the second part is consisted of visualization, production and manipulation of microdrops.Keywords: modelling, miscible, micro drops, production, oscillator sample, capillary
Procedia PDF Downloads 3772608 Enhancing the Efficiency of Organic Solar Cells Using Metallic Nanoparticles
Authors: Sankara Rao Gollu, Ramakant Sharma, G. Srinivas, Souvik Kundu, Dipti Gupta
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In recent years, bulk heterojunction organic solar cells (BHJ OSCs) based on polymer–fullerene attracted a large research attention due to their numerous advantages such as light weight, easy processability, eco-friendly, low-cost, and capability for large area roll-to-roll manufacturing. BHJ OSCs usually suffer from insufficient light absorption due to restriction on keeping thin ( < 150 nm) photoactive layer because of small exciton diffusion length ( ~ 10 nm) and low charge carrier mobilities. It is thus highly desirable that light absorption as well as charge transport properties are enhanced by alternative methods so as to improve the device efficiency. In this work, therefore, we have focused on the strategy of incorporating metallic nanostructures in the active layer or charge transport layer to enhance the absorption and improve the charge transport.Keywords: organic solar cell, efficiency, bulk heterojunction, polymer-fullerene
Procedia PDF Downloads 3962607 Lateral Heterogeneity of 1/Q in Eastern and Southeastern Anatolia
Authors: Ufuk Aydın
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The Coda attenuation and frequency dependency of seismic wave are strongly dependent on the effective stresses structures within the upper crust. In this study, the data of three different stations were used to examine the lateral variation of stress. The tectonic structures of these three areas have been examined comparatively using lateral coda tomography. In the study using the single scatter method, the window length selected to be 20 second. Coda values 80 with 94 and frequency dependency values obtained between 0.69 and 1.21. The 1/QC values for the three regions ranged from 0.0012 to 0.017, highlighting the regional differences in the seismotectonic activity of the crust. The lowest absorption values obtained from Erzurum station when the highest absorption values obtained at the Kemaliye station. The low Qc and high frequency dependency values obtained Kemaliye, which indicates that it has highest tectonic activity than other two regions. The seismo-dynamics data obtained from the study found to be in agreement with the tectonic structure of the region.Keywords: regional coda attenuation, tectonic stress, crustal deformation
Procedia PDF Downloads 1822606 Resistive Instability in a Multi Ions Hall Thrusters Plasma
Authors: Sukhmander Singh
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Hall thrusters are preferred over chemical thrusters because of its high exhaust velocity (around 10 times higher) and high specific impulse. The propellant Xenon is ionized inside the channel and controlled by the magnetic field. The strength of the magnetic field is such that only electrons get magnetized and ions remain unmagnetized because of larger Larmor radius as compared with the length of the channel of the device. There is quite a possibility of the existence of multi ions in a Hall thruster plasma because of dust contribution or another process which take place in the chamber. In this paper, we have derived the dispersion relation for multi ions resistive instability in a hall plasma. The analytical approach is also used to find out the propagating speed and the growth rate of the instability. In addition, some growing waves are also found to exist in the plasma. The dispersion relation is solved numerically to see the behavior of the instability with the plasma parameters viz, the temperature of plasma species, wave number, drift velocity, collision frequency, magnetic field.Keywords: instability, resisitive, thrusters, waves
Procedia PDF Downloads 3112605 Settlement Performance of Soft Clay Reinforced with Granular Columns
Authors: Muneerah Jeludin, V. Sivakumar
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Numerous laboratory-based research studies on the behavior of ground improved with granular columns with respect to bearing capacity have been well-documented. However, information on its settlement performance is still scarce. Laboratory model study on the settlement behavior of soft clay reinforced with granular columns was conducted and results are presented. The investigation uses a soft kaolin clay sample of 300 mm in diameter and 400 mm in length. The clay samples were reinforced with single and multiple granular columns of various lengths using the displacement and replacement installation method. The results indicated that that no settlement reduction was achieved for a short single floating column. The settlement reduction factors reported for L/d ratios of 5.0, 7.5 and 10.0 are in the range of 1 to 2. The findings obtained in this research showed that the reduction factors are considerably less and that load-sharing mechanism between columns and surrounding clay is complex, particularly for column groups and is affected by other factors such as negative skin friction.Keywords: ground improvement, model test, reinforced soil, settlement
Procedia PDF Downloads 4632604 The Role of P2X7 Cytoplasmic Anchor in Inflammation
Authors: Federico Cevoli
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Purinergic P2X7 receptors (P2X7R) are ligand-gated non-selective cation channels involved in several physiological and pathological processes. They are particularly promising pharmacological targets as they are present in an increasing number of different cells types. P2X7R activation is triggered following elevated concentrations of extracellular ATP, similarly to those observed in tissues injury, chronic inflammation and T-cell activation, as well as in the scrambling of phospholipids leading to membrane blebbing and apoptosis. Another hallmark of P2X7 is cell permeabilization, commonly known as “macropore” formation allowing the passage of nanometer-sized molecules up to 900Da. Recently, full-length P2X7 Cryo-EM structures revealed unique functional sites, including two cytoplasmic domains - the cytoplasmic "anchor" and "ballast". To date, the molecular units/complex by which P2X7R exerts its pathophysiological functions are unknown. Using custom-made cell-penetrating HIV-1 TAT peptides, we show for the first-time potential implications of P2X7 cytoplasmic anchor in the regulation of caspase3/7 activation as well as TNFα regulation.Keywords: P2X7R, immunology, TAT-peptide, cell death
Procedia PDF Downloads 1332603 Etude 3D Quantum Numerical Simulation of Performance in the HEMT
Authors: A. Boursali, A. Guen-Bouazza
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We present a simulation of a HEMT (high electron mobility transistor) structure with and without a field plate. We extract the device characteristics through the analysis of DC, AC and high frequency regimes, as shown in this paper. This work demonstrates the optimal device with a gate length of 15 nm, InAlN/GaN heterostructure and field plate structure, making it superior to modern HEMTs when compared with otherwise equivalent devices. This improves the ability to bear the burden of the current density passes in the channel. We have demonstrated an excellent current density, as high as 2.05 A/m, a peak extrinsic transconductance of 0.59S/m at VDS=2 V, and cutting frequency cutoffs of 638 GHz in the first HEMT and 463 GHz for Field plate HEMT., maximum frequency of 1.7 THz, maximum efficiency of 73%, maximum breakdown voltage of 400 V, leakage current density IFuite=1 x 10-26 A, DIBL=33.52 mV/V and an ON/OFF current density ratio higher than 1 x 1010. These values were determined through the simulation by deriving genetic and Monte Carlo algorithms that optimize the design and the future of this technology.Keywords: HEMT, silvaco, field plate, genetic algorithm, quantum
Procedia PDF Downloads 3482602 Optimum Design of Tall Tube-Type Building: An Approach to Structural Height Premium
Authors: Ali Kheyroddin, Niloufar Mashhadiali, Frazaneh Kheyroddin
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In last decades, tubular systems employed for tall buildings were efficient structural systems. However, increasing the height of a building leads to an increase in structural material corresponding to the loads imposed by lateral loads. Based on this approach, new structural systems are emerging to provide strength and stiffness with the minimum premium for height. In this research, selected tube-type structural systems such as framed tubes, braced tubes, diagrids and hexagrid systems were applied as a single tube, tubular structures combined with braced core and outrigger trusses on a set of 48, 72, and 96-story, respectively, to improve integrated structural systems. This paper investigated structural material consumption by model structures focusing on the premium for height. Compared analytical results indicated that as the height of the building increased, combination of the structural systems caused the framed tube, hexagrid and braced tube system to pay fewer premiums to material tonnage while in diagrid system, combining the structural system reduced insignificantly the steel material consumption.Keywords: braced tube, diagrid, framed tube, hexagrid
Procedia PDF Downloads 2872601 Efficient Pre-Concentration of As (III) Using Guanidine-Modified Magnetic Mesoporous Silica in the Food Sample
Authors: Majede Modheji, Hamid Emadi, Hossein Vojoudi
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An efficient magnetic mesoporous structure was designed and prepared for the facile pre-concentration of As(III) ions. To prepare the sorbent, a core-shell magnetic silica nanoparticle was covered by MCM-41 like structure, and then the surface was modified by guanidine via an amine linker. The prepared adsorbent was investigated as an effective and sensitive material for the adsorption of arsenic ions from the aqueous solution applying a normal batch method. The imperative variables of the adsorption were studied to increase efficiency. The dynamic and static processes were tested that matched a pseudo-second order of kinetic model and the Langmuir isotherm model, respectively. The sorbent reusability was investigated, and it was confirmed that the designed product could be applied at best for six cycles successively without any significant efficiency loss. The synthesized product was tested to determine and pre-concentrate trace amounts of arsenic ions in rice and natural waters as a real sample. A desorption process applying 5 mL of hydrochloric acid (0.5 mol L⁻¹) as an eluent exhibited about 98% recovery of the As(III) ions adsorbed on the GA-MSMP sorbent.Keywords: arsenic, adsorption, mesoporous, surface modification, MCM-41
Procedia PDF Downloads 1462600 Culture and Health Equity: Unpacking the Sociocultural Determinants of Eye Health for Indigenous Australian Diabetics
Authors: Aryati Yashadhana, Ted Fields Jnr., Wendy Fernando, Kelvin Brown, Godfrey Blitner, Francis Hayes, Ruby Stanley, Brian Donnelly, Bridgette Jerrard, Anthea Burnett, Anthony B. Zwi
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Indigenous Australians experience some of the worst health outcomes globally, with life expectancy being significantly poorer than those of non-Indigenous Australians. This is largely attributed to preventable diseases such as diabetes (prevalence 39% in Indigenous Australian adults > 55 years), which is attributed to a raised risk of diabetic visual impairment and cataract among Indigenous adults. Our study aims to explore the interface between structural and sociocultural determinants and human agency, in order to understand how they impact (1) accessibility of eye health and chronic disease services and (2) the potential for Indigenous patients to achieve positive clinical eye health outcomes. We used Participatory Action Research methods, and aimed to privilege the voices of Indigenous people through community collaboration. Semi-structured interviews (n=82) and patient focus groups (n=8) were conducted by Indigenous Community-Based Researchers (CBRs) with diabetic Indigenous adults (> 40 years) in four remote communities in Australia. Interviews (n=25) and focus groups (n=4) with primary health care clinicians in each community were also conducted. Data were audio recorded, transcribed verbatim, and analysed thematically using grounded theory, comparative analysis and Nvivo 10. Preliminary analysis occurred in tandem with data collection to determine theoretical saturation. The principal investigator (AY) led analysis sessions with CBRs, fostering cultural and contextual appropriateness to interpreting responses, knowledge exchange and capacity building. Identified themes were conceptualised into three spheres of influence: structural (health services, government), sociocultural (Indigenous cultural values, distrust of the health system, ongoing effects of colonialism and dispossession) and individual (health beliefs/perceptions, patient phenomenology). Permeating these spheres of influence were three core determinants: economic disadvantage, health literacy/education, and cultural marginalisation. These core determinants affected accessibility of services, and the potential for patients to achieve positive clinical outcomes at every level of care (primary, secondary, tertiary). Our findings highlight the clinical realities of institutionalised and structural inequities, illustrated through the lived experiences of Indigenous patients and primary care clinicians in the four sampled communities. The complex determinants surrounding inequity in health for Indigenous Australians, are entrenched through a longstanding experience of cultural discrimination and ostracism. Secure and long term funding of Aboriginal Community Controlled Health Services will be valuable, but are insufficient to address issues of inequity. Rather, working collaboratively with communities to build trust, and identify needs and solutions at the grassroots level, while leveraging community voices to drive change at the systemic/policy level are recommended.Keywords: indigenous, Australia, culture, public health, eye health, diabetes, social determinants of health, sociology, anthropology, health equity, aboriginal and Torres strait islander, primary care
Procedia PDF Downloads 3002599 Optimization of Urea Water Solution Injector for NH3 Uniformity Improvement in Urea-SCR System
Authors: Kyoungwoo Park, Gil Dong Kim, Seong Joon Moon, Ho Kil Lee
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The Urea-SCR is one of the most efficient technologies to reduce NOx emissions in diesel engines. In the present work, the computational prediction of internal flow and spray characteristics in the Urea-SCR system was carried out by using 3D-CFD simulation to evaluate NH3 uniformity index (NH3 UI) and its activation time according to the official New European Driving Cycle (NEDC). The number of nozzle and its diameter, two types of injection directions, and penetration length were chosen as the design variables. The optimal solutions were obtained by coupling the CFD analysis with Taguchi method. The L16 orthogonal array and small-the-better characteristics of the Taguchi method were used, and the optimal values were confirmed to be valid with 95% confidence and 5% significance level through analysis of variance (ANOVA). The results show that the optimal solutions for the NH3 UI and activation time (NH3 UI 0.22) are obtained by 0.41 and 0,125 second, respectively, and their values are improved by 85.0% and 10.7%, respectively, compared with those of the base model.Keywords: computational fluid dynamics, NH3 uniformity index, optimization, Taguchi method, Urea-SCR system, UWS injector
Procedia PDF Downloads 2652598 A Study of the Trade-off Energy Consumption-Performance-Schedulability for DVFS Multicore Systems
Authors: Jalil Boudjadar
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Dynamic Voltage and Frequency Scaling (DVFS) multicore platforms are promising execution platforms that enable high computational performance, less energy consumption and flexibility in scheduling the system processes. However, the resulting interleaving and memory interference together with per-core frequency tuning make real-time guarantees hard to be delivered. Besides, energy consumption represents a strong constraint for the deployment of such systems on energy-limited settings. Identifying the system configurations that would achieve a high performance and consume less energy while guaranteeing the system schedulability is a complex task in the design of modern embedded systems. This work studies the trade-off between energy consumption, cores utilization and memory bottleneck and their impact on the schedulability of DVFS multicore time-critical systems with a hierarchy of shared memories. We build a model-based framework using Parametrized Timed Automata of UPPAAL to analyze the mutual impact of performance, energy consumption and schedulability of DVFS multicore systems, and demonstrate the trade-off on an actual case study.Keywords: time-critical systems, multicore systems, schedulability analysis, energy consumption, performance analysis
Procedia PDF Downloads 1072597 Effect of Different Diesel Fuels on Formation of the Cavitation Phenomena
Authors: Mohammadreza Nezamirad, Sepideh Amirahmadian, Nasim Sabetpour, Azadeh Yazdi, Amirmasoud Hamedi
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Cavitation inside the diesel injector nozzle is investigated numerically in this study. Reynolds Stress Navier Stokes set of equations (RANS) are utilized to investigate flow behavior inside the nozzle numerically. Moreover, K-ε turbulent model is found to be a better approach comparing to K-ω turbulent model. Winklhofer rectangular shape nozzle is also simulated in order to verify the current numerical scheme, and with, mass flow rate approach, the current solution is verified. Afterward, a six-hole real-size nozzle was simulated, and it was found that among different fuels used in this study with the same condition, diesel fuel provides the largest length of cavitation. Also, it was found that at the same boundary condition, RME fuel leads to the highest value of discharge coefficient and mass flow rate.Keywords: cavitation, diesel fuel, CFD, real size nozzle, discharge coefficient
Procedia PDF Downloads 1582596 Unraveling the Enigma of Military Coups through the Lens of State Fragility: A Qualitative Exploration of the Malian and Burkinabe Case
Authors: Deretha Bester
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This article explores the recent military coups in Mali (August 2020) and Burkina Faso (January 2022), utilizing qualitative case study analyses to examine the pre-coup domestic contextual conditions that precipitated the events. By framing the research through the conceptual lens of state fragility, the research identifies key political, economic, and societal factors that converge to create an environment conducive for coups to occur. From the analyses, the study discusses several patterns that emerged, all revealing the significance of the core functions of governance. Through an in-depth exploration that brings the state back into the coup debate, the study provides rich insights into the complex dynamics of military intervention in political affairs, highlighting the urgency of understanding the underlying domestic factors that can lead to radical political changes. By illuminating these intricate dynamics, the article seeks to provide detailed insights needed to fully understand the challenges moulding the region's political terrain.Keywords: governance failures, military coups, political dynamics, Sahel region, state fragility
Procedia PDF Downloads 632595 Food Traceability for Small and Medium Enterprises Using Blockchain Technology
Authors: Amit Kohli, Pooja Lekhi, Gihan Adel Amin Hafez
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Blockchain is a distributor ledger technology trend that extended to different fields and proved a remarkable success. Blockchain technology is a vital proliferation technique that recuperates the food supply chain traceability process. While tracing is the core of the food supply chain; still, a complex system mitigates the exceptional risk of food contamination, foodborne, food waste, and food fraud. In addition, the upsurge of food supply chain data variance and variety in the traceability system requires complete transparency, a secure, steadfast, sustainable, and efficient approach to face the food supply chain challenges. On the other hand, blockchain technical aspects merged with a detailed implementation plan, the advantages and challenges in food traceability have not been much elucidated for small and medium enterprises (SMEs.) This paper demonstrated the advantages and challenges of applying blockchain in SMEs combined with the success stories of firms implementing blockchain to cover the gap. Moreover, blockchain architecture in SMEs and how technology, organization, and environment frameworks can guarantee the success of blockchain implementation have been revealed.Keywords: blockchain technology, small and medium enterprises, food traceability, blockchain architecture
Procedia PDF Downloads 1872594 3D Quantum Simulation of a HEMT Device Performance
Authors: Z. Kourdi, B. Bouazza, M. Khaouani, A. Guen-Bouazza, Z. Djennati, A. Boursali
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We present a simulation of a HEMT (high electron mobility transistor) structure with and without a field plate. We extract the device characteristics through the analysis of DC, AC and high frequency regimes, as shown in this paper. This work demonstrates the optimal device with a gate length of 15 nm, InAlN/GaN heterostructure and field plate structure, making it superior to modern HEMTs when compared with otherwise equivalent devices. This improves the ability to bear the burden of the current density passes in the channel. We have demonstrated an excellent current density, as high as 2.05 A/mm, a peak extrinsic transconductance of 590 mS/mm at VDS=2 V, and cutting frequency cutoffs of 638 GHz in the first HEMT and 463 GHz for Field plate HEMT., maximum frequency of 1.7 THz, maximum efficiency of 73%, maximum breakdown voltage of 400 V, DIBL=33.52 mV/V and an ON/OFF current density ratio higher than 1 x 1010. These values were determined through the simulation by deriving genetic and Monte Carlo algorithms that optimize the design and the future of this technology.Keywords: HEMT, Silvaco, field plate, genetic algorithm, quantum
Procedia PDF Downloads 4752593 A Site Unexplored: Recently Discovered In Bangladesh
Authors: Md. Rifat-Ur- Rahman
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Dhamairnagar, Sirajganj, Bangladesh, local villagers describe the peculiar mounds spotted scattered among the nearby villages as “Buruj”. Among these, a mound was explored in one of these mounds, in Khirtala village, in early 2019. Primary archaeological surveys and map making has been conducted in this site, where suspect lays the remains of an 8 square miles city, at least 1200 years old. In the government gazettes of Bangladesh from 1990, this place has been linked with a mythical kind from the Indian epic, Mahabharata. In the primary explorations, found bricks, mortars, different kinds of potteries and terracotta pieces. Assumable observation is that this city was a flourishing establishment during the early Pala dynasty of Bengal (800 AD to 1200 AD). At present there are four indigenous groups live around this site and they are known as Mahato, Teli, Oraon and Santals. These four indigenous groups are considered as the core four of Bengali ethnicity. In the folklore of these groups we find stories of ancient kingdoms which have not been documented through archaeological findings yet. So, a question rises about the population that was used to reside in this archaeological site. Were they the ancestors of these indigenous tribes that are dwelling in this area? With such primary information, the aim is to conduct a comparative study of the physiology; osteology and cultural practices of this civilization.Keywords: Archaeology, Heritage, Indigenous Peoples, Physiology
Procedia PDF Downloads 1342592 A Crystal Plasticity Approach to Model Dynamic Strain Aging
Authors: Burak Bal, Demircan Canadinc
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Dynamic strain aging (DSA), resulting from the reorientation of C-Mn clusters in the core of dislocations, can provide a strain hardening mechanism. In addition, in Hadfield steel, negative strain rate sensitivity is observed due to the DSA. In our study, we incorporated dynamic strain aging onto crystal plasticity computations to predict the local instabilities and corresponding negative strain rate sensitivity. Specifically, the material response of Hadfield steel was obtained from monotonic and strain-rate jump experiments under tensile loading. The strain rate range was adjusted from 10⁻⁴ to 10⁻¹s ⁻¹. The crystal plasticity modeling of the material response was carried out based on Voce-type hardening law and corresponding Voce hardening parameters were determined. The solute pinning effect of carbon atom was incorporated to crystal plasticity simulations at microscale level by computing the shear stress contribution imposed on an arrested dislocation by carbon atom. After crystal plasticity simulations with modifying hardening rule, which takes into account the contribution of DSA, it was seen that the model successfully predicts both the role of DSA and corresponding strain rate sensitivity.Keywords: crystal plasticity, dynamic strain aging, Hadfield steel, negative strain rate sensitivity
Procedia PDF Downloads 2582591 Mechanical Behavior of CFTR Column Joint under Pull out Testing
Authors: Nasruddin Junus
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CFTR column is one of the improvements CFT columns by inserting reinforcing steel bars into infill concrete. The presence of inserting reinforcing steel bars is increasing the excellent structural performance of the CFT column, especially on the fire-resisting performance. Investigation on the mechanical behavior of CFTR column connection is summarized in the three parts; column to column joint, column to beam connection, and column base. Experiment that reported in this paper is concerned on the mechanical behavior of CFTR column joint under pull out testing, especially on its stress transfer mechanism. A number series of the pull out test on the CFT with inserting reinforcing steel bar are conducted. Ten test specimens are designed, constructed, and tested to examine experimentally the effect of the size of square steel tube, size of the bearing plate, length of embedment steel bars, kind of steel bars, and the numbers of rib plate.Keywords: CFTR column, pull out, stress, transfer mechanism
Procedia PDF Downloads 2882590 Each One, Reach One: Peer Mentoring Support for Faculty Women of Color
Authors: Teresa Leary Handy
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As awareness of the importance of diversity has increased in society, higher education has also begun to recognize the importance of supporting faculty of color. In the university setting, faculty women of color specifically encounter barriers that impact their level of job satisfaction, retention rates, and pedagogical practices. These barriers and challenges not only undermine faculty diversity efforts but also hinder the ability of colleges and universities to provide a supportive environment that fosters students' academic success and sense of belonging. Faculty who are marginalized and on the periphery in higher education institutions need support so that they can feel confident in building a student’s sense of belonging which can impact a student’s academic success and goal of earning a college degree. This study examined and sought to understand the importance of supporting faculty of color, specifically women faculty of color, and how this type of faculty support can impact student academic success and a student’s sense of belonging. The study furthered original research on strategies to move an institution forward on the equity spectrum to support belonging and inclusions as core culture elements.Keywords: equity, inclusion, belonging, women, faculty support
Procedia PDF Downloads 662589 Diabatic Flow of Sub-Cooled R-600a Inside a Capillary Tube: Concentric Configuration
Authors: Ravi Kumar, Santhosh Kumar Dubba
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This paper presents an experimental study of a diabatic flow of R-600a through a concentric configured capillary tube suction line heat exchanger. The details of experimental facility for testing the diabatic capillary tube with different inlet sub-cooling degree and pressure are discussed. The effect of coil diameter, capillary length, capillary tube diameter, sub-cooling degree and inlet pressure on mass flow rate are presented. The degree of sub-cooling at the inlet of capillary tube is varied from 3-20°C. The refrigerant mass flow rate is scattered up with rising of pressure. A semi-empirical correlation to predict the mass flow rate of R-600a flowing through a diabatic capillary tube is proposed for sub-cooled inlet conditions. The proposed correlation predicts measured data with an error band of ±20 percent.Keywords: diabatic, capillary tube, concentric, R-600a
Procedia PDF Downloads 2032588 DEM Simulation of the Formation of Seed Granules in Twin-Screw Granulation Process
Authors: Tony Bediako Arthur, Nejat Rahmanian, Nana Gyan Sekyi
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The possibility of producing seeded granules from fine and course powders is a major challenge as the control parameters that affect its producibility is still under investigation. The seeded granulation is a novel form of producing granules where the granule is made up of larger particles at the core, which are surrounded by fine particles. The possibility of managing granulation through course particle feed rate control makes seeded granulation in continuous granulation useful in terms of process control. Twin screw granulation is now a major process of choice for the wet continuous granulation process in the industry. It is, therefore, imperative to investigate the process control parameters that influence the formation of seeded granules in twin screw granulation. In this paper, the effect of the twin screws rotating speed on the production of seeded granules has been examined. Pictorial and quantitative analysis indicates a high number of seeded granules forming at low screw rotating speeds. It is also instructive to say that higher tensile stress occurs at the kneading section of the screws; thus, higher rotating speed courses the fines for breaking off from the seed particle.Keywords: DEM, twin-screw, Seeded granules, Simulation
Procedia PDF Downloads 862587 Immunization-Data-Quality in Public Health Facilities in the Pastoralist Communities: A Comparative Study Evidence from Afar and Somali Regional States, Ethiopia
Authors: Melaku Tsehay
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The Consortium of Christian Relief and Development Associations (CCRDA), and the CORE Group Polio Partners (CGPP) Secretariat have been working with Global Alliance for Vac-cines and Immunization (GAVI) to improve the immunization data quality in Afar and Somali Regional States. The main aim of this study was to compare the quality of immunization data before and after the above interventions in health facilities in the pastoralist communities in Ethiopia. To this end, a comparative-cross-sectional study was conducted on 51 health facilities. The baseline data was collected in May 2019, while the end line data in August 2021. The WHO data quality self-assessment tool (DQS) was used to collect data. A significant improvment was seen in the accuracy of the pentavalent vaccine (PT)1 (p = 0.012) data at the health posts (HP), while PT3 (p = 0.010), and Measles (p = 0.020) at the health centers (HC). Besides, a highly sig-nificant improvment was observed in the accuracy of tetanus toxoid (TT)2 data at HP (p < 0.001). The level of over- or under-reporting was found to be < 8%, at the HP, and < 10% at the HC for PT3. The data completeness was also increased from 72.09% to 88.89% at the HC. Nearly 74% of the health facilities timely reported their respective immunization data, which is much better than the baseline (7.1%) (p < 0.001). These findings may provide some hints for the policies and pro-grams targetting on improving immunization data qaulity in the pastoralist communities.Keywords: data quality, immunization, verification factor, pastoralist region
Procedia PDF Downloads 1212586 New Vision of 'Social Europe': Renationalising the Integration Process in the Internal Market of the European Union
Authors: Robert Grzeszczak, Magdalena Gniadzik
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The article deals with one of the most significant issues concerning the functioning of the internal market of the European Union – the free movement of workers and free movement of persons. The purpose is to identify the political and legal effects of the “renationalisation process” on the EU and its Member States. The concept of renationalisation is expressed through Member States’ aim to verify the relationship with the EU. The tendency is more visible in the public opinion of several MS’s of the ‘EU core’ and may be confirmed by the changes applied by the regulatory body. The thesis for the article is the return of renationalisation tendencies in the area of the Single Market, which is supported by, among others, an open criticism of the foundations of EU integration or considerations on withdrawal from the EU by some MS. This analysis will focus primarily on the effects that renationalisation may have on the free movement of persons. The free movement of persons is one of the key issues for the development of the European integration. It is still subject to theoretical reflections, new doubts and practical issues. The latest developments in politics, law and jurisprudence demonstrate the need to reflect on the attempts to redefine certain principles regarding migrant EU workers and their protection against nationality-based discrimination.Keywords: European Union, Singel Market, free movement of persons, posting of workers
Procedia PDF Downloads 2292585 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 1702584 Recovery of an Area Degraded by Gullies in the Municipality of Monte Alto (SP), Brazil
Authors: Layane Sara Vieira, Paulo Egidio Bernardo, Roberto Saverio Souza Costa
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Anthropogenic occupations and agricultural explorations without concern for the preservation and sustainability of the activity result in soil degradation that can make rural activity unfeasible. The objective of this work was to characterize and evaluate the recovery costs of an area degraded by major erosion (gully) in the municipality of Monte Alto (SP). Topographic characterization was carried out by means of a planialtimetric survey with a total station. The contours of the gully, internal area, slope height, contribution area, volume, and costs of operations for the recovery of the gully were delimited. The results obtained showed that the gully has a length of 145.56 m, a maximum width of 36.61 m, and a gap of 19.48 m. The external area of the gully is 1,039.8741 m², and the internal area is 119.3470 m². The calculated volume was 3,282.63 m³. The intervention area for breaking slopes was measured at 8,471.29 m², requiring the construction of 19 terraces in this area, vertically spaced at 2.8 m. The estimated costs for mechanical recovery of the gully were R$ 19,167.84 (US$ 3.657,98).Keywords: erosion, volumetric assessment, soil degradation, terraces
Procedia PDF Downloads 1062583 Older Consumer’s Willingness to Trust Social Media Advertising: A Case of Australian Social Media Users
Authors: Simon J. Wilde, David M. Herold, Michael J. Bryant
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Social media networks have become the hotbed for advertising activities due mainly to their increasing consumer/user base and, secondly, owing to the ability of marketers to accurately measure ad exposure and consumer-based insights on such networks. More than half of the world’s population (4.8 billion) now uses social media (60%), with 150 million new users having come online within the last 12 months (to June 2022). As the use of social media networks by users grows, key business strategies used for interacting with these potential customers have matured, especially social media advertising. Unlike other traditional media outlets, social media advertising is highly interactive and digital channel specific. Social media advertisements are clearly targetable, providing marketers with an extremely powerful marketing tool. Yet despite the measurable benefits afforded to businesses engaged in social media advertising, recent controversies (such as the relationship between Facebook and Cambridge Analytica in 2018) have only heightened the role trust and privacy play within these social media networks. Using a web-based quantitative survey instrument, survey participants were recruited via a reputable online panel survey site. Respondents to the survey represented social media users from all states and territories within Australia. Completed responses were received from a total of 258 social media users. Survey respondents represented all core age demographic groupings, including Gen Z/Millennials (18-45 years = 60.5% of respondents) and Gen X/Boomers (46-66+ years = 39.5% of respondents). An adapted ADTRUST scale, using a 20 item 7-point Likert scale, measured trust in social media advertising. The ADTRUST scale has been shown to be a valid measure of trust in advertising within traditional media, such as broadcast media and print media, and, more recently, the Internet (as a broader platform). The adapted scale was validated through exploratory factor analysis (EFA), resulting in a three-factor solution. These three factors were named reliability, usefulness and affect, and the willingness to rely on. Factor scores (weighted measures) were then calculated for these factors. Factor scores are estimates of the scores survey participants would have received on each of the factors had they been measured directly, with the following results recorded (Reliability = 4.68/7; Usefulness and Affect = 4.53/7; and Willingness to Rely On = 3.94/7). Further statistical analysis (independent samples t-test) determined the difference in factor scores between the factors when age (Gen Z/Millennials vs. Gen X/Boomers) was utilized as the independent, categorical variable. The results showed the difference in mean scores across all three factors to be statistically significant (p<0.05) for these two core age groupings: (1) Gen Z/Millennials Reliability = 4.90/7 vs. Gen X/Boomers Reliability = 4.34/7; (2) Gen Z/Millennials Usefulness and Affect = 4.85/7 vs Gen X/Boomers Usefulness and Affect = 4.05/7; and (3) Gen Z/Millennials Willingness to Rely On = 4.53/7 vs Gen X/Boomers Willingness to Rely On = 3.03/7. The results clearly indicate that older social media users lack trust in the quality of information conveyed in social media ads when compared to younger, more social media-savvy consumers. This is especially evident with respect to Factor 3 (Willingness to Rely On), whose underlying variables reflect one’s behavioral intent to act based on the information conveyed in advertising. These findings can be useful to marketers, advertisers, and brand managers in that the results highlight a critical need to design ‘authentic’ advertisements on social media sites to better connect with these older users in an attempt to foster positive behavioral responses from within this large demographic group – whose engagement with social media sites continues to increase year on year.Keywords: social media advertising, trust, older consumers, internet studies
Procedia PDF Downloads 37