Search results for: critical cylindrical effect
19072 Reformulation of Theory of Critical Distances to Predict the Strength of Notched Plain Concrete Beams under Quasi Static Loading
Authors: Radhika V., J. M. Chandra Kishen
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The theory of critical distances (TCD), due to its appealing characteristics, has been successfully used in the past to predict the strength of brittle as well as ductile materials, weakened by the presence of stress risers under both static and fatigue loading. By utilising most of the TCD's unique features, this paper summarises an attempt for a reformulation of the point method of the TCD to predict the strength of notched plain concrete beams under mode I quasi-static loading. A zone of micro cracks, which is responsible for the non-linearity of concrete, is taken into account considering the concept of an effective elastic crack. An attempt is also made to correlate the value of the material characteristic length required for the application of TCD with the maximum aggregate size in the concrete mix, eliminating the need for any extensive experimentation prior to the application of TCD. The devised reformulation and the proposed power law based relationship is found to yield satisfactory predictions for static strength of notched plain concrete beams, with geometric dimensions of the beam, tensile strength, and maximum aggregate size of the concrete mix being the only needed input parameters.Keywords: characteristic length, effective elastic crack, inherent material strength, modeI loading, theory of critical distances
Procedia PDF Downloads 9819071 Sociolinguistic and Critical Discourse Analysis of Nigerian Proverbs: The Differences between the Representation of the Genders
Authors: Crescentia Ugwuona
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Considering the importance of proverbs in socio-cultural life through socialization in any given society, it is deemed important for people to understand the hidden meanings that proverbs may convey. So far, there has been hardly any systematic research in the representation of different genders in Nigeria. Although there are writings on the representation of women in Nigerian proverbs, they are based on the writers’ introspection. Beyond that, investigators often tend to overlook the representations of men in proverbs. This study therefore explores from the perspective of sociolinguistics and critical discourse analysis (CDA) how different genders (men and women) are represented in Nigerian proverbs with particular reference to Igbo-Nigerians; with the aim of uncovering hidden gender inequalities that exist in them. The analysis reveals that Igbo proverbs consistently perpetuate an ideology of gender inequality, that is, male proverbs depict male achievements, power, bravery, and male supremacy; while that of female connotes their submissions to cultural and traditional female domestic roles, chastity, less competent, and women subjugation. The study alerts to how gendered language in proverbs can reflect, create, and sustain gender inequality in societies; and contributes to an education aimed at gender equality, emancipator practice of appropriate language in proverbs, respect for human rights; and of the need to develop strategies for addressing the problem.Keywords: critical discourse analysis, gender representation, gender stereotypes, Igbo-Nigerian, sociolinguistics analysis, proverbs
Procedia PDF Downloads 27719070 A Non-Invasive Blood Glucose Monitoring System Using near-Infrared Spectroscopy with Remote Data Logging
Authors: Bodhayan Nandi, Shubhajit Roy Chowdhury
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This paper presents the development of a portable blood glucose monitoring device based on Near-Infrared Spectroscopy. The system supports Internet connectivity through WiFi and uploads the time series data of glucose concentration of patients to a server. In addition, the server is given sufficient intelligence to predict the future pathophysiological state of a patient given the current and past pathophysiological data. This will enable to prognosticate the approaching critical condition of the patient much before the critical condition actually occurs.The server hosts web applications to allow authorized users to monitor the data remotely.Keywords: non invasive, blood glucose concentration, microcontroller, IoT, application server, database server
Procedia PDF Downloads 22119069 Theoretical Prediction on the Lifetime of Sessile Evaporating Droplet in Blade Cooling
Authors: Yang Shen, Yongpan Cheng, Jinliang Xu
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The effective blade cooling is of great significance for improving the performance of turbine. The mist cooling emerges as the promising way compared with the transitional single-phase cooling. In the mist cooling, the injected droplet will evaporate rapidly, and cool down the blade surface due to the absorbed latent heat, hence the lifetime for evaporating droplet becomes critical for design of cooling passages for the blade. So far there have been extensive studies on the droplet evaporation, but usually the isothermal model is applied for most of the studies. Actually the surface cooling effect can affect the droplet evaporation greatly, it can prolong the droplet evaporation lifetime significantly. In our study, a new theoretical model for sessile droplet evaporation with surface cooling effect is built up in toroidal coordinate. Three evaporation modes are analyzed during the evaporation lifetime, include “Constant Contact Radius”(CCR) mode、“Constant Contact Angle”(CCA) mode and “stick-slip”(SS) mode. The dimensionless number E0 is introduced to indicate the strength of the evaporative cooling, it is defined based on the thermal properties of the liquid and the atmosphere. Our model can predict accurately the lifetime of evaporation by validating with available experimental data. Then the temporal variation of droplet volume, contact angle and contact radius are presented under CCR, CCA and SS mode, the following conclusions are obtained. 1) The larger the dimensionless number E0, the longer the lifetime of three evaporation cases is; 2) The droplet volume over time still follows “2/3 power law” in the CCA mode, as in the isothermal model without the cooling effect; 3) In the “SS” mode, the large transition contact angle can reduce the evaporation time in CCR mode, and increase the time in CCA mode, the overall lifetime will be increased; 4) The correction factor for predicting instantaneous volume of the droplet is derived to predict the droplet life time accurately. These findings may be of great significance to explore the dynamics and heat transfer of sessile droplet evaporation.Keywords: blade cooling, droplet evaporation, lifetime, theoretical analysis
Procedia PDF Downloads 14219068 The Effect of Institutions on Economic Growth: An Analysis Based on Bayesian Panel Data Estimation
Authors: Mohammad Anwar, Shah Waliullah
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This study investigated panel data regression models. This paper used Bayesian and classical methods to study the impact of institutions on economic growth from data (1990-2014), especially in developing countries. Under the classical and Bayesian methodology, the two-panel data models were estimated, which are common effects and fixed effects. For the Bayesian approach, the prior information is used in this paper, and normal gamma prior is used for the panel data models. The analysis was done through WinBUGS14 software. The estimated results of the study showed that panel data models are valid models in Bayesian methodology. In the Bayesian approach, the effects of all independent variables were positively and significantly affected by the dependent variables. Based on the standard errors of all models, we must say that the fixed effect model is the best model in the Bayesian estimation of panel data models. Also, it was proved that the fixed effect model has the lowest value of standard error, as compared to other models.Keywords: Bayesian approach, common effect, fixed effect, random effect, Dynamic Random Effect Model
Procedia PDF Downloads 6819067 Effect of Wind Braces to Earthquake Resistance of Steel Structures
Authors: H. Gokdemir
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All structures are subject to vertical and lateral loads. Under these loads, structures make deformations and deformation values of structural elements mustn't exceed their capacity for structural stability. Especially, lateral loads cause critical deformations because of their random directions and magnitudes. Wind load is one of the lateral loads which can act in any direction and any magnitude. Although wind has nearly no effect on reinforced concrete structures, it must be considered for steel structures, roof systems and slender structures like minarets. Therefore, every structure must be able to resist wind loads acting parallel and perpendicular to any side. One of the effective methods for resisting lateral loads is assembling cross steel elements between columns which are called as wind bracing. These cross elements increases lateral rigidity of a structure and prevent exceeding of deformation capacity of the structural system. So, this means cross elements are also effective in resisting earthquake loads too. In this paper; Effects of wind bracing to earthquake resistance of structures are studied. Structure models (with and without wind bracing) are generated and these models are solved under both earthquake and wind loads with different seismic zone parameters. It is concluded by the calculations that; in low-seismic risk zones, wind bracing can easily resist earthquake loads and no additional reinforcement for earthquake loads is necessary. Similarly; in high-seismic risk zones, earthquake cross elements resist wind loads too.Keywords: wind bracings, earthquake, steel structures, vertical and lateral loads
Procedia PDF Downloads 47019066 Ferromagnetic Potts Models with Multi Site Interaction
Authors: Nir Schreiber, Reuven Cohen, Simi Haber
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The Potts model has been widely explored in the literature for the last few decades. While many analytical and numerical results concern with the traditional two site interaction model in various geometries and dimensions, little is yet known about models where more than two spins simultaneously interact. We consider a ferromagnetic four site interaction Potts model on the square lattice (FFPS), where the four spins reside in the corners of an elementary square. Each spin can take an integer value 1,2,...,q. We write the partition function as a sum over clusters consisting of monochromatic faces. When the number of faces becomes large, tracing out spin configurations is equivalent to enumerating large lattice animals. It is known that the asymptotic number of animals with k faces is governed by λᵏ, with λ ≈ 4.0626. Based on this observation, systems with q < 4 and q > 4 exhibit a second and first order phase transitions, respectively. The transition nature of the q = 4 case is borderline. For any q, a critical giant component (GC) is formed. In the finite order case, GC is simple, while it is fractal when the transition is continuous. Using simple equilibrium arguments, we obtain a (zero order) bound on the transition point. It is claimed that this bound should apply for other lattices as well. Next, taking into account higher order sites contributions, the critical bound becomes tighter. Moreover, for q > 4, if corrections due to contributions from small clusters are negligible in the thermodynamic limit, the improved bound should be exact. The improved bound is used to relate the critical point to the finite correlation length. Our analytical predictions are confirmed by an extensive numerical study of FFPS, using the Wang-Landau method. In particular, the q=4 marginal case is supported by a very ambiguous pseudo-critical finite size behavior.Keywords: entropic sampling, lattice animals, phase transitions, Potts model
Procedia PDF Downloads 16019065 Cyclic Response of Reinforced Concrete Beam-Column Joint Strengthening by FRP
Authors: N. Attari, S. Amziane, M. Chemrouk
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A large number of old buildings have been identified as having potentially critical detailing to resist earthquakes. The main reinforcement of lap-spliced columns just above the joint region, discontinuous bottom beam reinforcement, and little or no joint transverse reinforcement are the most critical details of interior beam column joints in such buildings. This structural type constitutes a large share of the building stock, both in developed and developing countries, and hence it represents a substantial exposure. Direct observation of damaged structures, following the Algiers 2003 earthquake, has shown that damage occurs usually at the beam-column joints, with failure in bending or shear, depending on geometry and reinforcement distribution and type. While substantial literature exists for the design of concrete frame joints to withstand this type of failure, after the earthquake many structures were classified as slightly damaged and, being uneconomic to replace them, at least in the short term, suitable means of repairs of the beam column joint area are being studied. Furthermore; there exists a large number of buildings that need retrofitting of the joints before the next earthquake. The paper reports the results of the experimental programme, constituted of three beam-column reinforced concrete joints at a scale of one to three (1/3) tested under the effect of a pre-stressing axial load acting over the column. The beams were subjected at their ends to an alternate cyclic loading under displacement control to simulate a seismic action. Strain and cracking fields were monitored with the help a digital recording camera. Following the analysis of the results, a comparison can be made between the performances in terms of ductility, strength and mode of failure of the different strengthening solution considered.Keywords: fibre reinforced polymers, joints, reinforced concrete, beam columns
Procedia PDF Downloads 41719064 Effect of Select Surfactants on Activities of Soil Enzymes Involved in Nutrient Cycling
Authors: Frieda Eivazi, Nikita L. Mullings
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Soils are recipient for surfactants in herbicide formulations. Surfactants entering the soil environment can possibly disrupt different chemical, physical and biological interactions. Therefore, it is critical that we understand the fate, behavior and transport of surfactants upon entering the soil. A comprehensive study was conducted to examine effect of surfactants on nutrient uptake, microbial community, and enzyme activity. The research was conducted in the greenhouse growing corn (Zea mays) as a test plant in a factorial experiment (three surfactants at two different rates with control, and three herbicides) organized as randomized blocked design. Surfactants evaluated were Activator 90, Agri-Dex, and Thrust; herbicides were glyphosate, atrazine, and bentazon. Treatments examined were surfactant only, herbicide only, and surfactant + herbicide combinations. Corn was planted in fertilized soils (silt loam and silty clay) with moisture content maintained at the field capacity for optimum growth. This paper will report results of above mentioned treatments on acid phosphatase, beta-glucosidase, arylsulfatase, beta-glucosaminidase, and dehydrogenase activities. In general, there were variations in the enzyme activities with some inhibition and some being enhanced by the treatments. Activator 90 appeared to have the highest inhibitory effect on enzymatic activities. Atrazine application significantly decreased the activities of acid phosphatase, beta-glucosidase, and dehydrogenase in both soils; however, combination of Atrazine + Agridex increased the acid phosphatase activity while significantly inhibiting the other enzyme activities in soils. It was concluded that long-term field studies are needed to validate changes in nutrient uptake, microbial community and enzyme activities due to surfactant-herbicide combination effects.Keywords: herbicides, nutrient cycling, soil enzymes, surfactant
Procedia PDF Downloads 25119063 Instability by Weak Precession of the Flow in a Rapidly Rotating Sphere
Authors: S. Kida
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We consider the flow of an incompressible viscous fluid in a precessing sphere whose spin and precession axes are orthogonal to each other. The flow is characterized by two non-dimensional parameters, the Reynolds number Re and the Poincare number Po. For which values of (Re, Po) will the flow approach a steady state from an arbitrary initial condition? To answer it we are searching the instability boundary of the steady states in the whole (Re, Po) plane. Here, we focus the rapidly rotating and weakly precessing limit, i.e., Re >> 1 and Po << 1. The steady flow was obtained by the asymptotic expansion for small ε=Po Re¹/² << 1. The flow exhibits nearly a solid-body rotation in the whole sphere except for a thin boundary layer which develops over the sphere surface. The thickness of this boundary layer is of O(δ), where δ=Re⁻¹/², except where two circular critical bands of thickness of O(δ⁴/⁵) and of width of O(δ²/⁵) which are located away from the spin axis by about 60°. We perform the linear stability analysis of the steady flow. We assume that the disturbances are localized in the critical bands and make an expansion analysis in terms of ε to derive the eigenvalue problem for the growth rate of the disturbance, which is solved numerically. As the solution, we obtain an asymptote of the stability boundary as Po=28.36Re⁻⁰.⁸. This agrees excellently with the corresponding laboratory experiments and numerical simulations. One of the most popular instability mechanisms so far is the parametric instability, which turns out, however, not to give the correct stability boundary. The present instability is different from the parametric instability.Keywords: boundary layer, critical band, instability, precessing sphere
Procedia PDF Downloads 15419062 Modeling of Ductile Fracture Using Stress-Modified Critical Strain Criterion for Typical Pressure Vessel Steel
Authors: Carlos Cuenca, Diego Sarzosa
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Ductile fracture occurs by the mechanism of void nucleation, void growth and coalescence. Potential sites for initiation are second phase particles or non-metallic inclusions. Modelling of ductile damage at the microscopic level is very difficult and complex task for engineers. Therefore, conservative predictions of ductile failure using simple models are necessary during the design and optimization of critical structures like pressure vessels and pipelines. Nowadays, it is well known that the initiation phase is strongly influenced by the stress triaxiality and plastic deformation at the microscopic level. Thus, a simple model used to study the ductile failure under multiaxial stress condition is the Stress Modified Critical Strain (SMCS) approach. Ductile rupture has been study for a structural steel under different stress triaxiality conditions using the SMCS method. Experimental tests are carried out to characterize the relation between stress triaxiality and equivalent plastic strain by notched round bars. After calibration of the plasticity and damage properties, predictions are made for low constraint bending specimens with and without side grooves. Stress/strain fields evolution are compared between the different geometries. Advantages and disadvantages of the SMCS methodology are discussed.Keywords: damage, SMSC, SEB, steel, failure
Procedia PDF Downloads 29719061 Effect of Urban Solid Waste Management Practices on the Sustainability of Urban Infrastructure in Sokoto Metropolis
Authors: Rilwanu, Bello, Usmn Bello Saad, Hamza Umar Yaro, Isyka Ibrahim, Adebayo Oluwole, Jimoh Abdurrahman
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Urban solid waste management is a critical issue affecting the sustainability of urban infrastructure globally. In rapidly growing cities like Sokoto metropolis inefficient waste management practices led to significant environmental and economic challenges. The research aimed at assessing the effect of waste management practices on the sustainability of urban infrastructure in Sokoto. It also includes assessing the current state of solid waste management practices and its impact on the sustainability of sokoto urban infrastructure. The methodology adopted both primary and secondary sources of data. The targeted population include the staff of SUDA, STEPA and some of the resident in the metropolis. Descriptive method was adopted in the analysis and presentation of data. The study revealed that the waste management practice adopted is solid metropolis was very poor as its associated with poor funding, no availability of sufficient vehicles, bad attitude of resident upon waste disposal which led to blockage of streets and water channels which can subsequently lead to flood. The study recommended that the state government need to increase in funding the relevant authority and also provide the waste dumping sites as well as modern vehicles and equipment to ensure effective solid waste management and disposal.Keywords: waste, infrastructure, sustainability, management, S, sustainability, solid waste, urban infrastructure
Procedia PDF Downloads 1819060 Political News Coverage in Philippine Tabloid Sheets: A Critical Discourse Analysis
Authors: Michael Steve Lopez Bernabe
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Political news coverage of tabloid sheets as one of the print media molds or influences public opinions and perceptions. In this study, Critical Discourse Analysis was employed to 30 political news taken from major tabloid sheets in the Philippines in order to determine the linguistics features and other features characterizing the political news in tabloids such as discursive styles, news topics or contexts, journalistic roles and news sources. The political underpinnings through framing were also explored in the study. The results revealed that the linguistics features of the news coverage include moods and modalities (morphology), passivity and transitivity, nominalization, appositives and embedding (syntax), and pre-modifications, the use of verbs and omissions (grammatical features). The discursive features were direct or indirect speech; cohesion; endophora and classifications. In terms of news sources were politicians, experts, and journalists; and the tabloid perform the journalistic roles such as an intervention, watchdog, loyal-facilitator, service, infotainment and civic. The news was also evident of different political underpinnings such as game or strategic framing, conflict framing, human interest framing, attrition of responsibility framing, morality framing, economic consequences framing and issue framing.Keywords: critical discourse analysis, political news, applied linguistics, Philippines, tabloid sheets
Procedia PDF Downloads 4619059 Stability Characteristics of Angle Ply Bi-Stable Laminates by Considering the Effect of Resin Layers
Authors: Masih Moore, Saeed Ziaei-Rad
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In this study, the stability characteristics of a bi-stable composite plate with different asymmetric composition are considered. The interest in bi-stable structures comes from their ability that these structures can have two different stable equilibrium configurations to define a discrete set of stable shapes. The structures can easily change the first stable shape to the second one by a simple snap action. The main purpose of the current research is to consider the effect of including resin layers on the stability characteristics of bi-stable laminates. To this end and In order to determine the magnitude of the loads that are responsible for snap through and snap back phenomena between two stable shapes of the laminate, a non-linear finite element method (FEM) is utilized. An experimental investigation was also carried out to study the critical loads that caused snapping between two different stable shapes. Several specimens were manufactured from T300/5208 graphite-epoxy with [0/90]T, [-30/60]T, [-20/70]T asymmetric stacking sequence. In order to create an accurate finite element model, different thickness of resin layers created during the manufacturing process of the laminate was measured and taken into account. The geometry of each lamina and the resin layers was characterized by optical microscopy from different locations of the laminates thickness. The exact thickness of each lamina and the resin layer in all specimens with [0/90]T,[-30/60]T, [-20/70]T stacking sequence were determined by using image processing technique.Keywords: bi-stable laminates, finite element method, graphite-epoxy plate, snap behavior
Procedia PDF Downloads 24319058 Evaluating the Feasibility of Magnetic Induction to Cross an Air-Water Boundary
Authors: Mark Watson, J.-F. Bousquet, Adam Forget
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A magnetic induction based underwater communication link is evaluated using an analytical model and a custom Finite-Difference Time-Domain (FDTD) simulation tool. The analytical model is based on the Sommerfeld integral, and a full-wave simulation tool evaluates Maxwell’s equations using the FDTD method in cylindrical coordinates. The analytical model and FDTD simulation tool are then compared and used to predict the system performance for various transmitter depths and optimum frequencies of operation. To this end, the system bandwidth, signal to noise ratio, and the magnitude of the induced voltage are used to estimate the expected channel capacity. The models show that in seawater, a relatively low-power and small coils may be capable of obtaining a throughput of 40 to 300 kbps, for the case where a transmitter is at depths of 1 to 3 m and a receiver is at a height of 1 m.Keywords: magnetic induction, FDTD, underwater communication, Sommerfeld
Procedia PDF Downloads 12519057 Developing Critical-Process Skills Integrated Assessment Instrument as Alternative Assessment on Electrolyte Solution Matter in Senior High School
Authors: Sri Rejeki Dwi Astuti, Suyanta
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The demanding of the asessment in learning process was impact by policy changes. Nowadays, the assessment not only emphasizes knowledge, but also skills and attitude. However, in reality there are many obstacles in measuring them. This paper aimed to describe how to develop instrument of integrated assessment as alternative assessment to measure critical thinking skills and science process skills in electrolyte solution and to describe instrument’s characteristic such as logic validity and construct validity. This instrument development used test development model by McIntire. Development process data was acquired based on development test step and was analyzed by qualitative analysis. Initial product was observed by three peer reviewer and six expert judgment (two subject matter expert, two evaluation expert and two chemistry teacher) to acquire logic validity test. Logic validity test was analyzed using Aiken’s formula. The estimation of construct validity was analyzed by exploratory factor analysis. Result showed that integrated assessment instrument has 0,90 of Aiken’s Value and all item in integrated assessment asserted valid according to construct validity.Keywords: construct validity, critical thinking skills, integrated assessment instrument, logic validity, science process skills
Procedia PDF Downloads 26319056 Experience of Transfering Critically Ill Patients on a Transport Ventilator in a Lower Middle-Income Country-Uganda
Authors: Baluku Nathan
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Transferring critically ill patients from one health facility to another poses a major risk to the patient because of increased oxygen demands. transferring patients with critical COVID-19 from a rural health canter in a rural district to a national referral hospital over 350 km in 7 hours would require three size H oxygen cylinders for successful transfer. It was always difficult to arrange the three size cylinders in the ambulance as workspace was greatly compromised for the ambulance assistant. Purpose: The purpose of this study was to investigate the impact and effectiveness of transport ventilators on the transportation of the critically ill patients from rural health canters to national referral hospitals in Uganda. Methodology: This was a descriptive cross-sectional study conducted in sept 2022 among critical care nurses and ambulance assistants who had used both methods of transportation (ventilators and cylinders). A semi structured questionnaire was used to collect quantitative data after informed consent. Results: From the findings, distribution of transport ventilators to the regional referral hospitals by the Ministry of Health has gradually improved patient transfer as the team requires less than one size oxygen cylinder to successfully transfer a patient. We use two ambulance assistants (a critical care nurse and another nurse who has been trained on use of the ventilator) when transferring patients with critical COVID-19 as the teams have to interchange over the long distance. Conclusions: Transport ventilators are effective and efficient in transferring critically ill patients, therefore should be rolled out to lower levels coupled with user training to improve outcomes of patients transferred in ambulances in lower income countries.Keywords: emergency medical technician, critically ill, COVID-19, transport ventilator
Procedia PDF Downloads 8619055 Multiple Fault Diagnosis in Digital Circuits using Critical Path Tracing and Enhanced Deduction Algorithm
Authors: Mohamed Mahmoud
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This paper has developed an effect-cause analysis technique for fault diagnosis in digital circuits. The main algorithm of our technique is based on the Enhanced Deduction Algorithm, which processes the real response of the CUT to the applied test T to deduce the values of the internal lines. An experimental version of the algorithm has been implemented in C++. The code takes about 7592 lines. The internal values are determined based on the logic values under the permanent stuck-fault model. Using a backtracking strategy guarantees that the actual values are covered by at least one solution, or no solution is found.Keywords: enhanced deduction algorithm, backtracking strategy, automatic test equipment, verfication
Procedia PDF Downloads 12019054 The Effect of Absolute and Relative Deprivation on Homicides in Brazil
Authors: Temidayo James Aransiola, Vania Ceccato, Marcelo Justus
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This paper investigates the effect of absolute deprivation (proxy unemployment) and relative deprivation (proxy income inequality) on homicide levels in Brazil. A database from the Brazilian Information System about Mortality and Census of the year 2000 and 2010 was used to estimate negative binomial models of homicide levels controlling for socioeconomic, demographic and geographic factors. Findings show that unemployment and income inequality affect homicides levels and that the effect of the former is more pronounced compared to the latter. Moreover, the combination of income inequality and unemployment exacerbates the overall effect of deprivation on homicide levels.Keywords: deprivation, inequality, interaction, unemployment, violence
Procedia PDF Downloads 14619053 A Microsurgery-Specific End-Effector Equipped with a Bipolar Surgical Tool and Haptic Feedback
Authors: Hamidreza Hoshyarmanesh, Sanju Lama, Garnette R. Sutherland
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In tele-operative robotic surgery, an ideal haptic device should be equipped with an intuitive and smooth end-effector to cover the surgeon’s hand/wrist degrees of freedom (DOF) and translate the hand joint motions to the end-effector of the remote manipulator with low effort and high level of comfort. This research introduces the design and development of a microsurgery-specific end-effector, a gimbal mechanism possessing 4 passive and 1 active DOFs, equipped with a bipolar forceps and haptic feedback. The robust gimbal structure is comprised of three light-weight links/joint, pitch, yaw, and roll, each consisting of low-friction support and a 2-channel accurate optical position sensor. The third link, which provides the tool roll, was specifically designed to grip the tool prongs and accommodate a low mass geared actuator together with a miniaturized capstan-rope mechanism. The actuator is able to generate delicate torques, using a threaded cylindrical capstan, to emulate the sense of pinch/coagulation during conventional microsurgery. While the tool left prong is fixed to the rolling link, the right prong bears a miniaturized drum sector with a large diameter to expand the force scale and resolution. The drum transmits the actuator output torque to the right prong and generates haptic force feedback at the tool level. The tool is also equipped with a hall-effect sensor and magnet bar installed vis-à-vis on the inner side of the two prongs to measure the tooltip distance and provide an analogue signal to the control system. We believe that such a haptic end-effector could significantly increase the accuracy of telerobotic surgery and help avoid high forces that are known to cause bleeding/injury.Keywords: end-effector, force generation, haptic interface, robotic surgery, surgical tool, tele-operation
Procedia PDF Downloads 11919052 Theorizing Digital Transformation, Digitization and Digitalization in Africa Emerging Research in Digital Business: A Critical Review of the Current Scholarship
Authors: Ayanda Magida
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The paper aims to provide a critical review of the current state-of-the-art literature on emerging digital business theories. They are specifically focusing on the emergent theories on digital transformation, digitization, and digitalization and their importance in the global south. Digital business is an emergent field that cuts across the different existing disciplines. The paper is threefold- to provide the conceptual and theoretical definition of the DT, digitization and digitization. There is a growing need to provide some of the differences between digitalization, digitization and digital transformation from a theoretical and conceptual basis. These tend to be confused and often use interchangeably the second aim is to focus on the emerging theories on digital transformation and digital business. Finally, the paper provides some critical review of the importance of scholarship in the field from the global south. The systematic review of the literature was conducted through the different research databases to provide some of the major theories in the field of digital business and critically argue for the global south stance. Much of the research on the development and adoption of digital technologies, specifically digital transformation, has been done in the west and developed countries. There is thus a dearth of research conducted in developing countries and the global south.Keywords: digital transformation, digitization, digital business, digitalization
Procedia PDF Downloads 27519051 The Effect of Relationship Marketing on Service Quality and Customer Satisfaction without Service Providers' Emotional Intelligence: The Case of the Insurance Industry in Ghana
Authors: Frank Frimpong Opuni, Michael Mba Allan, Kwame Adu-Gyamfi, Michael Sarkodie Baffoe
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This paper assesses the effect of relationship marketing on service quality and customer satisfaction from the perspective of the moderating role of emotional intelligence in the insurance industry in Ghana. A descriptive quantitative research technique was employed. A random sample of 384 each of customers and service providers in 3 insurance firms in Accra were used as the source of data. According to findings, emotional intelligence makes a strong positive effect on relationship marketing at 5% significance level, r (283) = .817, p = .000. Though relationship marketing makes a strong positive effect on service quality (r = .767, p < .05) and customer satisfaction (r = .647, p < .05), this effect becomes insignificant (p > .05) when the effect of emotional intelligence on relationship marketing is controlled for. It is therefore recommended that insurance firms give priority to equipping their relationship employees with emotional intelligence to maximise service quality and customer satisfaction.Keywords: relationship marketing, service quality, customer satisfaction, emotional intelligence
Procedia PDF Downloads 48119050 Navigating the Ripple Effect: Deconstructing the Multilayered Impact of Fuel Subsidy Removal on Nigeria’s Educational Landscape
Authors: Abimbola Mobolanle Adu, Marcus Tayo Akinlade
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This comprehensive study systematically dissects the intricate interplay between the removal of fuel subsidy and its multifaceted repercussions on Nigeria's educational system. Originating in the 1970s, the fuel subsidy policy initially conceived to curtail fuel costs and faced financial unsustainability. In 2023, President Bola Tinubu's administration announced its cessation. The resultant escalation in petroleum product prices precipitated challenges within the education sector, manifesting as heightened administrative costs, increased student fees, amplified dropout rates, and others. Employing a qualitative research methodology, grounded in Critical Theory, the study draws from diverse secondary sources and employs content analysis to unravel the intricate layers of this issue. Critical Theory provides a lens through which the power dynamics, socio-economic structures, and ideological influences shaping policy decisions can be critically examined, offering a deeper understanding of the multifaceted impact. Findings underscore the imperative for strategic interventions, advocating for investments in technology and the exploration of alternative energy sources. The paper concludes by emphasizing the pivotal role of education, advocating for nuanced policies to alleviate the impact on both private and public educational institutions. In essence, this research contributes nuanced insights into the labyrinthine dynamics between fuel subsidy policies and the educational sector, underscoring the exigency for meticulous interventions to fortify the nation's educational foundation.Keywords: administration, education, fuel subsidy, policy, multilayered impact
Procedia PDF Downloads 5919049 The Effects of Critical Incident Stress Debriefing and Other Related Interventions on the Psychological Recovery of Earthquake Survivors
Authors: Joyce Fernandez
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This study examined the effects of critical incident stress debriefing and other related interventions on the psychological recovery of earthquake survivors. It is a mixed experimental and qualitative study using post-test only control group design and focus group discussion. After the conduct of critical incident stress debriefing activities and other related interventions in the form of counseling and psychiatric treatment to the survivors of a 6.9 magnitude earthquake, a post-test measuring the level of psychological recovery was given to randomized participants categorized as intervention and control groups. Using the traumatic assessment and belief scale as instrument for the quantitative aspect in order to gauge recovery in the psychological need areas of safety, trust, esteem, intimacy and control, the findings are the following: Intervention group participants have relatively better adjustment along the five psychological need areas compared to the control group participants; there is no significant difference in the psychological recovery among female and male participants of the invention and control groups and; there are significant differences between intervention and control groups in the psychological need areas of self-safety, self-trust, other-trust, self-esteem, and self-intimacy. Using a guided interview for the qualitative data, the themes derived are the following. Safety: The world is an unsafe place to live because of the calamities. Trust: Trust and dependence are anchored on the family. Esteem: Participants are having confused self-worth. Intimacy: Participants are thriving on attachment with their family. Control: Participants have unaltered desire to help but feeling restricted because of personal and logistical concerns.As an outcome of the study a Psychosocial Care Program for Individuals, Families and Communities Affected by Disaster and Trauma was proposed.Keywords: critical incident stress debriefing, earthquake survivors, psychological recovery, related interventions
Procedia PDF Downloads 29319048 A Qualitative Study on Metacognitive Patterns among High and Low Performance Problem Based on Learning Groups
Authors: Zuhairah Abdul Hadi, Mohd Nazir bin Md. Zabit, Zuriadah Ismail
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Metacognitive has been empirically evidenced to be one important element influencing learning outcomes. Expert learners engage in metacognition by monitoring and controlling their thinking, and listing, considering and selecting the best strategies to achieve desired goals. Studies also found that good critical thinkers engage in more metacognition and people tend to activate more metacognition when solving complex problems. This study extends past studies by performing a qualitative analysis to understand metacognitive patterns among two high and two low performing groups by carefully examining video and audio records taken during Problem-based learning activities. High performing groups are groups with majority members scored well in Watson Glaser II Critical Thinking Appraisal (WGCTA II) and academic achievement tests. Low performing groups are groups with majority members fail to perform in the two tests. Audio records are transcribed and analyzed using schemas adopted from past studies. Metacognitive statements are analyzed using three stages model and patterns of metacognitive are described by contexts, components, and levels for each high and low performing groups.Keywords: academic achievement, critical thinking, metacognitive, problem-based learning
Procedia PDF Downloads 28519047 Epigenetic Drugs for Major Depressive Disorder: A Critical Appraisal of Available Studies
Authors: Aniket Kumar, Jacob Peedicayil
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Major depressive disorder (MDD) is a common and important psychiatric disorder. Several clinical features of MDD suggest an epigenetic basis for its pathogenesis. Since epigenetics (heritable changes in gene expression not involving changes in DNA sequence) may underlie the pathogenesis of MDD, epigenetic drugs such as DNA methyltransferase inhibitors (DNMTi) and histone deactylase inhibitors (HDACi) may be useful for treating MDD. The available literature indexed in Pubmed on preclinical drug trials of epigenetic drugs for the treatment of MDD was investigated. The search terms we used were ‘depression’ or ‘depressive’ and ‘HDACi’ or ‘DNMTi’. Among epigenetic drugs, it was found that there were 3 preclinical trials using HDACi and 3 using DNMTi for the treatment of MDD. All the trials were conducted on rodents (mice or rats). The animal models of depression that were used were: learned helplessness-induced animal model, forced swim test, open field test, and the tail suspension test. One study used a genetic rat model of depression (the Flinders Sensitive Line). The HDACi that were tested were: sodium butyrate, compound 60 (Cpd-60), and valproic acid. The DNMTi that were tested were: 5-azacytidine and decitabine. Among the three preclinical trials using HDACi, all showed an antidepressant effect in animal models of depression. Among the 3 preclinical trials using DNMTi also, all showed an antidepressant effect in animal models of depression. Thus, epigenetic drugs, namely, HDACi and DNMTi, may prove to be useful in the treatment of MDD and merit further investigation for the treatment of this disorder.Keywords: DNA methylation, drug discovery, epigenetics, major depressive disorder
Procedia PDF Downloads 18819046 A Statistical Model for the Dynamics of Single Cathode Spot in Vacuum Cylindrical Cathode
Authors: Po-Wen Chen, Jin-Yu Wu, Md. Manirul Ali, Yang Peng, Chen-Te Chang, Der-Jun Jan
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Dynamics of cathode spot has become a major part of vacuum arc discharge with its high academic interest and wide application potential. In this article, using a three-dimensional statistical model, we simulate the distribution of the ignition probability of a new cathode spot occurring in different magnetic pressure on old cathode spot surface and at different arcing time. This model for the ignition probability of a new cathode spot was proposed in two typical situations, one by the pure isotropic random walk in the absence of an external magnetic field, other by the retrograde motion in external magnetic field, in parallel with the cathode surface. We mainly focus on developed relationship between the ignition probability density distribution of a new cathode spot and the external magnetic field.Keywords: cathode spot, vacuum arc discharge, transverse magnetic field, random walk
Procedia PDF Downloads 43419045 Investigation of Changes of Physical Properties of the Poplar Wood in Radial and Longitudinal Axis at Chaaloos Zone
Authors: Afshin Veisi
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In this study, the physical properties of wood in poplar wood (Populous sp.) were analyzed in longitudinal and radial directions of the stem. Three Populous Alba tree were cut in chaloos zone and from each tree, 3 discs were selected at 130cm, half of tree and under of crown. The test samples from pith to bark (heartwood to sapwood) were prepared from these discs for measuring the involved properties such as, wet, dry and critical specific gravity, porosity, volume shrinkage and swelling based on the ASTM standard, and data in two radial and longitudinal directions in the trank were statistically analyzed. Such as, variations of wet, dry and critical specific gravity had in radial direction respectively: irregular increase, increase and increase, and in longitudinal direction respectively: irregular decrease, irregular increase and increase. Results of variations to moisture content and porosity show that in radial direction respectively: irregular increasing and decreasing, and in longitudinal direction from down to up respectively: irregular decreasing and stability. Volume shrinkage and swelling variations show in radial direction irregular and in longitudinal axial regular decreasing.Keywords: poplar wood, physical properties, shrinkage, swelling, critical specific gravity, wet specific gravity, dry specific gravity
Procedia PDF Downloads 27819044 Moral Hazard under the Effect of Bailout and Bailin Events: A Markov Switching Model
Authors: Amira Kaddour
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To curb the problem of liquidity in times of financial crises, two cases arise; the Bailout or Bailin, two opposite choices that elicit the analysis of their effect on moral hazard. This paper attempts to empirically analyze the effect of these two types of events on the behavior of investors. For this end, we use the Emerging Market Bonds Index (EMBI-JP Morgan), and its excess of return, to detect the change in the risk premia through a Markov switching model. The results showed the transition to two types of regime and an effect on moral hazard; Bailout is an incentive of moral hazard, Bailin effectiveness remains subject of credibility.Keywords: Bailout, Bailin, Moral hazard, financial crisis, Markov switching
Procedia PDF Downloads 46619043 The Effects of the Aspect Ratio of a Flexible Cylinder on the Vortex Dynamics
Authors: Abouzar Kaboudian, Ravi Chaithanya Mysa, Boo Cheong Khoo, Rajeev Kumar Jaiman
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The vortex structures observed in the wake of a flexible cylinder can be significantly different from those of a traditional vibrating, spring mounted, rigid cylinder. These differences can significantly affect the VIV characteristics of the flow and subsequently the VIV response of the cylindrical structures. In this work, we present how the aspect ratio of a flexible cylinder can change the vortex structures in its wake. We will discuss different vortex dynamics which can be observed in the wake of the vibrating flexible cylinder, and how they can affect the vibrational response of the cylinder. Moreover, we will study the transition of these structures versus the aspect ratio of the flexible cylinder. We will discuss how these transitions affect the in-line and transverse forces on the structure. In the end, we will provide general guidelines on the minimum acceptable aspect ratio for the offshore riser studies which may have grave implications for future numerical and experimental works.Keywords: aspect ratio, flexible cylinder, vortex-shedding, VIV
Procedia PDF Downloads 488