Search results for: semarang state university
8332 External Business Environment and Sustainability of Micro, Small and Medium Enterprises in Jigawa State, Nigeria
Authors: Shehu Isyaku
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The general objective of the study was to investigate ‘the relationship between the external business environment and the sustainability of micro, small and medium enterprises (MSMEs) in Jigawa state’, Nigeria. Specifically, the study was to examine the relationship between 1) the economic environment, 2) the social environment, 3) the technological environment, and 4) the political environment and the sustainability of MSMEs in Jigawa state, Nigeria. The study was drawn on Resource-Based View (RBV) Theory and Knowledge-Based View (KBV). The study employed a descriptive cross-sectional survey design. A researcher-made questionnaire was used to collect data from the 350 managers/owners who were selected using stratified, purposive and simple random sampling techniques. Data analysis was done using means and standard deviations, factor analysis, Correlation Coefficient, and Pearson Linear Regression analysis. The findings of the study revealed that the sustainability potentials of the managers/owners were rated as high potential (economic, environmental, and social sustainability using 5 5-point Likert scale. Mean ratings of effectiveness of the external business environment were; as highly effective. The results from the Pearson Linear Regression Analysis rejected the hypothesized non-significant effect of the external business environment on the sustainability of MSMEs. Specifically, there is a positive significant relationship between 1) economic environment and sustainability; 2) social environment and sustainability; 3) technological environment and sustainability and political environment and sustainability. The researcher concluded that MSME managers/owners have a high potential for economic, social and environmental sustainability and that all the constructs of the external business environment (economic environment, social environment, technological environment and political environment) have a positive significant relationship with the sustainability of MSMEs. Finally, the researcher recommended that 1) MSME managers/owners need to develop marketing strategies and intelligence systems to accumulate information about the competitors and customers' demands, 2) managers/owners should utilize the customers’ cultural and religious beliefs as an opportunity that should be utilized while formulating business strategies.Keywords: business environment, sustainability, small and medium enterprises, external business environment
Procedia PDF Downloads 568331 Water Stress Response Profiling of Nigerian Bambara Groundnut (Vigna subterranea L. Verdc.) Germplasm and Genetic Diversity Studies of Some Selected Accessions Using SSR Markers
Authors: Dorcas Ropo Abejide, Olamide Ahmed Falusi, Oladipupo Abdulazeez Yusuf Daudu, Bolaji Zuluqurineen Salihu, Muhammad Liman Muhammad
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This study evaluated the morpho-agronomic response of twenty-four (24) Nigerian Bambara groundnut landraces to water stress and genetic diversity of some selected accessions using SSR markers. The studies were carried out in the botanical garden of the Department of Plant Biology, Federal University of Technology, Minna, Niger State, Nigeria in a randomized complete block design using three replicates. Molecular analysis using SSR primers was carried out at the International Institute of Tropical Agriculture (IITA) Ibadan in order to characterize ten selected accessions comprising the seven most drought tolerant and three most susceptible accessions from the 24 accessions evaluated. Results revealed that water stress decreased morpho-agronomic traits such as plant height, leaf area, number of leaves per plant, seed yield, etc. A total of 22 alleles were detected by the SSR markers used with a mean number of 4 allelles. SSR markers MBamCO₃₃, Primer 65, and G358B2-D15 each detected 4 allelles, while Primer 3FR and 4FR detected 5 allelles each. The study revealed significantly high polymorphisms in 10 Loci. The mean value of polymorpic information content was 0.6997, implying the usefulness of the primers used in identifying genetic similarities and differences among the Bambara groundnut genotypes. The SSR analysis revealed a comparable pattern between genetic diversity and drought tolerance of the genotypes. The UPGMA dendrogram showed that at a genetic distance of 0.1, the accessions were grouped into three groups according to their level of tolerance to drought. The two most drought-tolerant accessions were grouped together, and the 5th and 6th most drought-tolerant accessions were also grouped together. This suggests that the genotypes grouped together may be genetically close, may possess similar genes, or have a common origin. The degree of genetic variants obtained from this profiling could be useful in Bambara groundnut breeding for drought tolerance. The identified drought tolerant Bambara groundnut landraces are important genetic resources for drought stress tolerance breeding programme of Bambara groundnut. The genotypes are also useful for germplasm conservation and global implications.Keywords: Bambara groundnut, genetic diversity, germplasm, SSR markers, water stress
Procedia PDF Downloads 618330 Influence of the Molecular Architecture of a Polycarboxylate-Based Superplasticizer on the Rheological and Physicomechanical Properties of Cement Pastes
Authors: Alya Harichane, Abderraouf Achour, Abdelbaki Benmounah
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The main difficulty encountered in the formulation of high-performance concrete (HPC) consists in choosing the most efficient cement-superplasticizer pair allowing to obtain maximum water reduction, good workability of the concrete in the fresh state, and very good mechanical resistance in the hardened state. The aim of this work is to test the efficiency of three polycarboxylate ether-based superplasticizers (PCE) marketed in Algeria with CEMI 52.5 R cement and to study the effect of chemical structure of PCE on zeta potential, rheological and mechanical properties of cement pastes. The property of the polymers in cement was tested by a Malvern Zetasizer 2000 apparatus and VT 550 viscometer. Results showed that the zeta potential and its rheological properties are related to the molecular weight and the density carboxylic of PCE. The PCE with a moderate molecular weight and the highest carboxylic groups had the best dispersion (high value of zeta potential) and lowest viscosity. The effect of the chemical structure of PCEs on mechanical properties is evaluated by the formulation of cement mortar with these PCEs. The result shows that there is a correlation between the zeta potential of polymer and the compressive strength of cement paste.Keywords: molecular weight, polycarboxylate-ether superplasticizer, rheology, zeta potential
Procedia PDF Downloads 908329 The Sociology of the Facebook: An Exploratory Study
Authors: Liana Melissa E. de la Rosa, Jayson P. Ada
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This exploratory study was conducted to determine the sociology of the Facebook. Specifically, it aimed to know the socio-demographic profile of the respondents in terms of age, sex, year level and monthly allowance; find out the common usage of Facebook to the respondents; identify the features of Facebook that are commonly used by the respondents; understand the benefits and risks of using the Facebook; determine how frequent the respondents use the Facebook; and find out if there is a significant relationship between socio-demographic profile of the respondents and their Facebook usage. This study used the exploratory research design and correlational design employing research survey questionnaire as its main data gathering instrument. Students of the University of Eastern Philippines were selected as the respondents of this study through quota sampling. Ten (10) students were randomly selected from each college of the university. Based on the findings of this study, the following conclusion were drawn: The majority of the respondents are aged 18 and 21 old, female, are third year students, and have monthly allowance of P 2,000 above. On the respondents’ usage of Facebook, the majority of use the Facebook on a daily basis for one to two (1-2) hours everyday. And most users used Facebook by renting a computer in an internet cafe. On the use of Facebook, most users have created their profiles mainly to connect with people and gain new friends. The most commonly used features of Facebook, are: photos application, like button, wall, notification, friend, chat, network, groups and “like” pages status updates, messages and inbox and events. While the other Facebook features that are seldom used by the respondents are games, news feed, user name, video sharing and notes. And the least used Facebook features are questions, poke feature, credits and the market place. The respondents stated that the major benefit that the Facebook has given to its users is its ability to keep in touch with family members or friends while the main risk identified is that the users can become addicted to the Internet. On the tests of relationships between the respondents’ use of Facebook and the four (4) socio-demographic profile variables: age, sex, year level, and month allowance, were found to be not significantly related to the respondents’ use of the Facebook. While the variable found to be significantly related was gender.Keywords: Facebook, sociology, social networking, exploratory study
Procedia PDF Downloads 2918328 Prediction Model of Body Mass Index of Young Adult Students of Public Health Faculty of University of Indonesia
Authors: Yuwaratu Syafira, Wahyu K. Y. Putra, Kusharisupeni Djokosujono
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Background/Objective: Body Mass Index (BMI) serves various purposes, including measuring the prevalence of obesity in a population, and also in formulating a patient’s diet at a hospital, and can be calculated with the equation = body weight (kg)/body height (m)². However, the BMI of an individual with difficulties in carrying their weight or standing up straight can not necessarily be measured. The aim of this study was to form a prediction model for the BMI of young adult students of Public Health Faculty of University of Indonesia. Subject/Method: This study used a cross sectional design, with a total sample of 132 respondents, consisted of 58 males and 74 females aged 21- 30. The dependent variable of this study was BMI, and the independent variables consisted of sex and anthropometric measurements, which included ulna length, arm length, tibia length, knee height, mid-upper arm circumference, and calf circumference. Anthropometric information was measured and recorded in a single sitting. Simple and multiple linear regression analysis were used to create the prediction equation for BMI. Results: The male respondents had an average BMI of 24.63 kg/m² and the female respondents had an average of 22.52 kg/m². A total of 17 variables were analysed for its correlation with BMI. Bivariate analysis showed the variable with the strongest correlation with BMI was Mid-Upper Arm Circumference/√Ulna Length (MUAC/√UL) (r = 0.926 for males and r = 0.886 for females). Furthermore, MUAC alone also has a very strong correlation with BMI (r = 0,913 for males and r = 0,877 for females). Prediction models formed from either MUAC/√UL or MUAC alone both produce highly accurate predictions of BMI. However, measuring MUAC/√UL is considered inconvenient, which may cause difficulties when applied on the field. Conclusion: The prediction model considered most ideal to estimate BMI is: Male BMI (kg/m²) = 1.109(MUAC (cm)) – 9.202 and Female BMI (kg/m²) = 0.236 + 0.825(MUAC (cm)), based on its high accuracy levels and the convenience of measuring MUAC on the field.Keywords: body mass index, mid-upper arm circumference, prediction model, ulna length
Procedia PDF Downloads 2158327 First Principle Studies on the Structural, Electronic and Magnetic Properties of Some BaMn-Based Double Perovskites
Authors: Amel Souidi, S. Bentata, B. Bouadjemi, T. Lantri, Z. Aziz
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Perovskite materials which include magnetic elements have relevance due to the technological perspectives in the spintronics industry. In this work, we have investigated the structural, electronic and magnetic properties of double perovskites Ba2MnXO6 with X= Mo and W by using the full-potential linearized augmented plane wave (FP-LAPW) method based on Density Functional Theory (DFT) [1, 2] as implemented in the WIEN2K [3] code. The interchange-correlation potential was included through the generalized gradient approximation (GGA) [4] as well as taking into account the on-site coulomb repulsive interaction in (GGA+U) approach. We have analyzed the structural parameters, charge and spin densities, total and partial densities of states. The results show that the materials crystallize in the 225 space group (Fm-3m) and have a lattice parameter of about 7.97 Å and 7.95 Å for Ba2MnMoO6 and Ba2MnWO6, respectively. The band structures reveal a metallic ferromagnetic (FM) ground state in Ba2MnMoO6 and half-metallic (HM) ferromagnetic (FM) ground state in the Ba2MnWO6 compound, with total magnetic moment equal 2.9951μB (Ba2MnMoO6 ) and 4.0001μB (Ba2MnWO6 ). The GGA+U calculations predict an energy gap in the spin-up bands in Ba2MnWO6. So we estimate that this material with HM-FM nature implies a promising application in spin-electronics technology.Keywords: double perovskites, electronic structure, first-principles, semiconductors
Procedia PDF Downloads 3698326 Reclaiming Corporate Social Responsibility: A Research Agenda for Socio-Industrial Interdependence
Authors: Leah Ritchie
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By many accounts, the most recent economic recession and subsequent lack-luster recovery has demonstrated that corporate social responsibility is in a state of crisis. This crisis represents an opportunity for CSR scholars to play a role in restoring long-term economic growth and consumer confidence. In its current state however, CSR may not be in a position to facilitate positive change. In an attempt to remain relevant, the field has shifted toward a performance-based agenda that demonstrates in practical terms, how CSR can positively affect the financial and strategic performance of the firm. This paper argues that if CSR is to play a central role in helping to create a more equitable balance of power between industry and society, it must demonstrate the symbiotic nature of the relationship between these two entities, not just in terms of compartmentalized strategic and financial gain for the firm, but also toward maintaining a 'do no harm' imperative. Given the evidence that harm done to society is ultimately turned back on the firm, this is not simply a moralistic imperative. In order to affect change, CSR must also create an activist agenda to raise consciousness among the general citizenry toward mobilizing, uncovering, and repairing breeches in the implicit social contract between business and society.Keywords: corporate social responsibility, multiple stakeholder view, economic recession, housing crisis
Procedia PDF Downloads 2158325 On the Path of Radicalization: Policing of Muslim Americans Post 9/11
Authors: Hagar Elsayed
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This case study examines the framing of the diverse populations of Arab, Muslim and South Asian immigrants and their descendants in local communities by both federal and local law enforcement agencies. It explores how urban spaces and policing are constructed as necessary components of national security in the context of the war on terror by focusing on practices employed in local spaces such as Dearborn, Michigan and training methods adopted on a national level. The proliferation of American Arabs as ‘terrorist’ works to legitimize not only increasing state surveillance, but also military strategies which infringe on ‘inside’ spaces. Sustaining these progressively militarized civil policing operations, which demand intense mobilization of state power, requires that whole neighborhoods and districts are reimagined to portray these geographies in a certain light. This case study is central in understanding how Arab, South Asian, and Muslim civilians’ transformation into a “national security” issue have created militarized police enforcement agencies that employ military tactics to map the terrain of Otherness. This study looks at how race factors into key recent incidents, and asks whether this militarization builds from past forms of racist policing, and whether these specific incidents are reflective of larger patterns or whether they are just isolated incidents.Keywords: American-Muslims, Arabs, militarization, policing
Procedia PDF Downloads 1378324 Assessment of Level of Sedation and Associated Factors Among Intubated Critically Ill Children in Pediatric Intensive Care Unit of Jimma University Medical Center: A Fourteen Months Prospective Observation Study, 2023
Authors: Habtamu Wolde Engudai
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Background: Sedation can be provided to facilitate a procedure or to stabilize patients admitted in pediatric intensive care unit (PICU). Sedation is often necessary to maintain optimal care for critically ill children requiring mechanical ventilation. However, if sedation is too deep or too light, it has its own adverse effects, and hence, it is important to monitor the level of sedation and maintain an optimal level. Objectives: The objective is to assess the level of sedation and associated factors among intubated critically ill children admitted to PICU of JUMC, Jimma. Methods: A prospective observation study was conducted in the PICU of JUMC in September 2021 in 105 patients who were going to be admitted to the PICU aged less than 14 and with GCS >8. Data was collected by residents and nurses working in PICU. Data entry was done by Epi data manager (version 4.6.0.2). Statistical analysis and the creation of charts is going to be performed using SPSS version 26. Data was presented as mean, percentage and standard deviation. The assumption of logistic regression and the result of the assumption will be checked. To find potential predictors, bi-variable logistic regression was used for each predictor and outcome variable. A p value of <0.05 was considered as statistically significant. Finally, findings have been presented using figures, AOR, percentages, and a summary table. Result: in this study, 105 critically ill children had been involved who were started on continuous or intermittent forms of sedative drugs. Sedation level was assessed using a comfort scale three times per day. Based on this observation, we got a 44.8% level of suboptimal sedation at the baseline, a 36.2% level of suboptimal sedation at eight hours, and a 24.8% level of suboptimal sedation at sixteen hours. There is a significant association between suboptimal sedation and duration of stay with mechanical ventilation and the rate of unplanned extubation, which was shown by P < 0.05 using the Hosmer-Lemeshow test of goodness of fit (p> 0.44).Keywords: level of sedation, critically ill children, Pediatric intensive care unit, Jimma university
Procedia PDF Downloads 618323 Intelligent Decision Support for Wind Park Operation: Machine-Learning Based Detection and Diagnosis of Anomalous Operating States
Authors: Angela Meyer
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The operation and maintenance cost for wind parks make up a major fraction of the park’s overall lifetime cost. To minimize the cost and risk involved, an optimal operation and maintenance strategy requires continuous monitoring and analysis. In order to facilitate this, we present a decision support system that automatically scans the stream of telemetry sensor data generated from the turbines. By learning decision boundaries and normal reference operating states using machine learning algorithms, the decision support system can detect anomalous operating behavior in individual wind turbines and diagnose the involved turbine sub-systems. Operating personal can be alerted if a normal operating state boundary is exceeded. The presented decision support system and method are applicable for any turbine type and manufacturer providing telemetry data of the turbine operating state. We demonstrate the successful detection and diagnosis of anomalous operating states in a case study at a German onshore wind park comprised of Vestas V112 turbines.Keywords: anomaly detection, decision support, machine learning, monitoring, performance optimization, wind turbines
Procedia PDF Downloads 1688322 Enhancing Learning for Research Higher Degree Students
Authors: Jenny Hall, Alison Jaquet
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Universities’ push toward the production of high quality research is not limited to academic staff and experienced researchers. In this environment of research rich agendas, Higher Degree Research (HDR) students are increasingly expected to engage in the publishing of good quality papers in high impact journals. IFN001: Advanced Information Research Skills (AIRS) is a credit bearing mandatory coursework requirement for Queensland University of Technology (QUT) doctorates. Since its inception in 1989, this unique blended learning program has provided the foundations for new researchers to produce original and innovative research. AIRS was redeveloped in 2012, and has now been evaluated with reference to the university’s strategic research priorities. Our research is the first comprehensive evaluation of the program from the learner perspective. We measured whether the program develops essential transferrable skills and graduate capabilities to ensure best practice in the areas of publishing and data management. In particular, we explored whether AIRS prepares students to be agile researchers with the skills to adapt to different research contexts both within and outside academia. The target group for our study consisted of HDR students and supervisors at QUT. Both quantitative and qualitative research methods were used for data collection. Gathering data was by survey and focus groups with qualitative responses analyzed using NVivo. The results of the survey show that 82% of students surveyed believe that AIRS assisted their research process and helped them learn skills they need as a researcher. The 18% of respondents who expressed reservation about the benefits of AIRS were also examined to determine the key areas of concern. These included trends related to the timing of the program early in the candidature and a belief among some students that their previous research experience was sufficient for postgraduate study. New insights have been gained into how to better support HDR learners in partnership with supervisors and how to enhance learning experiences of specific cohorts, including international students and mature learners.Keywords: data management, enhancing learning experience, publishing, research higher degree students, doctoral students
Procedia PDF Downloads 2768321 The Role of Medical Professionals in Imparting Drug Abuse Education to Secondary School Children
Authors: Hana Ashique, Florence Onabanjo
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Objectives: Research on drug abuse education in secondary schools has highlighted the discrepancy between drug policies and practice. Drug abuse is closely associated with child mental health, and with increasing drug overdose deaths in the UK, approximately doubling in the last 30 years, it becomes important to revolutionise drug abuse education. Medical professionals from the University of Nottingham piloted a drug abuse workshop at a state school in Nottingham for children between the age of 14-15 years. An interactive and educational approach was implemented, which explained addiction from a medical perspective. The workshop aimed to debunk medical beliefs children harboured about drugs and to support children in making informed drug choices. Methods: The sample group consisted of six cohorts of 30 children from year 10. The workshop was delivered in three segments to each cohort. In the first segment, the children were introduced to the physiological mechanisms behind drug dependence and reward pathways. The second segment consisted of interactive discussions between the children and medical professionals. This also involved conversations between the children about their perspectives on drug abuse, thereby co-creating knowledge. The third segment used art to incorporate storytelling from the perspective of a year ten child. This exercise investigated the causes that led children to abuse drugs. A feedback questionnaire was distributed among the children to analyse the impact of the workshop. Results: The children answered eight questions. 56% agreed/strongly agreed that they found being taught by medical professionals effective. 50% disagreed, strongly disagreed, or felt neutral that they had received sufficient education about drug abuse previously. Notably, 20% agreed that they feel more likely to ask for help from a medical professional or organisation if they need it. Conclusion: The results highlighted the relevance of medical professionals to function as peer educators in drug abuse education to secondary school children. This would build trust between children and the medical profession within the community. However, a minority proportion of children showed keenness to seek support from medical professionals or organisations for their mental health if they needed it. This exposed the anxiety children have in coming forward to seek professional help. In order to work towards a child-centred approach, educational policies and practices need to align. Similar workshops and research may need to be conducted to expose different perspectives toward drug abuse education.Keywords: adolescent mental health, evidence-based teaching, drug abuse awareness, medical professional led workshops
Procedia PDF Downloads 248320 Influence of Procurement Methods on Cost Performance of Building Projects in Gombe State, Nigeria
Authors: S. U. Kunya, S. Abdulkadir, M. A. Anas, L. Z. Adam
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Procurement methods is described as systems of contractual arrangements used by the contractor in order to secure the design and construction services based on the stipulated cost and within the required time and quality. Despite that, major projects in the Nigerian construction industry failed because of wrong procurement methods with major consequences leads to cost overrun which needs to find lasting solution. The aim of the study is to evaluate the influence of procurement methods on cost performance of building projects in Gombe State, Nigeria. Study adopts descriptive and explorative design approach. Data were collected through administering of one hundred questionnaire using convenient sampling techniques. Data analyses using percentages, mean value and Anova analysis. Major finding show that more than fifty percent (50%) of procurement methods available are mainly utilized in the study area and the top procurement methods that have high impacts on cost performance as compare with the other methods is project management and direct labour procurement methods. The results of hypothesis’ tests with pvalue 0.12 and 0.07 validated that there was no significant variation in the perception of stakeholders’ on the impacts of procurements methods on cost performance. Therefore, the study concluded that projects management and direct labour are the most appropriate procurement methods that will ensure successful completion of project at stipulated cost in building projects.Keywords: cost, effects, performance, procurement, projects
Procedia PDF Downloads 2248319 Hematological Malignancies in Children and Parental Occupational Exposure
Authors: H. Kalboussi, A. Aloui, W. Boughattas, M. Maoua, A. Brahem, S. Chatti, O. El Maalel, F. Debbabi, N. Mrizak, Y. Ben Youssef, A. Khlif, I. Bougmiza
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Background: In recent decades, the incidence of children's hematological malignancies has been increasing worldwide including Tunisia. Their severity is reflected in the importance of the medical, social and economic impact. This increase remains fully unexplained, and the involvement of genetic, environmental and occupational factors is strongly suspected. Materials and Methods: Our study is a cross-sectional survey of the type case-control conducted in the University Hospital of Farhat Hached of Sousse during the period ranging between 1 July 2011 and 30 June 2012,and which included children with acute leukemia compared to children unharmed by neoplastic disease . Cases and controls were matched by age and gender. Our objective was to: - Describe the socio-occupational characteristics of the parents of children with acute leukemia. - Identify potential occupational factors implicated in the genesis of acute leukemia. Result: The number of acute leukemia cases in the Hematology Service and day hospital of the University Hospital of Farhat Hached during the study period was 66 cases divided into in 40 boys and 26 girls with a sex ratio of 1.53. Our cases and controls were matched by age and gender. The risk of incidence of leukemia in children from smoking fathers was higher (p = 0.02, OR = 2.24, IC = [1.11 - 4.52]). The risk of incidence of leukemia in children from alcoholic fathers was higher with p = 0,009, OR = 3.9; CI = [1.33 - 11.39]. After adjusting different variables, the difference persisted significantly with pa = 0.03 and ORa = 3.5; ICa = [1.09 -11.6]. 25.7 % of cases had a family history of blood disease and neoplasia, whereas no control presented that. The difference was statistically significant (p = 0.006), OR = 1.46, IC = [1.38 - 1.56]. The parental occupational exposures associated to the occurrence of acute leukemia in children were: - Pesticides with a statistically significant difference (p = 0.03), OR = 2.94, IC = [1.06 - 8.13]. This difference persisted after adjustment with different variables pa = 0.01, ORa 3.75; ICa = [1.27 - 11.03]. - Cement without a statistically non-significant difference (p = 0.2). This difference has become significant after adjustment with the different variables pa = 0.03; ORa = 2.67; ICa = [1.06 - 6.7]. Conclusion: Parental exposure to occupational risk factors may play a role in the pathogenesis of acute leukemia in children.Keywords: hematological malignancies, children, parents, occupational exposure
Procedia PDF Downloads 3208318 Analysis of a Self-Acting Air Journal Bearing: Effect of Dynamic Deformation of Bump Foil
Authors: H. Bensouilah, H. Boucherit, M. Lahmar
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A theoretical investigation on the effects of both steady-state and dynamic deformations of the foils on the dynamic performance characteristics of a self-acting air foil journal bearing operating under small harmonic vibrations is proposed. To take into account the dynamic deformations of foils, the perturbation method is used for determining the gas-film stiffness and damping coefficients for given values of excitation frequency, compressibility number, and compliance factor of the bump foil. The nonlinear stationary Reynolds’ equation is solved by means of the Galerkins’ finite element formulation while the finite differences method are used to solve the first order complex dynamic equations resulting from the perturbation of the nonlinear transient compressible Reynolds’ equation. The stiffness of a bump is uniformly distributed throughout the bearing surface (generation I bearing). It was found that the dynamic properties of the compliant finite length journal bearing are significantly affected by the compliance of foils especially when the dynamic deformation of foils is considered in addition to the static one by applying the principle of superposition.Keywords: elasto-aerodynamic lubrication, air foil bearing, steady-state deformation, dynamic deformation, stiffness and damping coefficients, perturbation method, fluid-structure interaction, Galerk infinite element method, finite difference method
Procedia PDF Downloads 3968317 Structural, Magnetic and Thermodynamic Investigation of Iridium Double Perovskites with Ir⁵⁺
Authors: Mihai I. Sturza, Laura T. Corredor, Kaustuv Manna, Gizem A. Cansever, Tushar Dey, Andrey Maljuk, Olga Kataeva, Sabine Wurmehl, Anja Wolter, Bernd Buchner
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Recently, the iridate double perovskite Sr₂YIrO₆ has attracted considerable attention due to the report of unexpected magnetism in this Ir⁵⁺ material, in which according to the Jeff model, a non-magnetic ground state is expected. Structural, magnetic and thermodynamic investigations of Sr₂YIrO₆ and Ba2YIrO6 single crystals, with emphasis on the temperature and magnetic field dependence of the specific heat will be presented. The single crystals were grown by using SrCl₂ and BaCl₂ as flux. Single-crystal X-ray diffraction measurements performed on several crystals from different preparation batches showed a high quality of the crystals, proven by the good internal consistency of the data collected using the full-sphere mode and an extremely low R factor. In agreement with the expected non-magnetic ground state of Ir⁵⁺ (5d4) in these iridates, no magnetic transition is observed down to 430 mK. Moreover, our results suggest that the low-temperature anomaly observed in the specific heat is not related to the onset of long-range magnetic order. Instead, it is identified as a Schottky anomaly caused by paramagnetic impurities present in the sample, of the order ofKeywords: double perovskites, iridates, self-flux grown synthesis, spin-orbit coupling
Procedia PDF Downloads 3328316 Optimal Location of Unified Power Flow Controller (UPFC) for Transient Stability: Improvement Using Genetic Algorithm (GA)
Authors: Basheer Idrees Balarabe, Aminu Hamisu Kura, Nabila Shehu
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As the power demand rapidly increases, the generation and transmission systems are affected because of inadequate resources, environmental restrictions and other losses. The role of transient stability control in maintaining the steady-state operation in the occurrence of large disturbance and fault is to describe the ability of the power system to survive serious contingency in time. The application of a Unified power flow controller (UPFC) plays a vital role in controlling the active and reactive power flows in a transmission line. In this research, a genetic algorithm (GA) method is applied to determine the optimal location of the UPFC device in a power system network for the enhancement of the power-system Transient Stability. Optimal location of UPFC has Significantly Improved the transient stability, the damping oscillation and reduced the peak over shoot. The GA optimization Technique proposed was iteratively searches the optimal location of UPFC and maintains the unusual bus voltages within the satisfy limits. The result indicated that transient stability is improved and achieved the faster steady state. Simulations were performed on the IEEE 14 Bus test systems using the MATLAB/Simulink platform.Keywords: UPFC, transient stability, GA, IEEE, MATLAB and SIMULINK
Procedia PDF Downloads 198315 Epidemiology of Healthcare-Associated Infections among Hematology/Oncology Patients: Results of a Prospective Incidence Survey in a Tunisian University Hospital
Authors: Ezzi Olfa, Bouafia Nabiha, Ammar Asma, Ben Cheikh Asma, Mahjoub Mohamed, Bannour Wadiaa, Achour Bechir, Khelif Abderrahim, Njah Mansour
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Background: In hematology/oncology, health care improvement has allowed increasingly aggressive management in diagnostic and therapeutic procedures. Nevertheless, these intensified procedures have been associated with higher risk of healthcare associated infections (HAIs). We undertook this study to estimate the burden of HAIs in the cancer patients in an onco -hematology unit in a Tunisian university hospital. Materials/Methods: A prospective, observational study, based on active surveillance for a period of 06 months from Mars through September 2016, was undertaken in the department of onco-hematology in a university hospital in Tunisia. Patients, who stayed in the unit for ≥ 48 h, were followed until hospital discharge. The Centers for Disease Control and Prevention criteria (CDC) for site-specific infections were used as standard definitions for HAIs. Results: One hundred fifty patients were included in the study. The gender distribution was 33.3% for girls and 66.6% boys. They have a mean age of 23.12 years (SD = 18.36 years). The main patient’s diagnosis is: Acute Lymphoblastic Leukemia (ALL): 48.7 %( n=73). The mean length of stay was 21 days +/- 18 days. Almost 8% of patients had an implantable port (n= 12), 34.9 % (n=52) had a lumber puncture and 42.7 % (n= 64) had a medullary puncture. Chemotherapy was instituted in 88% of patients (n=132). Eighty (53.3%) patients had neutropenia at admission. The incidence rate of HAIs was 32.66 % per patient; the incidence density was 15.73 per 1000 patient-days in the unit. Mortality rate was 9.3% (n= 14), and 50% of cases of death were caused by HAIs. The most frequent episodes of infection were: infection of skin and superficial mucosa (5.3%), pulmonary aspergillosis (4.6%), Healthcare associated pneumonia (HAP) (4%), Central venous catheter associated infection (4%), digestive infection (5%), and primary bloodstream infection (2.6%). Finally, fever of unknown origin (FUO) incidence rate was 14%. In case of skin and superficial infection (n= 8), 4 episodes were documented, and organisms implicated were Escherichia.coli, Geotricum capitatum and Proteus mirabilis. For pulmonary aspergillosis, 6 cases were diagnosed clinically and radiologically, and one was proved by positive aspergillus antigen in bronchial aspiration. Only one patient died due this infection. In HAP (6 cases), four episodes were diagnosed clinically and radiologically. No bacterial etiology was established in these cases. Two patients died due to HAP. For primary bloodstream infection (4 cases), implicated germs were Enterobacter cloacae, Geotricum capitatum, klebsiella pneumoniae, and Streptococcus pneumoniae. Conclusion: This type of prospective study is an indispensable tool for internal quality control. It is necessary to evaluate preventive measures and design control guides and strategies aimed to reduce the HAI’s rate and the morbidity and mortality associated with infection in a hematology/oncology unit.Keywords: cohort prospective studies, healthcare associated infections, hematology oncology department, incidence
Procedia PDF Downloads 3918314 Knowledge, Attitude, and Practice Regarding Standard Precautions in Medical Students of Rawalpindi Medical University, Pakistan; A Cross-Sectional Descriptive Study
Authors: Zainab Idrees Ahmad, Mahjabeen Qureshi, Zainab Hussain
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Standard precautions are a set of infection control practices used to prevent the transmission of diseases that can be acquired by contact with body fluids, non-intact skin, and mucous membranes. Lack of practice of SPs can result in a considerable increase in morbidity and mortality rates. Medical students (the future physicians) should have the highest knowledge of standard precautions to prevent the spread of nosocomial infections and ensure their safety as well. This study was designed. To assess the knowledge of medical students regarding standard precautions. And explore the attitude of medical students of MBBS in the third, fourth and final year towards standard precautions.: A descriptive cross-sectional study was conducted in the setting of Rawalpindi Medical University, Pakistan including the students of MBBS in their 3rd, 4th and final years. The study duration was from October 2022 to February 2023. The sample size calculated was 282 with a confidence interval of 95%. A questionnaire was structured utilizing the WHO guidelines on SPs assessing knowledge and attitude regarding hand hygiene, needle stick injury, use of gloves and mask, and sharp disposal. A total of 300 responses were received utilizing the technique of non-random convenience sampling. Data was analyzed using the latest version of SPSS.:Knowledge score regarding components of SPs, hand hygiene, and moments of hand hygiene was satisfactory. However, score regarding the use of PPE, needle stick injury, and sharp disposal was low. Almost all the students were compliant with the proper washing of hands but the observation of recommended time length was lacking. Compliance with the use of correct PPE and informing the supervisor upon getting a needle stick injury was low. This study signifies that medical students lack knowledge regarding standard precautions. This is alarming as this can be the vehicle for the spread of nosocomial infections. Proper training should be given to medical students to prevent the spread of hospital-acquired infections.Keywords: attitude, knowledge, medical students, standard precautions
Procedia PDF Downloads 1298313 Accessibility of Youth-Friendly Sexual and Reproductive Health Services to Secondary School Adolescents in Southern Cross River, Nigeria
Authors: Rosemary I. Eneji, Stephen Adi Odey, Edem Carole, Eucharia Nwagbara
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Sexual and reproductive health behaviors are the main causes of death, disability, and disease among adolescents in Nigeria. In this study, we determined the accessibility of youth-friendly sexual and reproductive health services to secondary school adolescents in southern Cross River state, Nigeria. Nineteen randomly selected public secondary schools across the seven local government areas in the zone were used. The respondents were four hundred senior secondary (classes SSI - SS3) students aged 15-19 years, comprising 63.7% females and 36.3% males. A 50-item structured questionnaire was used for the study. There was a strong influence of age and sex of adolescents, income and occupation of parents, knowledge and awareness of adolescents, and tradition on the accessibility and use of youth-friendly sexual and reproductive health services (YFSRHS) to the adolescents. The attitude of health workers towards accessibility was of little effect. Overall, youth-friendly sexual and reproductive health services were not easily accessible to adolescents in the study area. Thus, there is need to enforce adolescent reproductive health policies in the area. Training and use of trained caregivers and peer educators to attend to adolescents and the inclusion of adolescent reproductive health as a subject in the curriculum are strongly recommended.Keywords: youth, reproductive health, cross river state, secondary schools, Nigeria
Procedia PDF Downloads 748312 Disability Prevalence and Health among 60+ Population in India
Authors: Surendra Kumar Patel
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Disability is not just a health problem; it is a complex phenomenon, reflecting the interaction between features of a person’s age and physiology. Population ageing is a major demographic issue for India in the 21st century. Older population of India constituted 8% of total population, while 5.19% has affected by disability of older age group. Objective of the present research paper is to examine the state wise differential in disability among 60+ population and to access the health care of disabled population especially the 60+ disabled persons. The data sources of the present paper are census 2001 and 2011. For analyzing the state wise differentials by disability types and comparative advantage of data, rate, ratio, and percentage have been used. The Standardized Index of Diversity of Disability (SIDD) studies differential and diversity in disability. The results show that there are 5.19% persons have disability among 60+ population and sex differential not very significant, as it is 5.3 % of male and 5.05% in female in India but place of residence shows significant variation from 2001 to 2011 census. There is huge diversity in disability prevalence among 60+ in India, highest in Sikkim followed by Rajasthan, approximately, they comprise 11%, and the lowest found in Tamil Nadu as 2.53%. This huge gap in prevalence percentage shows the health care needs of highly prevailing states.Keywords: disability, Standardized Index of Diversity of Disability (SIDD), differential and diversity in disability, 60+ population
Procedia PDF Downloads 3818311 Development of High Quality Refractory Bricks from Fireclays for Industrial Applications
Authors: David E. Esezobor, Friday I. Apeh, Harrison O. Onovo, Ademola A. Agbeleye
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Available indigenous refractory bricks in Nigeria can only be used in the lining of furnaces for melting of cast iron operating at less than 1,400°C or in preheating furnaces due to their low refractoriness less than 1,500°C. The bricks crack and shatter on heating at 1350 to 1450°C. In this paper, a simple and adaptable technology of manufacturing high-quality refractory bricks from selected Nigerian clays for furnace linings was developed. Fireclays from Onibode, Owode-Ketu in Ogun State and Kwoi in Kaduna State were crushed, ground, and sieved into various grain sizes using standard techniques. The pulverized clays were blended with alumina in various mix ratios and indurated in the furnace at 900 – 16000C. Their chemical, microstructure and mineralogical properties were characterized using atomic absorption spectrophotometry, scanning electron microscopy and x-ray diffraction spectrometry respectively. The mineralogical and spectrochemical analyses suggested that the clays are of siliceous alumino-silicate and acidic in nature. The appropriate blending of fireclays with alumina provided the tremendous improvement in the refractoriness of the bricks and other acceptable service properties comparable with imported refractory bricks. The change in microstructure from pseudo-hexagonal grains to equiaxed grains of well – ordered sequence of structural layers could be responsible for the improved properties.Keywords: alumina, furnace, industry, manufacturing, refractoriness
Procedia PDF Downloads 2588310 From Cascade to Cluster School Model of Teachers’ Professional Development Training Programme: Nigerian Experience, Ondo State: A Case Study
Authors: Oloruntegbe Kunle Oke, Alake Ese Monica, Odutuyi Olubu Musili
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This research explores the differing effectiveness of cascade and cluster models in professional development programs for educators in Ondo State, Nigeria. The cascade model emphasizes a top-down approach, where training is cascaded from expert trainers to lower levels of teachers. In contrast, the cluster model, a bottom-up approach, fosters collaborative learning among teachers within specific clusters. Through a review of the literature and empirical studies of the implementations of the former in two academic sessions followed by the cluster model in another two, the study examined their effectiveness on teacher development, productivity and students’ achievements. The study also drew a comparative analysis of the strengths and weaknesses associated with each model, considering factors such as scalability, cost-effectiveness, adaptability in various contexts, and sustainability. 2500 teachers from Ondo State Primary Schools participated in the cascade with intensive training in five zones for a week each in two academic sessions. On the other hand, 1,980 and 1,663 teachers in 52 and 34 clusters, respectively, were in the first and the following session. The programs were designed for one week of rigorous training of teachers by facilitators in the former while the latter was made up of four components: sit-in-observation, need-based assessment workshop, pre-cluster and the actual cluster meetings in addition to sensitization, and took place one day a week for ten weeks. Validated Cluster Impact Survey Instruments, CISI and Teacher’s Assessment Questionnaire (TAQ) were administered to ascertain the effectiveness of the models during and after implementation. The findings from the literature detailed specific effectiveness, strengths and limitations of each approach, especially the potential for inconsistencies and resistance to change. Findings from the data collected revealed the superiority of the cluster model. Response to TAQ equally showed content knowledge and skill update in both but were more sustained in the cluster model. Overall, the study contributes to the ongoing discourse on effective strategies for improving teacher training and enhancing student outcomes, offering practical recommendations for the development and implementation of future professional development projects.Keywords: cascade model, cluster model, teachers’ development, productivity, students’ achievement
Procedia PDF Downloads 498309 Economic Analysis of Cassava Value Chain by Farmers in Ilesa West Local Government Area of Osun State
Authors: Maikasuwa Mohammed Abubakar, Okebiorun Ola, M. H. Sidi, Ala Ahmed Ladan, Ango Aabdullahi Kamba
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The study examines the economic analysis of cassava value chain by farmers in Ilesa West Local Government Area of Osun State. Simple random sampling technique was used to collect data from 200 respondents from purposively selected wards in the L.G.A. The data collected were analyzed using budgetary analysis and value addition model. The result shows that an average total cost incurred by the input dealers was ₦9,062,127.74 while the average net profit realized was ₦1,038,102.40. Other actors such as producers, processors and marketers incurred an average total cost of ₦23,324.00, ₦130,177.00 and ₦523,755.00 per production season, respectively and the average net profit realized was ₦102,614.00 for cassava producers, ₦51,131.00 for cassava processors and ₦79,045.00 for cassava marketers during cassava production season. Further analysis shows the rate of investment for cassava input dealers was ₦0.1, for cassava producers was ₦4.4, for cassava processors were ₦0.40 and for cassava marketers was ₦0.20. This indicated that rate of return on cassava was higher in cassava production than in others corridors along the value chain of cassava. However, value added the cassava producers (₦102,536.16/season) was the highest when compared with value added by cassava processors (₦51,853.82/season) and cassava marketers (₦100,885.56/season).Keywords: Cassava, value chain, Ilesa West, Nigeria
Procedia PDF Downloads 3348308 Genetic Parameters as Indicators of Sustainability and Diversity of Schinus terebinthifolius Populations in the Riparian Area of the São Francisco River
Authors: Renata Silva-Mann, Sheila Valéria Álvares Carvalho, Robério Anastácio Ferreira, Laura Jane Gomes
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There is growing interest in defining indicators of sustainability, which are important for monitoring the conservation of native forests, particularly in areas of permanent protection. These indicators are references for assessing the state of the forest and the status of the depredated area and its ability to maintain species populations. The aim of the present study was to select genetic parameters as indicators of sustainability for Schinus terebinthifolius Raddi. Fragments located in riparian areas between the Sergipe and Alagoas States in Brazil. This species has been exploited for traditional communities, which represent 20% of the incoming. This study was carried out using the indicators suggested by the Organization for Economic Cooperation and Development, which were identified as Driving-Pressure-State-Impact-Response (DPSIR) factors. The genetic parameters were obtained in five populations located on the shores and islands of the São Francisco River, one of the most important rivers in Brazil. The framework for Schinus conservation suggests seventeen indicators of sustainability. In accordance with genetic parameters, the populations are isolated, and these genetic parameters can be used to monitor the sustainability of those populations in riparian area with the aim of defining strategies for forest restoration.Keywords: alleles, molecular markers, genetic diversity, biodiversity
Procedia PDF Downloads 3058307 A Dual-Mode Infinite Horizon Predictive Control Algorithm for Load Tracking in PUSPATI TRIGA Reactor
Authors: Mohd Sabri Minhat, Nurul Adilla Mohd Subha
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The PUSPATI TRIGA Reactor (RTP), Malaysia reached its first criticality on June 28, 1982, with power capacity 1MW thermal. The Feedback Control Algorithm (FCA) which is conventional Proportional-Integral (PI) controller, was used for present power control method to control fission process in RTP. It is important to ensure the core power always stable and follows load tracking within acceptable steady-state error and minimum settling time to reach steady-state power. At this time, the system could be considered not well-posed with power tracking performance. However, there is still potential to improve current performance by developing next generation of a novel design nuclear core power control. In this paper, the dual-mode predictions which are proposed in modelling Optimal Model Predictive Control (OMPC), is presented in a state-space model to control the core power. The model for core power control was based on mathematical models of the reactor core, OMPC, and control rods selection algorithm. The mathematical models of the reactor core were based on neutronic models, thermal hydraulic models, and reactivity models. The dual-mode prediction in OMPC for transient and terminal modes was based on the implementation of a Linear Quadratic Regulator (LQR) in designing the core power control. The combination of dual-mode prediction and Lyapunov which deal with summations in cost function over an infinite horizon is intended to eliminate some of the fundamental weaknesses related to MPC. This paper shows the behaviour of OMPC to deal with tracking, regulation problem, disturbance rejection and caters for parameter uncertainty. The comparison of both tracking and regulating performance is analysed between the conventional controller and OMPC by numerical simulations. In conclusion, the proposed OMPC has shown significant performance in load tracking and regulating core power for nuclear reactor with guarantee stabilising in the closed-loop.Keywords: core power control, dual-mode prediction, load tracking, optimal model predictive control
Procedia PDF Downloads 1638306 JaCoText: A Pretrained Model for Java Code-Text Generation
Authors: Jessica Lopez Espejel, Mahaman Sanoussi Yahaya Alassan, Walid Dahhane, El Hassane Ettifouri
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Pretrained transformer-based models have shown high performance in natural language generation tasks. However, a new wave of interest has surged: automatic programming language code generation. This task consists of translating natural language instructions to a source code. Despite the fact that well-known pre-trained models on language generation have achieved good performance in learning programming languages, effort is still needed in automatic code generation. In this paper, we introduce JaCoText, a model based on Transformer neural network. It aims to generate java source code from natural language text. JaCoText leverages the advantages of both natural language and code generation models. More specifically, we study some findings from state of the art and use them to (1) initialize our model from powerful pre-trained models, (2) explore additional pretraining on our java dataset, (3) lead experiments combining the unimodal and bimodal data in training, and (4) scale the input and output length during the fine-tuning of the model. Conducted experiments on CONCODE dataset show that JaCoText achieves new state-of-the-art results.Keywords: java code generation, natural language processing, sequence-to-sequence models, transformer neural networks
Procedia PDF Downloads 2888305 Comparative Study of Various Wall Finishes in Buildings in Ondo State, Nigeria
Authors: Ayodele Oluwole Alejo
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Wall finishes are the term to describe an application over a wall surface to provide a suitable surface. Wall finishes are smelt, touched and seen by building occupiers even colour and design affects the user psychology and the atmosphere of our building. Building users/owners seem not to recognize the function of various wall finishes in building and factors to be considered in selecting them suitable for the type and purpose of proposed buildings. Therefore, defects such as deterioration, dampness, and stain may occur when comparisons of wall finishes are not made before the selection of appropriate materials at the design stage with knowledge of the various factors that may hinder the performance or maintenance culture of proposed building of a particular location. This research work investigates and compares various wall finishes in building. Buildings in Ondo state, Nigeria were used as the target area to conduct the research works. The factors bearing on various wall finishes were analyzed to find out their individual and collective impact using suitable analytical tools. The findings revealed that paint with high percentage score was the most preferred wall finishes, whereas wall paper was ranked the least by the respondent findings, Factors considered most in the selection of wall finishes was durability with the highest ranking percentage and least was the cost. The study recommends that skilled worker should carry out operations, quality product should be used and all of wall finishes and materials should be considered before selection.Keywords: building, construction, design, finishes, wall
Procedia PDF Downloads 1408304 Broadening the Public Sphere: Examining the Role of Community Radio in Fostering Participatory Democracy in Selected Communities in Ondo State, Nigeria
Authors: John Ibanga
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Since May 1999, when Nigeria returned to uninterrupted democratic rule, there have been various attempts by successive governments at committing themselves to democratic ideals. Such efforts include a revision of communication policies after repeated calls by civil society organisations, development partners, researchers, and academics to allow not only the commencement of campus radio broadcasting but also the takeoff of community radio broadcasting. Thus, in 2015, operating licenses were granted to several communities spread across the six geopolitical zones in the country for the establishment of community radio stations culminating in the establishment of the first community radio in Nigeria on July 17, 2015. And, since citizens’ involvement in policy matters and governance is one of the tenets of participatory democracy, it becomes imperative to investigate how the emerging community radio sector in Nigeria is facilitating participatory democracy among Nigerians, even in the face of attempts by the present government to silence all dissenting voices. This study, therefore, examines how residents in Ondo State, Southwest Nigeria, are utilising programmes on Ejule Nen and Kakaaki community radio stations in Ondo State, Nigeria, to deepen participatory democracy. Much of the existing studies on the role of community radio in participatory democracy and citizens' engagement efforts miss out on Nigeria because of the delayed implementation of community radio policy in Nigeria being Africa’s most populous nation as well as a major player in the affairs of the African continent. While the participatory communication and communication infrastructure theories were used as framework, data were collected from in-depth interviews with staff of the community radio station and community leaders, focus group discussions with the community residents, and qualitative content analysis of programmes on the station. The residents used the community radio stations as platforms for demanding accountability from government, mobilising resources for the execution of a number of community projects, promoting credible electoral practices, and influencing the implementation of free education policy in their communities. Hence the community radio stations became the reliable and authoritative voices of residents for participating in the public sphere and, generally, the democratic process.Keywords: community, community radio, democracy, participatory democracy
Procedia PDF Downloads 1288303 A Xenon Mass Gauging through Heat Transfer Modeling for Electric Propulsion Thrusters
Authors: A. Soria-Salinas, M.-P. Zorzano, J. Martín-Torres, J. Sánchez-García-Casarrubios, J.-L. Pérez-Díaz, A. Vakkada-Ramachandran
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The current state-of-the-art methods of mass gauging of Electric Propulsion (EP) propellants in microgravity conditions rely on external measurements that are taken at the surface of the tank. The tanks are operated under a constant thermal duty cycle to store the propellant within a pre-defined temperature and pressure range. We demonstrate using computational fluid dynamics (CFD) simulations that the heat-transfer within the pressurized propellant generates temperature and density anisotropies. This challenges the standard mass gauging methods that rely on the use of time changing skin-temperatures and pressures. We observe that the domes of the tanks are prone to be overheated, and that a long time after the heaters of the thermal cycle are switched off, the system reaches a quasi-equilibrium state with a more uniform density. We propose a new gauging method, which we call the Improved PVT method, based on universal physics and thermodynamics principles, existing TRL-9 technology and telemetry data. This method only uses as inputs the temperature and pressure readings of sensors externally attached to the tank. These sensors can operate during the nominal thermal duty cycle. The improved PVT method shows little sensitivity to the pressure sensor drifts which are critical towards the end-of-life of the missions, as well as little sensitivity to systematic temperature errors. The retrieval method has been validated experimentally with CO2 in gas and fluid state in a chamber that operates up to 82 bar within a nominal thermal cycle of 38 °C to 42 °C. The mass gauging error is shown to be lower than 1% the mass at the beginning of life, assuming an initial tank load at 100 bar. In particular, for a pressure of about 70 bar, just below the critical pressure of CO2, the error of the mass gauging in gas phase goes down to 0.1% and for 77 bar, just above the critical point, the error of the mass gauging of the liquid phase is 0.6% of initial tank load. This gauging method improves by a factor of 8 the accuracy of the standard PVT retrievals using look-up tables with tabulated data from the National Institute of Standards and Technology.Keywords: electric propulsion, mass gauging, propellant, PVT, xenon
Procedia PDF Downloads 347