Search results for: stress analysis
19863 Analysis of High Resolution Seismic Reflection Data to Identify Different Regional Lithologies of the Zaria Batholith Located in the Basement Complex of North Central Nigeria
Authors: Collins C. Chiemeke, A. Onugba, P. Sule
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High resolution seismic reflection has recently been carried out on Zaria batholith, with the aim of characterizing the granitic Zaria batholiths in terms of its lithology. The geology of the area has revealed that the older granite outcrops in the vicinity of Zaria are exposures of a syntectonics to late-tectonic granite batholiths which intruded a crystalline gneissic basement during the Pan-African Orogeny. During the data acquisition the geophone were placed at interval of 1 m, variable offset of 1 and 10 m was used. The common midpoint (CMP) method with 12 fold coverage was employed for the survey. Analysis of the generated 3D surface of the p wave velocities from different profiles for densities and bulk modulus revealed that the rock material is more consolidated in South East part of the batholith and less consolidated in the North Western part. This was in conformity with earlier identified geology of the area, with the South Eastern part majorly of granitic outcrop, while the North Western part is characterized with the exposure of gneisses and thick overburden cover. The difference in lithology was also confirmed by the difference in seismic sections and Arial satellite photograph. Hence two major lithologies were identified, the granitic and gneisses complex which are characterized by gradational boundaries.Keywords: basement complex, batholith, high resolution, lithologies, seismic reflection
Procedia PDF Downloads 29619862 Short and Long Crack Growth Behavior in Ferrite Bainite Dual Phase Steels
Authors: Ashok Kumar, Shiv Brat Singh, Kalyan Kumar Ray
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There is growing awareness to design steels against fatigue damage Ferrite martensite dual-phase steels are known to exhibit favourable mechanical properties like good strength, ductility, toughness, continuous yielding, and high work hardening rate. However, dual-phase steels containing bainite as second phase are potential alternatives for ferrite martensite steels for certain applications where good fatigue property is required. Fatigue properties of dual phase steels are popularly assessed by the nature of variation of crack growth rate (da/dN) with stress intensity factor range (∆K), and the magnitude of fatigue threshold (∆Kth) for long cracks. There exists an increased emphasis to understand not only the long crack fatigue behavior but also short crack growth behavior of ferrite bainite dual phase steels. The major objective of this report is to examine the influence of microstructures on the short and long crack growth behavior of a series of developed dual-phase steels with varying amounts of bainite and. Three low carbon steels containing Nb, Cr and Mo as microalloying elements steels were selected for making ferrite-bainite dual-phase microstructures by suitable heat treatments. The heat treatment consisted of austenitizing the steel at 1100°C for 20 min, cooling at different rates in air prior to soaking these in a salt bath at 500°C for one hour, and finally quenching in water. Tensile tests were carried out on 25 mm gauge length specimens with 5 mm diameter using nominal strain rate 0.6x10⁻³ s⁻¹ at room temperature. Fatigue crack growth studies were made on a recently developed specimen configuration using a rotating bending machine. The crack growth was monitored by interrupting the test and observing the specimens under an optical microscope connected to an Image analyzer. The estimated crack lengths (a) at varying number of cycles (N) in different fatigue experiments were analyzed to obtain log da/dN vs. log °∆K curves for determining ∆Kthsc. The microstructural features of these steels have been characterized and their influence on the near threshold crack growth has been examined. This investigation, in brief, involves (i) the estimation of ∆Kthsc and (ii) the examination of the influence of microstructure on short and long crack fatigue threshold. The maximum fatigue threshold values obtained from short crack growth experiments on various specimens of dual-phase steels containing different amounts of bainite are found to increase with increasing bainite content in all the investigated steels. The variations of fatigue behavior of the selected steel samples have been explained with the consideration of varying amounts of the constituent phases and their interactions with the generated microstructures during cyclic loading. Quantitative estimation of the different types of fatigue crack paths indicates that the propensity of a crack to pass through the interfaces depends on the relative amount of the microstructural constituents. The fatigue crack path is found to be predominantly intra-granular except for the ones containing > 70% bainite in which it is predominantly inter-granular.Keywords: bainite, dual phase steel, fatigue crack growth rate, long crack fatigue threshold, short crack fatigue threshold
Procedia PDF Downloads 20319861 Measuring Fluctuating Asymmetry in Human Faces Using High-Density 3D Surface Scans
Authors: O. Ekrami, P. Claes, S. Van Dongen
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Fluctuating asymmetry (FA) has been studied for many years as an indicator of developmental stability or ‘genetic quality’ based on the assumption that perfect symmetry is ideally the expected outcome for a bilateral organism. Further studies have also investigated the possible link between FA and attractiveness or levels of masculinity or femininity. These hypotheses have been mostly examined using 2D images, and the structure of interest is usually presented using a limited number of landmarks. Such methods have the downside of simplifying and reducing the dimensionality of the structure, which will in return increase the error of the analysis. In an attempt to reach more conclusive and accurate results, in this study we have used high-resolution 3D scans of human faces and have developed an algorithm to measure and localize FA, taking a spatially-dense approach. A symmetric spatially dense anthropometric mask with paired vertices is non-rigidly mapped on target faces using an Iterative Closest Point (ICP) registration algorithm. A set of 19 manually indicated landmarks were used to examine the precision of our mapping step. The protocol’s accuracy in measurement and localizing FA is assessed using simulated faces with known amounts of asymmetry added to them. The results of validation of our approach show that the algorithm is perfectly capable of locating and measuring FA in 3D simulated faces. With the use of such algorithm, the additional captured information on asymmetry can be used to improve the studies of FA as an indicator of fitness or attractiveness. This algorithm can especially be of great benefit in studies of high number of subjects due to its automated and time-efficient nature. Additionally, taking a spatially dense approach provides us with information about the locality of FA, which is impossible to obtain using conventional methods. It also enables us to analyze the asymmetry of a morphological structures in a multivariate manner; This can be achieved by using methods such as Principal Components Analysis (PCA) or Factor Analysis, which can be a step towards understanding the underlying processes of asymmetry. This method can also be used in combination with genome wide association studies to help unravel the genetic bases of FA. To conclude, we introduced an algorithm to study and analyze asymmetry in human faces, with the possibility of extending the application to other morphological structures, in an automated, accurate and multi-variate framework.Keywords: developmental stability, fluctuating asymmetry, morphometrics, 3D image processing
Procedia PDF Downloads 14019860 Reliability-Centered Maintenance Application for the Development of Maintenance Strategy for a Cement Plant
Authors: Nabil Hameed Al-Farsi
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This study’s main goal is to develop a model and a maintenance strategy for a cement factory called Arabian Cement Company, Rabigh Plant. The proposed work here depends on Reliability centric maintenance approach to develop a strategy and maintenance schedule that ensures increasing the reliability of the production system components, thus ensuring continuous productivity. The cost-effective maintenance of the plant’s dependability performance is the key goal of durability-based maintenance is. The cement plant consists of 7 important steps, so, developing a maintenance plan based on Reliability centric maintenance (RCM) method is made up of 10 steps accordingly starting from selecting units and data until performing and updating the model. The processing unit chosen for the analysis of this case is the calcinatory unit regarding model’s validation and the Travancore Titanium Products Ltd (TTP) using the claimed data history acquired from the maintenance department maintenance from the mentioned company. After applying the proposed model, the results of the maintenance simulation justified the plant's existing scheduled maintenance policy being reconsidered. Results represent the need for preventive maintenance for all Class A criticality equipment instead of the planned maintenance and the breakdown one for all other equipment depends on its criticality and an FMEA report. Consequently, the additional cost of preventive maintenance would be offset by the cost savings from breakdown maintenance for the remaining equipment.Keywords: engineering, reliability, strategy, maintenance, failure modes, effects and criticality analysis (FMEA)
Procedia PDF Downloads 17119859 Finite Element Analysis of Raft Foundation on Various Soil Types under Earthquake Loading
Authors: Qassun S. Mohammed Shafiqu, Murtadha A. Abdulrasool
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The design of shallow foundations to withstand different dynamic loads has given considerable attention in recent years. Dynamic loads may be due to the earthquakes, pile driving, blasting, water waves, and machine vibrations. But, predicting the behavior of shallow foundations during earthquakes remains a difficult task for geotechnical engineers. A database for dynamic and static parameters for different soils in seismic active zones in Iraq is prepared which has been collected from geophysical and geotechnical investigation works. Then, analysis of a typical 3-D soil-raft foundation system under earthquake loading is carried out using the database. And a parametric study has been carried out taking into consideration the influence of some parameters on the dynamic behavior of the raft foundation, such as raft stiffness, damping ratio as well as the influence of the earthquake acceleration-time records. The results of the parametric study show that the settlement caused by the earthquake can be decreased by about 72% with increasing the thickness from 0.5 m to 1.5 m. But, it has been noticed that reduction in the maximum bending moment by about 82% was predicted by decreasing the raft thickness from 1.5 m to 0.5 m in all sites model. Also, it has been observed that the maximum lateral displacement, the maximum vertical settlement and the maximum bending moment for damping ratio 0% is about 14%, 20%, and 18% higher than that for damping ratio 7.5%, respectively for all sites model.Keywords: shallow foundation, seismic behavior, raft thickness, damping ratio
Procedia PDF Downloads 14819858 Determination of Surface Deformations with Global Navigation Satellite System Time Series
Authors: Ibrahim Tiryakioglu, Mehmet Ali Ugur, Caglar Ozkaymak
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The development of GNSS technology has led to increasingly widespread and successful applications of GNSS surveys for monitoring crustal movements. However, multi-period GPS survey solutions have not been applied in monitoring vertical surface deformation. This study uses long-term GNSS time series that are required to determine vertical deformations. In recent years, the surface deformations that are parallel and semi-parallel to Bolvadin fault have occurred in Western Anatolia. These surface deformations have continued to occur in Bolvadin settlement area that is located mostly on alluvium ground. Due to these surface deformations, a number of cracks in the buildings located in the residential areas and breaks in underground water and sewage systems have been observed. In order to determine the amount of vertical surface deformations, two continuous GNSS stations have been established in the region. The stations have been operating since 2015 and 2017, respectively. In this study, GNSS observations from the mentioned two GNSS stations were processed with GAMIT/GLOBK (GNSS Analysis Massachusetts Institute of Technology/GLOBal Kalman) program package to create a coordinate time series. With the time series analyses, the GNSS stations’ behavior models (linear, periodical, etc.), the causes of these behaviors, and mathematical models were determined. The study results from the time series analysis of these two 2 GNSS stations shows approximately 50-80 mm/yr vertical movement.Keywords: Bolvadin fault, GAMIT, GNSS time series, surface deformations
Procedia PDF Downloads 16519857 Impact of Glycation on Proteomics of Human Serum Albumin: Relevance to Diabetes Associated Pathologies
Authors: Alok Raghav, Jamal Ahmad
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Background: Serum albumin glycation and advanced glycation end products (AGE) formation correlates in diabetes and its associated complications. Extensive modified human serum albumin is used to study the biochemical, electrochemical and functional properties in hyperglycemic environment with relevance to diabetes. We evaluate Spectroscopic, side chain modifications, amino acid analysis, biochemical and functional group properties in four glucose modified samples. Methods: A series four human serum albumin samples modified with glucose was characterized in terms of amino acid analysis, spectroscopic properties and side chain modifications. The diagnostic technique employed incorporates UV Spectroscopy, Fluorescence Spectroscopy, biochemical assays for side chain modifications, amino acid estimations, electrochemical and optical characterstic of glycated albumin. Conclusion: Glucose modified human serum albumin confers AGEs formation alters biochemical, electrochemical, optical, and functional property that depend on the reactivity of glucose and its concentration used for in-vitro glycation. A biochemical, electrochemical, optical, and functional characterization of modified albumin in-vitro produced AGE product that will be useful to interpret the complications and pathophysiological significance in diabetes.Keywords: human serum albumin, glycated albumin, adavanced glycation end products, associated pathologies
Procedia PDF Downloads 40119856 Effect of Different Contaminants on Mineral Insulating Oil Characteristics
Authors: H. M. Wilhelm, P. O. Fernandes, L. P. Dill, C. Steffens, K. G. Moscon, S. M. Peres, V. Bender, T. Marchesan, J. B. Ferreira Neto
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Deterioration of insulating oil is a natural process that occurs during transformers operation. However, this process can be accelerated by some factors, such as oxygen, high temperatures, metals and, moisture, which rapidly reduce oil insulating capacity and favor transformer faults. Parts of building materials of a transformer can be degraded and yield soluble compounds and insoluble particles that shorten the equipment life. Physicochemical tests, dissolved gas analysis (including propane, propylene and, butane), volatile and furanic compounds determination, besides quantitative and morphological analyses of particulate are proposed in this study in order to correlate transformers building materials degradation with insulating oil characteristics. The present investigation involves tests of medium temperature overheating simulation by means of an electric resistance wrapped with the following materials immersed in mineral insulating oil: test I) copper, tin, lead and, paper (heated at 350-400 °C for 8 h); test II) only copper (at 250 °C for 11 h); and test III) only paper (at 250 °C for 8 h and at 350 °C for 8 h). A different experiment is the simulation of electric arc involving copper, using an electric welding machine at two distinct energy sets (low and high). Analysis results showed that dielectric loss was higher in the sample of test I, higher neutralization index and higher values of hydrogen and hydrocarbons, including propane and butane, were also observed. Test III oil presented higher particle count, in addition, ferrographic analysis revealed contamination with fibers and carbonized paper. However, these particles had little influence on the oil physicochemical parameters (dielectric loss and neutralization index) and on the gas production, which was very low. Test II oil showed high levels of methane, ethane, and propylene, indicating the effect of metal on oil degradation. CO2 and CO gases were formed in the highest concentration in test III, as expected. Regarding volatile compounds, in test I acetone, benzene and toluene were detected, which are oil oxidation products. Regarding test III, methanol was identified due to cellulose degradation, as expected. Electric arc simulation test showed the highest oil oxidation in presence of copper and at high temperature, since these samples had huge concentration of hydrogen, ethylene, and acetylene. Particle count was also very high, showing the highest release of copper in such conditions. When comparing high and low energy, the first presented more hydrogen, ethylene, and acetylene. This sample had more similar results to test I, pointing out that the generation of different particles can be the cause for faults such as electric arc. Ferrography showed more evident copper and exfoliation particles than in other samples. Therefore, in this study, by using different combined analytical techniques, it was possible to correlate insulating oil characteristics with possible contaminants, which can lead to transformers failure.Keywords: Ferrography, gas analysis, insulating mineral oil, particle contamination, transformer failures
Procedia PDF Downloads 22519855 The Contribution of the Livestock Marketing Programme in Improving Household Food Security in Communal Areas of Umzimkhulu Local Municipality, Kwa-Zulu Natal
Authors: Sibongiseni Peacock, Denver Naidoo, Sikhalazo Dube
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The study investigates the impact of the National Red Meat Development Programme on household food security in rural areas of uMzimkhulu. Self-administered questionnaires were employed to gather data from 77 smallholder beef farmers participating in the St. Paul feedlot project. Data analysis utilized the Household Food Insecurity Access Scale (HFIAS) developed by USAID to assess the household food security status of St. Paul feedlot beneficiaries, with descriptive statistics employed for result analysis. Findings indicate that the majority (80.50%) of beneficiaries experienced food insecurity, while (19.50%) were classified as food secure, with most participants falling within the category of moderate food insecurity. Food insecurity predominantly stemmed from challenges faced by farmers unable to sell their cattle or whose cattle were not market-ready due to bureaucratic obstacles hindering the programme. Farmers identified feed shortages as the primary constraint, resulting in missed income opportunities. These findings underscore the critical need to address feed challenges and bureaucratic barriers to enhance the efficacy of the National Red Meat Development Programme in promoting household food security in rural areas.Keywords: National Red Meat Development, household food security, St. Paul feedlot, livestock, HFIAS
Procedia PDF Downloads 5519854 The Impact of Autonomous Driving on Cities of the Future: A Literature Review
Authors: Maximilian A. Richter
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The public authority needs to understand the role and impacts of autonomous vehicle (AV) on the mobility system. At present, however, research shows that the impact of AV on cities varies. As a consequence, it is difficult to make recommendations to policymakers on how they should prepare for the future when so much remains unknown about this technology. The study aims to provide an overview of the literature on how autonomous vehicles will affect the cities and traffic of the future. To this purpose, the most important studies are first selected, and their results summarized. Further on, it will be clarified which advantages AV have for cities and how it can lead to an improvement in the current problems/challenges of cities. To achieve the research aim and objectives, this paper approaches a literature review. For this purpose, in a first step, the most important studies are extracted. This is limited to studies that are peer-reviewed and have been published in high-ranked journals such as the Journal of Transportation: Part A. In step 2, the most important key performance indicator (KPIs) (such as traffic volume or energy consumption) are selected from the literature research. Due to the fact that different terms are used in the literature for similar statements/KPIs, these must first be clustered. Furthermore, for each cluster, the changes from the respective studies are compiled, as well as their survey methodology. In step 3, a sensitivity analysis per cluster is made. Here, it will be analyzed how the different studies come to their findings and on which assumptions, scenarios, and methods these calculations are based. From the results of the sensitivity analysis, the success factors for the implementation of autonomous vehicles are drawn, and statements are made under which conditions AVs can be successful.Keywords: autonomous vehicles, city of the future, literature review, traffic simulations
Procedia PDF Downloads 10619853 An Appraisal of Blended Learning Approach for English Language Teaching in Saudi Arabia
Authors: H. Alqunayeer, S. Zamir
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Blended learning, an ideal amalgamation of online learning and face to face traditional approach is a new approach that may result in outstanding outcomes in the realm of teaching and learning. The dexterity and effectiveness offered by e-learning experience cannot be guaranteed in a traditional classroom, whereas one-to-one interaction the essential element of learning that can only be found in a traditional classroom. In recent years, a spectacular expansion in the incorporation of technology in language teaching and learning is observed in many universities of Saudi Arabia. Some universities recognize the importance of blending face-to-face with online instruction in language pedagogy, Qassim University is one of the many universities adopting Blackboard Learning Management system (LMS). The university has adopted this new mode of teaching/learning in year 2015. Although the experience is immature; however great pedagogical transformations are anticipated in the university through this new approach. This paper examines the role of blended language learning with particular reference to the influence of Blackboard Learning Management System on the development of English language learning for EFL learners registered in Bachelors of English language program. This paper aims at exploring three main areas: (i) the present status of Blended learning in the educational process in Saudi Arabia especially in Qassim University by providing a survey report on the number of training courses on Blackboard LMS conducted for the male and female teachers at various colleges of Qassim University, (ii) a survey on teachers perception about the utility, application and the outcome of using blended Learning approach in teaching English language skills courses, (iii) the students’ views on the efficiency of Blended learning approach in learning English language skills courses. Besides, analysis of students’ limitations and challenges related to the experience of blended learning via Blackboard, the suggestion and recommendations offered by the language learners have also been thought-out. The study is empirical in nature. In order to gather data on the afore mentioned areas survey questionnaire method has been used: in order to study students’ perception, a 5 point Likert-scale questionnaire has been distributed to 200 students of English department registered in Bachelors in English program (level 5 through level 8). Teachers’ views have been surveyed with the help of interviewing 25 EFL teachers skilled in using Blackboard LMS in their lectures. In order to ensure the validity and reliability of questionnaire, the inter-rater approach and Cronbach’s Alpha analysis have been used respectively. Analysis of variance (ANOVA) has been used to analyze the students’ perception about the productivity of the Blended approach in learning English language skills. The analysis of feedback by Saudi teachers and students about the usefulness, ingenuity, and productivity of Blended Learning via Blackboard LMS highlights the need of encouraging and expanding the implementation of this new approach into the field of English language teaching in Saudi Arabia, in order to augment congenial learning aura. Furthermore, it is hoped that the propositions and practical suggestions offered by the study will be functional for other similar learning environments.Keywords: blended learning, black board learning management system, English as foreign language (EFL) learners, EFL teachers
Procedia PDF Downloads 15619852 Expression Profiling of Chlorophyll Biosynthesis Pathways in Chlorophyll B-Lacking Mutants of Rice (Oryza sativa L.)
Authors: Khiem M. Nguyen, Ming C. Yang
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Chloroplast pigments are extremely important during photosynthesis since they play essential roles in light absorption and energy transfer. Therefore, understanding the efficiency of chlorophyll (Chl) biosynthesis could facilitate enhancement in photo-assimilates accumulation, and ultimately, in crop yield. The Chl-deficient mutants have been used extensively to study the Chl biosynthetic pathways and the biogenesis of the photosynthetic apparatus. Rice (Oryza sativa L.) is one of the most leading food crops, serving as staple food for many parts of the world. To author’s best knowledge, Chl b–lacking rice has been found; however the molecular mechanism of Chl biosynthesis still remains unclear compared to wild-type rice. In this study, the ultrastructure analysis, photosynthetic properties, and transcriptome profile of wild-type rice (Norin No.8, N8) and its Chl b-lacking mutant (Chlorina 1, C1) were examined. The finding concluded that total Chl content and Chl b content in the C1 leaves were strongly reduced compared to N8 leaves, suggesting that reduction in the total Chl content contributes to leaf color variation at the physiological level. Plastid ultrastructure of C1 possessed abnormal thylakoid membranes with loss of starch granule, large number of vesicles, and numerous plastoglobuli. The C1 rice also exhibited thinner stacked grana, which was caused by a reduction in the number of thylakoid membranes per granum. Thus, the different Chl a/b ratio of C1 may reflect the abnormal plastid development and function. Transcriptional analysis identified 23 differentially expressed genes (DEGs) and 671 transcription factors (TFs) that were involved in Chl metabolism, chloroplast development, cell division, and photosynthesis. The transcriptome profile and DEGs revealed that the gene encoding PsbR (PSII core protein) was down-regulated, therefore suggesting that the lower in light-harvesting complex proteins are responsible for the lower photosynthetic capacity in C1. In addition, expression level of cell division protein (FtsZ) genes were significantly reduced in C1, causing chloroplast division defect. A total of 19 DEGs were identified based on KEGG pathway assignment involving Chl biosynthesis pathway. Among these DEGs, the GluTR gene was down-regulated, whereas the UROD, CPOX, and MgCH genes were up-regulated. Observation through qPCR suggested that later stages of Chl biosynthesis were enhanced in C1, whereas the early stages were inhibited. Plastid structure analysis together with transcriptomic analysis suggested that the Chl a/b ratio was amplified both by the reduction in Chl contents accumulation, owning to abnormal chloroplast development, and by the enhanced conversion of Chl b to Chl a. Moreover, the results indicated the same Chl-cycle pattern in the wild-type and C1 rice, indicating another Chl b degradation pathway. Furthermore, the results demonstrated that normal grana stacking, along with the absence of Chl b and greatly reduced levels of Chl a in C1, provide evidence to support the conclusion that other factors along with LHCII proteins are involved in grana stacking. The findings of this study provide insight into the molecular mechanisms that underlie different Chl a/b ratios in rice.Keywords: Chl-deficient mutant, grana stacked, photosynthesis, RNA-Seq, transcriptomic analysis
Procedia PDF Downloads 12419851 Aquatic Therapy Improving Balance Function of Individuals with Stroke: A Systematic Review with Meta-Analysis
Authors: Wei-Po Wu, Wen-Yu Liu, Wei−Ting Lin, Hen-Yu Lien
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Introduction: Improving balance function for individuals after stroke is a crucial target in physiotherapy. Aquatic therapy which challenges individual’s postural control in an unstable fluid environment may be beneficial in enhancing balance functions. The purposes of the systematic review with meta-analyses were to validate the effects of aquatic therapy in improving balance functions for individuals with strokes in contrast to conventional physiotherapy. Method: Available studies were explored from three electronic databases: PubMed, Scopus, and Web of Science. During literature search, the published date of studies was not limited. The study design of the included studies should be randomized controlled trials (RCTs) and the studies should contain at least one outcome measurement of balance function. The PEDro scale was adopted to assess the quality of included studies, while the 'Oxford Centre for Evidence-Based Medicine 2011 Levels of Evidence' was used to evaluate the level of evidence. After the data extraction, studies with same outcome measures were pooled together for meta-analysis. Result: Ten studies with 282 participants were included in analyses. The research qualities of the studies were ranged from fair to good (4 to 8 points). Levels of evidence of the included studies were graded as level 2 and 3. Finally, scores of Berg Balance Scale (BBS), Eye closed force plate center of pressure velocity (anterior-posterior, medial-lateral axis) and Timed up and Go test were pooled and analyzed separately. The pooled results shown improvement in balance function (BBS mean difference (MD): 1.39 points; 95% confidence interval (CI): 0.05-2.29; p=0.002) (Eye closed force plate center of pressure velocity (anterior-posterior axis) MD: 1.39 mm/s; 95% confidence interval (CI): 0.93-1.86; p<0.001) (Eye closed force plate center of pressure velocity (medial-lateral) MD: 1.48 mm/s; 95% confidence interval (CI): 0.15-2.82; p=0.03) and mobility (MD: 0.9 seconds; 95% CI: 0.07-1.73; p=0.03) of stroke individuals after aquatic therapy compared to conventional therapy. Although there were significant differences between two treatment groups, the differences in improvement were relatively small. Conclusion: The aquatic therapy improved general balance function and mobility in the individuals with stroke better than conventional physiotherapy.Keywords: aquatic therapy, balance function, meta-analysis, stroke, systematic review
Procedia PDF Downloads 20119850 Agro Morphological Characterization of Vicia faba L. Accessions in the Kingdom of Saudi Arabia
Authors: Zia Amjad, Salem Safar Alghamdi
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This experiment was carried out at student educational farm College of Food and Agriculture, KSU, kingdom of Saudi Arabia; in order to characterize 154 Vicia faba, characterization, PCA, ago-morphological diversity. Icia faba L. accessions were based on ipove and ibpgr descriptors. 24 agro-morphological characters including 11 quantitative and 13 qualitative were observed for genetic variation. All the results were analyzed using multivariate analysis i.e. principle component analysis. First 6 principle components with eigenvalue greater than one; accounted for 72% of available Vicia faba genetic diversity. However, first three components revealed more than 10% of genetic diversity each i.e. 22.36%, 15.86%, and 10.89% respectively. PCA distributed the V. faba accessions into different groups based on their performance for the characters under observation. PC-1 which represented 22.36% of the genetic diversity was positively associated with stipule spot pigmentation, intensity of streaks, pod degree of curvature and to some extent with 100 seed weight. PC-2 covered 15.86 of the genetic diversity and showed positive association for average seed weight per plant, pod length, number of seeds per plant, 100 seed weight, stipule spot pigmentation, intensity of streaks (same as in PC-1), and to some extent for pod degree of curvature and number of pods per plant. PC-3 revealed 10.89% of genetic diversity and expressed positive association for number of pods per plant and number of leaflets per plant.Keywords: Vicia faba, characterization, PCA, ago-morphological diversity
Procedia PDF Downloads 45819849 Risk Factors for High Resistance of Ciprofloxacin Against Escherichia coli in Complicated Urinary Tract Infection
Authors: Liaqat Ali, Khalid Farooq, Shafieullah Khan, Nasir Orakzai, Qudratullah
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Objectives: To determine the risk factors for high resistance of ciprofloxacin in complicated urinary tract infections. Materials and Methods: It is an analytical study that was conducted in the department of Urology (Team ‘C’) at Institute of Kidney Diseases Hayatabad Peshawar from 1st June 2012 till 31st December 2012. Total numbers of 100 patients with complicated UTI was selected in the study. Multivariate analysis and linear regression were performed for the detection of risk factors. All the data was recorded on structured Proforma and was analyzed on SPSS version 17. Results: The mean age of the patient was 55.6 years (Range 3-82 years). 62 patients were male while 38 patients were female. 66 isolates of E-Coli were found sensitive to ciprofloxacin while 34 isolates were found Resistant for ciprofloxacin. Using multivariate analysis and linear regression, an increasing age above 50 (p=0.002) History of urinary catheterization especially for bladder outflow obstruction (p=0.001) and previous multiple use of ciprofloxacin (p=0.001) and poor brand of ciprofloxacin were found to be independent risk factors for high resistance of ciprofloxacin. Conclusion: UTI is common illness across the globe with increasing trend of antimicrobial resistance for ciprofloxacin against E Coli in complicated UTI. The risk factors for emerging resistance are increasing age, urinary catheterization and multiple use and poor brand of ciprofloxacin.Keywords: urinary tract infection, ciprofloxacin, urethral catheterization, antimicrobial resistance
Procedia PDF Downloads 35419848 Effect of Site Amplification on Seismic Safety Evaluation of Flyover Pier
Authors: Mohammad Raihan Mukhlis, M. Abdur Rahman Bhuiyan
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Bangladesh is a developing country in which a lot of multi-span simply/continuous supported flyovers are being constructed in its major cities. Being situated in a seismically active region, seismic safety evaluation of flyovers is essential for seismic risk reduction. Effects of site amplification on seismic safety evaluation of flyover piers are the main concern of this study. In this regard, failure mode, lateral strength and displacement ductility of piers of a typical multi-span simply supported flyover have been evaluated by Japan Road Association (JRA) recommended guidelines, with and without considering site amplification. Ultimate flexural strengths of piers have been computed using the pushover analysis results. Shear capacity of piers has been calculated using the guidelines of JRA. Lateral strengths have been determined depending on the failure modes of the piers. Displacement ductility of piers has been computed using yield and ultimate displacements of the piers obtained from the pushover analysis results. Selected earthquake time history is used in seismic safety evaluation of the flyover piers. Finally, the ductility design method is used to conduct the seismic safety evaluation of the piers with and without considering site amplification. From the numerical results, it has been revealed that the effects of site amplification on seismic safety evaluation of bridge structures should be carefully taken into account.Keywords: displacement ductility, flyover pier, lateral strength, safety evaluation, site amplification
Procedia PDF Downloads 17019847 Comparing Forecasting Performances of the Bass Diffusion Model and Time Series Methods for Sales of Electric Vehicles
Authors: Andreas Gohs, Reinhold Kosfeld
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This study should be of interest for practitioners who want to predict precisely the sales numbers of vehicles equipped with an innovative propulsion technology as well as for researchers interested in applied (regional) time series analysis. The study is based on the numbers of new registrations of pure electric and hybrid cars. Methods of time series analysis like ARIMA are compared with the Bass Diffusion-model concerning their forecasting performances for new registrations in Germany at the national and federal state levels. Especially it is investigated if the additional information content from regional data increases the forecasting accuracy for the national level by adding predictions for the federal states. Results of parameters of the Bass Diffusion Model estimated for Germany and its sixteen federal states are reported. While the focus of this research is on the German market, estimation results are also provided for selected European and other countries. Concerning Bass-parameters and forecasting performances, we get very different results for Germany's federal states and the member states of the European Union. This corresponds to differences across the EU-member states in the adoption process of this innovative technology. Concerning the German market, the adoption is rather proceeded in southern Germany and stays behind in Eastern Germany except for Berlin.Keywords: bass diffusion model, electric vehicles, forecasting performance, market diffusion
Procedia PDF Downloads 16619846 Risk Assessments of Longest Dry Spells Phenomenon in Northern Tunisia
Authors: Majid Mathlouthi, Fethi Lebdi
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Throughout the world, the extent and magnitude of droughts have economic, social and environmental consequences. Today climate change has become more and more felt; most likely they increase the frequency and duration of droughts. An analysis by event of dry event, from series of observations of the daily rainfall is carried out. A daily precipitation threshold value has been set. A catchment localized in Northern Tunisia where the average rainfall is about 600 mm has been studied. Rainfall events are defined as an uninterrupted series of rainfall days understanding at least a day having received a precipitation superior or equal to a fixed threshold. The dry events are constituted of a series of dry days framed by two successive rainfall events. A rainfall event is a vector of coordinates the duration, the rainfall depth per event and the duration of the dry event. The depth and duration are found to be correlated. So we use conditional probabilities to analyse the depth per event. The negative binomial distribution fits well the dry event. The duration of the rainfall event follows a geometric distribution. The length of the climatically cycle adjusts to the Incomplete Gamma. Results of this analysis was used to study of the effects of climate change on water resources and crops and to calibrate precipitation models with little rainfall records. In response to long droughts in the basin, the drought management system is based on three phases during each of the three phases; different measurements are applied and executed. The first is before drought, preparedness and early warning; the second is drought management, mitigation in the event of drought; and the last subsequent drought, when the drought is over.Keywords: dry spell, precipitation threshold, climate vulnerability, adaptation measures
Procedia PDF Downloads 8419845 Atypical Intoxication Due to Fluoxetine Abuse with Symptoms of Amnesia
Authors: Ayse Gul Bilen
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Selective serotonin reuptake inhibitors (SSRIs) are commonly prescribed antidepressants that are used clinically for the treatment of anxiety disorders, obsessive-compulsive disorder (OCD), panic disorders and eating disorders. The first SSRI, fluoxetine (sold under the brand names Prozac and Sarafem among others), had an adverse effect profile better than any other available antidepressant when it was introduced because of its selectivity for serotonin receptors. They have been considered almost free of side effects and have become widely prescribed, however questions about the safety and tolerability of SSRIs have emerged with their continued use. Most SSRI side effects are dose-related and can be attributed to serotonergic effects such as nausea. Continuous use might trigger adverse effects such as hyponatremia, tremor, nausea, weight gain, sleep disturbance and sexual dysfunction. Moderate toxicity can be safely observed in the hospital for 24 hours, and mild cases can be safely discharged (if asymptomatic) from the emergency department once cleared by Psychiatry in cases of intentional overdose and after 6 to 8 hours of observation. Although fluoxetine is relatively safe in terms of overdose, it might still be cardiotoxic and inhibit platelet secretion, aggregation, and plug formation. There have been reported clinical cases of seizures, cardiac conduction abnormalities, and even fatalities associated with fluoxetine ingestions. While the medical literature strongly suggests that most fluoxetine overdoses are benign, emergency physicians need to remain cognizant that intentional, high-dose fluoxetine ingestions may induce seizures and can even be fatal due to cardiac arrhythmia. Our case is a 35-year old female patient who was sent to ER with symptoms of confusion, amnesia and loss of orientation for time and location after being found wandering in the streets unconsciously by police forces that informed 112. Upon laboratory examination, no pathological symptom was found except sinus tachycardia in the EKG and high levels of aspartate transaminase (AST) and alanine transaminase (ALT). Diffusion MRI and computed tomography (CT) of the brain all looked normal. Upon physical and sexual examination, no signs of abuse or trauma were found. Test results for narcotics, stimulants and alcohol were negative as well. There was a presence of dysrhythmia which required admission to the intensive care unit (ICU). The patient gained back her conscience after 24 hours. It was discovered from her story afterward that she had been using fluoxetine due to post-traumatic stress disorder (PTSD) for 6 months and that she had attempted suicide after taking 3 boxes of fluoxetine due to the loss of a parent. She was then transferred to the psychiatric clinic. Our study aims to highlight the need to consider toxicologic drug use, in particular, the abuse of selective serotonin reuptake inhibitors (SSRIs), which have been widely prescribed due to presumed safety and tolerability, for diagnosis of patients applying to the emergency room (ER).Keywords: abuse, amnesia, fluoxetine, intoxication, SSRI
Procedia PDF Downloads 19819844 The Effect of Arbitrary Support Conditions on the Static Behavior of Curved Beams Using the Finite Element Method
Authors: Hossein Mottaghi T., Amir R. Masoodi
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This study presents a finite curved element for analyzing the static behavior of curved beams within the elastic range. The objective is to enhance accuracy while reducing the number of elements by incorporating first-order shear deformations of Timoshenko beams. Initially, finite element formulations are developed by considering polynomial initial functions for axial, shear, and rotational deformations for a three-node element. Subsequently, nodal interpolation functions for this element are derived, followed by the construction of the element stiffness matrix. To enable the utilization of the stiffness matrix in the static analysis of curved beams, the constructed matrix in the local coordinates of the element is transformed to the global coordinate system using the rotation matrix. A numerical benchmark example is investigated to assess the accuracy and effectiveness of this method. Moreover, the influence of spring stiffness on the rotation of the endpoint of a clamped beam is examined by substituting each support reaction of the beam with a spring. In the parametric study, the effect of the central angle of the beam on the rotation of the beam's endpoint in a cantilever beam under a concentrated load is examined. This research encompasses various mechanical, geometrical, and boundary configurations to evaluate the static characteristics of curved beams, thus providing valuable insights for their analysis and examination.Keywords: curved beam, finite element method, first-order shear deformation theory, elastic support
Procedia PDF Downloads 7019843 Serum 25-Hydroxyvitamin D Levels and Depression in Persons with Human Immunodeficiency Virus Infection: A Cross-Sectional and Prospective Study
Authors: Kalpana Poudel-Tandukar
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Background: Human Immunodeficiency Virus (HIV) infection has been frequently associated with vitamin D deficiency and depression. Vitamin D deficiency increases the risk of depression in people without HIV. We assessed the cross-sectional and prospective associations between serum concentrations of 25-hydroxyvitamin D (25[OH]D) and depression in a HIV-positive people. Methods: A survey was conducted among 316 HIV-positive people aged 20-60 years residing in Kathmandu, Nepal for a cross-sectional association at baseline, and among 184 participants without depressive symptoms at baseline who responded to both baseline (2010) and follow-up (2011) surveys for prospective association. The competitive protein-binding assay was used to measure 25(OH)D levels and the Beck Depression Inventory-Ia method was used to measure depression, with cut off score 20 or higher. Relationships were assessed using multiple logistic regression analysis with adjustment of potential confounders. Results: The proportion of participants with 25(OH)D level of <20ng/mL, 20-30ng/mL, and >30ng/mL were 83.2%, 15.5%, and 1.3%, respectively. Only four participants with 25(OH)D level of >30ng/mL were excluded in the further analysis. The mean 25(OH)D level in men and women were 15.0ng/mL and 14.4ng/mL, respectively. Twenty six percent of participants (men:23%; women:29%) were depressed. Participants with 25(OH)D level of < 20 ng/mL had a 1.4 fold higher odds of depression in a cross-sectional and 1.3 fold higher odds of depression after 18 months of baseline compared to those with 25(OH)D level of 20-30ng/mL (p=0.40 and p=0.78, respectively). Conclusion: Vitamin D may not have significant impact against depression among HIV-positive people with 25(OH)D level below normal ( > 30ng/mL).Keywords: depression, HIV, Nepal, vitamin D
Procedia PDF Downloads 33219842 Identification of Two Novel Carbapenemase Gene Variants from a Carbapenem-Resistant Aeromonas Veronii Environmental Isolate
Authors: Rafael Estrada, Cristian Ruiz Rueda
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Carbapenems are last-resort antibiotics used in clinical settings to treat antibiotic-resistant bacterial infections. Thus, the emergence and spread of resistance to carbapenems is a major public health concern. Here, we have studied a carbapenem-resistant Aeromonas veronii strain previously isolated from a water sample from Sam Simeon Creek (Hearst San Simeon State Park, CA). Analysis of this isolate using disk-diffusion, CarbaNP, eCIM and mCIM assays revealed that it was resistant to amoxicillin-clavulanic acid and all carbapenems tested and that this isolate produced a potentially novel carbapenemase of the Metallo-β-lactamase family. Whole genome sequencing analysis revealed that this A. veronii isolate carries a novel variant of the blacₚₕₐ class β-carbapenemase gene that was closely related to the blacₚₕₐ₇ gene of Aeromonas jandaei. This isolate also carried a novel variant of the blaₒₓₐ class D carbapenemase gene that was most closely related to the blaₒₓₐ-₉₁₂ gene found in other Aeromonas veronii isolates. Finally, we also identified a novel class C β-lactamase gene moderately related to the blaFₒₓ-₁₇ gene of Providencia stuartii and other blaFₒₓ variants identified in Klebsiella pneumoniae, Escherichia coli and other Enterobacteriaceae. Overall, our findings reveal that environmental isolates are an important reservoir of multiple carbapenemases and other β-lactamases of clinical significance.Keywords: β-lactamases, carbapenem, antibiotic-resistant, aeromonas veronii
Procedia PDF Downloads 9219841 Dynamic Risk Identification Using Fuzzy Failure Mode Effect Analysis in Fabric Process Industries: A Research Article as Management Perspective
Authors: A. Sivakumar, S. S. Darun Prakash, P. Navaneethakrishnan
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In and around Erode District, it is estimated that more than 1250 chemical and allied textile processing fabric industries are affected, partially closed and shut off for various reasons such as poor management, poor supplier performance, lack of planning for productivity, fluctuation of output, poor investment, waste analysis, labor problems, capital/labor ratio, accumulation of stocks, poor maintenance of resources, deficiencies in the quality of fabric, low capacity utilization, age of plant and equipment, high investment and input but low throughput, poor research and development, lack of energy, workers’ fear of loss of jobs, work force mix and work ethic. The main objective of this work is to analyze the existing conditions in textile fabric sector, validate the break even of Total Productivity (TP), analyze, design and implement fuzzy sets and mathematical programming for improvement of productivity and quality dimensions in the fabric processing industry. It needs to be compatible with the reality of textile and fabric processing industries. The highly risk events from productivity and quality dimension were found by fuzzy systems and results are wrapped up among the textile fabric processing industry.Keywords: break even point, fuzzy crisp data, fuzzy sets, productivity, productivity cycle, total productive maintenance
Procedia PDF Downloads 33819840 Identification of Common Indicators of Family Environment of Pupils of Alternative Schools
Authors: Yveta Pohnětalová, Veronika Nováková, Lucie Hrašová
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The paper presents the results of research in which we were looking for common characteristics of the family environment of students alternative and innovative education systems. Topicality comes from the fact that nowadays in the Czech Republic there are several civic and parental initiatives held with the aim to establish schools for their children. The goal of our research was to reveal key aspects of these families and to identify their common indicators. Among other things, we were interested what reasons lead parents to decide to enroll their child into different education than standard (common). The survey was qualitative and there were eighteen respondents of parents of alternative schools´ pupils. The reason to implement qualitative design was the opportunity to gain deeper insight into the essence of phenomena and to obtain detailed information, which would become the basis for subsequent quantitative research. There have been semi structured interviews done with the respondents which had been recorded and transcribed. By an analysis of gained data (categorization and by coding), we found out that common indicator of our respondents is higher education and higher economic level. This issue should be at the forefront of the researches because there is lack of analysis which would provide a comparison of common and alternative schools in the Czech Republic especially with regard to quality of education. Based on results, we consider questions whether approaches of these parents towards standard education come from their own experience or from the lack of knowledge of current goals and objectives of education policy of the Czech Republic.Keywords: alternative schools, family environment, quality of education, parents´ approach
Procedia PDF Downloads 35219839 Modeling and Behavior of Structural Walls
Authors: Salima Djehaichia, Rachid Lassoued
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Reinforced concrete structural walls are very efficient elements for protecting buildings against excessive early damage and against collapse under earthquake actions. It is therefore of interest to develop a numerical model which simulates the typical behavior of these units, this paper presents and describes different modeling techniques that have been used by researchers and their advantages and limitations mentioned. The earthquake of Boumerdes in 2003 has demonstrated the fragility of structures and total neglect of sismique design rules in the realization of old buildings. Significant damage and destruction of buildings caused by this earthquake are not due to the choice of type of material, but the design and the study does not congruent with seismic code requirements and bad quality of materials. For idealizing the failure of rules, a parametric study focuses on: low rate of reinforcements, type of reinforcement, resistance moderate of concrete. As an application the modeling strategy based on finite elements combined with a discretization of wall more solicited by successive thin layers. The estimated performance level achieved during a seismic action is obtained from capacity curves under incrementally increasing loads. Using a pushover analysis, a characteristic non linear force-displacement relationship can be determined. The results of numeric model are confronted with those of Algerian Para seismic Rules (RPA) in force have allowed the determination of profits in terms of displacement, shearing action, ductility.Keywords: modeling, old building, pushover analysis, structural walls
Procedia PDF Downloads 24619838 Exploring the Correlation between Students' Performance in Educational Statistics and Research Methods in Education: The Influence of Undergraduate Programs
Authors: Justice Dadzie, Stacy H. Surman, Ruth K. Annan-Brew, Ifesinachi J. Ezugwu, Evans Addison
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This study aimed to explore the correlation between students' performance in educational statistics and research methods in education, as well as investigate potential differences in performance based on their undergraduate programs. A cross-sectional design was employed, and data was collected from 170 students enrolled in master of philosophy programs in the department of education and psychology. The correlation analysis revealed a strong positive correlation between students' performance in intermediate statistics in education and research methods in education. This indicates a close relationship between the two domains. The MANOVA analysis showed no significant differences in the linear combination of intermediate statistics in education and research methods in education scores across the different undergraduate programs. The tests of between-subjects effects further confirmed that the student's performance in intermediate statistics in education and research methods in education did not differ significantly across the different undergraduate programs. These findings contribute to the existing literature by providing insights into the correlation between educational statistics and research methods, and the influence of undergraduate program backgrounds on students' performance in these domains. The strong positive correlation between intermediate statistics and research methods highlights the importance of a solid foundation in statistics for understanding and applying research methods. Moreover, the consistent relationship across different academic backgrounds emphasizes the need for targeted interventions and support systems to enhance graduate students' competencies in these critical areas.Keywords: educational statistics, research methods, undergraduate programs, students performance
Procedia PDF Downloads 4419837 Analysis of a Discrete-time Geo/G/1 Queue Integrated with (s, Q) Inventory Policy at a Service Facility
Authors: Akash Verma, Sujit Kumar Samanta
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This study examines a discrete-time Geo/G/1 queueing-inventory system attached with (s, Q) inventory policy. Assume that the customers follow the Bernoulli process on arrival. Each customer demands a single item with arbitrarily distributed service time. The inventory is replenished by an outside supplier, and the lead time for the replenishment is determined by a geometric distribution. There is a single server and infinite waiting space in this facility. Demands must wait in the specified waiting area during a stock-out period. The customers are served on a first-come-first-served basis. With the help of the embedded Markov chain technique, we determine the joint probability distributions of the number of customers in the system and the number of items in stock at the post-departure epoch using the Matrix Analytic approach. We relate the system length distribution at post-departure and outside observer's epochs to determine the joint probability distribution at the outside observer's epoch. We use probability distributions at random epochs to determine the waiting time distribution. We obtain the performance measures to construct the cost function. The optimum values of the order quantity and reordering point are found numerically for the variety of model parameters.Keywords: discrete-time queueing inventory model, matrix analytic method, waiting-time analysis, cost optimization
Procedia PDF Downloads 4219836 Cleaner Production Options for Fishery Wastes around Lake Tana-Ethiopia
Authors: Demisash, Abate Getnet, Gudisa, Ababo Geleta, Daba, Berhane Olani
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As consumption trends of fish are rising in Ethiopia, assessment of the environmental performance of Fisheries becomes vital. Hence, Cleaner Production Assessment was conducted on Lake Tana No.1 Fish Supply Association. This paper focuses on determining the characteristics, quantity, and setting up cleaner production options for the site with the experimental investigation. The survey analysis showed that illegal waste dumping in Lake Tana is common practice in the area, and some of the main reasons raised were they have no option than doing this for dis-charging fish wastes. Quantifying a fish waste by examination of records at the point of generation resulted in a generation rate of 72,822.61 kg per year, which is a significant amount of waste and needs management system. The result of the proximate analysis showed high free fat content of about 12.33%, and this was a good candidate for the production of biodiesel that has been set as an option for fish waste utilization. Among the different waste management options, waste reduction by product optimization, which involves biodiesel production, was chosen as a potential method. Laboratory scale experiments were performed to produce a renewable energy source from the wastes. The resulting biodiesel was characterized and found to have a density of 0.756kg/L, viscosity 0.24p, and 153°C flashpoints, which shows the product has values in compliance with the American Society for Testing and Materials (ASTM) standards.Keywords: biodiesel, cleaner production, renewable energy, waste management
Procedia PDF Downloads 15019835 The Influence of Production Hygiene Training on Farming Practices Employed by Rural Small-Scale Organic Farmers - South Africa
Authors: Mdluli Fezile, Schmidt Stefan, Thamaga-Chitja Joyce
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In view of the frequently reported foodborne disease outbreaks caused by contaminated fresh produce, consumers have a preference for foods that meet requisite hygiene standards to reduce the risk of foodborne illnesses. Producing good quality fresh produce then becomes critical in improving market access and food security, especially for small-scale farmers. Questions of hygiene and subsequent microbiological quality in the rural small-scale farming sector of South Africa are even more crucial, given the policy drive to develop small-scale farming as a measure for reinforcement of household food security and reduction of poverty. Farming practices and methods, throughout the fresh produce value chain, influence the quality of the final product, which in turn determines its success in the market. This study’s aim was to therefore determine the extent to which training on organic farming methods, including modules such as Importance of Production Hygiene, influenced the hygienic farming practices employed by eTholeni small-scale organic farmers in uMbumbulu, KwaZulu-Natal- South Africa. Questionnaires were administered to 73 uncertified organic farmers and analysis showed that a total of 33 farmers were trained and supplied the local Agri-Hub while 40 had not received training. The questionnaire probed respondents’ attitudes, knowledge of hygiene and composting practices. Data analysis included descriptive statistics such as the Chi-square test and a logistic regression model. Descriptive analysis indicated that a majority of the farmers (60%) were female, most of which (73%) were above the age of 40. The logistic regression indicated that factors such as farmer training and prior experience in the farming sector had a significant influence on hygiene practices both at 5% significance levels. These results emphasize the importance of training, education and farming experience in implementing good hygiene practices in small-scale farming. It is therefore recommended that South African policies should advocate for small-scale farmer training, not only for subsistence purposes, but also with an aim of supplying produce markets with high fresh produce.Keywords: small-scale farmers, leafy salad vegetables, organic produce, food safety, hygienic practices, food security
Procedia PDF Downloads 42519834 A Study on the Failure Modes of Steel Moment Frame in Post-Earthquake Fire Using Coupled Mechanical-Thermal Analysis
Authors: Ehsan Asgari, Meisam Afazeli, Nezhla Attarchian
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Post-earthquake fire is considered as a major threat in seismic areas. After an earthquake, fire is possible in structures. In this research, the effect of post-earthquake fire on steel moment frames with and without fireproofing coating is investigated. For this purpose, finite element method is employed. For the verification of finite element results, the results of an experimental study carried out by previous researchers are used, and the predicted FE results are compared with the test results, and good agreement is observed. After ensuring the accuracy of the predictions of finite element models, the effect of post-earthquake fire on the frames is investigated taking into account the parameters including the presence or absence of fire protection, frame design assumptions, earthquake type and different fire scenario. Ordinary fire and post-earthquake fire effect on the frames is also studied. The plastic hinges induced by earthquake in the structure are determined in the beam to the column connection and in panel zone. These areas should be accurately considered when providing fireproofing coatings. The results of the study show that the occurrence of fire beside corner columns is the most damaging scenario that results in progressive collapse of structure. It was also concluded that the behavior of structure in fire after a strong ground motion is significantly different from that in a normal fire.Keywords: post earthquake fire, moment frame, finite element simulation, coupled temperature-displacement analysis, fire scenario
Procedia PDF Downloads 154