Search results for: determinants of travel mode choice
1097 Phytoremediation of Lead Polluted Soils with Native Weeds in Nigeria
Authors: Comfort Adeoye, Anthony Eneji
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Lead pollution by mining, industrial dumping, and other anthropogenic uses are corroding the environment. Efforts being made to control it include physical, chemical and biological methods. The failure of the aforementioned methods are largely due to the fact that they are cumbersome, expensive, and not eco-friendly. Some plant species can be used for remediation of these pollutants. The objective of this work is to investigate the abilities of two native weed species to remediate two lead-polluted soils: a) Battery dumpsite and, (b) Naturally occurring lead mine. Soil samples were taken from the two sites: a) Kumapayi in Ibadan, a battery dumpsite, (b) Zamfara, a natural lead mine. Screen house experiment in Complete Randomized Design (CRD) replicated three times was carried out at I.I.T.A. Unpolluted soils were collected and polluted with various rates of lead concentrations of 0, 0.1, 0.2, and 0.5%. These were planted with weed species. Plant growth parameters were monitored for twelve weeks, after which the plants were harvested. Dry weight and plant uptake of the lead were taken. Analysis of data was carried out using, Genstat, Excel and descriptive statistics. Relative concentration of lead (Pb) in the above and below ground parts of Gomphrena celusoides revealed that a higher amount of Pb is taken up in the root compared with the shoots at different levels of Pb pollution. However, lead uptake at 0.5% > 0.2% > 0.1% > Control. In essence, phytoremediation of Gomphrena is highest at soil pollution of 0.5% and its retention is greater in the root than the shoot.In S. pyramidalis, soil retention ranges from 0.1% > 0.5% > 0.2% > control. Uptake is highest at 0.5% > 0.1% > 0.2 in stem. Uptake in leaves is highest at 0.2%, but none in the 0.5% pollution. Therefore, different plant species exhibited different accumulative mode probably due to their physiological and rooting systems. Gomphrena spp. rooting system is tap root,while that of S.pyramidalis is fibrous.Keywords: grass, lead, phytoremediation, pollution
Procedia PDF Downloads 3251096 Numerical Solution of Portfolio Selecting Semi-Infinite Problem
Authors: Alina Fedossova, Jose Jorge Sierra Molina
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SIP problems are part of non-classical optimization. There are problems in which the number of variables is finite, and the number of constraints is infinite. These are semi-infinite programming problems. Most algorithms for semi-infinite programming problems reduce the semi-infinite problem to a finite one and solve it by classical methods of linear or nonlinear programming. Typically, any of the constraints or the objective function is nonlinear, so the problem often involves nonlinear programming. An investment portfolio is a set of instruments used to reach the specific purposes of investors. The risk of the entire portfolio may be less than the risks of individual investment of portfolio. For example, we could make an investment of M euros in N shares for a specified period. Let yi> 0, the return on money invested in stock i for each dollar since the end of the period (i = 1, ..., N). The logical goal here is to determine the amount xi to be invested in stock i, i = 1, ..., N, such that we maximize the period at the end of ytx value, where x = (x1, ..., xn) and y = (y1, ..., yn). For us the optimal portfolio means the best portfolio in the ratio "risk-return" to the investor portfolio that meets your goals and risk ways. Therefore, investment goals and risk appetite are the factors that influence the choice of appropriate portfolio of assets. The investment returns are uncertain. Thus we have a semi-infinite programming problem. We solve a semi-infinite optimization problem of portfolio selection using the outer approximations methods. This approach can be considered as a developed Eaves-Zangwill method applying the multi-start technique in all of the iterations for the search of relevant constraints' parameters. The stochastic outer approximations method, successfully applied previously for robotics problems, Chebyshev approximation problems, air pollution and others, is based on the optimal criteria of quasi-optimal functions. As a result we obtain mathematical model and the optimal investment portfolio when yields are not clear from the beginning. Finally, we apply this algorithm to a specific case of a Colombian bank.Keywords: outer approximation methods, portfolio problem, semi-infinite programming, numerial solution
Procedia PDF Downloads 3091095 Library Screening and Evaluation of Mycobacterium tuberculosis Ketol-Acid Reductoisomerase Inhibitors
Authors: Vagolu S. Krishna, Shan Zheng, Estharla M. Rekha, Luke W. Guddat, Dharmarajan Sriram
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Tuberculosis (TB) remains a major threat to human health. This due to the fact that current drug treatments are less than optimal as well as the rising occurrence of multi drug-resistant and extensively drug-resistant strains of the etiological agent, Mycobacterium tuberculosis (Mt). Given the wide-spread significance of this disease, we have undertaken a design and evaluation program to discover new anti-TB drug leads. Here, our attention is focused on ketol-acid reductoisomerase (KARI), the second enzyme in the branched-chain amino acid biosynthesis pathway. Importantly, this enzyme is present in bacteria but not in humans, making it an attractive proposition for drug discovery. In the present work, we used high-throughput virtual screening to identify seventeen potential inhibitors of KARI using the Birla Institute of Technology and Science in-house database. Compounds were selected based on high docking scores, which were assigned as the result of favourable interactions between the compound and the active site of KARI. The Ki values for two leads, compounds 14 and 16 are 3.71 and 3.06 µM, respectively for Mt KARI. To assess the mode of binding, 100 ns molecular dynamics simulations for these two compounds in association with Mt KARI were performed and showed that the complex was stable with an average RMSD of less than 2.5 Å for all atoms. Compound 16 showed an MIC of 2.06 ± 0.91 µM and a 1.9 fold logarithmic reduction in the growth of Mt in an infected macrophage model. The two compounds exhibited low toxicity against murine macrophage RAW 264.7 cell lines. Thus, both compounds are promising candidates for development as an anti-TB drug leads.Keywords: ketol-acid reductoisomerase, macrophage, molecular docking and dynamics, tuberculosis
Procedia PDF Downloads 1221094 Structural Anatomy and Deformation Pattern of the Palghat-Cauvery Shear Zone in the Central Sector, Tamil Nadu, Southern India
Authors: Mrinal Mukherjee, Gargi Seal, Bitopan Mazumdar, Prakhar Agarwal
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The central sector of Palghat-Cauvery Shear zone Tamil Nadu, India, had been studied with reference to development, mode of occurrence, interrelationship and variation of structural elements. The litho assemblages of the study area include gneisses migmatites granites and bear signature of multistage deformation patterns. The early deformation D1 is characterized in migmatites and gneisses by the development of tight to isoclinal, recumbent to reclined folds within the compositional bands that are refolded subsequently to produce D2 deformation structures ranging from type-II to type-III superposed geometry. The granite, in general, is undeformed, save a few places where strong mylonitic foliation developed with stretching lineation on it. The D1-D2 structures of gneisses and migmatites were affected by a D3 stage- E-W trending shear zone (Palghat-Cauvery Shear zone) that dips steeply towards north. The shear zone is characterized by the development of mylonite zone with stretching lineation on foliation, shear band structures, modification of geometry and orientation of earlier folds and foliations within the shear zone and development of shear induced folds and foliations. Several anastomosing lenses of shear zones define the larger Palghat-Cauvery Shear zone. The orientation of the shear induced folds and foliations and deflections of earlier foliation and folds within the Palghat-Cauvery shear zone indicate an oblique-slip thrust-shear with north-towards-east sense of displacement. The E-W trending shear zone is further openly folded along N-S in the D4 stage of deformation.Keywords: deformation, migmatites, mylonites, shear zones
Procedia PDF Downloads 1901093 Statistical Approach to Identify Stress and Biases Impairing Decision-Making in High-Risk Industry
Authors: Ph. Fauquet-Alekhine
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Decision-making occurs several times an hour when working in high risk industry and an erroneous choice might have undesirable outcomes for people and the environment surrounding the industrial plant. Industrial decisions are very often made in a context of acute stress. Time pressure is a crucial stressor leading decision makers sometimes to boost up the decision-making process and if it is not possible then shift to the simplest strategy. We thus found it interesting to update the characterization of the stress factors impairing decision-making at Chinon Nuclear Power Plant (France) in order to optimize decision making contexts and/or associated processes. The investigation was based on the analysis of reports addressing safety events over the last 3 years. Among 93 reports, those explicitly addressing decision-making issues were identified. Characterization of each event was undertaken in terms of three criteria: stressors, biases impairing decision making and weaknesses of the decision-making process. The statistical analysis showed that biases were distributed over 10 possibilities among which the hypothesis confirmation bias was clearly salient. No significant correlation was found between criteria. The analysis indicated that the main stressor was time pressure and highlights an unexpected form of stressor: the trust asymmetry principle of the expert. The analysis led to the conclusion that this stressor impaired decision-making from a psychological angle rather than from a physiological angle: it induces defensive bias of self-esteem, self-protection associated with a bias of confirmation. This leads to the hypothesis that this stressor can intervene in some cases without being detected, and to the hypothesis that other stressors of the same kind might occur without being detected too. Further investigations addressing these hypotheses are considered. The analysis also led to the conclusion that dealing with these issues implied i) decision-making methods being well known to the workers and automated and ii) the decision-making tools being well known and strictly applied. Training was thus adjusted.Keywords: bias, expert, high risk industry, stress.
Procedia PDF Downloads 1121092 The Enlightenment Project in the Arab World: Saudi Arabia as a Case Study in Modern Islamic Thought
Authors: Khawla Almulla
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It is noticed that many Arab intellectuals have called to the need and the importance of enlightenment and its application in their communities, such as Saudi Arabia. To every Islamic state, the Kingdom of Saudi Arabia represents a strategic cornerstone, since it is considered the cradle of Islam. It is the Land of the Two Holy Mosques: the Holy Mosque in Makkah surrounding the Kaaba, towards which all Muslims around the world turn while performing daily prayers and even travel to if possible in order to perform the Hajj (Pilgrimage). It also has the Prophet'ـ‘s Holy Mosque in Al-Madinah Al-Munawarah, which contains the tomb of Prophet Muhammad (pbuh). Therefore, Saudi Arabia occupies an eminent position among Arab and Islamic countries on a religious level. Saudi Arabia has become the most influential country in the Arab world, since it has one-third of the oil resources outside Central Asia, China and Russia .It is the world’s largest producer and exporter of oil. Discovering oil in Saudi Arabia converted it from an important country for Muslims-only to an important country for the major industrial countries and also the developing countries, as well. For various reasons, the diversity of intellectual currents can play a significant role in each community by way of cultural improvement, the development of civilization and the education of people until they become accustomed to accepting or rejecting opinions or ideas which differ from or oppose their own. In addition, the intellectual pluralism and cultural diversity can play a variety of roles. This helps promote dialogue and understanding between different groups or schools of thought. It can also develop cognitive skills, by exchanging ideas and views between different schools and intellectual currents. However, in Saudi Arabia there is much to oppose this plurality. The situation today shows that having a variety of ideologies and differences of cultures are not considered a reasonable way to develop intellectually as an individual or as a country. Rather the opposite is recommended, such that the ideologies of different groups are enough to bring out intellectual conflict and then to the segregation of society. As a consequence, extremism of thought from the different currents in Saudi Arabia has become apparent. This research is of great importance in its exploration of two significant themes. First, it highlights the Saudi Arabian background, in particular the historical, religious and social contexts, in order to understand the background of each religious or liberal movement and find the core of the intellectual differences between them. In addition, the aim of this research is to show the importance of moderation in Islamic thought in Saudi Arabia by tracing the thoughts and views of Dr Salman Al-Odah, whom he has considered to be the most important moderate thinker in Saudi Arabia.Keywords: Saudi Arabia, intellectual movements, religious movements, extremism, moderation, Salafism, liberalism, Salman Al-Odah
Procedia PDF Downloads 2901091 On Crack Tip Stress Field in Pseudo-Elastic Shape Memory Alloys
Authors: Gulcan Ozerim, Gunay Anlas
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In shape memory alloys, upon loading, stress increases around crack tip and a martensitic phase transformation occurs in early stages. In many studies the stress distribution in the vicinity of the crack tip is represented by using linear elastic fracture mechanics (LEFM) although the pseudo-elastic behavior results in a nonlinear stress-strain relation. In this study, the HRR singularity (Hutchinson, Rice and Rosengren), that uses Rice’s path independent J-integral, is tried to formulate the stress distribution around the crack tip. In HRR approach, the Ramberg-Osgood model for the stress-strain relation of power-law hardening materials is used to represent the elastic-plastic behavior. Although it is recoverable, the inelastic portion of the deformation in martensitic transformation (up to the end of transformation) resembles to that of plastic deformation. To determine the constants of the Ramberg-Osgood equation, the material’s response is simulated in ABAQUS using a UMAT based on ZM (Zaki-Moumni) thermo-mechanically coupled model, and the stress-strain curve of the material is plotted. An edge cracked shape memory alloy (Nitinol) plate is loaded quasi-statically under mode I and modeled using ABAQUS; the opening stress values ahead of the cracked tip are calculated. The stresses are also evaluated using the asymptotic equations of both LEFM and HRR. The results show that in the transformation zone around the crack tip, the stress values are much better represented when the HRR singularity is used although the J-integral does not show path independent behavior. For the nodes very close to the crack tip, the HRR singularity is not valid due to the non-proportional loading effect and high-stress values that go beyond the transformation finish stress.Keywords: crack, HRR singularity, shape memory alloys, stress distribution
Procedia PDF Downloads 3251090 The Hydrotrope-Mediated, Low-Temperature, Aqueous Dissolution of Maize Starch
Authors: Jeroen Vinkx, Jan A. Delcour, Bart Goderis
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Complete aqueous dissolution of starch is notoriously difficult. A high-temperature autoclaving process is necessary, followed by cooling the solution below its boiling point. The cooled solution is inherently unstable over time. Gelation and retrogradation processes, along with aggregation-induced by undissolved starch remnants, result in starch precipitation. We recently observed the spontaneous gelatinization of native maize starch (MS) in aqueous sodium salicylate (NaSal) solutions at room temperature. A hydrotropic mode of solubilization is hypothesized. Differential scanning calorimetry (DSC) and polarized optical microscopy (POM) of starch dispersions in NaSal solution were used to demonstrate the room temperature gelatinization of MS at different concentrations of MS and NaSal. The DSC gelatinization peak shifts to lower temperatures, and the gelatinization enthalpy decreases with increasing NaSal concentration. POM images confirm the same trend through the disappearance of the ‘Maltese cross’ interference pattern of starch granules. The minimal NaSal concentration to induce complete room temperature dissolution of MS was found to be around 15-20 wt%. The MS content of the dispersion has little influence on the amount of NaSal needed to dissolve it. The effect of the NaSal solution on the MS molecular weight was checked with HPSEC. It is speculated that, because of its amphiphilic character, NaSal enhances the solubility of MS in water by association with the more hydrophobic MS moieties, much like urea, which has also been used to enhance starch dissolution in alkaline aqueous media. As such small molecules do not tend to form micelles in water, they are called hydrotropes rather than surfactants. A minimal hydrotrope concentration (MHC) is necessary for the hydrotropes to structure themselves in water, resulting in a higher solubility of MS. This is the case for the system MS/NaSal/H₂O. Further investigations into the putative hydrotropic dissolution mechanism are necessary.Keywords: hydrotrope, dissolution, maize starch, sodium salicylate, gelatinization
Procedia PDF Downloads 1881089 Insights into Child Malnutrition Dynamics with the Lens of Women’s Empowerment in India
Authors: Bharti Singh, Shri K. Singh
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Child malnutrition is a multifaceted issue that transcends geographical boundaries. Malnutrition not only stunts physical growth but also leads to a spectrum of morbidities and child mortality. It is one of the leading causes of death (~50 %) among children under age five. Despite economic progress and advancements in healthcare, child malnutrition remains a formidable challenge for India. The objective is to investigate the impact of women's empowerment on child nutrition outcomes in India from 2006 to 2021. A composite index of women's empowerment was constructed using Confirmatory Factor Analysis (CFA), a rigorous technique that validates the measurement model by assessing how well-observed variables represent latent constructs. This approach ensures the reliability and validity of the empowerment index. Secondly, kernel density plots were utilised to visualise the distribution of key nutritional indicators, such as stunting, wasting, and overweight. These plots offer insights into the shape and spread of data distributions, aiding in understanding the prevalence and severity of malnutrition. Thirdly, linear polynomial graphs were employed to analyse how nutritional parameters evolved with the child's age. This technique enables the visualisation of trends and patterns over time, allowing for a deeper understanding of nutritional dynamics during different stages of childhood. Lastly, multilevel analysis was conducted to identify vulnerable levels, including State-level, PSU-level, and household-level factors impacting undernutrition. This approach accounts for hierarchical data structures and allows for the examination of factors at multiple levels, providing a comprehensive understanding of the determinants of child malnutrition. Overall, the utilisation of these statistical methodologies enhances the transparency and replicability of the study by providing clear and robust analytical frameworks for data analysis and interpretation. Our study reveals that NFHS-4 and NFHS-5 exhibit an equal density of severely stunted cases. NFHS-5 indicates a limited decline in wasting among children aged five, while the density of severely wasted children remains consistent across NFHS-3, 4, and 5. In 2019-21, women with higher empowerment had a lower risk of their children being undernourished (Regression coefficient= -0.10***; Confidence Interval [-0.18, -0.04]). Gender dynamics also play a significant role, with male children exhibiting a higher susceptibility to undernourishment. Multilevel analysis suggests household-level vulnerability (intra-class correlation=0.21), highlighting the need to address child undernutrition at the household level.Keywords: child nutrition, India, NFHS, women’s empowerment
Procedia PDF Downloads 331088 The Multiaxial Load Proportionality Effect on the Fracture Surface Topography of Forged Magnesium Alloys
Authors: Andrew Gryguć, Seyed Behzad Behravesh, Hamid Jahed, Mary Wells, Wojciech Macek, Bruce Williams
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This extended abstract investigates the influence of the multiaxial loading on the fatigue behavior of forged magnesium through quantitative analysis of its fracture surface topography and mesoscopic cracking orientation. Fatigue tests were performed on hollow tubular sample geometries extracted from closed-die forged AZ80 Mg components, with three different multiaxial strain paths (axial/shear), proportional, 45° out of phase, and 90° out of phase. Regardless of the strain path, fatigue cracks are initiated at the outer surface of the specimen where the combined stress state is largest. Depending on the salient mode of deformation, distinctive features in the fracture surface manifested themselves with different topographic amplitudes, surface roughness, and mesoscopic cracking orientation in the vicinity of the initiation site. The dominant crack propagation path was in the circumferential direction of the hollow tubular specimen (i.e., cracking transverse to the sample axis, with little to no branching), which is congruent with previous findings of low to moderate shear strain energy density (SED) multiaxial loading. For proportional loading, the initiation zone surface morphology was largely flat and striated, whereas, at phase angles of 45° and 90°, the initiation surface became more faceted and inclined. Overall, both a qualitative and quantitative link was developed between the fracture surface morphology and the level of non-proportionality in the loading providing useful insight into the fracture mechanics of forged magnesium as a relevant focus for future study.Keywords: fatigue, fracture, magnesium, forging, fractography, anisotropy, strain energy density, asymmetry, multiaxial fatigue
Procedia PDF Downloads 821087 Effects of Transit Fare Discount Programs on Passenger Volumes and Transferring Behaviors
Authors: Guan-Ying Chen, Han-Tsung Liou, Shou-Ren Hu
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To address traffic congestion problems and encourage the use of public transportation systems in the Taipei metropolitan area, the Taipei City Government and the New Taipei City Government implemented a monthly ticket policy on April 16, 2018. This policy offers unlimited rides on the Taipei MRT, Taipei City Bus, New Taipei City Bus, Danhai Light Rail, and Public Bike (YouBike) on a monthly basis. Additionally, both city governments replaced the smart card discount policy with a new frequent flyer discount program (referred to as the loyal customer program) on February 1, 2020, introducing a differential pricing policy. Specifically, the more frequently the Taipei MRT system is used, the greater the discounts users receive. To analyze the impact of the Taipei public transport monthly ticket policy and the frequent user discount program on the passenger volume of the Taipei MRT system and the transferring behaviors of MRT users, this study conducts a trip-chain analysis using transaction data from Taipei MRT smart cards between September 2017 and December 2020. To achieve these objectives, the study employs four indicators: 1) number of passengers, 2) average number of rides, 3) average trip distance, and 4) instances of multiple consecutive rides. The study applies the t-test and Mann-Kendall trend test to investigate whether the proposed indicators have changed over time due to the implementation of the discount policy. Furthermore, the study examines the travel behaviors of passengers who use monthly tickets. The empirical results of the study indicate that the implementation of the Taipei public transport monthly ticket policy has led to an increase in the average number of passengers and a reduction in the average trip distance. Moreover, there has been a significant increase in instances of multiple consecutive rides, attributable to the unlimited rides offered by the monthly tickets. The impact of the frequent user discount program on changes in MRT passengers is not as pronounced as that of the Taipei public transportation monthly ticket policy. This is partly due to the fact that the frequent user discount program is only applicable to the Taipei MRT system, and the passenger volume was greatly affected by the COVID-19 pandemic. The findings of this research can serve as a reference for Taipei MRT Corporation in formulating its fare strategy and can also provide guidance for the Taipei and New Taipei City Governments in evaluating differential pricing policies for public transportation systems.Keywords: frequent user discount program, mass rapid transit, monthly ticket, smart card
Procedia PDF Downloads 831086 Explore the Effect of Telecare for the Elderly in Preventing and Delaying the Quality of Disability Care with Bluetooth Brainwave Equipment
Authors: Jui-Chen Huang
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The purpose of this study is to explore the effects of telecare on preventing and delaying the quality of disability care in elderly people with portable comfort Bluetooth brainwave devices with remote healthcare functions. Through the teaching videos and remotely teaching the elderly, which had ever learned the care courses of the prevent and delay disability, these elderly did muscle strength training. Then this paper explores the effect of training with the data by SPSS 18.0 statistical software. The data is collected with pre-test, post-test and analyze data from the measure of the Bluetooth brain wave equipment including the pressure index, relaxation index, attention and fatigue index of the elderly. In this study, 30 elderly people who had taken preventive and delayed disability care courses were studied to explore the effect of their care quality improvement. The results showed that the pressure index, relaxation index, attention, and fatigue index of the elderly had statistically significant differences in two months. It can be seen that elderly people who have been treated to prevent and delay disability care courses can significantly improve their care quality if they continue to receive intensive training to prevent and delay disability through remote mode. This telecare is applied to the elderly program that has been used to prevent and delay disability care courses. It is worth continuing to promote, and it is recommended that follow-up studies be conducted in a longer-term manner to explore long-term benefits. It can solve the current insufficiency of long-term care resources, but the demand is urgent.Keywords: telecare, bluetooth brainwave equipment, prevention and delay of disability, the elderly, care quality
Procedia PDF Downloads 1491085 An Assessment of Inland Transport Operator's Competitiveness in Phnom Penh, Cambodia
Authors: Savin Phoeun
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Long time civil war, economic, infrastructure, social, and political structure were destroyed and everything starts from zero. Transport and communication are the key feature of the national economic growth, especially inland transport and other mode take a complementary role which supported by government and international organization both direct and indirect to private sector and small and medium size enterprises. The objectives of this study are to study the general characteristics, capacity and competitive KPIs of Cambodian Inland Transport Operators. Questionnaire and interview were formed from capacity and competitiveness key performance indicators to take apart in survey to Inland Transport Companies in Phnom Penh capital city of Cambodia. And descriptive statistics was applied to identify the data. The result of this study divided into three distinct sectors: 1). Management ability of transport operators – capital management, financial and qualification are in similar level which can compete between local competitors (moderated level). 2). Ability in operation: customer service providing is better but seemed in high cost operation because mostly they are in family size. 3). Local Cambodian Inland Transport Service Providers are able to compete with each other because they are in similar operation level while Thai competitors mostly higher than. The suggestion and recommendation from the result that inland transport companies should access to new technology, improve strategic management, build partnership (join/corporate) to be bigger size of capital and company in order to attract truthfulness from customers and customize the services to satisfy. Inland Service Providers should change characteristic from only cost competitive to cost saving and service enhancement.Keywords: assessment, competitiveness, inland transport, operator
Procedia PDF Downloads 2611084 Youth Empowerment: A Pathway to Unlocking Entrepreneurial Skills and Employability in Enugu State, Nigeria
Authors: Odenigbo Veronica Ngozi, Ukwuaba Loretta Chika, Ukamaka Eze
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This study delved into youth’s empowerment pathway to unlocking entrepreneurial skills and employability in Enugu state, Nigeria. The purpose of the study is to ascertain the effect of youth joblessness in Enugu State. Two research questions guided the study, and two null hypotheses, which were formulated and tested at a 0.05 level of significance, were used for the analysis. A descriptive survey research design was employed for the study. The population for the study consisted of 103 male and female youths in Enugu state, who were randomly sampled among youths as respondents. A structured questionnaire which was developed by researchers and titled ‘Youth Empowerment a Pathway to Unlocking Entrepreneurial Skills and Employability (YEPUESEQ)’, was used to elicit information from the respondents. The instrument was validated by three experts, one from the Department of Measurement and Evaluation and two from the Department of Continuing Education and Development Studies, all from Enugu State University of Science and Technology, Agbani (ESUT). Cronbach Alpha reliability estimate was used to determine the internal consistency of the instrument with a reliability index of 0.74, indicating that the instrument is highly reliable and suitable to elicit information from the respondent. Data collected were analyzed using mean and standard deviation to answer the two research questions, while the null hypotheses were tested at 0.05 level of significance using a t-test. The findings of the study indicated that when the youths are jobless, they tend to join bad gangs in as much as they can get money, but when they are empowered, they tend towards supporting themselves, the community, and the nation as a whole in bringing in human, economic and social development to society. Based on the findings, the researchers recommended, among others, that the government should establish skill acquisition centers while the youths can enroll for a particular skill of their choice with good facilities, infrastructures and qualified facilitators.Keywords: youth, empowerment, entrepreneurial skill, employability skill
Procedia PDF Downloads 261083 Exploring Tweeters’ Concerns and Opinions about FIFA Arab Cup 2021: An Investigation Study
Authors: Md. Rafiul Biswas, Uzair Shah, Mohammad Alkayal, Zubair Shah, Othman Althawadi, Kamila Swart
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Background: Social media platforms play a significant role in the mediated consumption of sport, especially so for sport mega-event. The characteristics of Twitter data (e.g., user mentions, retweets, likes, #hashtag) accumulate the users in one ground and spread information widely and quickly. Analysis of Twitter data can reflect the public attitudes, behavior, and sentiment toward a specific event on a larger scale than traditional surveys. Qatar is going to be the first Arab country to host the mega sports event FIFA World Cup 2022 (Q22). Qatar has hosted the FIFA Arab Cup 2021 (FAC21) to serve as a preparation for the mega-event. Objectives: This study investigates public sentiments and experiences about FAC21 and provides an insight to enhance the public experiences for the upcoming Q22. Method: FCA21-related tweets were downloaded using Twitter Academic research API between 01 October 2021 to 18 February 2022. Tweets were divided into three different periods: before T1 (01 Oct 2021 to 29 Nov 2021), during T2 (30 Nov 2021 -18 Dec 2021), and after the FAC21 T3 (19 Dec 2021-18 Feb 2022). The collected tweets were preprocessed in several steps to prepare for analysis; (1) removed duplicate and retweets, (2) removed emojis, punctuation, and stop words (3) normalized tweets using word lemmatization. Then, rule-based classification was applied to remove irrelevant tweets. Next, the twitter-XLM-roBERTa-base model from Huggingface was applied to identify the sentiment in the tweets. Further, state-of-the-art BertTopic modeling will be applied to identify trending topics over different periods. Results: We downloaded 8,669,875 Tweets posted by 2728220 unique users in different languages. Of those, 819,813 unique English tweets were selected in this study. After splitting into three periods, 541630, 138876, and 139307 were from T1, T2, and T3, respectively. Most of the sentiments were neutral, around 60% in different periods. However, the rate of negative sentiment (23%) was high compared to positive sentiment (18%). The analysis indicates negative concerns about FAC21. Therefore, we will apply BerTopic to identify public concerns. This study will permit the investigation of people’s expectations before FAC21 (e.g., stadium, transportation, accommodation, visa, tickets, travel, and other facilities) and ascertain whether these were met. Moreover, it will highlight public expectations and concerns. The findings of this study can assist the event organizers in enhancing implementation plans for Q22. Furthermore, this study can support policymakers with aligning strategies and plans to leverage outstanding outcomes.Keywords: FIFA Arab Cup, FIFA, Twitter, machine learning
Procedia PDF Downloads 1001082 Selective Recovery and Molecular Identification of Laccase-Producing Bacteria from Selected Terrestrial and Aquatic Milieu in the Eastern Cape, South Africa: Toward the Production of Environmentally Relevant Biocatalysts
Authors: John Onolame Unuofin, Uchechukuw U. Nwodo, Anthony I. Okoh
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Laccase is constantly gaining status as important biocatalyst in biotechnology. The illimitable potential of its industrial applications and the corresponding aggressive need for phenomenal volumes of extracellularly secreted laccases have called for its interminable production from sources which are able to meet this demand within a relatively short period of time, preferably bacteria. In response to this call, this study was designed to source for laccase-producing bacteria from different environmental matrices. Three sampling environments were chosen such as wastewater treatment plants, University of Fort Hare vicinity and the Hogback woodland, all within the Eastern Cape, South Africa. Samples such as effluents, sediments, leaf litters, degrading wood and rock scrapings were selectively enriched with some model aromatic compounds and were further screened qualitatively and quantitatively on five phenolic substrates ABTS (2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), Guaiacol, 1-Naphthol, Potassium Ferric Cyanide and Syringaldazine). Basis for selection was their ability to elicit a colour change on at least three of the above mentioned agar based assay substrates. The choice isolates were further identified based on 16S rRNA molecular identification techniques. 33 isolates were screened out of the 40 representative distinct colonies during the qualitative plate screens, while quantitative screens selected out 11 bacterial isolates. They were, based on molecular identification, desginated as members of the genera Pseudomonas, Stenotrophomonas and Citrobacter of the gammaproteobacteria and Bordetalla and Achromobacter of the betaproteobacteria respectively. We therefore conclude based on our outcomes that we may have isolated efficient laccase-producing bacteria, which might be of beneficial significance in catalysis and biotechnology.Keywords: beta proteobacteria, catalysis, gammaproteobacteria, laccase
Procedia PDF Downloads 1741081 A Novel Mediterranean Diet Index from the Middle East and North Africa Region: Comparison with Europe
Authors: Farah Naja, Nahla Hwalla, Leila Itani, Shirine Baalbaki, Abla Sibai, Lara Nasreddine
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Purpose: To propose an index for assessing adherence to a Middle-Eastern version of the Mediterranean diet as represented by the traditional Lebanese Mediterranean diet (LMD), to evaluate the association between the LMD and selected European Mediterranean diets (EMD); to examine socio-demographic and lifestyle correlates of adherence to Mediterranean diet (MD) among Lebanese adults. Methods: Using nationally representative dietary intake data of Lebanese adults, an index to measure adherence to the LMD was derived. The choice of food groups used for calculating the LMD score was based on results of previous factor analyses conducted on the same dataset. These food groups included fruits, vegetables, legumes, olive oil, burghol, dairy products, starchy vegetables, dried fruits, and eggs. Using Pearson’s correlation and scores tertiles distributions agreement, the derived LMD index was compared to previously published EMD indexes from Greece, Spain, Italy, France, and EPIC. Results: Fruits, vegetables and olive oil were common denominators to all MD scores. Food groups, specific to the LMD, included burghol and dried fruits. The LMD score significantly correlated with the EMD scores, while being closest to the Italian (r=0.57) and farthest from the French (r=0.21). Percent agreement between scores’ tertile distributions and Kappa statistics confirmed these findings. Multivariate linear regression showed that older age, higher educational, female gender, and healthy lifestyle characteristics were associated with increased adherence to all MD studied. Conclusion: A novel LMD index was proposed to characterize Mediterranean diet in Lebanon, complementing international efforts to characterize the MD and its association with disease risk.Keywords: mediterranean diet, adherence, Middle-East, Lebanon, Europe
Procedia PDF Downloads 4091080 Neo-liberalism and Theoretical Explanation of Poverty in Africa: The Nigerian Perspective
Authors: Omotoyosi Bilikies Ilori, Adekunle Saheed Ajisebiyawo
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After the Second World War, there was an emergence of a new stage of capitalist globalization with its Neo-liberal ideology. There were global economic and political restructurings that affected third-world countries like Nigeria. Neo-liberalism is the driving force of globalization, which is the latest manifestation of imperialism that engenders endemic poverty in Nigeria. Poverty is severe and widespread in Nigeria. Poverty entails a situation where a person lives on less than one dollar per day and has no access to basic necessities of life. Poverty is inhuman and a breach of human rights. The Nigerian government initiated some strategies in the past to help in poverty reduction. Neo-liberalism manifested in the Third World, such as Nigeria, through the privatization of public enterprises, trade liberalization, and the rollback of the state investments in providing important social services. These main ideas of Neo-liberalism produced poverty in Nigeria and also encouraged the abandonment of the social contract between the government and the people. There is thus a gap in the provision of social services and subsidies for the masses, all of which Neo-liberal ideological positions contradict. This paper is a qualitative study which draws data from secondary sources. The theoretical framework is anchored on the market theory of capitalist globalization and public choice theory. The objectives of this study are to (i) examine the impacts of Neo-liberalism on poverty in Nigeria as a typical example of a Third World country and (ii) find out the effects of Neo-liberalism on the provision of social services and subsidies and employment. The findings from this study revealed that (i) the adoption of the Neo-liberal ideology by the Nigerian government has led to increased poverty and poor provision of social services and employment in Nigeria; and (ii) there is an increase in foreign debts which compounds poverty situation in Nigeria. This study makes the following recommendations: (i) Government should adopt strategies that are pro-poor to eradicate poverty; (ii) The Trade Unions and the masses should develop strategies to challenge Neo-liberalism and reject Neo-liberal ideology.Keywords: neo-liberalism, poverty, employment, poverty reduction, structural adjustment programme
Procedia PDF Downloads 861079 Role of Giardia lamblia Infection in the Pathogenesis of Gastritis in Patients with Dyspepsia
Authors: Aly Kassem, Eman A. Sabet, Hanaa A. El-Hady, Doha S. Mohamed, Abeer Sheneef, Mona Fattouh, Mamdouh M. Esmat
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Objective: Giardia lamblia parasite is the most common protozoal infection in human. Concomitant Helecobacter Pylori (H. pylori) and Giardia lamblia infection is common for their similar mode of transmission and strong correlation to socioeconomic levels. Only few reports had described gastric giardiasis. Our aim was to detect H. pylori and Giardia in gastric antral mucosal biopsies from patients with dyspepsia. The impact of both pathogens on clinical, endoscopic and histopathogical changes was studied. Methods: 48 patients with dyspepsia (group1) and 28 control patients (patients undergoing esophagogastroduodenoscopy EGD for reasons other than dyspepsia), (group 2) were studied. Endoscopic data were reported and gastric biopsy specimens were obtained for subsequent PCR assay for both organisms and for histopathological and electron microscopic examination. Results: Endoscopic antral gastritis and duodenal lesions were found in both groups, however, they were significantly more frequently in group 1 (p= 0.002 and P= 0.0005 respectively). Esophageal lesions, nodular antral gastritis, gastric ulcers and superficial corpal gastritis were found only in group 1. PCR detected H. pylori infection in 58% Vs 64 % for group 1 and group 2 respectively (P: NS). Giardia infection was present in 67 % Vs 42 % for group 1 and group 2 respectively (P=0.0003, Odd ratio=2.6). Co-infection with H. pylori and Giardia was present in 33% of group 1 Vs 36% for group 2 (P:NS). Abnormal histologic findings were found in both groups, however, intestinal metaplasia was found in group 1 only. Cellular abnormalities in the form of cytoplasmic vacuoles, mitochondrial destruction or nuclear abnormalities were found by Electron microscopic study in infected subjects of both groups. Conclusion: H. pylori is not the only gastric pathogen in our community, gastric giardiasis is another pathogen. Its contribution might be a factor in persistent dyspepsia after H. pylori eradication.Keywords: dyspepsia, gastritis, Giardia lamblia, H. pylori
Procedia PDF Downloads 3051078 Performance Analysis of Pumps-as-Turbine Under Cavitating Conditions
Authors: Calvin Stephen, Biswajit Basu, Aonghus McNabola
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Market liberalization in the power sector has led to the emergence of micro-hydropower schemes that are dependent on the use of pumps-as-turbines in applications that were not suitable as potential hydropower sites in earlier years. These applications include energy recovery in water supply networks, sewage systems, irrigation systems, alcohol breweries, underground mining and desalination plants. As a result, there has been an accelerated adoption of pumpsas-turbine technology due to the economic advantages it presents in comparison to the conventional turbines in the micro-hydropower space. The performance of this machines under cavitation conditions, however, is not well understood as there is a deficiency of knowledge in literature focused on their turbine mode of operation. In hydraulic machines, cavitation is a common occurrence which needs to be understood to safeguard them and prolong their operation life. The overall purpose of this study is to investigate the effects of cavitation on the performance of a pumps-as-turbine system over its entire operating range. At various operating speeds, the cavitating region is identified experimentally while monitoring the effects this has on the power produced by the machine. Initial results indicate occurrence of cavitation at higher flow rates for lower operating speeds and at lower flow rates at higher operating speeds. This implies that for cavitation free operation, low speed pumps-as-turbine must be used for low flow rate conditions whereas for sites with higher flow rate conditions high speed turbines should be adopted. Such a complete understanding of pumps-as-turbine suction performance can aid avoid cavitation induced failures hence improved reliability of the micro-hydropower plant.Keywords: cavitation, micro-hydropower, pumps-as-turbine, system design
Procedia PDF Downloads 1191077 A Comparison Study and Analysis on Corporate Social Responsibility among Liner Shipping Companies
Authors: Yu-Sheng Lin, Sheng-Teng Huang
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In recent years, the issue of corporate social responsibility has become an enthusiastic discussion and hottest issue around the world. To make the enterprises be sustainable management and sustainable development, more and more enterprises realize that fulfill its corporate social responsibility is the good choice. It is an essential, important issue that the leader needs know how to lead the staff in balance benefit, also emphasize on economic, social and environmental aspects to impact the company, then enhance the consensus. The leader needs to improve cohesion of personnel, and implement the corporate social responsibility in staff behavior, in order to show a performance in the effort of corporate social responsibility of enterprises. The previous literature mostly is committed to comparison of corporate social responsibility in the industry and service industry, regarding to literature of shipping companies were relatively rare. This paper aims to take the domestic and foreign shipping companies of corporate social responsibility reports as the data analysis, and refer to the international convention (GRI) such as association and organization of CSR standard values. Overall comparison with shipping companies of CSR reports, annual reports and other public information, and taking Taiwan shipping companies as the target, respectively, with the international conventions and the world's top ten leading shipping companies to do the comparison and analysis. Shipping companies in Taiwan are bound to the standard that set by the international convention for the first goal diligently and following step is contend with the world's top ten leading shipping companies. There are 3 ~ 5 experts to be involved in interview after the result is completed. They will indicate the superiority and inferiority then provide the opinion, recommendation in the needed action. Through this study, we can explore the importance of corporate social responsibility report for shipping companies, and also provide the clear orientation to external providers to improve corporate social responsibility. In addition, it can provide the academic research and business experts as a reference; finally, serving shipping companies to complete another contribution.Keywords: Corporate social responsibility (CSR), CSR reports, statistical methods, expert interview method
Procedia PDF Downloads 2921076 Getting to Know the Enemy: Utilization of Phone Record Analysis Simulations to Uncover a Target’s Personal Life Attributes
Authors: David S. Byrne
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The purpose of this paper is to understand how phone record analysis can enable identification of subjects in communication with a target of a terrorist plot. This study also sought to understand the advantages of the implementation of simulations to develop the skills of future intelligence analysts to enhance national security. Through the examination of phone reports which in essence consist of the call traffic of incoming and outgoing numbers (and not by listening to calls or reading the content of text messages), patterns can be uncovered that point toward members of a criminal group and activities planned. Through temporal and frequency analysis, conclusions were drawn to offer insights into the identity of participants and the potential scheme being undertaken. The challenge lies in the accurate identification of the users of the phones in contact with the target. Often investigators rely on proprietary databases and open sources to accomplish this task, however it is difficult to ascertain the accuracy of the information found. Thus, this paper poses two research questions: how effective are freely available web sources of information at determining the actual identification of callers? Secondly, does the identity of the callers enable an understanding of the lifestyle and habits of the target? The methodology for this research consisted of the analysis of the call detail records of the author’s personal phone activity spanning the period of a year combined with a hypothetical theory that the owner of said phone was a leader of terrorist cell. The goal was to reveal the identity of his accomplices and understand how his personal attributes can further paint a picture of the target’s intentions. The results of the study were interesting, nearly 80% of the calls were identified with over a 75% accuracy rating via datamining of open sources. The suspected terrorist’s inner circle was recognized including relatives and potential collaborators as well as financial institutions [money laundering], restaurants [meetings], a sporting goods store [purchase of supplies], and airline and hotels [travel itinerary]. The outcome of this research showed the benefits of cellphone analysis without more intrusive and time-consuming methodologies though it may be instrumental for potential surveillance, interviews, and developing probable cause for wiretaps. Furthermore, this research highlights the importance of building upon the skills of future intelligence analysts through phone record analysis via simulations; that hands-on learning in this case study emphasizes the development of the competencies necessary to improve investigations overall.Keywords: hands-on learning, intelligence analysis, intelligence education, phone record analysis, simulations
Procedia PDF Downloads 141075 Photocapacitor Integrating Solar Energy Conversion and Energy Storage
Authors: Jihuai Wu, Zeyu Song, Zhang Lan, Liuxue Sun
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Solar energy is clean, open, and infinite, but solar radiation on the earth is fluctuating, intermittent, and unstable. So, the sustainable utilization of solar energy requires a combination of high-efficient energy conversion and low-loss energy storage technologies. Hence, a photo capacitor integrated with photo-electrical conversion and electric-chemical storage functions in single device is a cost-effective, volume-effective and functional-effective optimal choice. However, owing to the multiple components, multi-dimensional structure and multiple functions in one device, especially the mismatch of the functional modules, the overall conversion and storage efficiency of the photocapacitors is less than 13%, which seriously limits the development of the integrated system of solar conversion and energy storage. To this end, two typical photocapacitors were studied. A three-terminal photocapacitor was integrated by using perovskite solar cell as solar conversion module and symmetrical supercapacitor as energy storage module. A function portfolio management concept was proposed the relationship among various efficiencies during photovoltaic conversion and energy storage process were clarified. By harmonizing the energy matching between conversion and storage modules and seeking the maximum power points coincide and the maximum efficiency points synchronize, the overall efficiency of the photocapacitor surpassed 18 %, and Joule efficiency was closed to 90%. A voltage adjustable hybrid supercapacitor (VAHSC) was designed as energy storage module, and two Si wafers in series as solar conversion module, a three-terminal photocapacitor was fabricated. The VAHSC effectively harmonizes the energy harvest and storage modules, resulting in the current, voltage, power, and energy match between both modules. The optimal photocapacitor achieved an overall efficiency of 15.49% and Joule efficiency of 86.01%, along with excellent charge/discharge cycle stability. In addition, the Joule efficiency (ηJoule) was defined as the energy ratio of discharge/charge of the devices for the first time.Keywords: joule efficiency, perovskite solar cell, photocapacitor, silicon solar cell, supercapacitor
Procedia PDF Downloads 861074 Determining the Effect of Tdcs in Pain and Quality of Life in Patients with Fibromyalgia
Authors: Farid Rezaei, Zahra Reza Soltani, Behrouz Tavana, Afsaneh Dadarkhah, Masoume Bahrami Asl, S. Alireza Mirghasemi
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Introduction: Fibromyalgia is a syndrome comprised of a group of symptoms. The primary symptom of fibromyalgia is pain propagation is associated by Secondary symptoms include fatigue, cognitive disorders, sleep disorders and hypersensitivity to painful stimuli. Recent studies have shown that there is a direct relationship between fibromyalgia and certain changes in brain activity. Aim: The aim of this study is determining the effect of tDCS in pain and quality of life in patients with fibromyalgia. Method: 68 patients with fibromyalgia who had inclusion criterias were randomly divided into two groups of case and control. Groups were matched in terms of gender, age, education, duration of pain and PMS. Patient groups treated with tDCS device manufacture by Enraf company made in Netherlands (M1 anodal stimulation, 2 mA constant current, 20 minutes, for 10 sessions (3 days a week)). Also the protocol was done for control group, in sham mode of tDCS device that had no current, for 10 sessions of 20 minutes. Before treatment, immediately after the end of 10 sessions treatment (short-term) and 10 week later (long-term effect), pain intensity questionnaires (VAS) and quality of life in fibromyalgia patients questionnaire was completed by the patient. Results: Pain intensity were significantly lower in the treatment group than the sham group 2 weeks and 10 weeks after treatment than before treatment (P < 0.001). Although the quality of life of patients 2 weeks after treatment showed no significant change, but ten weeks after treatment were more than sham group (P < 0.0001). Conclusion: Our results suggest that tDCS is a safe and effective in treating fibromyalgia patients and an important effect in reducing pain and increasing quality of their life.Keywords: fibromyalgia, tDCS, quality of life, VAS score
Procedia PDF Downloads 3411073 Reflecting and Teaching on the Dialectical Nature of Social Work
Authors: Eli Buchbinder
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Dialectics theory perceives two or more forces or themes as mutually opposed and negating on the one hand and as interdependent for their definition, existence, and resolution on the other. Such opposites might never be fully reconciled but might, simultaneously, continue to produce a higher level of integration and synthesis as well as tension, contradictions, and paradoxes. The identity of social work is constructed by poles; an understanding that emerges through key concepts that shape the profession. The key concept of person-in-environment creates dialectical tensions between the psychological versus the social pole. Important examples that reflect this focus on the psychological versus the social nature of human beings. This meta-perspective influences and constructs the implementation of values, ways of intervention, and professional relationships, e.g., creating a conflict between personal/social empowerment and social control and correction as the aims of the profession. Social work is dynamic and changing, with a unique way of perceiving and conceptualizing human behavior. Social workers must be able to face and accept the contradicting elements inherent in practicing social work. The basic philosophy for social work education is a dialectic conceptualization. In light of the above, social work students require dialectics as a critical mode of perception, reflection, and intervention. In the presentation, the focus will be on reflection on teaching students to conceptualize dialectics as a frame when training to be social workers. It is believed that the focus should emphasis two points: 1) the need to assist students to identify poles and to analyze the interrelationships created between them while coping emotionally with the tension and difficulties involved in containing these poles; 2) teaching students to integrate poles as a basis for assessment, planning, and intervention.Keywords: professional ontology, a generic social work education, skills and values of social work, reflecting on social work teaching methods
Procedia PDF Downloads 841072 On Panel Data Analysis of Factors on Economic Advances in Some African Countries
Authors: Ayoola Femi J., Kayode Balogun
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In some African Countries, increase in Gross Domestic Products (GDP) has not translated to real development as expected by common-man in his household. For decades, a lot of contests on economic growth and development has been a nagging issues. The focus of this study is to analysing the effects of economic determinants/factors on economic advances in some African Countries by employing panel data analysis. The yearly (1990-2013) data were obtained from the world economic outlook database of the International Monetary Fund (IMF), for probing the effects of these variables on growth rate in some selected African countries which include: Nigeria, Algeria, Angola, Benin, Botswana, Burundi, Cape-Verde, Cameroun, Central African Republic, Chad, Republic Of Congo, Cote di’ Voire, Egypt, Equatorial-Guinea, Ethiopia, Gabon, Ghana, Guinea Bissau, Kenya, Lesotho, Madagascar, Mali, Mauritius, Morocco, Mozambique, Niger, Rwanda, Senegal, Seychelles, Sierra Leone, South Africa, Sudan, Swaziland, Tanzania, Togo, Tunisia, and Uganda. The effects of 6 macroeconomic variables on GDP were critically examined. We used 37 Countries GDP as our dependent variable and 6 independent variables used in this study include: Total Investment (totinv), Inflation (inf), Population (popl), current account balance (cab), volume of imports of goods and services (vimgs), and volume of exports of goods and services (vexgs). The results of our analysis shows that total investment, population and volume of exports of goods and services strongly affect the economic growth. We noticed that population of these selected countries positively affect the GDP while total investment and volume of exports negatively affect GDP. On the contrary, inflation, current account balance and volume of imports of goods and services’ contribution to the GDP are insignificant. The results of our analysis shows that total investment, population and volume of exports of goods and services strongly affect the economic growth. We noticed that population of these selected countries positively affect the GDP while total investment and volume of exports negatively affect GDP. On the contrary, inflation, current account balance and volume of imports of goods and services’ contribution to the GDP are insignificant. The results of this study would be useful for individual African governments for developing a suitable and appropriate economic policies and strategies. It will also help investors to understand the economic nature and viability of Africa as a continent as well as its individual countries.Keywords: African countries, economic growth and development, gross domestic products, static panel data models
Procedia PDF Downloads 4751071 Synthesis and Characterization of Iron and Aluminum-Containing AFm Phases
Authors: Aurore Lechevallier, Mohend Chaouche, Jerome Soudier, Guillaume Renaudin
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The cement industry accounts for 8% of the global CO₂ emissions, and approximately 60% of these emissions are associated with the Portland cement clinker production from the decarbonization of limestone (CaCO3). Their impact on the greenhouse effect results in growing social awareness. Therefore, CO2 footprint becomes a product selection choice, and substituting Portland cement with a lower CO2-footprint alternative binder is sought. In this context, new hydraulic binders have been studied as a potential Ordinary Portland Cement substitute. Many of them are composed of iron oxides and aluminum oxides, present in the Ca₄Al₂-xFe₂+ₓO₁₀-like phase and forming Ca-LDH (i.e. AFM) as a hydration product. It has become essential to study the possible existence of Fe/Al AFM solid solutions to characterize the hydration process properly. Ca₂Al₂-xFex(OH)₆.X.nH₂O layered AFM samples intercalated with either nitrate or chloride X anions were synthesized based on the co-precipitation method under a nitrogen atmosphere to avoid the carbonation effect.AFM samples intercalated with carbonate anions were synthesized based on the anionic exchange process, using AFM-NO₃ as the source material. These three AFM samples were synthesized with varying Fe/Al molar ratios. The experimental conditions were optimized to make possible the formation of Al-AFM and Fe-AFM using the same parameters (namely pH value and salt concentration). Rietveld refinements were performed to demonstrate the existence of a solid solution between the two trivalent metallic end members. Spectroscopic analyses were used to confirm the intercalation of the targeted anion; secondary electron images were taken to analyze the AFM samples’ morphology, and energy dispersive X-ray spectroscopy (EDX) was carried out to determine the elemental composition of the AFM samples. Results of this study make it possible to quantify the Al/Fe ratio of the AFM phases precipitated in our hydraulic binder, thanks to the determined Vegard's law characteristic to the corresponding solid solutionsKeywords: AFm phase, iron-rich binder, low-carbon cement, solid solution
Procedia PDF Downloads 1371070 Using Variation Theory in a Design-based Approach to Improve Learning Outcomes of Teachers Use of Video and Live Experiments in Swedish Upper Secondary School
Authors: Andreas Johansson
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Conceptual understanding needs to be grounded on observation of physical phenomena, experiences or metaphors. Observation of physical phenomena using demonstration experiments has a long tradition within physics education and students need to develop mental models to relate the observations to concepts from scientific theories. This study investigates how live and video experiments involving an acoustic trap to visualize particle-field interaction, field properties and particle properties can help develop students' mental models and how they can be used differently to realize their potential as teaching tools. Initially, they were treated as analogs and the lesson designs were kept identical. With a design-based approach, the experimental and video designs, as well as best practices for a respective teaching tool, were then developed in iterations. Variation theory was used as a theoretical framework to analyze the planned respective realized pattern of variation and invariance in order to explain learning outcomes as measured by a pre-posttest consisting of conceptual multiple-choice questions inspired by the Force Concept Inventory and the Force and Motion Conceptual Evaluation. Interviews with students and teachers were used to inform the design of experiments and videos in each iteration. The lesson designs and the live and video experiments has been developed to help teachers improve student learning and make school physics more interesting by involving experimental setups that usually are out of reach and to bridge the gap between what happens in classrooms and in science research. As students’ conceptual knowledge also rises their interest in physics the aim is to increase their chances of pursuing careers within science, technology, engineering or mathematics.Keywords: acoustic trap, design-based research, experiments, variation theory
Procedia PDF Downloads 831069 Exploring Communities of Practice through Public Health Walks for Nurse Education
Authors: Jacqueline P. Davies
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Introduction: Student nurses must develop skills in observation, communication and reflection as well as public health knowledge from their first year of training. This paper will explain a method developed for students to collect their own findings about public health in urban areas. These areas are both rich in the history of old public health that informs the content of many traditional public health walks, but are also locations where new public health concerns about chronic disease are concentrated. The learning method explained in this paper enables students to collect their own data and write original work as first year students. Examples of their findings will be given. Methodology: In small groups, health care students are instructed to walk in neighbourhoods near to the hospitals they will soon attend as apprentice nurses. On their walks, they wander slowly, engage in conversations, and enter places open to the public. As they drift, they observe with all five senses in the real three dimensional world to collect data for their reflective accounts of old and new public health. They are encouraged to stop for refreshments and taste, as well as look, hear, smell, and touch while on their walk. They reflect as a group and later develop an individual reflective account in which they write up their deep reflections about what they observed on their walk. In preparation for their walk, they are encouraged to look at studies of quality of Life and other neighbourhood statistics as well as undertaking a risk assessment for their walk. Findings: Reflecting on their walks, students apply theoretical concepts around social determinants of health and health inequalities to develop their understanding of communities in the neighbourhoods visited. They write about the treasured historical architecture made of stone, bronze and marble which have outlived those who built them; but also how the streets are used now. The students develop their observations into thematic analyses such as: what we drink as illustrated by the empty coke can tossed into a now disused drinking fountain; the shift in home-life balance illustrated by streets where families once lived over the shop which are now walked by commuters weaving around each other as they talk on their mobile phones; and security on the street, with CCTV cameras placed at regular intervals, signs warning trespasses and barbed wire; but little evidence of local people watching the street. Conclusion: In evaluations of their first year, students have reported the health walk as one of their best experiences. The innovative approach was commended by the UK governing body of nurse education and it received a quality award from the nurse education funding body. This approach to education allows students to develop skills in the real world and write original work.Keywords: education, innovation, nursing, urban
Procedia PDF Downloads 2871068 The Sub-Optimality of the Electricity Subsidy on Tube Wells in Balochistan (Pakistan): An Analysis Based on Socio-Cultural and Policy Distortions
Authors: Rameesha Javaid
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Agriculture is the backbone of the economy of the province of Balochistan which is known as the ‘fruit basket’ of Pakistan. Its climate zones comprising highlands and plateaus, dependent on rain water, are more suited for the production of deciduous fruit. The vagaries of weather and more so the persistent droughts prompted the government to announce flat rates of electricity bills per month irrespective of the size of the farm, quantum or water used and the category of crop group. That has, no doubt, resulted in increased cropping intensity, more production and employment but has enormously burdened the official exchequer which picks up the residual bills in certain percentages amongst the federal and provincial governments and the local electricity company. This study tests the desirability of continuing the subsidy in the present mode. Optimization of social welfare of farmers has been the focus of the study with emphasis on the contribution of positive externalities and distortions caused in terms of negative externalities. By using the optimization technique with due allowance for distortions, it has been established that the subsidy calls for limiting policy distortions as they cause sub-optimal utilization of the tube well subsidy and improved policy programming. The sensitivity analysis with changed rankings of contributing variables towards social welfare does not significantly change the result. Therefore it leads to the net findings and policy recommendations of significantly reducing the subsidy size, correcting and curtailing policy distortions and targeting the subsidy grant more towards small farmers to generate more welfare by saving a sizeable amount from the subsidy for investment in the wellbeing of the farmers in rural Balochistan.Keywords: distortion, policy distortion, socio-cultural distortion, social welfare, subsidy
Procedia PDF Downloads 292