Search results for: eddy current losses
8009 Maximizing Nitrate Absorption of Agricultural Waste Water in a Tubular Microalgae Reactor by Adapting the Illumination Spectrum
Authors: J. Martin, A. Dannenberg, G. Detrell, R. Ewald, S. Fasoulas
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Microalgae-based photobioreactors (PBR) for Life Support Systems (LSS) are currently being investigated for future space missions such as a crewed base on planets or moons. Biological components may help reducing resupply masses by closing material mass flows with the help of regenerative components. Via photosynthesis, the microalgae use CO2, water, light and nutrients to provide oxygen and biomass for the astronauts. These capabilities could have synergies with Earth applications that tackle current problems and the developed technologies can be transferred. For example, a current worldwide discussed issue is the increased nitrate and phosphate pollution of ground water from agricultural waste waters. To investigate the potential use of a biological system based on the ability of the microalgae to extract and use nitrate and phosphate for the treatment of polluted ground water from agricultural applications, a scalable test stand is being developed. This test stand investigates the maximization of intake rates of nitrate and quantifies the produced biomass and oxygen. To minimize the required energy, for the uptake of nitrate from artificial waste water (AWW) the Flashing Light Effect (FLE) and the adaption of the illumination spectrum were realized. This paper describes the composition of the AWW, the development of the illumination unit and the possibility of non-invasive process optimization and control via the adaption of the illumination spectrum and illumination cycles. The findings were a doubling of the energy related growth rate by adapting the illumination setting.Keywords: microalgae, illumination, nitrate uptake, flashing light effect
Procedia PDF Downloads 1128008 Tourism and Hospitality Education Efficiency Management: The Case of the Tourism Department of Sultan Qaboos University
Authors: Tamer Mohamed Atef
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The tourism and hospitality education is a branch of the overall tourism and hospitality industry that is dedicated to providing the industry with well-educated, well-trained, skilled, enthusiastic and committed workforce. The Tourism Department at the College of Arts and Social Sciences (Sultan Qaboos University), Oman, has been providing the Omani society with undergraduate tourism and hospitality educational services since Fall 2001. Despite the fact that Tourism Department graduates are not facing any employment concerns, fluctuation in the number of enrollees and graduates, however, has been a significant characteristic since the inception of the program. To address this concern, several tactical and strategic decisions have been made, notably that the program has received accreditation from two prestigious international accreditation institutions, which mark two major milestones in the educational journey of the Tourism Department. The current study, thus, aims to provide a tourism and hospitality education efficiency management model. To achieve this aim, the following objectives were identified: to analyze students in - graduates out matrix, and to assess graduates’ employment trends. A survey was conducted to assess the current employment status of the department graduates. Secondary data were collected from Deanship of Admission and Registration statistical reports on the Tourism Department. Data were tabulated and analyzed in such a way that set forth the major findings from the survey and the secondary data. This study sheds light on the educational system created and followed by the Tourism Department, in an effort to provide a tourism and hospitality education efficiency management model, that would help educators and administrators better manage their programs.Keywords: tourism, hospitality, education, students, graduates, employability, indicators
Procedia PDF Downloads 3498007 Digital Interventions for Older People Experiencing Homelessness (OPEH): A Systematic Scoping Review
Authors: Emily Adams, Eddie Donaghy, David Henderson, Lauren Ng, Caroline Sanders, Rowena Stewart, Maria Wolters, Stewart Mercer
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Ongoing review abstract: Older People Experiencing Homelessness (OPEH) can have mental and physical indicators of aging 10–20 years earlier than the general population and experience premature mortality due to age-related chronic conditions. Emerging literature suggests digital interventions could positively impact PEH’s well-being. However, the increased reliance on digital delivery may also perpetuate digital inequalities for socially excluded groups, including PEH. The potential triple disadvantage of being older, homeless, and digitally excluded creates a uniquely problematic situation that warrants further research. This scoping review aims to investigate and synthesise the range and type of digital interventions available to OPEH and the organisations that support OPEH. The following databases were searched on 28th July 2023: Medline, Scopus, International Bibliography of the Social Sciences (IBSS), Applied Social Sciences Index & Abstracts (ASSIA), Association for Computing Machinery Digital Library (ACMDL) and Policy commons. A search strategy was developed in collaboration with an academic librarian. The presentation will include: An introduction to OPEH and digital exclusion Overview of the results of this review: OPEH usage of digital platforms Current digital interventions available The role of support organisations Current gaps in the evidence, future research and recommendations for policy and practiceKeywords: homeless, digital exclusion, aging, technology
Procedia PDF Downloads 788006 Direct CP Violation in Baryonic B-Hadron Decays
Authors: C. Q. Geng, Y. K. Hsiao
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We study direct CP-violating asymmetries (CPAs) in the baryonic B decays of B- -> p\bar{p}M and Λb decays of Λb ®pM andΛb -> J/ΨpM with M=π-, K-,ρ-,K*- based on the generalized factorization method in the standard model (SM). In particular, we show that the CPAs in the vector modes of B-®p\bar{p}K* and Λb -> p K*- can be as large as 20%. We also discuss the simplest purely baryonic decays of Λb-> p\bar{p}n, p\bar{p}Λ, Λ\bar{p}Λ, and Λ\bar{Λ}Λ. We point out that some of CPAs are promising to be measured by the current as well as future B facilities.Keywords: CP violation, B decays, baryonic decays, Λb decays
Procedia PDF Downloads 2558005 Digital Survey to Detect Factors That Determine Successful Implementation of Cooperative Learning in Physical Education
Authors: Carolin Schulze
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Characterized by a positive interdependence of learners, cooperative learning (CL) is one possibility of successfully dealing with the increasing heterogeneity of students. Various positive effects of CL on the mental, physical and social health of students have already been documented. However, this structure is still rarely used in physical education (PE). Moreover, there is a lack of information about factors that determine the successful implementation of CL in PE. Therefore, the objective of the current study was to find out factors that determine the successful implementation of CL in PE using a digital questionnaire that was conducted from November to December 2022. In addition to socio-demographic data (age, gender, teaching experience, and education level), frequency of using CL, implementation strategies (theory-led, student-centred), and positive and negative effects of CL were measured. Furthermore, teachers were asked to rate the success of implementation on a 6-point rating scale (1-very successful to 6-not successful at all). For statistical analysis, multiple linear regression was performed, setting the success of implementation as the dependent variable. A total of 224 teachers (mean age=44.81±10.60 years; 58% male) took part in the current study. Overall, 39% of participants stated that they never use CL in their PE classes. Main reasons against the implementations of CL in PE were no time for preparation (74%) or for implementation (61%) and high heterogeneity of students (55%). When using CL, most of the reported difficulties are related to uncertainties about the correct procedure (54%) and the heterogeneous performance of students (54%). The most frequently mentioned positive effect was increased motivation of students (42%) followed by an improvement of psychological abilities (e.g. self-esteem, self-concept; 36%) and improved class cohesion (31%). Reported negative effects were unpredictability (29%), restlessness (24%), confusion (24%), and conflicts between students (17%). The successful use of CL is related to a theory-based preparation (e.g., heterogeneous formation of groups, use of rules and rituals) and a flexible implementation tailored to the needs and conditions of students (e.g., the possibility of individual work, omission of CL phases). Compared to teachers who solely implemented CL theory-led or student-adapted, teachers who switched from theory-led preparation to student-centred implementation of CL reported more successful implementation (t=5.312; p<.001). Neither frequency of using CL in PE nor the gender, age, the teaching experience, or the education level of the teacher showed a significant connection with the successful use of CL. Corresponding to the results of the current study, it is advisable that teachers gather enough knowledge about CL during their education and to point out the need to adapt the learning structure according to the diversity of their students. In order to analyse implementation strategies of teachers more deeply, qualitative methods and guided interviews with teachers are needed.Keywords: diversity, educational technology, physical education, teaching styles
Procedia PDF Downloads 818004 Solar-Assisted City Bus Electrical Installation: Opportunities and Impact on the Environment in Sydney
Authors: M. J. Geca, T. Tulwin, A. Majczak
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On-board electricity consumption in the diesel city bus during operation is an important energy source. Electricity is generated by a combustion engine-driven alternator. Increased fuel consumption to generate on-board electricity in the bus has a negative impact on the emission of toxic components and carbon dioxide. At the same time, the bus roof surface allows placing a set of lightweight photovoltaic panels with power from 1 to 1.5 kW. The article presents an experimental study of electricity consumption of a city bus with diesel engine equipped with photovoltaic installation. The stream of electricity consumed by the bus and generated by a standard alternator and PV system was recorded. Base on the experimental research carried out in central Europe; the article analyses the impact of an additional source of electricity in the form of a photovoltaic installation on fuel consumption and emissions of toxic components of vehicles located in the latitude of Sydney. In Poland, the maximum global value of horizontal irradiation GHI is 1150 kWh/m², while for Sydney 1652 kWh/m². In addition, the profile of temperature and sunshine per year is different for these two different latitudes as presented in the article. Electricity generated directly from the sun powers the bus's electrical receivers. The photovoltaic system is able to replace 23% of annual electricity consumption, which at the same time will reduce 4% of fuel consumption and CO₂ reduction. Approximately 25% of the light is lost during vehicle traffic in Sydney latitude. The temperature losses of photovoltaic panels are comparable due to the cooling during vehicle motion. Acknowledgement: The project/research was financed in the framework of the project Lublin University of Technology - Regional Excellence Initiative, funded by the Polish Ministry of Science and Higher Education (contract no. 030/RID/2018/19).Keywords: electric energy, photovoltaic system, fuel consumption, CO₂
Procedia PDF Downloads 1138003 Harmonic Distortion Analysis in Low Voltage Grid with Grid-Connected Photovoltaic
Authors: Hedi Dghim, Ahmed El-Naggar, Istvan Erlich
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Power electronic converters are being introduced in low voltage (LV) grids at an increasingly rapid rate due to the growing adoption of power electronic-based home appliances in residential grid. Photovoltaic (PV) systems are considered one of the potential installed renewable energy sources in distribution power systems. This trend has led to high distortion in the supply voltage which consequently produces harmonic currents in the network and causes an inherent voltage unbalance. In order to investigate the effect of harmonic distortions, a case study of a typical LV grid configuration with high penetration of 3-phase and 1-phase rooftop mounted PV from southern Germany was first considered. Electromagnetic transient (EMT) simulations were then carried out under the MATLAB/Simulink environment which contain detailed models for power electronic-based loads, ohmic-based loads as well as 1- and 3-phase PV. Note that, the switching patterns of the power electronic circuits were considered in this study. Measurements were eventually performed to analyze the distortion levels when PV operating under different solar irradiance. The characteristics of the load-side harmonic impedances were analyzed, and their harmonic contributions were evaluated for different distortion levels. The effect of the high penetration of PV on the harmonic distortion of both positive and negative sequences was also investigated. The simulation results are presented based on case studies. The current distortion levels are in agreement with relevant standards, otherwise the Total Harmonic Distortion (THD) increases under low PV power generation due to its inverse relation with the fundamental current.Keywords: harmonic distortion analysis, power quality, PV systems, residential distribution system
Procedia PDF Downloads 2678002 Strategies to Improve Coastal and Marine Tourism Sustainability in Gqeberha, South Africa
Authors: Mihlali Mbangeni, Lynn C. Jonas, Rosemary Matikiti-Manyevere
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Coastal and marine tourism is considered among the most rapidly developing subsectors of tourism. That has enabled coastal and marine environments to gain popularity and economically contribute to coastal regions globally. However, in coastal regions of developing cities such as Gqeberha, South Africa, pollution, specifically plastics and waste from ships, are among the prominent challenges in these areas. Thus, there is a need for the management and planning of sustainability in coastal and marine tourism. As a result, the study evaluates the effectiveness of the current sustainability strategies and highlights the barriers and challenges faced by the coastal region. This study made use of the interpretivist paradigm following a qualitative research approach when collecting data. This was done by conducting semi-structured interviews with local government officials, coastal and marine tourism business top managers, as well as ocean economy-related non-profit organization operators through a purposive sampling method. The study employed content analysis to analyse the interview transcripts using a computer-aided qualitative data analysis software that is Atlas.ti. The research findings present current coastal and marine tourism strategies used, such as local government having quarterly meetings with the private sector promoting collaboration between the two entities. A further measure discovered was non-profit organisations conducting educational talks, workshops, and visiting schools to educate pupils within the coastal region about pollution and sustainability. Current challenges experienced in the implementation of sustainability practices include a lack of awareness, low visibility of the local government in promoting sustainability within the regions, and poor participation of the local community in activities such as beach clean-ups. Recommendations for strategies are to equip decision-makers with knowledge and skills to make informed decisions that are inclusive. Furthermore, local community participation should be encouraged through providing incentives. Local government may also be encouraged to allocate adequate resources to assist non-profit organisations’ efforts towards sustainability. A further recommendation would be for coastal and marine tourism businesses to encourage them to create partnerships as well as collaborate with each other instead of competing in their sustainability efforts. The sharing of information about the sustainability of coastal and marine tourism between non-profit organisations, coastal and marine tourism businesses, local government as well as academia through research publications and ensured implementation, as well as evaluation, can contribute towards the sustainability of Gqeberha’s coastal and marine tourism products.Keywords: coastal and marine tourism threats, coastal and marine tourism trends, strategies for coastal and marine tourism sustainability, sustainability
Procedia PDF Downloads 238001 Comparison of Oven and Microwave Drying on Phenolic Contents and Antioxidant Activities of Red Delicious and Golden Delicious Apples
Authors: Gulcin Yildiz, Gokcen Izli
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Drying (dehydration) is the process of removing water from food in order to preserve the food. Drying is one of the oldest methods known for the preservation of agricultural products such as fruits and vegetables. Drying of agricultural products enhances their storage life, minimizes losses during storage, and save shipping and transportation costs. Apples are considered excellent candidates for drying. The objective of this research was to investigate the effects of microwave and oven processing on the quality of selected apple products. Red delicious and golden delicious apples were washed, peeled, and sliced. Drying experiments were performed in an oven at 50, 75 and 100 °C and in a microwave at 140 W and 210 W. Quality attributes such as color, total phenolic content and antioxidant capacity of dried samples with different methods were compared with the fresh sample. A Minolta CR-300 Chroma Meter was used to examine color changes in the apples. Total phenolic content was determined using the Folin-Ciocalteu reagent. The free radical scavenging activity of the extract was determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH). It was found that the phenolic contents and antioxidant capacities of dried samples under all drying conditions were decreased compared to the fresh samples. The phenolic contents of microwave dried samples at 140 W and 210 W for both red and golden delicious apples were higher than those of the oven drying at 50, 75 and 100 °C. Similarly, the antioxidant activities of microwave dried samples at 140 W and 210 W were higher than those of the oven drying at 50, 75 and 100 °C for both types of apples. All color parameters (L*, a*, b*) were changed significantly depending on the drying methods and temperatures. The closest color values to the fresh sample were found for the microwave dried samples at 140 W. Microwave drying was proven to be more effective than oven drying.Keywords: antioxidant capacity, color, golden delicious, microwave, red delicious, total phenolic content
Procedia PDF Downloads 2368000 Detailed Degradation-Based Model for Solid Oxide Fuel Cells Long-Term Performance
Authors: Mina Naeini, Thomas A. Adams II
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Solid Oxide Fuel Cells (SOFCs) feature high electrical efficiency and generate substantial amounts of waste heat that make them suitable for integrated community energy systems (ICEs). By harvesting and distributing the waste heat through hot water pipelines, SOFCs can meet thermal demand of the communities. Therefore, they can replace traditional gas boilers and reduce greenhouse gas (GHG) emissions. Despite these advantages of SOFCs over competing power generation units, this technology has not been successfully commercialized in large-scale to replace traditional generators in ICEs. One reason is that SOFC performance deteriorates over long-term operation, which makes it difficult to find the proper sizing of the cells for a particular ICE system. In order to find the optimal sizing and operating conditions of SOFCs in a community, a proper knowledge of degradation mechanisms and effects of operating conditions on SOFCs long-time performance is required. The simplified SOFC models that exist in the current literature usually do not provide realistic results since they usually underestimate rate of performance drop by making too many assumptions or generalizations. In addition, some of these models have been obtained from experimental data by curve-fitting methods. Although these models are valid for the range of operating conditions in which experiments were conducted, they cannot be generalized to other conditions and so have limited use for most ICEs. In the present study, a general, detailed degradation-based model is proposed that predicts the performance of conventional SOFCs over a long period of time at different operating conditions. Conventional SOFCs are composed of Yttria Stabilized Zirconia (YSZ) as electrolyte, Ni-cermet anodes, and LaSr₁₋ₓMnₓO₃ (LSM) cathodes. The following degradation processes are considered in this model: oxidation and coarsening of nickel particles in the Ni-cermet anodes, changes in the pore radius in anode, electrolyte, and anode electrical conductivity degradation, and sulfur poisoning of the anode compartment. This model helps decision makers discover the optimal sizing and operation of the cells for a stable, efficient performance with the fewest assumptions. It is suitable for a wide variety of applications. Sulfur contamination of the anode compartment is an important cause of performance drop in cells supplied with hydrocarbon-based fuel sources. H₂S, which is often added to hydrocarbon fuels as an odorant, can diminish catalytic behavior of Ni-based anodes by lowering their electrochemical activity and hydrocarbon conversion properties. Therefore, the existing models in the literature for H₂-supplied SOFCs cannot be applied to hydrocarbon-fueled SOFCs as they only account for the electrochemical activity reduction. A regression model is developed in the current work for sulfur contamination of the SOFCs fed with hydrocarbon fuel sources. The model is developed as a function of current density and H₂S concentration in the fuel. To the best of authors' knowledge, it is the first model that accounts for impact of current density on sulfur poisoning of cells supplied with hydrocarbon-based fuels. Proposed model has wide validity over a range of parameters and is consistent across multiple studies by different independent groups. Simulations using the degradation-based model illustrated that SOFCs voltage drops significantly in the first 1500 hours of operation. After that, cells exhibit a slower degradation rate. The present analysis allowed us to discover the reason for various degradation rate values reported in literature for conventional SOFCs. In fact, the reason why literature reports very different degradation rates, is that literature is inconsistent in definition of how degradation rate is calculated. In the literature, the degradation rate has been calculated as the slope of voltage versus time plot with the unit of voltage drop percentage per 1000 hours operation. Due to the nonlinear profile of voltage over time, degradation rate magnitude depends on the magnitude of time steps selected to calculate the curve's slope. To avoid this issue, instantaneous rate of performance drop is used in the present work. According to a sensitivity analysis, the current density has the highest impact on degradation rate compared to other operating factors, while temperature and hydrogen partial pressure affect SOFCs performance less. The findings demonstrated that a cell running at lower current density performs better in long-term in terms of total average energy delivered per year, even though initially it generates less power than if it had a higher current density. This is because of the dominant and devastating impact of large current densities on the long-term performance of SOFCs, as explained by the model.Keywords: degradation rate, long-term performance, optimal operation, solid oxide fuel cells, SOFCs
Procedia PDF Downloads 1327999 Climate Change and Its Impacts: The Case of Coastal Fishing Communities of the Meghna River in South-Central Bangladesh
Authors: Md. Royhanur Islam, Thomas Cansse, Md. Sahidul Islam, Atiqur Rahman Sunny
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The geographical location of Bangladesh makes it one of the most vulnerable countries to climate change. Climate-induced phenomena mainly affect the south-central region of Bangladesh (Laxmipur district) where they have begun to occur more frequently. The aim of the study was to identify the hydro-climatic factors that lead to weather-related disasters in the coastal areas and analyse the consequences of these factors on coastal livelihoods, with possible adaptation options using participatory rural appraisal (PRA) tools. The present study showed several disasters such as land erosion, depressions and cyclones, coastal flooding, storm surge, and precipitation. The frequency of these disasters is of a noticeable rate. Surveys have also discovered that land erosion is ongoing. Tidal water is being introduced directly into the mainland, and as a result of the salt intrusion, production capacity is declining. The coastal belt is an important area for fishing activities, but due to changed fishing times and a lack of Alternative Income Generating Activities (AIGAs), people have been forced to search for alternative livelihood options by taking both short-term and long-term adaptation options. Therefore, in order to increase awareness and minimize the losses, vulnerable communities must be fully incorporated into disaster response strategies. The government as well as national and international donor organizations should come forward and resolve the present situation of these vulnerable groups since otherwise, they will have to endure endless and miserable suffering due to the effects of climate change ahead in their lives.Keywords: adaptation, community, fishery development, livelihood
Procedia PDF Downloads 1217998 Molecular Characterization of Polyploid Bamboo (Dendrocalamus hamiltonii) Using Microsatellite Markers
Authors: Rajendra K. Meena, Maneesh S. Bhandari, Santan Barthwal, Harish S. Ginwal
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Microsatellite markers are the most valuable tools for the characterization of plant genetic resources or population genetic analysis. Since it is codominant and allelic markers, utilizing them in polyploid species remained doubtful. In such cases, the microsatellite marker is usually analyzed by treating them as a dominant marker. In the current study, it has been showed that despite losing the advantage of co-dominance, microsatellite markers are still a powerful tool for genotyping of polyploid species because of availability of large number of reproducible alleles per locus. It has been studied by genotyping of 19 subpopulations of Dendrocalamus hamiltonii (hexaploid bamboo species) with 17 polymorphic simple sequence repeat (SSR) primer pairs. Among these, ten primers gave typical banding pattern of microsatellite marker as expected in diploid species, but rest 7 gave an unusual pattern, i.e., more than two bands per locus per genotype. In such case, genotyping data are generally analyzed by considering as dominant markers. In the current study, data were analyzed in both ways as dominant and co-dominant. All the 17 primers were first scored as nonallelic data and analyzed; later, the ten primers giving standard banding patterns were analyzed as allelic data and the results were compared. The UPGMA clustering and genetic structure showed that results obtained with both the data sets are very similar with slight variation, and therefore the SSR marker could be utilized to characterize polyploid species by considering them as a dominant marker. The study is highly useful to widen the scope for SSR markers applications and beneficial to the researchers dealing with polyploid species.Keywords: microsatellite markers, Dendrocalamus hamiltonii, dominant and codominant, polyploids
Procedia PDF Downloads 1437997 A Study of Adult Lifelong Learning Consulting and Service System in Taiwan
Authors: Wan Jen Chang
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Back ground: Taiwan's current adult lifelong learning services have expanded from vocational training to universal lifelong learning. However, both the professional knowledge training of learning guidance and consulting services and the provision of adult online learning consulting service systems still need to be established. Purpose: The purposes of this study are as follows: 1. Analyze the professional training mechanism for cultivating adult lifelong learning consultation and coaching; 2. Explore the feasibility of constructing a system that uses network technology to provide adult learning consultation services. Research design: This study conducts a literature analysis of counseling and coaching policy reports on lifelong learning in European countries and the United States. There are two focus discussions were conducted with 15 lifelong learning scholars, experts and practitioners as research subjects. The following two topics were discussed and suggested: 1. The current situation, needs and professional ability training mechanism of "Adult Lifelong Learning Consulting and Services"; 2. Strategies for establishing an "Adult Lifelong Learning Consulting and Service internet System". Conclusion: 1.Based on adult lifelong learning consulting and service needs, plan a professional knowledge training and certification system.2.Adult lifelong learning consulting and service professional knowledge and skills training should include the use of network technology to provide consulting service skills.3.To establish an adult lifelong learning consultation and service system, the Ministry of Education should promulgate policies and measures at the central level and entrust local governments or private organizations to implement them.4.The adult lifelong learning consulting and service system can combine the national qualifications framework, private sector and NPO to expand learning consulting service partners.Keywords: adult lifelong learning, profesional knowledge, consulting and service, network system
Procedia PDF Downloads 677996 An Experimental Quantitative Case Study of Competency-Based Learning in Online Mathematics Education
Authors: Pascal Roubides
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The presentation proposed herein describes a research case study of a hybrid application of the competency-based education model best exemplified by Western Governor’s University, within the general temporal confines of an accelerated (8-week) term of a College Algebra course at the author’s institution. A competency-based model was applied to an accelerated online College Algebra course, built as an Open Educational Resources (OER) course, seeking quantifiable evidence of any differences in the academic achievement of students enrolled in the competency-based course and the academic achievement of the current delivery of the same course. Competency-based learning has been gaining in support in recent times and the author’s institution has also been involved in its own efforts to design and develop courses based on this approach. However, it is unknown whether there had been any research conducted to quantify evidence of the effect of this approach against traditional approaches prior to the author’s case study. The research question sought to answer in this experimental quantitative study was whether the online College Algebra curriculum at the author’s institution delivered via an OER-based competency-based model can produce statistically significant improvement in retention and success rates against the current delivery of the same course. Results obtained in this study showed that there is no statistical difference in the retention rate of the two groups. However, there was a statistically significant difference found between the rates of successful completion of students in the experimental group versus those in the control group.Keywords: competency-based learning, online mathematics, online math education, online courses
Procedia PDF Downloads 1287995 Electrochemical Detection of the Chemotherapy Agent Methotrexate in vitro from Physiological Fluids Using Functionalized Carbon Nanotube past Electrodes
Authors: Shekher Kummari, V. Sunil Kumar, K. Vengatajalabathy Gobi
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A simple, cost-effective, reusable and reagent-free electrochemical biosensor is developed with functionalized multiwall carbon nanotube paste electrode (f-CNTPE) for the sensitive and selective determination of the important chemotherapeutic drug methotrexate (MTX), which is widely used for the treatment of various cancer and autoimmune diseases. The electrochemical response of the fabricated electrode towards the detection of MTX is examined by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and square wave voltammetry (SWV). CV studies have shown that f-CNTPE electrode system exhibited an excellent electrocatalytic activity towards the oxidation of MTX in phosphate buffer (0.2 M) compared with a conventional carbon paste electrode (CPE). The oxidation peak current is enhanced by nearly two times in magnitude. Applying the DPV method under optimized conditions, a linear calibration plot is achieved over a wide range of concentration from 4.0×10⁻⁷ M to 5.5×10⁻⁶ M with the detection limit 1.6×10⁻⁷ M. further, by applying the SWV method a parabolic calibration plot was achieved starting from a very low concentration of 1.0×10⁻⁸ M, and the sensor could detect as low as 2.9×10⁻⁹ M MTX in 10 s and 10 nM were detected in steady state current-time analysis. The f-CNTPE shows very good selectivity towards the specific recognition of MTX in the presence of important biological interference. The electrochemical biosensor detects MTX in-vitro directly from pharmaceutical sample, undiluted urine and human blood serum samples at a concentration range 5.0×10⁻⁷ M with good recovery limits.Keywords: amperometry, electrochemical detection, human blood serum, methotrexate, MWCNT, SWV
Procedia PDF Downloads 3097994 Positivity of Pathogenic Leptospira in Pigs from Rural Communities on the Coast of Ecuador
Authors: Veronica Barragan, Ligia Luna, Maria Patricia Zambrano, Carlos Bulnes, Eduardo Diaz, Talima Pearson
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Leptospirosis impacts animal production and is responsible for important economic losses in the pig industry. Infection is associated with reproductive failures that lead to abortions, stillbirth, and perinatal mortality. The leptospira serogroups that have been traditionally linked to disease in pigs are Pomona, Australis, and Tarassovi. Unfortunately, knowledge about pig leptospirosis is biased towards infection in large-scale commercial farms from developed countries, where exposure is usually limited to host-specific serotypes. The aim of our study is to describe leptospirosis in pigs from rural communities located in the coast of Ecuador-South America, where leptospirosis is endemic. A particularity of these pigs is that, because they are usually raised in the backyard of their owner’s houses, exposure to other leptospira excreted by other animals is likely to occur. Therefore, we collected 420 kidney samples from pigs sacrificed at a local slaughterhouse, and Leptospira positivity was tested in all samples by amplifying the Lipl32 gen. Our results show pathogenic Leptospira positivity in 19.3% (81/420) of pigs. Microaglutination test was performed in 60 PCR positive samples with titers >1:100 in 17 pigs, titers of 1:50 in 28 pigs, and no MAT titers in 15 pigs even though Leptospira DNA was found in their kidneys. Interestingly, reacting serovars were very diverse, with 18.3% of pig sera reacting with two or more serovars. Additionally, serovar Canicola was found in 16.7% of pigs followed by Tarassovi (10%), Australis (6.7%), Pyogenes (5%), Icterohaemorrhageae (1.7%), and Grippotyphosa (1.7%). It is also important to highlight that most of the analyzed animals came from small-scale farms where pigs may be exposed to the pathogen by exposure to other domestic and peridomestic animals such as rats, dogs, horses, donkeys, and even wildlife. This would explain the finding of non-pig adapted Leptospira serovars such as Canicola, which is commonly reported in dogs.Keywords: Leptospira, Lipl32, peridomestic, pig, serovar
Procedia PDF Downloads 1387993 Architecture - Performance Relationship in GPU Computing - Composite Process Flow Modeling and Simulations
Authors: Ram Mohan, Richard Haney, Ajit Kelkar
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Current developments in computing have shown the advantage of using one or more Graphic Processing Units (GPU) to boost the performance of many computationally intensive applications but there are still limits to these GPU-enhanced systems. The major factors that contribute to the limitations of GPU(s) for High Performance Computing (HPC) can be categorized as hardware and software oriented in nature. Understanding how these factors affect performance is essential to develop efficient and robust applications codes that employ one or more GPU devices as powerful co-processors for HPC computational modeling. This research and technical presentation will focus on the analysis and understanding of the intrinsic interrelationship of both hardware and software categories on computational performance for single and multiple GPU-enhanced systems using a computationally intensive application that is representative of a large portion of challenges confronting modern HPC. The representative application uses unstructured finite element computations for transient composite resin infusion process flow modeling as the computational core, characteristics and results of which reflect many other HPC applications via the sparse matrix system used for the solution of linear system of equations. This work describes these various software and hardware factors and how they interact to affect performance of computationally intensive applications enabling more efficient development and porting of High Performance Computing applications that includes current, legacy, and future large scale computational modeling applications in various engineering and scientific disciplines.Keywords: graphical processing unit, software development and engineering, performance analysis, system architecture and software performance
Procedia PDF Downloads 3637992 The Effect of Colloidal Metals Nanoparticles on Quarantine Bacterium - Clavibacter michiganensis Ssp. sepedonicus
Authors: Włodzimierz Przewodowski, Agnieszka Przewodowska
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Colloidal metal nanoparticles have drawn increasing attention in the field of phytopathology because of their unique properties and possibilities of applications. Their antibacterial activity, no induction of the development of pathogen resistance and the ability to penetrate most of biological barriers make them potentially useful in the fighting against dangerous pathogens. These properties are very important in the case of protection of strategic crops in the world, like potato - fourth crop in the world - which is host to numerous pathogenic microorganisms causing serious diseases, significantly affecting yield and causing the economic losses. One of the most important and difficult to reduce pathogen of potato plant is quarantine bacterium Clavibacter michiganensis ssp. sepedonicus (Cms) responsible for ring rot disease. Control and detection of these pathogens is very complicated. Application of healthy, certified seed material as well as hygiene in potato production and storage are the most efficient ways of preventing of ring rot disease. Currently used disinfectants and pesticides, have many disadvantages, such as toxicity, low efficiency, selectivity, corrosiveness, and the inability to eliminate the pathogens in potato tissue. In this situation, it becomes important to search for new formulations based on components harmful to health, yet efficient, stable during prolonged period of time and a with wide range of biocide activity. Such capabilities are offered by the latest generation of biocidal nanoparticles such as colloidal metals. Therefore the aim of the presented research was to develop newly antibacterial preparation based on colloidal metal nanoparticles and checking their influence on the Cms bacteria. Our preliminary results confirmed high efficacy of the nano-colloids in controlling the this selected pathogen.Keywords: clavibacter michiganensis ssp. sepedonicus, colloidal metal nanoparticles, phytopathology, bacteria
Procedia PDF Downloads 2727991 Improved Traveling Wave Method Based Fault Location Algorithm for Multi-Terminal Transmission System of Wind Farm with Grounding Transformer
Authors: Ke Zhang, Yongli Zhu
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Due to rapid load growths in today’s highly electrified societies and the requirement for green energy sources, large-scale wind farm power transmission system is constantly developing. This system is a typical multi-terminal power supply system, whose structure of the network topology of transmission lines is complex. What’s more, it locates in the complex terrain of mountains and grasslands, thus increasing the possibility of transmission line faults and finding the fault location with difficulty after the faults and resulting in an extremely serious phenomenon of abandoning the wind. In order to solve these problems, a fault location method for multi-terminal transmission line based on wind farm characteristics and improved single-ended traveling wave positioning method is proposed. Through studying the zero sequence current characteristics by using the characteristics of the grounding transformer(GT) in the existing large-scale wind farms, it is obtained that the criterion for judging the fault interval of the multi-terminal transmission line. When a ground short-circuit fault occurs, there is only zero sequence current on the path between GT and the fault point. Therefore, the interval where the fault point exists is obtained by determining the path of the zero sequence current. After determining the fault interval, The location of the short-circuit fault point is calculated by the traveling wave method. However, this article uses an improved traveling wave method. It makes the positioning accuracy more accurate by combining the single-ended traveling wave method with double-ended electrical data. What’s more, a method of calculating the traveling wave velocity is deduced according to the above improvements (it is the actual wave velocity in theory). The improvement of the traveling wave velocity calculation method further improves the positioning accuracy. Compared with the traditional positioning method, the average positioning error of this method is reduced by 30%.This method overcomes the shortcomings of the traditional method in poor fault location of wind farm transmission lines. In addition, it is more accurate than the traditional fixed wave velocity method in the calculation of the traveling wave velocity. It can calculate the wave velocity in real time according to the scene and solve the traveling wave velocity can’t be updated with the environment and real-time update. The method is verified in PSCAD/EMTDC.Keywords: grounding transformer, multi-terminal transmission line, short circuit fault location, traveling wave velocity, wind farm
Procedia PDF Downloads 2637990 Contact Toxicity Effects of Different Formulations of Artemisia Absinthium Extracts on Rose Aphid
Authors: Maryam Atapour
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Chemical pesticides, which are widely used in agriculture, cause problems such as soil and water pollution, reducing biodiversity and creating pest resistance. These problems have led to increased attention to alternative and more sustainable methods such as natural-based pesticides. Herbal pesticides have been developed based on essential oils or extracts from different parts of plants, such as leaves, roots, and flowers. Herbal pesticides are compatible with the environment and can be used in integrated pest management programs. Despite the many benefits, herbal pesticides, especially essential oil-based compounds, have low durability in the environment, and their production costs are high, so the use of herbal extracts with appropriate formulations is more justified in all aspects. In the current study and based on the results of previous studies, aqueous and 70% ethanolic extract of Artemisia absinthium L. was prepared by the percolation method and formulated as an emulsion and water-soluble powder. To produce powder formulation, 20% maltodextrin was used with the spray-dryer method. Different concentrations of these compounds were sprayed on bushes infected with rose aphid Macrosiphum rosae (L.). Sampling was done randomly and the percentage of aphids’ mortality was checked. The results showed that the use of different concentrations of ethanolic extracts created a significant difference in the mortality rate of aphids, while water-soluble powder formulation caused less mortality. The current results showed that the extract of this plant has practical usability to control aphids, and with the appropriate formulation, it can be used as a good alternative to chemical pesticides.Keywords: contact toxicity, formulation, extract, aphid, Artemisia absinthium.
Procedia PDF Downloads 377989 Analysis of Labor Behavior Effect on Occupational Health and Safety Management by Multiple Linear Regression
Authors: Yulinda Rizky Pratiwi, Fuji Anugrah Emily
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Management of Occupational Safety and Health (OSH) are appropriately applied properly by all workers and pekarya in the company. K3 management application also has become very important to prevent accidents. Violation of the rules regarding the K3 has often occurred from time to time. By 2015 the number of occurrences of a violation of the K3 or so-called unsafe action tends to increase. Until finally in January 2016, the number increased drastically unsafe action. Trigger increase in the number of unsafe action is a decrease in the quality of management practices K3. While the application of K3 management performed by each individual thought to be influenced by the attitude and observation guide the actions of each of the individual. In addition to the decline in the quality of K3 management application may result in increased likelihood of accidents and losses for the company as well as the local co-workers. The big difference in the number of unsafe action is very significant in the month of January 2016, making the company Pertamina as the national oil company must do a lot of effort to keep track of how the implementation of K3 management on every worker and pekarya, one at PT Pertamina EP Cepu Field Asset IV. To consider the effort to control the implementation of K3 management can be seen from the attitude and observation guide the actions of the workers and pekarya. By using Multiple Linear Regression can be seen the influence of attitude and action observation guide workers and pekarya the K3 management application that has been done. The results showed that scores K3 management application of each worker and pekarya will increase by 0.764 if the score pekarya worker attitudes and increase one unit, whereas if the score Reassurance action guidelines and pekarya workers increased by one unit then the score management application K3 will increase by 0.754.Keywords: occupational safety and health, management of occupational safety and health, unsafe action, multiple linear regression
Procedia PDF Downloads 2307988 The Implementation of Level of Service for Development of Kuala Lumpur Transit Information System using GIS
Authors: Mokhtar Azizi
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Due to heavy traffic and congested roads, it is crucial that the most popular main public transport services in Kuala Lumpur i.e. Putra LRT, Star LRT, KTM Commuter, KL Monorail and Rapid Bus must be continuously monitored and improved to fulfill the rider’s requirement and kept updated by the transit agencies. Evaluation on the current status of the services has been determined out by calculating the transit supportive area (TSA) and level of service (LOS) for each transit station. This research study has carried out the TSA and LOS mapping based on GIS techniques. The detailed census data of the region along the line of services has been collected from the Department of Statistics Malaysia for this purpose. The service coverage has been decided by 400 meters buffer zone for bus stations and 800 meters for rails station and railways in measurement the Quality of Service along the line of services. All the required information has been calculated by using the customized GIS software called Kuala Lumpur Transit Information System (KLTIS). The transit supportive area was calculated with the employment density at least 10 job/hectare or household density at 7.5 unit/hectare and total area covered by transit supportive area is 22516 hectare and the total area that is not supported by transit is 1718 hectare in Kuala Lumpur. The level of service is calculated with the percentage of transit supportive area served by transit for each station. In overall the percentage transit supportive areas served by transit for all the stations were less than 50% which falls in a very low level of service category. This research has proven its benefit by providing the current transit services operators with vital information for improvement of existing public transport services.Keywords: service coverage, transit supportive area, level of service, transit system
Procedia PDF Downloads 3767987 The Need for a Tool to Support Users of E-Science Infrastructures in a Virtual Laboratory Environment
Authors: Hashim Chunpir
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Support processes play an important role to facilitate researchers (users) to accomplish their research activities with the help of cyber-infrastructure(s). However, the current user-support process in cyber-infrastructure needs a feasible tool to support users. This tool must enable the users of a cyber-infrastructure to communicate efficiently with the staffs of a cyber-infrastructure in order to get technical and scientific assistance, whilst saving resources at the same time. This research paper narrates the real story of employing various forms of tools to support the user and staff communication. In addition, this paper projects the lessons learned from an exploration of the help-desk tools in the current state of user support process in Earth System Grid Federation (ESGF) from support staffs’ perspective. ESGF is a climate cyber-infrastructure that facilitates Earth System Modeling (ESM) and is taken as a case study in this paper. Finally, this study proposes a need for a tool, a framework or a platform that not only improves the user support process to address support servicing needs of end-users of e-Science infrastructures but also eases the life of staffs in providing assistance to the users. With the help of such a tool; the collaboration between users and the staffs of cyber-infrastructures is made easier. Consequently, the research activities of the users of e-Science infrastructure will thrive as the scientific and technical support will be available to users. Finally, this results into painless and productive e-Research.Keywords: e-Science User Services, e-Research in Earth Sciences, Information Technology Services Management (ITSM), user support process, service desk, management of support activities, help desk tools, application of social media
Procedia PDF Downloads 4737986 Increasing National Health Insurance Scheme Enrolment in Ghana: Pro-Rata Insurance Premium Payment with Mobile Phone as the Answer
Authors: Joseph Marfo Boaheng, Daniel Ansong, Eugenia Amporfo
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Health Insurance is proposed to provide financial protection against catastrophic health care cost arising from disease. Ghana has had a National Health Insurance Scheme (NHIS) since 2003 with the current enrolment/retention rate of 36%. The main goal of the scheme is to provide equity in the health sector as well as ensuring affordable health care for the poor. However, the current payment system is not flexible to attract significant proportion of the poor informal sector onto the scheme. Looking at the extensive use of mobiles in the Ghana where about 29,220,602.00 registered mobile phone lines are actively in used as of June 2014, paying health insurance premium through mobile phone could be feasible to attract larger proportion of the informal sector onto the scheme. Methodology: The quantitative cross-sectional survey was used to solicit the required information from 877 respondents living in Kumasi, the second capital city of Ghana. The magnitude of the effect of Pro-rata system (flexible payment terms) on NHIS enrollment rate was estimated with binary logistic regression model. Results: The odds for an individual to enroll onto NHIS with mobile phone increases about 2 times more when payment of insurance premium is on pro-rata basis ie. flexible payment terms (p=0.008, CI=1.212-3.565). Conclusion: The study advocates the National Health Insurance Authority consider this alternative payment system that has the potential of attracting a greater proportion of the informal sector to be enrolled or retained onto the scheme.Keywords: enrollment, health insurance, mobile phone, pro-rata
Procedia PDF Downloads 3947985 The Gold Standard Treatment Plan for Vitiligo: A Review on Conventional and Updated Treatment Methods
Authors: Kritin K. Verma, Brian L. Ransdell
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White patches are a symptom of vitiligo, a chronic autoimmune dermatological condition that causes a loss of pigmentation in the skin. Vitiligo can cause issues of self-esteem and quality of life while also progressing the development of other autoimmune diseases. Current treatments in allopathy and homeopathy exist; some treatments have been found to be toxic, whereas others have been helpful. Allopathy has seemed to offer several treatment plans, such as phototherapy, skin lightening preparations, immunosuppressive drugs, combined modality therapy, and steroid medications to improve vitiligo. This presentation will review the FDA-approved topical cream, Opzelura, a JAK inhibitor, and its effects on limiting vitiligo progression. Meanwhile, other non-conventional methods, such as Arsenic Sulphuratum Flavum used in homeopathy, will be debunked based on current literature. Most treatments still serve to arrest progression and induce skin repigmentation. Treatment plans may differ between patients due to depigmentation location on the skin. Since there is no gold standard plan for treating patients with vitiligo, the oral presentation will review all topical and systemic pharmacological therapies that fight the depigmentation of the skin and categorize their validity from a systematic review of the literature. Since treatment plans are limited in nature, all treatment methods will be mentioned and an attempt will be made to make a golden standard treatment process for these patients.Keywords: vitiligo, phototherapy, immunosuppressive drugs, skin lightening preparations, combined modality therapy, arsenic sulphuratum flavum, homeopathy, allopathy, golden standard, Opzelura
Procedia PDF Downloads 867984 Spatio-Temporal Changes of Rainfall in São Paulo, Brazil (1973-2012): A Gamma Distribution and Cluster Analysis
Authors: Guilherme Henrique Gabriel, Lucí Hidalgo Nunes
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An important feature of rainfall regimes is the variability, which is subject to the atmosphere’s general and regional dynamics, geographical position and relief. Despite being inherent to the climate system, it can harshly impact virtually all human activities. In turn, global climate change has the ability to significantly affect smaller-scale rainfall regimes by altering their current variability patterns. In this regard, it is useful to know if regional climates are changing over time and whether it is possible to link these variations to climate change trends observed globally. This study is part of an international project (Metropole-FAPESP, Proc. 2012/51876-0 and Proc. 2015/11035-5) and the objective was to identify and evaluate possible changes in rainfall behavior in the state of São Paulo, southeastern Brazil, using rainfall data from 79 rain gauges for the last forty years. Cluster analysis and gamma distribution parameters were used for evaluating spatial and temporal trends, and the outcomes are presented by means of geographic information systems tools. Results show remarkable changes in rainfall distribution patterns in São Paulo over the years: changes in shape and scale parameters of gamma distribution indicate both an increase in the irregularity of rainfall distribution and the probability of occurrence of extreme events. Additionally, the spatial outcome of cluster analysis along with the gamma distribution parameters suggest that changes occurred simultaneously over the whole area, indicating that they could be related to remote causes beyond the local and regional ones, especially in a current global climate change scenario.Keywords: climate change, cluster analysis, gamma distribution, rainfall
Procedia PDF Downloads 3197983 Psycho-Social Problems Faced by Transgenders in Pakistani Society: A Qualitative Study
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In the social, behavioral, and medical sciences, and particularly in Pakistani popular culture and political discourse, transgender issues are a relatively recent subject of research. The present study aimed to explore the lived experiences related to psycho-social issues faced by transgenders in Pakistani society. In this qualitative study, phenomenology research design was used. The purposive and snowball sampling techniques were used for data collection and in-depth interviews were conducted with N= 8 transgenders belonging to Lahore city, Pakistan. All interviews were audio recorded and transcribed properly. Interpretative phenomenological analysis was used to generate results in terms of themes. The results of the current study revealed different major themes such as psychological, social, and financial problems. Several emergent and sub-themes were also generated such as insomnia, suicidal ideation, stress, physical abuse, social rejection, discrimination at work workplace, less job opportunities, and harassment. Current study indicate that transgender suffer from different problems and struggle hard for their daily living. It was concluded that there should be a step taken at government level for the betterment of this community. The findings of the present study can help out transgender communities and activist to uncover their problem and empowering transgender individuals through education, skill development, and opportunities for growth. Their abilities can be utilized by providing education, polishing their skills, and employment opportunities. The data provides the knowledge that there should be strategies at family, society and government level for the betterment of transgenders.Keywords: psychological issues, social issues, financial issues, transgender, Pakistani society
Procedia PDF Downloads 247982 Psycho-Social Problems Faced by Transgenders in Pakistani Society: A Qualitative Study”
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In the social, behavioral, and medical sciences, and particularly in Pakistani popular culture and political discourse, transgender issues are a relatively recent subject of research. The present study aimed to explore the lived experiences related to psycho-social issues faced by transgenders in Pakistani society. In this qualitative study, phenomenology research design was used. The purposive and snowball sampling techniques were used for data collection and in-depth interviews were conducted with N= 8 transgenders belonging to Lahore city, Pakistan. All interviews were audio recorded and transcribed properly. Interpretative phenomenological analysis was used to generate results in terms of themes. The results of the current study revealed different major themes such as psychological, social, and financial problems. Several emergent and sub-themes were also generated such as insomnia, suicidal ideation, stress, physical abuse, social rejection, discrimination at work workplace, less job opportunities, and harassment. Current study indicate that transgender suffer from different problems and struggle hard for their daily living. It was concluded that there should be a step taken at government level for the betterment of this community. The findings of the present study can help out transgender communities and activist to uncover their problem and empowering transgender individuals through education, skill development, and opportunities for growth. Their abilities can be utilized by providing education, polishing their skills, and employment opportunities. The data provides the knowledge that there should be strategies at family, society and government level for the betterment of transgenders.Keywords: psychological issues, social issues, financial issues, transgender, Pakistani society
Procedia PDF Downloads 317981 The Increase of Adolescent Obesity Rates after the COVID-19 Pandemic and Possible Obesity Prevention Programs for Implementation
Authors: Tatiana Pratt, Benyamin Hanasabzadeh, Panayiota Courelli
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The COVID-19 pandemic is one of the largest global public health issues of this current century. COVID-19 puts people diagnosed with obesity at higher risk of not only contracting the virus but also being hospitalized and dying, making this a vital time to implement obesity prevention programs. However, COVID-19 is predicted to rapidly increase the obesity rate in the United States due to the mandatory sedentary lifestyle the pandemic demands; this is especially harmful to adolescent-aged children because it creates lifelong unhealthy habits and behaviors. Adolescent obesity prevention programs have been rigorously implemented throughout the last century to help diminish the ever-increasing adolescent obesity rate. Since the pandemic kept adolescents inside and away from in-person school, many programs have now become ineffective due to their in-person participation. Examples of in-person participation programs include school lunch programs, OSNAP and New Moves. Therefore, online programs or remote intervention measures are now more essential. This leads to programs such as Time2bHealthy, HEALTH[e]TEEN, and SWITCH should be looked at with more vitality. Adolescents have intertwined their lives with technology and screen usage. Therefore, online and remote prevention programs will continue to play a large role in the post-pandemic era. This literature review will be reviewing past and current adolescent obesity prevention programs and their effectiveness with the new remote, sedentary lifestyle adolescents. Furthermore, it will suggest new ways to more productively decrease adolescent obesity rates by analyzing the harmful factors that COVID-19 introduced into their lifestyles.Keywords: adolescent, obesity, overweight, COVID-19, preventative care, public health, public policy, obesity prevention programs, online programs
Procedia PDF Downloads 2387980 Nano-Filled Matrix Reinforced by Woven Carbon Fibers Used as a Sensor
Authors: K. Hamdi, Z. Aboura, W. Harizi, K. Khellil
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Improving the electrical properties of organic matrix composites has been investigated in several studies. Thus, to extend the use of composites in more varied application, one of the actual barrier is their poor electrical conductivities. In the case of carbon fiber composites, organic matrix are in charge of the insulating properties of the resulting composite. However, studying the properties of continuous carbon fiber nano-filled composites is less investigated. This work tends to characterize the effect of carbon black nano-fillers on the properties of the woven carbon fiber composites. First of all, SEM observations were performed to localize the nano-particles. It showed that particles penetrated on the fiber zone (figure1). In fact, by reaching the fiber zone, the carbon black nano-fillers created network connectivity between fibers which means an easy pathway for the current. It explains the noticed improvement of the electrical conductivity of the composites by adding carbon black. This test was performed with the four points electrical circuit. It shows that electrical conductivity of 'neat' matrix composite passed from 80S/cm to 150S/cm by adding 9wt% of carbon black and to 250S/cm by adding 17wt% of the same nano-filler. Thanks to these results, the use of this composite as a strain gauge might be possible. By the way, the study of the influence of a mechanical excitation (flexion, tensile) on the electrical properties of the composite by recording the variance of an electrical current passing through the material during the mechanical testing is possible. Three different configuration were performed depending on the rate of carbon black used as nano-filler. These investigation could lead to develop an auto-instrumented material.Keywords: carbon fibers composites, nano-fillers, strain-sensors, auto-instrumented
Procedia PDF Downloads 411