Search results for: evolution strategies
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 7026

Search results for: evolution strategies

2076 Voltage Stabilization of Hybrid PV and Battery Systems by Considering Temperature and Irradiance Changes in Standalone Operation

Authors: S. Jalilzadeh, S. M. Mohseni Bonab

Abstract:

Solar and battery energy storage systems are very useful for consumers who live in deprived areas and do not have access to electricity distribution networks. Nowadays one of the problems that photo voltaic systems (PV) have changing of output power in temperature and irradiance variations, which directly affects the load that is connected to photo voltaic systems. In this paper, with considering the fact that the solar array varies with change in temperature and solar power radiation, a voltage stabilizer system of a load connected to photo voltaic array is designed to stabilize the load voltage and to transfer surplus power of the battery. Also, in proposed hybrid system, the needed load power amount is supplemented considering the voltage stabilization in standalone operation for supplying unbalanced AC load. Electrical energy storage system for voltage control and improvement of the performance of PV by a DC/DC converter is connected to the DC bus. The load is also feed by an AC/DC converter. In this paper, when the voltage increases in its reference limit, the battery gets charged by the photo voltaic array and when it decreases in its defined limit, the power gets injected to the DC bus by this battery. The constant of DC bus Voltage is the cause for the reduced harmonics generated by the inverter. In addition, a series of filters are provided in the inverter output in to reduced harmonics. The inverter control circuit is designed that the voltage and frequency of the load remain almost constant at different load conditions. This paper has focused on controlling strategies of converters to improve their performance.

Keywords: photovoltaic array (PV), DC/DC Boost converter, battery converter, inverters control

Procedia PDF Downloads 483
2075 Incidences and Chemico-Mobility of Toxic Heavy Metals in Environmental Samples

Authors: I. Hilia, C. Hange, F. Hakala, M. Matheus, C. Jansen, J. Hidinwa, O. Awofolu

Abstract:

The article reports on the occurrences, level, and mobility of selected trace metals in environmental samples. The conceptual basis was to examine the possible influence of anthropogenic activities and the impact on human and environmental health. Environmental samples (soil, plant and lower animal) were randomly collected from stratified study/sampling areas, preserved and pre-treated before analysis. Mineral acid digestion procedure was employed for the isolation of metallic contents in samples, and elemental qualitative and quantitative analysis was by ICP-OES. Analytical protocol was validated through the quality assurance process and was found acceptable with quantitative metallic recoveries in the range of 85-90%; hence considered applicable for the analyses of environmental samples. The mean concentration of analysed metals in soil samples ranged from 53.2- 2532.8 mg/kg (Cu); 59.5- 2020.1 mg/kg (Zn); 1.80 – 21.26 mg/kg (Cd) and 19.6- 140.9 mg/kg (Pb). The mean level in grass samples ranged from 9.33 – 38.63 mg/kg (Cu); 64.20-105.18 mg/kg (Zn); 0.28–0.73 mg/kg (Cd) and 0.53 -16.26 mg/kg (Pb) while the mean level in lower animal sample (beetle) varied from 9.6 - 105.3 mg/kg (Cu); 134.1-297.2 mg/kg (Zn); 0.63 – 3.78 (Cd) and 8.0 – 29.1 mg/kg (Pb) across sample collection points (SCPs) 1-4 respectively. Metallic transfer factors (TFs) were in the order Zn >Cd > Cu > Pb with metal Pollution Indices (MPIs) in the order SCP1 > SCP2 > SCP3 > SCP4. About 60-70 % of analysed metals were above the maximum allowable limits (MALs) in soil and plant samples. Results obtained revealed the general prevalence of analysed metals at all sampled sites with indication of metallic mobility across the food chain which portrayed dire consequences for environmental and human health. Systematic environmental remediation and pollution abatement strategies are recommended.

Keywords: trace metals, pollution, human health, Incidences, ICP-OES

Procedia PDF Downloads 157
2074 Using Possibility Books to Develop Creativity Mindsets - a New Pedagogy for Learning Science, Math, and Engineering

Authors: Michael R. Taber, Kristin Stanec

Abstract:

This paper presents year-two of a longitudinal study on implementing Possibility Books into undergraduate courses to develop a student's creativity mindset: tolerating ambiguity, willingness to risk failure, curiosity, and openness to embrace possibility thinking through unexpected connections. Courses involved in this research span disciplines in the natural and social sciences and the humanities. Year one of the project developed indices from which baseline data could be analyzed. The two significant indices ( > 0.7) were "creativity mindset" and "intentional interactions." Preliminary qualitative and quantitative data analysis indicated that students found the new pedagogical intervention as a safe space to learn new strategies, recognize patterns, and define structures through innovative notetaking forms. Possibility Books in Natural Science courses were designed to develop students' conceptualization of science and math. Using Possibility Books in all disciplines provided a space for students to practice divergent thinking (i.e.,Possibilities), convergent thinking (i.e., forms that express meaning), and risk-taking (i.e., the vulnerability associated with expression). Qualitative coding of open responses on a post-survey revealed two major themes: 1) Possibility Books provided a mind space for learning about self, and 2) provided a calming opportunity to connect concepts. Quantitative analysis indicated significant correlations between focused headspace and notetaking (r = 0.555, p < 0.001), focused headspace, and connecting with others (r = 0.405, p < 0.001).

Keywords: pedagogy, science education, learning methods, creativity mindsets

Procedia PDF Downloads 16
2073 Perspectives of Pre-service Teachers on Vocational Pedagogy in Technical and Vocational Education and Training Teaching

Authors: Siphokazi Vimbelo

Abstract:

Abstract - TVET colleges were established to equip students with the necessary skills for careers in a variety of fields such as business, tourism, engineering, and hospitality. TVET teachers are responsible for preparing students and for ensuring that students acquire these necessary skills. This calls for the pedagogies currently utilized in the TVET classroom. Occupational programmes that are being introduced in TVET colleges in South Africa will necessitate vocational pedagogy, which focuses on how individuals learn effectively in skill-oriented knowledge areas. Furthermore, limited research exists on the obstacles encountered by pre-service TVET educators as they develop vocational pedagogy-based lessons. Hence, this research will specifically examine the difficulties encountered by pre-service teachers in creating lesson plans rooted in vocational teaching methods. The preservice teachers are the students in the first year of the Advanced Diploma in Technical and Vocational Teaching (ADTVT). After brainstorming vocational pedagogy, the preservice teachers will develop lessons rooted in vocational pedagogy. Following that, the preservice teachers will participate in interviews to reflect on their lesson preparation process and discuss the challenges they encountered during the preparation. Thematic analysis will be used to analyse the data. It would be fascinating to discover the obstacles and exchange thoughts with academics from other Higher Education Institutions (HEIs) that also provide the same course, since it is a new program. Furthermore, the results will assist Cape Peninsula University of Technology (CPUT) academics in partnering with other academics to create various strategies for tackling challenges and determining priorities in implementing vocational education for a new student population.

Keywords: preservice teachers, TVET, TVET teaching, vocational pedagogy

Procedia PDF Downloads 65
2072 Validating the Micro-Dynamic Rule in Opinion Dynamics Models

Authors: Dino Carpentras, Paul Maher, Caoimhe O'Reilly, Michael Quayle

Abstract:

Opinion dynamics is dedicated to modeling the dynamic evolution of people's opinions. Models in this field are based on a micro-dynamic rule, which determines how people update their opinion when interacting. Despite the high number of new models (many of them based on new rules), little research has been dedicated to experimentally validate the rule. A few studies started bridging this literature gap by experimentally testing the rule. However, in these studies, participants are forced to express their opinion as a number instead of using natural language. Furthermore, some of these studies average data from experimental questions, without testing if differences existed between them. Indeed, it is possible that different topics could show different dynamics. For example, people may be more prone to accepting someone's else opinion regarding less polarized topics. In this work, we collected data from 200 participants on 5 unpolarized topics. Participants expressed their opinions using natural language ('agree' or 'disagree') and the certainty of their answer, expressed as a number between 1 and 10. To keep the interaction based on natural language, certainty was not shown to other participants. We then showed to the participant someone else's opinion on the same topic and, after a distraction task, we repeated the measurement. To produce data compatible with standard opinion dynamics models, we multiplied the opinion (encoded as agree=1 and disagree=-1) with the certainty to obtain a single 'continuous opinion' ranging from -10 to 10. By analyzing the topics independently, we observed that each one shows a different initial distribution. However, the dynamics (i.e., the properties of the opinion change) appear to be similar between all topics. This suggested that the same micro-dynamic rule could be applied to unpolarized topics. Another important result is that participants that change opinion tend to maintain similar levels of certainty. This is in contrast with typical micro-dynamics rules, where agents move to an average point instead of directly jumping to the opposite continuous opinion. As expected, in the data, we also observed the effect of social influence. This means that exposing someone with 'agree' or 'disagree' influenced participants to respectively higher or lower values of the continuous opinion. However, we also observed random variations whose effect was stronger than the social influence’s one. We even observed cases of people that changed from 'agree' to 'disagree,' even if they were exposed to 'agree.' This phenomenon is surprising, as, in the standard literature, the strength of the noise is usually smaller than the strength of social influence. Finally, we also built an opinion dynamics model from the data. The model was able to explain more than 80% of the data variance. Furthermore, by iterating the model, we were able to produce polarized states even starting from an unpolarized population. This experimental approach offers a way to test the micro-dynamic rule. This also allows us to build models which are directly grounded on experimental results.

Keywords: experimental validation, micro-dynamic rule, opinion dynamics, update rule

Procedia PDF Downloads 154
2071 A Study of Adult Lifelong Learning Consulting and Service System in Taiwan

Authors: Wan Jen Chang

Abstract:

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 64
2070 Secondary Traumatic Stress and Related Factors in Australian Social Workers and Psychologists

Authors: Cindy Davis, Samantha Rayner

Abstract:

Secondary traumatic stress (STS) is an indirect form of trauma affecting the psychological well-being of mental health workers; STS is found to be a prevalent risk in mental health occupations. Various factors impact the development of STS within the literature; including the level of trauma individuals are exposed to and their level of empathy. Research is limited on STS in mental health workers in Australia; therefore, this study examined STS and related factors of empathetic behavior and trauma caseload among mental health workers. The research utilized an online survey quantitative research design with a purposive sample of 190 mental health workers (176 females) recruited via professional websites and unofficial social media groups. Participants completed an online questionnaire comprising of demographics, the secondary traumatic stress scale and the empathy scale for social workers. A standard hierarchical regression analysis was conducted to examine the significance of covariates, traumatized clients, traumatic stress within workload and empathy in predicting STS. The current research found 29.5% of participants to meet the criteria for a diagnosis of STS. Age and past trauma within the covariates were significantly associated with STS. Amount of traumatized clients significantly predicted 4.7% of the variance in STS, traumatic stress within workload significantly predicted 4.8% of the variance in STS and empathy significantly predicted 4.9% of the variance in STS. These three independent variables and the covariates accounted for 18.5% of the variance in STS. Practical implications include a focus on developing risk strategies and treatment methods that can diminish the impact of STS.

Keywords: mental health, PTSD, social work, trauma

Procedia PDF Downloads 330
2069 Investigation of a Single Feedstock Particle during Pyrolysis in Fluidized Bed Reactors via X-Ray Imaging Technique

Authors: Stefano Iannello, Massimiliano Materazzi

Abstract:

Fluidized bed reactor technologies are one of the most valuable pathways for thermochemical conversions of biogenic fuels due to their good operating flexibility. Nevertheless, there are still issues related to the mixing and separation of heterogeneous phases during operation with highly volatile feedstocks, including biomass and waste. At high temperatures, the volatile content of the feedstock is released in the form of the so-called endogenous bubbles, which generally exert a “lift” effect on the particle itself by dragging it up to the bed surface. Such phenomenon leads to high release of volatile matter into the freeboard and limited mass and heat transfer with particles of the bed inventory. The aim of this work is to get a better understanding of the behaviour of a single reacting particle in a hot fluidized bed reactor during the devolatilization stage. The analysis has been undertaken at different fluidization regimes and temperatures to closely mirror the operating conditions of waste-to-energy processes. Beechwood and polypropylene particles were used to resemble the biomass and plastic fractions present in waste materials, respectively. The non-invasive X-ray technique was coupled to particle tracking algorithms to characterize the motion of a single feedstock particle during the devolatilization with high resolution. A high-energy X-ray beam passes through the vessel where absorption occurs, depending on the distribution and amount of solids and fluids along the beam path. A high-speed video camera is synchronised to the beam and provides frame-by-frame imaging of the flow patterns of fluids and solids within the fluidized bed up to 72 fps (frames per second). A comprehensive mathematical model has been developed in order to validate the experimental results. Beech wood and polypropylene particles have shown a very different dynamic behaviour during the pyrolysis stage. When the feedstock is fed from the bottom, the plastic material tends to spend more time within the bed than the biomass. This behaviour can be attributed to the presence of the endogenous bubbles, which drag effect is more pronounced during the devolatilization of biomass, resulting in a lower residence time of the particle within the bed. At the typical operating temperatures of thermochemical conversions, the synthetic polymer softens and melts, and the bed particles attach on its outer surface, generating a wet plastic-sand agglomerate. Consequently, this additional layer of sand may hinder the rapid evolution of volatiles in the form of endogenous bubbles, and therefore the establishment of a poor drag effect acting on the feedstock itself. Information about the mixing and segregation of solid feedstock is of prime importance for the design and development of more efficient industrial-scale operations.

Keywords: fluidized bed, pyrolysis, waste feedstock, X-ray

Procedia PDF Downloads 166
2068 Phylogenetic Inferences based on Morphoanatomical Characters in Plectranthus esculentus N. E. Br. (Lamiaceae) from Nigeria

Authors: Otuwose E. Agyeno, Adeniyi A. Jayeola, Bashir A. Ajala

Abstract:

P. esculentus is indigenous to Nigeria yet no wild relation has been encountered or reported. This has made it difficult to establish proper lineages between the varieties and landraces under cultivation. The present work is the first to determine the apormophy of 135 morphoanatomical characters in organs of 46 accessions drawn from 23 populations of this species based on dicta. The character states were coded in accession x character-state matrices and only 83 were informative and utilised for neighbour joining clustering based on euclidean values, and heuristic search in parsimony analysis using PAST ver. 3.15 software. Compatibility and evolutionary trends between accessions were then explored from values and diagrams produced. The low consistency indices (CI) recorded support monophyly and low homoplasy in this taxon. Agglomerative schedules based on character type and source data sets divided the accessions into mainly 3 clades, each of complexes of accessions. Solenostemon rotundifolius (Poir) J.K Morton was the outgroup (OG) used, and it occurred within the largest clades except when the characters were combined in a data set. The OG showed better compatibility with accessions of populations of landrace Isci, and varieties Riyum and Long’at. Otherwise, its aerial parts are more consistent with those of accessions of variety Bebot. The highly polytomous clades produced due to anatomical data set may be an indication of how stable such characters are in this species. Strict consensus trees with more than 60 nodes outputted showed that the basal nodes were strongly supported by 3 to 17 characters across the data sets, suggesting that populations of this species are more alike. The OG was clearly the first diverging lineage and closely related to accessions of landrace Gwe and variety Bebot morphologically, but different from them anatomically. It was also distantly related to landrace Fina and variety Long’at in terms of root, stem and leaf structural attributes. There were at least 5 other clades with each comprising of complexes of accessions from different localities and terrains within the study area. Spherical stem in cross section, size of vascular bundles at the stem corners as well as the alternate and whorl phyllotaxy are attributes which may have facilitated each other’s evolution in all accessions of the landrace Gwe, and they may be innovative since such states are not characteristic of the larger Lamiaceae, and Plectranthus L’Her in particular. In conclusion, this study has provided valuable information about infraspecific diversity in this taxon. It supports recognition of the varietal statuses accorded to populations of P. esculentus, as well as the hypothesis that the wild gene might have been distributed on the Jos Plateau. However, molecular characterisation of accessions of populations of this species would resolve this problem better.

Keywords: clustering, lineage, morphoanatomical characters, Nigeria, phylogenetics, Plectranthus esculentus, population

Procedia PDF Downloads 133
2067 Addressing Ophthalmic and Vascular Diabetic Complications in South Asians

Authors: Haaris Khan, Farhad Udwadia

Abstract:

South Asians are the fastest-growing immigrant population in Canada and are 3-4 times more likely to develop diabetes. In a primary care setting, language barriers continue to persist as a prominent obstacle when delivering crucial health information. Given the abundance of languages in the South Asian community and the varying levels of English fluency, there is compelling evidence that these language barriers can adversely impact health outcomes. The microvascular and macrovascular complications of poor diabetic management are well established and universally recognized. However, these are often difficult concepts to grasp for even individuals fluent in English. In order to lessen the burden of language barriers, we developed a comprehensive guide in various languages that discuss the complications and screening guidelines for diabetic and prediabetic patients. The guide is presented in the form of a pamphlet, with an electronic version being constructed as well, that provides basic information on diabetic retinopathy, neuropathy and nephropathy as well as the screening recommendations. We also conducted a review of the literature around the topic and incorporated our findings into our project. Our goal is for primary care physicians to have this resource and to be able to provide the link or pamphlet to patients in need. Our presentation also provides a comprehensive overview of some of the other barriers that individuals in the South Asian community face when seeking care. Given the staggering number of individuals in the South Asian community with diabetes and the morbidity and mortality associated with diabetes and its complications, effective community-specific strategies are needed to mitigate the potential consequences of poor diabetes management.

Keywords: diabetes, patient education, ophthalmology, vascular surgery

Procedia PDF Downloads 205
2066 Distributed Generation Connection to the Network: Obtaining Stability Using Transient Behavior

Authors: A. Hadadi, M. Abdollahi, A. Dustmohammadi

Abstract:

The growing use of DGs in distribution networks provide many advantages and also cause new problems which should be anticipated and be solved with appropriate solutions. One of the problems is transient voltage drop and short circuit in the electrical network, in the presence of distributed generation - which can lead to instability. The appearance of the short circuit will cause loss of generator synchronism, even though if it would be able to recover synchronizing mode after removing faulty generator, it will be stable. In order to increase system reliability and generator lifetime, some strategies should be planned to apply even in some situations which a fault prevent generators from separation. In this paper, one fault current limiter is installed due to prevent DGs separation from the grid when fault occurs. Furthermore, an innovative objective function is applied to determine the impedance optimal amount of fault current limiter in order to improve transient stability of distributed generation. Fault current limiter can prevent generator rotor's sudden acceleration after fault occurrence and thereby improve the network transient stability by reducing the current flow in a fast and effective manner. In fact, by applying created impedance by fault current limiter when a short circuit happens on the path of current injection DG to the fault location, the critical fault clearing time improve remarkably. Therefore, protective relay has more time to clear fault and isolate the fault zone without any instability. Finally, different transient scenarios of connection plan sustainability of small scale synchronous generators to the distribution network are presented.

Keywords: critical clearing time, fault current limiter, synchronous generator, transient stability, transient states

Procedia PDF Downloads 193
2065 Local Development and Community Participation in Owo Local Government Area of Ondo State, Nigeria

Authors: Tolu Lawal

Abstract:

The genuine development of the grassroots particularly in the developing societies depends largely on the participation of the rural populace in policy conception and implementation, especially in the area of development policies, fundamentally, the rural people play a vital and significance role in economic and political development of the nation. This is because the bulk of the economic produce as well as votes come from these areas. However, the much needed development has continued to elude the rural communities inspire of the various development policies carried out by successive governments in the state. The exclusion of rural communities from planning and implementation of facilities meant to benefit them, and the international debate on sustainable rural development led Ondo State government to re-think its rural development policy with a view to establishing more effective strategies for rural development. The 31s initiatives introduced in 2009 emphasizes the important role of communities in their own development. The paper therefore critically assessed the 31s initiative of the present government in Ondo State with a view to knowing its impact on rural people. The study adopted both primary and secondary data to source its information. Interviews were conducted with the key informants, and field survey (visit) was also part of method of collecting data. Documents, reports and records on 31s initiatives in the selected villages and from outside were also consulted. The paper submitted that 31s initiative has not impacted positively on the lives of rural dwellers in Ondo-State, most especially in the areas of infrastructure and integrated development. The findings also suggested that 31s initiatives is not hopeless, but needs a different kind of investment, for example introducing measures of accountability, addressing the politicization of the initiative and exploiting key principles of development and service delivery.

Keywords: development, infrastructure, rural development, participation

Procedia PDF Downloads 305
2064 Childhood Trauma and Borderline Personality: An Analysis of the Root Causes and Treatment Plans

Authors: Sidika McNeil

Abstract:

Borderline personality disorder (BPD) is a personality disorder that has been found to have strong origins in childhood trauma. One of the key symptoms of BPD is an association with irregular moods swings, as well as suicidal ideation (SI). Owing to the typically severe trauma patients experience during childhood, it is hard for them to control their emotions and thus makes it hard to emotionally regulate. It is then very common for those suffering from BPD to turn to unhealthy coping mechanisms, such as substance use, unhealthy relationships, and more, often unsuccessfully creating experiences that facilitate safety which leads to further negative experiences. With the high suicide rating among children, adolescents, and teens, and an ever-increasing number of children being diagnosed with BPD, it is very important that more research is done to find further treatments for patients who are currently suffering. Methods: Utilizing data found in prior studies, this paper will analyze the literature to focus on a comprehensive treatment plan for those with DBT. It is currently suggested that with the use of dialectical behavioral therapy (DBT), a therapy that focuses on changing negative thinking patterns and pushes for more positive ones is helpful for treatment for those with BPD. Though this therapy is not a cure to BPD, it does help mitigate the risk; this essay will explore other options that can further the treatment process, such as cognitive analytical therapy (CAT), which focuses on delving into the past to find the root causes of an issue to create coping strategies and harm reduction, a type of therapy used to aid patients in lowering the use of substances without complete cessation. Results: The research provides enough evidence to link between the treatment of BPD with the utilization of CAT.

Keywords: borderline personality disorder, cognitive analytical therapy, dialectical behavioral therapy, harm reduction, suicidal ideation

Procedia PDF Downloads 174
2063 Virtual Reality as a Method in Transformative Learning: A Strategy to Reduce Implicit Bias

Authors: Cory A. Logston

Abstract:

It is imperative researchers continue to explore every transformative strategy to increase empathy and awareness of racial bias. Racism is a social and political concept that uses stereotypical ideology to highlight racial inequities. Everyone has biases they may not be aware of toward disparate out-groups. There is some form of racism in every profession; doctors, lawyers, and teachers are not immune. There have been numerous successful and unsuccessful strategies to motivate and transform an individual’s unconscious biased attitudes. One method designed to induce a transformative experience and identify implicit bias is virtual reality (VR). VR is a technology designed to transport the user to a three-dimensional environment. In a virtual reality simulation, the viewer is immersed in a realistic interactive video taking on the perspective of a Black man. The viewer as the character experiences discrimination in various life circumstances growing up as a child into adulthood. For instance, the prejudice felt in school, as an adolescent encountering the police and false accusations in the workplace. Current research suggests that an immersive VR simulation can enhance self-awareness and become a transformative learning experience. This study uses virtual reality immersion and transformative learning theory to create empathy and identify any unintentional racial bias. Participants, White teachers, will experience a VR immersion to create awareness and identify implicit biases regarding Black students. The desired outcome provides a springboard to reconceptualize their own implicit bias. Virtual reality is gaining traction in the research world and promises to be an effective tool in the transformative learning process.

Keywords: empathy, implicit bias, transformative learning, virtual reality

Procedia PDF Downloads 191
2062 Examining the Influences of Exchange Programmes on Youths' National Identity: A Hong Kong Case Study

Authors: Annie Y. N. Cheng

Abstract:

Since the handover of Hong Kong to China, 'National Identity' has become a vital focus promoted by the HKSAR government. According to the poll by the University of Hong Kong’s Public Opinion Programme (2010 – 2015), young people aged between 18 and 29 have the least and decreasing recognition, an average 5.5%, of their Chinese identity. Past research has shown that student participation in exchange programmes and study tours provides the possibility of new formulations of national identity. Since the Policy Address 2008, the HKSAR government has been actively expanding and exploring the feasibility of Mainland exchange programmes to enhance our youths’ understanding of Chineseness and to strengthen their national identity. Schools have been sponsored or subsidized with the costs of Mainland exchange activities through various grants and channels. Considering the significantly increasing number of Hong Kong youths who have participated in these Mainland exchange programmes and study tours, however, the effectiveness of these activities is understudied. At present, there is the lack of systematic research on the impacts of these activities and the ways in which they influence our students’ perceptions of national identity. Using case study approach, this study aims to examine students’ perceptions of their national identity; and evaluate whether the Mainland exchange programmes or study tours have influences on students’ perceptions of national identity. Results show that the influences on national identity varied which were dependent on the objectives and destinations of the programmes. The findings of this study can provide significant feedback for schools to organize meaningful Mainland exchange activities or study tours and inform policy makers how to formulate effective strategies for promoting such exchange activities.

Keywords: Hong Kong youth, mainland exchange programme, national identity, study tours

Procedia PDF Downloads 392
2061 Energy Budgeting, Carbon and Water Footprints Under Conventional and Conservation Tillage Practices of Rice-Wheat Double Cropping System

Authors: Ahmad Latif Virk, Naeem Ahmad, Muhammad Ishaq Asif Rehmani

Abstract:

Amid the present environmental crises, developing environment-resilient and cost-effective conservation agriculture strategies to feed the world's ever-growing population is pertinent. Therefore, a field study was conducted to test the hypothesis that residue retention under no-till (NTR) would enhance energy productivity (EP) and energy use efficiency (EUE) while offsetting the carbon footprints (CF), water footprints (WF) and greenhouse gases emissions (GHGs) in rice (Oryza sativa L.)-wheat (Triticum aestivum L.) double cropping system. Two tillage systems viz., conventional tillage (CT) and conservation tillage (no-till; NT), with or without residue retention, were combined into four treatments as CT0 (puddled rice, conventional wheat - residue); CTR (puddled rice, conventional wheat + residue); NT0 (direct rice seeding, zero-tilled wheat - residue); NTR (direct rice seeding, zero-tilled wheat + residue) were evaluated. Overall, results showed that the NT system had 34.2% lower energy consumption, 1.2 times more EP than CT system. Moreover, NTR had 19.8% higher EUE than CT0. The overall system grain yield ranged from 7.8 to 9.3 Mg ha−1 under NT0 and CTR, respectively. The NTR had 56.6% and 17.9% lesser CF and WF, respectively, than CT0. The net GHGs emissions (CO2-eq kg ha−1) under CT0 were the highest, while NTR had the lowest emissions. The NTR enhanced carbon sequestration in soil that can offset half of the system's CO2 emissions. The findings of this study might help develop a suitable strategy for resource/energy conservation and higher productivity while offsetting GHGs emissions in the Indo-Gangetic Plains.

Keywords: residue, yield, indirect emissions, energy use efficiency, carbon sequestration

Procedia PDF Downloads 81
2060 World Agricultural Commodities Prices Dynamics and Volatilities Impacts on Commodities Importation and Food Security in West African Economic and Monetary Union Countries

Authors: Baoubadi Atozou, Koffi Akakpo

Abstract:

Since the decade 2000, the use of foodstuffs such as corn, wheat, and soybeans in biofuel production has been growing sharply in the United States, Canada, and Europe. Thus, prices for these agricultural products are rising in the world market. These cereals are the most important source of calorific energy for West African Economic and Monetary Union (WAEMU) countries members’ population. These countries are highly dependent on imports of most of these products. Thereby, rising prices can have an important impact on import levels and consequently on food security in these countries. This study aims to analyze the interrelationship between the prices of these commodities and their volatilities, and their effects on imports of these agricultural products by each WAEMU ’country member. The Autoregressive Distributed Lag (ARDL) model, the GARCH Multivariate model, and the Granger Causality Test are used in this investigation. The results show that import levels are highly and significantly sensitive to price changes as well as their volatility. In the short term as well as in the long term, there is a significant relationship between the prices of these products. There is a positive relationship in general between price volatility. And these volatilities have negative effects on the level of imports. The market characteristics affect food security in these countries, especially access to food for vulnerable and low-income populations. The policies makers must adopt viable strategies to increase agricultural production and limit their dependence on imports.

Keywords: price volatility, import of agricultural products, food safety, WAEMU

Procedia PDF Downloads 186
2059 Predictive Pathogen Biology: Genome-Based Prediction of Pathogenic Potential and Countermeasures Targets

Authors: Debjit Ray

Abstract:

Horizontal gene transfer (HGT) and recombination leads to the emergence of bacterial antibiotic resistance and pathogenic traits. HGT events can be identified by comparing a large number of fully sequenced genomes across a species or genus, define the phylogenetic range of HGT, and find potential sources of new resistance genes. In-depth comparative phylogenomics can also identify subtle genome or plasmid structural changes or mutations associated with phenotypic changes. Comparative phylogenomics requires that accurately sequenced, complete and properly annotated genomes of the organism. Assembling closed genomes requires additional mate-pair reads or “long read” sequencing data to accompany short-read paired-end data. To bring down the cost and time required of producing assembled genomes and annotating genome features that inform drug resistance and pathogenicity, we are analyzing the performance for genome assembly of data from the Illumina NextSeq, which has faster throughput than the Illumina HiSeq (~1-2 days versus ~1 week), and shorter reads (150bp paired-end versus 300bp paired end) but higher capacity (150-400M reads per run versus ~5-15M) compared to the Illumina MiSeq. Bioinformatics improvements are also needed to make rapid, routine production of complete genomes a reality. Modern assemblers such as SPAdes 3.6.0 running on a standard Linux blade are capable in a few hours of converting mixes of reads from different library preps into high-quality assemblies with only a few gaps. Remaining breaks in scaffolds are generally due to repeats (e.g., rRNA genes) are addressed by our software for gap closure techniques, that avoid custom PCR or targeted sequencing. Our goal is to improve the understanding of emergence of pathogenesis using sequencing, comparative genomics, and machine learning analysis of ~1000 pathogen genomes. Machine learning algorithms will be used to digest the diverse features (change in virulence genes, recombination, horizontal gene transfer, patient diagnostics). Temporal data and evolutionary models can thus determine whether the origin of a particular isolate is likely to have been from the environment (could it have evolved from previous isolates). It can be useful for comparing differences in virulence along or across the tree. More intriguing, it can test whether there is a direction to virulence strength. This would open new avenues in the prediction of uncharacterized clinical bugs and multidrug resistance evolution and pathogen emergence.

Keywords: genomics, pathogens, genome assembly, superbugs

Procedia PDF Downloads 195
2058 Prevalence of the Double Burden of Malnutrition in Women of Childbearing Age in Morocco: Coexistence of Iron Deficiency Anemia and Overweight

Authors: Fall Abdourahmane, Lazrak Meryem, El Hsaini Houda, El Ammari Laila, Gamih Hasnae, Yahyane Abdelhakim, Benjouad Abdelaziz, Aguenaou Hassan, El Kari Khalid

Abstract:

Introduction: The double burden of malnutrition (DBM), characterized by the coexistence of undernutrition and overnutrition, is a significant health challenge, particularly in low- and middle-income countries. In Morocco, 61.3% of women of reproductive age (WRA) are overweight or obese, including 30.4% who were obese, while 34.4% were anaemic, and 49.7% have iron deficiency anaemia. Objective: This study aims to determine the prevalence of DBM at the individual level among Moroccan WRA, defined by the coexistence of iron deficiency anaemia and overweight/obesity. Methods: a cross-sectional national survey was conducted among a representative sample of 2090 Moroccan WRA. Data collected included socio-economic parameters, anthropometric measurements, and blood samples. Haemoglobin levels were measured photometrically using Hemocue, while ferritin and CRP were assessed through immunoturbudimetry. Results: The prevalence of overweight/obesity, iron deficiency, anaemia and iron deficiency anaemia among WRA in Morocco were 60.2%, 30.6%, 34.4% and 50.0% respectively. The coexistence of overweight/obesity with anaemia and iron deficiency was observed in 19.2% and 16.3% of women, respectively. Among overweight/obese women, 32.5% were anaemic, 28.4% were iron deficient, and 47.6% had iron deficiency anaemia. the prevalence of DBM was higher in urban areas compared to rural settings. Conclusion: The coexistence of undernutrition and overnutrition among WRA highlights the urgent need for integrated public health interventions addressing both anaemia and obesity simultaneously. Tailored strategies should consider the specific socio-economic and geographical contexts to effectively combat this dual burden.

Keywords: the double burden of malnutrition, iron deficiency anaemia, overweight, obesity

Procedia PDF Downloads 18
2057 Deriving Framework for Slum Rehabilitation through Environmental Perspective: Case of Mumbai

Authors: Ashwini Bhosale, Yogesh Patil

Abstract:

Urban areas are extremely complicated environmental settings, where health and well-being of an individual and population are governed by a large number of bio-physical, socio-economical, and inclusive aspects. Although poverty and slums are the prime issues under UN-HABITAT agenda of environmental sustainability, slums, the inevitable part of urban environment, have not accounted for inclusive city planning. Developing nations, where about 60 % of world slum population resides, are increasingly under pressure to uplift the urban poor, particularly slum dwellers. From a point of advantage, these new slum redevelopment projects have succeeded in providing legitimized and more permanent and stable shelter for the low income people, as well as individualized sanitation and water supply. However, they unfortunately follow the “one type fits all" approach and exhibit no response to the climatic design needs on Mumbai. The thesis focuses on the study of environmental perspectives in the context of Daylight, natural ventilation and social aspects in the design process of Slum-Rehabilitation schemes (SRS) – case of Mumbai. It attempts to investigate into Indian approaches about SRS and concludes upon strategies to be incorporated in SRS to improve the overall SRS environment. The main objectives of this work have been to identify and study the spatial configuration and possibilities of daylight and natural ventilation in Slum Rehabilitated buildings. The performance of the proposed method was evaluated by comparison with the daylight luminance simulated by lighting software, namely ECOTECT, and with measurements under real skies whereas for the ventilation study purpose, software named FLOW DESIGN was used.

Keywords: urban environment, slum-rehabilitation, daylight, natural-ventilation, architectural consequences

Procedia PDF Downloads 383
2056 Memory Consolidation: Application of Retrieval Strategies in the Classroom

Authors: Eric Tardif, Nicolas Meylan

Abstract:

Recent studies suggest that the consolidation of episodic memory is better achieved through repeated retrieval than with the use of concept mapping or repeated study. Although such laboratory results highly appeal to educationalists, it remains to be shown whether they can be directly used in a classroom setting. Forty-five college students (42 girls; mean age 16.1 y/o) were asked to remember pairs of biology-related words (e.g. mitochondria-energy) in two configurations. The first configuration consisted of a three-minute study of pairs of words followed by a final one-minute test in which the first word of a pair was shown and the subject asked to write down the second associated word. This procedure was repeated three times. The second configuration consisted of a one-minute study of a list of pairs of words, which was immediately followed by a one-minute test. This procedure was repeated 6 times. Subjects filled out a small questionnaire assessing their general mood, level of fatigue, stress and motivation to do the exercise. One week later, subjects were given a final test using the same words. A total of 8 lists of words were studied and tested during the semester. Results showed that subjects recalled more correct words when using the second configuration, both within the study period and one week later, confirming laboratory findings. However, the general performance (mean items recalled) as well as the motivation to do the exercise gradually decreased during the semester. Motivation was positively correlated with performance (r=0.77, p<0.05). The results suggest that laboratory findings may provide some applications in education but other variables inherent to the classroom setting must also be considered.

Keywords: long-term, episodic memory, consolidation, retrieval, school setting

Procedia PDF Downloads 337
2055 Analysis of Key Factors Influencing Muslim Women’s Buying Intentions of Clothes: A Study of UK’s Ethnic Minorities and Modest Fashion Industry

Authors: Nargis Ali

Abstract:

Since the modest fashion market is growing in the UK, there is still little understanding and more concerns found among researchers and marketers about Muslim consumers. Therefore, the present study is designed to explore critical factors influencing Muslim women’s intention to purchase clothing and to identify the differences in the purchase intention of ethnic minority groups in the UK. The conceptual framework is designed using the theory of planned behavior and social identity theory. In order to satisfy the research objectives, a structured online questionnaire was published on Facebook from 20 November to 21 March. As a result, 1087 usable questionnaires were received and used to assess the proposed model fit through structural equation modeling. Results revealed that social media does influence the purchase intention of Muslim women. Muslim women search for stylish clothes that provide comfort during summer while they prefer soft and subdued colors. Furthermore, religious knowledge and religious practice, and fashion uniqueness strongly influence their purchase intention, while hybrid identity is negatively related to the purchase intention of Muslim women. This research contributes to the literature linked to Muslim consumers at a time when the UK's large retailers were seeking to attract Muslim consumers through modestly designed outfits. Besides, it will be helpful to formulate or revise product and marketing strategies according to UK’s Muslim women’s tastes and needs.

Keywords: fashion uniqueness, hybrid identity, religiosity, social media, social identity theory, structural equation modeling, theory of planned behavior

Procedia PDF Downloads 219
2054 Application of Analytic Hierarchy Process Model to Weight and Prioritize Challenges and Barriers to Strategic Approach

Authors: Mohammad Mehdi Mohebi, Nima Kazempour, Mohammad Naeim Kazempour

Abstract:

Strategic thinking enables managers to find out what factors are effective in achieving the desired goals and how these factors create value for the customer. Strategic thinking can be interpreted as a form of mental and inner strength in the manager, who by utilizing it, while considering the conditions of the environment and unstable global environment changes, takes decisions, and plans actions, and designs the strategy of his organization in today's changing and unsustainable business environment. Strategic thinking is very important in today’s business world, because without this thinking, the organization's efforts to achieve developed strategies will not be effective. In this study, through a detailed study of the challenges and barriers to strategic thinking that is carried out by various scholars and experts theoretically and experimentally, 7 major factors were identified. Then, based on these main factors of challenges and related elements, a tool in the form of a questionnaire was developed in order to determine their importance and priority from the perspective of strategic management experts. Using statistical tests the reliability and validity of this instrument, including its structural validity, has been examined and approved using factor analysis. These factors are weighted and prioritized using AHP techniques and the opinions of scholars and experts. Prioritization of barriers to strategic thinking include: lack of participatory management, lack of a systematic approach, difficulty in aligning the organization members, lack of incentive organizational culture, behavioural and internal barriers of managers, lack of key managers and lack of access to timely and accurate information.

Keywords: strategic thinking, challenges and barriers to strategic thinking, EN bank, AHP method

Procedia PDF Downloads 540
2053 Disrupting Patriarchy: Transforming Gender Oppression through Dialogue between Women and Men at a South African University

Authors: S. van Schalkwyk

Abstract:

On international levels and across disciplines gender scholars have argued that patriarchal scripts of masculinity and femininity are harmful as they negatively impact constructions of selfhood and relations between women and men. Patriarchal ideologies serve as a scaffolding for dominance and subordination and fuel violence against women. Toxic masculinity—social discourses of men as violent, unemotional, and sexually dominant—are embedded in South African culture and are rooted in the high rates of gender violence occurring in the country. Finding strategies that can open up space for the interrogation of toxic masculinity is crucial in order to disrupt the destructive consequences of patriarchy in educational and social contexts. The University of the Free State (UFS) in South Africa in collaboration with the non-profit organization Gender Reconciliation International conducted a year-long series of workshops with male and female students. The aim of these workshops was to facilitate healing between men and women through collective dialogue processes. Drawing on a collective biography methodology outlined by feminist poststructuralists, this paper explores the impact of these workshops on gender relations. Findings show that the students experienced significant psychological connections with others during these dialogues, through which they began to interrogate their own gendered conditioning and harmful patriarchal assumptions and practices. This paper enhances insights into the possibilities for disrupting patriarchy in South African universities through feminist collective research efforts.

Keywords: collective biography methodology, South Africa, toxic masculinity, transforming gender oppression, violence against women

Procedia PDF Downloads 476
2052 Evaluation of Modified Asphalt Mixture with Hospital Spun-Bond Waste for Enhanced Crack Resistance

Authors: Ziba Talaeizadeh, Taghi Ebadi

Abstract:

Hospitals and medical centers generate a wide array of infectious waste on a daily basis, leading to pressing environmental concerns associated with proper disposal. Disposable plastic items and spun-bond clothing, commonly made from polypropylene, pose a significant risk of disease transmission, necessitating specialized waste management strategies. Incorporating these materials into bituminous asphalt production offers a potential solution, as it can modify asphalt mixtures and reduce susceptibility to cracking. This study aims to assess the crack resistance of asphalt mixtures modified with hospital spun-bond waste. Asphalt mixtures were prepared using the Marshall method, with spun-bond waste added in varying proportions (5% to 20%). The Semi-Circular Bending (SCB) test was conducted to evaluate asphalt fracture behavior under Mode I loading at controlled speeds of 5, 20, and 50 millimeters per minute and an average temperature of 25°C. Parameters such as fracture energy (FE) and Crack Resistance Index (CRI) were quantified. The results indicate that the addition of 10% to 15% spun-bond polypropylene polymer enhances the performance of the modified mixture, resulting in an 18% increase in fracture energy and an 11% reduction in cracking stiffness compared to the control sample. Further investigations involving factors like compaction level, bitumen type, and aggregate grading are recommended to address medical waste management and mitigate asphalt pavement cracking issues.

Keywords: asphalt cracking, hospital waste, semi-circular bending test, spun-bond

Procedia PDF Downloads 56
2051 Psycho-Social Problems Faced by Transgenders in Pakistani Society: A Qualitative Study

Authors: Amna bibi, Hina Rana

Abstract:

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 19
2050 Psycho-Social Problems Faced by Transgenders in Pakistani Society: A Qualitative Study”

Authors: Amna Bibi, Hina Rana

Abstract:

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 26
2049 Approach on Conceptual Design and Dimensional Synthesis of the Linear Delta Robot for Additive Manufacturing

Authors: Efrain Rodriguez, Cristhian Riano, Alberto Alvares

Abstract:

In recent years, robots manipulators with parallel architectures are used in additive manufacturing processes – 3D printing. These robots have advantages such as speed and lightness that make them suitable to help with the efficiency and productivity of these processes. Consequently, the interest for the development of parallel robots for additive manufacturing applications has increased. This article deals with the conceptual design and dimensional synthesis of the linear delta robot for additive manufacturing. Firstly, a methodology based on structured processes for the development of products through the phases of informational design, conceptual design and detailed design is adopted: a) In the informational design phase the Mudge diagram and the QFD matrix are used to aid a set of technical requirements, to define the form, functions and features of the robot. b) In the conceptual design phase, the functional modeling of the system through of an IDEF0 diagram is performed, and the solution principles for the requirements are formulated using a morphological matrix. This phase includes the description of the mechanical, electro-electronic and computational subsystems that constitute the general architecture of the robot. c) In the detailed design phase, a digital model of the robot is drawn on CAD software. A list of commercial and manufactured parts is detailed. Tolerances and adjustments are defined for some parts of the robot structure. The necessary manufacturing processes and tools are also listed, including: milling, turning and 3D printing. Secondly, a dimensional synthesis method applied on design of the linear delta robot is presented. One of the most important key factors in the design of a parallel robot is the useful workspace, which strongly depends on the joint space, the dimensions of the mechanism bodies and the possible interferences between these bodies. The objective function is based on the verification of the kinematic model for a prescribed cylindrical workspace, considering geometric constraints that possibly lead to singularities of the mechanism. The aim is to determine the minimum dimensional parameters of the mechanism bodies for the proposed workspace. A method based on genetic algorithms was used to solve this problem. The method uses a cloud of points with the cylindrical shape of the workspace and checks the kinematic model for each of the points within the cloud. The evolution of the population (point cloud) provides the optimal parameters for the design of the delta robot. The development process of the linear delta robot with optimal dimensions for additive manufacture is presented. The dimensional synthesis enabled to design the mechanism of the delta robot in function of the prescribed workspace. Finally, the implementation of the robotic platform developed based on a linear delta robot in an additive manufacturing application using the Fused Deposition Modeling (FDM) technique is presented.

Keywords: additive manufacturing, delta parallel robot, dimensional synthesis, genetic algorithms

Procedia PDF Downloads 187
2048 Isolation and Characterization of Bacteriophages Against Aeromonas Spp. Mediated Diseases in Indian Aquaculture

Authors: Mrunalini Sonne

Abstract:

Aquaculture uses a variety of broad spectrum antibiotics to manage and prevent a variety of diseases without understanding their mechanisms of action. This has led to water pollution in the modern world. The necessity for alternate control measures against bacterial illnesses in the aquaculture sector is highlighted by issues brought on by antibiotic-resistant bacteria and the dearth of effective control strategies. Bacteriophages (phages) have shown promise as therapeutic agents for the efficient management of bacterial infections in aquaculture. In the current study, a variety of investigations were conducted to determine if utilizing lytic phages to reduce Aeromonas spp. infection in fish aquaculture was appropriate. Motile Aeromonas septicaemia is a fish disease that has caused financial harm to the aquaculture sector. Currently, the production of aquaculture depends significantly on antibiotics, which adds to the worldwide problem of the rise of bacteria that are resistant to medicines and resistance genes. To decrease the usage of antibiotics in aquaculture systems, it is crucial to create efficient antibiotic substitutes. Bacteriophages are capable of acting as a natural antagonist, mostly because of their great specificity, capacity for self-replication, and ability to quickly eradicate dangerous bacteria. There is a need for research that goes beyond just isolating and characterising lytic bacteriophages to examine their morphology, stability, and efficacy in various environmental conditions. Bacteriophage (or phage) therapy is a promising technique to control dangerous microbes in farmed fish. More phage therapy research in aquaculture is required in order to effectively employ phage treatment to lessen infection in fish brought on by Aeromonas.

Keywords: aquaculture, bacteriophages, fish, freshwater

Procedia PDF Downloads 98
2047 Electron Bernstein Wave Heating in the Toroidally Magnetized System

Authors: Johan Buermans, Kristel Crombé, Niek Desmet, Laura Dittrich, Andrei Goriaev, Yurii Kovtun, Daniel López-Rodriguez, Sören Möller, Per Petersson, Maja Verstraeten

Abstract:

The International Thermonuclear Experimental Reactor (ITER) will rely on three sources of external heating to produce and sustain a plasma; Neutral Beam Injection (NBI), Ion Cyclotron Resonance Heating (ICRH), and Electron Cyclotron Resonance Heating (ECRH). ECRH is a way to heat the electrons in a plasma by resonant absorption of electromagnetic waves. The energy of the electrons is transferred indirectly to the ions by collisions. The electron cyclotron heating system can be directed to deposit heat in particular regions in the plasma (https://www.iter.org/mach/Heating). Electron Cyclotron Resonance Heating (ECRH) at the fundamental resonance in X-mode is limited by a low cut-off density. Electromagnetic waves cannot propagate in the region between this cut-off and the Upper Hybrid Resonance (UHR) and cannot reach the Electron Cyclotron Resonance (ECR) position. Higher harmonic heating is hence preferred in heating scenarios nowadays to overcome this problem. Additional power deposition mechanisms can occur above this threshold to increase the plasma density. This includes collisional losses in the evanescent region, resonant power coupling at the UHR, tunneling of the X-wave with resonant coupling at the ECR, and conversion to the Electron Bernstein Wave (EBW) with resonant coupling at the ECR. A more profound knowledge of these deposition mechanisms can help determine the optimal plasma production scenarios. Several ECRH experiments are performed on the TOroidally MAgnetized System (TOMAS) to identify the conditions for Electron Bernstein Wave (EBW) heating. Density and temperature profiles are measured with movable Triple Langmuir Probes in the horizontal and vertical directions. Measurements of the forwarded and reflected power allow evaluation of the coupling efficiency. Optical emission spectroscopy and camera images also contribute to plasma characterization. The influence of the injected power, magnetic field, gas pressure, and wave polarization on the different deposition mechanisms is studied, and the contribution of the Electron Bernstein Wave is evaluated. The TOMATOR 1D hydrogen-helium plasma simulator numerically describes the evolution of current less magnetized Radio Frequency plasmas in a tokamak based on Braginskii’s legal continuity and heat balance equations. This code was initially benchmarked with experimental data from TCV to determine the transport coefficients. The code is used to model the plasma parameters and the power deposition profiles. The modeling is compared with the data from the experiments.

Keywords: electron Bernstein wave, Langmuir probe, plasma characterization, TOMAS

Procedia PDF Downloads 93